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Everyone knows that muscle is much more attractive than fat. So when you lose weight, you want to build more muscle and not just diet to lose fat. But there are other health benefits to building muscle mass that should motivate you to hit the gym.

First of all, when you build muscle, you automatically reduce your percentage of body fat. And, you look better too. Muscle mass is approximately half as big as the mass of fat deposits.

That means that while five pounds of fat is approximately the size of three grapefruits, five pounds of muscle is more like three tangerines. Therefore, if you are exercising to lose weight, don’t be surprised if you actually gain weight. This is not a bad thing! It means you are building muscle mass, and you will look much slimmer than before.

Other health benefits of building muscle mass include burning calories more quickly. Muscles use energy, fat just stores it. So when you have more muscles, you will burn more energy and maintain a healthy body weight more easily.

You do not have to build a lot of muscle mass to reap the benefits. Studies show that building only five pounds of muscle mass will make you healthier and more able to fight off disease. It doesn’t take long to build muscle mass, either. Just thirty minutes three times a week is enough to reach your goals.

Lifting weights is the obvious way to build muscle mass, but swimming, running, or even walking will build muscle mass as well.

Objective: To assess the outcome of accelerated patient surveillance in patients at high risk for inherited breast or ovarian cancer. Methods: Using stringent inclusion criteria, 57 high-risk patients (7 positive for BRCA1/2 mutations, 39 mutation negative, and 11 unaffected) were recruited from a genetic testing protocol for inherited breast/ovarian cancer and were followed for 5 years (192.5 total patient years). Patients received twice annual physical examinations, imaging studies, measurement of CA125 and CA15-3, psychometric measurements, and unstructured interviews by a psychologist. Results: When mutation (+) and mutation (-) patients were compared, there were no significant differences in the development of disease metastasis, recurrence, or new cancers. No unaffected patients developed cancer. Management of osteoporosis, sexual function, and psychological distress were major concerns. Conclusions: Our data suggest that all patients with remarkable family history, regardless of their mutation status, may be at substantially increased risk for disease progression and development of new cancers, which is often not ovarian or recurrent breast cancer. Although prophylactic surgery is important in decreasing cancer recurrence in mutation carriers, increased surveillance with physical examinations and psychological support is also valuable and acceptable to such high-risk patients.

Over the average lifetime, one in eight women will be affected with breast cancer. Because of the common nature of this disease, many women may give a history of an affected family member. An estimated 5 to 10% of affected patients may have inherited a mutation in a gene that predisposes them to the development of breast cancer.1 Two such genes, BRCAl and BRCA2, have been well characterized and may account for 60 to 80% of cases of inherited breast cancer and 80 to 90% of cases of inherited breast/ovarian cancer.2 Mutations in BRCAl are associated with a 60 to 85% lifetime risk for the development of breast cancer and a 25 to 45% risk for the development of ovarian cancer;2·3 mutations in BRCA2 are also associated with a 75 to 85% risk for breast cancer development and an 11% risk for ovarian cancer.4 Approximately 3 to 14%of cases of male breast cancer, particularly if a family history of breast cancer is present, may be attributed to BRCA2 mutations.5 Nationwide, the estimated proportion of all cancer diagnoses by age 80 years, which are a result of germ-line BRCAl mutations, is 3.0% for breast cancer and 4.4% for ovarian cancer.6 Mutations in other genes, such as ataxia-telangiectasia, pTEN (breast and thyroid cancer), and H-ras, have also been associated with the development of breast cancer, although their characterization and dis ease development status is less clear. Undoubtedly, numerous other genes, yet undescribed, are also involved in inherited breast cancer.

Testing for BRCAl and BRCA2 mutations is available commercially. Although the long-term benefits of mutation identification are still under investigation, it is hoped that such identification will heighten vigilance for disease detection and will provide important information for families. The Familial Breast and Ovarian Cancer Research Project at Keesler Air Force Base (Mississippi) and Madigan Army Medical Center (Tacoma, WA; funded by Department of Defense/Health Affairs Breast Education and Awareness Project) was designed to develop a comprehensive approach for such patients, including the formation of educational materials, counseling approaches, and testing and follow-up guidelines. Testing methods, the outcomes of testing, and general guidelines for patient management have previously been reported.7,8 This article details the outcome of accelerated surveillance of patients who were identified through the testing protocol to be at high risk for new or recurrent disease based on their family history or the presence of a diagnosed BRCAl or 2 mutation.

