Apparent diffusion coefficient histogram analysis for predicting neoadjuvant chemoradiotherapy response in patients with rectal cancer

Babatürk A., Erden A., Geçim İ. E.

Diagnostic and Interventional Radiology, cilt.28, sa.5, ss.403-409, 2022 (SCI-Expanded) identifier identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 28 Sayı: 5
  • Basım Tarihi: 2022
  • Doi Numarası: 10.5152/dir.2022.201112
  • Dergi Adı: Diagnostic and Interventional Radiology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, EMBASE, MEDLINE, TR DİZİN (ULAKBİM)
  • Sayfa Sayıları: ss.403-409
  • Ankara Üniversitesi Adresli: Evet

Özet

© Author(s).PURPOSE This study aimed to retrospectively evaluate the apparent diffusion coefficient (ADC) histograms in predicting chemoradiotherapy (CRT) response in patients with locally advanced rectal cancer (LARC). METHODS A total of 51 patients who underwent surgery in our institution for rectal cancer following neo-adjuvant CRT between November 2013 and July 2019 were enrolled. Conventional magnetic resonance (MR) and diffusion-weighted images obtained before and after CRT were evaluated retrospectively. All tumor-containing regions of interests were drawn in 3 selected axial images, and special software for histogram analysis was used to evaluate ADC distribution. ADC cutoff values from post-CRT ADC histogram were calculated from receiver operating characteristic (ROC) analysis for evaluating CRT response. RESULTS In histopathological analysis, 5 patients (9.8%) had minimal response (group 1), 31 patients (60.8%) had partial response (group 2), and 15 patients (29.4%) had complete or almost complete response (group 3). In the ADC histogram, minimum, maximum, 10th, 25th, 50th, 75th, and 90th percentile, mean ADC values, and skewness values of groups 2 and 3 showed significant changes before and after CRT, but no difference was found within group 1 values. The mean, 25th, 50th, 75th percent ADC values after CRT and skewness, and kurtosis values were significantly different between group 1 and group 3. Skewness value from the ADC histogram in post-CRT magnetic resonance imaging had the best diagnostic performance with an area under the ROC curve of 0.851 (P = .003) for detecting group 3. The skewness cutoff calculated from the ROC analysis was 0.210 for evaluating CRT response. The sensitivity and specificity of the cut-off value were 100% and 61.4%, respectively. CONCLUSION The ADC histogram analysis seems to have potential application in predicting response to neo-adjuvant CRT in patients with locally advanced rectal cancer.