A Cure Rate Model with Discrete Frailty on Hodgkin Lymphoma Patients after Diagnosis

Introduction: Hodgkin lymphoma (HL) is an uncommon cancer of lymphocytes, characterized by cancerous Reed-Sternberg cells in an inflammatory background. HL is an exceptionally curable disease with combination chemotherapy, radiotherapy, or combined modality treatment. This analysis aimed to identify significant prognostic factors on the cure rate. Materials and Methods: The medical records of 110 patients hospitalized from 2007 up to 2014 with 18 months follow-up was retrospectively reviewed in Taleghani hospital of Tehran, Iran. The survival time was set as the time interval between diagnosis and a patient's death from HL. Also, if the cure rate was present in survival, data encompasses zero frailty. Thus, using hyper- Poisson (hP) distribution as discrete frailty, the unobserved heterogeneity and random effects were accounted for. Results: The estimated cure fraction was 81.2%, which was obtained after 2717 days (7.4 years). In noncured cases, the mean survival time was 1535 days (4.2 years). Also, the five and ten-year survival rates were 0.91 and 0.80, respectively. After diagnosis, results revealed that patients with age 45, hemoglobin 12, WBC 15000, and BMI 30 were associated with poor outcome by using simple analysis. More importantly, there is no significant difference between males and females in the cure of HL patients. Conclusion: As expected, the study indicated that a high proportion of HL patients got cured. A cure rate model with discrete frailty utilization provided a suitable way to account for heterogeneity among HL patients.