Asia-Pacifc Journal of Clinical Oncology 2016; 12: 143–150 doi: 10.1111/ajco.12460 ORIGINAL ARTICLE Does primary tumor volume predict the outcome of pediatric nasopharyngeal carcinoma?: A prospective single-arm study using neoadjuvant chemotherapy and concomitant chemotherapy with intensity modulated radiotherapy Mohamed S. ZAGHLOUL, 1 Eman ELDEBAWY, 1 Soha AHMED, 1 Hany AMMAR, 1 Ehab KHALIL, 1 Hany ABDELRAHMAN, 2 Wael ZEKRI, 2 Hosam ELZOMOR, 2 Hala TAHA 3 and Amr ELNASHAR 4 1 Radiation Oncology Departments, 2 Pediatric Oncology Departments, 3 Pathology Departments, and 4 Research Departments, Children’s Cancer Hospital, Egypt and National Cancer Institute, Cairo University, Cairo, Egypt Abstract Background: Nasopharyngeal carcinoma is rare in children and adolescents; however, it has a better prog- nosis than in adults. Nevertheless, its prognostic factors are not clearly documented. Patients and methods: A prospective single-arm study was performed in 32 nonmetastatic Stages II–IV nasopharyngeal carcinoma (NPC) patients, below age 18 years. The treatment regimen included three courses of neoadjuvant chemotherapy (cisplatin and fuorouracil) followed by concomitant chemoradiotherapy (simultaneous integrated boost-intensity modulated radiotherapy [SIB-IMRT] with three cycles of cisplatin). Results: All patients completed their prescribed treatment with tolerable acute side-effects. The 3-year overall (OS), event-free (EFS), local recurrence-free (LRFS), and distant metastasis-free (DMFS) survival rates were 83 ± 8, 77 ± 8, 92 ± 6 and 77 ± 9 percent, respectively. Although the median initial (pretreatment) gross tumor volume of the primary site (GTVp) increased with increasing stage, yet these differences did not rank to the level of signifcance. However, GTVp (with a cut-off value of 54.5 mL) was the only signifcant prognostic factor determining OS, EFS, LRFS and DMFS. On the other hand, age, gen- der, T stage, AJCC stage and footprint histopathological EBV did not have statistical signifcant impact on any survival rate. The late toxicity of this regimen was much lower than that reported with the conformal treatment. Conclusion: Neoadjuvant chemotherapy and concomitant chemo-radiotherapy using SIB-IMRT led to excellent outcome with reduced late toxicity in juvenile nasopharyngeal carcinoma. GTVp is the sole prog- nostic factor that showed statistical impact on survival rates when applying this regimen. Key words: chemo-radiotherapy, concomitant, nasopharyngeal carcinoma, neoadjuvant, pediatric and adolescents, prognostic factors Correspondence: Mohamed S. Zaghloul, MD, Children’s Cancer Hospital, Egypt & National Cancer Institute, Cairo University, 1 Sekket El Emmam, Sayeda Zainab, Egypt. Email: mszagh@yahoo.com Confict of interest: none Accepted for publication 6 January 2016. INTRODUCTION Nasopharyngeal carcinoma (NPC) is a rare disease in children, accounting for less than 5 percent of all pediatric cancers. 1 NPC in childhood differs from the adult form by its close association with Epstein–Barr virus (EBV) infec- tion, a higher rate of undifferentiated histopathology and a greater percentage of advanced loco-regional disease. 2 C  2016 John Wiley & Sons Australia, Ltd