Preventive surgery for colon cancer in familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer syndrome

Polyp Progression in Paediatric Patients With Familial Adenomatous Polyposis: A Single-centre Experience

OBJECTIVES

Prophylactic colectomy at a premalignant stage is the cornerstone of management of familial adenomatous polyposis (FAP). Before surgery, colonoscopy surveillance is recommended in children with FAP. This study aimed to examine the natural history of FAP in children by evaluating adenoma progression and factors influencing timing of colectomy.

METHOD

Patients with FAP younger than 18 years at first surveillance colonoscopy and who had undergone more than 1 colonoscopy were identified. Demographic, endoscopic, genetic, and surgical data were retrieved. Cumulative adenoma (polyp) counts were obtained while accounting for any polypectomies during the study period. The rate of polyp progression and factors influencing the timing of colectomy were evaluated.

RESULTS

Eighty-four patients (50% boys; mean age at first colonoscopy 13 years [standard deviation 1.97]) were identified, of which 83 had a family history of FAP. At first colonoscopy, 67 (79%) had <100 adenomas and 29 (35%) had colonic polyps identified despite rectal sparing. The median rate of polyp progression per patient was 12.5 polyps/year (range 0-145). Of the 45 (54%) patients who had undergone surgery, 41 (91%) underwent colectomy with ileorectal or ileodistal sigmoid anastomosis. Polyp progression did not alter the choice of surgical intervention in any patient.

CONCLUSION

Our results suggest that adenoma number remains relatively stable in the majority of children under surveillance. Tailored surveillance intervals according to phenotype are a more appropriate strategy as recommended by recently published guidelines.

MAPK-mediated upregulation of fibrinogen-like protein 2 promotes proliferation, migration, and invasion of colorectal cancer cells

Fibrinogen-like protein 2 (FGL2) has been reported to play a key role in the development of human cancers. However, it is still unmasked whether FGL2 plays a potential role in colorectal carcinogenesis. In this study, the messenger RNA and protein expression levels were measured by quantitative real-time polymerase chain reaction and western blot. Cell counting kit-8 assay, transwell migration, and invasion assay were carried out to evaluate the proliferation, migration, and invasion of LOVO and SW620 cells. FGL2 was upregulated in colorectal cancer (CRC) tissues, as well as cell lines. Mitogen-activated protein kinase (MAPK) signaling was activated in CRC tissues and cell lines. FGL2 was confirmed to be downregulated by MAPK signaling inhibitor U0126. Further, we determined that knockdown of FGL2 caused a reduction of proliferation, migration, and invasion in LOVO and SW620 cells. Consistently, treatment of LOVO and SW620 cells with U0126 led to a decrease in cell proliferation, migration, and invasion. However, these changes initiated by U0126 were abolished by FGL2 overexpression. To conclude, MAPK-mediated upregulation of FGL2 promotes the proliferation, migration, and invasion of CRC cells.

Dual gene deficient models of ApcMin/+ mouse in assessing molecular mechanisms of intestinal carcinogenesis

The Apc^Min/+ mouse, carrying an inactivated allele of the adenomatous polyposis coli (Apc) gene, is a widely used animal model of human colorectal tumorigenesis. While crossed with other gene knockout or knock-in mice, these mice possess advantages in investigation of human intestinal tumorigenesis. Intestinal tumor pathogenesis involves multiple gene alterations; thus, various double gene deficiency models could provide novel insights into molecular mechanisms of tumor biology, as well as gene-gene interactions involved in intestinal tumor development and assessment of novel strategies for preventing and treating intestinal cancer. This review discusses approximately 100 double gene deficient mice and their associated intestinal tumor development and progression phenotypes. The dual gene knockouts based on the Apc mutation background consist of inflammation and immune-related, cell cycle-related, Wnt/β-catenin signaling-related, tumor growth factor (TGF)-signaling-related, drug metabolism-related, and transcription factor genes, as well as some oncogenes and tumor suppressors. Future studies should focus on conditional or inducible dual or multiple mouse gene knockout models to investigate the molecular mechanisms underlying intestinal tumor development, as well as potential drug targets.

