Spontaneous regression of classical Hodgkin lymphoma: a case report and review of the literature.

Thomas Hodgkin first described Hodgkin lymphoma in 1832. Classical Hodgkin lymphoma (cHL) is a potentially curable hematologic malignancy with distinct histology, biologic behavior, and clinical characteristics. cHL is further divided into different subgroups, based on the appearance and immunophenotype of the tumor cells as well as the composition of the reactive background. Mixed-cellularity cHL represents 15–30% of cHL cases. The incidence rate of cHL is 2.8 per 100,000 men and women per year. It accounts for approximately 10% of all lymphomas and approximately 0.6% of all cancers diagnosed in the developed world annually.1,2 The improvement in 5-year survival is unmatched in the United States by any other cancer throughout the past 40 years. The overall 5-year relative survival rate is 84.7%. cHL has a bimodal age distribution, with one peak in the 20s and 30s and a second peak after the age of 50.3 cHL of the elderly is defined as that occurring in patients older than 60 years.4 It is an uncommon disease. Older patients usually present with mixed cellularity histology and B symptoms. Progression-free and overall survival rates for elderly cHL patients are disproportionately inferior to those of younger patients. Survival rates for elderly patients with cHL are inferior to those achieved by younger populations. The 5-year overall survival rates for elderly cHL patients range from 40–55%, as compared to overall survival rates exceeding 80–90% for patients younger than 40 years.5-7 Spontaneous regression (SR) of cancer is the complete or partial disappearance of a malignant tumor without treatment or in the presence of therapy that is