Event-free survival at 24 months (EFS24) is predictive of survival in patients with peripheral T-cell lymphomas (PTCLs), according to new findings published in the Journal of Clinical Oncology.
Patients who were event free 2 years after diagnosis had a more favorable outcome, compared with those who relapsed within that time period. Some patients who remained event free for 24 months were potentially cured; conversely, events within 2 years were associated with an early death in almost all of those patients.
“Thus, EFS24 is a dichotomous end point that allows individualized risk prediction in patients with PTCL and can help inform patient counseling, biomarker discovery, clinical trial design, and precision medicine approaches,” wrote Matthew J. Maurer, MS, of the Mayo Clinic, Rochester, MN, and his coauthors (J Clin Oncol. 2017 Oct 26. doi: 10.1200/JCO.2017.73.8195).
PTCL is an uncommon and heterogeneous group of non-Hodgkin lymphomas that carry a very poor prognosis; most systemic cases are treated with anthracycline-based combination chemotherapy. Previous studies have reported that achieving EFS24 is predictive of excellent long-term outcomes, independent of baseline prognostic factors.
In this study Mr. Maurer and his coauthors assessed the association between EFS24 and overall survival in 775 patients with newly systemic PTCL who were diagnosed during 2000-2012 and received treatment with curative intent.
Among the entire cohort, 36% of patients achieved EFS24 while 64% did not, and the median overall survival following progression within that 2-year time period was 4.9 months (95% confidence interval, 3.8-5.9 months). The 5-year overall survival in the group that relapsed was 11%, with a standardized mortality ratio of 46.4 (95% CI, 41.8-51.3).
Conversely, among patients with EFS24, the median overall survival was not reached, and the 5-year overall survival was 78% (95% CI, 73%-84%). In this group, the 5-year risk of subsequent lymphoma relapse was 23%, and survival following a late relapse was generally poor (median of 10.3 months; 95% CI, 5.7-19.1 months). The best outcomes after achieving EFS24 were observed among patients aged 60 years or younger: These patients had a 5-year overall survival of 91%.
“The use of a dichotomous end point that allows individualized risk prediction is particularly important in rare diseases such as PTCL, where limited numbers of patients may make formal surrogate end point analysis difficult,” wrote the authors.
The study was supported by grants from the National Cancer Institute, the Terry Fox Research Institute, and the BC Cancer Foundation. Dr. Maurer reported research funding from Kite Pharma and Celgene, and several of the coauthors reported relationships with industry.