Update on rare epithelial ovarian cancers: based on the Rare Ovarian Tumors Young Investigator Conference

Abstract

There has been significant progress in the understanding of the pathology and molecular biology of rare ovarian cancers, which has helped both diagnosis and treatment. This paper provides an update on recent advances in the knowledge and treatment of rare ovarian cancers and identifies gaps that need to be addressed by further clinical research. The topics covered include: low-grade serous, mucinous, and clear cell carcinomas of the ovary. Given the molecular heterogeneity and the histopathological rarity of these ovarian cancers, the importance of designing adequately powered trials or finding statistically innovative ways to approach the treatment of these rare tumors has been emphasized. This paper is based on the Rare Ovarian Tumors Conference for Young Investigators which was presented in Tokyo 2015 prior to the 5th Ovarian Cancer Consensus Conference of the Gynecologic Cancer InterGroup (GCIG).

Epithelial ovarian cancer: Evolution of management in the era of precision medicine

“…Mucinous ovarian cancer is a rare subtype representing 2.4% of EOCs . Some may arise from borderline tumors . Microscopically, mucinous ovarian cancer is heterogeneous and often is composed of benign, borderline, noninvasive, and invasive components that coexist within the tumor microenvironment .…”

“…51 Some may arise from borderline tumors. 52 Microscopically, mucinous ovarian cancer is heterogeneous and often is composed of benign, borderline, noninvasive, and invasive components that coexist within the tumor microenvironment. 19 Mucinous ovarian cancer is characterized by the presence of multiocular cysts filled with an opaque, mucoid substance and larger solid regions and papillae that project into the cysts.…”

Outcomes of non-high grade serous carcinoma after neoadjuvant chemotherapy for advanced-stage ovarian cancer: a Korean gynecologic oncology group study (OV 1708)

“…The MEK inhibitor (MILO) trial is a phase III study investigating the efficacy of MEK 162, a MEK inhibitor, compared to physician choice chemotherapy for recurrent or persistent LGSC. A phase III trial (Gynecologic Oncology Group (GOG)-241) compared the efficacy of chemotherapy regimens for mucinous carcinoma: capecitabine-oxaliplatin versus carboplatin-paclitaxel and with or without bevacizumab in mucinous subtype tumors was closed early for slow accrual, and neither of regimen clearly improved PFS or OS [30, 31]. Furthermore, in mucinous carcinoma, trastuzumab (Herceptin) may be effective for patients with HER2 overexpression [32].…”

Urachal Mucinous Cystic Tumor of Low Malignant Potential with Concurrent Sigmoid Colon Adenocarcinoma

“…Most urachal neoplasms are epithelial (glandular) neoplasms (see classification in Table 1), typically with an intestinal phenotype [1–11]. The spectrum of cystic urachal mucinous neoplasms (described in Table 2), including mucinous cystadenoma, mucinous cystic tumor of low malignant potential, and mucinous cystadenocarcinoma [12], is similar to the morphologic spectrum of appendiceal [13] and ovarian [12, 14] intestinal-type mucinous neoplasms. Consequently, the absence of a known primary glandular neoplasm at another anatomical site has been put forward as a criterion for pathologic diagnosis of a urachal mucinous neoplasm [12, 15].…”