Prospective randomized study of sulindac versus calcium and calciferol for upper gastrointestinal polyps in familial adenomatous polyposis

Chemoprevention in hereditary digestive neoplasia: A comprehensive review

Hereditary syndromes, such as familial adenomatous polyposis (FAP), MUTYH polyposis or Lynch syndrome, are particularly predisposing to the development of colorectal cancer. These situations have necessitated the development of adapted prevention strategies based largely on reinforced endoscopic surveillance and the search for complementary prevention strategies. This is the case for chemoprevention, which is the long-term administration of chemical agents limiting carcinogenesis, used as primary or secondary prophylaxis. The aim of this review is to present the available literature and the latest advances in chemoprevention in patients with FAP or MUTYH and other polyposis as well as in patients with Lynch syndrome. The main conclusions of the few available guidelines in these situations are also discussed.

Biology of Precancers and Opportunities for Cancer Interception: Lesson from Colorectal Cancer Susceptibility Syndromes

Hereditary gastrointestinal cancer is associated with molecular and neoplastic precursors which have revealed much about sporadic carcinogenesis. Therefore, an appreciation of constitutional and somatic events linked to these syndromes have provided a useful model for the development of risk models and preventative strategies. In this review, we focus of two of the best characterized syndromes, Lynch syndrome (LS) and familial adenomatous polyposis (FAP). Our understanding of the neoplasia-immune interaction in LS has contributed to the development of immune mediated therapies including cancer preventing vaccines and immunotherapy for cancer precursors. Chemoprevention in LS with aspirin and nonsteroidal anti-inflammatory drugs has also translated into clinical cancer, however the efficacy of such agents in FAP remains elusive when cancer is applied as an endpoint in trials rather than the use of 'indirect' endpoints such as polyp burden, and requires further elucidation of biological mechanisms in FAP. Finally, we review controversies in gastrointestinal surveillance for LS and FAP, including limitations and opportunities of upper and lower gastrointestinal endoscopy in the prevention and early detection of cancer.

Endoscopic management of non-ampullary duodenal adenomas

Duodenal polyps are found in 0.1 % to 0.8 % of all upper endoscopies. Duodenal adenomas account for 10 % to 20 % of these lesions. They can be sporadic or occur in the setting of a hereditary predisposition syndrome, mainly familial adenomatous polyposis. Endoscopy is the cornerstone of management of duodenal adenomas, allowing for diagnosis and treatment, primarily by endoscopic mucosal resection. The endoscopic treatment of duodenal adenomas has a high morbidity, reaching 15 % in a prospective study, consisting of bleeding and perforations, and should therefore be performed in expert centers. The local recurrence rate ranges from 9 % to 37 %, and is maximal for piecemeal resections of lesions > 20 mm. Surgical resection of the duodenum is flawed with major morbidity and considered a rescue procedure in cases of endoscopic treatment failures or severe endoscopic complications such as duodenal perforations. In this paper, we review the existing evidence on endoscopic diagnosis and treatment of non-ampullary duodenal adenomas.

The Effect of Metformin in Treatment of Adenomas in Patients with Familial Adenomatous Polyposis