Subjects and Methods

Patients were recruited from an Institutional Review Boardapproved protocol for inherited breast/ovarian cancer at Keesler Air Force Medical Center, Keesler Air Force Base and Madigan Army Medical Center for a separate Institutional Review Boardapproved Phase II surveillance study. The project was initiated in May 1997, with genetic testing offered through May 1999, when funding for testing was lost. The total study period was from May 1997 to May 2002. The patients were self-referred or were referred by their primary physician to the research project. They received extensive genetic counseling, pedigree analysis, records verification, and mutation risk prediction using the Couch model9, and they were offered genetic testing for BRCAl or 2 mutations if they met protocol guidelines and entered the project in the first 2 years (Table I). Patients unaffected with breast or ovarian cancer were not offered genetic testing unless there was a known BRCAl or 2 mutation in their family; however, because of the extreme anxiety of such patients, they were considered eligible for accelerated surveillance if they had at least one first-degree and one second-degree relative with breast or ovarian cancer.

Colorectal cancer is the third commonest malignancy in the United Kingdom, after lung and breast cancer, and kills about 20 000 people a year. It is equally prevalent in men and women, usually occurring in later life (at age 60-70 years). The incidence of the disease has generally increased over recent decades in both developed and developing countries. Despite this trend, mortality in both sexes has slowly declined. This decrease in mortality may reflect a trend towards earlier diagnosis–perhaps as a result of increased public awareness of the disease.

Most colorectal cancers result from malignant change in polyps (adenomas) that have developed in the lining of the bowel 10-15 years earlier. The best available evidence suggests that only 10% of 1 cm adenomas become malignant after 10 years. The incidence of adenomatous polyps in the colon increases with age, and although adenomatous polyps can be identified in about 20% of the population, most of these are small and unlikely to undergo malignant change. The vast majority (900/0) of adenomas can be removed at colonoscopy, obviating the need for surgery. Other types of polyps occurring in the colon–such as metaplastic (or hyperplastic) polyps–are usually small and are much less likely than adenomas to become malignant.

Colorectal cancer is therefore a common condition, with a known premalignant lesion (adenoma). As it takes a relatively long time for malignant transformation from adenoma to carcinoma, and outcomes are markedly improved by early detection of adenomas and early cancers, the potential exists to reduce disease mortality through screening asymptomatic individuals for adenomas and early cancers.

Which screening test for population screening?

Education about bowel cancer is poor. A survey in 1991 showed that only 30% of the British population were aware that cancer of the bowel could occur. Such ignorance only adds to the difficulties of early detection for this form of cancer.

For a screening test to be applicable to large populations it has to be inexpensive, reliable, and acceptable. Many different screening tests for detecting early colorectal cancer have been tried. The simplest and least expensive is a questionnaire about symptoms, but this has proved predictably insensitive and becomes reliable only when the tumour is relatively advanced. Digital rectal examination and rigid sigmoidoscopy both suffer from the limitation that they detect only rectal or rectosigmoid cancers and are unpleasant and invasive.

Flexible sigmoidoscopy

Flexible sigmoidoscopy can detect 80% of colorectal cancers as it examines the whole of the left colon and rectum. A strategy of providing single flexible sigmoidoscopy for adults aged 55-65 years–with the aim of detecting adenomas–may be cost effective. A multicentre trial of this strategy for population screening is currently under evaluation.

Although flexible sigmoidoscopy is more expensive than rigid sigmoidoscopy, it is generally more acceptable to patients (it is less uncomfortable) and has much higher yield than the rigid instrument. Many nurses are now trained to perform flexible sigmoidoscopy, making potential screening programmes using this technique more cost effective. In a population screening programme, uptake of the offer of the screening test is crucial. Uptake is likely to be around 45%, and, of these, 6% will subsequently need full colonoscopy. The effect that this will have on the incidence of and mortality from colorectal cancer is uncertain until the completion of the multicentre trial in 2003.

