P-0285 - Magnetic resonance diffusion as predictive value of response to treatment with chemo-radiotherapy in patients with locally advanced rectal cancer

Date 28 June 2014
Event World GI 2014
Session Poster Session
Topics Anti-Cancer Agents & Biologic Therapy
Rectal Cancer
Imaging, Diagnosis and Staging
Surgery and/or Radiotherapy of Cancer
Presenter Inmaculada Gallego Jimenez
Citation Annals of Oncology (2014) 25 (suppl_2): ii14-ii104. 10.1093/annonc/mdu165
Authors I. Gallego Jimenez1, M. Fernández-Parra Eva1, D. Morales Pancorbo1, J. Salvador Bofill Francisco1, S. Rico Gala1, A. López-Ladrón2
  • 1Hospital Nuestra Señora de Valme, Sevilla/ES
  • 2H Nuestra Señora de Valme, Sevilla/ES



Treatment with chemotherapy and preoperative radiotherapy in locally advanced rectal cancer, has allowed to obtain complete pathological responses or decreased tumor stage, reducing the number of local relapse of the disease. It has been reported that the diffusion MRI (DMRI) allows to monitor tumor response to treatment and can be used as a predictor of the same depending on the values of apparent diffusion coefficient (ADC) before the start of treatment. Our objective was to evaluate whether ADC values are associated with pathological response to treatment in our patients.


Prospective pilot cohort in which patients were included according to the following study inclusion criteria: 1) age> 18 years, 2) diagnosis of locally advanced rectal cancer metastatic, 3) treatment with chemoradiotherapy with capecitabine (825 mg/m2 every 12 hours) concomitant with radiotherapy (50.4 Gray). The primary endpoint was the pathological response. This patient was classified according to two parameters: 1) anatomical-pathological (AP) response treatment (full versus no complete response), 2) Grade tumor regression (GRT) of Mandard (GRT 1 versus GRT 2 -4). All patients have DMRI protocol to the diagnosis and 5 weeks after of stopping treatment. The association ADC values before and after treatment, and the primary endpoint was analyzed.


13 patients were included in the study. The median (Q1-Q3) age of the patients was 64 (61-66) years. ADC values decreased significantly at the end of treatment. The median pretreatment CDA is 919 mm2/s, while the end is 665 mm2 /s at p = 0.003. ADC values pre-treatment tend to associate with the AP response to treatment. Specifically median CDA in patients showing complete response was 759 (728-971) mm2/s, while the median of CDA in the remaining patients is 668 (509-813) mm2/s with p = 0.1. Moreover, the pretreatment values CDA, predicting the degree of tumor response. So, there were statistically significant differences between patients who had presented GR1 versus those GR2-GR4 (782 [731-940]) versus (665 [466-716]) with p = 0.03. By contrast, there was no association between ADC values after treatment and pathological response. So ADC median post-treatment is 913 (725-1139) mm2 /s in patients with complete response and 919 (819-961) mm2 /s in the remaining patients with p = 0.6. With respect to the degree of tumor regression, median CDA in patients with GR1 was 975 (750-1101) mm2/s, whereas in patients with GR2-4 was 896 (800-955) p = 0.3.


Our results support the use of RMD as predictive value of response to neoadjuvant combination therapy in patients with locally advanced rectal cancer metastatic.