Assessment of HER2 and Ki67 in adenocarcinomas

Biomarkers in tumor tissue can predict cancer behavior or can be targeted with targeted therapy. Two examples of such biomarkers are HER2 and Ki67. These biomarkers are assessed with stains on tissue of patients in clinical pathology. Timco Koopman is a resident in pathology and works at the pathology department of the UMCG. For his thesis he researched the quantitative assessment of HER2 and Ki67 in malignant tumors of glandular tissue (adenocarcinomas). HER2 is a receptor protein that is best known from breast and stomach cancer. Anti-HER2-therapy for HER2-positive tumors of these organs can increase a patient’s chances of curation and survival. Ki67 is a protein that is present in dividing cells. As such, quantification of Ki67 reflects the growth speed and aggressiveness of tumors. The first part of the thesis is about HER2. Koopman explored the prevalence of HER2-positivity in gastric and esophageal cancer and describes how HER2 should be determined in these tumors. Koopman also describes why assessment of HER2 in other tumors than breast, stomach or esophagus can be more problematic. The second part of the thesis is about digital image analysis. Digitizing in modern pathology is on the rise. Digitized images can be analyzed with specific software. Koopman describes why digital image analysis in clinical pathology will benefit the reliability and reproducibility of the assessment of HER2 and Ki67