Gastrointestinal tract carcinoma in pediatric and adolescent age: The Italian TREP project experience

BACKGROUND

Gastrointestinal (GI) carcinomas are very rare in the pediatric and adolescent age range. We report the clinical features, treatment, and outcome of a series of children and adolescents with GI carcinoma prospectively registered in the Italian Tumori Rari in Età Pediatrica (TREP) project.

METHODS

The TREP project developed diagnostic and therapeutic guidelines based on recommendations currently in use for adults. Clinical data were centrally registered and reviewed.

RESULTS

Fifteen patients were registered over the years 2000-2016. Most of the tumors were colorectal carcinomas (12 cases). All but one patient had advanced-stage disease (American Joint Committee on Cancer stages III-IV), and the majority of patients had aggressive histological subtypes, i.e. poorly differentiated (G3) (five patients), mucinous (four patients), and signet ring (two patients) adenocarcinomas. Surgery was performed in 13 of 15 patients, and was radical in nine of 13 patients. Only one patient received postoperative radiotherapy. All patients received chemotherapy, with the addition of bevacizumab in two cases. Nine patients were still alive at the time of the present report, but two of them had only just completed their treatment program and one patient is still on treatment. Six patients died due to disease progression.

CONCLUSIONS

This prospective report on pediatric GI tract carcinomas confirms the rarity and biological aggressiveness of these diseases in pediatric and adolescent age. Further prospective studies are needed to explore the distinct biology of tumor in this age group in order to find new therapeutic targeted agents.

Wireless capsule endoscopy in adolescents with familial adenomatous polyposis

Aims and background

Guidelines for surveillance in patients with familial adenomatous polyposis (FAP) recommend mutation carriers to undergo periodic colorectal examination starting in the early teens. Performing colonoscopy in children may lead to complications. Wireless capsule endoscopy (WCE) has been introduced recently to evaluate both the upper and lower gastrointestinal tract, and seems suitable as a first screening examination for adolescents. The aim of this study was to evaluate the pros and cons of WCE.

Methods

This was a retrospective review of a single institution database of adolescent patients with FAP identified through the Hereditary Colorectal Tumor Registry between 2007 and 2013. The main outcomes were identification of upper and lower gastrointestinal tract polyps, tolerance of the examination, and number and size of polyps.

Results

Of 46 adolescent patients with FAP, 14 (30.4%) patients carrying adenomatous polyposis coli gene ( APC) mutation, 6 male and 8 female, age (median, range) 12 (10-17) years, body mass index 19 (13-24), underwent WCE as first screening examination. The examination was completed in 13 patients (93.3%). Wireless capsule endoscopy identified the duodenal papilla in 4 patients and colonic and rectal polyps in all 13 patients. In 7 patients, fewer than 25 polyps were identified. No complications were recorded related to the use of the video capsule.

Conclusions

Wireless capsule endoscopy is feasible and well-tolerated as a first screening examination in adolescent patients. It cannot be used as alternative to the colonoscopy, but could improve compliance with colonoscopy, and increase early adherence to a surveillance program.

Proctocolectomy for colorectal cancer--is the ileal pouch anal anastomosis a safe alternative to permanent ileostomy?

PURPOSE

Ileal pouch anal anastomosis (IPAA) is the procedure of choice in patients requiring surgery for ulcerative colitis (UC) and familial adenomatous polyposis (FAP). There are few data on reconstruction with the IPAA in patients with colorectal cancer (CRC). This study assessed the outcomes of the IPAA compared to proctocolectomy and permanent ileostomy (PI) on these patients.

METHODS

Between 1983 and 2013, over 2800 patients with CRC have been treated at the Mount Sinai Hospital (MSH). Demographic, surgical, pathological, and outcome data for all patients have been maintained in a database-73 patients were treated for CRC with proctocolectomy: 39 patients with IPAA and 34 patients with PI. Clinical features, pathologic findings, and survival outcomes were compared between these groups.

