Clinical Characteristics and Prognosis of Gastric Cancer Patients with BRCA 1/2 Germline Mutations: Report of Ten Cases and a Literature Review

Background

The prognosis of gastric cancer (GC) is poor with a median overall survival (OS) of less than 12 months in advanced-stage disease. The search for distinct genetic subgroups of GC patients and predictive biomarkers is ongoing. While BRCA1 or BRCA2 germline mutations (gBRCAm) have potential therapeutic implications in ovarian, breast and pancreatic cancers, their significance in GC patients has not been established.

Patients and Methods

A retrospective multi-center data analysis of GC patients with gBRCAm was conducted, detailing the clinical characteristics and disease course in this unique subset of patients.

Results

Ten GC patients with gBRCAm were identified, six of them with metastatic disease. The median OS of all ten GC patients was 47.5 (13–192) months. Median OS for patients diagnosed with operable disease was 55.5 (13–192) months and of the patients with metastatic disease (calculated from metastatic disease diagnosis) 32 (15–52) months with an exceptional 1-, 2- and 3-year survival rate of 100%, 83.3% and 50%, respectively.

Conclusion

These preliminary data suggest that gBRCAm in GC patients are associated with a favorable prognosis. Furthermore, gBRCAm might be a predictive biomarker to DNA-damaging agents response in GC patients, similarly to its established role in other malignancies. Further research is needed to confirm our findings.

The yield of full BRCA1/2 genotyping in Israeli high-risk breast/ovarian cancer patients who do not carry the predominant mutations

PURPOSE

BRCA1 and BRCA2 genotyping results have clinical implications for cancer risk assessment and targeted therapy. Current practice in Israel is to genotype for the predominant BRCA1/2 mutations first, followed by full gene analysis in eligible mutation-negative individuals. This work assessed the rate of non-predominant mutations in BRCA1/2 in ethnically diverse high-risk cases.

METHODS

Breast and/or ovarian cancer patients who tested negative for the predominant BRCA1/2 mutations were referred for comprehensive BRCA1/2 genotyping if calculated risk for carrying a BRCA mutation was ≥ 10%.

RESULTS

Of 1258 eligible patients, 41 (3.3%) carried one of 38 mutations: 3% of Ashkenazi Jews and 3.4% of mixed ethnicities. Detection rate was < 5% among patients diagnosed with cancer younger than 40 or with bilateral breast cancer, and was 5.5% of ovarian cancer patients. Three of the carriers (7.3%) carried gene rearrangements. Three mutations were reported in more than one case.

CONCLUSIONS

The overall yield of comprehensive BRCA1/2 testing in ethnically diverse high-risk Israeli individuals is 3.3%. This is lower than expected by probability models. A slightly higher rate of BRCA1/2 carriers was seen among ovarian cancer cases. These data should guide BRCA1/2 optimal testing strategy in Israel.

Constitutional Mismatch Repair Deficiency in Israel: High Proportion of Founder Mutations in MMR Genes and Consanguinity

BACKGROUND

Heterozygous germline mutations in any of the mismatch repair (MMR) genes, MLH1, MSH2, MSH6, and PMS2, cause Lynch syndrome (LS), an autosomal dominant cancer predisposition syndrome conferring a high risk of colorectal, endometrial, and other cancers in adulthood. Offspring of couples where both spouses have LS have a 1:4 risk of inheriting biallelic MMR gene mutations. These cause constitutional MMR deficiency (CMMRD) syndrome, a severe recessively inherited cancer syndrome with a broad tumor spectrum including mainly hematological malignancies, brain tumors, and colon cancer in childhood and adolescence. Many CMMRD children also present with café au lait spots and axillary freckling mimicking neurofibromatosis type 1.

PROCEDURE

We describe our experience in seven CMMRD families demonstrating the role and importance of founder mutations and consanguinity on its prevalence. Clinical presentations included brain tumors, colon cancer, lymphoma, and small bowel cancer.

RESULTS

In children from two nonconsanguineous Ashkenazi Jewish (AJ) families, the common Ashkenazi founder mutations were detected; these were homozygous in one family and compound heterozygous in the other. In four consanguineous families of various ancestries, different homozygous mutations were identified. In a nonconsanguineous Caucasus/AJ family, lack of PMS2 was demonstrated in tumor and normal tissues; however, mutations were not identified.

CONCLUSIONS

CMMRD is rare, but, especially in areas where founder mutations for LS and consanguinity are common, pediatricians should be aware of it since they are the first to encounter these children. Early diagnosis will enable tailored cancer surveillance in the entire family and a discussion regarding prenatal genetic diagnosis.

The gastrointestinal manifestation of constitutional mismatch repair deficiency syndrome: from a single adenoma to polyposis-like phenotype and early onset cancer

Data on the clinical presentation of constitutional mismatch repair deficiency syndrome (CMMRD) is accumulating. However, as the extraintestinal manifestations are often fatal and occur at early age, data on the systematic evaluation of the gastrointestinal tract is scarce. Here we describe 11 subjects with verified biallelic carriage and who underwent colonoscopy, upper endoscopy and small bowel evaluation. Five subjects were symptomatic and in six subjects the findings were screen detected. Two subjects had colorectal cancer and few adenomatous polyps (19, 20 years), three subjects had polyposis-like phenotype (13, 14, 16 years), four subjects had few adenomatous polyps (8, 12-14 years) and two subjects had no polyps (both at age 6). Of the three subjects in the polyposis-like group, two subjects had already developed high-grade dysplasia or cancer and one subject had atypical juvenile polyps suggesting juvenile polyposis. Three out of the five subjects that underwent repeated exams had significant findings during short interval. The gastrointestinal manifestations of CMMRD are highly dependent upon age of examination and highly variable. The polyps may also resemble juvenile polyposis. Intensive surveillance according to current guidelines is mandatory.

A familial gastrointestinal cancer clinic: organization, aims and activities, 2004-2007

BACKGROUND

Dedicated, organ-specific screening clinics have been shown to significantly reduce cancer morbidity and mortality.

OBJECTIVES

To establish a dedicated clinic for Clalit Health Service patients at high risk for hereditary gastrointestinal cancer and to provide them with clinical and genetic counseling, diagnostic screening and follow-up.

RESULTS

During the 3 years of the clinic's activity, 634 high risk families, including 3804 at-risk relatives, were evaluated. The most common conditions were hereditary colorectal syndromes, Lynch syndrome (n=259), undefined young-onset or familial colorectal cancer (n=214), familial adenomatous polyposis (n=55), and others (n=106). They entered follow-up protocols and 52 underwent surgical procedures.

CONCLUSIONS

Consistent public and professional education is needed to increase awareness of hereditary colorectal cancer and the possibility of family screening, early diagnosis and therapy. The public health services--i.e., the four health management organizations--should provide genetic testing for these patients who, at present, are required to pay for almost all of these available but costly tests. Dedicated colorectal surgical units are needed to provide the specialized therapeutic procedures needed by patients with familial colorectal cancer. Our future plans include adding psychosocial support for these at-risk patients and their families as well as preventive lifestyle and dietary intervention.

Elevated human chorionic gonadotropin levels in pregnancies with sex chromosome abnormalities

Numerous reports have dealt with the usefulness of the maternal serum alpha-fetoprotein marker (MsAFP) and human chorionic gonadotropin (MshCG) levels in the detection of Down syndrome (DS) and other autosomal trisomies. Only few reports have discussed the possible association of elevated levels of MshCG and sex chromosome aneuploidy. We wish to report on 3 cases in which this association was found.