Original Article

Diagnostic Performance of Diffusion-Weighted MRI and FDG PET/CT for Detecting the Local Recurrence of Head and Neck Squamous Cell Carcinoma

10.5152/imj.2016.15010

  • İbrahim İlker Öz
  • İsmail Şerifoğlu
  • Yavuz Sami Salihoğlu
  • Murat Damar
  • Aykut Erdem Dinç
  • Rabiye Uslu
  • Mustafa Çağatay Büyükuysal
  • Oktay Erdem

Received Date: 11.02.2016 Accepted Date: 31.03.2016 IMJ 2016;17(2):48-53

Objective:

To compare the efficacy between diffusion-weighted magnetic resonance imaging (DW-MRI) and positron emission tomography/computed tomography (PET/CT) in detecting the local recurrence of head and neck squamous cell carcinoma (HNSCC) following treatment in the same patient group.

Methods:

Twenty-three patients who had biopsy-proven HNSCC were enrolled. All patients were treated with radiotherapy and followed up with MRI and PET/CT. The median delay times between radiotherapy and MRI and between MRI and FDG PET/CT were 71 days (range: 43–98 days) and 75 days (range: 44–103 days), respectively. Diffusion-weighted single-shot echo planar imaging was performed before contrast injection at b values of 0 and 1000 s/ mm2. PET/CT images were acquired after the administration of 3.7 MBq/kg of fluorine-18-fluorodeoxyglucose, and the images were acquired 1 h later.

Results:

The apparent diffusion coefficient (ADC)mean values of the recurrence group were significantly lower than those of the post-treatment changes group (0.773 vs. 1.588×10−3 mm2/s, respectively; p<0.001). The standardized uptake value (SUV)max values of the recurrence group were significantly higher than those of the post-treatment changes group (15.642 vs. 4.508, respectively; p<0.001). There was no significant correlation between ADCmean and SUVmax values of recurrence (r=0.341; p=0.278), whereas there was a negative correlation between ADCmean and SUVmax values of the post-treatment changes (r=−0.691; p=0.019).

Conclusion:

PET/CT and DW-MRI are effective methods for distinguishing recurrence from post-treatment changes. Follow-up should begin with DW-MRI, and in patients with a suspicion of recurrence, PET-CT should be added to the follow-up protocol.

Keywords: Head and neck cancer, diffusion weighted imaging, apparent diffusion coefficient, positron emission tomography/computed tomography, standardized uptake value