Tumours in Iceland. 13. Malignant tumours of the testis

Abstract

Data from 76 patients with malignant tumours of the testis registered with the Icelandic Cancer Registry during the period 1955-1984 were analyzed and classified histologically according to the WHO criteria. In 55 patients the tumours were of one histological type (72% of total). In the order of frequency, seminoma was diagnosed in 35 (46%), embryonal carcinoma in 14 (18%) and teratoma in 6 patients (8%). Twenty patients had tumours of more than one histological type (26%), i.e. a combination of embryonal carcinoma and teratoma (teratocarcinoma) in nine (12%) and combined tumours (seminoma component with other tumours) in seven (9%). Two patients had choriocarcinomas and three had yolk sac (endodermal sinus) tumours, both of them in combination with other neoplasms. Embryonal rhabdomyosarcoma was the only malignant non-germ cell tumour diagnosed. The age-adjusted incidence of malignant testis tumours increased by 48% from 1.6 per 100,000 per annum in 1955-1964 to 3.1 per 100,000 in 1975-1984. The increase affected both seminoma and non-seminomatous tumours (NSGCT). There has been an improvement in survival with time. Sixteen deaths were related to testis tumours and all occurred within four years of diagnosis. The incidence of testicular tumours in Iceland is intermediate between "high risk" and "low risk" countries.