MON-096 Endocrine Complications Following Cancer Treatment in Survivors of Pediatric Solid Tumors: 18 Years’ Experience of a Single Academic Center

Background: Survival rates of pediatric cancer have been significantly improved over recent decades because of advances in chemotherapy and radiotherapy. The endocrine consequences of cancer treatment have become the major medical issues in the childhood cancer survivors. This study was performed to investigate the long-term endocrine complications in survivors of pediatric solid tumors. Methods: From 2000 to 2018, 402 patients were diagnosed with solid tumors including hepatoblastoma (n = 72), neuroblastoma (n = 117), Wilms tumor (n = 57), Ewing sarcoma (n = 40), osteosarcoma (n = 65), and rhabdomyosarcoma (n = 51) in our institute. Among them, 96 patients (24%) were expired during the follow-up period. Growth profiles and endocrinologic findings were analyzed by retrospective chart review in 306 survivors of solid tumors. Results: The median age at diagnosis of primary cancer was 3 years (range, 0 month to 18 years). The mean treatment duration was 11.7 ± 12.6 months, and the mean follow-up duration after cancer treatment was 7.1 ± 4.8 years. Short stature,which was defined by height-SDS below -2.0, was found in 39 patients (12.7%) with the mean height-SDS of -2.59 ± 0.45. Primary hypothyroidism was detected in 19 patients (6.2%), and 15 of them were treated with radiotherapy or (131)I-MIBG therapy due to the metastatic neuroblastoma. Sixteen patients (5.2%) developed hypergonadotropic hypogonadism, whereas three patients (1%) were diagnosed with central precocious puberty. Vitamin D deficiency and osteoporosis were found in 4 patients (1.3%) and 3 patients (1%), respectively. Primary adrenal insufficiency was found in one patient who underwent bilateral adrenalectomy because of bilateral neuroblastoma. One patient with rhabdomyosarcoma in the nasal cavity underwent high dose radiotherapy (50.4 Gy) around the tumor site, eventually leading to multiple pituitary hormone deficiency. In multivariable analysis, longer duration of treatment (≥24 months) was associated with the endocrine complications (OR = 3.94; CI 1.41-11.06) and hematopoietic stem cell transplantation was a major risk factor for endocrine complications (OR = 4.70; CI 2.14-10.29). Conclusions: Various endocrine complications can occur in survivors of solid tumors in children and adolescents caused by treatment modalities including surgery, chemotherapy, and radiotherapy, rather than the tumor itself. Lifetime monitoring is necessary to detect endocrine consequences such as growth retardation, hypergonadotropic hypogonadism, and thyroid dysfunctions.