Regular endoscopic surveillance and polypectomy is effective in managing rectal adenoma progression following colectomy and ileorectal anastomosis in patients with familial adenomatous polyposis

Development of Desmoid Tumors After Ileorectal Anastomosis Versus Ileal Pouch-Anal Anastomosis in Familial Adenomatous Polyposis

BACKGROUND & AIMS

Desmoid tumors (DT) are an important cause of morbidity and mortality in patients with familial adenomatous polyposis (FAP). DT development might be related to the type and approach of colectomy. We aimed to compare DT development after colectomy with ileorectal anastomosis (IRA) and proctocolectomy with ileal pouch-anal anastomosis (IPAA).

METHODS

We performed an international historical cohort study in patients with FAP who underwent IRA or IPAA between 1961 and 2020. The primary outcome was the incidence of abdominal DT (either mesenteric, retroperitoneal, or abdominal wall). Patients with a DT diagnosis before or at colectomy were excluded. Time to DT was considered censored at an eventual secondary proctectomy after IRA. We used multivariable Cox regression modelling to adjust for potential confounders.

RESULTS

We analyzed data from 852 patients: 514 after IRA and 338 after IPAA (median follow-up, 21 and 16 years, respectively). DTs were diagnosed in 64 IRA patients (12%) and 66 IPAA patients (20%). The cumulative DT incidence at 5 and 10 years was 7.5% and 9.3% after open IRA and 4.7% and 10.9% after laparoscopic IRA. These estimates were 13.6% and 15.4% after open IPAA and 8.4% and 10.0% after laparoscopic IPAA. The postoperative risk was significantly higher after IPAA (P < .01) in multivariable analysis, whereas approach did not significantly influence the risk.

CONCLUSIONS

The risk of developing an abdominal DT was found to be significantly higher after IPAA than after IRA. Postoperative DT risk should be taken into account when choosing between IRA and IPAA in FAP.

Endoscopic management of patients with familial adenomatous polyposis after prophylactic colectomy or restorative proctocolectomy - systematic review of the literature

BACKGROUND

Patients with familial adenomatous polyposis (FAP) develop early colorectal adenomas and if left untreated, progression to cancer is an inevitable event. Prophylactic surgery does not prevent further development of cancer in the rectal remnant, rectal cuff in patients with ileal pouch anal anastomosis (IPAA) and even on the ileal mucosa of the pouch body. The aim of this review is to assess long-term rates of cancer and adenoma development in patients with FAP after prophylactic surgery and to summarise current recommendations for endoscopic management and surveillance of these patients.

MATERIALS AND METHODS

A systematic literature search of studies from January 1946 through to June 2023 was conducted using the PRISMA checklist. The electronic database PubMed was searched.

RESULTS

Fifty-four papers involving 5010 patients were reviewed. Cancer rate in the rectal remnant was 8.8-16.7% in the western population and 37% in the eastern population. The cumulative risk of cancer 30 years after surgery was 24%. Mortality due to cancer in the rectal remnant is 1.1-11.1% with a 5-year survival rate of 55%. The adenoma rate after primary IPAA was 9.4-85% with a cumulative risk of 85% 20 years after surgery and a cumulative risk of 12% for advanced adenomas 10 years after surgery. Cumulative risk for adenomas after ileorectal anastomosis (IRA) was 85% after 5 and 100% after 10 years. Adenomas developed more frequently after stapled (33.9-57%) compared to hand-sewn (0-33%) anastomosis. We identified reports of 45 cancers in patients after IPAA of which 30 were in the pouch body and 15 in the rectal cuff or at the anastomosis.

CONCLUSIONS

There was a significant incidence of cancer and adenomas in the rectal remnant and ileal pouch of FAP patients during the long-term follow-up. Regular endoscopic surveillance is recommended, not only in IRA patients, but also in pouch patients after proctocolectomy.

