OBJECTIVE: In childhood acute lymphoblastic leukemia (ALL), very promising results were obtained thanks to the developments in treatment strategies in recent years. However, acute complications during treatment continue to be the important causes of mortality and morbidity. In this study, acute complications that develop during the treatment of ALL in childhood were evaluated. METHODS: Medical records of 47 patients treated according to (ALL Intercontinental Berlin-Frankfurt-Munster) 2009 protocol between 2016 and 2021 were evaluated retrospectively. RESULTS: Of 47 patients, 28 (59.6%) were male and 19 (40.4%) were female. The mean age at diagnosis was 5.9 +/- 4.2 years. Forty-four patients (93.6%) were pre-B cell ALL, 3 patients (6.4%) were pre-T cell ALL. Of 47 patients, 9 (19.1%) were high risk, 32 (68.1%) were intermediate risk, and 6 (12.8%) were standard risk. Acute complications developed in 38 patients (80.8%). Among these complications, infectious complications are the most common and these were followed by gastrointestinal complications, drug-related reactions, thrombotic, neurological, and endocrine/metabolic complications, respectively. CONCLUSION: In terms of complications that may develop, the threshold of suspicion should be kept low, and patients should be treated with the same medical team in fully equipped centers with a multidisciplinary approach. Inpatient treatment strategies should be applied especially in the early stages of treatment. The importance of inpatient treatment strategy, especially in the early stages of treatment, is emphasized.

Background. Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare in children and adolescents. Standard management of these tumors has not been well established due to their rarity in this age group. We aimed to report the clinical and pathological characteristics of patients with this rare disease followed and treated between the years 1993-2022. Materials and methods. The medical records of patients with GEP-NETs were reviewed. Results. Fourteen patients (11 girls, 3 boys) were diagnosed with GEP-NET. The median age was 13 (9-18) years. Tumor localization was the appendix in 12, stomach in one and pancreas in one patient. Mesoappendix invasion was detected in four patients two of whom underwent right hemicolectomy (RHC) and lymph node dissection (LND). Of those, one patient had lymph node involvement. The other two had not further operations. Somatostatin was used in one with pancreatic metastatic disease and the other with gastric disease after surgery. No additional treatment was given in other patients. All patients are under follow-up without evidence of disease at a median follow-up of 85 months (7-226 months). Conclusion. GEP-NETs should be considered in the differential diagnosis of acute appendicitis and in cases with persistent abdominal pain. In children, there is invariably a favorable prognosis, and additional surgical interventions other than simple appendectomies generally do not provide benefits. Mesoappendix invasion may not necessitate RHC and LND.

Background: Optic pathway gliomas (OPG) are rare tumors in children. Lesion extent, visual functions, neurofibromatosis 1 (NF1), and age are factors that guide treatment. This study evaluates the clinical characteristics, treatment, and outcome of children and adolescents with OPG treated over a 31‐year period in a single center. Methods: Ninety‐five patients with OPG diagnosed between January 1990 and December 2021 were retrospectively evaluated. First‐line chemotherapy regimen consisted of vincristine and carboplatinum for 1 year. Radiotherapy was not used as first‐line treatment and tried to be avoided in the ones who progressed after first‐line treatment. Results: Ninety‐five children (44 male, 51 female) with a median age of 52 (1–216) months were evaluated. Sixty‐three (66.3%) had NF1 and 10 (10,5%) diencephalic syndrome. The most common presenting symptoms were visual abnormalities and/or proptosis, nistagmus, and behavioral changes. Twenty‐one (22.1%) patients with NF1 had stable disease throughout the follow‐up period and received no treatment. Sixty‐three of 74 patients received treatment at diagnosis and 11 due to progression during follow‐up. Only one adolescent received radiotherapy at progression. Patients who progressed, received further line systemic treatment (vinblastine; bevacizumab; vincristine–cisplatinum–etoposide). Ten‐year overall survival in all patients, in patients with NF1, and without NF1 were 97.2%, 98%, and 95.8% ( p > .05), respectively; 10‐year progression‐free survival (PFS) in all patients, in patients with NF1, and without NF1 were 71.6%, 85.7%, and 54.2% ( p = .001), respectively. Conclusions: In children with symptomatic/progressive OPG, chemotherapy consisting of vincristine–carboplatinum (VC) is effective. Radiotherapy may be avoided, especially in patients with NF1.

Background. Inflammatory myofibroblastic tumors (IMTs) are rare neoplasms in children. Traditionally, surgical resection has been the primary treatment modality with limited efficacy reported for conventional chemotherapy and radiation therapy. Recently, targeted therapies have emerged as potential options for selected cases. This study aimed to evaluate the demographic, clinical, laboratory, and radiological characteristics, as well as treatment outcomes, in children diagnosed with IMTs. Methods. This study involved a retrospective review of medical records for eight children diagnosed with IMTs between 1990 and 2022. We collected demographic, clinical, laboratory, and radiological data, as well as treatment outcomes. Data on tumor characteristics, surgical procedures, and chemotherapy or targeted therapy treatments were extracted. Results. The mean age at diagnosis was 9 years. None presented with metastatic disease at the time of diagnosis. Anaplastic lymphoma kinase (ALK) positivity was identified in tumor tissue from five patients. Among the six patients who underwent surgical resection, three achieved negative surgical margins. Of the three patients with positive surgical margins, one underwent re-resection, local and metastatic recurrences were noted in another, and one was started on crizotinib. A patient with an inoperable tumor at diagnosis was initiated on crizotinib and achieved complete remission. Ceritinib was administered to a patient with YWHAE-ROS fusion, resulting in more than 90% reduction in tumor volume. The median follow-up time was 67.5 months. The five-year overall survival and event-free survival rates for the cohort were 85.7% and 72.9%, respectively. Conclusions. While surgical resection remains the cornerstone of treatment for IMTs, favorable outcomes can be achieved with chemotherapy and targeted therapies in selected cases. Increasing the utilization of targeted therapies may be beneficial, particularly through molecular studies aimed at minimizing the side effects associated with conventional chemotherapy.

Objective: Childhood cancer survival rates have improved, but survivors face an increased risk of second malignant neoplasms (SMNs), particularly thyroid cancer. This study examines the demographic, clinical, genetic, and treatment characteristics of childhood cancer survivors who developed thyroid cancer as a second or third malignancy, emphasizing the importance of long-term surveillance. Methods: A retrospective review was conducted for childhood cancer survivors treated between 1990 and 2018 who later developed thyroid cancer as a second or third malignancy. Data on demographics, clinical characteristics, treatment, and outcomes were analyzed. Results: Among the 3204 childhood cancer survivors, 10 patients (6 female, 4 male) developed papillary thyroid carcinoma (PTC), a median of 9 years post-initial diagnosis. Radiation therapy, particularly to the head and neck, was commonly used. Genetic testing revealed mutations in the Cell Cycle CheckPoint Kinase 2 (CHEK2) and Adenomatous Polyposis Coli (APC) genes in four patients, possibly contributing to the increased risk. All were diagnosed through thyroid ultrasound and underwent total thyroidectomy, and three received radioactive iodine (RAI). No recurrences or deaths related to PTC occurred, with a median follow-up of 5.5 years after diagnosis. Conclusions: Radiation therapy, especially combined with chemotherapy, significantly increases the risk of thyroid cancer in childhood cancer survivors. Genetic predispositions also play a role. Lifelong thyroid cancer surveillance is essential, particularly for those who received radiation or chemotherapy. Further research is needed to refine surveillance strategies and better understand genetic factors that influence thyroid cancer risk. Early detection and ongoing monitoring are critical for improving long-term outcomes.