Familial adenomatous polyposis (FAP) is a hereditary disease characterized by the development of numerous colorectal adenomas in young adults. Metformin, an oral diabetic drug, has been shown to have antineoplastic effects and a favorable safety profile. We performed a randomized, double-blind, controlled trial to evaluate the efficacy of metformin on the regression of colorectal and duodenal adenoma in patients with FAP. Thirty-four FAP patients were randomly assigned in a 1:2:2 ratio to receive placebo, 500 mg metformin, or 1,500 mg metformin per day orally for 7 months. The number and size of polyps and the global polyp burden were evaluated before and after the intervention. This study was terminated early based on the results of the interim analysis. No significant differences were determined in the percentage change of colorectal and duodenal polyp number over the course of treatment among the three treatment arms (P = 0.627 and P = 1.000, respectively). We found no significant differences in the percentage change of colorectal or duodenal polyp size among the three groups (P = 0.214 and P = 0.803, respectively). The overall polyp burdens of the colorectum and duodenum were not significantly changed by metformin treatment at either dosage. Colon polyps removed from the metformin-treated patients showed significantly lower mTOR signal (p-S6) expression than those from patients in the placebo arm. In conclusion, 7 months of treatment with 500 mg or 1,500 mg metformin did not reduce the mean number or size of polyps in the colorectum or duodenum in FAP patients (ClinicalTrials.gov ID: NCT01725490). PREVENTION RELEVANCE: A 7-month metformin treatment (500 mg or 1,500 mg) did not reduce the number or size of polyps in the colorectum or duodenum of FAP patients as compared to placebo. These results do not support the use of metformin to promote regression of intestinal adenomas in FAP patients.

Drug repurposing in oncology: Compounds, pathways, phenotypes and computational approaches for colorectal cancer

The strategy of using existing drugs originally developed for one disease to treat other indications has found success across medical fields. Such drug repurposing promises faster access of drugs to patients while reducing costs in the long and difficult process of drug development. However, the number of existing drugs and diseases, together with the heterogeneity of patients and diseases, notably including cancers, can make repurposing time consuming and inefficient. The key question we address is how to efficiently repurpose an existing drug to treat a given indication. As drug efficacy remains the main bottleneck for overall success, we discuss the need for machine-learning computational methods in combination with specific phenotypic studies along with mechanistic studies, chemical genetics and omics assays to successfully predict disease-drug pairs. Such a pipeline could be particularly important to cancer patients who face heterogeneous, recurrent and metastatic disease and need fast and personalized treatments. Here we focus on drug repurposing for colorectal cancer and describe selected therapeutics already repositioned for its prevention and/or treatment as well as potential candidates. We consider this review as a selective compilation of approaches and methodologies, and argue how, taken together, they could bring drug repurposing to the next level.

Spigelman stage IV duodenal polyposis does not precede most duodenal cancer cases in patients with familial adenomatous polyposis

BACKGROUND AND AIMS

The greatest known risk factor for duodenal cancer in familial adenomatous polyposis (FAP) is Spigelman stage (SS) IV duodenal polyposis. Endoscopic surveillance is recommended in FAP patients with SS 0 to IV, and prophylactic duodenectomy should be considered in SS IV. Cancer occurs in patients without SS IV polyposis. We assessed the relationship of SS and other factors with duodenal cancer in FAP.

METHODS

We performed a case-control study on 18 FAP patients with duodenal cancer and 85 randomly selected FAP control subjects with similar age characteristics. Demographic, clinical, and endoscopic features were compared using univariate and logistic regression analyses to assess factors associated with duodenal cancer.

RESULTS

Fifty-three percent of cases had no SS IV history. SS components positively associated with cancer included duodenal polyp size (77% vs 47%, P = .015), and high-grade dysplasia (HGD; 29% vs 6%, P = .003) but not polyp number or histology. In the papilla, the frequency of tubulovillous or villous histology (80% vs 22%, P < .001) and HGD (30% vs 4%, P = .010) was greater in cases than control subjects.

CONCLUSIONS

SS IV polyposis was absent in half of FAP patients with duodenal cancer. Only 2 of 4 SS components (large duodenal polyp size and HGD) were positively associated with duodenal cancer. Advanced pathology of the papilla appears to be an important feature. Revision of SS to emphasize these findings should be considered to better estimate cancer risk.