RESULTS

Each group was similar with respect to gender, stage, and histologic grade. Patients undergoing IPAA were significantly younger. The diagnosis leading to proctocolectomy was more commonly UC or FAP in patients treated with IPAA (39/39 vs. 23/34, p = 0.001). Rectal cancer subgroups were similar in age, sex, TNM stage, T-stage, height of tumor, and histologic grade. There was no significant difference in overall or disease free survival between groups for colon or rectal primaries. Analysis using the Cochran-Armitage trend test suggests that utilization of IPAA has increased over time (p = 0.002).

CONCLUSIONS

The IPAA is a viable and safe option to select for patients who would otherwise require PI. Increased experience and improved outcomes following IPAA has led to its more liberal use in selected patients.

Segmental versus extended resection for sporadic colorectal cancer in young patients

BACKGROUND AND OBJECTIVES

Guidelines on the management of colon cancer state that extensive colectomy should be "considered" for patients of young age (<50). This study aimed to compare the risk of metachronous cancer, overall recurrence and mortality between segmental and extended colon resections in patients under the age of 50 with sporadic CRC.

METHODS

We performed a retrospective review of patients age <50 undergoing surgery for CRC from 1991 to 2009. Patients were divided into two groups based on extent of resection: segmental versus extended. The primary outcomes analyzed were metachronous tumors, disease recurrence, and overall survival.

RESULTS

Two hundred seventy one patients underwent segmental resection and 30 underwent extended resection. 3.3% in the segmental resection group developed metachronous CRC versus 0% in the extended resection group (P = 0.61). There was no significant difference in the risk of recurrence or mortality for those who underwent a segmental resection compared to those with an extended resection. In a regression model, type of surgery was not an independent risk factor for recurrence or mortality.

CONCLUSIONS

Extended colectomy for sporadic CRC in patients younger than 50 does not improve disease-free or overall survival. Further study to determine if segmental resection is appropriate oncologic treatment is warranted.

Is laparoscopic surgery an option to support prophylactic colectomy in adolescent patients with Familial Adenomatous Polyposis (FAP)?

BACKGROUND

Prophylactic surgery is still considered the standard treatment for patients with Familial Adenomatous Polyposis (FAP). Laparoscopic (Lap) surgery has been introduced as an alternative approach. The aim was to evaluate the feasibility and short- to long-term outcomes after prophylactic FAP surgery in adolescent.

PROCEDURES

A retrospective review of a database of adolescent patients with FAP identified through the Hereditary Colorectal Tumor Registry in a single Institution between 2005 and 2011. Patients underwent Lap total colectomy (TC) with ileo-rectal anastomosis (IRA) or proctocolectomy (PC) with ileal-pouch anal anastomosis (IPAA). The main outcomes were: Hospital stay, postoperative complications, desmoid tumor rates, tumor recurrence, long-term complications.

RESULTS

Sixteen consecutive patients with median age 16 (range 13-19) and median BMI 22 (17-29) underwent surgery. [correction made here after initial online publication]. Of them 14 patients had LAP TC with IRA and 2 had PC with IPAA. Operative time (median, range) was TC/IRA 270 (210-330) minutes; PC/IPAA 370 (360-380) minutes. Length of extraction site was cm (median, range) 6(5-8). Lymph Node harvest (median, range) 81 (32-139). Postoperative stay days (median, range) were 6 (4-24). Five patients (31.2%) showed dysplasia on the pathological report and 3 of them showed severe dysplasia. Median follow-up time (FU) was 39 months, range (10-82). The anastomotic leak rate for 30 days was 2 (12.5%). Pouch failure was 0. Post-surgical desmoid tumors rate was 1 (6.2%) and there was no tumor recurrence. Anastomotic stricture, SBO and mortality were zero.

CONCLUSIONS

Lap approach is feasible and shows acceptable postoperative outcomes. Lap surgery can be an appealing alternative for prophylactic surgery in adolescent FAP patients. Pediatr Blood Cancer 2012; 59: 1223-1228. © 2012 Wiley Periodicals, Inc.

