Main aspects and result ’s treatment of primary mediastinal b-cell large lymphoma

The best choice of treatment of patients with primary mediastinal B-cell large lymphoma (PMBCL) is very important, taking into account the results of combined positron emission and computed tomography with 18F-FDG (PET/CT) at various stages of the disease clinical progression.

The aim: Increase the treatment success in patients with PMBCL by the rational use of the drug and radiation therapy.

Materials and methods: We analyzed therapy results of 101 patients with PMBCL who received either only
immunopolychemotherapy (34 patients, R-CHOP or R-DA-EPOCH) or combined treatment with radiation (67 patients.
PET/CT was performed before treatment, after immunopolychemotherapy and combination therapy.

Results: Complete remissions were achieved in 94 (93,1%) patients, including those who received combined treatment in 65 of 67 (97,0%) patients; and with drug therapy only – in 29 of 34 (85,3%) patients (p<0,02). Primary disease progression with subsequent unfavorable outcome was more frequent in the only drug therapy group than in the chemoradiotherapy group (14,7% and 3,0%, respectively, p<0,02). There were no relapses after combined treatment, but in the drug-only group 1 patient had shown a relapse in the mediastinum (p=0,04) after 34 months. The frequency of low efficiency of the first line of immunopolychemotherapy was the same after R-CHOP (20,0%) and R-DA-EPOCH (30,4%), p>0,1. After the first line of immunopolychemotherapy, the absence of metabolic activity (DC1-3) was observed in 48 (76,2%) of 63 examined patients. They are all alive and in remission. 4 from 15 (26,7%) patients with PET-positive results of the study (DC4-5) after immunopolychemotherapy had an unfavorable progress of disease which is significantly worse compared to those of the PET-negative group (100%, p<0,01). 5-year overall, progression-free and relapse-free survival of patients in the whole group was 91,6%, 89,9% and 95,5%; with only drug therapy and combined treatment was: total – 79,6% and 97,0% (p=0,005); nonprogressive – 77,5% and 97.0% (p=0,005); relapse-free – 92,6% and 100% (p>0,1).
Conclusion: Efficiency of first-line immunopolychemotherapy schemes was comparable. Long-term results were better with immunochaemoradiotherapy; the presence of PET-negative data after the first line of immunopolychemotherapy is a favourable prognostic sign. Radiation therapy executed in proper time helps to reduce the systemic cytostatic stress.