Steroid metabolism of a Sertoli cell tumour of the testis of a dog with feminization and alopecia and of the normal canine testis

The metabolism of [7α-3H]pregnenolone and [4-14C]dehydroepiandrosterone (DHA) by a Sertoli cell tumour of the testis from a dog with signs of feminization has been studied in vitro and compared with the metabolism of the normal canine testis.

The tumour formed oestrone and oestradiol-17β from DHA thus providing direct evidence for the synthesis of oestrogen by this type of neoplasm.

Relative or complete inactivity of several enzyme systems involved in the synthesis of testosterone was found in the tumour tissue, and the conversion of either precursor to testosterone was considerably less than in the normal testis.

Suggestive evidence is presented for the occurrence of steroid-specific 17α-hydroxylase and 3β-hydroxysteroid dehydrogenase-isomerase systems in canine testicular tissue.

The formation of sulphates of pregnenolone and DHA was shown both in normal and in neoplastic tissues and, in addition, the tumour either formed the sulphate of 17α-hydroxypregnenolone or caused the 17α-hydroxylation of pregnenolone sulphate.

The nature and classification of ovarian neoplasms

The classification of ovarian neoplasms on a histogenetic basis according to presentday concepts of development and structure of the ovary is considered. There are four histogenetic categories of primary ovarian tumours: neoplasms of germ cell origin, neoplasms of celomic (germinal) epithelium and its derivatives, neoplasms of specialized gonadal stroma (sex cords and mesenchyme), and neoplasms of non-specialized gonadal stromal and heterotopic elements. In patients of all ages, 70% of ovarian neoplasms were of celomic epithelial origin, 16% of germ-cell origin, 5% of specialized gonadal stromal origin, and 9% arose from the non-specialized stroma and heterotopic elements. Before 20 years of age, 59% of ovarian neoplasms were of germ cell origin and before puberty they accounted for 90% of all ovarian tumours. The different structural types of neoplasms within the four categories are described. Accurate classification of ovarian neoplasms on a histogenetic basis is stressed if proper treatment is to be given and intelligent assessment of end results is to be made.