Patients with severe hirsutism, virilization, or recent and rapidly progressing signs of androgen excess require careful investigation for the presence of an androgen-secreting neoplasm. The two most common sources of androgen-secreting tumors are the adrenal glands and the ovaries. To assess the symptoms, serum and urine tests for androgens and their metabolites should be obtained along with modern abdominal imaging techniques such as CT, MRI, and ultrasound scans (194). In prepubertal girls, virilizing tumors may cause signs of heterosexual precocious puberty in addition to hirsutism, acne, and virilization. In patients suspected of harboring an adrenal or ovarian tumor because of rapidly progressing or severe hyperandrogenism, the bioavailable testosterone level (free testosterone level above 6.85 pg/mL; 23.6 pmol/L), followed by an11-desoxycortisol (above 7 ng/mL; 20.2 nmol/L), DHEAS (>3.6 μg/mL) and a 24-hour urinary cortisol (>45 μg per day) are the most sensitive and specific for the detection of an androgen-secreting adrenocortical tumor (Table 31.3). A markedly elevated free testosterone level (2.5 times the upper normal range) is considered typical of an adrenal androgen-secreting tumor, while moderately elevated free testosterone levels are often ovarian in origin. A DHEAS level greater than 800 μg/dL is typical of an adrenal tumor. An adrenal tumor is unlikely when serum DHEAS and urinary 17-ketosteroid excretion measurements are in the normal basal range and the serum cortisol concentration is less than 3.3 μg/dL after dexamethasone administration (195). The results of other dynamic tests, especially testosterone suppression and stimulation, are unreliable (196).
A vaginal and abdominal ultrasonographic examination is the first step in the evaluation of findings suggesting ovarian neoplasm. Duplex Doppler scanning may increase the accuracy of tumor diagnosis and localization (197).
CT scanning can reveal tumors larger than 10 mm (1 cm) in the adrenal gland but may not help to distinguish among different types of solid tumors or benign incidental nodules (198). In the ovaries, CT scanning cannot help differentiate hormonally active from functional tumors (197,198).
MRI is comparable, if not superior, to CT scanning in detecting ovarian neoplasms, but is neither more sensitive than high-quality ultrasound nor more useful in clinical decision making when ultrasound identifies a likely neoplasm. Nuclear medicine imaging of the abdomen and pelvis after injection with NP-59 ((131-iodine) 6-beta-iodomethyl-19-norcholesterol), preceded by adrenal and thyroid suppression, may facilitate tumor localization. In the rare circumstances when imaging fails to provide clear evidence for a neoplastic source of excess androgens, selective venous catheterization with measurement of site-specific androgen levels to identify an occult source of for androgen excess may be utilized (199). If all four vessels are catheterized transfemorally, selective venous catheterization allows direct localization of the tumor. Samples are obtained for hormonal analysis, with positive localization defined as a 5:1 testosterone gradient compared with lower vena cava values (200). Under such circumstances specificity approaches 80%, but this rate should be weighed against the 5% rate of significant complications, such as adrenal hemorrhage and infarction, venous thrombosis, hematoma, and radiation exposure (201).