Colonoscopy

Colonoscopy is the gold standard technique for examination of the colon and rectum, but its expense, the need for full bowel preparation and sedation, and the small risk of perforation of the colon make it unacceptable for population screening. Colonoscopy is, however, the investigation of choice for screening high risk patients (those at risk of hereditary non-polyposis colon cancer or with longstanding ulcerative colitis).

Barium enema

Barium enema, like colonoscopy, examines the whole colon and rectum, and, although it is cheaper and has a lower complication rate than colonoscopy, it is invasive and requires full bowel preparation. Whereas colonoscopy may be therapeutic (polypectomy), barium enema does not allow removal or biopsy of lesions seen. There are no population screening studies using barium enema.

Faecal occult blood tests

Faecal occult blood tests are the most extensively studied screening tests for colorectal cancer. These tests detect haematin from partially digested blood in the stool. Their overall sensitivity for colorectal neoplasia is only 50-60%, though their specificity is high. In screening studies of faecal occult blood tests, individuals are invited to take two samples from each of three consecutive stools. Compliance is around 50-60%, but with population education this might be improved. Individuals with more than four out of six positive tests (about 2% of participants) need colonoscopy.

Every general practitioner in the United Kingdom will on average see one new case of colorectal cancer each year. For most primary care doctors the most important contributions they make to the care of patients with colorectal cancer relate to early diagnosis of the condition (including the point of referral) and to palliation of symptoms in those with established disease. Further roles in the future primary care service are screening for colorectal cancer (possibly using faecal occult blood testing) and a greater involvement in monitoring patients after curative procedures.

Early diagnosis of colorectal cancer is essential in view of the stage related prognosis. Three potential levels of delay occur in the diagnosis of the disease: delay by the patient in presenting to the general practitioner; delay in referral by the general practitioner to a specialist; and delay by the hospital in either establishing the diagnosis or starting treatment. Detrimental differences between England and Wales and the rest of western Europe in survival rates for colorectal cancer arise primarily in the first six months after diagnosis, suggesting that these differences relate to late presentations or delays in treatment.

Most patients developing colorectal cancer will eventually present with symptoms. Primary symptoms include rectal bleeding persistently without anal symptoms and change in bowel habit–most commonly, increased frequency or looser stools (or both)–persistently over six weeks. Secondary effects include severe iron deficiency anaemia and clear signs of intestinal obstruction. Clinical examination may show a definite right sided abdominal mass or definite rectal mass.

Unfortunately, many large bowel symptoms are common and non-specific and often present late. Recently published guidelines, however, make specific recommendations about which patients should be urgently referred–within two weeks–for further investigation in the NHS. The guidelines also indicate which symptoms are highly unlikely to be caused by colorectal cancer.

The risk of colorectal cancer in young people is low (99% occurs in people aged over 40 years and 85% in those aged over 60). In patients aged under 45, therefore, initial management will depend on whether they have a family history of colorectal cancer–namely, a first degree relative (brother, sister, parent, or child) with colorectal cancer presenting below the age of 55, or two or more affected second degree relatives. Patients aged under 45 presenting with alarm symptoms and a family history of the disease should also be urgently referred for further investigation.

In patients suspected of having colorectal cancer, referral should be indicated as urgent (with an appointment expected within two weeks); the referral letter should include any relevant family history and details about symptoms and risk factors. An increasing number of general practitioners will have direct access to investigations, often via a rapid access rectal bleeding clinic. The usual investigations needed will be flexible colonoscopy or barium enema studies.

In the absence of a family history of the disease, younger patients with a negative physical examination, including a digital rectal examination, can be initially treated symptomatically. If symptoms persist, however, patients should be considered for further investigation.

Patients with genetic predisposition

All patients registering with a practice for the first time should provide details of their medical history. Patients with a history of familial adenomatous polyposis should be referred for DNA testing after the age of 15. Familial adenomatous polyposis accounts for about 1% of cases of colorectal cancer, with the defect gene identified on chromosome 5. Patients with a positive result should enter a programme of surveillance with flexible sigmoidoscopy.

The second common genetic predisposition to colorectal cancer is hereditary non-polyposis colon cancer. This condition should be suspected in patients describing three or more cases of colorectal cancer (or andenocarcinoma of the uterus) within their family. Such patients should be referred for endoscopic screening at the age of 25. Genetic testing for this condition is currently not feasible.

