Familial aggregation of carcinoma of the endometrium

Review of immunohistochemical typing of endometrial carcinoma at the Lagos University Teaching Hospital

BACKGROUND

Categorization of endometrial carcinomas as type I and II provides useful insights into their different risk factors, pathogenesis and biologic behaviours.

AIM

To determine the immunohistochemical classifications of endometrial carcinomas in Nigerian women.

DESIGN

A retrospective review of histopathologic slides of cases of endometrial carcinomas seen at the Lagos University Teaching Hospital (LUTH) over a 5-year period. The slides were reviewed, and the diagnoses made according to the WHO nomenclature. The classification of endometrial carcinomas into Type I and II was made by immunohistochemistry using antibodies to ER, PR, p53 and Ki-67.

RESULTS

Eight cases of endometrial adenocarcinoma were reported accounting for 53.3% of all endometrial malignancies. Of these, only 1 case showed the classic type I immunophenotype while type II staining pattern was seen in 4 cases. The remaining 3 cases had equivocal immunophenotypes: one was p53+ but showed ER+, PR+ and high Ki-67 index; the second was p53-, ER+, PR+ but had a high Ki-67 expression; while the last was p53-, but ER-, PR- and had high Ki-67 expression.

CONCLUSION

Endometrial carcinomas in Nigerian women are more likely to be type II carcinomas. A reasonable proportion of the cases were equivocal thus requiring further categorization with molecular studies.

New therapies for advanced, recurrent, and metastatic endometrial cancers

Endometrial cancer is the most common gynecologic malignancy in the United States, accounting for 6% of cancers in women. In 2017, an estimated 61,380 women were diagnosed with endometrial cancer, and approximately 11,000 died from this disease. From 1987 to 2008, there was a 50% increase in the incidence of endometrial cancer, with an approximate 300% increase in the number of associated deaths. Although there are many chemotherapeutic and targeted therapy agents approved for ovarian, fallopian tube and primary peritoneal cancers, since the 1971 approval of megestrol acetate for the palliative treatment of advanced endometrial cancer, only pembrolizumab has been Food and Drug Administration (FDA)-approved for high microsatellite instability (MSI-H) or mismatch repair deficient (dMMR) endometrial cancer; this highlights the need for new therapies to treat advanced, recurrent, metastatic endometrial cancer. In this review, we discuss current and emerging treatment options for endometrial cancer, including chemotherapy, targeted therapy, and immunotherapy. The National Cancer Institute (NCI) and others are now focusing their efforts on the design of scientifically rational targeted therapy and immunotherapy trials for specific molecular phenotypes of endometrial cancer. This is essential for the advancement of cancer care for women, which is threatened by a severe enrollment decline of approximately 80% for gynecologic oncology clinical trials.

Molecular analysis of familial endometrial carcinoma: a manifestation of hereditary nonpolyposis colorectal cancer or a separate syndrome?

PURPOSE

Familial clustering of endometrial carcinoma (EC) may occur as part of hereditary nonpolyposis colorectal cancer (HNPCC), a multiorgan cancer syndrome with mismatch repair (MMR) deficiency. Clustering of EC alone, termed as familial site-specific EC, may constitute a separate entity. Because its genetic basis is unknown, our purpose was to characterize such families molecularly.

MATERIALS AND METHODS

Twenty-three families with site-specific EC were identified among 519 consecutive patients diagnosed with EC during 1986 to 1997. Tumor tissues were examined for MMR protein expression by immunohistochemical (IHC) analysis, and MMR genes pinpointed by IHC changes were screened for germline mutations by exon-by-exon sequencing, multiplex ligation-dependent probe amplification, and direct tests for mutations common in the population.

RESULTS

Among 33 ECs from 23 families, MLH1 protein was lost in seven tumors (21%), MSH2 together with MSH6 was lost in four tumors (12%), and MSH6 alone was lost in five tumors (15%). A truncating germline mutation in MSH6 (3261insC) was identified in one family and a likely pathogenic missense mutation in MSH2 (D603N) was identified in another family. Among the original 519 patients, nine (all with colon cancer in the family) were diagnosed with HNPCC at the outset-six with MLH1 and three with MSH2 mutations.

