Clinical and Pathologic Features Distinguishing Adrenocortical Tumors

 

Age of patient: Carcinomas show two peaks of occurrence: children less than 5 years of age and adults in 40s.

 

Capsular invasion:

(1) This is present in carcinomas, often with stromal reaction.

(2) This may not be useful since normal adrenal tissue is often adjacent.

 

Clinical syndrome in functional tumors:

(1) About half of adrenal cortical tumors are accompanied by hormonal manifestations.

(2) A large adrenal tumor >= 10 cm in diameter producing the adrenogenital syndrome in an adult tend to be a carcinoma.

(3) Tumors producing Cushing's syndrome without virilism tend to be adenomas, while Cushing's syndrome with virilism tend to be carcinomas.

(4) Aldosterone secreting tumors in adults tend to be adenomas.

(5) The presence of virilism alone tend to occur in carcinomas.

(6) The presence of feminization tends to occur in carcinomas.

 

Fibrous trabecular bands: Broad bands > 1 HPF wide are correlated with metastatic spread

 

Immunostaining: Immunostaining for EMA can separate adrenal cortical tumors from renal cell carcinomas but does not distinguish between cortical adenomas and carcinomas.

 

Laboratory Testing:

(1) Markedly elevated urinary 17-ketosteroids tends to occur in carcinomas.

(2) Negative clinical ACTH stimulation test tends to occur in carcinomas.

 

Metastases:

(1) Useful if present, but it may take years after initial surgery for these to appear.

 

Mitotic rate:

(1) A high mitotic rate is reliable for diagnosis of carcinoma but infrequent.

(2) The distribution of mitoses in carcinomas can be highly focal.

 

Nuclear pleomorphism: Useful if combined with other findings.

 

Systemic features (weight loss, fever): This is reliable for malignancy but infrequent.

 

Tumor necrosis:

(1) In carcinomas may be confluent, measuring 2 HPF or more in width.

(2) Adenomas do not show necrosis unless following venography.

 

Tumor weight:

(1) Carcinomas are often > 100 grams but can be smaller.

(2) The weights for small carcinomas and large adenomas can overlap.

 

Vascular invasion: This is reliable for malignancy but infrequent.