Chemoprevention of familial adenomatous polyposis

Familial adenomatous polyposis (FAP) has always been first and foremost a surgical disease, whose treatment with colectomy has long been known to reduce risk of premature cancer death. The notion of reducing polyp burden and potentially delaying surgical intervention has spawned a host of "chemoprevention" trials. In this paper I selectively review the findings from these studies, highlighting trial design issues and in particular some of the limitations of historical and existing trial endpoint measures. Nonsteroidal anti-inflammatory agents have been the most commonly employed chemopreventive agents. Sulindac, largely by historical accident, has been the most extensively studied, and is widely considered the standard of care when a clinical decision to intervene medically is made. Newer trials are evaluating combinations of agents in order to take advantage of differing mechanisms of action, in the hope of achieving synergy, as no single agent predictably or completely suppresses adenoma growth. Some of these studies and other single-agent interventions are discussed, though an exploration of the various mechanisms of action is beyond the scope of this paper. It is essential that future trials focus on the issue of "clinical benefit", not simply because the US Food and Drug Administration has insisted on it, but because only real evidence-based advances can improve the standard of medical care for FAP patients. Hence my focus on issues of trial design and clinically relevant endpoints.

The effect of ursodesoxycholic acid on duodenal adenomas in familial adenomatous polyposis: a prospective randomized placebo-control trial

AIM

Duodenal adenomas occur in about 90% of patients with familial adenomatous polyposis (FAP) and are the second cause of death of patients who have had a prophylactic proctocolectomy. Studies suggest that biliary acids have a role in the development of duodenal adenomas. The aim of this study was to evaluate the impact of ursodesoxycholic acid (UDCA) on duodenal adenoma formation in patients with FAP.

METHOD

A randomized, double-blinded, placebo-controlled study was carried out of 71 patients (20-65 years) who already had a restorative proctocolectomy. Subjects received either 10 mg/kg of UDCA orally per day or a placebo tablet for 24 months. The Spigelman severity score was determined after duodenal axial and lateral view endoscopy at 12 and 24 months.

RESULTS

At 2 years 55 patients had completed the entire period of treatment. At the end of the follow-up period, nine (25%) patients in the UDCA group and seven (20%) in the placebo group had a decrease in the Spigelman score (P = 0.6142). Patients receiving UDCA had no side-effects (0%) compared with four (14%) in the placebo group (P = 0.0392).

CONCLUSION

UDCA had no effect on the development of duodenal adenomas in FAP patients (NCT: 00134758).

Chemoprevention in familial adenomatous polyposis

Familial adenomatous polyposis (FAP) predictably leads to adenomas and eventual adenocarcinomas in the lower gastrointestinal tract and less frequently, the upper gastrointestinal tract. Chemopreventive strategies have been studied in FAP patients to delay the development of adenomas in the upper and lower gastrointestinal tract, as well as to prevent recurrence of adenomas in the retained rectum of patients after prophylactic surgery with colectomy and ileorectal anastamosis (IRA). The nonsteroidal anti-inflammatory drug (NSAID) sulindac and selective cyclooxygenase-2 (COX-2) inhibitor celecoxib reduce polyposis of the retained rectum after colectomy with IRA. Reports of cardiovascular risks of some NSAIDs and selective COX-2 inhibitors have led to promising studies of lower doses in combination with ursodeoxycholic acid, statin, and difluoromethylornithine. Curcumin and eicosapentaenoic acid show efficacy in small clinical trials of FAP chemoprevention. This article will review the concept of chemoprevention and the current clinical literature in FAP chemoprevention.

Pancreaticoduodenectomy for advanced duodenal and ampullary adenomatosis in familial adenomatous polyposis

BACKGROUND

Patients with familial adenomatous polyposis (FAP) develop duodenal and ampullary polyps that may progress to malignancy via the adenoma-carcinoma sequence.

OBJECTIVE

The aim of this study was to review a large series of FAP patients undergoing pancreaticoduodenectomy for advanced duodenal and ampullary polyposis.

METHODS

A retrospective case notes review of all FAP patients undergoing pancreaticoduodenectomy for advanced duodenal and ampullary adenomatosis was performed.

RESULTS

Between October 1993 and January 2010, 38 FAP patients underwent pancreaticoduodenectomy for advanced duodenal and ampullary polyps. Complications occurred in 29 patients and perioperative mortality in two. Postoperative histology revealed five patients to have preoperatively undetected cancer (R = 0.518, P < 0.001).

