Factors Associated with Local Recurrence in Breast Cancer

Abstract

INTRODUCTION: Local recurrence occurs in up to 40% of breast cancer patients. Local recurrence rate is usually around 8% in breast-conserving treatment and 4% after mastectomy. The main factors associated with local recurrence are age, type and grade of histologic differentiation, tumor size, metastasis in axillary lymph nodes, surgical margins of resection, lymphatic vascular invasion, expression of hormone receptors and systemic adjuvant treatment. The aim of the study was evaluate factors associated with locorregional recurrence in breast cancer patients. MATERIAL AND METHODS: One hundred and seventy-three (173) female breast cancer patients undergoing surgery from January 2001 to December 2011 were retrospectively evaluated. The following variables were obtained: age, body mass index (BMI), tumor size, stage, grade of differentiation, lymphatic vascular invasion and axillary lymph node involvement. A descriptive analysis and multiple regression analysis of the factors associated with local recurrence was performed using the WinSTAT program. The significance level adopted was 5%. The study was approved by the Research Ethics Committee of the Sao Marcos Hospital. RESULTS: The mean age of the patients was 57.2 years (31-89 years); mean BMI was 26.51; mean tumor size was 24.7mm (2-115mm). of the total number of patients, 67.23% underwent breast-conserving treatment and 34.73% were treated with mastectomy. Concerning tumor staging, 30.82% of the patients had stage I tumors, 42.14% had stage IIA, 15.09% had stage IIB, 1.89% had stage IIIA and 10.06% had stage IV tumors. None of the patients had IIIB and IIIC tumors. Thirty-five (35%) of the patients had well-differentiated tumors, 61% had moderately differentiated tumors and 58% had poorly differentiated tumors. Regarding axillary status, 78.44% had no axillary involvement and 21.08% had axillary involvement. Furthermore, lymphatic vascular invasion did not occur in 70.7% of the patients and occurred in 29.30% of the patients. In a median follow-up period of 41 months (2- 132 months), the percentage of local recurrence was 2.75% in breast-conserving treatment and 3.45% in mastectomy. On multiple regression analysis, variables such as age, BMI, tumor size, grade of differentiation, lymphatic vascular invasion and axillary lymph node involvement were not associated with local recurrence in breast cancer. Only tumor stage was associated with local recurrence (p=0.01). DISCUSSION: The various factors analyzed are mentioned in the literature in varying degrees of influence regarding the occurrence of local relapse in breast cancer. It is well-known that surgical margin involvement is the main predictive factor for local recurrence. According to the analysis conducted, tumor stage is a factor of major importance, which is in agreement with data from the literature. CONCLUSION: In the present study, tumor staging was associated with local recurrence in surgically treated breast cancer patients.