Department of Surgery, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Republic of Korea.
Biostatistics Collaboration Team, Research Core Center, Research Institute of National Cancer Center, Goyang, Republic of Korea.
Cancer Med. 2024 Oct;13(19):e70297. doi: 10.1002/cam4.70297.
The prognosis of microinvasive breast cancer (MIBC) is controversial, with a high reported rate of local recurrence (LR). This study aimed to evaluate the characteristics, treatments, and prognosis of patients with MIBC compared to those with carcinoma in situ (CIS) or early invasive cancer.
Patients who diagnosed with CIS or stage I breast cancer were retrospectively enrolled. Using the Kaplan-Meier method, local recurrence-free survival (LRFS), systemic recurrence-free survival (SRFS), and cancer-specific survival (CSS) were compared according to T stage. The prognostic factors associated with LRFS were identified using the Cox proportional hazards model.
According to T stage, 517 (21.6%), 200 (8.4%), 207 (8.7%), 363 (15.2%), and 1101 (46.1%) patients had Tis, T1mi, T1a, T1b, and T1c tumors, respectively. The proportion of human epidermal growth factor receptor 2-positive tumors was significantly higher in patients with MIBC (p < 0.0001). The administered adjuvant treatments also showed differences according to T stage (p < 0.0001). During the 73-month median follow-up period, patients with MIBC showed significantly worse LRFS than those with T1a or T1c tumors (p = 0.002). There was no significant difference in SRFS and CSS. In the Cox regression analysis, tumor multiplicity (p = 0.017), Ki-67 (p = 0.025), cancer subtype (p = 0.034), adjuvant endocrine therapy (p = 0.003), and adjuvant radiation therapy (p < 0.0001) were significant prognostic factors associated with LRFS.
The risk of LR was higher in patients with MIBC than in those with small invasive breast cancer. Therefore, if indicated, adjuvant endocrine and radiation therapies should be administered to prevent undertreatment in patients with MIBC.
微浸润性乳腺癌（MIBC）的预后存在争议，局部复发率（LR）报道较高。本研究旨在评估 MIBC 患者与癌前原位（CIS）或早期浸润性癌患者的特征、治疗方法和预后。
回顾性纳入诊断为 CIS 或 I 期乳腺癌的患者。使用 Kaplan-Meier 法，根据 T 分期比较局部无复发生存率（LRFS）、系统无复发生存率（SRFS）和癌症特异性生存（CSS）。使用 Cox 比例风险模型确定与 LRFS 相关的预后因素。
根据 T 分期，517（21.6%）、200（8.4%）、207（8.7%）、363（15.2%）和 1101（46.1%）例患者分别为Tis、T1mi、T1a、T1b 和 T1c 肿瘤。MIBC 患者中人类表皮生长因子受体 2 阳性肿瘤的比例显著更高（p<0.0001）。根据 T 分期，给予的辅助治疗也存在差异（p<0.0001）。在 73 个月的中位随访期间，MIBC 患者的 LRFS 明显差于 T1a 或 T1c 肿瘤患者（p=0.002）。SRFS 和 CSS 无显著差异。在 Cox 回归分析中，肿瘤多发性（p=0.017）、Ki-67（p=0.025）、癌症亚型（p=0.034）、辅助内分泌治疗（p=0.003）和辅助放疗（p<0.0001）是与 LRFS 相关的显著预后因素。
MIBC 患者的 LR 风险高于小浸润性乳腺癌患者。因此，如果需要，应给予 MIBC 患者辅助内分泌和放疗，以避免治疗不足。
