Relationship between Phosphatase and Tensin Gene Expression and Clinicopathologic Features of Breast Cancer in Patients who Underwent Biopsy or Breast Surgery

Abstract

Background: Phosphatase and tensin (PTEN) gene is a tumor suppressor gene on chromosome 10q23 that is composed of 11 exons. Several studies have shown that loss of PTEN function is a common occurrence in breast cancer in particular in triple negative type, and it is significantly associated with age and higher stage of cancer. In this study, the expression of this gene in malignant breast cancer tissue samples and their correlation with clinicopathologic parameters was studied.
Methods: In this retrospective study, 65 malignant tissue samples were chosen for immunohistochemistry (IHC) test. Other information about clinicopathologic features were collected from pathology reports and patients’ medical records. IHC on the selected paraffin blocks was performed, and the collected data were analyzed using SPSS software and chi-square test. P < 0.0500 was considered statistically significant.
Results: PTEN expression rate in malignant breast tissue was 50.8% of the cases (33 out of 65 samples). Lack of PTEN expression had significant correlation with involvement of the lymph node sent by the sample, vascular or perineural invasion, metastasis and chemotherapy background, spontaneous malignancy presence, familial history, negative progesterone receptor, negative estrogen receptor, and positive her2/neu. No relationship was observed between the expression of PTEN with patients’ age, tumor size, age group of the patients after categorization into two groups of under 50 years and over 50 years, lesion location (left or right breast), and tumor grade.
Conclusions: The results showed PTEN loss as a frequent event in breast cancer that is closely associated with progression and poor prognosis. PTEN loss might predict more aggressive behavior and worse outcomes in patients with breast cancer.