This thesis describes the research that investigated molecular biomarkers in defined groups of primary colorectal tumours to determine markers for site specific metastases.
The purpose of the present study was to evaluate the value of discussing rectal cancer patients in a multidisciplinary team (MDT). All treated rectal cancer patients (> T1M0) diagnosed in 2006... Show moreThe purpose of the present study was to evaluate the value of discussing rectal cancer patients in a multidisciplinary team (MDT). All treated rectal cancer patients (> T1M0) diagnosed in 2006-2008 were included. According to the national guidelines, neoadjuvant (chemo)radiotherapy should be given to all rectal cancer patients. Patients were scored as "discussed" (MDT+) only if documented proof was available. The primary endpoint was the number of positive circumferential resection margins (CRM a parts per thousand currency sign1 mm). Of the 275 patients included, 210 were analyzed (exclusions: (recto)sigmoid tumor, acute laparotomy, and inoperability). Neoadjuvant treatment was applied in 174 (83%) patients and followed by total mesorectal excision in 171 (81%) patients. Patients considered not to require downstaging, received short-course radiotherapy (SCRT) (n = 116) or no radiotherapy (no RT) (n = 36), whereas 58 more advanced patients received chemoradiotherapy (CRT). The MDT discussion took place in 116 cases (55%). In the MDT+ group an MRI was used more often (p = 0.001) and TNM staging was more complete (p < 0.001). The proportion of patients with advanced disease was higher in the MDT+ group (88% a parts per thousand yenT3/N+ versus 68%; p = 0.001). The overall CRM+ rate was 13% and did not differ between the MDT+ and the MDT- group (p = 0.392). In patients receiving SCRT or no RT, the CRM+ rate was 10%, whereas the rate was 20% for patients receiving CRT. Although no difference in CRM+ rate was found for those patients who were discussed and those who were not, our results demonstrate room for improvement, especially in the selection of patients for SCRT or no RT. We advocate standardized documentation of treatment decisions and pathology reports. Show less
Background: Accurate staging of colorectal cancer (CRC) with clinicopathological parameters is important for predicting prognosis and guiding treatment but provides no information about organ site... Show moreBackground: Accurate staging of colorectal cancer (CRC) with clinicopathological parameters is important for predicting prognosis and guiding treatment but provides no information about organ site of metastases. Patterns of genomic aberrations in primary colorectal tumors may reveal a chromosomal signature for organ specific metastases. Methods: Array Comparative Genomic Hybridization (aCGH) was employed to asses DNA copy number changes in primary colorectal tumors of three distinctive patient groups. This included formalin-fixed, paraffin-embedded tissue of patients who developed liver metastases (LM; n = 36), metastases (PM; n = 37) and a group that remained metastases-free (M0; n = 25). A novel statistical method for identifying recurrent copy number changes, KC-SMART, was used to find specific locations of genomic aberrations specific for various groups. We created a classifier for organ specific metastases based on the aCGH data using Prediction Analysis for Microarrays (PAM). Results: Specifically in the tumors of primary CRC patients who subsequently developed liver metastasis, KC-SMART analysis identified genomic aberrations on chromosome 20q. LM-PAM, a shrunken centroids classifier for liver metastases occurrence, was able to distinguish the LM group from the other groups (M0&PM) with 80% accuracy (78% sensitivity and 86% specificity). The classification is predominantly based on chromosome 20q aberrations. Conclusion: Liver specific CRC metastases may be predicted with a high accuracy based on specific genomic aberrations in the primary CRC tumor. The ability to predict the site of metastases is important for improvement of personalized patient management. Show less
