Intratumoral Budding (ITB) in Pre-Operative Biopsies: A Strong Indicator of Lymph Node Positivity in Colon and Rectal Cancer Patients
Heather Dawson, Marion Haedrich, Viktor Koelzer, Daniel Inderbitzin, Markus Borner, Inti Zlobec, Alessandro Lugli. Institute of Pathology, University of Bern, Bern, Switzerland; Inselspital, Bern University Hospital, Bern, Switzerland; Centre Hospital Biel, Biel, Switzerland
Background: Conventional tumor budding in colorectal cancer occurs at the invasion front and despite its well-established value as an indicator of tumor progression cannot be assessed in preoperative biopsies. Nonetheless, tumor budding can be observed within the main tumor body and therefore the term “intratumoral budding, ITB” was introduced in 2011 to describe this occurrence. The aim of this study was to investigate the possible clinical role of ITB in pre-operative biopsies.
Design: Pan-cytokeratin (AE1/AE3) staining was performed on 139 pre-operative biopsies from patients with colorectal cancer treated at the Bern University Hospital, Switzerland between 2002-2011. Based on receiver operating characteristic (ROC) curve analysis, high-grade ITB was defined as >10 buds/hotspot (40x).
Results: On average, 8.2 biopsies were taken per case of which 81% contained cancer. High-grade ITB was detected in 26.6% of all patients and linked to more advanced pT (p=0.02) and pN (p<0.001) stage, higher tumor grade (p=0.004) and lymphatic invasion (p=0.045). The specificity and positive predictive value for lymph node metastasis was 86.7% and 75.6%, respectively. This result was confirmed for patients with either rectal (p=0.033) or colon (p=0.007) cancer and independent of the number of biopsies taken (p=0.008).
Conclusions: ITB predicts lymph node positivity in both colon and rectal cancer and therefore should be considered in the pre-operative management of these patients.
Monday, March 4, 2013 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 93, Monday Morning