Carcinoma of the endometrium in Norway: a histopathological and prognostic survey of a total population

In a histopathological review of a total population, 1974 cases of endometrial carcinoma were found from 1970 to 1977. Of these 1566 (79.3%) were adenocarcinomas of the endometrioid type, 181 (9.2%) adenoacanthomas, 97 (4.9%) clear cell carcinomas, 74 (3.7%) adenosquamous carcinomas, 31 (1.6%) undifferentiated carcinomas, 22 (1.1%) serous papillary carcinomas and 3 (0.1%) squamous cell carcinomas. Thirty percent of the tumors were well differentiated, 44% moderately and 25.9% poorly differentiated. The mean age at diagnosis was 62.0 years (range 32–93 years). Age was clearly related to histologic type, grade and extent of myometrial infiltration. Crude 5- and 10-year survival rates for the entire group were 73.1 and 61%. For the different subtypes of endometrial carcinoma the 5- and 10-year crude survival rates were as follows: adenoacanthoma 91.2 and 79.6%, adenocarcinoma of the endometrioid type 74.1 and 62.2%, adenosquamous carcinoma 64.9 and 52.7%, undifferentiated carcinoma 58 and 48%, clear cell carcinoma 42.3 and 30.9% and serous papillary carcinoma 27 and 14%. All three patients with squamous cell carcinoma died within a year. The 5- and 10-year survival rates were 87.8 and 79.7% for grade 1 tumors, 76.6 and 62.1% for grade 2, and 60.1 and 48.6% for grade 3. The extent of myometrial infiltration was a string predictor of prognosis. The 5- and 10-year survival rates of patients with intramucosal tumors and tumors infiltrating the inner half of the myometrium were, respectively 89.6 and 82.5%, and 84.7 and 72.7%. Only 48.3 and 29.3% of the patients with tumors reaching the serosa survived, respectively 5 and 10 years. Patients without demonstrable vessel invasion had a significantly better prognosis than those with vessel invasion with a survival rate of 83.5 and 61.1% at 5- and 10-years, compared with 64.5 and 53.8%, respectively. Age at the time of diagnosis was an important prognostic factor for crude survival. Surgico-pathological staging was significantly better than clinical staging in predicting prognosis only in advanced stages.