Post-treatment (not interim) positron emission tomography-computed tomography scan status is highly predictive of outcome in mantle cell lymphoma patients treated with R-HyperCVAD.

BACKGROUND: Although convincing data exist regarding the prognostic utility of positron emission tomographic (PET)-computed tomographic (CT) imaging in Hodgkin lymphoma and diffuse large B-cell lymphoma, its prognostic utility both during treatment and immediately after treatment have not been systematically evaluated in a large mantle cell lymphoma (MCL) patient cohort to support its use in clinical practice.

METHODS: The authors conducted a retrospective cohort study to examine the prognostic utility of PET-CT imaging in a uniform MCL patient cohort undergoing dose-intensive chemotherapy (R-HyCVAD) in the frontline setting. The primary study endpoints were progression-free survival (PFS) and overall survival (OS). PET-CT images were centrally reviewed for the purposes of this study using standardized response criteria.

RESULTS: Fifty-three patients with advanced stage MCL with PET-CT data were identified. With median follow-up of 32 months, 3-year PFS and OS estimates were 76% (95% confidence interval [CI], 64%-84%) and 84% (95% CI, 72%-90%), respectively. Interim PET-CT status was not associated with PFS (hazard ratio [HR], 0.9; 95% CI, 0.3-2.7; P = .8) or OS (HR, 0.6; 95% CI, 0.1-2.9; P = .5). Post-treatment PET-CT status was statistically significantly associated with PFS (HR, 5.2; 95% CI, 2.0-13.6; P = .001) and trended toward significant for OS (HR, 2.8; 95% CI, 0.8-9.6; P = .07).

CONCLUSIONS: These data do not support the prognostic utility of PET-CT in pretreatment and interim treatment settings. A positive PET-CT after the completion of therapy identifies a patient subset with an inferior PFS and a trend toward inferior OS.