Familial colorectal cancer: Patient assessment, surveillance and surgical management

Oncology Informatics for Lynch Syndrome Research and Care: A Literature Review

PURPOSE

This study aims to review and evaluate available informatics platforms for research and management purposes of Lynch syndrome (LS) to identify gaps and needs for future development.

METHODS

LS informatics tools were identified through literature search in four publication databases (1 and Scopus). First, the LS and functional elements of every informatics tools for LS were introduced. Then, current existing LS informatics tools were reviewed and explained.

RESULTS

A detailed review of implemented studies shows that many types of informatics platforms are available for LS management (ie, prediction model, clinical decision support system, database website, and other tools for research and management purposes of LS). Moreover, several dimensions of existing LS informatics tools were discussed and features and positive findings were reported.

CONCLUSION

Reviewing the literature reveals that several LS informatics tools were focused on gene-specific estimate, cancer risk prediction, identifying/screening patients, supporting personalized care of individuals with LS, and storing mismatch repair mutations information. Nevertheless, these platforms do not fully cover the care and research purposes. For instance, future developments of LS tools require more attention to dynamic knowledgebase, extra-colonic lynch–related cancers on the basis of precision medicine, variants of unknown significance, and support from diagnosis to surveillance for patient follow-up. Insights and recommendations provided in this study could help researchers and developers to meet the existing challenges in future developments.

Current guidelines in the surgical management of hereditary colorectal cancers

Incidence of colorectal cancer (CRC) is on rise. While approximately 70% of all CRC cases are sporadic in nature, 20%-25% have familial aggregation and only < 5% is hereditary in origin. Identification of individuals with hereditary predilection for CRC is critical, as it has an impact on their overall surgical management including surgical timing, approach & technique and determines the role of prophylactic surgery and outcome. This review highlights the concept of hereditary CRC, provides insight into its molecular basis, possibility of its application into clinical practice and emphasizes the current treatment strategies with surgical management, based on the available international guidelines.

Polyposis and Oncologic Outcomes in Young-onset Sporadic Colorectal Cancer

Aim

The present study aimed to investigate the effect of the presence of polyposis in sporadic early-onset colorectal cancer (EOCRC) on clinicopathological and oncological outcomes.

Methods

The retrospective study included patients with sporadic colorectal cancer aged 16 to 50 years who underwent curative resection at the general surgery clinics in two healthcare centers between 2013 and 2019. Patients were divided into two groups: polyposis and nonpolyposis. Clinicopathological characteristics and oncological outcomes were compared between the two groups.

Results

A total of 127 patients were included, of whom 60.6% were men. There were 25 (19.68%) patients in the polyposis group and 102 (80.31%) patients in the nonpolyposis group. Seventy-one (69.6%) of the nonpolyposis group and 23 (92.0%) of the polyposis group had adenocarcinoma histological types. The total number of patients with mucinous tumor and signet ring cell carcinoma in the nonpolyposis and polyposis groups was 31 (30.4%) and 2 (8.0%), respectively (p = 0.042). Five-year overall survival (OS) was 60 and 72% in the nonpolyposis and polyposis groups, respectively, and no significant difference was found (p = 0.332). In univariate analysis, American Joint Committee on Cancer (AJCC) tumor stage (pT) ≥3–4, lymph node positivity, presence of mucinous tumor and signet ring cell carcinoma, lymphovascular invasion, and advanced tumor-lymph nodesmetastasis (TNM) stage (III–IV) were found to be significant negative prognostic factors for OS, whereas none of these parameters were found to be prognostic factors in multivariate analysis. The presence of polyposis was not a significant factor on both univariate and multivariate analyses.

Conclusion

Although the sporadic EOCRC cases developing on the basis of polyposis can have slightly better oncological outcomes, these outcomes are mostly similar to those of cases with nonpolyposis.

How to cite this article

Aday U, Kafadar MT, Oğuz A, et al. Polyposis and Oncologic Outcomes in Young-onset Sporadic Colorectal Cancer. Euroasian J Hepato-Gastroenterol 2021;11(1):6–10.

The genetic factors associated with Wnt signaling pathway in colorectal cancer

Colorectal cancer (CRC) is a common cancer with poor prognosis and high mortality. There is growing information about the factors involved in the pathogenesis of CRC. However, the knowledge of the predisposing factors is limited. The development of CRC is strongly associated with the Wingless/Integrated (Wnt) signaling pathway. This pathway comprises several major target proteins, including LRP5/6, GSK3β, adenomatous polyposis coli (APC), axis inhibition protein (Axin), and β-catenin. Genetic variations in these components of the Wnt signaling pathway may lead to the activation of β-catenin, potentially increasing the proliferation of colorectal cells. Because of the potentially important role of the Wnt signaling pathway in CRC, we aimed to review the involvement of different mutations in the main downstream proteins of this pathway, including LRP5/6, APC, GSK3β, Axin, and β-catenin. Determination of the genetic risk factors involved in the progression of CRC may lead to novel approaches for the early diagnosis of CRC and the identification of potential therapeutic targets in the treatment of CRC.

