Características citogenéticas y detección de anormalidades de alto riesgo en mieloma múltiple / High risk cytogenetic abnormalities in patients with multiple myeloma

Background: Cytogenetic abnormalities observed in the bone marrow of patients with multiple myeloma (MM) are an important prognostic factor for risk stratification. Aim: To investigate karyotype characteristics and frequency of the high-risk cytogenetic abnormalities t(4;14), t(14;16) and del(17p) in Chilean patients with MM. Material and Methods: We studied 30 patients with MM by conventional cytogenetics (CC) and fluorescent in situ hybridization of plasma cells selected using cytoplasmic immunoglobulin staining (cIg-FISH). Results: Overall, the two techniques in combination allowed us to identify clonal genetic abnormalities in 47% of patients. The t(4;14) abnormality was observed in 19% of patients, del(17p) was observed in 10% of patients, and t(14;16) was not detected. Conclusions: Our results showed frequencies of high-risk abnormalities similar to those reported abroad. Cytogenetic studies should be performed routinely for all MM patients at the moment of diagnosis.

Hipercalcemia, peak monoclonal y leucemización como presentación de un linfoma de células B de alto grado, con reordenamiento de MYC, BCL-2 y BCL-6 (Triple Hit). Caso clínico / Hypercalcemia, monoclonal peak and leukemic presentation of a High-grade B-cell lymphoma with MYC, BCL-2 and BCL-6 translocations (triple hit). Report of one case

High-grade B-cell lymphomas with rearrangement of MYC, BCL-2 and/or BCL-6 were introduced by the update of the WHO classification of lymphoid neoplasms. They usually present unique morphological and molecular characteristics, with an aggressive clinical outcome and worse prognosis. We report a 48 year-old female patient presenting with B symptoms and enlarged lymph nodes. Blood count showed pancytopenia and peripheral blood smears showed large lymphoid cells, some with nuclei and vacuoles. LDH was 3524 g/L and serum calcium was 11.5 mg/dL. Flow cytometry immunophenotyping showed pathological mature B lymphocytes. Protein electrophoresis showed a slight monoclonal peak. The biopsy disclosed a triple expressor diffuse large B-cell lymphoma, arising from germinal center. FISH was positive for MYC, BCL-2 and BCL-6 (triple hit) with a clonal evolution. Conventional cytogenetics showed a complex karyotype. Chemotherapy was started with R-CHOP (Rituximab/cyclophosphamide/doxorubicin/vincristine/prednisone). She developed impaired consciousness; the brain CT scan showed a large brain mass. The patient died within 3 weeks.