asco@alo33:162199 JSONTXT

Background: Nasopharyngeal carcinoma NPC is a central tumor ith rich lymphatic netork and a propensity for bilateral cervical lymph node metastasis. There is an orderly pattern of lymph node involvement in NPC as opposed to other head and neck squamous cell carcinoma here skip metastasis is present. These lymph nodes are prophylactically irradiated even in node negative disease. Hoever, there is no current standard for prophylactic neck irradiation in node negative or limited retropharyngeal node RP positive NPC. Limiting radiation to the upper neck spares loer neck soft tissues and thyroid gland. The aim of this paper is to synthesize the current evidence regarding effectiveness of upper neck irradiation UNI versus hole neck irradiation WNI as prophylactic neck irradiation in node negative or limited RP node positive NPC. Methods: Search of relevant articles ere done from 2000 to October 2015. Critical appraisal and meta-analysis of the eligible studies ere undertaken to assess the effectiveness of UNI versus WNI as prophylactic neck irradiation in node negative or limited involved retropharyngeal node NPC. Results: One randomized controlled trial and 4 retrospective cohorts ere included in this meta-analysis. Only one randomized controlled trial investigated on the use of prophylactic UNI versus WNI and shoed no confirmed nodal relapse in both arms. Pooled analysis of four retrospective studies shoed an odds ratio of 1.68 CI- 0.64- 4.40 in nodal recurrence, hether in-field or out-of-field recurrence. There as no significant difference on the rate of nodal recurrence hen UNI versus WNI as prophylactic node irradiation as used for node negative or limited RP positive NPC. Pooled data from three studies shoed no significant difference in 5-year distant metastasis and overall survival beteen UNI and WNI ith an odds ratio of 1.09 0.58-2.03 and 0.99 O.60-1.63 respectively. Conclusions: In node negative or limited RP positive NPC, it may be a reasonable option to treat only the upper neck levels II, III and VA ithout compromising nodal control, distant metastasis and overall survival.,J Clin Oncol 34, 2016 suppl; abstr 6069 00:00.0,Head and Neck Cancer