High dose chemotherapy with autologous bone marrow rescue for children with diffuse pontine brain stem tumors

Purpose. Diffuse pontine tumors are highly lethal, and there are few long-term survivors with the standard treatment of external beam irradiation. We investigated the effectiveness of high-dose thiotepa and etoposide-based chemotherapy regimens with autologous bone marrow rescue (ABMR) in children with pontine tumors. Patients and methods. Sixteen children with diffuse pontine tumors were treated. Ten had resistant or recurrent tumors. All ten had previously received irradiation; five had also received chemotherapy and one, beta-interferon. Three high-dose chemotherapy regimens were employed. Six patients received three days of thiotepa (300 mg/m²/day) and etoposide (250-500 mg/m²/day) (TE); two received three days of carmustine (BCNU) (200 mg/m²/day divided every 12 hours) followed by TE (BTE); and two received three days of carboplatin (500 mg/m²/day) followed by TE (CTE). Six other patients had newly-diagnosed tumors and had not received any prior treatment. They all received the BTE regimen and subsequently were treated with hyperfractionated irradiation (7200-7800 cGy) beginning approximately six weeks post-ABMR. Results. There were two toxic deaths (13%), both in previously treated patients, due to multiorgan system failure and Candida septicemia in one case each. Median survival of the patients with resistant or recurrent disease was 4.7 months (range 0.1-18.7) from time of ABMR. Median survival of the newly-diagnosed patients was 11.4 months (range 7.6-17.1) from the time of ABMR. Conclusion. High-dose chemotherapy utilizing these regimens followed by ABMR did not appear to prolong survival compared to conventional therapy in these children with pontine tumors. Alternative strategies need to be developed for this highly lethal disease.