CONCLUSIONS

Pancreaticoduodenectomy in FAP is associated with significant morbidity, but low mortality. All patients under consideration for operative intervention require careful preoperative counselling and optimization.

Functional outcome after restorative proctocolectomy in pigs: comparing a novel transverse ileal pouch to the J-pouch and straight ileoanal anastomosis

BACKGROUND

Restorative proctocolectomy followed by an ileoanal J-pouch procedure is the therapy of choice for patients with familial adenomatous polyposis and ulcerative colitis. After low anterior rectal resection, the authors have reported on a novel, less complex pouch configuration, a transverse coloplasty pouch. The aim of the present work was to apply this new design to the ileal pouch construction, to evaluate feasibility, and to measure functional results in comparison with the J-pouch and the straight ileoanal anastomosis using the pig as an animal model.

METHODS

Twenty-three pigs underwent restorative proctocolectomy followed by reconstruction with straight ileoanal anastomosis (IAA; n = 5), J-pouch (n = 7), and a transverse ileal pouch (TIP; n = 11). Pigs were followed for 6 days postoperatively. Peristaltic function was assessed by manometry proximal to the pouch, in the reservoir, and at the level of the ileoanal anastomosis. Functional outcome was monitored by semiquantitative assessment of the general condition of the animals, postoperative feeding habits, and stool frequency and consistency. A Fourier analysis was performed in order to compare peristalsis in the ileal reservoirs. The reservoir volume was measured in situ by triple contrast computed tomography scan with 3D reconstruction.

RESULTS

Seventeen animals survived for 1 week. There was no difference in the general condition or the feeding habits of the groups. A significant number of pigs with the TIP pouch (7/10) had semisolid or formed stools as opposed to liquid stools after J-pouch (6/6) and IAA (4/5; p = 0.01). TIP animals had a lower stool frequency (3.2 +/- 1.14 per day) on day 6 after the operation than pigs with J-pouch, 5.33 +/- 1,03, and IAA, 4.6 +/- 1.82 (p = 0.0036). The in situ volume of the pouches did not differ significantly. The Fourier analysis demonstrated a disruption of peristalsis by the J-pouch and the TIP reconstruction but not after IAA.

CONCLUSION

The function of ileoanal reservoirs after proctocolectomy may result from the disruption of properistaltic waves after pouch formation. The mechanism of peristalsis disruption is independent of the in situ volume of the pouch.

[Familial adenomatous polyposis]

Familial adenomatous polyposis is a rare genetic disease characterized by the development of more than a hundred adenomatous polyps in the colorectal area, as well as by extracolonic manifestations. Without treatment, this inherited disease, usually transmitted by autosomal dominant inheritance, predisposes to colorectal cancer. Treatment must be preceded by counseling about the nature of the syndrome and by recommendations for the optimal management and surveillance of the disease. Currently, prophylactic surgical therapy is imperative. However, the type of surgical technique used depends mainly on the severity of the polyposis phenotype, the age of the patient at diagnosis, and a series of special clinical circumstances. Lifetime follow-up of all patients is required. This article reviews the main studies published on familial adenomatous polyposis in order to provide an update on the most appropriate management of these patients.

Surveillance and management of upper gastrointestinal disease in Familial Adenomatous Polyposis

Almost all patients affected by Familial Adenomatous polyposis (FAP) will develop foregut as well as hindgut polyps, and following prophylactic colectomy duodenal cancer constitutes one of the leading causes of death in screened populations. Without prophylactic colectomy, FAP patients predictably develop colorectal cancer, but the lifetime risk of upper gastrointestinal cancer is lower, estimated at approximately 5%. Management of the upper gastrointestinal cancer risk is one of the greatest challenges facing clinicians involved in the care of Polyposis families, and with improved survival following prophylactic colectomy, the burden of foregut disease (particularly duodenal adenomatosis) will increase. Until recently, the value of upper gastrointestinal surveillance in FAP populations has been contentious, but with improved understanding of the natural history coupled with developments in surgery, interventional endoscopy and medical therapy, treatment algorithms for duodenal adenomatosis in FAP are becoming clearer.

