Morphological basics of ovarian tumor histogenesis

Researches about the origin of epithelial ovarian tumors (EOT) tell about its conception. In particular, the origin of cells from the secondary mullerian system. Also, in the article we examine a new hypothesis that the EOT originates in the epithelium of the fallopian tube (FT) – their contradictoriness and new conception of “precursor escape” which tries to explain the phenomenon of injuries absence of FT by high-grade serous ovarian carcinoma. Carcinogenesis from the FT represents great opportunities for reassessment of clinical data. Also, the article represents the role of stem cells of the surface epithelium of ovaries and FT in EOT carcinogenesis.

A divergent pseudoglandular configuration of cutaneous plasmacytoma in dogs

Cutaneous and mucocutaneous plasmacytoma (PCT) is a common neoplasm of dogs. Tumors can be single or multiple and occur predominantly in the oral cavity, lip, ears, digits, and trunk. Although these tumors typically offer no diagnostic challenge for the pathologist, subsets of PCTs with atypical morphologic configurations may make differentiation from other neoplasms difficult. We describe 6 cases of canine cutaneous and mucocutaneous PCT with pseudoglandular arrangement of neoplastic cells. The mean age of affected dogs was 11.3 y, and multiple breeds and sites were affected. Histologically, neoplastic cells were arranged in sheets, packets, and pseudoglandular structures containing central accumulations of blood or eosinophilic material admixed with neoplastic cells and hemosiderin-laden macrophages. Given the presence of pseudoglandular structures resembling neoplastic acini, epithelial neoplasia was occasionally included in the differential diagnosis. Neoplastic cells were strongly immunopositive for multiple myeloma oncogene 1 ( MUM-1) and immunonegative for pancytokeratin AE1/AE3. Canine cutaneous and mucocutaneous PCTs with pseudoglandular morphology may resemble epithelial neoplasia and raise questions about tumor histogenesis.

The role of tumor histogenesis, FDG-PET, and short-course EPOCH with dose-dense rituximab (SC-EPOCH-RR) in HIV-associated diffuse large B-cell lymphoma

This is a phase 2 study to assess the role of tumor histogenesis (subtype), fluorodeoxyglucose positron emission tomography (FDG-PET), and short-course etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin with dose-dense rituximab (SC-EPOCH-RR) in newly diagnosed HIV-associated CD20+ diffuse large B-cell lymphoma. Patients received a minimum of 3 and a maximum of 6 cycles with 1 cycle beyond stable radiographic and FDG-PET scans. Overall, 79% of patients received 3 cycles. Combination antiretroviral therapy was suspended before and resumed after therapy. Thirty-three enrolled patients had a median age of 42 years (range, 9-61 years), and 76% had a high-intermediate or high age-adjusted international prognostic index. At 5 years median follow-up, progression-free and overall survival were 84% and 68%, respectively. There were no treatment-related deaths or new opportunistic infections during treatment, and patients had sustained CD4 cell count recovery and HIV viral control after treatment. FDG-PET after 2 cycles had an excellent negative but poor positive predictive value. Tumor histogenesis was the only characteristic associated with lymphoma-specific outcome with 95% of germinal center B-cell (GCB) versus 44% of non-GCB diffuse large B-cell lymphoma (DLBCL) progression-free at 5 years. SC-EPOCH-RR is highly effective and less immunosuppressive with shorter duration therapy compared with standard strategies. However, new therapeutic advances are needed for non-GCB DLBCL, which remains the important cause of lymphoma-specific death. This trial was registered at www.clinicaltrials.gov as NCT000019253.