Survey of the eventual diagnosis in 600 cases referred for a second histological opinion after an initial biopsy diagnosis of Hodgkin's disease.

In a series of 600 cases of lymphadenopathy in which an initial histological diagnosis of Hodgkin's disease was reviewed in a reference laboratory this interpretation was confirmed in 317 cases (53%). In the 283 other cases the diagnosis of Hodgkin's disease was considered to be mistaken. The condition most frequently confused with Hodgkin's disease was chronic non-specific lymphadenitis. Reticulum cell sarcoma, metastatic tumours, infectious mononucleosis, dermatopathic lymphadenopathy, toxoplasmosis, and early sarcoidosis were also notably frequent among the conditions mistaken for Hodgkin's disease.