In patients with a first degree relative with colorectal cancer aged under 45 or with two first degree relatives with the disease, the lifetime risk of the cancer rises to over 1 in 10. Such patients should be referred for lower endoscopy screening once they are 10 years younger than the age at which the disease was diagnosed in the youngest affected relative. An earlier article in this series gives more detail on the genetics of colorectal cancer.

Population screening in primary care

The United Kingdom currently has no national screening programme for colorectal cancer. Several studies in the United States and Europe have shown that screening with faecal occult blood testing will reduce the overall mortality of colorectal cancer by about 15%. Such testing is a fairly simple procedure: only two small samples from different sites of a stool need to be collected on each of three consecutive days. In the United States, the specimens are then normally hydrated, whereas research in the United Kingdom and Denmark advocates using dry samples. The latter technique results in a lower sensitivity, but higher specificity–desirable test performance characteristics for an asymptomatic population screening procedure.

Despite substantial improvements in surgical technique and postoperative care, colorectal cancer continues to kill 95 000 people in Europe alone each year.

Of the annual 150 000 newly diagnosed cases, about 80% have no macroscopic evidence of residual tumour after resection. More than half of patients, however, develop recurrence and die of their disease. This is a result of occult viable tumour cells that have metastasised before surgery and which are undetectable by current radiological techniques (the limit of detection of standard computed tomography is about 1 [cm.sup.3], equivalent to [10.sup.9] cells).

Adjuvant treatment (chemotherapy and radiotherapy) has developed as an auxiliary weapon to surgery and is aimed at eradicating these micrometastatic cancer cells before they become established and refractory to intervention. As the presence of the primary tumour can exert an inhibitory influence on micrometastases, theoretically the removal of the tumour might stimulate growth of any residual cells, increasing the proliferating fraction and rendering them more susceptible to the cytotoxic effects of the widely used cytotoxic agent, fluorouracil.

It is reasonable to predict therefore that the earlier chemotherapy is started after surgery, the greater the potential benefit, although this has not yet been formally addressed in adjuvant trials. Implicit in this belief is a necessity for a multidisciplinary effort between surgeon, oncologist, and the community care team to provide seamless, streamlined cancer care for the individual patient.

Fluorouracil has remained the cornerstone chemotherapy for colorectal cancer for over 40 years. It is a prodrug that is converted intracellularly to various metabolites that bind to the enzyme thymidylate synthase, inhibiting synthesis of thymidine, DNA, and RNA. Increasing understanding of the molecular pharmacology of fluorouracil has led to the development of strategies to increase its efficacy.

The first strategy to be tested was coadministration with the immunostimulatory, antihelminthic drug levamisole, but despite promising early results, recent trials have not convincingly shown significant improvements in outcome compared with fluorouracil alone. In addition, no persuasive mechanism for the assumed synergism between fluorouracil and levamisole has been found.

In contrast, addition of folinic acid increases and prolongs the inhibition of the target enzyme (thymidylate synthase) and seems to confer improved clinical outcome compared with fluorouracil alone in advanced disease and when used in adjuvant therapy.

The side effects of chemotherapy based on fluorouracil vary according to the regimen (most commonly given as bolus intravenously daily for 5 days every 4 weeks or bolus weekly). They include nausea, vomiting, an increased susceptibility to infection, oral mucositis, diarrhoea, desquamation of the palms and soles, and, rarely, cardiac and neurological toxic effects.

Established benefits of fluorouracil based adjuvant chemotherapy

Early adjuvant trials were retrospective and underpowered and failed to show any therapeutic benefit with respect to recurrence rate or survival. In 1990, however, the results of the intergroup trial were published. In this study 318 patients with stage B colorectal malignancy were randomised for surgical treatment alone or surgery followed by fluorouracil plus levamisole. In addition, 929 patients with stage C malignancy received surgery alone, surgery plus levamisole, or surgery plus fluorouracil and levamisole. For these patients there was a 33% reduction in the odds of death and a 41% decrease in recurrence among those treated with fluorouracil plus levamisole compared with surgery alone or surgery plus levamisole.

