QOS-19: NECESSITY OF TREATMENT SPARING IN CHILDREN WITH CENTRAL NERVOUS SYSTEM (CNS) TUMOURS AND INTELLECTUAL DISABILITIES (ID): IS THIS THE CASE?

The incidence of CNS-tumours in children with ID is poorly documented, but as they are living longer, chances of developing cancer also increase. Between 1999-2016 we treated 16 patients having ID. Neurofibromatosis(1/2) were excluded. 10/16 were males, median-age 4 years, having: medulloblastoma(7), ependymoma(2), low-grade-glioma(1), high-grade-glioma(2), AT/RT(1), PNET(1), germ-cell-tumor(1), glioneuronal-tumour(1). Their ID/related syndromes were: autism-spectrum disorder(1), mithocondrial encephalopathy(1), multiple chromosomal-anomalies(1), CHARGE-syndrome(1), Klinefelter-syndrome(1), post-partum-asphyxia(1), tuberous-sclerosis(1), corpus-callosum-agenesia(1), mental retardation ± dysmorphisms(8). For 4 patients the presence of ID and cancer led to perform genetic-tests with diagnosis of Gorlin-syndrome into two cases. Four patients experienced a diagnosis delay probably correlated to ID. “Treatment sparing” to reduce toxicity was pursued in five patients: a 4 years-old with post-partum asphyxia/medulloblastoma didn't receive radiotherapy, after induction chemotherapy, substituted by high-dose chemotherapy; radiotherapy was delivered at relapse and he died 42 months after relapse. The second child with Charge-syndrome/ anaplastic-metastatic-medulloblastoma received reduced total dose Thiotepa to prevent severe mucositis; he died 19 months after diagnosis with only supportive-care at relapse. Three children with medulloblastoma/PNET received only palliative oral CT at relapse. Four children (5.6 years, mean) performed RT with sedation for inadequate compliance. For the 16 children, 5-year OS/EFS were 64%/51% respectively at median-follow-up of 62 months. We did adopt treatment sparing only in severe disabilities, while in most cases a “treatment adaptation” was made; OS seems to be similar to the other children without ID. A role of ID and genetic correlation with cancer is emerging, this results in a variety of crucial issues.