GONADOBLASTOMA IN GONADAL DYSGENESIS - A REPORT OF 2 CASES WITH 46,XY/45,X MOSAICISM

Two cases of gonadoblastoma with 46,XY/45,X mosaicism are reported. The first patient had a female phenotype and presented at 13 years with stunting of growth and lack of pubertal manifestations. Gonadoblastoma, associated with undifferentiated fibrous tissue, was discovered at exploratory laparotomy. The second patient had an enlarged clitoris at birth. She was seen at 15 years because of growth failure and virilism. Plasma testosterone values and metabolic clearance rate were half those of male adults. Gonadoblastoma was associated with abnormal testicular tissue. High alkaline phosphatase activity, characteristic of undifferentiated embryonic germ cells, was conspicuous both in the gonadoblastoma nests and in the residual testicular tissue of the second patient. © 1969 The C. V. Mosby Company.