Lymphocyte predominant Hodgkin's disease: pathology and clinical implication.
The special nature and course of lymphocyte rich variants of Hodgkin's disease (HD) has been the subject of pathological and clinical studies since the 1930s. Patients with lymphocyte predominant (LP) HD, predominantly male and 25-45 years old, usually present with early clinical stage, cervical or inguinal involvement and few if any adverse prognostic factors. The disease progresses slowly, with fairly frequent relapses which are rarely fatal. Nonetheless, cases with advanced stage and deaths from Hodgkin's disease have been observed in LPHD. Recently, immunological studies have lead to a clear distinction between LPHD and classical HD including a lymphocyte rich classical version (LRCHD). Secondary low-grade NHLs occur more frequently after LPHD than after classical HD. They seem to be disease-related rather than treatment-induced. LPHD patients in earlier studies have tended to have a better prognosis than classical HD patients. When cohorts of the same clinical stage are compared, under modern protocol treatment this advantage seems to be minimal or absent. LPHD patients tend to relapse frequently but they survive these relapses better than classical HD patients. The resemblance to non-neoplastic disorders, capability for ongoing mutation, favorable clinical presentation and good survival rates after relapse all suggest that the optimal primary treatment strategy might be less intensive for LPHD than for classical HD. Late toxicities, which contribute considerably to the death rate, could thus be reduced. The long survival of several early stage LPHD patients without any treatment beyond lymph node excision could favour a 'watch-and-wait' strategy, albeit only after rigorous staging. New experimental therapy techniques such as immunotherapy might also be suitable. These possibilities must first be tested in a large-scale prospective study.