PTCT-01: INTERCONTINENTAL MULTIDISCIPLINARY DATA COLLECTION AND TREATMENT OPTIMIZATION STUDY FOR PATIENTS WITH CHOROID PLEXUS TUMORS

BACKGROUND: Choroid plexus tumors (CPTs) are rare pediatric tumors. They are classified by the World Health Organization as Choroid plexus papillomas (CPP), Atypical choroid plexus papillomas (APP) and Choroid plexus carcinomas (CPC). Current recommendations for the treatment of CPTs include surgical resection followed by adjuvant chemotherapy and or radiation therapy. The CPT-SIOP 2009 protocol compared four different chemotherapy treatment arms (standard arm A-Cyclophosphamide/VP16/VCR (CycEV) alternating with Carboplatin/VP16/VCR CarbEV) blocks, arm B-Doxorubicin/Cisplatinum/Actinomycin-D/VCR, arm C-high dose Methotrexate and arm D-Temozolomide/Irinotecan). The study closed due to insufficient enrollment of formally randomized patients. Our study reviews the patient data registry, which includes non-randomized patients. METHODS: Clinical course was evaluated amongst patients enrolled in the CPT-SIOP 2009 protocol. Data was obtained from international institutions including Australia, New Zealand, Germany, Lebanon, Turkey, Switzerland and USA. Qualitative parameters included age, sex, presenting symptoms and adjuvant therapy. Overall survival and event free survival were analyzed. RESULTS: We identified 27 cases with CPTs (APP 5, CPP 5, CPC 17), 9 females and 15 males, (2 unknown). The mean age at presentation was 7 years with a median age of 2.4 years (range 0.16 to 58 years). Twelve patients were treated under arm A, (1 B, 4 C, 1 D, 3 in observation and 6 unknown). 2y overall survival/2y EFS for n = 12 CPC patients on arm A was 78%/ 35% with a median follow up of 1.7 years, compared to 76%/ 63% for n = 41 CPC patients treated with non-alternating blocks of CarbEV or CycEV in the SIOP-CPT database. CONCLUSION: The outcome of alternating CarbEV/CycEV appears inferior to non-alternating cycles of either CarbEV or CycEV and is no longer recommended as a guidance in the SIOP-CPT registry. Our aim is to continue following these patients over time to monitor overall and event free survival.