Dedifferentiated endometrioid adenocarcinoma of the uterus: a clinicopathologic study of a case.

Dedifferentiation confers more aggressive malignant behaviour than would be otherwise shown by the original tumor if present alone. This phenomenon has been described in several tumors, both mesenchymal and epithelial. Dedifferentiated endometrioid carcinoma either ovarian or endometrial is the latest addition to this family of tumors. Only 2 papers have appeared in the literature so far on the topic of dedifferentiated endometrioid carcinoma, both from the same institution. We report herein a case of endometrial dedifferentiated endometrioid carcinoma in a 45-year old lady with ovarian metastasis from the undifferentiated component. The primary endometrial tumor showed an undifferentiated component in an otherwise low grade endometrioid carcinoma. The undifferentiated component of these tumors can be misdiagnosed as the solid component of FIGO grade 3 in a pure endometrioid carcinoma. The recognition of an undifferentiated component in an otherwise low grade endometrioid carcinoma is very important, since dedifferentiated endometrioid adenocarcinoma has a worse prognosis when compared with FIGO grade 3 endometrioid carcinoma.

Modulation of CD20 antigen expression after rituximab treatment: a retrospective study in patients with chronic lymphocytic leukemia.

BACKGROUND: CD20 antigen down-modulation by anti-CD20 rituximab treatment is a well-recognized phenomenon in patients with non-Hodgkin's lymphoma. However, few data are currently available on this topic in other lymphoproliferative disorders, in particular in chronic lymphocytic leukemia (CLL). OBJECTIVE: The aim of this study was to establish how many patients with CLL show a disappearance of CD20 antigen after salvage treatment with rituximab and its possible clinical significance. METHODS: We sequentially analyzed CD20 expression by flow cytometry in patients treated with rituximab in combination with other agents for relapsed/resistant disease. RESULTS: Eleven white patients with CLL (6 females, 5 males; median age, 71.6 years [range, 60-84 years]) were included in the study. Three of the 11 patients were not positive for CD20 due to complete response at baseline. Four of the remaining 8 patients (50%) lacked CD20 antigen on neoplastic cells after monoclonal antibody treatment. Two of them developed Richter's syndrome and died within 4 months. The phenomenon was transient in the other 2 patients, who were alive after a follow-up of 25 and 26 months, respectively, with CD20-positive recurrent disease. CONCLUSIONS: In this study, CD20 antigen disappearance in patients with CLL treated with rituximab-containing salvage regimens occurred in 4 of 8 (50%) tested patients, half of whom developed Richter's syndrome. [Note: Since the initial writing and submission, a third patient developed Richter's syndrome.] In 2 patients (50%), CD20 returned at progression.