Estado actual del seguimiento del área gastroduodenal en la poliposis adenomatosa familiar

Familiar adenomatous polyposis (FAP) is a hereditary disease characterized by the development of multiple adenomatous polyps in the gastrointestinal tract and colorectal cancer in practically all patients who do not receive appropriate treatment. Although the most commonly involved region in this disease is the colorectal area, it is well known that adenomas can also develop in the upper gastrointestinal tract, mainly in the periampullary area of the duodenum. Because of the possibility of malignant transformation of these polyps, adequate monitoring is required, even though the optimal follow-up schedule has not yet been defined. In the present article, we report a case of a gastric adenocarcinoma detected during the follow-up of a patient diagnosed with FAP, as well as a review of the literature on this subject. We stress the need for early detection and appropriate management of this disease. Sufficient information is available to support the use of upper gastrointestinal endoscopy with lateral vision and serial biopsies of the periampullary region in these patients. The first endoscopy in patients with FAP should be performed at the age of 20 years or at diagnosis. Subsequently, a follow-up schedule should be designed, according to the number and histological characteristics of the polyps observed.

Increased Cyclooxygenase-2 Expression in Duodenal Compared with Colonic Tissues in Familial Adenomatous Polyposis and Relationship to the −765G → C COX-2 Polymorphism

BACKGROUND

Colorectal cancers arising in patients with familial adenomatous polyposis (FAP) can be largely prevented by polyp surveillance and prophylactic colectomy. As a result, duodenal adenocarcinoma has become a leading cause of death in patients with FAP. Cyclooxygenase 2 (COX-2) inhibition is effective against colorectal polyposis in FAP, but is less effective in treating duodenal polyps. We compared the expression of COX-2 in duodenal and colorectal adenomas from patients with FAP and from patients with sporadic neoplasms and correlated expression to a COX-2 promoter polymorphism (-765G/-->C) that is reported to influence COX-2 expression.

METHODS

The study population included 36 FAP patients with colonic adenomas, 22 FAP patients with duodenal adenomas, 22 patients with sporadic duodenal adenomas, and 17 patients with sporadic duodenal adenocarcinoma. Neoplastic and corresponding normal tissue COX-2 expressions were determined using immunohistochemistry on tissue microarrays. The prevalence and ethnic distribution of a polymorphism in the COX-2 promoter that influences COX-2 expression (-765G --> C) were determined in DNA from 274 individuals by real-time quantitative PCR.

RESULTS

Among patients with FAP, histologically normal duodenal mucosa showed higher COX-2 expression than normal colonic mucosa (P < 0.02), and duodenal adenomas had higher COX-2 expression than colonic adenomas (P </= 0.01). In addition, the normal duodenum of patients with FAP showed higher COX-2 expression than the normal duodenal mucosa of patients with sporadic adenomas (P < 0.05). COX-2 expression was significantly higher in the normal-appearing (P < 0.01) mucosa of patients with FAP carrying the -765GG genotype compared with those carrying the -765GC or -765CC genotypes. The -765C genotype was more common in African Americans than in Caucasians (52% versus 33%, P < 0.01).

CONCLUSIONS

High COX-2 expression in the normal and adenomatous duodenal mucosa of patients with FAP may explain the poorer response of these neoplasms to chemoprevention with COX-2 inhibitors.

Cyclooxygenase-2 inhibition in colorectal cancer: Boom or bust?

