Different prognosis of young breast cancer patients in their 20s and 30s depending on subtype: a nationwide study from the Korean Breast Cancer Society.

PURPOSE: Numerous studies have demonstrated that breast cancer in young women (BCY) has unfavorable prognostic features and more unfavorable subtypes. However, few studies have evaluated the effect of subtype disparities on breast cancer prognosis by age, especially for BCY. We analyzed breast cancer mortality stratified by tumor subtype according to age among patients younger than 50 years. METHODS: Data from the Korean Breast Cancer Society Registry for patients diagnosed with invasive breast cancer when aged less than 50 years between 2003 and 2010 were reviewed retrospectively. RESULTS: We identified 30,793 patients with breast cancer who were eligible for analysis. Of these, 793 (2.6%) were aged 20-29 and 8926 (28.8%) were aged 30-39. Median follow-up duration was 84 months. Mean age was 42.4 years. Patients in their 20s were more likely to have cancer of advanced stage and higher nuclear grade, present with lymphovascular invasion, and have unfavorable subtypes. Patients in the 20s group showed worse prognosis. In multivariate analysis for overall survival (OS), the hazard ratio (HR) for patients in the 20s group was higher than that for the 30s and 40s groups, and patients with triple-negative breast cancer (TNBC) showed higher HR than patients with HER-2 or luminal subtype (all p < 0.0001). When stratified by subtype, luminal subtype showed significantly worse prognosis in the 20s group than the 30s and 40s groups, whereas HER-2 and TNBC subtypes showed no significant difference. CONCLUSION: Patients in their 20s with breast cancer had unfavorable characteristics and worse prognosis than patients in their 30s and 40s. When stratified by tumor subtype, patients in their 20s with luminal subtype of breast cancer showed worse prognosis than older patients, whereas HER-2 and TNBC subtypes showed no significant differences.

Survival Outcomes of Patients With Breast Cancer Diagnosed Using Vacuum-Assisted Biopsy: A Nationwide Study From the Korean Breast Cancer Society.

PURPOSE: Breast cancer is mainly diagnosed using core needle biopsy (CNB), although other biopsy methods, including vacuum-assisted biopsy (VAB), may also be used. We compared differences in clinical characteristics and prognoses of patients with breast cancer according to biopsy methods used for diagnosis. METHODS: A total of 98,457 patients who underwent various biopsy methods (CNB, fine-needle aspiration [FNA], VAB, and excisional biopsy) for diagnosing breast cancer were recruited. Using CNB as a reference, related clinicopathological factors and prognostic differences between biopsy methods were analyzed retrospectively using large-scale data from the Korean Breast Cancer Society Registration System. The associations between biopsy methods and clinicopathological factors were compared using multinomial logistic regression analysis, and the prognoses of patients undergoing the different biopsy methods, as breast cancer-specific survival (BCSS) and overall survival (OS), were compared using the Kaplan-Meier method and Cox proportional hazard model. RESULTS: Univariate and multivariate analyses showed that unlike FNA, both VAB and excisional biopsy were significantly associated with tumor size, palpability, tumor stage, and histologic grade as relatively good prognostic factors compared to CNB. In particular, VAB showed lower odds ratios for these factors than excisional biopsy. In the univariate analysis, the prognosis of patients undergoing VAB was better than that of those undergoing CNB with respect to BCSS (hazard ratio [HR], 0.188, p < 0.001) and OS (HR, 0.359; p < 0.001). However, in the multivariate analysis, there were no significant prognostic differences from CNB in both BCSS and OS; differences were only evident for FNA. CONCLUSION: In this study, we showed that the characteristics of breast cancer differed according to various biopsy methods. Although VAB is not a standard method for breast cancer diagnosis, it showed no prognostic differences to CNB.

Is mastectomy with immediate reconstruction safe for patients undergoing neoadjuvant chemotherapy? A nationwide study from Korean Breast Cancer Society.

PURPOSE: In this study, we compared the prognoses of patients who underwent mastectomy with immediate breast reconstruction (IBR) after neoadjuvant chemotherapy with those who underwent mastectomy. METHODS: This retrospective study included 87,995 patients who were surgically treated for primary breast cancer between 2008 and 2014. We compared the three groups of patients who were divided based on the following surgeries: breast-conserving surgery (BCS), mastectomy, and mastectomy with IBR. RESULTS: Of the 3295 patients who were treated with neoadjuvant chemotherapy, 482 patients achieved a pathological complete response (pCR) and 2813 patients did not (non-pCR). In survival analysis of the pCR patients, the 5-year Overall Survival (5 yr OS) between those who underwent mastectomy with IBR and mastectomy (P = 0.639) In the non-pCR group, 5 yr OS of the mastectomy with IBR group was 90.0%, while those of the mastectomy group was 84.4% in patients with clinical stage II (P = 0.032). In a multivariate analysis by Cox regression method revealed that the prognoses of the patients who underwent mastectomy with IBR were not different from those of patients who underwent mastectomy group in both groups (the pCR group and the non-pCR group). CONCLUSION: In the pCR group, the prognoses of patients who underwent mastectomy with IBR were not different from those of patients who underwent mastectomy. In the non-pCR group, women in the mastectomy with IBR group had shown worse prognoses than the mastectomy group in advanced clinical stage. Appropriate operation should be determined depending on the status of individualized patients.