Testicular adrenal rest tissue and male fertility in CAH
Hedi Claahsen-van der Grinten1, Barto Otten1, Fred Sweep3 & Ad Hermus2
Infertility is a serious problem in female as well in male CAH patients. The most important cause of male infertility in CAH patients is the presence of testicular adrenal rest tumors (TART). The reported prevalence in adult CAH patients is up to 96%. TART have no malignant features but because of their typical localization near the mediastinum testis, longstanding compression of the seminiferous tubules may lead to obstructive azoospermia and irreversible damage of testicular tissue. TART contain adrenal specific enzymes and produce adrenal specific hormones suggesting that these tumors consist of adrenal-like cells, which may nestle in the developing testis in the early embryonal period. The presence at the mRNA level of ACTH and angiotensin II (AII) receptors in these tumors support this hypothesis. Therefore, it is thought that elevated ACTH and AII levels as in poor hormonal control contribute to tumor growth.
Furthermore, adrenal rest cells may already be stimulated in utero when ACTH levels are elevated. The prevalence of TART in infancy is not yet studied in detail but in CAH children above 5 years old the prevalence of TART is up to 24%. Probably this prevalence is underestimated because very small tumors are only detectable by scrotal ultrasound, not routinely performed in all centers.
Treatment options of TART are still controversial. In some patients intensifying glucocorticoid therapy will lead to reduction of the tumor size by suppression of ACTH secretion. However, high doses of glucocorticoids may have serious side effects. Testis sparing surgery may be performed before irreversible damage is present. However, it is controversial whether testis-sparing surgery can be performed without causing additional gonadal damage.
1. Stikkelbroeck et al. J Clin Endocrinol Metab 2001 86 5721.
2. Claahsen-van der Grinten HL et al. Best Pract Res Clin Endocrinol Metab 2009 23 (2) 209220.