Impact of colonoscopic screening in Familial Colorectal Cancer Type X

Public Interest Group on Cancer Research: a successful patient-researcher partnership in Newfoundland and Labrador

BACKGROUND

Partnering with patients and family members affected by cancer is essential for meaningful research, public engagement and outreach, and advocacy activities.

OBJECTIVE

Our objective was to create a public interest group through an academic-community partnership focused on cancer research and public engagement.

METHODS

A purposeful recruitment process was implemented to ensure a diverse and inclusive group. The group meets virtually and communicates by email. The group's activities focus on identifying the needs, priorities, and interests of cancer-affected individuals in the province; consultations; and designing research projects and public outreach activities together. Comprehensive meeting minutes are kept and used to distill discussion points. The work of the group is disseminated through a variety of channels.

RESULTS

The public interest group includes 12 cancer patient and family member representatives, in addition to researchers. Discussions by the interest group identified key themes related to: (1) equity issues and regional disparity in provincial oncocare; (2) information needs; (3) need for patient empowerment and public understanding; and (4) family member and partner needs and experiences. To date, the group has co-designed a cancer research proposal and a public engagement/outreach activity. The group also provides consultations on cancer-related projects/public engagement activities and members act as patient partners in specific research and public engagement proposals. The group evolves over time, and increasingly advocates on behalf of cancer patients and families. Retention and satisfaction of the public partners with group activities have been high. The group's work and findings are disseminated to the Provincial Cancer Care Program, as well as to public and scientific stakeholders through local media, academic conferences and presentations, and a dedicated website.

CONCLUSION

Public Interest Group on Cancer Research represents a highly successful patient-researcher partnership in oncology. It designs meaningful and patient-oriented studies and outreach activities in cancer. It also elevates and widely supports cancer patient and family voice.

Comparison Between Familial Colorectal Cancer Type X and Lynch Syndrome: Molecular, Clinical, and Pathological Characteristics and Pedigrees

Objective

This study aimed to compare the molecular, clinical, and pathological characteristics and pedigrees of familial colorectal cancer type X (FCCTX) with those of Lynch syndrome (LS) to provide a theoretical basis for the management of FCCTX.

Methods

Overall, 46 cases of FCCTX and 47 LS probands and affected families were enrolled between June 2008 and September 2018 for this study. Multigene cancer panel tests that included 139 genes were performed for all patients, and variants in each group were described. The clinical, pathological, and pedigree characteristics were also compared between the two groups.

Results

In total, 42 variants were detected in 27 (58.7%) cases in the FCCTX group, with BRCA1, BRCA2, POLE, POLD1, ATR, and ATM being the most frequently mutated genes. The mean onset age of colorectal cancer (CRC) was significantly older in the FCCTX group than in the LS group (53.57 ± 12.88 years vs. 44.36 ± 11.26 years, t = −9.204, p < 0.001). The proportion of patients with rectal cancer was also higher in the FCCTX group than in the LS group [43.5% (20/46) vs. 10.6% (5/47), χ² = 12.823, p = 0.005]. Within a median follow-up time of 53.9 ± 37.0 months, the proportion of patients who developed metachronous CRC was significantly higher in the LS group than in the FCCTX group [34.0% (16/47) vs. 13.0% (6/46), χ² = 5.676, p = 0.017]. When comparing pedigrees, older age at cancer onset and rectal cancer clustering were observed in the FCCTX families. A higher prevalence in male patients was also observed in the FCCTX families.

Conclusion

FCCTX is an entity distinct from LS, but its genetic etiology remains unknown. A larger multigene panel would be recommended for determining the underlying pathogenic variants. Considering the pathology and moderate penetrance of the CRC link to FCCTX, less stringent surgical treatments and colonoscopy surveillance would be preferable. Rectum preference is a typical feature of FCCTX. Colonoscopy surveillance in FCCTX families could be less intensive, and more attention should be given to male members.

