Solid Malignant Tumors in Infancy: A Single-Center Experience.

Infantile tumors are rare and different from those in older children in terms of anatomic site, histologic features, and behavior. Thus, they require adapted multimodality approaches for diagnosis and treatment. We aimed to evaluate the characteristics and outcomes of different tumor types in children under 1 year of age who were referred to the Hacettepe University Pediatric Oncology Department over 20 years. There were 515 infants, with a mean age of 6.1±3.4 months, diagnosed with malignant tumors. The male/female ratio was 1.15. Thirty-three (6.4%) of them were diagnosed in the newborn period. Prenatal diagnosis was made in 4.9% of the patients. The most common finding was a mass and symptoms related to the mass (81.6%). The mean time to diagnosis was 31.3±44.7 days. The most common histopathologic diagnoses were retinoblastomas (33.6%), neuroblastomas (27.1%), renal tumors (10.3%), and central nervous system (CNS) tumors (9.7%). Forty patients (7.8%) had congenital anomalies, genetic syndromes and diseases, and metabolic and immune deficiency disorders. Multimodal treatment was administered according to diagnosis, stage, and risk group. The 5-year overall survival (OS) was 86.6% in the whole group and 83.4% in newborns. The best 5-year OS (>91.5%) was observed for renal tumors, retinoblastomas, and neuroblastomas. Conversely, the lowest OS was observed for CNS tumors (52.5%). Our results contribute to a better understanding of the characteristics and outcomes of the tumors in this age group.