Outcomes following duodenectomy in patients with familial adenomatous polyposis

Background and study aims Some patients with familial adenomatous polyposis (FAP) and extensive duodenal polyposis or cancer require total duodenectomy. Regular postoperative endoscopic surveillance of the remaining jejunum and stomach is recommended, but little is known about the outcomes after this surgery. Patients and methods Patients with FAP who underwent either pancreatoduodenectomy (PD) or pancreas-preserving total duodenectomy (PPTD) were identified at two expert centers. Data about postoperative endoscopic surveillance outcomes were collected, as well as survival outcomes. Results Overall, 119 patients (50% female) underwent duodenectomy (86 PD and 33 PPTD); 100 for benign duodenal polyposis and 19 for duodenal or ampullary cancer. Details of postoperative endoscopic surveillance were available for 88 patients (74%). During a median follow-up of 106 months, 36 patients (41%) were diagnosed with jejunal adenomas after duodenectomy, with a significantly higher proportion in patients who underwent PPTD compared with patients who underwent PD (log-rank, P < 0.01). Two patients developed jejunal cancer (2%). Twenty-six patients (30%) were diagnosed with a total of 66 gastric adenomas, of which 61% were located in the fundus/body and 39% in the antrum. Five patients (6%) developed gastric cancer after a median of 15 years (range 6-23 years), all but one within carpeting fundic gland polyposis. Patients who underwent surgery for cancer had worse survival than patients with benign disease and all but one patient with postoperative gastric/jejunal cancer died. Conclusions After duodenectomy in FAP, a considerable risk of developing adenomas and cancer in the stomach and jejunum exists with poor cancer prognosis, highlighting the need for close postoperative endoscopic surveillance.

Surgical Decision-Making in Familial Adenomatous Polyposis

Familial adenomatous polyposis (FAP) is an autosomal dominant disorder affecting patients with germline mutations of the adenomatous polyposis coli (APC) tumor suppressor gene. The surgical treatment of colorectal disease in FAP, which has the goal of colorectal cancer prevention, varies based on both patient and disease factors but can include the following: total colectomy with ileorectal anastomosis, proctocolectomy with stapled or hand-sewn ileal pouch-anal anastomosis, or total proctocolectomy with end ileostomy. The operative options and extent of resection, as well as the use of endoscopy and chemoprevention for the management of polyposis, will be discussed in detail in this article. In addition, commonly debated management decisions related to the treatment of patients with FAP, including the timing of prophylactic colorectal resections for patients with FAP and management of the polyp burden in the rectum, will be discussed. Finally, genotype considerations and the impact of desmoid disease on operative decisions in the setting of FAP will also be reviewed.

PROTACs: Current and Future Potential as a Precision Medicine Strategy to Combat Cancer

Proteolysis targeting chimeras (PROTAC) are an emerging precision medicine strategy, which targets key proteins for proteolytic degradation to ultimately induce cancer cell killing. These hetero-bifunctional molecules hijack the ubiquitin proteasome system to selectively add polyubiquitin chains onto a specific protein target to induce proteolytic degradation. Importantly, PROTACs have the capacity to target virtually any intracellular and transmembrane protein for degradation, including oncoproteins previously considered undruggable, which strategically positions PROTACs at the crossroads of multiple cancer research areas. In this review, we present normal functions of the ubiquitin regulation proteins and describe the application of PROTACs to improve the efficacy of current broad-spectrum therapeutics. We subsequently present the potential for PROTACs to exploit specific cancer vulnerabilities through synthetic genetic approaches, which may expedite the development, translation, and utility of novel synthetic genetic therapies in cancer. Finally, we describe the challenges associated with PROTACs and the ongoing efforts to overcome these issues to streamline clinical translation. Ultimately, these efforts may lead to their routine clinical use, which is expected to revolutionize cancer treatment strategies, delay familial cancer onset, and ultimately improve the lives and outcomes of those living with cancer.

Risk of Proctectomy After Ileorectal Anastomosis in Familial Adenomatous Polyposis in the Modern Era

BACKGROUND

Prophylactic surgery for familial adenomatous polyposis has evolved over several decades. Restorative proctocolectomy with IPAA provides an alternative to total abdominal colectomy with ileorectal anastomosis. We have previously shown that the rate of proctectomy and rectal cancer after total abdominal colectomy with ileorectal anastomosis in the "pre-pouch era" was 32% and 13%, respectively.

OBJECTIVE

To determine the rate of proctectomy and rectal cancer among familial adenomatous polyposis patients and relative rectal sparing (fewer than 20 rectal polyps) selected for total abdominal colectomy with ileorectal anastomosis in the modern era.

DESIGN

Retrospective cohort study.

SETTING

Single tertiary care institution with a hereditary colorectal cancer registry.