Surgery for colonic cancer in HNPCC: total vs segmental colectomy

AIM

The high reported risk of metachronous colon cancer (MCC) in hereditary nonpolyposis colorectal cancer (HNPCC) has led some authors to recommend total colectomy (TC) as the preferred operation for primary colon cancer, but this remains controversial. No previous study has compared survival after TC with segmental colectomy (SC) in HNPCC. The aim of this study was to determine the risk of developing MCC in patients with genetically proven HNPCC after SC or TC for cancer, and to compare their long-term survival.

METHOD

This is a prospective cohort study of all patients referred to our unit between 1995 and 2009 with a proven germline mismatch repair gene defect, who had undergone a resection for adenocarcinoma of the colon with curative intent. All patients were offered annual endoscopic surveillance.

RESULTS

Of 60 patients in the study, 39 had TC as their initial surgery and 21 had SC. After 6 years follow up, MCC occurred in eight (21%) SC patients and in none of the TC patients (P = 0.048). The risk of developing MCC after SC was 20% at 5 years. Colorectal cancer-specific survival was better in TC patients (P = 0.048) but overall survival of the two groups was similar (P = 0.29).

CONCLUSION

Patients with HNPCC have a significant risk of MCC after SC. This is eliminated by performing TC as the primary operation for colonic cancer.

Patient and tumor characteristics may raise clinicians' awareness of familial colorectal cancer: a Norwegian population-based study

BACKGROUND

The aim of this study was to identify patient and tumor characteristics that may be useful for clinicians in the identification of possible familial colorectal cancer (CRC).

METHODS

Among 562 unselected, consecutively diagnosed colorectal cancer patients, 490 patients were included and divided into familial or sporadic CRC based on family history data collected by standardized patient interviews. Clinical data were collected from the patients' medical records. Patients were classified as familial CRC according to currently accepted family history criteria. Each patient was also classified according to Amsterdam II criteria and the 4th and 5th criteria in the Revised Bethesda Guidelines that address information on family history. Tumors were described by location and histopathology; 316 tumors were examined by molecular analyses.

RESULTS

Right-sided colonic tumors and synchronous CRC tumors were associated with familial CRC, and patients with metachronous CRC or Lynch syndrome-related tumors were more likely to be classified as familial CRC. The patients' age at diagnosis did not differ between the groups. Other patient or tumor characteristics were not associated with familial CRC.

CONCLUSION

CRC patients with right-sided colonic cancers, synchronous cancers and previous CRC and/or LS-related tumors were more likely to have familial CRC, and young age at diagnosis was not associated with familial CRC in these data. A detailed family history of colorectal cancer is essential in the identification of patients and families with familial CRC.

Attenuated familial adenomatous polyposis: results from an international collaborative study

AIM

The study aimed to describe genetical and clinical features of attenuated familial adenomatous polyposis (AFAP) and to propose clinical criteria and guidelines for treatment and surveillance.

METHOD

A questionnaire study was carried out of polyposis registries with data on patients with presumed AFAP, defined as having ≤ 100 colorectal adenomas at age ≥ 25.

RESULTS

One hundred and ninety-six patients were included. The median number of adenomas was 25 (0-100) with a uniform distribution of colorectal adenomas and carcinomas (CRC). Age at CRC diagnosis was delayed by 15 years compared with classic FAP. Eighty-two patients had a colectomy and an ileorectal anastomosis and 5/82 (6%) had a secondary proctectomy. The location of the mutation in the APC gene was known in 69/171 (40%) tested patients. Only 15/29 (52%) of mutations in APC were found in parts of the gene usually associated with AFAP (the 5' end, exon 9 and 3' end).

CONCLUSIONS

A subset of FAP patients with a milder phenotype does exist and treatment and surveillance had to be modified accordingly. The mutation detection rate is lower than in classic FAP and mutations in AFAP patients are located throughout the APC gene. We propose the following clinical diagnostic criteria for AFAP: a dominant mode of inheritance of colorectal adenomatosis and <100 colorectal adenomas at age 25 or older. Colonoscopy had to be preferred to sigmoidoscopy and surveillance had to be life-long. In the majority of patients, prophylactic colectomy and ileorectal anastomosis are recommended at the age of 20-25 years.

