AIDS-ASSOCIATED KAPOSIS-SARCOMA AND NON-HODGKINS-LYMPHOMAS REPORTING IN ITALY - A LINKAGE STUDY

To evaluate the completeness and accuracy in the reporting of AIDS-ass ociated Kaposi's sarcoma (KS) and non-Hodgkin's lymphomas (NHL) in Ita ly, a linkage study of the notifications to the Italian AIDS Registry (RAIDS-the national compulsory AIDS surveillance system) and the clini cal and pathological records of the Italian Cooperative Group on AIDS- related tumors (GICAT-a nationwide voluntary reporting system for HIV- infected individuals who develop cancer) was carried out. A total of 2 88 cases of KS and 258 cases of NHL fulfilling the AIDS definition cri teria, histologically diagnosed by the GICAT centers between January 1 987 and March 1992, were matched with the 16,860 AIDS cases reported t o the RAIDS up to March 1993. The linkage procedure, based on name, ge nder, and date of birth, identified 276 cases of KS (96%) and 241 case s of NHL (93%) present in both files (''linked'' cases). The diagnosis of KS did not appear among the clinical manifestations of AIDS in the RAIDS file in 67 out of the 276 linked KS (24%), either with coincide nt dates of KS diagnosis and of case notification (19 cases) or when t he KS diagnosis followed by greater than or equal to 2 months the case notification to RAIDS (48 cases). Of the 241 linked NHL, 84 (33%) had no such neoplastic complications of AIDS listed in the RAIDS tile, 23 with coincident dates of NHL diagnosis and of case notification and 6 1 with the NHL diagnosis made greater than or equal to 2 months after the notification. A noteworthy discrepancy in the classification of th e three histologic subtypes of NHL emerged between the GICAT and the R AIDS, The degree of underreporting of AIDS-associated cancers that eme rged from the present study suggests that augmentation with other sour ces of oncological information is important to better estimate the bur den of AIDS-related tumors and to study the interaction between HIV in fection and cancer.