PATIENTS

Patients with familial adenomatous polyposis who underwent total abdominal colectomy with ileorectal anastomosis between 1993 and 2020.

MAIN OUTCOME MEASURES

Incidence of proctectomy for any indication and rectal cancer.

RESULTS

A total of 197 patients with a median age of 24 years (range, 10-67) were included. The median follow-up after total abdominal colectomy with ileorectal anastomosis was 13 years (interquartile range, 6-17). Sixteen patients (8%) underwent proctectomy. Indications included rectal cancer in 6 patients (3%; 2 stage I and 4 stage III), polyps with high-grade dysplasia in 4 (2%), progressive polyp burden in 3 (1.5%), defecatory dysfunction in 2 (1%), and anastomotic leak in 1 (0.5%). Among 30 patients (18%) with 20 or more rectal polyps at the time of total abdominal colectomy with ileorectal anastomosis, 8 patients (26%) underwent proctectomy and 3 patients developed rectal cancer (10%). Among 134 patients (82%) with fewer than 20 polyps, 8 patients (6%) underwent proctectomy and 3 patients developed rectal cancer (2%). Number of rectal polyps at the time of total abdominal colectomy with ileorectal anastomosis was associated with the likelihood of proctectomy (OR 1.1, p < 0.001) but not incident rectal cancer ( p = 0.3).

LIMITATION

Retrospective data collection.

CONCLUSIONS

Patients with familial adenomatous polyposis selected for total abdominal colectomy with ileorectal anastomosis by rectal polyp number have low rates of proctectomy and rectal cancer compared to historical controls. With appropriate selection criteria and surveillance, total abdominal colectomy with ileorectal anastomosis remains an important and safe treatment option for patients with familial adenomatous polyposis. See Video Abstract .

RIESGO DE PROCTECTOMA DESPUS DE ANASTOMOSIS ILEORRECTAL EN POLIPOSIS ADENOMATOSA FAMILIAR EN LA ERA MODERNA

ANTECEDENTES:La cirugía profiláctica para la poliposis adenomatosa familiar (PAF) ha evolucionado durante varias décadas. La proctocolectomía restauradora con anastomosis anal con bolsa ileal (IPAA) proporciona una alternativa a la colectomía abdominal total con anastomosis ileorrectal (TAC/IRA). Anteriormente hemos demostrado que la tasa de proctectomía y cáncer de recto después de TAC/IRA en la era "pre-bolsa" era del 32% y el 13%, respectivamente.OBJETIVO:Determinar la tasa de proctectomía y cáncer de recto entre pacientes con PAF y pacientes con preservación rectal relativa (<20 pólipos rectales) seleccionados para TAC/IRA en la era moderna.DISEÑO:Estudio de cohorte retrospectivo.ÁMBITO:Institución única de atención terciaria con un registro de cáncer colorrectal hereditario.PACIENTES:Pacientes con PAF que se sometieron a TAC/IRA entre 1993 y 2020.MEDIDAS DE RESULTADO PRINCIPALES:Incidencia de proctectomía por cualquier indicación y cáncer de recto.RESULTADOS:Se incluyeron 197 pacientes con una mediana de edad de 24 años (rango 10-67). La mediana de seguimiento tras TAC/IRA fue de 13 años (RIC 6-17). 16 pacientes (8%) fueron sometidos a proctectomía. Las indicaciones incluyeron cáncer de recto en 6 (3%) (2 en estadio I y 4 en estadio III); pólipos con displasia de alto grado en 4 (2%); carga progresiva de pólipos en 3 (1,5%), disfunción defecatoria en 2 (1%); y fuga anastomótica en 1 (0,5%). Entre 30 pacientes (18%) con ≥20 pólipos rectales en el momento de TAC/IRA, 8 pacientes (26%) se sometieron a proctectomía y 3 pacientes desarrollaron cáncer de recto (10%). Entre 134 pacientes (82%) con <20 pólipos, 8 pacientes (6%) se sometieron a proctectomía y 3 pacientes desarrollaron cáncer de recto (2%). El número de pólipos rectales en el momento de TAC/IRA se asoció con la probabilidad de proctectomía (OR 1,1, p <0,001), pero no con la incidencia de cáncer de recto (p = 0,3).LIMITACIÓN:Recopilación de datos retrospectivos.CONCLUSIÓN:Los pacientes con PAF seleccionados para TAC/IRA por el número de pólipos rectales tienen tasas bajas de proctectomía y cáncer de recto en comparación con los controles históricos. Con criterios de selección y vigilancia adecuados, TAC/IRA sigue siendo una opción de tratamiento importante y segura para los pacientes con PAF. (Pre-proofed version ).