In contrast with levamisole, combining folinic acid with fluorouracil is pharmacologically rational, and documented benefit in advanced disease led to the logical extension of this combination into adjuvant therapy. Three large randomised adjuvant phase III trials produced confirmatory evidence of improved, disease-free survival at three years and improved overall survival in patients treated with fluorouracil plus folinic acid, with a 25-30% decrease in the odds of dying from colon cancer (or an absolute improvement in survival of 5-6% compared with controls).

Recently a meta-analysis of updated individual data from all unconfounded randomised studies of adjuvant chemotherapy (including the above three trials) has been undertaken (Colorectal Cancer Collaborative Group, unpublished). Overall, there was a 6-7% absolute improvement in survival with chemotherapy compared with surgery alone (SD 2.3, P = 0.01). The analysis advised that on current evidence the combination of fluorouracil plus folinic acid should be accepted as “standard” adjuvant chemotherapy for patients with Dukes’s type C colon cancer.

Controversies in adjuvant therapy

Despite convincing evidence that adjuvant chemotherapy improves disease-free survival and overall survival in Dukes’s type C colon cancer (an estimated six deaths prevented for 100 patients treated), several controversies surrounding the application of this form of treatment still exist.

The subject of colorectal cancer screening has filled many pages in the recent medical and lay press. Some authors have suggested combining use of stool cards for occult blood testing with sigmoidoscopy to increase the sensitivity of colon cancer detection. Lieberman and colleagues previously reported on the results of screening asymptomatic patients with colonoscopy to determine the rate at which examination of the distal colon detects advanced neoplasia. The authors now report on a separate analysis of the same study population, this time describing the results of patients who had stool card examinations before colonoscopy.

The authors examined 17,732 patient records to find 3,196 patients who were asymptomatic for any condition that might suggest bowel pathology (i.e., abdominal pain, rectal bleeding, change in stool habits) and had no serious co-morbid conditions or previous colon cancer screening. Stool card results before colonoscopy were available for 2,885 patients (92.4 percent). The cards were rehydrated before testing, which has been shown to increase the sensitivity of occult blood detection. The location and size of all lesions seen on colonoscopy were recorded, and lesions within the rectum and sigmoid colon served as a proxy for what would have been obtained by flexible sigmoidoscopy.

Advanced colonic neoplasia, defined as a tubular adenoma of 10 mm or more in diameter, any villous adenoma, adenoma with high-grade dysplasia, or invasive cancer was seen in approximately 11 percent of study participants. The combination of stool cards plus sigmoidoscopy would have identified 76 percent of all cases of advanced neoplasia. In the remaining 24 percent of cases, no lesions were within reach of the sigmoidoscope nor was there a positive stool card result (either of which factors would typically prompt a full colonoscopic examination). Although performing stool card testing before endoscopic examination would have reduced the total number of endoscopies needed to find all of the neoplasia cases (those with a positive stool card test would skip sigmoidoscopy and proceed to colonoscopy), the authors stated that it did not add significantly to the number of cases that would have been detected by sigmoidoscopy alone.

The authors conclude that performing stool card testing before sigmoidoscopy does not significantly increase the detection of colon cancer, and about one fourth of advanced colonic neoplasia cases would not be detected by this combined regimen.

In a surprising finding that contradicts conventional dietary wisdom, Harvard University researchers have discovered that a high-fiber diet does not appear to reduce the risk of colon cancer. However, the researchers and other cancer specialists stress high in fiber — which vegetables and whole grains — has other health benefits that still make it worthwhile to consume.

In the study, published in the latest New England Journal of Medicine, researchers tracked the colon and rectal health of more than 88,000 women who participated in the Harvard-based Nurses Health Study from 1980 to 1996. Of the women studied, 787 developed colon or rectal cancer. The risk was the same, regardless of how much fiber they ate.

The researchers said they were astounded by the findings, which contradict the conventional thinking about the link between fiber and colon cancer. However, previous similar studies in men also found that fiber does not lower the risk of colon cancer, and the researchers said they believe their new findings would also apply to men.

The recommended amount of fiber for a healthy diet is about 30 grams per day, about five to eight servings of fruits and vegetables. One researcher said he doubts his organization will change its nutritional guidelines because people who eat more fiber generally suffer fewer cases of other types of cancer. He also stressed that there may be other properties of vegetables, including the vitamin folate, that could lower the risk of cancer and that people who eat more fruits, vegetables and whole grains also tend to be less obese and suffer fewer health problems.