Evaluation of 28 years of surgical treatment of children and young adults with familial adenomatous polyposis

BACKGROUND

In this retrospective study, 28 years of surgical treatment of children and young adults with familial adenomatous polyposis (FAP) was analyzed.

METHODS

Forty-three patients were operated on before the age of 26 years. Endoscopic aspects, operative data, and complications were analyzed, and the resection specimens were reevaluated. Functional outcome was assessed by telephone questionnaire.

RESULTS

Primary ileorectal anastomosis (IRA) was performed in 34 patients with a mean age of 16 years (range, 7-25 years). Primary ileal-pouch anal anastomosis (IPAA) was performed in 9 patients at a mean age of 19 years (range, 15-24 years). Secondary excision of the rectum was performed in 7 patients. Overall, rectal carcinoma was present in 4 patients, at the age of 35, 36, 37, and 38 years. Two patients, aged 39 and 40 years, died because of invasive carcinoma with distant metastasis. The functional outcome and postoperative complications after both procedures were similar to those described in literature for children with FAP. Most patients did not experience alterations in lifestyle, and there was no urinary incontinence.

CONCLUSIONS

In this retrospective study, both IRA and IPAA showed to be feasible techniques in young patients with FAP. A prospective study with a sufficient follow-up is needed to compare both techniques in this specific group of patients.

Ten years after mutation testing for Lynch syndrome: cancer incidence and outcome in mutation-positive and mutation-negative family members

PURPOSE

Colonoscopies with polypectomies and endometrial biopsies with transvaginal ultrasonography, repeated at 2- to 3-year intervals, are performed for prevention or early detection of cancer in patients with DNA mismatch repair gene mutation causing Lynch syndrome. The long-term effectiveness of surveillance was evaluated in Lynch syndrome family members tested approximately 10 years ago.

MATERIALS AND METHODS

Cancer incidence and survival were determined after an 11.5-year follow-up in 242 mutation-positive and 367 mutation-negative participants. These participants in 57 Lynch syndrome families with 14 different mutations were at 50% risk. The median age was 36 years (range, 18 to 72 years) in mutation carriers and 42 years (range, 18 to 72 years) in mutation-negative participants, and none had had cancer of the Lynch syndrome type.

RESULTS

Compliance was 95.9% for the colonic surveillance and 97.1% for the gynecologic surveillance. Colorectal cancer (CRC) occurred in 30 mutation-positive participants, and 74 participants had adenomas removed. Three patients died of CRC. Endometrial cancer (EC) occurred in 19 of 103 women at risk, and 48 women had prophylactic hysterectomy. Six of 112 women at risk had ovarian cancer. The overall cancer risk ratio (RR) in mutation carriers was 5.80 (95% CI, 3.4 to 9.5). Cancer mortality rate (RR = 2.28; 95% CI, 0.82 to 6.31) and overall death rate (RR = 1.26; 95% CI, 0.65 to 2.46) were not significantly increased.

CONCLUSION

Long-term compliance in surveillance for CRC and EC exceeded 95% in Lynch syndrome. All CRC deaths were not prevented as a result of noncompliance or missed lesions. Still, after 10 years of surveillance, no significant increase in mortality had occurred compared with mutation-negative relatives.

Prevalence and outcome of anemia after restorative proctocolectomy: a clinical literature review

PURPOSE

Iron and/or vitamin B12 deficiency anemias, which have adverse effects on patients' quality of life, are commonly observed and often overlooked complications after restorative proctocolectomy. We performed a systematic review of publications on the prevalence of anemia as well as on the impact of anemia on a range of clinical, functional, quality of life, and economic outcomes in restorative proctocolectomy patients. This information is important to help healthcare providers through a comprehensive overview to increase awareness about a condition that could require therapy to improve patient healthcare and quality of life.

