Clinical features and treatment results in children with head and neck rhabdomyosarcoma

Objective: It was aimed to investigate the clinical features and treatment outcomes in children with head and neck rhabdomyosarcomas. Patients and methods: The clinical features, tumor location, histopathological diagnosis, stages, treatment and outcomes of 65 children with head and neck rhabdomyosarcoma diagnosed and treated between 2004-2018 in Hacettepe University Faculty of Medicine, Department of Pediatric Oncology were retrospectively analyzed. Results: The median age of 65 patients was 5.8 years (2.8 months - 15.2 years; M/F: 37/28). The primary tumor localization was parameningeal in 49.2% (n=32), 35.4% orbital (n=23), and 15.4% other non-parameningeal (n=10) locations. The patients most frequently presented with the complaint of swelling/mass (81.5%). Surgery was performed in 12.3% (n=8) of the patients with total resection or microscopic residue; 87.7% (n=57) had postoperative gross tumor mass (partial resection in 18 patients, biopsy in 39 patients). Partial resection was performed in only six patients with the parameningeal location, while gross or partial resection was performed in 16 patients with the orbital location. Histopathologically, embryonal subtype was 73.8% (n=48), alveolar subtype 13.7% (n=9), spindle cell/sclerosing subtype 4.6% (n=3). Subtypes were unknown in five patients. According to the TNM staging, 44.6% (n=29) of the patients had stage I; 7.7% (n=5) stage II; 32.3% (n=21) stage III; 15.4% (n=10) stage IV diseae. According to the COG (The Children's Oncology Group) risk stratification, 38.5% (n=25) of the patients were in the low risk group; 44.6% (n=29) in the intermediate risk, 16.9% (n=11) in the high risk group. All patients were treated with systemic chemotherapy as determined according to risk groups. Five-year event-free and overall survival rates were 41.5% and 58.5% in those receiving CDCV (cisplatin, doxorubicin, cyclophosphamide, vincristine) chemotherapy; VAC-VAdrC (VAC: vincristine, actinomycin-D, cyclophosphamide; VAdrC: vincristine, doxorubicin, cyclophosphamide), 58.2% and 90.9% were found. Four of the five patients who received the PIAV (ifosfamide, cisplatin, vincristine, doxorubicin) protocol died, and fifth patient was alive; three of six patients who received VDC/IE (vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide) died, three were alive. The five-year event-free survival rate of 65 patients with head and neck rhabdomyosarcoma was 41.2%, and the overall survival rate was 59.3%. Tumor location, stage, and risk group were found to be important in survival analysis. Fiveyear overall survival rate in the orbital location was 85.2%, in the other nonparameningeal location 80%, and in the parameningeal location 34.2% (p=0.01). The five-year overall survival rate was 80.3% in the early stages (stage I and II), 36.6% in the advanced stages (stage III and IV) (p<0.001). The five-year overall survival rate of low-risk patients was 82.4%, 57.3% of intermediate-risk patients, and 18.2% of highrisk patients (p<0.001). 10 of 11 patients in the high risk group died. Relapse was observed in 13 (30.2%) of 43 patients whose treatment response was complete or partial. 10 of the 13 patients with relapses died. Conclusion: Early diagnosis and local control of the disease are critical in patients with head and neck rhabdomyosarcoma. The prognosis is poor in parameningeal localization, should be improved with appropriate surgery, radiotherapy and intensive chemotherapy. New innovative treatment approaches should be investigated to improve the outcomes in advanced stage, parameningeal, refractory/relapsed diseases.