Background: Endometrial squamous cell carcinoma is extremely rare, with only 56 cases reported in the literature.
Methods: Six cases of endometrial squamous cell carcinoma were found in a review of 1182 cases of uterine corpus cancer treated at the Massachusetts General Hospital from 1975 to 1993. Two additional cases were seen in pathological consultation. The clinicopathological features of these 8 cases and the 56 reported cases were analyzed.
Results: The average age of the patients was 67 years; almost all of them were postmenopausal. The most frequent presenting symptom was vaginal bleeding. Chronic pyometra and nulliparity were predisposing factors. The average duration of symptoms before diagnosis was 11.5 months. Total abdominal hysterectomy with bilateral salpingo-oophorectomy was the primary treatment in 58 patients. Eighty percent of the patients with Stage I tumors survived; the median follow-up time was 32 months. The survival rate for patients with Stage III tumors was only 20%, and all 6 patients with Stage IV disease died.
Conclusions: The preoperative diagnosis of endometrial squamous cell carcinoma may be difficult, since curettage specimens may show only highly differentiated squamous epithelium. The strong relationship between tumor stage and survival suggests that early diagnosis and treatment are imperative.