Interim FDG PET/CT in Diffuse Large B Cell Lymphoma (DLBCL) Patients

Newly diagnosed diffuse large B cell lymphoma (DLBCL) patients who enter this study will receive baseline fluorodeoxyglucose (FDG) positron emission tomography (PET) computed tomography (CT) scan at the time of initial staging. The patients will be diagnosed and undergo initial staging according to The Catholic University Lymphoma Group (CULG) Protocol. After 1 cycle of rituximab plus cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP) chemotherapy, early interim FDG PET/CT will be obtained after the patient recovers from nadir (usually 13 to 16 days after) following the administration of first cycle of R-CHOP,immediately before the second cycle of R-CHOP. The result of early interim FDG PET/CT study will not impact patient management, except in rare case where newly developed lesion is found and biopsy confirmed. The same PET/CT system and analysis software will be used for all scans from baseline to surveillance for all patients enrolled in this study. After 3 cycles of R-CHOP, a mid-therapy interim FDG PET/CT will be obtained. Patients with newly developed lesion will receive different chemotherapy regimen, while patients with stable disease, partial metabolic response or complete metabolic response will continue to receive 3 more cycles of R-CHOP. After the completion of 6 cycles of R-CHOP, the patients will receive a FDG PET/CT scan for response assessment. Selected patients with persistent disease or very bulky tumor volume on initial staging images will receive additional radiation therapy. The patients will be followed up every 3 months for 2 years from beginning of therapy. Physical examination and lab studies will be done usually every 3 months. Imaging studies will be performed every 3 months alternating between enhanced CT and FDG PET/CT and noted when different schedule is applied for surveillance. The end points are changes in FDG uptake measurements between the baseline and early interim FDG PET/CT, and between baseline and mid-therapy interim FDG PET/CT scans; response assessment following completion of 6 cycles of R-CHOP with or without radiation therapy assessed by International Workshop Criteria (IWC)+PET and PET Response Criteria in Solid Tumors (PERCIST) guideline; and the 2 year disease free survival.

Change in summed SULpeak between baseline FDG PET/CT before chemotherapy and mid-therapy interim FDG PET/CT after 3 cycles in DLBCL patients

baseline and 3 cycles after starting chemotherapy, approximately 49 to 57 days after beginning R-CHOP

Change in summed SULpeak between baseline FDG PET/CT before chemotherapy and early interim FDG PET/CT after 1 cycle of R-CHOP in DLBCL patients

Patients considered to have 2 year disease free survival will be those with complete response after 6 cycles of R-CHOP or isolated persistent disease treated by radiation therapy, AND continuous disease free state for 2 years from the start of therapy (reference standard "success"). All other patients will be considered to not have achieved 2 year disease free survival.

Response according to Lugano Classification and Deauville 5 point score. Response according to IWC+PET criteria with qualitative visual analysis of FDG PET/CT using mediastinum as the background reference.

after chemotherapy with or without radiation therapy is finished, approximately 120 to 210 days after beginning R-CHOP

Response according to PERCIST criteria with change in summed SULpeak in the FDG PET/CT as the background reference.

after chemotherapy with or without radiation therapy is finished, approximately 120 to 210 days after beginning R-CHOP

Inclusion Criteria: CD20+ diffuse large B cell lymphoma confirmed Therapy naïve for lymphoma 19 years or older Written informed consent Exclusion Criteria: Cannot understand informed consent Age under 19 years old Previous chemotherapy or radiation therapy for lymphoma Known pregnancy or urine/serum hCG (+) Unable to lie down still on back for about 30 minutes

Wahl RL, Jacene H, Kasamon Y, Lodge MA. From RECIST to PERCIST: Evolving Considerations for PET response criteria in solid tumors. J Nucl Med. 2009 May;50 Suppl 1(Suppl 1):122S-50S. doi: 10.2967/jnumed.108.057307.

Michallet AS, Trotman J, Tychyj-Pinel C. Role of early PET in the management of diffuse large B-cell lymphoma. Curr Opin Oncol. 2010 Sep;22(5):414-8. doi: 10.1097/CCO.0b013e32833d5905.

Zelenetz AD, Abramson JS, Advani RH, Andreadis CB, Byrd JC, Czuczman MS, Fayad L, Forero A, Glenn MJ, Gockerman JP, Gordon LI, Harris NL, Hoppe RT, Horwitz SM, Kaminski MS, Kim YH, Lacasce AS, Mughal TI, Nademanee A, Porcu P, Press O, Prosnitz L, Reddy N, Smith MR, Sokol L, Swinnen L, Vose JM, Wierda WG, Yahalom J, Yunus F. NCCN Clinical Practice Guidelines in Oncology: non-Hodgkin's lymphomas. J Natl Compr Canc Netw. 2010 Mar;8(3):288-334. doi: 10.6004/jnccn.2010.0021. No abstract available.