Currently, combination chemotherapy represents the standard of care treatment for patients with metastatic colorectal cancer in the United States. Despite recent improvements with the addition of biologic agents, novel treatment approaches are needed to further benefit patients. Cyclooxygenase (COX)-2 inhibition represents one such possibility. COX-2 is highly expressed in colorectal tumor neovasculature and nodal and liver metastases, and expression of COX-2 correlates with tumor stage and patient survival in selected series. COX-2 may be related to colorectal cancer development and propagation through multiple mechanisms, including stimulation of growth, migration, and invasiveness, resistance to apoptosis, and enhancement of angiogenesis. Epidemiologic data suggest nonsteroidal anti-inflammatory drugs (NSAIDs) might prevent development of colorectal cancers, and preclinical data suggest selective COX-2 inhibitors might be additive or synergistic with specific chemotherapeutic agents used in the treatment of colorectal cancer. Despite the lack of published phase I data and the limited, preliminary results of phase II studies, combinations of celecoxib and standard colorectal cancer chemotherapy have entered randomized trials. It is too early to definitively state whether COX-2 inhibition represents a major breakthrough in the treatment of colorectal cancer. Pending the results of ongoing and planned phase III studies, use of COX-2 inhibitors as single agents or incorporation of COX-2 inhibition into combined modality therapy of colorectal cancer should be limited to the setting of clinical trials.

Pylorus-preserving pancreaticoduodenectomy for advanced duodenal disease in familial adenomatous polyposis

BACKGROUND

Although only 5 per cent of patients with familial adenomatous polyposis (FAP) die from duodenal cancer, a recent study indicated that the mortality rate is much higher in patients with Spigelman stage IV disease. This has prompted an increased rate of referral for excisional surgery and an analysis of the results.

METHODS

Between January 1994 and June 2002, 16 patients with FAP (mean age 55 years; eight men) were referred to a single surgeon for pylorus-preserving pancreaticoduodenal resection for Spigelman stage IV duodenal adenomatosis.

RESULTS

One patient died from multiple organ failure after relaparotomy for haemorrhage and a jejunal perforation; other major complications included anastomotic leak (one), primary haemorrhage (one), lymphatic leak (one), chylous ascites (one), pulmonary embolus (two) and prolonged delayed gastric emptying that required total parenteral nutrition (three). Overall there were 11 major complications in eight patients. Two patients developed insulin-dependent diabetes and one postprandial dumping. Postoperative histological examination revealed five unsuspected cancers, which led to four deaths within 3 years of surgery. One patient died 2 months after surgery from pulmonary thromboembolism and another at 5 months from an inoperable brain tumour. Nine of the 16 patients were alive and well at a mean of 38 months after surgery.

CONCLUSION

The choice between continued endoscopic surveillance and excisional surgery for Spigelman stage IV duodenal disease remains finely balanced.

Surveillance and treatment of periampullary and duodenal adenomas in familial adenomatous polyposis

Patients with familial adenomatous polyposis (FAP) have a cumulative lifetime risk of over 90% for developing duodenal adenomas, which are the precursor lesions for duodenal adenocarcinoma. Consequently, these patients have a 5% to 10% lifetime risk of periampullary or duodenal adenocarcinoma, making this the leading cause of cancer death in FAP patients who have had prophylactic colectomies. The increased relative risk of duodenal carcinoma in FAP patients and the poor outcomes associated with the treatment of advanced duodenal cancer have led to the development of prevention strategies for this cancer in the setting of FAP. It is generally accepted that surveillance for duodenal adenomas and adenocarcinomas should be included in the management of patients with FAP, although there are few data from clinical trials that demonstrate the effectiveness of surveillance strategies or chemoprevention for the prevention of death from duodenal cancer. Prospective case series have shown that endoscopic surveillance with endoscopic or surgical treatment of high-risk lesions in the duodenal or periampullary region can be performed with successful removal of the at-risk lesion(s). Surveillance should begin at about 21 years of age and should be performed using both an end-viewing and a side-viewing upper endoscope. An interval of 3 to 5 years between examinations appears to be adequate if no polyposis is evident. Once polyposis develops, an interval of 1 to 3 years between screenings for mild polyposis is appropriate. Patients with denser polyposis or larger adenomas are recommended to undergo examination every 6 to 12 months because of their increased risk of developing duodenal adenocarcinoma. Nonsteroidal anti-inflammatory drug therapy with sulindac, a nonselective cyclooxygenase (COX) inhibitor, or celecoxib, a COX-2 selective inhibitor, may be of benefit after the development of duodenal polyposis by inducing the regression or stabilization of the polyposis, although there is limited evidence from randomized, controlled trials to support its routine use. Almost all cases of adenocarcinoma occur in patients with advanced polyposis (Spigelman stage IV disease), and approximately 33% of this group will go on to develop adenocarcinoma if left untreated. The most definitive procedure for reducing the risk of adenocarcinoma is surgical resection of the ampulla and/or duodenum. Pancreaticoduodenectomy or pancreas-sparing duodenectomy are appropriate surgical therapies that are believed to substantially reduce the risk of developing periampullary adenocarcinoma. However, these procedures are associated with significant morbidity and mortality, including the risk of inducing desmoid tumor formation in FAP patients.

