Rare histological subtypes of breast cancer introduce unique challenges to treatment and require a more personalized approach. Subtypes with favorable prognoses, such as mucinous, tubular, and cribriform carcinomas, generally respond well to less aggressive treatments such as endocrine therapy. However, certain triple-negative breast cancer subtypes that are typically considered aggressive also demonstrate unexpectedly better outcomes in specific cases. Conversely, more aggressive subtypes, including invasive micropapillary carcinoma and high-grade metaplastic breast cancer, often present greater treatment challenges due to their resistance to conventional therapies. Recent advancements in targeted treatments, such as immune checkpoint inhibitors, have shown promise in improving outcomes in some of these difficult cases. This review emphasizes the need for ongoing research and a tailored approach that considers both molecular and histological characteristics to improve the management and survival outcomes of patients with these rare and complex breast cancer subtypes.

Pleomorphic lobular carcinoma in situ (PLCIS) is a relatively uncommon subtype of lobular neoplasia, characterized by large pleomorphic discohesive cells exhibiting marked nuclear atypia, frequent central comedo-necrosis, and microcalcifications. Owing to these features, PLCIS is difficult to distinguish using radiological and histological analyses with high-grade ductal carcinoma in situ. This report presents a case in which breast PLCIS was initially misdiagnosed as invasive ductal carcinoma based on core-needle biopsy and radiological findings. However, further investigation confirmed the diagnosis of PLCIS with invasive lobular carcinoma, measuring only 1.04 mm. This case illustrates the diagnostic challenges of PLCIS, which mimics invasive ductal carcinoma, causing unnecessarily aggressive treatment. Notably, this warrants careful pathological and radiological evaluations for accurate diagnosis and guides appropriate management.

Rare histological subtypes of breast cancer introduce unique challenges to treatment and require a more personalized approach. Subtypes with favorable prognoses, such as mucinous, tubular, and cribriform carcinomas, generally respond well to less aggressive treatments such as endocrine therapy. However, certain triple-negative breast cancer subtypes that are typically considered aggressive also demonstrate unexpectedly better outcomes in specific cases. Conversely, more aggressive subtypes, including invasive micropapillary carcinoma and high-grade metaplastic breast cancer, often present greater treatment challenges due to their resistance to conventional therapies. Recent advancements in targeted treatments, such as immune checkpoint inhibitors, have shown promise in improving outcomes in some of these difficult cases. This review emphasizes the need for ongoing research and a tailored approach that considers both molecular and histological characteristics to improve the management and survival outcomes of patients with these rare and complex breast cancer subtypes.

Pleomorphic lobular carcinoma in situ (PLCIS) is a relatively uncommon subtype of lobular neoplasia, characterized by large pleomorphic discohesive cells exhibiting marked nuclear atypia, frequent central comedo-necrosis, and microcalcifications. Owing to these features, PLCIS is difficult to distinguish using radiological and histological analyses with high-grade ductal carcinoma in situ. This report presents a case in which breast PLCIS was initially misdiagnosed as invasive ductal carcinoma based on core-needle biopsy and radiological findings. However, further investigation confirmed the diagnosis of PLCIS with invasive lobular carcinoma, measuring only 1.04 mm. This case illustrates the diagnostic challenges of PLCIS, which mimics invasive ductal carcinoma, causing unnecessarily aggressive treatment. Notably, this warrants careful pathological and radiological evaluations for accurate diagnosis and guides appropriate management.

Rare histological subtypes of breast cancer introduce unique challenges to treatment and require a more personalized approach. Subtypes with favorable prognoses, such as mucinous, tubular, and cribriform carcinomas, generally respond well to less aggressive treatments such as endocrine therapy. However, certain triple-negative breast cancer subtypes that are typically considered aggressive also demonstrate unexpectedly better outcomes in specific cases. Conversely, more aggressive subtypes, including invasive micropapillary carcinoma and high-grade metaplastic breast cancer, often present greater treatment challenges due to their resistance to conventional therapies. Recent advancements in targeted treatments, such as immune checkpoint inhibitors, have shown promise in improving outcomes in some of these difficult cases. This review emphasizes the need for ongoing research and a tailored approach that considers both molecular and histological characteristics to improve the management and survival outcomes of patients with these rare and complex breast cancer subtypes.