METHODS

We reviewed the English language publications on the incidence of anemia and its adverse effect after restorative proctocolectomy The United States National Library of Medicine database (MEDLINE), the Excerpta Medica database (EMBASE), the Cochran Library, and the Google search engine were searched for published articles on the prevalence and impact of anemia in post-restorative proctocolectomy surgical patients.

RESULTS

The long-term complication most frequently described after RPC is pouchitis. Pouchitis is significantly associated with iron deficiency anemia caused by pouch mucosal bleeding. Other causes are insufficient and/or impaired iron absorption. It has also been observed, however, that restorative proctocolectomy patients with underlying familial adenomatous polyposis rarely develop pouchitis yet show higher rates of iron deficiency anemia compared to those patients with underlying ulcerative colitis. Other causes shown as independent risk factors for iron deficiency anemia in restorative proctocolectomy patients are malignancy, desmoid tumors, and J-pouch configuration. Vitamin B12 deficiency anemia is also common after restorative proctocolectomy. About one-third of restorative proctocolectomy patients show abnormal Schilling test and 5 percent have low referenced serum cobalamin. It has been observed that the degree resection of the terminal-ileum, malabsorption, bacterial overgrowth, and dietary factors are among the known causes of cobalamin deficiency. Folate deficiency has not been reported in restorative proctocolectomy patients. Describing restorative proctocolectomy surgery and its outcomes, in patients without anemia, the quality of life is reported excellent regardless of operative technique.

CONCLUSIONS

Anemia is not uncommon following restorative proctocolectomy and has been shown to have negative effects on the patient's quality of life and the economy and may substantially increase healthcare costs. The treatment of anemia and its underlying causes is important to improving clinical and economic outcomes.

Surveillance colonoscopy improves survival in a cohort of subjects with a single mismatch repair gene mutation

OBJECTIVE

Previous studies have shown a benefit for surveillance colonoscopy in heterogeneous groups of subjects with suspected or proven hereditary nonpolyposis colon cancer. The aim of this study was to investigate whether surveillance colonoscopy improves the survival in subjects who all carry a single mismatch repair gene defect.

METHOD

This is a prospective cohort study of 178 subjects who carry a mutation of the MLH1 gene in exon 13 (C1528T). They were offered surveillance colonoscopy between 1988 and 2006, and were followed up until September 2007.

RESULTS

One hundred and twenty-nine subjects underwent surveillance colonoscopy, and 49 declined. After a median follow up of 5 years, colorectal cancer was diagnosed in 14/129 (11%) subjects in the surveillance group and 13/49 (27%) in the nonsurveillance group (P = 0.019). Cancers in the surveillance group were at an earlier stage than in the nonsurveillance group (P = 0.032). Death from colorectal cancer occurred in three of 129 (2%) subjects in the surveillance group, and six of 49 (12%) in the nonsurveillance group (P = 0.021). The Kaplan-Meyer estimates for median survival from birth were 78 years in the surveillance group, and 55 years in the nonsurveillance group (P = 0.024). The Kaplan-Meyer estimates for median colorectal cancer-free survival from birth were 73 years in the surveillance group and 47 years in the nonsurveillance group (P = 0.0089).

CONCLUSION

Surveillance colonoscopy was associated with improved overall and colorectal cancer-related survival in subjects carrying a single mismatch repair gene mutation.

Development of colorectal tumors in colonoscopic surveillance in Lynch syndrome

BACKGROUND & AIMS

Mutation carriers in Lynch syndrome families have a high risk for developing colorectal cancer during their lifetime. This study was designed to assess the cumulative risk for the development of colorectal adenoma or carcinoma in prospective colonoscopic surveillance.

METHODS

Data from the Finnish Hereditary Colorectal Cancer Registry electronic database on 420 Lynch syndrome mutation carriers without previous colorectal tumors were reviewed. Between March 1982 and May 2005 the mutation carriers underwent a total of 1252 colonoscopies. The total follow-up time was 3150 years (mean, 6.7 y/patient).

