Title : Dedifferentiated mucinous ovarian carcinoma: A case report and literature review
Abstract:
Introduction. Dedifferentiated mucinous carcinoma of the ovary is a rare, highly aggressive and molecularly distinct ovarian malignancy, characterised by frequent inactivation of core SWI/SNF complex and typically a low response rate to platinum-based standard care for ovarian cancer.
Presentation of case: We here report a case of dedifferentiated mucinous carcinoma in a 50-year-old patient, who morphologically showed spectrum of well, moderate and undifferentiated carcinoma and a distinct immunohistochemical profile, as documented by application of wide range immunohistochemistry. It also underwent detailed molecular testing in two independent institutions. Results show alterations in numerous genes such as BRCA2, SMARCA4, ARID1A, TP53, STK11, EP300, KRAS and MTAP. Tumour was also MMR deficient. Moreover, distinct expression patterns in B-Catenin and E-Cadherin are noted in different areas of tumour, which warrant further studies, but raise the possibility of post-transcriptional alterations in Wnt signalling pathway.
Discussion: Morphological and immunohistochemical characteristics of tumour, differential diagnoses and review of literature have been discussed, as well as the utility of molecular profiling for precision cancer therapies.
Conclusion: Dedifferentiated mucinous carcinoma of the ovary is an aggressive neoplasm, characterised by alterations in core SWI/SNF complex. Detailed molecular profiling of these tumours can optimise the selection of molecular-matched therapies.
Audience Take Away:
- The audience will learn about morphological, immunohistochemical and distinct molecular characteristics of this rare but highly aggressive ovarian malignancy. Main differential diagnoses will be discussed, and review of literature will be presented together with the up-to date molecular findings which may help to optimize therapeutic protocols.
- Learning about tumour characteristics may help in its early recognition and diagnosis and tempestive request of ancillary analysis for precision therapy.
- Recognising the type of tumour and its aggressive course and resistance to standard therapy will direct the audience toward molecular profiling to address optimization of therapy protocol relative to specific molecular alterations found in tumour.
- These tumours show inactivation of core SWI/SNF complex, involved in chromatin remodelling and cell differentiation. This molecular aberration is shared with several other gynaecological malignancies and understanding the exact mechanism or carcinogenesis may be of interest to other research group and applicable to other malignancies which share alterations within the same complex.
- Detailed molecular profiling leads to selection of the most suitable therapeutic regime for each patient, based on specific molecular profile of disease.
