Sung Jun Moon1, Seung Hyun Cho2, Gab Chul Kim1, Won Hwa Kim1, Hye Jung Kim1, Kyung-Min Shin1, So Mi Lee1, Jun Seok Park3, Gyu-Seog Choi3, See Hyung Kim4. 1. Department of Radiology, Kyungpook National University Medical Center, School of Medicine, Kyungpook National University, 807 Hoguk-ro, Buk-gu, Daegu, 702-210, Republic of Korea. 2. Department of Radiology, Kyungpook National University Medical Center, School of Medicine, Kyungpook National University, 807 Hoguk-ro, Buk-gu, Daegu, 702-210, Republic of Korea. shcho2405@gmail.com. 3. Colorectal Cancer Center, Kyungpook National University Medical Center, School of Medicine, Kyungpook National University, 807 Hoguk-ro, Buk-gu, Daegu, 702-210, Republic of Korea. 4. Department of Radiology, Dongsan Hospital, College of Medicine, Keimyung University, 56 Dalseong-ro, Jung-gu, Daegu, 700-712, Republic of Korea.
Abstract
PURPOSE: To assess the complementary prognostic value of pre-treatment tumor apparent diffusion coefficient (ADC) for the prediction of tumor recurrence in patients with rectal cancer. METHODS: From March 2012 to March 2013, a total of 128 patients with mid/lower rectal cancer who underwent pre-treatment rectal MRI were enrolled in this retrospective study. Two radiologists in consensus evaluated conventional imaging features (Cimg) in pre-treatment rectal MRI: tumor height from anal verge (≤5 cm vs. >5 cm), T stage (high vs. low), the presence or absence of lymph node metastasis, mesorectal fascia invasion, and extramural venous invasion. The mean tumor ADC values (TumorADC) based on high b-value (0, 1000 × 10(-3) mm(2)/s) diffusion weight images were extracted. A multivariate Cox proportional hazard (CPH) regression was performed to evaluate the association of Cimg and TumorADC with the 3-year local recurrence (LR) rate. Predictive performance of two multivariate CPH models (Cimg only vs. Cimg + TumorADC) was compared using Harrell's c index (HCI). RESULTS: TumorADC (Adjusted HR, 7.830; 95% CI 3.937-15.571) and high T stage (Adjusted HR, 8.039; 95% CI 2.405-26.874) were independently associated with the 3-year LR rate. The CPH model generated with T stage + TumorADC (HCI, 0.820; 95% CI 0.708-0.932) showed significantly higher HCI than that with T stage only (HCI, 0.742; 95% CI 0.594-0.889) (P = 0.009). CONCLUSIONS: In patients with mid/lower rectal cancer, integrating TumorADC to Cimg increases predictive performance of the CPH model than that with Cimg alone for the prediction of LR within 3 years after surgery.
PURPOSE: To assess the complementary prognostic value of pre-treatment tumor apparent diffusion coefficient (ADC) for the prediction of tumor recurrence in patients with rectal cancer. METHODS: From March 2012 to March 2013, a total of 128 patients with mid/lower rectal cancer who underwent pre-treatment rectal MRI were enrolled in this retrospective study. Two radiologists in consensus evaluated conventional imaging features (Cimg) in pre-treatment rectal MRI: tumor height from anal verge (≤5 cm vs. >5 cm), T stage (high vs. low), the presence or absence of lymph node metastasis, mesorectal fascia invasion, and extramural venous invasion. The mean tumor ADC values (TumorADC) based on high b-value (0, 1000 × 10(-3) mm(2)/s) diffusion weight images were extracted. A multivariate Cox proportional hazard (CPH) regression was performed to evaluate the association of Cimg and TumorADC with the 3-year local recurrence (LR) rate. Predictive performance of two multivariate CPH models (Cimg only vs. Cimg + TumorADC) was compared using Harrell's c index (HCI). RESULTS: TumorADC (Adjusted HR, 7.830; 95% CI 3.937-15.571) and high T stage (Adjusted HR, 8.039; 95% CI 2.405-26.874) were independently associated with the 3-year LR rate. The CPH model generated with T stage + TumorADC (HCI, 0.820; 95% CI 0.708-0.932) showed significantly higher HCI than that with T stage only (HCI, 0.742; 95% CI 0.594-0.889) (P = 0.009). CONCLUSIONS: In patients with mid/lower rectal cancer, integrating TumorADC to Cimg increases predictive performance of the CPH model than that with Cimg alone for the prediction of LR within 3 years after surgery.
Entities:
Keywords:
Apparent diffusion coefficient (ADC); Diffusion-weighted image (DWI); Magnetic resonance imaging (MRI); Prognosis; Rectal cancer