Bone marrow transplants undertaken after these therapies have failed, however, can significantly increase the survival rates of these patients, researchers said.
The study, “The Outcome Of Peripheral T-Cell Lymphoma Patients Failing First Line Therapy: A Report From The Prospective, International T-Cell Project,” was published in the journal Haemtologica.
Mature or peripheral T-cell lymphomas (PTCL) comprise a diverse group of rare T-cell cancers characterized by poor prognosis.
Current first-line treatment strategies include a chemotherapy regimen such as CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or similar treatments. Only 50-65 percent of patients achieve remission, and for most patients, the risk of relapse is quite high. Relapsed patients typically have poor outcomes.
The International T-cell Project (NCT01142674) is a prospective, observational cohort study taking place across four continents and 74 academic centers. The study is still currently recruiting, with an estimated enrollment of 2,000 patients.
As part of this study, researchers collected data on clinical characteristics, treatments, and outcomes from 1,020 patients. They also analyzed the data to explore factors that influence the survival of patients with primary refractory or relapsed PTCL.
Among the 937 patients who received first-line treatment, 436 were refractory — meaning not responsive to treatment — and 197 relapsed. The median time from the end of treatment to relapse was eight months.
Patients were followed for a median of 38 months from the time of refractory/relapse, during which 440 patients died. Median overall survival was 5.8 months with a three-year survival rate of 21% for patients with refractory disease and 28% for those who relapsed.
“Results confirm that peripheral T-cell lymphomas patients had dismal outcome after relapse or progression,” the investigators wrote.
Patients who received bone marrow transplants, totaling 75 patients, demonstrated a three-year survival rate of 48%, which was significantly higher than the 18% seen in patients that did not receive bone marrow transplants.
Using statistical analysis, researchers demonstrated that refractory disease was associated with a 1.43 times higher risk of death. On the other hand, a later time of relapse — defined as more than 12 months — was associated with a more than 40% reduced risk of death. Bone marrow transplants were also associated with a more than a 60% reduction in risk of death.
“We demonstrated that the outcomes are worse for patients with refractory disease and that the SAR [survival after relapse] at 3 years for these patients was only 21%. We also found that late relapse and consolidation with HCT were associated with a longer survival in chemotherapy sensitive patients,” the researchers concluded.
These data underscore the need for new treatments for these patients, and researchers hope this analysis can be useful in the future to determine the effectiveness of future potential therapies.