PROGNOSTIC FACTORS AND FAILURE PATTERNS IN NON METASTATIC NASOPHARYNGEAL CARCINOMA AFTER VOLUMETRIC MODULATED ARC THERAPY, A RETROSPECTIVE STUDY

Purpose : The aim of this study was to identify the key failure patterns and prognostic factors of relapsed Nasopharyngeal carcinoma (NPC). Patients and Methods : Between January 2013 and December 2017, so during 5 years, a total of 101 patients with NPC were diagnosed and treated with radiotherapy (RT) or concurrent chemo radiotherapy at Military Teaching Hospital Mohamed V (MTHM V) of Rabat, Morocco. The sex ratio was 2,6 and the median age was 42,95?16,362 years. Regarding anatomo-pathological aspect, the undifferentiated carcinoma has been the most frequently, noticed in 93,1 %. The treatment received was based on neoadjuvant chemotherapy followed by concomitant chemo radiotherapy (RCC) in 79,2 % of patients, a RCC from the outset in 12,8 % of cases, and a neoadjuvant chemotherapy followed by radiotherapy in 8 % of cases. All patients were treated with VMAT technique with a prescribed doses levels of 69.96, 59.4 and 54 Gray in 33 sessions. Results : There were just 3 patients with incomplete follow-up, but complete follow-up information was available for 98 patients with a median follow-up time of 45,37 ? 17,31 months. The overall survival (OS) and the relapse free survival (RFS) rate after 5 years was 82,3 % and 76,8% respectively. Among the 101 patients, 21 (20,8 %) relapsed with the time to relapse was 22,6 ? 10,3 months. The loco regional relapse founded in 5 patients (5%) and metastases to the distant organ were found at 16 patients (15,8 %). Overall survival after 4 years of relapse changes according to seat of relapse. There OS at 4 years for locoregional relapse and for distant metastases was estimated at 83% and 7,3% respectively. Conclusion : This report reviews NPC recurrence data after primary treatment. Rates of local and distant relapse were comparable with those previously reported and the majority of recurrences occurred within the first five years. The prognosis after relapse varied with nodal status, seat of relapse as well as the remission duration after treatment.