Investigation of the clinical features of lower uterine segment carcinoma: association with advanced stage disease and indication of poorer prognosis

Purpose: We retrospectively analyzed the differential clinical features and prognosis of endometrial carcinomas arising from the lower uterus, which are reported to have a poorer prognosis than those arising from the upper uterus. Methods: 246 patients with endometrial carcinoma who underwent surgery were entered as subjects. Results: Twenty-three were classified as having lower uterine segment carcinomas (LUSC); the remaining 223 were upper uterine segment carcinomas (UUSC). LUSC cases were associated with a more advanced FIGO stage than UUSC (p < 0.001). Deep myometrial invasion and lymph node metastasis were more common in LUSC than in UUSC (p = 0.006 and p < 0.001, respectively). LUSC cases demonstrated significantly shorter overall survival (OS) and progression-free survival (PFS) than UUSC (p = 0.02 and p < 0.001, respectively). Multivariate cox proportional hazards analysis demonstrated that the hazard ratio for LUSC was 1.769 for OS and 3.479 for PFS. For endometrial carcinoma survival, FIGO stage and histological type were extracted as independent variables. Conclusions: LUSC is a high-risk indicator for poorer prognosis for endometrial carcinoma because it is associated with more advanced stage disease, deep myometrial invasion and lymph node metastasis, and indicates a significantly worsened PFS probability. Our analysis concludes that LUSC is FIGO stage-dependent and an important factor for OS.