End-of-treatment and serial PET imaging in primary mediastinal B-cell lymphoma following dose-adjusted EPOCH-R: a paradigm shift in clinical decision making
Christopher Melani,
Ranjana Advani,
Mark Roschewski,
Kelsey M. Walters,
Clara C. Chen,
Lucia Baratto,
Mark A. Ahlman,
Milos D. Miljkovic,
Seth M. Steinberg,
Jessica Lam,
Margaret Shovlin,
Kieron Dunleavy,
Stefania Pittaluga,
Elaine S. Jaffe,
Wyndham H. Wilson
Affiliations
Christopher Melani
Lymphoid Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
Ranjana Advani
Stanford Cancer Institute, Stanford University, CA
Mark Roschewski
Lymphoid Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
Kelsey M. Walters
Stanford Cancer Institute, Stanford University, CA
Clara C. Chen
Nuclear Medicine Division, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD
Lucia Baratto
Nuclear Medicine and Molecular Imaging Division, Stanford University, CA
Mark A. Ahlman
Nuclear Medicine Division, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD
Milos D. Miljkovic
Lymphoid Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
Seth M. Steinberg
Biostatistics and Data Management Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
Jessica Lam
Stanford Cancer Institute, Stanford University, CA
Margaret Shovlin
Lymphoid Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
Kieron Dunleavy
George Washington University Cancer Center, DC
Stefania Pittaluga
Laboratory of Pathology, Clinical Center, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
Elaine S. Jaffe
Laboratory of Pathology, Clinical Center, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
Wyndham H. Wilson
Lymphoid Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
Dose-adjusted-EPOCH-R obviates the need for radiotherapy in most patients with primary mediastinal B-cell lymphoma. End-of-treatment PET, however, does not accurately identify patients at risk of treatment failure, thereby confounding clinical decision making. To define the role of PET in primary mediastinal B-cell lymphoma following dose-adjusted-EPOCH-R, we extended enrollment and follow up on our published phase II trial and independent series. Ninety-three patients received dose-adjusted-EPOCH-R without radiotherapy. End-of-treatment PET was performed in 80 patients, of whom 57 received 144 serial scans. One nuclear medicine physician from each institution blindly reviewed all scans from their respective institution. End-of-treatment PET was negative (Deauville 1-3) in 55 (69%) patients with one treatment failure (8-year event-free and overall survival of 96.0% and 97.7%). Among 25 (31%) patients with a positive (Deauville 4-5) end-of-treatment PET, there were 5 (20%) treatment failures (8-year event-free and overall survival of 71.1% and 84.3%). Linear regression analysis of serial scans showed a significant decrease in SUVmax in positive end-of-treatment PET non-progressors compared to an increase in treatment failures. Among 6 treatment failures, the median end-of-treatment SUVmax was 15.4 (range, 1.9-21.3), and 4 achieved long-term remission with salvage therapy. Virtually all patients with a negative end-of-treatment PET following dose-adjusted-EPOCH-R achieved durable remissions and should not receive radiotherapy. Among patients with a positive end-of-treatment PET, only 5/25 (20%) had treatment-failure. Serial PET imaging distinguished end-of-treatment PET positive patients without treatment failure, thereby reducing unnecessary radiotherapy by 80%, and should be considered in all patients with an initial positive PET following dose-adjusted-EPOCH-R (clinicaltrials.gov identifier 00001337).
