Texture analysis of tumors may be biomarker in localized esophageal cancer
Computed tomography (CT) texture analysis of primary tumors may be a potential imaging biomarker in localized esophageal cancer following neoadjuvant chemotherapy.
This study evaluated the tumoral texture analysis on baseline and posttreatment CT scans of 31 patients with localized resectable esophageal cancer patients. The patients had a median age of 63 years and had received neoadjuvant chemotherapy between 2007 and 2010. CT scans were performed before and after the use of chemotherapy, as well as prior to surgery. All the patients received platinum and fluorouracil-based chemotherapy followed by surgery.
Texture parameters of mean-grey level intensity (MGI), entropy, uniformity, kurtosis, skewness, and standard deviation of histogram (SDH) were derived for four filter values. These texture parameters highlighted structures with different spatial widths. A width of 1.0 was defined as fine texture, 1.5 to 2.0 as medium, and 2.5 as coarse. Median follow-up was 21.9 months.
Primary tumors became more homogenous following chemotherapy, as entropy decreased and uniformity increased. A smaller change in skewness following chemotherapy was a significant prognostic factor—median overall survival was 36.1 months versus 11.1 months. Lower baseline entropy and lower posttreatment MGI were also associated with improved survival, although they demonstrated only a trend toward significance.
Texture analysis of the CT scans is a postprocessing step, which was done utilizing proprietary software (TexRAD) that enhances the images in ultrafine detail not visible to the human eye. Certain tumoral features changed consistently following chemotherapy, and some features were associated with overall survival.
“Though these results are for a very small number of patients, they suggest that the tumoral texture features may provide valuable information that could help us to distinguish which patients will do well following chemotherapy and which ones will do poorly,” said lead study author Connie Yip, MD, of King's College London, United Kingdom, and of the National Cancer Centre, Singapore. “As a biomarker for treatment efficacy, this technique could save patients from unnecessary surgery and provide more definitive guidance in developing patient treatment plans with improved outcomes.”
This research was presented at the 2013 Cancer Imaging and Radiation Therapy Symposium in Orlando, Florida, which is sponsored by the American Society for Radiation Oncology and the Radiological Society of North America.