Endometrial serous carcinoma (ESC) is an aggressive neoplasm wherein the recent studies have shown that it arises from its putative precursor namely the serous endometrial intraepithelial carcinoma (SEIC). SEIC usually arises in inactive/ atrophic endometrium but surprisingly is frequently associated endometrial polyps (EPs). The aim of this study was to assess the incidence of SEIC with or without invasion, its clinical behaviour and association with endometrial polyp.

After Institutional review board approval, a total of 205 samples (belonging to 120 patients); diagnosed as ESC from January 2009 to December 2015 were retrieved and reviewed for presence of in situ carcinoma and also for associated endometrial polyp.

The mean age at diagnosis was 62.40 years with postmenopausal bleeding being the most common presenting symptom. The incidence of SEIC with or without invasive tumor was 40% (48/120). Of these 48 cases; 25 cases were associated with in-situ carcinoma arising in the EPs which amounted to 52% of the total cases. The overall three year survival and disease free survival in SEIC with or without invasion were 1.9% and 0.25%, indicating the aggressive nature of the disease.

SEIC is a difficult histopathological diagnosis and one should carefully look for these lesion, especially in the EPs which are frequently associated with them. Extensive sampling of the EP will be helpful to pick up in-situ carcinoma arising in EP. SEIC is an aggressive disease on its own with a propensity to develop distant metastasis even in the absence of myometrial invasion and hence should be treated with optimum surgical staging and if indicated aggressive adjuvant treatment protocols.