The routes of spread are:
- Local
- Infiltration and spread along tissue planes - sometimes for great distances.
- Regional lymphatics
- Overall 5% incidence of metastatic disease to lymph nodes in all sites except:
- Paratesticular: 40%
- Genitourinary: about 20%
- Extremity: 15 - 20%
- Orbit: almost 0%.
- Overall 5% incidence of metastatic disease to lymph nodes in all sites except:
- Hematogenous
- To distant sites such as lung, bone and bone marrow (occurs in about 10-20% of patients at presentation).
- The primaries are usually in the extremities, trunk or retroperitoneum.
- Bone metastases are often seen in the small bones of the hands and feet.
- Leptomeningeal
- Parameningeal tumors can be associated with meningeal thickening and spread via CSF pathways.
CSF Cytology: Below are small round blue tumor cells found in the CSF of a patient with leptomeningeal disease from rhabdomyosarcoma.
