No abstract

The incidence of esthesioneuroblastoma in children under 15 years of age is 0.1 per 100.000 children. Distinctive histological features of this tumor are diffuse accumulation of neuron-specific enolase, synaptophysin, chromogranin, and variable expression of cytokeratins. Diagnosis of the tumor includes endoscopic examination of the nasal cavity and nasopharynx, magnetic resonance imaging (MRI) and computed tomography (CT) of the skull base, paranasal sinuses with intravenous contrast. PET-CT is advisable to use for the detection of regional and distant metastases, as well as for suspected relapse. In patients of adult age, a negative effect on the outcome of the disease was detected, the detection of metastases in the lymph nodes of the neck, the presence of tumor cells at the edges of tumor resection and a high degree of malignancy of the tumor according to the Hyams system. Therapeutic approaches depend on the stage of esthesioneuroblastoma by Kadish. In the A-stage, surgical treatment is advisable. In the presence of tumor cells at the edges of the resection or residual tumor, radiation therapy is performed. In case of B-stage, surgical treatment is combined with the mandatory irradiation of the primary tumor area. In patients with the C-stage, neoadjuvant chemotherapy or radiation is performed, followed by a surgical treatment, adjuvant chemotherapy and/or radiation therapy. Patients with D-stage chemoradiation therapy is indicated. There is no consensus on an effective drug regimen. Overall 5-year survival varies significantly depending on the design of the study — 55% to 98%. Further study of the features of the clinical picture, morphological and molecular features and the course of the disease will help to improve our understanding of the nature of the tumor.

Российский журнал ДЕТСКОЙ ГЕМАТОЛОГИИ и ОНКОЛОГИИ R u s s i a n J o u r n a l o f P e d i a t r i c H e m a t o l o g y а n d O n c o l o g y 83 К л и н и ч е с к и е н а б л ю д е н и я || C l i n i c a l c a s e s

Undifferentiated nasopharyngeal carcinoma (UNC) differs from other epithelial tumors of the head and neck by a close connection with lymphatic tissue, epidemiology, and biological characteristics that determine the clinical course of the disease and therapeutic approaches. In this histological variant, a high titer of antibodies to the Epstein–Barr virus (EBV) was observed in blood of 100% of patients. Absence of specific symptoms, polymorphic clinical picture, and latent disease course lead to the detection of a tumor in children only at stages III–IV. Radiotherapy (RT), as the only method for the treatment of UNC, has been used for almost 30 years in all age groups of patients regardless of the disease stage. In most studies, 1.8–2 Gy per day and 50–70 Gy per course were applied to irradiate the nasopharynx and the affected lymph nodes. Modern treatment protocols require the use of conformal irradiation using magnetic resonance imaging (MRI) and computer tomography (CT) with contrast enhancement to form a three-dimensional model of RT planning. High efficacy and a radiosensitive effect were observed when platinum-based antineoplastic drugs were administered. The chemotherapy (CTx) regimens for pediatric patients included cisplatin, cyclophosphamide, and methotrexat which were administered both before and after RT. Maintenance therapy with interferon-β also positively affected the treatment results. Combined approaches allowed to increase the level of five-year overall survival rate up to 70–90%. The analysis of complications and long-term treatment effects in children with UNC showed a significant effect of total focal dose and irradiation technique on early radiation reactions from local tissues in the form of dermatitis, mucositis, and xerostomia, as well as on delayed radiation complications and development of second tumors. The review demonstrates the main therapeutic approaches to the treatment of children with UNC both in the historical aspect and according to current trends.