Prognostic significance of serous and clear cell adenocarcinoma in surgically staged endometrial carcinoma

BACKGROUND: The serous adenocarcinoma (SA) and clear cell adenocarcinoma (CCA) of endometrium have been shown to be associated with high relapse rate and poor survival. It is not clear whether prognostic significance of these specific cell types of tumor is independent of retroperitoneal lymph node metastasis and other histopathologic prognostic factors in endometrial carcinoma. METHODS: We examined 240 consecutive patients with clinical stage I to stage III endometrial carcinoma who were treated prospectively with radical surgery and/or platinum-based chemotherapy. Surgery included extended hysterectomy, bilateral salpingo-oophorectomy, and systematic pelvic and paraaortic lymph node dissection. Prognostic significance of various histopathologic factors was determined by Cox regression analysis. RESULTS: SA/CCA were more frequently associated with deep myometrial invasion, high nuclear grade (G3), lymph-vascular space invasion (LVSI), and pelvic lymph node metastasis when compared to endometrioid adenocarcinoma (EMA). Of 216 clinically staged stage I or II disease, seven of 12 cases of SA/CCA had extrauterine disease. This incidence was much higher than that for EMA (46/204) (p<0.01). A multivariate Cox regression analysis revealed that cell type, grade, LVSI, and paraaortic node metastasis (PANM) were independent prognosticators. CONCLUSIONS: Prognosis of patients with endometrial carcinoma depends on cell type, grade, LVSI, and PANM. Poor prognosis for patients with SA/CCA is independent of lymph node metastasis and other histopathologic prognostic factors. The SA/CCA should be strictly discriminated from EMA.