Identification of Local Recurrence and Radiofibrosis by Computed Tomography Perfusion on Nasopharyngeal Carcinoma After Radiotherapy

Purpose

The aim of this study was to investigate the role of perfusion computed tomography (CT) for identification of local recurrence (LR) and radiofibrosis (RF) in patients with nasopharyngeal carcinoma after radiotherapy.

Methods

Forty-eight prospective patients were recruited for this study. NPC diagnosis was confirmed by pathologic biopsy examination. Immunohistochemistry staining was used on biopsy specimens, and microvessel density was calculated by microscopy. Perfusion CT was performed on both the LR group (n = 31) and the RF group (n = 17) after intravenous injection of contrast medium. Time-density curve, blood flow, blood volume, and mean transit time, as well as permeability surface area product, were analyzed as perfusion CT parameters. The microvessel density was compared between both the LR and RF groups.

Results

There is a significant difference between the LR and RF groups in microvessel density, the time density curve, blood flow blood volume, mean transit time, and the permeability surface area product (P < .01).

Conclusions

The results demonstrate that perfusion CT is a reliable and accurate method to identify LR and RF after radiotherapy in patients with nasopharyngeal carcinoma.