Myelolipoma

Myelolipome are rare benign tumors or tumor- like lesions composed of mature adipose tissue and hematopoietic tissue and variable amounts manifest mostly in the adrenal gland. The term was coined in 1929 by Myelolipom the French pathologist Charles Oberling ( 1895-1960 ).

Epidemiology

In autopsy studies Myelolipome were found at 0.08-0.4 % of cases. Men and women are equally affected. The peak age is in the 5th - 7th Decade of life.

Etiology

The causes of these Myelolipomen underlying are unknown. Discussed the possibility of metaplasia reticuloendothelial cells of blood capillaries as a result of stimuli, such as necrosis, infection or stress. Sometimes the tumor is seen as a place of extramedullary hematopoiesis. Recent studies show that both the fat as well as the myeloid component monoclonal origin, so that it may constitute a true neoplasia in the Myelolipom. In the literature, an association is described with congenital adrenal hyperplasia.

Pathology

Myelolipome are yellow to brownish, a few millimeters to 30 cm, circumscribed, but not encapsulated tumors. They occur usually solitary and unilaterally in the region of the adrenal gland to be rare but also bilateral and / or outside of the adrenal gland (eg in the retroperitoneum, mediastinum, liver, muscle fascia ) found.

Microscopically, the tumor consists of mature adipose tissue and myeloid cells together. Occasionally infarct areas, hemorrhage or bony metaplasia was observed.

Symptoms

The majority of Myelolipome are asymptomatic and are random, as found in the context of radiological examinations or autopsy. Only occasionally, especially for larger tumors, report the patients affected by abdominal or flank pain. Rarely there are endocrine disorders such as Cushing's, Conn's syndrome or congenital adrenal hyperplasia a.

Therapy

Small, asympatomatische Myelolipome require no therapy. Symptomatic tumors are treated by surgical removal of the adrenal gland.

Forecast

The prognosis of Myelolipomen is usually good. Malignant degeneration of the tumor has not been reported. As a rare complication may occur spontaneously or traumatically induced tumor rupture with the following hemorrhage. Data on mortality in Myelolipomen are not available due to the rarity of the lesion.

Swell

• Wegener: Whole body computed tomography. Blackwell Science, Berlin 1992, ISBN 3-89412-105- X
• Federle, Michael: Abdomen: The 100 top diagnoses. Urban & Fischer Verlag 2004: 319-321 ISBN 978-3-437-23590-0
• Goepel, M. et al.: Lipoma of the adrenal gland, case report and literature review. Urology 1998, 37: 526-539