CONCLUSION

Our study gives a minimum overall frequency of 2.1% (11 of 519) for germline MMR defects ascertained through EC in the index patients. The fact that only two of 23 families with site-specific EC (8.7%) had germline mutations in MMR genes suggests another as yet unknown etiology in most families with site-specific EC.

Clinicopathologic and familial characteristics of endometrial carcinoma with multiple primary carcinomas in relation to the loss of protein expression of MSH2 and MLH1

BACKGROUND

The frequency of synchronous or metachronous multiple primary carcinomas in patients with endometrial carcinoma has been reported to be between 10% and 23% and is highest among all gynecologic carcinomas. However, clinical characteristics and underlying genetic abnormalities in endometrial carcinoma with multiple primary carcinomas has not been well clarified. Endometrial carcinoma is the most commonly associated extracolonic malignancy in hereditary nonpolyposis colorectal carcinoma in which germ line mutations in DNA mismatch repair genes, particularly in MSH2 and MLH1, are known to cause this syndrome. The purpose of the current study was to investigate clinicopathologic and familial characteristics including MSH2, MLH1, and p53 expression in endometrial carcinoma with multiple primary carcinomas, by comparing them to endometrial carcinoma without other primary malignancies.

METHODS

Patients were divided into two groups: 30 patients with synchronous or metachronous multiple primary carcinomas other than endometrial carcinoma and 116 patients with endometrial carcinoma without other primary malignancies. Clinicopathologic characteristics, family history of cancer, and immunohistochemical protein expression of MSH2, MLH1, and p53 expression were investigated in both groups, and 15 endometria from benign disease were used for normal controls in immunohistochemistry.

RESULTS

The frequency of high risk clinicopathologic factors of endometrial carcinoma and 5-year survival rates and the frequency of p53 overexpression were not statistically different between the two groups. However, the loss of MSH2 and/or MLH1 expression was significant in endometrial carcinoma with multiple primary carcinomas, when compared with endometrial carcinoma alone (22 of 30 vs. 31 of 116). In cases with multiple primary carcinomas, particularly those diagnosed before the patient was 55 years of age or those in which the patient had a family history of cancer, the frequency of this loss was especially high (11 of 13 and 10 of 11, respectively).

CONCLUSIONS

The clinical or biologic nature of endometrial carcinoma with multiple primary carcinomas seems to be similar to endometrial carcinoma alone. A high incidence of defective MSH2 and MLH1 protein in endometrial carcinoma with multiple primary carcinomas, however, suggests that abnormalities in the function of MSH2 and MLH1 may play an important role in tumorigenesis for patients with endometrial carcinoma with multiple primary carcinomas and their families.

Atypical clustering of gynecologic malignancies: A family study including molecular analysis of candidate genes

OBJECTIVE

We set out to determine whether hereditary nonpolyposis colorectal cancer (HNPCC) was responsible for cancer susceptibility in a family with gynecologic malignancies in three consecutive generations.

METHODS

A detailed family history study, including review of medical records, was undertaken. Tumor DNAs from affected family members were evaluated for microsatellite instability (MSI). Linkage between cancer susceptibility and the candidate DNA mismatch repair genes MLH1, MSH2, MSH3, and MSH6 (GTBP) was investigated. MLH1 and MSH2 protein expression was evaluated by immunohistochemistry and MSH2 was investigated for mutation.

RESULTS

Four gynecologic malignancies in the core family were confirmed. MSI was seen in six of seven cancers studied. The only MSI-negative tumor was an ovarian cancer from the proband's maternal grandmother, which arose at the age of 92. Haplotype analysis using chromosome 2p markers implicated the MSH2 gene in this family's cancer susceptibility. MSH2 protein expression was absent in an MSI-positive colon cancer from an affected family member.

CONCLUSIONS

The inability to exclude linkage of MSH2 with the disease susceptibility, the presence of the MSI phenotype in cancers from family members sharing the same region of chromosome 2p, and the lack of immunodetectable MSH2 point to MSH2-associated HNPCC as a cause for this family's cancer susceptibility. Continued efforts to increase awareness of the heritability of endometrial cancer should improve our understanding of the disease, with resultant improved surveillance strategies, recommendations for surgical and chemoprophylaxis, and identification of patients at risk for malignancy as a result of HNPCC.