A Retrospective Study of Prevalence, Metastatic Patterns and Survival Among Female Breast Cancer Patients of Different Intrinsic Subtypes Stratified According to St. Gallen 2013 International Expert Consensus
Chanyoot Bandidwattanawong MD1, Naruedol Chalermsuksant MD1
Affiliation : 1 Medical Oncology Unit, Department of Internal Medicine, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Bangkok, Thailand
Objective : To determine the prevalence, metastatic pattern, and clinical outcomes of patients with each breast cancer subtype
stratified according to 2013 St Gallen consensus.
Materials and Methods : We conducted a retrospective descriptive study on breast cancer patients treated in Vajira Hospital
from January 1, 2006 to December 31, 2011. Clinico-pathologic data including survival of the patients were collected.
Results : There were 169 breast cancer patients. Seventeen patients were stage I (10.1%), 61 were stage II (36.1%), 65 were
stage III (38.5%) and 26 were stage IV (15.4%) at presentation. There were 66 patients (39.1%) classified into Luminal A,
41 patients (24.2%) in Luminal B, 31 patients (18.3%) in HER-2 enriched, and 31 patients (18.3%) in triple-negative
subtype, respectively. After median follow-up of 60 months (IQR 26 to 88), the patients in luminal subtypes infrequently
recurred and usually had metastatic sites in non-visceral organs, while HER-2 enriched and triple negative usually recurred
within the first few years after diagnosis and had metastatic sites in visceral organs.
Conclusion : Stratification of breast cancer patients into subtypes based on 2013 St Gallen Consensus is robust. It is the
cheaper and more practical tool compared to molecular techniques.
Keywords : breast cancer, intrinsic subtypes, St Gallen 2013
