Using PET to guide treatment of DLBCL
Stained micrograph of a diffuse large B-cell lymphoma (DLBCL)
M Kadin, ASH Image Bank. 2011; 2011-2076. © American Society of Hematology
A Phase II Trial of PET-Directed Therapy for Limited Stage Diffuse Large B-Cell Lymphoma (DLBCL)
The S1001 lymphoma trial is one in a series of phase II trials SWOG has conducted in diffuse large B-cell lymphoma (DLBCL) patients to try to identify promising regimens for phase III comparison with the standard treatment of three cycles of R-CHOP therapy (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) followed by involved field radiotherapy (IFRT).
S1001 investigators use results of a PET/CT scan taken after three cycles of R-CHOP to determine the course of continued treatment for the newly diagnosed DLBCL patient.
Patients whose PET/CT scans come back negative for disease at this point in their treatment will get one more cycle of R-CHOP therapy. Those whose scans are positive will move to IFRT followed three to six weeks later by a course of yttrium-90 ibritumomab tiuxetan (Zevalin).
Translational medicine: Prognostic value of gene expression signatures in DLBCL
There is some evidence suggesting that three specific gene expression signatures predominate in limited stage DLBCL, which could account for the more favorable prognosis for limited stage disease as compared to advanced stage disease. S1001 will conduct gene profiling of formalin-fixed, paraffin-embedded tissue from each patient's initial biopsy to prospectively test this hypothesis.
"Our hypothesis is that intensifying treatment in the poor-risk group with positive PET/CT will improve their outcomes, while reducing treatment in the low-risk group with negative PET/CT will decrease toxicity and thus possibly also improve their outcomes," says Daniel O. Persky, M.D., of the Yale Cancer Center, who is lead study coordinator for S1001.
Five-year progression-free survival (PFS) rate is the primary endpoint being assessed.
Investigators will also look for differences in outcomes in patients diagnosed with limited stage DLBCL by CT scan who were then upstaged to an advanced DLBCL diagnosis by PET/CT scan. Patients in this subgroup will be enrolled in a parallel treatment arm and will get six cycles of R-CHOP therapy without radiation.
The study is available to all SWOG members, CCOPs, and affiliate sites and has been endorsed by sister groups CALGB (the Alliance) and ECOG-ACRIN.
Patients with biopsy proven DLBCL, identified as non-bulky Stage I or II at time of diagnostic CT scan (even if subsequent FDG-PET scan has upstaged it to Stage III or IV), may be eligible.
Please review the detailed eligibility criteria. Those interested in learning more about participation in the trial can find the nearest participating institution online or by contacting SWOG at (210) 614-8808 or at firstname.lastname@example.org.