In a real-world analysis, researchers across France and Belgium evaluated results with first-line treatment of patients with primary mediastinal B-cell lymphoma (PMBL) and found that chemoimmunotherapy approaches may be associated with positive outcomes. Results of this study were reported in the journal Blood Advances.
In this retrospective analysis conducted across 25 centers, patients with PMBL had been given 1 of 3 first-line treatment approaches. These included rituximab plus doxorubicin, cyclophosphamide, vindesine, bleomycin, and prednisone (R-ACVBP), and rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) given for either 14 days (R-CHOP14) or 21 days (R-CHOP21). The primary endpoint of the analysis was progression-free survival (PFS).
R-ACVBP was given to 180 patients in this study, while 76 patients received R-CHOP14, and 57 patients received R-CHOP21. Rates of consolidation using autologous stem cell transplantation were 25.6% in the R-ACVBP group, 31.6% in the R-CHOP14 group, and 1.8% in the R-CHOP21 group. A small number of patients (5.4%) were given mediastinal radiotherapy.
With a median follow-up of 44 months, the 3-year PFS rate with R-ACVBP was 89.4% (95% CI, 84.8%-94.2%), for R-CHOP14 it was 89.4% (95% CI, 82.7%-96.6%), and for R-CHOP21 it was 74.7% (95% CI, 64%-87.1%). PFS was significantly different across treatment groups (P =.018), as was 3-year overall survival (OS; P =.0036). The R-ACVBP (92.4%) and R-CHOP14 (100%) groups showed higher OS rates than seen with R-CHOP21 (87.5%). After treatment, the complete metabolic response rates were 86.3% with R-ACVBP, 86.8% with R-CHOP14, and 76.6% with R-CHOP21 (P =.23).
Univariate analysis suggested that use of R-CHOP21 (P =.012), presence of B symptoms (P =.034), and a total metabolic tumor volume (TMTV) of ≥360 cm3 (P =.037) were associated with lower PFS, but multivariable analysis did not reveal significant predictors of PFS in this study. However, multivariable analysis showed a TMTV of ≥360 cm3 to be associated with overall survival (P =.007).
Regarding safety, R-ACVBP showed a higher rate of febrile neutropenia (24.4%) than was seen with R-CHOP14 (5.3%) or R-CHOP21 (5.3%). Mucositis was also more common with R-ACVBP (22.8%) than with R-CHOP14 (3.9%) or R-CHOP21 (1.8%).
“In this study, patients who received R-CHOP14 or R-ACVBP had excellent outcomes with limited acute toxicity,” the researchers concluded in their report. They noted that these results suggest positive outcomes can occur for patients with PMBL using first-line chemoimmunotherapy without a requirement for radiation therapy.
Disclosures: Some authors have declared affiliations with or received grant support from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
Camus V, Rossi C, Sesques P, et al. Outcomes after first-line immunochemotherapy for primary mediastinal B-cell lymphoma: a LYSA study. Blood Adv. 2021;5(19):3862-3872. doi:10.1182/bloodadvances.2021004778.