SELF ASSESSMENT ANSWERS Testicular mass in a resting cell

An adrenal cortical cell rest, an interstitial cell, and a pleuripotent cell have all been suggested as the origin of testicular masses in congenital adrenogenital syndrome. 2 Embryologically the development of the adrenal gland and the genital ridge occurs in close proximity. Adrenal cell rests are therefore known to occur in the spermatic cord, testis, broad ligament, and the ovary. The normal pathway of synthesis of the steroids hormones is shown in fig 1. The commonest defect in adrenogenital syndrome or congenital adrenal hyperplasia is complete or partial deficiency of 21-hydroxylase followed by a deficiency of 11-b-hydroxylase. The enzyme 21-hydroxylase is crucial to the synthesis of both cortisol and aldosterone. A lack of this enzyme leads to excess synthesis of adrenal androgens and also stimulation of secretion of adrenocorticotrophic hormone (ACTH). This ACTH in turn acts on the adrenal tissue, including the ectopic adrenal cell rests leading to hyperplasia and formation of testicular masses in male patients. Hyperplasia of testicular adrenal rest cells is also known to occur in patients with Nelson’s syndrome who have undergone adrenalectomy of the native glands. Histologically the smaller lesions are located at the hilus in 86% as shown by Rutgers et al. The larger lesions are more commonly situated in the testicular parenchyma. They tend to be well demarcated, unencapsulated brown green masses separated into lobules by bands of fibrous tissue. Microscopically the most important differentiating feature from a Leydig cell tumour is the absence of renke crystals. 2 5 Clinically adrenogenital syndrome exists in three forms—that is, prenatal virilisation with or without salt wasting, a late onset form, and an asymptomatic form. The testicular masses occur more commonly in the salt loosing form. They need not always be clinically palpable. These patients with congenital adrenal hyperplasia are prone to infertility secondary to impaired spermatogenesis and Leydig cell failure, both in the testicular masses group as well as in patients with no testicular masses. Treatment with hormone replacement (dexamethasone) is shown to reduce the size of these lesions as well as a reduction in the hardness of the testis. Compliance with treatment is shown to prevent their occurrence. 9 A lack of decrease in size with compliance to treatment is also seen and can be secondary to extensive fibrosis or calcification in the lesions at diagnosis. However a study by Stikkelbroeck et al showed no significant correlation of the tumour size to the hormone replacement regimens or under treatment of these patients.