The researchers were quick to say that fiber is not necessarily a bad thing. “It is still helpful, but not for colon cancer,” they said. In addition a high-fiber diet has been shown to prevent other types of cancer, including that of the mouth, pharynx, larynx, esophagus and stomach. But none of these are as common as colorectal cancer, which is the second leading cancer among Americans with 57,000 deaths in 1998 (lung cancer is the number one killing cancer).

The researchers noted that the study had its limitations. For example, many scientists believe that men and women respond differently to dietary fat and fiber, and the study group involved only women. Still, the new study adds to growing research that suggests when it comes to colorectal cancer the benefits of fiber have yet to be proven.

In 1997, approximately 131,000 people in the United States were diagnosed with colorectal cancer and 55,000 died of the disease (Parker, Tong, Bolden, & Wingo as cited in Read & Kodner, 1999a). It is projected that 1 in 17 people in the United States will develop colorectal cancer during their lifetime. Colorectal cancer screening and appropriate treatment can reduce the morbidity and mortality from this devastating disease (Read & Kodner, 1999a).

Early detection and treatment of colorectal cancer, the second leading cause of cancer-related deaths, reduces mortality from the disease (Read & Kodner, 1999a). Nurses, particularly those in advanced practice, play a vital role in educating patients about risk factors and colorectal cancer screening. The risk factors for developing colorectal cancer and the screening recommendations are listed in Table 1.

Table 1. Colorectal Cancer Screening Recommendations

Level of Risk                     Screening Recommendation

Average level of risk.            Begin screening at age 50:

1. Fecal occult blood test
yearly, or

2. Flexible sigmoidoscopy every
5 years, or

3. #1 & #2 every 5 years, or

4. Double-contrast barium enema
(BaE) every 5-10 yrs, or

5. Colonoscopy every 10 years

Individuals with a family         Screen 10 years before diagnosis
history of colorectal cancer or   in the youngest family member or
adenomatous polyps.               age 40 whichever is first:
Colonoscopy every 10 years or
double contrast barium enema
every 5 years.

Individuals with a family         Screen at age 21: Colonoscopy
history of hereditary             every 1-3 years, genetic
nonpolyposis colorectal cancer.   counseling.

Individuals with a family         Screening at puberty: Flexible
history of familial adenomatous   sigmoidoscopy or colonoscopy
polyposis.                        every 1-2 years, genetic
counseling.

Individuals with ulcerative       Screen 7 to 8 years following
colitis.                          diagnosis of pancolitis or 12-15
years following diagnosis of
left-sided colitis: Colonoscopy
with biopsy every 1-2 years.

When the disease occurs, appropriate nursing care may reduce the emotional and physical suffering experienced by these patients. The purpose of this article is to describe the surgical procedure and discuss the educational needs, solutions to common problems, and the vital role of nursing in the care of patients having proctectomy and coloanal reservoir for treatment of rectal cancer.

Surgical Treatment

First described in 1908, abdominal perineal resection (APR) with a permanent colostomy was long the surgical technique of choice for treating rectal cancer. Unfortunately, it was associated with high morbidity rates (21% to 76%) and common problems included bleeding, impotence, and chronic urinary retention (Arnell & Stamos, 1996). More recently, several factors have led to the development of surgical procedures that restore intestinal continuity and eliminate the need for a permanent colostomy. These factors include a greater understanding of how rectal cancers spread, more effective use of chemotherapy and radiation therapy, and advancements in surgical instruments and techniques (Arnell & Stamos, 1996; Read & Kodner, 1999b).

A restorative procedure currently used is construction of a neorectum using descending colon referred to as a colonic pouch. Studies have shown that the colonic pouch-anal anastomosis provides better functional outcomes than a straight coloanal anastomosis (Dehni et al., 1998; Joo et al., 1998). Benefits of a colonic pouch compared to coloanal anastomosis include fewer bowel movements, less need for constipating agents, and fewer needs for dietary restrictions (Dehni et al., 1998).

In this procedure, the diseased rectum and appropriate tissues are removed and the colonic pouch is constructed in the shape of a “J” using 6 to 10 centimeters of colon. This neorectum is then attached to the anal stump with a colonic pouch-anal anastomosis. A temporary loop ileostomy is constructed to divert intestinal flow to minimize complications of anastomotic disruption and fecal incontinence from chemotherapy-induced diarrhea (Read & Kodner, 1996b).

