[Therapy for Burkitt's lymphoma according to the BL-M-04 protocol: 12-year experience].

AIM: To evaluate the efficiency and toxicity of the intensive Burkitt's lymphoma (BL) therapy protocol BL-M-04. SUBJECTS AND METHODS: A total of 70 patients diagnosed with BL, including 45 men and 25 women whose age was 15 to 62 years (median age 31 years), were followed up in 2003 to 2014. Stage I (according to S. Murphy) was diagnosed in 4 (5.7%) patients; II in 9 (12.9%), III in 25 (35.7%), IV in 11 (15.7%), and Burkitt's leukemia in 21 (30%). There were tumor involvements of the bone marrow and central nervous system in 23 (32.9%) and 15 (21.4%) patients, respectively. B symptoms were detected in 56 (80%) patients; enhanced lactate dehydrogenase (LDH) activity was found in 50 (78.1%) out of 64 patients; moreover, in 34 (56.2%) out of 64 patients, LDH activity was more than twice as high as the reference values. The median LDH activity was 2398 (238-20,300) U/I. Acute renal failure at disease onset was identified in 17 (24.2%) patients; chemotherapy was initiated in 8 patients during renal replacement therapy. The treatment was performed using the BL-M-04±R protocol (4 successive blocks of A-C-A-C±R). Six blocks of A-C-A-C-A-C with rituximab has been carried out in patients with bone marrow involvement since 2011. RESULTS: Sixty-two (89%) patients achieved complete remission. At this time, 6 patients died from therapy complications during remission induction; 2 patients were observed to have disease progression; 3 developed disease recurrence (2 patients had early recurrence; 1 patient developed recurrence 2 years after treatment). Five-year overall survival (OS) was 85%; 5-year relapse-free survival (RFS) was 95%. The Cox multivariate regression analysis revealed that Burkitt's leukemia and bone marrow involvement were independent factors that influenced OS and RFS. The poor somatic status (3-4 ECOC scores versus 0-2 scores) proved to be statistically significant for OS rather than RFS. CONCLUSION: Despite the optimistic results obtained by our study group, there is a need to further improve BL treatment protocols and to elaborate novel approaches to therapy particularly for older patients and patients with Burkitt's leukemia.

[Diagnosis and treatment in patients with B-cell lymphoma unclassified that is intermediate between diffuse large B-cell lymphoma and Burkitt's lymphoma]. / Diagnostika i lechenie bol'nykh V-kletochnoi limfomoi neklassifitsiruemoi, zanimayushchei promezhutochnoe polozhenie mezhdu diffuznoi V-krupnokletochnoi limfomoi i limfomoi Berkitta.

AIM: To characterize a group of patients with B-cell lymphoma (BCLU) unclassified that is intermediate between diffuse large B-cell lymphoma and Burkitt's lymphoma, to identify poor prognostic factors, and to evaluate therapeutic efficiency in patients with BCLU. SUBJECTS AND METHODS: Twenty-five patients with BCLU were examined. Double-hit lymphoma (DHL) was diagnosed in 8 (32%) patients. According to the Ann-Arbor classification of lymphoma, its stages II, III, and IV were diagnosed in 3 (12%), 2 (8%), and 20 (80%) patients, respectively. MYC rearrangement was observed in 11 (48%) out of 23 patients: single-hit lymphoma in 3 patients and DHL in 8 (BCL2+/MYC+ in 6 cases and BCL6+/MYC+ in 2). The expression of с-MYC (cut off ≥40%) was revealed in 17 (74%) out of 23 patients; that of BCL2 (cut off ≥50%) was detected in 14 (58%) out of 24 patients; coexpression of both proteins was seen in 12 (52%) out of 23 patients. The DHL group showed a correlation between the rearrangement of the BCL2+/MYC+ genes and the expression of MYC and BCL2 proteins in 5 out of 6 patients. Taking into account the heterogeneity of the entire patient group, DHL and non-DHL subgroups were considered separately. Both subgroups were comparable by clinical characteristics. BCLU patients younger than 60 years of age received treatment according to the LB-M-04 ± rituximab; those aged 60 or older had CHOP-like regimens ± rituximab. Autologous stem cell transplantation (auto-SCT) was performed in 5 patients belonging to a high-risk group. RESULTS: The 3-year overall survival (OS) was 62% and the 3-year event-free survival (EFS) was 51%. The 3-year OS was lower for the DHL group than that for the non-DHL group (43 and 75%, respectively). CONCLUSION: In the DHL group, both OS and EFS are significantly lower (the risk of poor outcome, including death, is higher) than those in the non-DHL group. It is conceivable that intensified chemotherapy with auto-SCT increases treatment results in patients with BCLU; however, a larger number of observations are needed to obtain valid data.