Introduction. Induction chemotherapy (CT) for primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (CNS) is based on the use of methotrexate in high doses. An optimal consolidation strategy involves high-dose chemotherapy followed by autologous haematopoietic stem cell transplantation (auto-HSCT). The most effective conditioning regimen comprises a combination of chemotherapy agents including thiotepa.Aim. To present the authors’ experience of applying auto-HSCT/TBC in patients with primary DLBCL of the CNS.Methods. The prospective study CNS-2015 was carried out among 20 patients aged 20–52 years (median 42 years old) from 2015 to 2019. The male/female ratio came to 13/7. The somatic status of 17 (85 %) patients was 0–1 on the ECOG scale. Only 3 (15 %) patients showed the somatic status of 4 points. According to the criteria of the MSKCC prognostic system, 18 (90 %) and 2 (10 %) patients were assigned to the low-risk and medium-risk groups, respectively.Results. All patients included in the study received 3–5 cycles of chemotherapy with high doses of methotrexate, vincristine, procarbazine and rituximab (R-MPV), as well as underwent auto-HSCT following TBC-based conditioning regimen (thiotepa, busulfan, cyclophosphamide). Prior to auto-HSCT, 15 and 5 out of 20 patients having completed induction chemotherapy achieved complete remission and partial remission, respectively. Following auto-HSCT, complete remission was achieved in 5 patients with an initial partial response to treatment. All patients underwent temozolomide maintenance therapy for 2 years. With a median follow-up of 17 (1–46) months, 18 patients are alive and in remission. Two patients, who relapsed 4 and 5 months after auto-HSCT and achieved no response to the second line of chemotherapy and radiation therapy, died 24 and 26 months after auto-HSCT.Conclusion. R-MPV is an effective treatment for patients with primary DLBCL of CNS, which is not accompanied by severe toxicity. The use of high-dose chemotherapy with TBC allows a high remission rate to be achieved. The mortality associated with treatment in the group of patients included in the study came to 0 %.

Introduction. Primary mediastinal lymphoma (PML) is an aggressive lymphoid tumor treatment success of which is determined by induction therapy. To date, none of the standard chemotherapy regimens (CT) have demonstrated an advantage in efficacy. Intensive therapy programs are associated with high toxicity.Aim — to evaluate the efficacy and toxicity of two pilot prospective treatment protocols PML-16 and PML-19 as well as the possibility of using the analysis of freely circulating tumor DNA (ctDNA) to assess MRD in patients with PML.Materials and methods. From January 2016 to January 2022, 34 previously untreated PML patients were included in the study; average age — 32; stage > I — in 60 %; extramediastinal lesions — in 14.7 %; bulky disease — in 73.5 % of patients. Positron emission tomography combined with computed tomography (PET-CT) was performed; ctDNA was determined to assess the completeness of remission.Results. Eighteen patients received treatment according to the PML-16 protocol (6 courses of chemotherapy; 2 blocks of RmNHL-BFM-90 + 4 courses of R-EPOCH). After the end of therapy, all 18 patients achieved PET-negative remission. The next 16 patients received treatment according to the PML-19 protocol (4 courses of chemotherapy; 2 blocks of R-mNHL-BFM-90 + 2 courses of R-EPOCH) in combination with lenalidomide. After the end of therapy, 9 (56 %) patients achieved PET-negative remission; 7 (44 %) retained pathological activity (D4–5 points). After 3 and 6 months 15 (94 %) patients achieved normalization of metabolic activity. Considering the high frequency of false-positive results in patients with PML, a ctDNA study was performed to determine the depth of remission in 15 patients. After the end of therapy, all 15 patients had complete elimination of ctDNA. Of these, 5 (33 %) remained PET-positive at the end of treatment. During further observation, after 3–6 months, in 4 patients the level of metabolic activity decreased to physiological without the use of consolidating therapy. After the end of therapy, one patient suffered the new coronavirus infection, COVID-19. A month later, residual formation of SUVmax 14.2 remained in the mediastinum. The patient is currently under observation. With a median follow-up of 36 months (9 to 76 months) all 34 patients are in remission.Conclusion. The effectiveness of PML-16 made it possible to abandon the consolidation therapy and refuted the idea of the need for 6 courses of CT. The combination of programs based on the application of the principle of high-dose shortpulse induction of remission (R-mNHL-BFM-90) in combination with the prolonged administration of medium doses (R-EPOCH) was crucial in achieving a successful result. The inclusion of lenalidomide in the “PML-19” program made it possible to achieve complete remission in 100 % of cases after 4 courses. The possibility of using DNA analysis to assess MRD in patients with PML was shown.