RESULTS

The cumulative risk of adenoma by age 60 was estimated as 68% (95% confidence interval [CI], 50%-80%) in men and 48% (95% CI, 29%-62%) in women. The estimated cumulative risk up to age 60 years for the development of cancer found as a result of surveillance at an interval of 2-3 years was 35% (95% CI, 16%-49%) in men and 22% (95% CI, 7%-34%) in women. Half of the adenomas were located proximal to the splenic flexure. Extracolonic cancer was diagnosed in 73 patients (18%).

CONCLUSIONS

Adenoma would appear to be the most important lesion preceding cancer formation in Lynch syndrome and removal of adenomas decreases the risk for colorectal cancer (CRC). The Finnish surveillance protocol of colonoscopies at 2- to 3-year intervals facilitates patient adherence but includes an essential risk for CRC up to 60 years of age, but without CRC-related mortality when the surveillance instructions are followed.

The surgeon's role in cancer prevention. The model in colorectal carcinoma

Cancer Prevention is an emerging field, capturing the old traditional concept of anticipating the development of a major disease and preventing its full impact by early detection, treatment, or aborting the tumorigenic process by a "molecular vaccine" and alleviating the full impact of the disease. Surgeons are important clinician scientists who can carry this discipline forward and develop its full potential in the clinics and in the community. Advances in molecular biology, genetics, and other technologies have permitted seminal understanding of the carcinogenic pathways and identification of targets and intermediate end points in neoplasia. In this review, we will see that we have the means of preventing significant numbers of colorectal carcinomas (CRC).

Restorative proctocolectomy and ileal pouch-anal anastomosis for familial adenomatous polyposis revisited

Since restorative proctocolectomy (RPC) with ileal-pouch anal anastomosis (IPAA) removes the entire diseased mucosa, it has become firmly established as the standard operative procedure of choice for familial adenomatous polyposis (FAP). Many technical controversies still persist, such as mesenteric lengthening techniques, close rectal wall proctectomy, endoanal mucosectomy vs. double stapled anastomosis, loop ileostomy omission and a laparoscopic approach. Despite the complexity of the operation, IPAA is safe (mortality: 0.5-1%), it carries an acceptable risk of non-life-threatening complications (10-25%), and it achieves good long-term functional outcome with excellent patient satisfaction (over 95%). In contrast to the high incidence in patients operated for ulcerative colitis (UC) (15-20%), the occurrence of pouchitis after IPAA seems to be rare in FAP patients (0-11%). Even after IPAA, FAP patients are still at risk of developing adenomas (and occasional adenocarcinomas), either in the anal canal (10-31%) or in the ileal pouch itself (8-62%), thus requiring lifelong endoscopic monitoring. IPAA operation does not jeopardise pregnancy and childbirth, but it does impair female fecundity and has a low risk of impairment of erection and ejaculation in young males. The latter can almost completely be avoided by a careful "close rectal wall" proctectomy technique. Some argue that low risk patients (e.g. <5 rectal polyps) can be identified where ileorectal anastomosis (IRA) might be reasonable. We feel that the risk of rectal cancer after IRA means that IPAA should be recommended for the vast majority of FAP patients. We accept that in some very selected cases, based on clinical and genetics data (and perhaps influenced by patient choice regarding female fecundity), a stepwise surgical strategy with a primary IPA followed at a later age by a secondary proctectomy with IPAA could be proposed.

The genetics of HNPCC: application to diagnosis and screening

Hereditary nonpolyposis colorectal cancer syndrome (HNPCC; Lynch Syndrome) is the most common form of hereditary colorectal cancers. Predisposed individuals have increased lifetime risk of developing colorectal, endometrial and other cancers. The syndrome is primarily due to heterozygous germline mutations in one of the mismatch repair genes; mainly MLH1, MSH2, MSH6 and PMS2. The resulting mismatch repair deficiency leads to microsatellite instability which is the hallmark of tumors arising within this syndrome, as well as a variable proportion of sporadic tumors. Diagnostic guidelines and criteria for molecular testing of suspected families have been proposed and are continuously updated. However, not all families fulfilling these criteria show mutations in mismatch repair genes and/or microsatellite instability implicating other, as yet unknown, carcinogenic mechanisms and predisposition genes. This subset of tumors is the focus of current clinical and molecular research. This review addresses recent advances in the field of HNPCC research and their applications in the management of affected individuals and families.

