Classification of AIDS-related lymphoma cases between 1987 and 2012 in Japan based on the WHO classification of lymphomas, fourth edition.

The introduction of combined antiretroviral therapy (ART) has reduced the mortality of patients with human immunodeficiency virus-1 infection worldwide. However, malignant lymphoma is a severe and frequent complication seen in patients with acquired immunodeficiency syndrome (AIDS). The diagnostic criteria for some categories of AIDS-related lymphoma were revised in the World Health Organization International Classification of Lymphoma, fourth edition. The purpose of this study was to assess the clinicopathological characteristics of Japanese patients with AIDS-related lymphoma according to the revised classification. In this retrospective study, 207 AIDS-related lymphoma cases diagnosed between 1987 and 2012 in Japan were subjected to histological subtyping and clinicopathological analyses. Diffuse large B-cell lymphoma (DLBCL) was the predominant histological subtype throughout the study period (n = 104, 50%). Among the DLBCL cases, 24% were of the germinal center (GC) type and 76% were of the non-GC type. Non-GC-type cases showed a significantly lower 1-year survival rate (43%) than the GC-type cases (82%). Cases of Burkitt lymphoma (n = 57, 28%), plasmablastic lymphoma (n = 16, 8%), primary effusion lymphoma (n = 9, 4%), Hodgkin lymphoma (n = 8, 4%), and large B-cell lymphoma arising in Kaposi sarcoma-associated herpesvirus-associated multicentric Castleman disease (n = 2, 1%) were also observed. Hodgkin lymphoma was more common in patients receiving ART (11.1%) than in ART-naïve patients (1.4%). Statistical analyses identified CD10 negativity, BCL-6 negativity, Epstein-Barr virus positivity, and Kaposi sarcoma-associated herpesvirus positivity as risk factors for poor prognosis. This information will help in the early diagnosis of lymphoma in patients with AIDS.

HER-2/neu cytoplasmic staining is correlated with neuroendocrine differentiation in breast carcinoma.

HER2 oncoprotein plays an essential role in breast cancer growth and differentiation. Determination of HER2 status contributes not only to predicting survival but also to selecting the patients for anti-HER2 therapy. HER2 protein expressed in human cancer cells often contains variant forms as well as the full-length wild-type form. In the present study, we investigated the subcellular localization of HER2 protein in 1053 primary breast cancer tissues. HER2 protein was stained by various immunohistochemical methods and studied by immunoelectron microscopy to confirm the intracellular localization. Thirty-four of 1053 specimens showed cytoplasmic staining of the intracellular domain of HER2 protein by the HercepTest and CB-11. In contrast, no immunoreactivity to the antibodies against the extracellular domain was observed. None of the 34 specimens showed amplification of the HER2 protein by fluorescence in situ hybridization. Subsequently, we studied the association of the cytoplasmic expression of HER2 with neuroendocrine differentiation. Interestingly, all 34 specimens had some positive signals of neuroendocrine markers such as synaptophysin, chromogranin A, neuron-specific enolase, and CD56. Although the result is preliminary, it warrants further study on the role of the cytoplasmic variant form of HER2 in breast cancer growth, particularly in the aspect of neuroendocrine differentiation.