Advanced pancreatic cancer: the use of the apparent diffusion coefficient to predict response to chemotherapy

Abstract

The purpose of this study was to determine if the apparent diffusion coefficient (ADC) on diffusion-weighted MRI could predict the response of patients with advanced pancreatic cancer to chemotherapy. Diffusion-weighted MRI was performed in 63 consecutive patients with advanced pancreatic cancer who were subsequently treated with chemotherapy. The ADC values of the primary tumour with a middle b-value (400 s mm(-2)) and a high b-value (1000 s mm(-2)) were determined; cystic or necrotic components were avoided. The patients were classified into two groups: (i) those with progressive disease and (ii) those who were stable 3 months and 6 months after initial treatment. The groups were compared with respect to the ADC and clinical factors, including gender, age, Union International Contre le Cancer (UICC ) stage, initial tumour size and chemotherapy agents used. Local tumour progression rates were evaluated using the Kaplan-Meier method. The middle b-value ADC of the pancreatic cancers ranged from 0.93-2.42 x10(-3) mm(2) s(-1) (mean, 1.50 x10(-3) mm(2) s(-1)), and the high b-value ADC ranged from 0.72-1.88 x10(-3) mm(2) s(-1) (mean, 1.20 x10(-3) mm(2) s(-1)). The high b-value ADC was significantly different between the progressive and stable groups at 3 months' and 6 months' follow-up (p = 0.03 and p = 0.04, respectively). The rate of tumour progression was significantly higher in those with a lower high b-value ADC than in those with a higher b-value ADC (median progression time, 140 days vs 182 days; p = 0.01). In conclusion, a lower high b-value ADC in patients with advanced pancreatic cancer may be predictive of early progression in chemotherapy-treated patients.

Value of diffusion-weighted MRI and apparent diffusion coefficient measurements for predicting the response of locally advanced rectal cancer to neoadjuvant chemoradiotherapy

“…Previous studies have suggested that quantitative interpretation of the ADC can be used as a biomarker for treatment response in several tumors [31][32][33]. However, this matter is still controversial in rectal cancer [17,30,34].…”

Whole-Body Diffusion-weighted MR Imaging in Cancer: Current Status and Research Directions

“…Tumor hypoxia is known to mediate resistance to chemotherapy, radiation therapy, and photodynamic therapy, leading to the selection of aggressive tumor cell clones capable of evading the hostile tumor microenvironment ( 70 , 71 ). However, the association between high ADC and less favorable response to treatments does not apply to all therapy types ( 72 ). Indeed, the opposite has been found for vascular disruptive agents, which are known to induce massive central necrosis in tumors.…”

Usefulness of diffusion-weighted MR imaging in the evaluation of pulmonary lesions

“…Investigators have reported the usefulness of ADC measurement for characterising tumours [4][5][6]. The ability to measure the rate of water diffusion within tissue is important, as water diffusion is frequently altered in various disease processes and may reflect physiological and morphological characteristics, such as cell density and tissue viability [7].…”