Histopathological growth patterns in patients with advanced nodular lymphocyte-predominant Hodgkin lymphoma treated within the randomized HD18 study: a report from the German Hodgkin Study Group.

We retrospectively investigated histopathological growth patterns in individuals with advanced nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) treated within the randomized HD18 study. In all, 35/60 patients (58%) presented with atypical growth patterns. Patients with atypical growth patterns more often had stage IV disease (P = 0·0354) and splenic involvement (P = 0·0048) than patients with typical growth patterns; a positive positron emission tomography after two cycles of chemotherapy (PET-2) tended to be more common (P = 0·1078). Five-year progression-free survival [hazard ratio (HR) = 0·86; 95% confidence interval (CI) = 0·49-1·47] and overall survival (HR = 0·85; 95% CI = 0·49-1·51) did not differ between the groups after study treatment with PET-2-guided escalated BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone). Thus, advanced NLPHL is often associated with atypical growth patterns but their prognostic impact is compensated by PET-2-guided escalated BEACOPP.