Analysis Indicates Continued Risk of Relapse Independent of Treatment Modality in Limited-Stage DLBCL


Key Points

  • Long-term follow-up in the SWOG S8736 trial showed no difference in progression-free or overall survival in patients with limited-stage DLBCL receiving CHOP3RT vs CHOP8.
  • Treatment with rituximab plus CHOP3RT in the SWOG S0014 study was also associated with continued relapse risk.

In an analysis of data from SWOG studies reported in the Journal of Clinical Oncology, Stephens et al found as continued risk of relapse among patients with limited-stage diffuse large B-cell lymphoma (DLBCL) irrespective of whether they received CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) with or without radiotherapy or rituximab (Rituxan) plus CHOP with radiotherapy.

Long-Term Follow-up

In the SWOG S8736 trial, 3 cycles of CHOP plus radiotherapy (CHOP3RT) improved 5-year progression-free and overall survival vs 8 cycles of CHOP (CHOP8) in patients with limited- stage DLBCL; however, subsequent analysis showed an overlap of the progression-free survival curves.

In the current analysis including 150 patients receiving CHOP8 and 158 receiving CHOP3RT in the trial, with a median follow-up of 17.7 years, median progression-free survival was 12.0 vs 11.1 years (P = .73), and median overall survival was 13.0 vs 13.7 years (P = .38). Progression-free survival was 69% vs 76% at 5 years, 55% vs 55% at 10 years, and 41% vs 40% at 15 years.

Rituximab and CHOP3RT

In an analysis of 56 patients with limited-stage DLBCL receiving rituximab and CHOP3RT in the SWOG S0014 study, with a median follow-up of 12 years, progression-free survival was 77% at 5 years and 58% at 10 years. Overall survival was 82% at 5 years and 67% at 10 years, with a persistent pattern of relapse being observed.

The investigators concluded: “Although 5-year [progression-free survival] and [overall survival] were improved after early analysis in patients with limited-stage DLBCL receiving CHOP3RT versus CHOP8, extended survival data showed similar [progression-free survival] and [overall survival], with continuous treatment failure. The addition of rituximab (S0014) to combined-modality therapy did not mitigate the continued relapse risk, underscoring the value of prolonged clinical trial patient observation and possible unique biology of limited-stage DLBCL.”

The study was supported by the National Institutes of Health (NIH)/National Cancer Institute (NCI)/National Clinical Trials Network grants and NIH/NCI Community Oncology Research Program grants.

Sonali M. Smith, MD, of the University of Chicago, is the corresponding author of the Journal of Clinical Oncology article.

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