Impact of de novo metastatic breast cancer on survival of patients: A comparative retrospective observational study

İngilizce (OpenAlex)

Objective: The aim is to compare the characteristics of de novo metastatic BC (dnMBC) and recurrent metastatic BC (rMBC). Materials and Methods: The population of this retrospective observational study consisted of female patients with histologically confirmed de novo and recurrent metastatic BC diagnosed and treated in a tertiary referral center between 2010 and 2019. Patients’ demographic, clinical, and tumor characteristics were obtained from their medical records. Overall survival (OS) was calculated for each patient from the time of metastatic BC diagnosis. Statistical analyses were performed to compare the patients with de novo and recurrent metastatic BC according to their sociodemographic and clinical characteristics. Results: Of the 322 patients included in the study, 109 (33.9%) had de novo metastatic BC (dnMBC), and 213 (66.1%) had recurrent metastatic BC (rMBC). Patients with dnMBC were significantly older (p<0.001) and had higher Eastern Cooperative Oncology Group performance status (p<0.001) than those with rMBC. There were also significantly more postmenopausal patients in the dnMBC group than in the rMBC group (p<0.001). Significant differences were detected between the groups in multicentricity/multifocality (p=0.017), human epidermal growth factor receptor 2 positivity (p=0.010), T-stage tumor (p<0.001), and N-stage tumor rates (p<0.001), and tumor marker levels (p<0.05). On the other hand, there was no significant difference between the dnMBC and rMBC groups in metastatic spread patterns (p>0.05) or median OS (29.0 months and 21.0 months, respectively; p=0.152). Conclusions: In conclusion, no significant difference was found in OS between patients with dnMBC and rMBC. Hence, considering that the variations in clinical subtype distribution, tumor grade, and first-line treatment modalities may confound the survival outcomes in BC