[Successful treatment of a patient with two hematologic tumors: double-hit lymphoma and acute myelomonoblastic leukemia].

Double-hit (DH) lymphoma, an extremely aggressive variant of B-cell lymphoma, is accompanied by chromosomal abnormalities leading to the activation of a few oncogenes, one of which is the c-MYC gene in conjunction with BCL2 or BCL6 gene rearrangements. There are most common cases of MYC/8q24 and BCL2/18q21 gene rearrangements (MYC/BCL-2 DH lymphoma). The tumor is characterized by an aggressive clinical course and a poor response to chemotherapy (CT). The median survival in patients with DH lymphomas varies from 4.5 to 18 months. Such patients are generally resistant to CHOP-21 and R-CHOP-21 therapy regimens. For the treatment of patients with DH lymphoma, the Hematology Research Center, Ministry of Health of the Russian Federation, chose an original BL-M-04 polychemotherapy (PCT) protocol in combination with rituximab, followed by autologous stem cell transplantation (allo-SCT). The paper describes the experience in successfully treating a patient with two hematologic tumors: 1) MYC/BCL-2 DH lymphoma with high-dose PCT cycles, followed by allo-SCT, and 2) a metachronously developed second tumor (acute myelomonoblastic leukemia (AMML)) with CT cycles, followed by auto-SCT. The incidence of tumors induced by the previous high-dose CT for aggressive lymphomas for 10 years is 0.7 to 10%. As a rule, the development of secondary AMML is preceded by a history of myelodysplastic syndrome (MDS); characteristic chromosomal abnormalities (deletions of the long arm of chromosomes 5 and 7) are detectable. In this case, the follow-up was 3 months before the development of AMML, during this period the patient was not found to have laboratory signs of MDS (anemia, thrombocytopenia) or chromosomal abnormalities associated with secondary MDS/AML. The presence of a leukemic stem cell is associated with the occurrence and development of hemoblastosis; that of the similar cell populations that may cause B-cell lymphomas remains uncertain. The described case may have defect in a hematopoietic stem cell that gives rise to both germs of hematopoiesis, as well as complete donor chimerism of bone marrow hematopoiesis, which gives hope to long-term remission in both DH lymphoma and AMML.

[The specific features of renal lesion in Burkitt's lymphoma].

AIM: To analyze the causes of renal lesion in patients with Burkitt's lymphoma (BL) and to develop optimal treatment policy. MATERIALS AND METHODS: The data of examination and treatment were analyzed in 20 patients with BL (14 men and 6 women aged 15 to 57 years (median age 24 years)) who had been followed up for renal lesion at the Hematology Research Center (HRC) in 2003 to 2011. When admitted to hospital, all the patients were found to have ureteric compression, renal parenchymal tumor infiltration, massive tumor cytolysis syndrome (MTCS). Polychemotherapy (PCT) was performed in accordance with the original intensive BL-M-04 protocol. The extent of the process was estimated according to the classification developed by S.B.Murphy: L3 variant B of acute lymphoblastic leukemia in 10 cases; Stage IV in 2; Stage III in 8. Acute renal failure (ARF) was identified in 13 patients. A control group comprised 36 patients with BL without ARF who had been followed up at the HRC in 2003 to 2011 and included into the BL-M-04 protocol. The ratio of patients with bone marrow lesion was 7:13 and 9:36 in the BL + ARF and BL-ARF groups, respectively. RESULTS: Decreased urine specific gravity and proteinuria (0.4 to 1.3 g/l) were the first manifestations of renal lesion and were seen in approximately 50% of all cases both on admission to hospital and in the first stages of PCT (10 and 9, 8 and 7 of the 20 cases, respectively). Microhematuria more commonly developed after initiation of PCT (7 and 3 of the 20 cases, respectively). ARF was diagnosed in 13 patients (24% of the 55 BL patients followed up at HRC in 2003 to 2011). One female patient developed ARF after the start of PCT. Twelve patients developed this condition at the onset of disease; in 4 patients, ARF existing prior to PCT began progressing after drug administration. The etiology of ARF was generally mixed. At the onset of disease, MTCS (n = 6) and specific renal parenchymal infiltration (n=6) were more common causes of ARF. Postrenal anuria was present in 2 cases. ARF after PCT initiation resulted from the toxic effects of methotrexate and MTCS (3 and 4 cases, respectively). ARF regressed in the early periods: in the prophase (n = 4) and during or the first PCT block A (n = 9). The BL patients with ARF, as compared to those without the latter, showed a statistically significant earlier onset of myelotoxic agranulocytosis (MTA): on day 3 of an intercourse interval (95 CI from 0 to 3 days) versus its day 5 (95% CI from 2 to 5 days) and a statistically significant longer duration of MTA--12 days (95% CI from 7 to 16 days) versus 7 days (95% Cl from 3 to 10 days); they were observed to have more severe mucositis. Despite the longer intercourse interval, 10 patients with ARF achieved remission; 4 patients died from therapy-refractory sepsis and 1 patient from thrombocytopenia. In the patients with ARF, mortality rates were significantly higher than in those without ARF (33% versus 10%; p = 0.04). CONCLUSION: Although there is a high risk of worsening renal dysfunction, PCT is a necessary condition for ARF resolution in BL.