Non steroidal anti-inflammatory drugs (NSAID) and Aspirin for preventing colorectal adenomas and carcinomas

EDITORIAL NOTE

This review was split in 2012 and the review question was to be addressed according to three new protocols: (See: http://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD010267.pub2; http://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD010291.pub2; http://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD010325.pub2). These titles were withdrawn at the protocol stage in 2020 as the authors did not make any progress on the reviews. This original review will no longer be updated and may be superseded by new titles hosted by Cochrane Gut in the future.

BACKGROUND

There is evidence from experimental animals studies, prospective and retrospective observational studies that nonsteroidal anti-inflammatory drugs (NSAIDS) may reduce the development of sporadic colorectal adenomas (CRAs) and cancer (CRC) and may induce the regression of adenomas in familial adenomatous polyposis (FAP).

OBJECTIVES

To conduct a systematic review to determine the effect of NSAIDS for the prevention or regression of CRAs and CRC.

SEARCH STRATEGY

Randomized controlled trials (RCTs) up to September 2003 were identified.

SELECTION CRITERIA

NSAIDS and aspirin (ASA) were the interventions. The primary outcomes were the number of subjects with at least one CRA, the change in polyp burden, and CRC. The secondary outcome was adverse events.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality. Dichotomous outcomes were reported as relative risks (RR) with 95% confidence intervals (CI). The data were combined with the random effects model if clinically and statistically reasonable.

MAIN RESULTS

Nine trials with 150 familial adenomatous polyposis (FAP) and 24,143 population subjects met the inclusion criteria. The interventions included sulindac, celecoxib, or aspirin (ASA). From the combined results of three trials, significantly fewer subjects in the low dose ASA group developed recurrent sporadic CRAs [RR 0.77 (95% CI 0.61, 0.96), (NNT 12.5 (95% CI 7.7, 25)] after one to three years. In another three trials, phenotypic FAP subjects that received sulindac or celecoxib had a greater proportional reduction (range: 11.9% to 44%) in the number of CRAs compared to those in the control group (range: 4.5% to 10%). There was no significant difference for the outcomes of CRC or adverse events in any of the trials.

REVIEWERS' CONCLUSIONS

There was evidence from three pooled RCTs that ASA significantly reduces the recurrence of sporadic adenomatous polyps after one to three years. There is evidence from short-term studies to support regression, but not elimination or prevention of CRAs in FAP.