Approximately 3 months after the first procedure, the patient will require a second surgery to take down the ileostomy and restore intestinal continuity. This surgery is performed only after completion of chemotherapy and evaluation of the pouch. The integrity of the colonic “J” pouch is evaluated endoscopically and radiographically (Read & Kodner, 1996b).

Population based studies show that for rectal cancer the incidence of local recurrence after apparently curative resection is about 20%. Local recurrence after surgery for colon cancer is less common. The liver is the commonest site of distant spread, followed by the lungs; brain and bone metastases are relatively rare. Most recurrences are within 24 months of surgery.

Traditionally surgeons have reviewed their patients at regular intervals after apparently curative resection. Recent surveys, however, have highlighted the lack of consensus among surgeons about the optimal modality and intensity of follow up; surveillance strategies range from a single postoperative visit to lifelong surveillance. Enthusiasts believe that intensive follow up and early intervention will lead to a reduction in the number of deaths from colorectal cancer; others point to the fact that the value of follow up is unproved. With so many tests available and no consensus on their value, it is not surprising that individual clinicians have tended to devise their own protocols.

A meta-analysis in the mid-1990s did little to clarity the situation. The researchers evaluated the results of seven non-randomised studies (covering over 3000 subjects in total) that compared intensive follow up with minimal or no follow up. Clearly several potential biases could and did exist. In the intensive group, investigations included clinical examination, faecal occult blood testing, liver function tests, measurement of the carcinoembyronic antigen, sigmoidoscopy, and either colonoscopy or barium enema examination. Liver ultrasonography was performed in only three studies and even then infrequently. In the intensive group more asymptomatic recurrences were detected, more patients underwent “second look” laparotomy, and more patients had a second potentially curative resection; more metachronous turnouts were also detected and resected. However, although there were fewer deaths in the group receiving intensive follow up, this difference did not reach significance.

Results of randomised clinical trials

Since the meta-analysis, four randomised trials of intensive follow up have been reported. Ohlsson and his colleagues randomised 107 patients to no follow up or to intensive follow up, similar to that described above. No liver imaging was performed routinely. No differences were found in recurrence rates or in overall or cancer specific mortality.

Makela and his associates compared conventional with intensive follow up in 106 patients. In the intensive group flexible sigmoidoscopy was performed every three months, ultrasonography every six months, and colonoscopy and abdominal computed tomography at yearly intervals. Recurrences were detected at an earlier stage (median 10 months v 15 months) in the intensive group. Despite this, no difference in survival was found between the two groups.

Kjeldsen and his colleagues randomised almost 600 patients to either six monthly follow up or to follow up visits at five and 10 years only. Investigations included chest x ray and colonoscopy; no routine liver imaging was performed. Recurrence rates were similar (26%) in both groups, but the recurrences in the intensive group were detected on average nine months earlier, often at an asymptomatic stage. More patients with local recurrence underwent repeat surgery with curative intent. No difference existed, however, in overall survival (68% v 70%) or cancer related survival.

More recently, Schoemaker and his colleagues evaluated the addition of annual chest radiography, colonoscopy, and computed tomography of the liver to a standard follow up based on clinical examination, faecal occult blood testing, liver function tests, and measurement of the carcinoembyronic antigen, with further investigations as clinically indicated. At five years, fewer patients in the intensive group had died, but the result was not significant. At the cost of 505 additional investigations, annual colonoscopy failed to detect any asymptomatic local recurrences; only one asymptomatic metachronous colon tumour was detected. Six hundred and eight additional liver computed tomograms detected only one asymptomatic patient with liver metastases who might have benefited from liver resection.

Carcinoembryonic antigen

Carcinoembryonic antigen concentrations have also been used to predict recurrence. About three quarters of patients with recurrent colorectal cancer have a raised carcinoembryonic antigen concentration before developing symptoms.

An alternative approach therefore would be to monitor this concentration regularly during follow up and, in those patients showing a rising concentration, undertake second look laparotomy. However, although early non-randomised studies suggested that surgery that was prompted by this method resulted in more potentially curative repeat operations for recurrence, more recent studies have failed to show a survival advantage.

