Ovarian cancer linked to Lynch syndrome typically presents as early-onset, non-serous epithelial tumors.

OBJECTIVE

Heredity is a major cause of ovarian cancer and during recent years the contribution from germline mismatch repair (MMR) gene mutations linked to Lynch syndrome has gradually been recognized.

METHODS

We characterized clinical features, tumor morphology and mismatch repair defects in all ovarian cancers identified in Swedish and Danish Lynch syndrome families.

RESULTS

In total, 63 epithelial ovarian cancers developed at mean 48 (range 30-79) years of age with 47% being early stage (FIGO stage I). Histologically, endometrioid (35%) and clear cell (17%) tumors were overrepresented. The underlying MMR gene mutations in these families affected MSH2 in 49%, MSH6 in 33% and MLH1 in 17%. Immunohistochemical loss of the corresponding MMR protein was demonstrated in 33/36 (92%) tumors analyzed.

CONCLUSION

The combined data from our cohorts demonstrate that ovarian cancer associated with Lynch syndrome typically presents at young age as early-stage, non-serous tumors, which implicates that a family history of colorectal and endometrial cancer should be specifically considered in such cases.