Computed Tomography Scans Do Not Improve the Predictive Power of 1996 National Cancer Institute–Sponsored Working Group Chronic Lymphocytic Leukemia Response Criteria

Abstract

National Cancer Institute-sponsored Working Group (NCI-WG) response criteria for chronic lymphocytic leukemia (CLL) rely on physical examination, blood, and bone marrow evaluations. The widespread use of computed tomography (CT) scans has prompted many to advocate for the incorporation of this test into CLL response criteria. In a retrospective review of 82 CLL patients treated at the Ohio State University (Columbus, OH), we compared CT assessed response using non-Hodgkin's lymphoma (NHL) response definitions with NCI-WG response. Responses by NCI-WG criteria included five complete responses (CRs), 32 partial responses (PRs), 21 patients with stable disease (SD), 17 patients with progressive disease (PD), and seven patients not assessable (NA). Responses by NHL-CT criteria included three CRs, 12 unconfirmed CRs (CRus), 16 PRs, 26 with SD, four with PD, and 21 NA. Using NCI-WG criteria, progression-free survival (PFS) was 27.3 months for CR and 11.4 months for PR. With NHL-CT criteria, PFS was 18.4 months for CR, 11.7 months for CRu, and 14.5 months for PR. In multivariate analysis, both NCI-WG and NHL-CT response correlated with PFS (P = .009 and .001, respectively). Current NCI-WG CLL response criteria are a significant predictor of PFS in previously treated CLL patients, with no additional benefit from the inclusion of CT scans. Although retrospective, these results highlight the importance of prospective validation of CT scans before routine inclusion in CLL response criteria.