RESUMEN
BACKGROUND: It remains unknown whether the tumor stage at initial diagnosis and adjuvant treatments had any impacts on the long-term survival outcomes of patients with triple-negative breast cancer (TNBC) achieving pathologic complete response (pCR) following neoadjuvant chemotherapy (NACT). METHODS: Clinical stage II-III patients with TNBC who achieved pCR after NACT were identified from the Surveillance, Epidemiology, and End Results (SEER) program (SEER cohort) and the National Clinical Research Center for Cancer (Tianjin) in China (TMUCIH cohort). Survival analyses were conducted based on tumor stages and the types of adjuvant treatment received by the patients. The outcomes of interest were overall survival (OS) and breast cancer-specific survival (BCSS). RESULTS: The TMUCIH cohort comprised 178 patients with a median follow-up of 55.5 months. Two and 3 patients experienced BCSS and OS events, respectively. The SEER cohort included 1218 patients with a median follow-up of 65.5 months, where 53 and 78 patients experienced BCSS and OS events, respectively. Patients diagnosed with stage III disease had significantly higher hazards of death compared to stage II disease (OS: hazard ratio [HR], 3.34; 95% confidence interval [CI], 1.84-6.07; P < .001; BCSS: HR, 2.86; 95% CI, 1.38-5.92; P < .001). Adjuvant systemic and radiation therapy did not confer additional benefits to OS and BCSS. CONCLUSION: Tumor stage at initial diagnosis remains an independent predictor of long-term survival outcomes in patients with TNBC achieving pCR after NACT. Postoperative adjuvant chemotherapy and radiation therapy do not appear to provide additional benefit to their long-term prognosis.
RESUMEN
BACKGROUND: The oncologic safety of preserving the pectoralis major fascia (PMF) in patients with breast cancer remains controversial. In this study, we aimed to determine the impact of preserving the PMF on long-term oncologic outcomes in patients with breast cancer treated with immediate implant-based breast reconstruction (IBBR) following conservative mastectomy. METHODS: We selected women with early-stage breast cancer who underwent conservative mastectomy and submuscular IBBR in our center during 2014-2019. The propensity score matching method was used to create well-balanced fascia-preserved and fascia-removed groups. Locoregional recurrence-free survival (LRFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival (OS) rates were calculated using the Kaplan-Meier method and compared using log-rank tests between the fascia-preserved and fascia-removed groups. RESULTS: After matching, there were 219 patients in each group. The mean follow-up time was 64.8 ± 18.1 months for the fascia-preserved group and 64.9 ± 18.4 months for the fascia-removed group. There were no significant differences between the groups in terms of LRFS (91.3% vs. 93.8%; p = 0.818), DMFS (94.0% vs. 92.3%; p = 0.056), DFS (89.9% vs. 88.4%; p = 0.261), and OS (95.8% vs. 95.4%; p = 0.783) rates. In the fascia-preserved group, 61.5% of the locoregional recurrence events occurred within 2 years after surgery. CONCLUSION: Preservation of the PMF did not significantly impact the long-term oncologic outcomes in patients with breast cancer who underwent conservative mastectomy and IBBR. The PMF might be safely preserved in patients without suspicious tumor invasion into this fascia.