Cancer in Patients With Familial Adenomatous Polyposis: A Nationwide Danish Cohort Study With Matched Controls

BACKGROUND & AIMS

Familial adenomatous polyposis (FAP) is a hereditary disorder that predisposes patients to colorectal cancer (CRC). Prophylactic colectomy has greatly reduced the risk of CRC. However, new associations between FAP and the risk of other cancers have subsequently emerged. In this study, we assessed the risk of specific primary and secondary cancers among patients with FAP compared with matched controls.

METHODS

All known patients with FAP up until April 2021 were identified in the nationwide Danish Polyposis Register and paired with 4 unique controls matched by birth year, sex, and postal code. The risk of overall cancers, specific cancer types, and risk of a second primary cancer was assessed and compared with controls.

RESULTS

The analysis included 565 patients with FAP and 1890 controls. The overall risk of cancer was significantly higher for patients with FAP than for controls (hazard ratio [HR], 4.12; 95% confidence interval [CI], 3.28-5.17; P < .001). The increased risk was mainly due to CRC (HR, 4.61; 95% CI, 2.58-8.22; P < .001), pancreatic cancer (HR, 6.45; 95% CI, 2.02-20.64; P = .002), and duodenal/small-bowel cancer (HR, 14.49; 95% CI, 1.76-119.47; P = .013), whereas no significant difference was observed for gastric cancer (HR, 3.29; 95% CI, 0.53-20.23; P = .20). Furthermore, the risk of a second primary cancer was significantly higher for patients with FAP (HR, 1.89; 95% CI, 1.02-3.50; P = .042). Between 1980 and 2020, the risk of cancer among patients with FAP decreased by ∼50%.

CONCLUSIONS

Despite an absolute reduction in the risk of developing cancer among patients with FAP, the risk remained significantly higher than for the background population due to colorectal, pancreatic, and duodenal/small-bowel cancers.

An update of the variant spectrum of the APC gene in Iranian familial adenomatous polyposis patients

Familial adenomatous polyposis (FAP) is an autosomal dominant colorectal cancer syndrome that is characterized by the development of multiple adenomas in the colon and rectum with high penetrance rates. This disease has specific features like the occurrence of pathogenic variations in the APC gene and diverse FAP phenotypes due to the occurrence region. In this study we aimed to evaluate pathogenic variants in exons of the APC gene in Iranian patients with FAP. A total of 35 FAP individuals were referred to the gastroenterology ward of Taleghani Hospital. As the aim of the study was to study the germline variations in the participants, the peripheral blood was collected and after the DNA extraction, PCR, and Sanger sequencing processes for the APC gene, the results were evaluated by the ACMG classification guidelines to report their pathogenicity. Accordingly, out of eight specific detected variants, three of them were novel, and the rest were reported previously. These eight variants were all truncating protein and pathogenic, and they were limited to 849-1378 codons. Overall, detected variants revealed discrepancies and parallels with previous reported cases in terms of quantity, occurrence region, and association with demographic and clinicopathological characteristics of patients. The spectrum of detected variants and the patient's phenotype showed distinct characteristics, such as occurrence in specific regions and the absence of extracolonic symptoms like Congenital hypertrophy of the retinal pigment epithelium (CHRPE). These findings open the path to comprehending the typical symptoms, their rarity, and their occurrence in the Iranian population and also due to the facts, we found that the studying of the APC gene alone for diagnosing FAP disease is not sufficient, and considering other genes are completely rational in the case of sequencing and studying the variants.

Does an Ileoanal Anastomosis Decrease the Rate of Successful Pregnancy Compared With an Ileorectal Anastomosis? A National Study of 1491 Patients

OBJECTIVE

Report the rate of successful pregnancy in a national cohort of women with either an ileal pouch anal (IPAA) or ileorectal (IRA) anastomosis constructed after colectomy for inflammatory bowel disease (IBD) or polyposis.

