Rhabdomyoma

Rhabdomyoma is a rare, completely benign tumor. It is a variant of rhabdomyosarcoma, which is malignant. Both tumors originate from the mesenchyme, specifically from striated skeletal muscle. This tumor was described by Jaroslav Hlava for the first time – most famous Czech pathologist, the first professor of pathology at the newly established Czech Medical Faculty in Prague.

Division
The tumor can appear both prenatally and postnatally. 2 forms are distinguished based on onset:


 * adult;
 * fetal.

According to the location of the tumor, 2 types are distinguished:


 * cardiac (in the heart), it may manifest in association with tuberous sclerosis or unrelated to it;
 * extra cardiac (soft tissue), head, neck.

Macroscopy
The tumor commonly occurs in children up to 1 year of age. Macroscopically  it presents as multiple light nodes in the myocardium, which protrude into the heart chambers.

Microscopy
In the microscope we can see large cells with abundant cytoplasm filled with vacuoles of glycogen, in between the vacuoles there are thin cytoplasm strips filling out the space between the nucleus and the cell membrane – the so called spider cells/spider-like cells. In addition we can detect actin and desmin in the neoplastic cells, this is a proof of these cells being derived from muscle cells.

Prognosis
Depends on the extent of the disease. If the child survives, the nodes regress over time.

Related articles

 * Mesenchymal tumors
 * Cardiac tumors
 * Rhabdomyosarkoma