Predicting Treatment Response of Colorectal Cancer Liver Metastases to Conventional Lipiodol-Based Transarterial Chemoembolization Using Diffusion-Weighted MR Imaging: Value of Pretreatment Apparent Diffusion Coefficients (ADC) and ADC Changes Under Therapy.

Abstract

PURPOSE:

To use absolute pretreatment apparent diffusion coefficients (ADC) derived from diffusion-weighted MR imaging (DWI) to predict response to repetitive cTACE for unresectable liver metastases of colorectal carcinoma (CRLM) at 1 and 3 months after start of treatment.

MATERIALS AND METHODS:

Fifty-five metastases in 34 patients were examined with DWI prior to treatment and 1 month after initial cTACE. Treatment was performed in 4-week intervals. Response was evaluated at 1 and 3 months after start of therapy. Metastases showing a decrease of ≥30% in axial diameter were classified as responding lesions.

RESULTS:

One month after initial cTACE, seven lesions showed early response. There was no significant difference in absolute pretreatment ADC values between responding and non-responding lesions (p = 0.94). Three months after initial cTACE, 17 metastases showed response. There was a significant difference (p = 0.021) between absolute pretreatment ADC values of lesions showing response (median 1.08 × 10-3 mm2/s) and no response (median 1.30 × 10-3 mm2/s). Pretreatment ADC showed fair diagnostic value to predict response (AUC 0.7). Lesions showing response at 3 months also revealed a significant increase in ADC between measurements before treatment and at one month after initial cTACE (p < 0.001). Applying an increase in ADC of 12.17%, response at 3 months after initial cTACE could be predicted with a sensitivity and specificity of 77 and 74%, respectively (AUC 0.817). Furthermore, there was a strong and significant correlation (r = 0.651, p < 0.001) between percentage change in size after third cTACE and percentage change in ADC.

CONCLUSION:

In patients with CRLM, ADC measurements are potential biomarkers for assessing response to cTACE.

• Authors: Maximilian Lahrsow, Moritz H Albrecht, Matthew W Bickford, Thomas J Vogl
• Journal: Cardiovascular and interventional radiology (Cardiovasc Intervent Radiol) Vol. 40 Issue 6 Pg. 852-859 (Jun 2017) ISSN: 1432-086X [Electronic] United States
• PMID: 28357571 (Publication Type: Journal Article)

Chemical References

• Ethiodized Oil

Topics

• Adult
• Aged
• Aged, 80 and over
• Chemoembolization, Therapeutic (methods)
• Colorectal Neoplasms (diagnostic imaging, therapy)
• Diffusion Magnetic Resonance Imaging (methods)
• Embolization, Therapeutic
• Ethiodized Oil
• Female
• Humans
• Liver Neoplasms (diagnostic imaging, secondary, therapy)
• Male
• Middle Aged
• Retrospective Studies
• Sensitivity and Specificity
• Treatment Outcome