Interim and end ‐of‐treatment PET‐CT suffers from high false‐positive rates in DLBCL: Biopsy is needed prior to treatment decisions

PET ‐CT is a valid method to find DLBCL patient with insufficient treatment response but suffers from high false positive rates. Biopsy is needed before treatment decisions in PET positive patients. AbstractThe application of positron emission tomography (PET) ‐computed tomography (CT) in treatment response evaluation has increased in diffuse large B‐cell lymphoma (DLBCL), although its predictive value is controversial. We retrospectively analyzed the rate of false‐positive PET‐CTs performed as interim (n = 94) and end‐of‐treatment (n = 8) assessments among 102 DLBCL patients treated during 2010–2017 at Oulu University Hospital. In PET‐CT Deauville score ≥4 was regarded as positive. A biopsy was performed on 35 patients, and vital lymphoma tissue was detected from nine patients. Positive biopsy findings were associated w ith poor disease outcomes in this study. This difference was statistically significant: 2‐year failure‐free survival (FFS) was 44% in patients with a positive biopsy versus 83% for those with a negative biopsy (p = 0.003). The corresponding overall survival (OS) rates were 53% versus 95% (p = 0.010). In the multivariate analyses, a negative biopsy was an independent protective factor in FFS (Hazard Ratio (HR) 0.093 (95% confidence interval [CI] 0.017–0.511);p = 0.006) unrelated to the International Prognostic Index (IPI) (HR 1.139 [95% CI 0.237–5.474]p = 0.871) or stage (HR 1.365 [95% CI 0.138–13.470];p = 0.790). Th...
Source: Cancer Medicine - Category: Cancer & Oncology Authors: Tags: ORIGINAL RESEARCH Source Type: research