Introduction. The use of invasive methods for diagnosing primary diffuse large B-cell lymphoma of the central nervous system (PDLBCL CNS) and primary vitreoretinal lymphoma (PVRL) is often associated with the development of severe neurological deficits and disability of patients. A promising direction in the diagnosis of PDLBCL CNS and PVRL is the use of non-invasive approaches based on molecular genetic methods for the determination of mutations in the MYD88 gene in the cerebrospinal fluid (CSF), vitreous fluid (VF) and free circulating tumor DNA (cfDNA) in blood serum.Aim: to present the potential of non-invasive diagnosis of PDLBCL CNS and PVRL.Main findings. The study included 6 patients (4 — PDLBCL CNS, 2 — PVRL). The average age was 64 (54–75) years. Despite increased cytosis in the CSF in all 4 patients with PDLBCL CNS, the tumor population was determined by flow cytometry in only half of the cases. According to a molecular genetic study, mutations in the MYD88 gene with an allelic load from 2.5% to 15% were detected in the genomic DNA of the CSF of all patients. In 2 patients with PVRL, mutations in the MYD88 gene were detected in VF with an allelic load of 4.2% and 6.6%, which was the only confirmation of the diagnosis. Currently, 5 patients have completed the treatment program and 1 is undergoing therapy. All 5 patients are in complete remission (CR) of the disease with follow-up periods from 1 to 8 months.

Introduction.Diffuse large B-cell lymphoma of postgerminal origin (ABC-DLBCL) and follicular lymphoma grade 3B (FL3B) are characterised by an aggressive course and resistance to chemotherapy (CT). Both diseases are characterised by the activation of genes of the post-terminal stage of B-cell differentiation and high expression of the MUM1 transcriptional protein. Lenalidomide in combination with R-CHOP improved the results of treatment in patients with ABC-DLBCL; however, about 40 % of them remain resistant to the therapy.Aim.The aim of the study was to evaluate the efficacy and toxicity of the R-mNHL-BFM-90 protocol with lenalidomide (R2-mNHL-BFM-90), as well as to analyse possible causes of CT resistance in patients with ABC-DLBCL and FL3B.Patients and methods.Over the period from October 2016 to December 2018, 8 patients with MUM1-positive DLBCL and FL3B were included in the research. All patients underwent a cytogenetic study of tumour samples. A mutational status of the TP53 gene was determined by Sanger sequencing.Results.Patients received combination chemotherapy according to the R2-mNHL-BFM-90 protocol with lenalidomide at a dose of 25 mg/day, from the 1st to the 10th day of each course. Autologous hematopoietic stem cell transplantation was performed as a consolidation in three patients. After the end of the chemotherapy, a complete remission of the disease was achieved in all patients. Relapse developed in 1 patient with a mutation in the TP53 gene. With a median follow-up period of 11 months (1–23), event-free survival was 87 %.Conclusions. The R2-mNHL-BFM-90 protocol has demonstrated a high efficacy and acceptable toxicity in patients with ABC-DLBCL and FL3B. The presence of a mutation in the TP53 gene is established to be an extremely unfavourable prognostic factor even provided intensive treatment protocols, thus requiring the development of alternative approaches to the management of such patients.

