Hessol and colleagues reported a significantly greater incidence of Hodgkin disease in homosexual men with HIV infection [1]. An additional aspect not mentioned by them is the apparent high prevalence of the mixed cellularity (MC) and lymphocyte depletion (LD) subtypes of Hodgkin disease in patients with HIV infection [2]. We compared the distribution of histologic subtypes of Hodgkin disease among 92 patients with HIV infection, 75 of whom were intravenous drug users, collected within the network of the Italian Group on AIDS and Tumors (GICAT) with that seen among patients without HIV infection. The HIV-infected patients had a fourfold higher (95% CI, 2.9 to 5.1) frequency of MC subtype and a 12-fold higher (95% CI, 7.0 to 18.0) frequency of LD subtype, in contrast to an Italian series of 125 non-HIV-infected patients [3] and a larger series of 14 315 cases of Hodgkin disease from Europe and the United States [4]. A significant deficit of the nonspecific (NS) subtype of Hodgkin disease was also noted. The ratio between NS and MC plus LD histologic subtypes was 0.3 among the HIV-positive patients and 2.1 and 4.9 in the case series from Europe and the United States and Italy, respectively.

The findings of our study support the hypothesis that Hodgkin disease in HIV-infected patients has features distinct from those seen in the general population. In our series, composed predominantly of intravenous drug users, a significant increase in the number of patients with advanced stages of Hodgkin disease at presentation and lower complete response rates to chemotherapy have been observed when compared with patients without HIV infection. In addition, a significant HIV-related immunodeficiency has been found at the diagnosis of Hodgkin disease, as shown by a median CD4 count of 249/mm³. Possibly, Hodgkin disease of the MC or LD subtype in patients with HIV infection should be considered to be an AIDS-related malignancy.