A lower incidence of Hodgkin's disease in Orientals has been recognized. Although most Hong Kong Chinese came from the Guangdong province of China, the incidence of Hodgkin's disease in Hong Kong Chinese is 9-2 per cent which is more comparable to the low figure of 6 per cent in Japan than the 32 per cent incidence in Guangdong. If this discrepancy in the ethnically similar populations is confirmed, other etiological or promoting factors must be considered. Ninety-two Hong Kong Chinese patients (54 males and 38 females) with Hodgkin's disease were reviewed. The median age was 34 years (range 5-79 years). The histology was lymphocyte predominant in nine (10 per cent), nodular sclerosing in 34 (37 per cent), mixed cellularity in 29 (3 1 per cent), lymphocyte depleted in nine (10 per cent) and unclassified in 11 (12 per cent). Seventeen per cent had stage Ia disease, 2 per cent Ib, 15 per cent IIa, 11 per cent IIb, 11 per cent IIIa, 9 per cent IIIb, 11 per cent IVa and 24 per cent IVb. Twenty-five of them (27 per cent) were staged by laparotomy. Twelve patients (13 per cent) had bulky disease. Identical to the pattern observed in Caucasians, our patients had an apparent biomodal age distribution, a male predominance and similar distribution of histological subtypes according to the Rye classification. The absence of an early peak in young adulthood and the lower incidence of the nodular sclerosing subtype reported in the Japanese was not observed in our patients.
A variety of treatments were given to the 92 patients. Most of the patients with stage 1-11 disease received radiotherapy except for those with B symptoms, bulky disease or lymphocyte depleted histology, who received chemotherapy with or without radiotherapy. All patients with stage III-IV disease received chemotherapy with or without radiotherapy except for two patients with stage IIIa disease who had total nodal irradiation only. The multivariate analysis revealed that Ann Arbor staging was a significant independent factor determining the disease-free survival of patients in complete remission and the overall survival of all patients. Age was the other independent variable significantly determining the overall survival.