Surveillance in Lynch syndrome

The major aim of surveillance in Lynch syndrome is to diagnose malignant or premalignant lesions at the asymptomatic stage by regular checkups, particularly in the large bowel. Therefore, screening for colorectal adenomas and carcinomas by regular colonoscopies is the main topic of the present review. However, it should be remembered, that primary prevention - whether through the use of chemoprevention or the promotion of a healthy life-style may form a significant part of such surveillance in the future. Observational studies indicate that the adenoma carcinoma sequence is the main pathway in the development of colorectal cancer in Lynch syndrome. A colonoscopy every 1-3 years starting at age 20 to 25 years and the removal of observed adenomas is recommended for individuals known to have Lynch syndrome associated mutations. The incidence of colorectal cancer in family branches screened this way is lower than that in past unscreened generations. The screening of other malignancies associated with Lynch syndrome is more complex. Screening for endometrial cancer has recommended previously, but no benefits have been shown in recent studies. The value of screening for other extracolonic cancers remains also uncertain.

Prophylaktische Chirurgie der familiären adenomatösen Polyposis coli

Familial adenomatous polyposis coli (FAP) may not be considered a single disease entity with standardized guidelines for operative treatment. However, prophylactic colectomy after the manifestation of polyps but prior to the development of colorectal cancer is essential. The optimal timing of prophylactic surgery remains a clinical decision taken independently of mutation analysis. In case of the classic FAP phenotype, restorative proctocolectomy and ileal pouch-anal anastomosis is the procedure of choice. The development of reliable guidelines for attenuated FAP variants requires further evidence from clinical studies on surgical strategy and the advantages of prophylactic surgery over regular endoscopic screening with removal of polyps.

SISE matters: the Sum of Information on Seventy-yr-old Equivalents measures pedigree information content when assessing the risk of HNPCC in a family

Hereditary non-polyposis colon cancer (HNPCC) is a significant cause of colorectal and other malignancies. Due to the lack of features that reliably differentiate between a sporadic case and an inherited case of colon cancer, it is likely that HNPCC is under reported. The diagnosis of HNPCC relies heavily on finding multiple cases of colorectal or other specific cancers within a family. In the absence of a significant family history, a diagnosis of HNPCC is seldom considered. We postulate that small kinships--or, more specifically, kinships with a low information content--are more likely to be designated as having a low risk of an inherited cancer predisposition than are large kinships. This has the potential to exacerbate the under-diagnosis of HNPCC in small families, leading to inadequate treatment, follow-up and family counselling. We have developed an objective measure of the information content of individual pedigrees called the Sum of Information on Seventy-yr-old Equivalents (SISE) coefficient. The SISE coefficient is a function of the number of relatives in a kinship and their relationship to the proband, of their ages and of the age-dependent penetrance of HNPCC mutations. A population-based series of colorectal cancer cases was assessed, by currently accepted methods, for the likelihood of there being an HNPCC mutation segregating in each family. We observed that families with a low SISE coefficient were significantly more likely to be designated at low risk of HNPCC (P< or =0.001). Using a cumulative binomial distribution function, we estimated the likelihood of observing multiple cancers in families of different SISE coefficients.

Lynch syndrome: implications for the surgeon

Hereditary nonpolyposis colorectal cancer (HNPCC), or Lynch syndrome, is an autosomal dominant syndrome characterized by onset of colorectal cancer (CRC) at an early age, right-sided predominance, excess synchronous and metachronous colorectal neoplasms, and extracolonic neoplasms. It is the most common of the hereditary CRCs, so the practicing surgeon should expect to encounter patients with this disease. The diagnosis of HNPCC, which begins with a complete family history and a high index of suspicion by the clinician, has important implications in the management and surveillance of not only the affected individual but also for the individual's family. In this article, the diagnosis and management of Lynch syndrome will be reviewed, with emphasis on the implications for the surgeon.