Strikingly high false positivity of surveillance FDG‐PET/CT scanning among patients with diffuse large cell lymphoma in the rituximab era

• Published in: American journal of hematology Vol. 88; no. 5; pp. 400 - 405
• Main Authors: Avivi, Irit, Zilberlicht, Ariel, Dann, Eldad J., Leiba, Ronit, Faibish, Tal, Rowe, Jacob M., Bar‐Shalom, Rachel
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.05.2013
• Subjects: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal, Murine-Derived - administration & dosage; Antibodies, Monoclonal, Murine-Derived - adverse effects; Antibodies, Monoclonal, Murine-Derived - therapeutic use; Antineoplastic Agents - administration & dosage; Antineoplastic Agents - adverse effects; Antineoplastic Agents - therapeutic use; Antineoplastic Combined Chemotherapy Protocols - administration & dosage; Antineoplastic Combined Chemotherapy Protocols - adverse effects; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Cohort Studies; Combined Modality Therapy; Cyclophosphamide - administration & dosage; Cyclophosphamide - adverse effects; Cyclophosphamide - therapeutic use; Doxorubicin - administration & dosage; Doxorubicin - adverse effects; Doxorubicin - therapeutic use; False Negative Reactions; Female; Fluorodeoxyglucose F18; Follow-Up Studies; Hematology; Humans; Lymphoma, Large B-Cell, Diffuse - diagnosis; Lymphoma, Large B-Cell, Diffuse - drug therapy; Lymphoma, Large B-Cell, Diffuse - pathology; Lymphoma, Large B-Cell, Diffuse - radiotherapy; Male; Middle Aged; Multimodal Imaging; Positron-Emission Tomography; Predictive Value of Tests; Prednisone - administration & dosage; Prednisone - adverse effects; Prednisone - therapeutic use; Radiopharmaceuticals; Recurrence; Remission Induction; Retrospective Studies; Rituximab; Tomography, X-Ray Computed; Vincristine - administration & dosage; Vincristine - adverse effects; Vincristine - therapeutic use
• ISSN: 0361-8609; 1096-8652
• DOI: 10.1002/ajh.23423

Predictive value (PV) of surveillance fluorodeoxyglucose positron emission tomography (FDG‐PET) in patients with diffuse large B‐cell lymphoma (DLBCL) treated with chemotherapy‐rituximab (R) versus chemotherapy only, remains unclear. The aim of the current study was to compare the performance of surveillance PET in DLBCL patients receiving CHOP (cyclophosphamide, hydroxydaunorubicin hydrochloride, vincristine, and prednisone) alone versus CHOP‐R. Institutional database was retrospectively searched for adults with newly diagnosed DLBCL, receiving CHOP or CHOP‐R, who achieved complete remission and underwent surveillance PETs. Follow‐up (FU) PET was considered positive for recurrence in case of an uptake unrelated to physiological or known benign process. Results were confirmed by biopsy, imaging and clinical FU. One hundred nineteen patients, 35 receiving CHOP and 84 CHOP‐R, who underwent 422 FU‐PETs, were analyzed. At a median PET‐FU of 3.4 years, 31 patients relapsed (17 vs. 14, respectively; P = 0.02). PET detected all relapses, with no false‐negative studies. Specificity and positive PV (PPV) were significantly lower for patients receiving CHOP‐R vs. CHOP (84% vs. 87%, P = 0.023; 23% vs. 74%, P < 0.0001), reflecting a higher false‐positive (FP) rate in subjects receiving CHOP‐R (77% vs. 26%, P < 0.001). In the latter group, FP‐rate remained persistently high up to 3 years post‐therapy. Multivariate analysis confirmed rituximab to be the most significant predictor for FP‐PET. In conclusion, routine surveillance FDG‐PET is not recommended in DLBCL treated with rituximab; strict criteria identifying patients in whom FU‐PET is beneficial are required. Am. J. Hematol. 88:400–405, 2013. © 2013 Wiley Periodicals, Inc.