Hairy cell leukemia (HCL) is a rare disease of mature B-cell neoplasms. Its name comes from the hair-like strands surrounding the cytoplasm of the cells, which are observed on peripheral blood or bone marrow smears. Leukemic cells mainly involve the spleen, peripheral blood, and bone marrow. The classical immunophenotyping of HCL includes overexpression of the B-cell surface antigens such as CD19, CD20, and CD22 and co-expression of CD25, CD103, CD11c, and CD123. Other markers including CD5, CD10, and CD38 are usually negative, in which CD38 is considered a poor prognostic factor. Herein, we report a case of HCL with atypical morphology and abnormal expression of both CD38 and CD10.

Morphology and immunohistochemistry on node, tissue, and bone marrow biopsies are frequently used in lymphoma diagnosis to characterize the stage and subtype of diseases. Multicolor flow cytometry technology is a novel technique for the analysis of immunological markers to identify lymphoma on fresh tissue when immunohistochemical staining is ambiguous. We report a case of a patient diagnosed with diffuse large B-cell lymphoma by flow cytometry on a stomach tissue biopsy.

Background: Acute myeloid leukemia (AML) has the proliferation of poorly differentiated immature myeloid cells. New studies on immune markers also consider them as one of the factors that affect the prognosis or the patient's ability to respond to drugs. Our study was designed to determine the rate of remission and mortality, and the ability to respond to drugs in newly diagnosed AML patients with positive CD81. Methods: A total of 50 patients diagnosed with AML (excluding acute promyelocytic leukemia) underwent immunophenotyping analysis using flow cytometry. Following the initial diagnosis, the patients received induction therapy, followed by three cycles of consolidation therapy. The patients were then followed up for a period of six months. The treatment efficacy was assessed at two timepoints: on day 28 after the first chemotherapy course and on day 28 after the fourth chemotherapy course. Results: Out of the 50 newly diagnosed AML patients, 40 (80%) were found to be CD81 positive. This CD81-positive group had a high mortality rate after the first course of chemotherapy (17.5%) and after the fourth course of chemotherapy (52.5%), while no patients died in the CD81-negative group. The CD81-positive group had a worse drug response rate with 22.5% and 18.2% in CD81 positive group versus 30% and 40% in the CD81-negative group achieving complete remission after the first course and fourth course, respectively. Conclusions: The CD81 immunological marker was found to be highly prevalent among AML patients in Vietnam. Overexpression of CD81 in patients with AML is associated with an unfavorable prognosis, characterized by higher mortality rates and poorer treatment response.