[Primary double neoplasias (author's transl)].

: Data of 22 patients with primary double tumors are reviewed, collected from a total of 39.000 clinical protocols of which 1.168 were malignant. All were histologically verified. Criteria were those established by Warren & Gates i.e. a) each tumor must present clear signs of malignancy, b) each tumor must be different from the other, c) all possibility that one tumor may be a metastasis of the other must be excluded. Twelve of the cases were male and 10 female, representing 1.88% of the total with malignancies. In 6 cases both tumors appeared simultaneously, while the time interval was between 1 and 43 years in the remaining 16. Hematologic neoplasias are predominant with 12/44, followed by digestive and urogenital ones with 8/44 in each sub-group. Association between double tumors is assessed and causal factors which may influence or favor the appearance of two or more neoplasias are discussed.