Although colon cancer is the second leading cause of cancer mortality, only one half of adults at average risk have been screened. Virtual colonoscopy, which uses computed tomographic (CT) scanning to screen the whole colon for cancer-causing polyps, has been offered as a less invasive alternative to endoscopic examinations. However, earlier studies of patients at average risk revealed sensitivities as low as 48 percent for detection of polyps 1 cm or larger. Pickhardt and colleagues report on a large trial comparing same-day virtual and endoscopic colonoscopy for colon cancer screening in an average-risk patient cohort.

A total of 1,253 patients were enrolled, of whom 1,233 underwent both virtual and endoscopic colonoscopies. Six patients were excluded because of inadequate bowel preparation, six others did not have successful CT scans of the entire colon, and eight had incomplete endoscopic colon examinations. Virtual colonoscopy involved insertion of a rectal catheter and air insufflation of the colon, followed by CT scanning of the abdomen. This procedure took an average of 14.1 minutes to complete.

Two aspects of the CT protocol in this trial differed from previous studies. First, patients were given 500 mL of a barium solution to “tag” any remaining solid stool and 120 mL of an opacifying solution to tag any remaining intraluminal fluid. With the residual stool and fluid tagged, the scanning software was able to remove them from the CT images of the bowel. Second, this trial used three-dimensional CT image reconstructions as the primary screening modality, whereas previous studies had relied for the most part on standard two-dimensional CT images for polyp detection.

Experienced colonoscopists performed endoscopic colonoscopy after CT scanning was completed. Each colonic segment was first examined without knowledge of the virtual colonoscopy results and then re-examined if any polyp identified on CT scanning was missed by the initial endoscopic examination.

After virtual and endoscopic colonoscopies were completed, adenomatous polyps 6 mm or larger were detected in 13.6 percent of patients, and polyps 10 mm or larger were found in 3.9 percent. Virtual colonoscopy had a sensitivity of 88.7 percent for polyps 6 mm or larger and 93.8 percent for polyps 10 mm or larger compared with sensitivity rates of 92.3 and 87.5 percent, respectively, for endoscopic examination.

Compared with the reference standard of endoscopic colonoscopy and histopathologic examination of all resected polyps, the specificity of virtual colonoscopy was 79.6 percent for polyps 6 mm or larger and 96.0 percent for polyps 10 mm or larger. Virtual colonoscopy detected 55 polyps that were 5 mm or larger and were not seen on the initial endoscopic examination out of a total of 1,310 detected polyps (4.2 percent). Two malignant polyps were found overall. Both were seen on virtual colonoscopy, and one was missed on the initial endoscopic examination.

Virtual colonoscopy without sedation was rated by 54.3 percent of patients as the more uncomfortable examination, while the sedated endoscopic examination was rated as more uncomfortable by 38.1 percent; 7.6 percent of patients were undecided.

The authors conclude that the sensitivity and specificity of three-dimensional virtual colonoscopy for polyp detection are comparable to that of endoscopic colonoscopy.

Pickhardt PJ, et al. Computed tomographic virtual colonoscopy to screen for colorectal neoplasia in asymptomatic adults. N Engl J Med December 4, 2003;349: 2191-200.

EDITOR’S NOTE: This is the first large trial of virtual colonoscopy in an average-risk population demonstrating a diagnostic accuracy equivalent to that of endoscopic colonoscopy and providing an additional safety margin by detecting some polyps that were missed on endoscopic examination. If this accuracy can be confirmed in similar studies and cost-effectiveness can be demonstrated, the door may be opened for more widespread use of virtual colonoscopy. Of course, polyps cannot be removed during CT scanning. Using a size cutoff for polyp removal of 10 mm or larger, the authors of this trial calculated that one in 13 patients would have required an endoscopic examination subsequent to the virtual colonoscopy. Even with a conservative polyp size cutoff of 6 mm or larger, more than two thirds of patients would have avoided the need for endoscopic colonoscopy. If screening centers could duplicate the efficiency of the protocol used by these authors, so that all patients with polyps detected on virtual colonoscopy could have them removed endoscopically on the same day, taking advantage of the same bowel preparation, virtual colonoscopy might have an even greater appeal as an initial step in colon cancer screening.–B.Z.