Risk factors of developing contralateral breast cancer after first primary breast cancer treatment.

BACKGROUND: Breast cancer (BC) is the most common cancer among women worldwide. Increased survival of primary BC (PBC) has increased contralateral breast cancer (CBC) and become a health problem. AIMS: This study aimed to determine the effect of disease-free interval (DFI), risk factors and PBC characteristics on the progression of CBC within primary BC survivors. METHODS AND RESULTS: This retrospective study identified 5003 women diagnosed with breast cancer between 2000 and 2020 in the cancer research center. The study included 145 CBC and 4858 PBC survivors, with CBC diagnosed at least 6 months after the detection of primary BC. ER+, PR+, and HER2+ were reported in 72.13%, 66.67%, and 30% of CBC patients. Invasive ductal carcinoma (IDC) BC was reported in 69.57% of patients, and 81.90% and 83.64% of the patients were treated with adjuvant chemotherapy and external radiotherapy. The Kaplan-Meier method indicated that the median time interval between PBC and CBC was 3.92 years, and the 5-year DFI was 97%. The Cox proportional hazard regression model indicated that although more than half of the participants had no family history of BC (69.57%), women 60 years and older were negatively associated with CBC. CONCLUSION: This study provides the first investigation of CBC and DFI risk factors among PBC survivors in Iran. Age was found to be negatively associated with CBC development particularly after the age of 60, indicating the necessity of tracking CBC survivors carefully in this age group.

Intraoperative pathologically-calibrated diagnosis of lymph nodes involved by breast cancer cells based on electrical impedance spectroscopy; a prospective diagnostic human model study.

BACKGROUND: Nodal status evaluation is a crucial step in determining prognostic factors and managing treatment strategies for breast cancer patients. Preoperative (CNB), intraoperative (SLNB), and even postoperative techniques (Formalin-Fixed Paraffin-Embedded sectioning, FFPE) have definite limitations of precision or sometimes are time-consuming for the result declaration. The primary purpose of this prospective study is to provide a precise complementary system for distinguishing lymph nodes (LNs) involved by cancerous cells in breast cancer patients intraoperatively. METHODS: The proposed system, Electrical Lymph Scoring(ELS), is designed based on the dielectric properties of the under-test LNs. The system has a needle-shaped 2-electrode probe entered into SLNs or ALNs dissected from patients through standard surgical guidelines. Impedance magnitude in f = 1 kH (Z1kHz) and Impedance Phase Slope in frequency ranges of 100 kHz-500 kHz (IPS) were then extracted from the impedance spectroscopy data in a cohort study of 77 breast cancer patients(totally 282 dissected LNs) who had been undergone surgery before (n = 55) or after (n = 22) chemical therapies (non-neoadjuvant or neoadjuvant chemotherapy). A new admittance parameter(Yn') also proposed for LN detection in neoadjuvant chemotherapy patients. RESULTS: Considering the permanent pathology result as the gold standard checked by two independent expert pathologists, a significant correlation was observed between the presence of cancerous cells in LNs and individual ranges of the ELS electrical responses. Compared with normal LNs containing fatty ambient and immune cells, LNs involved by cancerous clusters would reduce the Z1kHz and increase the IPS. These changes correlate with fat metabolism by cancer cells due to their Fatty Acid Oxidation (FAO) in LN, which results in different dielectric properties between high and low-fat content of normal and cancerous LNs, respectively. CONCLUSIONS: By finding the best correlation between our defined impedimetric parameters and pathological states of tested LNs, a real-time intraoperative detection approach was developed for highly-sensitive (92%, P<0.001) diagnosis of involved sentinel or axillary LNs. The impact of real-time intraoperative scoring of SLNs would make a pre-estimation about the necessity of excising further LNs to help the surgeon for less invasive surgery, especially in the absence of frozen-section equipment.