Postoperative neoadjuvant chemotherapy before radiotherapy as compared to immediate radiotherapy followed by maintenance chemotherapy in the treatment of medulloblastoma in childhood: results of the German prospective randomized trial HIT’91. - Kortmann,RD.; Kuhl,J.; Timmermann,B.; Mittler,U.; Urban,C.; Budach,V.; Richter,E.; Willich,N.; Flentje,M.; Berthold,F.; Slavc,I.; Wolff,J.; et al. (Int J Radiat Oncol Biol Phys, 2000)