These tumors are not as radiosensitive and it is difficult to justify RT dose reductions.
Craniospinal RT is much less controversial and usually regarded as necessary.
The RT dose is similar to that used for the treatment of medulloblastoma.
Adjuvant chemotherapy is standard therapy.
NGGCTs (also called Non-Seminomatous Germ Cell tumors or NSGCTs) consist of several histologies:
- Embryonal carcinoma
- Endodermal sinus tumor (yolk sac tumor)
- Malignant teratoma
- Mixed tumors
- Tumors may include one or more of these histologies and sometimes contain germinomatous elements.
- These tumors are not as radiosensitive as pure germinomas and their prognosis following standard radiotherapy alone is poor (20-45% five-year survival).
The COG ACNS0122 protocol used chemotherapy and craniospinal RT to improve survival for NSGCTs:
- Three-drug induction chemotherapy regimen with carboplatin, VP-16, ifosfamide - followed by craniospinal RT and an involved field boost RT.
- This protocol called for 36 Gy in 180 cGy fractions to the craniospinal axis followed by a boost treatment to total dose of 54 Gy to the primary tumor for non-metastatic disease.
- If a patient did not obtain a complete response after neoadjuvant chemotherapy second-look surgery was recommended.
- For patients with persistent positive markers, residual malignant elements as assessed histologically, or residual unresectable disease, an attempt to increase survival was made by using myeloablative chemotherapy with peripheral bone marrow stem cell rescue before the craniospinal RT.
Accrual to this study is now completed.