Cyclooxygenase-2 Inhibitors in Lung Cancer

Prostanoids produced by the arachidonic acid pathway play an important role in multiple stages of carcinogenesis and progression of cancer. Cyclooxygenase (COX), which exists in 2 isoforms, is the rate-limiting enzyme in the COX pathway. Cyclooxygenase-1 is constitutively expressed in normal tissues and is essential for several important physiologic functions. Cyclooxygenase-2 is selectively overexpressed in neoplastic and inflammatory tissues. Non-small-cell lung cancer (NSCLC), especially adenocarcinomas, overexpress COX-2, which contributes to the progression of malignancy by several mechanisms. This represents the basis of therapy with COX-2 inhibitors. Cyclooxygenase-2 inhibitors, which are currently in clinical use for the management of inflammatory arthritis, are well tolerated by patients. They exhibit anticancer activity by several mechanisms including induction of apoptosis, inhibition of angiogenesis, and decreased invasiveness and metastatic potential. These effects have been documented in several preclinical studies. Clinical efficacy of COX-2 inhibitors in the treatment of NSCLC is presently undergoing evaluation.

The influence of mutation site and age on the severity of duodenal polyposis in patients with familial adenomatous polyposis

BACKGROUND

The present study was undertaken to identify factors affecting the severity of the duodenojejunal polyposis in patients with familial adenomatous polyposis.

METHODS

Duodenojejunal polyposis was evaluated in 41 consecutive patients with familial adenomatous polyposis (mean age 41 years, range 21-63 years), 33 (80%) with known APC mutation, by using a standardized endoscopic protocol. The severity of the polyposis was graded with the Spigelman scoring system (0-12 points), the Spigelman score/age ratio, and the presence or absence of advanced adenomas (>1 cm in diameter and/or high-grade dysplasia).

RESULTS

The Spigelman score (median 8, range 3-12) was higher in patients older than 50 years (median 10, range 3-12) as compared with younger patients (median 7.5, range 3-11; p = 0.043). A significant association between age and the presence of advanced adenomas was also observed. Patients with a mutation in the central part of the APC gene (codons 279-1309) had a higher Spigelman score and Spigelman score/age ratio as compared with patients with other mutations: median Spigelman score/age ratio 0.21 (range 0.14-0.40) versus 0.10 (range 0.06-0.20) (p < 0.001).

CONCLUSIONS

Older age and APC mutation in the central part of the gene are risk factors for the development of severe duodenojejunal polyposis.

Randomized, placebo-controlled trial of gastric acid-lowering therapy on duodenal polyposis and relative adduct labeling in familial adenomatous polyposis

PURPOSE

Bile has been implicated in the pathogenesis of duodenal polyps in patients with familial adenomatous polyposis. In vitro experiments have shown that familial adenomatous polyposis bile is capable of producing DNA adducts. This effect can be ameliorated by increasing the pH of the incubate. The aim of this double-blind randomized placebo-controlled trial was to examine the effect of oral ranitidine on duodenal polyposis in a group of patients with familial adenomatous polyposis.

METHODS

Twenty-six patients with familial adenomatous polyposis were randomly assigned to ranitidine 300 mg daily or placebo for six months after baseline endoscopy. Polyp counts were performed and biopsy specimens taken to detect DNA adducts by 32P-postlabeling.

RESULTS

No difference was seen in polyp numbers (P = 0.9) or relative adduct labeling (P = 0.7) after treatment with ranitidine or placebo.

DISCUSSION

Acid suppression therapy does not seem to improve duodenal polyposis despite in vitro findings. On the other hand, ranitidine does not exacerbate actual (or markers of) neoplasia in this highly tumor-prone condition.

Upper gastrointestinal disease in patients with familial adenomatous polyposis

BACKGROUND

Upper gastrointestinal disease has become an important aspect in the management of patients with familial adenomatous polyposis (FAP).

METHODS

A review of the literature was carried out using Medline. Epidemiology, pathology and treatment options are considered.

RESULTS AND CONCLUSION

Despite the fact that over 90 per cent of patients with FAP develop duodenal adenomas, only 5 per cent go on to develop cancer. In the absence of methods to detect who is at risk of cancer, all patients undergo regular endoscopic surveillance at present. Chemoprevention in the form of drug therapy may be the answer to controlling the disease.