Pleomorphic lobular carcinoma in situ (PLCIS) is a relatively uncommon subtype of lobular neoplasia, characterized by large pleomorphic discohesive cells exhibiting marked nuclear atypia, frequent central comedo-necrosis, and microcalcifications. Owing to these features, PLCIS is difficult to distinguish using radiological and histological analyses with high-grade ductal carcinoma in situ. This report presents a case in which breast PLCIS was initially misdiagnosed as invasive ductal carcinoma based on core-needle biopsy and radiological findings. However, further investigation confirmed the diagnosis of PLCIS with invasive lobular carcinoma, measuring only 1.04 mm. This case illustrates the diagnostic challenges of PLCIS, which mimics invasive ductal carcinoma, causing unnecessarily aggressive treatment. Notably, this warrants careful pathological and radiological evaluations for accurate diagnosis and guides appropriate management.

Locoregional recurrence (LRR) in breast cancer poses significant challenges due to its association with biologically resistant disease and a high likelihood of concurrent occult systemic disease. Despite advancements in local and systemic therapies, LRR affects a substantial percentage of patients, leading to poorer prognosis compared to those with primary breast cancer. Therefore, a comprehensive review of systemic treatment strategies following LRR is warranted to address the gaps in our understanding and improve patient outcomes. This review explored factors influencing the prognosis of breast cancer LRR. In particular, we evaluated the benefits of systemic treatment options post-resection and proposed an optimal treatment algorithm.

Granular cell tumor is a rare disease, and it is even rarer in the male breast. Although it is typically a benign tumor, due to its features and image findings, it can be easily misdiagnosed and managed as a malignant tumor. Therefore, the extent of the surgery can inappropriately be expanded. To avoid misdiagnosis and overtreatment, surgeons must perform a careful evaluation. We describe a case of a granular cell tumor of the male breast treated with mastectomy.

As breast-conserving surgery (BCS) has become the most common type of breast surgery, oncoplastic BCS has developed in response to improve cosmetic outcomes. Acellular dermal matrix (ADM) has been used as an adjunct to enhance cosmetic outcomes in partial breast reconstruction. This study aimed to evaluate postoperative complications, cosmetic satisfaction, and oncologic safety over a short-term follow-up period. Methods: This retrospective study included 26 patients who underwent BCS at Myongji Hospital between April 2019 and April 2021. All procedures were performed by three surgeons. We reviewed demographic data, histologic grades, tumor-node-metastasis stages, treatment modalities, and survival data based on patient medical records. Results: Of the 26 total patients, 5 developed seromas, which was the most common complication, and one patient experienced red breast syndrome. The incidence of complications per surgeon was less than 25%. The mean satisfaction score for the cosmetic outcome on a 10-point scale was 7.6 ( ± 2.1) as scored by patients and 8.8 ( ± 0.9) as scored by surgeons. Responses regarding cosmetic satisfaction revealed no significant differences among surgeons (p= 0.444). Of the 26 patients, four were lost to follow-up, and the mean follow-up period was 35.2 months. Two patients experienced recurrence, both of whom had regional recurrence with no local recurrence. Conclusion: ADM replacement is a favorable alternative to oncoplastic BCS, in terms of the ease of surgical procedures, minimal complications, and low rates of local recurrence.

Purpose: The standard care for patients with ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS) is a total mastectomy (TM); however, there is growing interest in repeating BCS for IBTR. Methods: We retrospectively analyzed patients with IBTR who underwent initial BCS for breast cancer at our institution between January 2000 and December 2018. The Kaplan-Meier method was used to compare survival rates between the standard BCS-TM treatment group and the repeat-BCS group. Results: We enrolled 209 IBTR patients with a median follow-up of 102.3 months. No significant differences were observed in overall survival (10 years: 87.3% vs. 78.8%; hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.44-2.81; p=0.821), distant metastasis free survival (10 years: 73.9% vs. 77.7%; HR, 0.80; 95% CI, 0.37-1.72; p=0.727) and disease-free survival (10 years: 57.1% vs. 65.2%; HR, 0.63; 95% CI, 0.35-1.12; p=0.115) between two groups. Repeat-BCS group showed significantly poorer locoregional recurrence free survival rate than did the TM group (HR, 2.44; 95% CI, 1.06-5.56; p=0.029) but the significance was not shown after excluding ipsilateral breast tumor recurrence events. Conclusion No significant differences were observed in survival outcomes and recurrence rates between patients with IBTR who underwent mastectomy or repeat BCS regardless of molecular subtype, except secondary IBTR rates.