Nowakowski, G. S.

Background:Predicting early clinical failure in patients with untreated follicular lymphoma (FL) is important but difficult. Lymphoma involvement of extranodal (EN) sites is better detected by FDG‐PET/CT than CT alone, but PET parameters are not part of the usual predictive indices.Aims:We aimed to determine the incidence and patterns of EN and spleen disease, and learn if they were useful in predicting early clinical failure.Methods:PET/CT images from 613 cases of newly diagnosed FL between 2003 – 2016 were retrospectively reviewed for EN and spleen involvement. The location, number, and pattern of EN sites, as well as splenic involvement, were recorded. Associations with outcomes were assessed using event‐free survival (EFS), overall survival (OS), and early clinical failure at 24 months (EFS24).Results:49% (301/613) of patients had PET/CT‐detected EN involvement, and 28% (171/613) had spleen involvement. Presence of ≥2 EN sites, spleen, bone or soft tissue involvement all predicted failure to achieve EFS24. These factors, as well as pattern of bone involvement by imaging, were predictors of EFS on univariate analysis; presence of ≥2 EN sites and bone involvement pattern were also predictive of OS. In a multivariate analysis with FLIPI‐2 factors, spleen involvement, pattern of bone involvement, and soft tissue involvement independently predicted a lower EFS (Table 1). When the multivariate analysis was performed using PRIMA‐PI factors (marrow and B2 M), the presence of ≥2 EN sites was an adverse independent prognostic factor for OS (HR 2.28; 95% CI 1.01–5.18; p = 0.05).Table 1: Extranodal and spleen involvement by PET/CT as predictors of event‐free survival Summary/Conclusion:Baseline PET/CT identifies EN and spleen sites of disease that can predict early clinical failure in FL. These results, when combined with other factors, may better identify high‐risk patients and guide appropriate therapy.imageimage

We recently defined event‐free survival at 24 months (EFS24) as a clinically relevant outcome for patients with DLBCL. Patients who fail EFS24 have very poor overall survival, while those who achieve EFS24 have a subsequent overall survival equivalent to that of the age‐ and sex‐matched general population. Here, we develop and validate a clinical risk calculator (IPI24) for EFS24. Model building was performed on a discovery dataset of 1,348 patients with DLBCL and treated with anthracycline‐based immunochemotherapy. A multivariable model containing age, Ann Arbor stage, normalized serum LDH, ALC, ECOG performance status, bulky disease, and sex was identified. The model was then applied to an independent validation dataset of 1,177 DLBCL patients. The IPI24 score estimates the probability of failing to achieve the EFS24 endpoint for an individual patient. The IPI24 model showed superior discriminatory ability (c‐statistic = 0.671) in the validation dataset compared to the IPI (c‐statistic = 0.649) or the NCCN‐IPI (c‐statistic = 0.657). After recalibration of the model on the combined dataset, the median predicted probability of failing to achieve EFS24 was 36% (range, 12–88%), and the IPI24 showed an EFS24 gradient in all IPI groups. The IPI24 also identified a significant percentage of patients with high risk disease, with over 20% of patients having a 50% or higher risk of failing to achieve EFS24. The IPI24 provides an individual patient level probability of achieving the clinically relevant EFS24 endpoint. It can be used via electronic apps. Am. J. Hematol. 91:179–184, 2016. © 2015 Wiley Periodicals, Inc.