Estimating the age at onset distribution of the asymptomatic stage of a genetic disease based on pedigree data

Information on the age at onset distribution of the asymptomatic stage of a disease can be of paramount importance in early detection and timely management of that disease. However, accurately estimating this distribution is challenging, because the asymptomatic stage is difficult to recognize for the patient and is often detected as an incidental finding or in case of recommended screening; the age at onset is often interval-censored. In this paper, we propose a method for the estimation of the age at onset distribution of the asymptomatic stage of a genetic disease based on ascertained pedigree data that take into account the way the data are ascertained to overcome selection bias. Simulation studies show that the estimates seem to be asymptotically unbiased. Our work is motivated by the analysis of data on facioscapulohumeral muscular dystrophy, a genetic muscle disorder. In our application, carriers of the genetic causal variant are identified through genetic screening of the relatives of symptomatic carriers and their disease status is determined by a medical examination. The estimates reveal an early age at onset of the asymptomatic stage of facioscapulohumeral muscular dystrophy.

Increased serological, cancer-associated protein biomarker levels at diagnosis of large bowel adenoma: Risk of subsequent primary malignancy?

BACKGROUND

Blood-based, cancer-associated biomarkers may detect subjects at risk of having neoplastic diseases. The aim of the present study was to evaluate whether elevated serological protein biomarker levels may identify adenoma patients, who are at increased risk of being diagnosed with subsequent primary malignancy.

METHODS

Levels of CEA, CA19-9, TIMP-1 and YKL-40 were determined in blood samples collected prior to diagnostic bowel endoscopy due to symptoms of colorectal neoplasia. Follow-up time was ten years, and identified adenoma patients, who were diagnosed with subsequent primary intra- or extra-colonic malignant diseases. The biomarker levels were also determined in 400 subjects, who underwent diagnostic colonoscopy, had clean colorectum and were without apparent co-morbidity; these levels were used as reference levels. In the present study, biomarkers were interpreted as elevated when levels were above the reference intervals adjusting for age and gender. The 1-year and 5-years cumulative incidences were calculated.

RESULTS

Primary malignancies were identified in 175 (19%) of the 923 subjects diagnosed with adenomas at the primary bowel endoscopy. In detail, 20 of the 175 subjects were diagnosed with colorectal cancer (CRC) and 155 subjects with extra-colonic cancers. Thirty patients were diagnosed with malignancy within the first year. Three groups were established: 0: no elevated biomarkers; 1: 1 of the 4 biomarkers elevated; and 2: ≥2 biomarkers elevated. The cumulative 5-years incidence of malignancy was: 0: 6.9%; 1: 11.8%; and 2: 17.5% (p = .0009).

CONCLUSION

Elevated blood-based, cancer-associated protein biomarker levels in subjects diagnosed with adenomas at large bowel endoscopy identifies subjects at increased risk of being diagnosed with subsequent primary malignancy.

Familial risk for lung cancer

Lung cancer, which has a low survival rate, is a leading cause of cancer-associated mortality worldwide. Smoking and air pollution are the major causes of lung cancer; however, numerous studies have demonstrated that genetic factors also contribute to the development of lung cancer. A family history of lung cancer increases the risk for the disease in both smokers and never-smokers. This review focuses on familial lung cancer, in particular on the familial aggregation of lung cancer. The development of familial lung cancer involves shared environmental and genetic factors among family members. Familial lung cancer represents a good model for investigating the association between environmental and genetic factors, as well as for identifying susceptibility genes for lung cancer. In addition, studies on familial lung cancer may help to elucidate the etiology and mechanism of lung cancer, and may identify novel biomarkers for early detection and diagnosis, targeted therapy and improved prevention strategies. This review presents the aetiology and molecular biology of lung cancer and then systematically introduces and discusses several aspects of familial lung cancer, including the characteristics of familial lung cancer, population-based studies on familial lung cancer and the genetics of familial lung cancer.

Familial adenomatous polyposis in China

Familial adenomatous polyposis (FAP) is an autosomal dominant disease with a poor prognosis, and has been studied by clinicians and geneticists in China for the past three decades. It is estimated that FAP has an incidence of between 1 in 8,000 and 1 in 10,000 individuals, and accounts for 0.94% of colorectal cancer cases in China. Recent advances in the understanding of FAP suggest that the genotype of the patient may allow for early diagnosis and surveillance, and guide surgical and chemopreventive management. However, the genetic mechanisms of FAP vary between different countries. FAP in China has its own characteristics, and this may be due to ethnic and geographical genetic variation. In the present review the clinical manifestations and genetics of FAP in China are discussed, as well as the surgical strategies, chemotherapeutics and traditional Chinese medicines used in its treatment. Increased insight into the genetic and clinical features of FAP in the Chinese population may aid in the prevention and management of the disorder.