BACKGROUND. Up to now, neither the optimal treatment regimen for primary mediastinal large B-cell lymphoma (PMBCL), nor poor/favorable prognostic factors for risk stratification at the disease onset have been found. The prognosis of PMBCL is determined by the depth of metabolic response by the time of treatment completion, which underlies a response-adapted strategy. Besides, PMBCL is an aggressive tumor occurring more commonly in young women of reproductive age, which requires the development of treatment strategy during pregnancy. AIM. To assess the efficacy of the response-adapted strategy in PMBCL treatment based on the DA-EPOCH-R program in remission induction with drug dose escalation and without subsequent radiotherapy, if a complete metabolic response is reported by PET-CT. MATERIALS & METHODS. This prospective single-center clinical trial enrolled 154 patients in the period from November 2012 to March 2023. The median age of the patients was 34 years (range 19–68 years). There were 51 (33.1 %) men and 103 (66.9 %) women, 11 of whom were at various gestational ages of pregnancy. RESULTS. The response-adapted treatment was completed in all 154 patients. Overall response was 93.5 % (144/154), complete remission was 78.6 % (121/154), and partial remission was 14.9 % (23/154). Progression was reported in 6.5 % (10/154) of patients. With a follow-up of 60 months, the overall, disease-free, progression-free, and event-free survival rates were 93 %, 98 %, 92 %, and 76 %, respectively. The median was not reached. Prior to chemotherapy, 11 pregnant women aged 21–37 (median 29 years) had been assessed. By the time of PMBCL diagnosis, the gestational age of them varied from 9 to 37 weeks (median 26 weeks). Immunochemotherapy was administered to 9 women during pregnancy. At the gestational age of 27–38 weeks (median 34 weeks) delivery was reported in 10 patients who gave birth to 11 children. The children showed no malformations. All women with PMBCL diagnosed during pregnancy and all their children had been followed-up by the time of this publication. CONCLUSION. The response-adapted strategy of PMBCL treatment with the DA-EPOCH-R regimen and drug dose escalation showed a high immediate and long-term efficacy as well as tolerable toxicity, which provided ground for the decision against radiotherapy, if a complete metabolic response was reported by PET-CT. The results of this trial establish the main goal of treating aggressive lymphomas during pregnancy which is saving of two lives. Delivery of newborns without malformations despite immunochemotherapy justifies the use of the DA-EPOCH-R program at the gestational age > 12 weeks.

   Introduction. The follicular lymphoma (FL) is the most common indolent lymphatic tumor with high sensitivity to immunochemotherapy un most cases. Although overall survival (OS) is generally long, the disease is characterized by multiple relapses. High-dose chemotherapy (HDCT) with transplantation of autologous hematopoietic stem cells (auto-HSCT) is used for recurrent FL.   Aim: to evaluate the efficacy and safety of HDCT with aHSCT in the first line of FL therapy; identify risk factors for disease progression and refractoriness.   Material and methods. A prospective single-center study (conducted from May 2015 to January 2023) included 35 patients aged 18–65 years (median 43) with PL 1–3A grade t(14;18)+ with stages III–IV or stage II with bulky, having at least one criterion for the need to start therapy (according to GELF). Patients were treated according to the FL-2015 protocol: 4 R-CHOP, 2 R-DHAP and BeEAM with auto-HSCT. The primary endpoint was the rate of overall response (OR) and/or complete remission (CR) at the end of chemotherapy. Secondary end points were 3-year survival rates: OS, relapse-free survival (RFS), progression-free survival (PFS), and event-free survival (EFS). Minimal residual disease (MRD) in blood and/or bone marrow was assessed by PCR based on immunoglobulin heavy chain (IGH) gene rearrangements and/or BCL2::IGH rearrangements. Statistical analysis (by intent to treat) was performed on January 12, 2023.   Results. 86 % of patients had stage IV tumor and 79 % had 3–5 FLIPI factors. After the end of treatment, OR and PR were 90 % and 90 %, the incidence of POD24 was 3 %. After the end of induction (4 courses of R-CHOP), MRD-negativity was achieved in 77 % and 53 % of patients as determined by PCR-IGH and BCL2::IGH. After the full completion of the FL-2015 protocol, MRD was not detected in 96 % of patients (according to PCR-IGH). Three-year overall survival, disease-free survival, progression-free survival and event-free survival were respectively: 90 %, 90 %, 95 % and 85 % (with the same standarderror of 9 %) at a median follow-up (by inverse Kaplan-Meier estimate) of 19 months (range: from 1 to 91 months) There were no deaths due to early toxicity within 100 days of auto-HSCT. Prognostically unfavorable independent statistically significant (р < 0.01; Wald test; hazard ratio > 1) predictors of progression and refractoriness according to the results of multivariate analysis using the Fine-Grey competing risk model (р = 0.052 for the model) were: bone marrow disease, ECOG high risk, patient age > 50 years, stage 4 disease, elevated serum lactate dehydrogenase and B-symptoms.   Conclusion. The use of HDCT with auto-HSCT in the first line in patients with FL is highly effective and can significantly reduce the incidence of POD24 and early mortality from the tumor. The study is ongoing.