Retrospective Analysis of Parameters Affecting Metastatic Breast Cancer

While metastatic breast cancer (MBC), which is the most common cause of death in women, has been seen as an incurable surgical problem in the past decade, as the heterogeneous nature of breast cancer becomes clear with increasing molecular studies and advances in oncological protocols, life expectancy is increasing. In this study, we aimed to examine the clinicopathological features of the patients we followed up with MBC.

Patients who were operated on with the diagnosis of breast cancer in our hospital between 2018 and 2023 and who were later found to have metastases were retrospectively analyzed from the database. The age of the patients, the histological and molecular type, stage and grade of the tumor, the time from diagnosis to metastasis, the location of metastasis, the duration of treatment and follow-up were investigated. Patients who were operated on in other centers and/or were out of follow-up were excluded from the study. For the statistical analysis of the findings, number cruncher statistical system (NCSS) 2020 statistical software (NCSS LLC, Kaysville, Utah, USA) was used at a significance level of 0.05.

Metastasis was detected in 77.1% (n=37) of a total of 48 female patients, and recurrence was found in 22.9% (n=11). The mean age of the patients was 57 years. There was no statistically significant difference between the patients in terms of demographics. When evaluated according to the TNM stage, 24.3% (n=9) of the patients were in the early stage and 75.7% (n=28) were in the locally advanced stage; the number of locally advanced patients was found to be higher than the early stage. In histology examination, 27.1% (n=13) of the patients were luminal A, 31.3% (n=15) luminal B, 16.7% (n=8) HER2 positive, and 25% (n=12) triple negative. Ki67 was higher than 14% in 64.6% (n=31) patients. Breast conserving surgery was performed in 41.6% (n=20) of the patients, and mastectomy was performed in 58.3% (n=28) patients. Metastasis in 34.2% (n=13) of the cases within 1-2 years, in 42.1% (n=16) within 2-5 years, and in 23.7% (n=9) after 5 years took place. Sites of metastasis were bone (37.7%, n=28), liver (28.9%, n=11), brain (10.5%, n=4), and lung (7.9%, n=3). More than one metastasis site was observed in 21.05% (n=8) of patients with metastases. There was no statistically significant difference between luminal A, luminal B, HER 2 groups and triple-negative breast cancer in terms of metastasis time and location (p>0.05). Adjuvant hormone therapy was more common in the luminal A group, whereas neoadjuvant therapy was more common in the HER2+ group. A total of 20 deaths were observed in 48 patients (41.7%). The median disease-free survival was 64 months.

Despite all the developments in metastatic breast cancer, the 5-year survival rate is 27%. Targeted personalized therapies may be promising when the mechanism of metastasis and specific pathways in breast cancer emerge.