Ultrasonography of adrenal masses: unusual manifestations

Fine-needle aspiration cytology of adrenal masses: a re-assessment with histological confirmation

BACKGROUND

Fine-needle aspiration (FNA) of adrenal masses is a method currently indicated in lesions suspected of being extra-adrenal in origin; even though its diagnostic reliability has already been determined in many studies, few have used histological examination obtained after adrenalectomy for diagnostic confirmation.

AIM

To analyze the diagnostic performance of adrenal FNA in subjects with an available histological confirmation.

SUBJECTS AND METHODS

Fifty subjects (26 benign adrenal lesions, 9 primary malignant lesions, and 15 metastatic lesions) who had undergone ultrasound (US)-guided adrenal FNA and then adrenalectomy were re-analyzed retrospectively.

RESULTS

FNA guaranteed a sensitivity of 85.7% and a specificity of 100% in all subjects; after having divided the subjects into oncologic and non-oncologic groups, the sensitivity of the test in oncologic patients (100%) increased significantly compared to non-oncologic (57.1%) with no difference in specificity (100% in both groups). Considering also non-diagnostic samples in our analysis (no.=11; 22% of all samples studied), FNA correctly diagnosed malignancy only in 75% of the cases and benignancy only in 66.6%; however, even after including non-diagnostic samples, the percentage of correct malignancy diagnosis remained significantly higher in oncologic (93.3%) than in non-oncologic patients (44.4%) without significant statistical difference between the 2 groups regarding the percentage of correct benignancy diagnosis (respectively 100% and 63.6%).

CONCLUSIONS

Our study, based on histological confirmation, underlines the low discriminant value of US-guided adrenal FNA, though the method may have value in oncologic patients.

Adrenocortical neoplasms in children: radiologic-pathologic correlation

Primary neoplasms of the adrenal cortex are rare in children and differ significantly in epidemiology, clinical characteristics, and biologic features from their counterparts in adults. In children, the inclusive term adrenocortical neoplasm is applied because adrenal adenoma and adrenal carcinoma may be difficult to distinguish histopathologically. Pediatric adrenocortical neoplasms typically occur before 5 years of age, affect young girls more commonly than boys, and are associated with hemihypertrophy and Beckwith-Wiedemann and Li-Fraumeni syndromes. Most children with an adrenocortical neoplasm present with signs and symptoms of endocrine abnormality, including virilization and Cushing syndrome. Cross-sectional imaging studies typically demonstrate a large, circumscribed, predominantly solid suprarenal mass with variable heterogeneity due to hemorrhage and necrosis. Calcification is not uncommon. Local invasion and metastases to the lungs, liver, and regional lymph nodes may be present at diagnosis. When friable tumor thrombus extends into the inferior vena cava, it poses a high risk of pulmonary embolization. The finding of increased retroperitoneal fat due to hypercortisolism on computed tomographic and magnetic resonance images of children with an adrenal mass favors the diagnosis of adrenocortical neoplasm. Surgical resection is the mainstay of therapy, with chemotherapy used for patients with metastases or persistent elevated hormone levels following surgery. Patients younger than 5 years with aggressive adrenocortical neoplasms fare better than older children.

Adrenal gland and nonrenal retroperitoneum

Ultrasound, as the initial cross-sectional imaging technique, confirmed the value of axial records. Although computerized tomography and possibly magnetic resonance offers better resolution, ultrasonography has the advantage of being less expensive, convenient, and highly portable. With these specific indications and reservations, ultrasonography of the adrenal and retroperitoneum has an accepted role in imaging.

Ultrasonography of the normal adrenal glands: a study using linear-array real-time equipment

The adrenal glands were evaluated in 70 normal volunteers using linear-array real-time ultrasonography. All the scanning approaches described for manual B-scanning were used and, on the left side, longitudinal scans along the axillary lines were also performed. The right adrenal gland was imaged in 68 of the 70 volunteers and the left gland in 63. The dynamic capabilities of real-time equipment were of great help for proper localisation and identification of the glands. Changes in the scanning plane demonstrated variations in the adrenal morphology, because different portions of the gland were encountered by the scanning beam.

