Tumor regression patterns by follow-up duration in patients with nasopharyngeal carcinoma treated with concurrent chemoradiotherapy

The aim of this study was to describe the patterns of tumor regression with respect to follow-up duration after chemoradiotherapy in patients with nasopharyngeal carcinoma. a total of 27 patients with nasopharyngeal carcinoma were included and received definitive concurrent chemoradiotherapy. patterns of primary tumor regression and development of locoregional recurrences were evaluated by imaging studies every 1 to 2 months. primary tumors gradually regressed over the period of follow-up. the median time to full regression was 4.9 months (range,1.5-19.4). in 61.5% of patients,the primary tumor continued to regress for >4 months after completion of chemoradiotherapy. six patients experienced locoregional recurrence during follow-up,all of which occurred after full regression of the primary tumor. a patient group with delayed regression did not have poorer prognosis than a patient group with early regression. older age,non-current-smoker status,advanced t stage,and higher daily radiation dose were significantly associated with delayed primary tumor regression. nasopharyngeal carcinoma continued to regress for >4 months after chemoradiotherapy in a considerable number of patients. we recommend waiting for >4 months for full regression of nasopharyngeal carcinomas after chemoradiotherapy,if signs of persistent or recurrent disease are not evident on follow-up examination. © the author 2016.