Survival After Development of Contralateral Breast Cancer in Korean Patients With Breast Cancer.

Importance: Contralateral breast cancer (CBC) is the most frequently diagnosed primary cancer in patients with breast cancer. Although many studies have reported survival after the development of CBC, results have been inconsistent. Objective: To investigate whether the development of CBC is associated with survival among patients with breast cancer. Design, Setting, and Participants: This cohort study was conducted at the Asan Medical Center, Korea, among patients who were diagnosed with primary unilateral, nonmetastatic, stage 0 to III breast cancer between 1999 and 2013 and followed up through 2018. The median (IQR) follow-up was 107 (75-143) months. Patients were categorized into CBC and no-CBC groups by whether they developed CBC during the follow-up period. Data were analyzed from November 2021 to March 2023. Exposure: Development of CBC. Main outcomes and measures: Survival rates of CBC and no-CBC groups were compared using a time-dependent Cox proportional hazard model in the entire study population and in subgroup analyses by interval of CBC development and subtype of the primary breast cancer. Results: Among 16 251 patients with breast cancer (all Asian, specifically Korean; mean [SD] age, 48.61 [10.06] years), 418 patients developed CBC. There was no significant difference in overall survival between CBC and no-CBC groups (hazard ratio, 1.166; 95% CI, 0.820-1.657). Patients who developed CBC within 1.5 years after the surgery of the primary breast cancer had a higher risk for overall death during the study period (hazard ratio, 2.014; 95% CI, 1.044-3.886), and those who developed CBC after 1.5 years showed no significant difference in survival compared with the no-CBC group. Patients with hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (ERBB2, formerly HER2)-negative breast cancer had a higher risk for overall death in the CBC group (hazard ratio, 1.882; 95% CI, 1.143-3.098) compared with the no-CBC group. Conclusions and Relevance: This study found that development of CBC in patients with breast cancer was not associated with survival but that early development of CBC after diagnosis of the primary breast cancer or development of CBC in patients with HR-positive/ERBB2-negative breast cancer was associated with survival. These results may provide valuable information for patients seeking advice on opting for contralateral prophylactic mastectomy.

Factors associated with upgrade, malignant upgrade, and subsequent breast cancer occurrence of papillary breast lesions diagnosed on core needle biopsy.

AIM: In this study, we analyzed the upgrade rate and associated factors for upgrade, malignant upgrade, and subsequent breast cancer occurrence of papillary breast lesions diagnosed on core needle biopsy (CNB). METHODS: One hundred sixty-nine patients who underwent surgery for the treatment of papillary breast lesions diagnosed on CNB were included in this study. Medical records including radiological and pathological reports were retrospectively reviewed. RESULTS: The overall upgrade rate was 29.6%, and upgrade rate to malignancy was 16.6%. Age over 45 years, preoperative tumor size ≥0.7 cm on breast ultrasound, pathologic tumor size ≥0.4 cm, breast imaging reporting and data system (BIRADS) category 4b or 4c, and personal history of breast cancer were associated with upgrade. In addition, age over 45 years, preoperative tumor size ≥0.9 cm, pathologic tumor size ≥0.6 cm, atypia in CNB, and BIRADS category 4b or 4c were associated with malignancy. The risk of subsequent breast cancer occurrence was increased in preoperative tumor size ≥0.8 cm, pathologic tumor size ≥0.5 cm, multiple and recurrent lesions. CONCLUSION: Our study showed high upgrade rate of papillary breast lesions diagnosed on CNB. Our findings suggest that surgical excision is recommended for papillary breast lesions diagnosed on CNB in selected patients.

Do very young Korean breast cancer patients have worse outcomes?

BACKGROUND: In general, Korean women with breast cancer are younger than white women. We have compared the clinicopathologic characteristics and prognosis in very young and less young premenopausal Korean women with breast cancer. METHODS: Of the breast cancer patients treated at the Asan Medical Center in Seoul, Korea, from 1989 to 2002, 381 (9.6%) were younger than 35 years of age (the "very young" group) and 2320 were 35 to 50 years of age (the "less young" group). We retrospectively compared the clinicopathologic factors and survival rates of these two groups. RESULTS: The very young group with lymph node metastases had poorer 5-year survival (69.9% vs. 82.7%, P = .0063) and disease-free survival (58.1% vs. 74.1%, P < .0001) rates than their older counterparts. In addition, the very young group had more advanced-stage disease (P = .001), higher T stage (P = .001), and more positive lymph nodes (P = .024) than did their older counterparts, as well as higher percentages of estrogen receptor-negative disease (48.2% vs. 42.1%, P = .047), progesterone receptor-negative disease (53.5% vs. 44.1%, P = .002), and grade 3 histology (52.1% vs. 43.5%, P = .011) tumors. CONCLUSIONS: Compared with older premenopausal Korean women with breast cancer, those younger than 35 years old had a poorer prognosis as a result of a higher rate of recurrence, a later stage at diagnosis, and more aggressive disease. Thus, in Korean breast cancer patients, age younger than 35 years was an independent predictor of recurrence.

Changing patterns in the clinical characteristics of Korean patients with breast cancer during the last 15 years.

HYPOTHESIS: Breast cancer has become the most common cancer in Korean women in recent years, with continuously increased incidence rates attributed to westernized lifestyles. DESIGN: Retrospective case series evaluating the changing patterns of clinical characteristics in breast cancer during the last 15 years. SETTING: Hospitalized patients with breast cancer in a university medical center. PATIENTS: A total of 5001 breast cancer patients who underwent surgery between July 1989 and March 2004 at the Asan Medical Center. MAIN OUTCOME MEASURE: Clinicopathologic data were collected using the online Korea Breast Cancer Registration Program, including factors such as age, symptoms, stage, surgery, reconstruction, risk factors, and survival. RESULTS: The median age of patients slightly increased from 44 years in 1991 to 46 years in 2003. The most frequent age group was the fifth decade (41.7%) and premenopausal women younger than 50 years (64.9%). The proportion of asymptomatic patients detected by screening mammography increased from 3.8% in 1991 to 21.0% in 2003 (P<.001). The proportion of early breast cancer (stages 0 and I) increased from 34.2% in 1991 to 48.8% in 2003 (P=.013). Breast-conserving surgery has increased continuously from 5.1% in 1991 to 39.1% in 2003 (P<.001). Twelve percent of all patients who underwent mastectomies had immediate reconstruction, and the proportion showed an increasing trend, especially in skin-sparing mastectomy and transverse rectus abdominis myocutaneous flap reconstruction. Five-year observed survival rates were 84.1%. Five-year survival rates according to stages were as follows: (1) 98.5%, stage 0; (2) 95.3%, stage I; (3) 86.0%, stage II; (4) 65.0%, stage III; and (5) 29.3%, stage IV. The number of patients with specific risk factors, such as early menarche and late first delivery, significantly increased. Of 263 high-risk patients examined for the BRCA mutation, mutations were found in 20 patients (7.6%), with 13 cases with BRCA1 and 7 cases with BRCA2. CONCLUSIONS: The present study showed a continuous increase in the number of patients with breast cancer; the proportion of young patients, asymptomatic patients, early breast cancer, breast-conserving surgery, and immediate reconstruction after mastectomy; and the number of patients with risk factors. These results suggest that the clinical characteristics of Korean breast cancer patients reflect the patterns of Western countries.