The adrenal cortex and virilization

The physiological control of adrenal androgen secretion has not been definitively established. However, there is evidence to suggest that a dexamethasone-suppressible factor other than ACTH may have a specific role to play. The majority of patients with idiopathic hirsutism (hirsutism associated with regular menstruation) have findings suggestive of adrenal androgen excess, including enhanced androgen responsiveness following administration of metyrapone, and respond to treatment with dexamethasone, 0.5 mg given each night. Patients with idiopathic hirsutism have elevated androgens but normal oestrogen and gonadotrophin levels. In contrast, while patients with polycystic ovary syndrome (PCOS) also demonstrate evidence of adrenal androgen excess, these patients have elevated oestrone levels and gonadotrophin secretion is abnormal. Approximately 50% of patients with PCOS treated with dexamethasone resume regular menstruation. Oestrone excess appears to be primary to the abnormal gonadotrophin secretion and to the development of PCOS. In non-obese patients with PCOS elevated oestrone appears to occur as a consequence of the availability of the excessive amounts of its immediate precursor, androstenedione, an androgen mainly of adrenal origin. Androstenedione is converted to oestrone in fat. Obese amenorrhoeic subjects have normal androstenedione values but elevated oestrone levels with abnormal gonadotrophin secretion as seen in PCOS. These findings indicate that abnormal gonadotrophin secretion is associated with elevated oestrone levels whether these occur as a consequence of excessive adrenal androgen secretion, or the excessive conversion of normal amounts of available androstenedione. Patients with idiopathic hirsutism and elevated androstenedione levels but normal oestrone values appeared to be protected against the development of PCOS by relatively poor conversion of androstenedione to oestrone. It is likely, therefore, that if patients with idiopathic hirsutism gain additional adipose tissue, elevated oestrone levels will result and PCOS will develop. These observations explain the frequent association of PCOS and obesity. There is a close clinical association between elevated androgen levels and hirsutism and between elevated oestrone levels and menstrual disturbances. However, some patients with amenorrhoea but without hirsutism may demonstrate marked elevations of androgens and oestrone, the correction of which leads to the resumption of regular ovulation. This presentation, 'amenorrhoea with cryptic hyperandrogenaemia', is probably explained by diminished sensitivity of androgen receptors.(ABSTRACT TRUNCATED AT 400 WORDS)

Real-time ultrasound of normal adrenal glands and small tumors

The adrenals were studied prospectively with real-time ultrasound in a series of 60 healthy individuals and 13 patients with small adrenal masses sized 8-20 mm in diameter. In only one of the 60 healthy subjects was a normal adrenal gland delineated as a distinct hypoechoic structure. In all other instances only the highly echogenic suprarenal fat could be displayed. Visualization of small tumors was successful in 12 of 13 patients. The suprarenal area and small lesions were best demonstrated by a lateral intercostal approach using longitudinal and transverse scanning planes. The best access was through the 9th/10th intercostal space at the junction with the anterior and middle axillary lines on the right and the posterior axillary line on the left.

Suprarenal mass and its differential diagnosis

Nine cases of suprarenal masses without endocrine abnormalities are presented: 2 adrenal pseudocysts, 2 adrenal myelolipomas, 2 neuroblastomas, 1 lymphoma metastatic to the adrenal glands, 1 teratoma, and 1 adrenal cortical carcinoma metastatic to the contralateral gland. The clinical and radiologic findings are discussed. Noninvasive and invasive procedures and their usefulness in diagnosing masses in the suprarenal area are reported. The importance of metastases to the adrenal glands in the differential diagnosis of suprarenal masses was investigated by reviewing the autopsies done from January through June, 1979, at The University of Texas System Cancer Center, M. D. Anderson Hospital and Tumor Institute, Houston, Texas. Adrenal metastases were found in 26 per cent of the cases studied. Breast and lung carcinomas and lymphomas were the most commonly found neoplasia. The relative incidence of microscopic and macroscopic metastases in all patients with tumor is discussed.

Sonographic features of gastrointestinal leiomyosarcoma

Five cases of gastrointestinal leiomyosarcoma were studied by ultrasound. Sonographic features of a huge mass with a thick echogenic rim and central sonolucent cavitation were seen in four cases with presenting symptoms of an abdominal mass. In a fifth case necrotic metastasis was seen in the liver after removal of a leiomyosarcoma. Although not pathognomonic, such features should strongly suggest the diagnosis of leiomyosarcoma.