Peripheral primitive neuroectodermal tumor: Challenge for multimodal treatment

The primitive neuroectodermal tumor (PNET) is an extremely aggressive soft tissue neoplasm that occurs in children and adolescents. We retrospectively reviewed our therapeutic experience with a multidisciplinary approach, com bining surgery, chemotherapy, and radiation therapy. Treatment of PNET was carried out in compliance with the soft tissue protocol (CWS) from the Germ an Society of Pediatric Oncology. Biopsy-proven diagnosis was followed by c hemotherapy, which in all cases led to partial remission, allowing excision of the remainder of the tumor without mutilation. After excision, irradiat ion of the tumor site and two further sequences of chemotherapy were perfor med. When PNET of the paravertebral region caused symptoms of paralysis and immediate surgery was required, postoperative chemotherapy, a second-look operation, and irradiation were undertaken. Between 1986 and 1998 we treate d 13 patients (median age 15 years). In five patients the PNET originated f rom the chest wall and in eight patients from the paravertebral and retrope ritoneal region. Five patients died after 20 months on average, and the rem aining eight patients are in full remission after 7, 16, 46, 55, 70, 74, 75 , and 115 months, respectively. Close cooperation between surgeons and thei r pediatric and radiotherapy colleagues is obligatory when treating PNET. C hemotherapy as the first stage is mandatory to avoid a mutilating surgical procedure and intraoperative tumor cell dissemination.