LAUSR

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a distinct lymphoid malignancy accounting for ∼5% of all Hodgkin lymphoma cases. As the diseasedefining lymphocyte predominant cells consistently express CD20, CD20-directed approaches represent a treatment option in this entity [1]. Single-agent anti-CD20 antibody treatment has been evaluated in several phase II studies. Response rates were in excess of 90%. However, disease recurrence was common [2–5]. This was also true for individuals with newly diagnosed stage IA NLPHL who had received four weekly standard doses (375 mg/m) of the first-generation anti-CD20 antibody rituximab within a prospective study conducted by the German Hodgkin Study Group (GHSG). At a median observation time of 43 months, relapse had occurred in 7/28 patients (25%) [2]. We herein report a follow-up analysis of this study investigating the long-term course of the individuals treated within the trial protocol. It was also evaluated whether the histopathological growth pattern according to Fan et al. (typical growth pattern, i.e., growth pattern A and B vs. variant histology, i.e., growth pattern C to F) had impact on the patient ́s outcome [6]. Previous studies had indicated more advanced disease at diagnosis and an increased relapse rate for patients with a variant histology as compared with patients with a typical growth pattern [7, 8]. Follow-up data from the 28 patients who had been taken into account for the initial analysis of the study were requested from the participating sites. Progression-free survival (PFS) (defined as the time between the completion of the initial staging and NLPHL recurrence or death from any cause and censored at the date of last information on the disease status) and overall survival (OS) (defined as the time between the completion of the initial staging and death from any cause and censored at the date of last information for surviving patients) estimates were calculated using the Kaplan–Meier method. Parameters such as time to relapse and treatment at relapse were evaluated and described. Available biopsies from the initial NLPHL diagnosis were collected and the histopathological growth pattern according to Fan et al. was determined by a panel of expert hematopathologists [6]. Inclusion criteria, endpoints and study treatment have been reported elsewhere [2]. The study was conducted in accordance with the Declaration of Helsinki and was approved by the review boards of the participating sites. It was registered at www.clinicaltrials.gov as #NCT00346684. Baseline patient characteristics were reported previously. In brief, patients were mostly male (71%), the median age was 40 years and the majority had supradiaphragmatic disease (72%) [2]. Biopsies from the initial NLPHL diagnosis were available for 26/28 patients (93%). In 19/26 cases (73%), patients had a typical growth pattern, whereas 7/26 patients (27%) presented with a variant histology (Table 1). Patient characteristics were thus largely in line with earlier reports [7, 9]. At a median observation time of 9.7 years (interquartile range: 5.9–11.3 years), 10-year PFS and OS estimates were 51.1% (95% confidence interval: 29.7–69.0%) and 91.0% * Andreas Engert [email protected]