Hypernephroma are tumors that resemble the cortical portion of the adrenal gland. They probably arise from misplaced portions of adrenal tissue, and, as such "rests" consist of only cortical elements, these tumors do not resemble the medulla of the gland nor do they contain epinephrin. Are found most commonly in the upper pole of the kidney, liver, broad ligament, and in other abdominal tissues.

Although commonly benign and encapsulated, they may take on a malignant change, infiltrate, and give rise to metastases by means of the blood-vessels.

The cells are large and vesicular, with large round, centrally placed nuclei. The connective-tissue framework is very slight. Dilated capillaries and areas of hemorrhage are common.

Gliomas are growths composed of neuroglia or nervous connective tissue. As they arise from the epiblast, they cannot be classified with the mesoblastic tumors.

Are usually small, reddish in color, and not distinctly limited from surrounding tissues.

Microscopically they are composed of cells with large nuclei and with long fine processes.

Blood-vessels may be numerous and many areas of hemorrhage present.

Are benign and slow growing.