Validity of St Gallen risk categories in prognostication of breast cancer patients in Southern Sri Lanka

Breast Cancer Survival in Sri Lanka

PURPOSE

In this study, we report survival data of the largest cohort of patients with breast cancer in Sri Lanka.

PATIENTS AND METHODS

All female patients with histologically confirmed breast cancer treated at a single unit at the National Cancer Institute of Sri Lanka between 1994 and 2006 were included in the study. Clinical records were reviewed and data obtained on the following clinical and pathologic factors: age, histology, stage at presentation, grade, and immunohistochemistry profile. Treatment details such as type of surgery and use of systemic chemotherapy, hormonal therapy, trastuzumab, and radiation therapy were also collected. In localized cancer, disease-free survival (DFS) was the primary end point, while in patients who presented with de novo metastases, progression-free survival (PFS) was the primary end point.

RESULTS

A significant proportion of patients presented with de novo metastases (14%) and locally advanced disease (18%). While 57% of patients had hormone-sensitive tumors, human epidermal growth factor receptor 2 overexpression was seen in 14%, and 29% had triple-negative tumors. Only 3% of patients with localized disease were treated with breast-conserving surgery, with the rest undergoing modified radical mastectomy. The 5- year DFS rate was 71.6% (95% CI, 69.2 to 74.0) in patients with localized disease. The median PFS in patients with metastatic disease was 20 months (95% CI, 18 to 22 months), while the median overall survival was 30 months (95% CI, 32 to 35 months). On multivariable analysis, immunohistochemical group and stage were prognostic factors in localized disease, while in patients with metastases, immunohistochemical group and tumor grade were associated with PFS.

CONCLUSION

More effective screening and early detection programs along with increasing breast-conserving surgery will improve breast cancer outcomes in Sri Lanka.

Application of St Gallen Categories in Predicting Survival for Patients With Breast Cancer in Vietnam

Breast cancer is a heterogeneous disease with different tumor subtypes. Identifying risk categories will help make better treatment decisions. Hence, this study aimed to predict the survival outcomes of invasive breast cancer in Vietnam, using St Gallen 2007 classification. This study was conducted on 501 patients with breast cancer who had surgical operations, but had not received neoadjuvant chemotherapy, from 2011 to 2013. The clinicopathological characteristics were recorded. Immunohistochemistry staining was performed on ER, PR, HER2/neu, and Ki67 markers. For HER2/neu(2+), fluorescence in situ hybridization was used as the test. All patients with breast cancer were stratified according to 2007 St Gallen categories. Kaplan-Meier and log-rank models were used to analyze survival rates. There were 3.8% cases classified as low risk (LR), 72.1% as intermediate risk (IR1: 60.1% and IR2: 12.0%), and 24.1% as high risk (HR1: 11.8% and HR2: 12.3%). Patients who were LR had the best prognosis, with a 5-year overall survival (OS) rate of 100%. Intermediate-risk patients were at 92.3%. High-risk patients had the worst prognosis, with a 5-year OS proportion of 69.3% (P < .05). For disease-free survival (DFS), risk categories were categorized as LR: 100%, IR: 90.3%, and HR: 69.3% (P < .05). Three main risk categories of breast cancer had a distinct OS and DFS. These findings suggest that the 2007 St Gallen risk category could be used to stratify patients with breast cancer into different risk groups in Vietnam.