Only a minority of patients with brain germinomas will develop a recurrence. This is likely to happen in patients who have received irradiation to the tumor site only (with or without chemotherapy) or, for whatever reason, have received chemotherapy only. Such patients can be virtually uniformly cured by appropriate radiation therapy. However, for those patients who have already received focal irradiation, the toxicities of the added irradiation are not minor, and must be considered carefully. For children who do develop recurrence of tumor despite prior irradiation and chemotherapy, an approach incorporating very high dose (marrow destructive) chemotherapy and blood cell rescue has been shown to be associated with 80% cure rates. The treatment of children with recurrence of mixed malignant germ cell tumors depends upon the predominant cell type at recurrence. If germinoma, then treatment should be as indicated above for pure germinomas. If teratoma, then surgical resection will be the crucial form of treatment. If the more malignant GCT elements predominate (eg. yolk sac tumor, choriocarcinoma, embryonal carcinoma) then one has a much tougher battle ahead. The best approach employs two stages; the first, use of chemotherapy to achieve a state of minimal residual tumor; the second stage, the use of marrow ablative chemotherapy with blood cell rescue as indicated above for pure germinomas. This approach has resulted in about 50% cure rates for children with recurrent mixed malignant germ cell tumors of the brain. A critical component here is the ability to achieve a state of minimal residual tumor with further chemotherapy. It is imperative that new drugs and drug combinations be identified that will have the best chance of achieving such tumor responses. One approach that a number of institutions in North America are considering as a pilot is the combination of gemcitabine, paclitaxel and oxaliplatin –drugs that have been shown effective in recurrent germ cell tumors arising outside the brain in adults. |