Tissue measurements in senile sebaceous gland hyperplasia.

Senile sebaceous gland hyperplasia has been studied in 18 subjects in an attempt to shed some light on its pathogenesis. The sizes of different segments of the pilosebaceous unit were compared in senile sebaceous gland hyperplasia (SGH) and in control skin samples, using stereological techniques. The whole follicle was found to be significantly increased in volume compared with follicular structures in the control specimens. The size of differentiated sebaceous gland cells was found to be reduced compared with controls (490 +/- 72 microns 2 and 554 +/- 98 microns 2, respectively), but not significantly so. The mean tritiated thymidine autoradiographic labelling index determined in vitro was found to be decreased (5.42 +/- 1.79) compared with controls (7.48 +/- 2.44), but again, not significantly so. In addition the degree of solar elastotic degenerative change was found to be similar in SGH bearing skin compared with control samples. It is of interest that SGH and prostatic hypertrophy are exceptions to the usual atrophy of ageing and that both tissues are androgen dependent.