A prospective clinical study with long-term follow-up of the correlation between dynamic contrast-enhanced magnetic resonance parameters and prognosis in patients with locally advanced nasopharyngeal carcinoma / 中华放射医学与防护杂志

ABSTRACT

Objective:To explore the relationship between semi-quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and long-term prognosis of locally advanced nasopharyngeal carcinoma, and to find prognostic indicators from non-invasive images of locally advanced nasopharyngeal carcinoma.Methods:Data were collected from January 2011 to January 2012 via a prospective clinical trial with locally advanced nasopharyngeal carcinoma. Clinical information was from 71 patients who completed the treatment plan with long-term follow-ups and UICC 2010 stage Ⅲ, Ⅳ A, Ⅳ B. The patients received three cycles of Taxotere-Platinol-Fluorouracil (TPF) regimen chrono-chemotherapy, followed by two cycles of concurrent paclitaxel chemotherapy with intensity-modulated radiotherapy (IMRT). DCE-MRI examination was performed before induction chemotherapy to obtain DCE-MRI related semi-quantitative parameters. Correlation analysis was conducted between DCE-MRI related semi-quantitative parameters and short-term efficacy of nasopharyngeal lesions after concurrent radiotherapy and chemotherapy. Results:Of all 77 patients, 71 completed treatment and were followed up from 9 to 86 months, with a median follow-up of 77 months, with 80.2% and 67.6% in 3- and 5-year OS, 73.2% and 60.5% in 3- and 5-year PFS, respectively. Evaluation of short-term efficacy of nasopharyngeal lesions after concurrent chemoradiotherapy the difference in tissue arrival time of contrast agent between complete response (CR) group and partial response (PR) group was statistically significant ( t=0.537, P<0.05). Univariate survival analysis found that OS ( χ2=3.982, P<0.05) and PFS ( χ2=4.019, P<0.05) in the group with short contrast arrival time were significantly higher than those in the group with long contrast arrival time. OS ( χ2=7.593, P<0.05) and PFS ( χ2=5.624, P<0.05) of patients aged over 45 years were significantly lower than those aged less than 45 years. Cox multivariate regression model showed that advanced clinical stage (stage Ⅳ A, Ⅳ B) ( P=0.048) and age≥45 years ( P=0.031) were independent prognostic factors of OS in patients with nasopharyngeal carcinoma. Long arrival time of contrast agent ( P=0.018), age≥45 years ( P=0.004), advanced N(2-3) stage ( P=0.032) and enhancement peak<3 000 ( P=0.005) were independent prognostic factors of PFS in patients with nasopharyngeal carcinoma. Conclusions:The arrival time of the contrast agent in DCE-MRI may be a reliable prognostic factor for locally advanced nasopharyngeal carcinoma.