To stage germ cell tumors need:
- Gadolinium enhanced MRI of the craniospinal axis
- CSF cytology
- Tumour markers in blood and CSF
No generally accepted staging system currently in use for germ cell tumors.
- Most investigators use the M scale, or Chang staging system, that was devised for staging medulloblastoma.
- T-stage evaluation, a measure of the size of the tumor, is not usually used for germ cell tumors. This is primarily due to their midline location.
Chang staging system for medulloblastoma:
M0 |
No evidence of subarachnoid or hematogenous metastasis |
M1 |
Tumor cells found in cerebrospinal fluid |
M2 |
Intracranial tumor beyond primary site |
M3 |
Gross nodular seeding in spinal subarachnoid space |
M4 |
Metastasis outside the cerebrospinal axis (especially to bone marrow, bone) |
(Source: Pediatric Radiation Oncology; Halperin, Constine, Tarbell, Kun)
- Germ cell tumors are commonly found in the M1 stage upon diagnosis.
- CSF cytology is often positive.