Broadening risk profile in familial colorectal cancer type X; increased risk for five cancer types in the national Danish cohort

Background

Familial colorectal cancer type X (FCCTX) is a phenotypically defined subset of hereditary colorectal cancer with unknown and potentially heterogeneous genetic aetiology. FCCTX has been characterized as a colorectal cancer-specific syndrome, which we herein challenge by estimating the risk for extra-colorectal cancer in the Danish FCCTX cohort.

Methods

Through the national hereditary non-polyposis colorectal cancer (HNPCC) register, 213 families fulfilling the Amsterdam I criteria and showing retained mismatch repair (MMR) function were identified. In here, sex and age-specific incidence rate ratios (IRR) were calculated for 30 extra-colorectal cancer types in comparison with the general Danish population.

Results

In total, 494 extra-colorectal cancers developed with significantly increased risks for cancers of the urinary tract, breast, stomach, pancreas, and eye tumours. The age groups at increased risks were 30–49 years for gastric cancer, 30–69 years for female breast cancer, 50–69 years for ocular melanoma and above age 70 for pancreatic cancer and urothelial cancer.

Conclusions

Danish FCCTX families show an increased risk of several extra-colorectal cancer types. This observation may indicate unidentified disease-predisposing genetic variants in this phenotypically defined subset of hereditary colorectal cancer and calls for awareness during genetic counselling and follow-up.

Prophylactic Surgery and Extended Oncologic Radicality in Gastric and Colorectal Hereditary Cancer Syndromes

Prophylactic surgery for high-penetrance hereditary gastric and colorectal cancer can be a primary prophylaxis of cancer and a secondary oncologic prevention. As early cancer is often detected in the resected organ, there has been no prophylaxis of cancer but cancer treatment. Extended oncological radicality with removal of the complete organ is a tertiary prevention as metachronous cancer is avoided. The indication for prophylactic surgery or extended oncological radicality is presented regarding hereditary and familial gastric and colorectal cancer. Hereditary diffuse type gastric cancer (E-cadherin mutation) and familial adenomatous polyposis coli (APC or MYH mutation) are well-accepted indications for prophylactic surgery with a variety of considerations regarding phenotype, genotype, associated diseases, age, timing, extent, and technique of surgery. Not so much prophylactic surgery as extended oncologic radicality can be considered in familial gastric and colorectal cancer as well as Lynch or hereditary nonpolyposis colorectal cancer syndrome (HNPCC). Clinical, molecular, and technical progress leads to less invasive and risk-adapted surgical and nonsurgical interventions, expanding the variety of individualized treatment options.

Impact of colonoscopic screening in Familial Colorectal Cancer Type X

Background

Hereditary Non‐Polyposis Colorectal cancer is caused by Lynch Syndrome (LS; an autosomal dominant condition) or by Familial Colorectal Cancer Type‐X (FCCTX; a condition of high family risk that fulfills Amsterdam criteria). The lifetime risk of developing colorectal cancer (CRC) in FCCTX family members is high and CRC occurs later than in LS.

Methods

To determine the impact of primary prevention colonoscopic screening in asymptomatic first‐degree relatives of incident CRC cases in 20 families with FCCTX, we compared cancer incidence and survival in 79 males and 83 females, assumed to be at 50% risk of inheriting a genetic CRC susceptibility factor, who entered screening to an unscreened control group from the families, matched for age at entry into screening and for sex.

Results

In males, median age at entry into screening was 44.8 years, median follow‐up 12.4 years, 12% developed CRC, and 46% died after 30 years of follow‐up. Compared to the unscreened group, relative risk of CRC was 0.27 (95% confidence intervals (CI) 0.10–0.71). In screened females, comparable results were 44.5 years at entry, 11.2 years of follow‐up, 7.1% developed CRC, and 7.2% died after 30 years of follow‐up. The relative risk of CRC compared to the unscreened group was 0.19 (95% CI 0.07–0.48).

Conclusion

Primary prevention screening colonoscopy in asymptomatic family members significantly decreased the risk of CRC in FCCTX.