Prospective International Cohort Study Demonstrates Inability of Interim PET to Predict Treatment Failure in Diffuse Large B-Cell Lymphoma

Journal of Nuclear Medicine

Rose Ann Padua¹  Monica Celli¹  Robert Carr¹  Charity Gorospe¹  Tim P. Morris¹  Sumeet Gujral¹  Francisca Redondo¹  Maurizio Dondi¹  Reena Nair¹  Chirayu Auewarakul¹  June-Key Chung¹  Stefano Fanti¹  Diana Paez¹  Isinsu Kuzu¹  the IAEA Lymphoma Study Group¹  Tamás Györke¹  Juliano Cerci¹  Claudio Meneghetti¹ 

关键词: diffuse large B-cell lymphoma;    positron emission tomography;    prospective observational study;    risk stratification;    risk-adapted therapy;   

DOI  :  10.2967/jnumed.114.145326

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

The International Atomic Energy Agency sponsored a large, multinational, prospective study to further define PET for risk stratification of diffuse large B-cell lymphoma and to test the hypothesis that international biological diversity or diversity of healthcare systems may influence the kinetics of treatment response as assessed by interim PET (I-PET). Methods: Cancer centers in Brazil, Chile, Hungary, India, Italy, the Philippines, South Korea, and Thailand followed a common protocol based on treatment with R-CHOP (cyclophosphamide, hydroxyadriamycin, vincristine, prednisolone with rituximab), with I-PET after 2–3 cycles of chemotherapy and at the end of chemotherapy scored visually. Results: Two-year survivals for all 327 patients (median follow-up, 35 mo) were 79% (95% confidence interval [CI], 74%–83%) for event-free survival (EFS) and 86% (95% CI, 81%–89%) for overall survival (OS). Two hundred ten patients (64%) were I-PET–negative, and 117 (36%) were I-PET–positive. Two-year EFS was 90% (95% CI, 85%–93%) for I-PET–negative and 58% (95% CI, 48%–66%) for I-PET–positive, with a hazard ratio of 5.31 (95% CI, 3.29–8.56). Two-year OS was 93% (95% CI, 88%–96%) for I-PET–negative and 72% (95% CI, 63%–80%) for I-PET–positive, with a hazard ratio of 3.86 (95% CI, 2.12–7.03). On sequential monitoring, 192 of 312 (62%) patients had complete response at both I-PET and end-of-chemotherapy PET, with an EFS of 97% (95% CI, 92%–98%); 110 of these with favorable clinical indicators had an EFS of 98% (95% CI, 92%–100%). In contrast, the 107 I-PET–positive cases segregated into 2 groups: 58 (54%) achieved PET-negative complete remission at the end of chemotherapy (EFS, 86%; 95% CI, 73%–93%); 46% remained PET-positive (EFS, 35%; 95% CI, 22%–48%). Heterogeneity analysis found no significant difference between countries for outcomes stratified by I-PET. Conclusion: This large international cohort delivers 3 novel findings: treatment response assessed by I-PET is comparable across disparate healthcare systems, secondly a negative I-PET findings together with good clinical status identifies a group with an EFS of 98%, and thirdly a single I-PET scan does not differentiate chemoresistant lymphoma from complete response and cannot be used to guide risk-adapted therapy.

【 授权许可】

Unknown