- Patients with nonbulky diffuse large B-cell lymphoma (DLBCL) can be managed without radiation, with just 4 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) regimen based on the interim positron emission tomography (iPET)-negative scan.
Why this matters
- Patients with nonbulky DLBCL are typically treated using R-CHOP chemotherapy and subsequent radiotherapy.
- An effective radiation-free treatment course could potentially spare patients the pain, risks, time, and cost associated with radiotherapy.
- S1001 study: patients with nonbulky (
- Patients with an iPET-negative scan (Deauville scale 1-3) received an additional cycle of R-CHOP, whereas those with an iPET-positive scan (Deauville 4-5) received involved field radiation therapy (IFRT) + ibritumomab tiuxetan.
- Funding: Southwest Oncology Group.
- In the final analysis, 110 patients had iPET-negative and 14 had iPET-positive scans.
- Of the iPET-positive patients who received IFRT + ibritumomab tiuxetan (n=12), 67% had conversion of partial responses to complete responses, resulting in an overall complete response rate of 92%.
- At a median follow-up of 4.5 years, 5 patients had disease progression and 2 patients died from lymphoma.
- Overall 5-year PFS and OS rates were 87% and 90%.
- Survival outcomes were comparable for patients with iPET-negative vs iPET-positive scans:
- 5-year PFS: 88% vs 86%.
- 5-year OS: 91% vs 93%.
- Small number of patients with iPET-positive scan.
- Dr Catherine M Diefenbach, MD, director of the clinical lymphoma program at the Perlmutter Cancer Center, NYU Langone Health, New York City, said: “We cannot generalize ‘no radiation required’ for early stage DLBCL. We can say that for patients with limited stage nonbulky DLBCL who had no risk factors, if they are interim PET-negative (Deauville 3 or lower) after three cycles of R-CHOP that they should receive a fourth cycle of R-CHOP but do not require radiation.”