BACKGROUND

Fertility after IPAA is probably impaired. All available data are corroborated by only small sample size studies. It is not known whether construction of IPAA versus IRA influences the odds of subsequently achieving a successful pregnancy, especially with increased utilization of the laparoscopic approach.

METHODS

All women (age: 12-45 y) undergoing IRA or IPAA in France for polyposis or IBD, between 2010-2020, were included. A control population was defined as women aged from 12 to 45 years undergoing laparoscopic appendicectomy during the same period. The odds of successful pregnancy were studied using an adjusted survival analysis.

RESULTS

A total of 1491 women (IPAA=872, 58%; IRA=619, 42%) were included. A total of 220 deliveries (15%) occurred during the follow-up period of 71 months (39-100). After adjustment, the odds of successful pregnancy was not significantly associated with type of anastomosis (after IPAA: Hazard Ratio [HR]=0.79, 95% confidence interval=0.56-1.11, P =0.17). The laparoscopic approach increased the odds of achieving successful pregnancy (HR=1.79, 95% confidence interval=1.20-2.63, P =0.004). IRA and IPAA significantly impacted fertility when compared with the control population ( P <0.001).

CONCLUSIONS

In this large cohort study, total colectomy for polyposis or IBD was associated with reduced fertility compared with the general population. No difference in odds of achieving successful pregnancy was found between IRA and IPAA after adjustment. This analysis suggests laparoscopic surgery may be associated with greater likelihood of pregnancy.

Current Surgical Concepts in Lynch Syndrome and Familial Adenomatous Polyposis

Background

Approximately 5% of colorectal cancers (CRCs) are associated with hereditary cancer syndromes. The natural history of these syndromes differs from sporadic cancers, and due to their increased risk of metachronous carcinomas, surgical approaches also differ. This review focuses on the current recommendations for surgical treatment and what evidence has led to these recommendations in the most clinically relevant hereditary CRC syndromes: Lynch syndrome (LS) and (attenuated) familial adenomatous polyposis (FAP).

Summary

LS has no common phenotype and is caused by individual germline variants in one of the mismatch repair genes (MLH1, MSH2, MSH6, or PMS2). Because each gene is associated with a different risk of metachronous cancer, guidelines now differentiate between genes in their recommendations for oncology interventions. Classical and attenuated FAP are caused by germline mutations in the APC gene and have a characteristic phenotype. Although correlations exist between phenotype and genotype, the indication for surgery is predominantly based on clinical manifestation rather than specific gene mutations.

Key Message

Currently, the recommendation on the two diseases tends to go in opposite directions: while some forms of FAP may require less extensive surgery, in some LS patients, more sophisticated knowledge of metachronous carcinoma risk leads to more extensive surgery.

Prevalence and Management of Cancer of the Rectal Stump after Total Colectomy and Rectal Sparing in Patients with Familial Polyposis: Results from a Registry-Based Study

BACKGROUND

The balance between quality of life and colorectal cancer risk in familial adenomatous polyposis (FAP) patients is of primary importance. A cut-off of less than 30 polyps under 1 cm of diameter in the rectum has been used as an indication for performing ileo-rectal anastomosis (IRA) in terms of lower rectal cancer risk. This study aimed to assess clinical and surgical features of FAP patients who developed cancer of the rectal stump.

METHODS

This retrospective study included all FAP patients who underwent total colectomy/IRA from 1977 to 2021 and developed subsequent rectal cancer. Patients' features were reported using descriptive statistics by considering the overall case series and within pre-specified classes of age (<20, 20-30, and >30 years) at first surgery.

RESULTS

Among the 715 FAP patients, 47 (6.57%, 95% confidence interval: 4.87; 8.65) developed cancer in the rectal stump during follow-up. In total, 57.45% of the population were male and 38.30% were proband. The median interval between surgery and the occurrence of rectal cancer was 13 years. This interval was wider in the youngest group (p-value: 0.012) than the oldest ones. Twelve patients (25.53%) received an endoscopic or minimally invasive resection. Amongst them, 61.70% were Dukes stage A cancers.

CONCLUSIONS

There is a definite risk of rectal cancer after total colectomy/IRA; however, the time interval from the index procedure to cancer developing is long. Minimally invasive and endoscopic treatments should be the procedures of choice in patients with early stage cancers.