De novo metastatic breast cancer (dnMBC) accounts for 3–10% of newly diagnosed cases, with 20–40% presenting as a bone-only metastatic disease, which can achieve survival outcomes exceeding 10 years with multimodal therapy. However, the role of multimodal therapy remains controversial in the guidelines.Objective:This study aims to identify dnBOMBC subgroups to develop a pragmatic staging system for guiding locoregional therapy decisions.Materials and Methods:Data from the MF07-01 phase III randomized trial (2021, median follow-up time (mFT): 40 months (range 1–131)) and the BOMET prospective multi-institutional registry trial (2021, mFT: 34 months (range 25–45)) were combined for analysis, including only patients who presented with bone-only metastases. Exclusion criteria were patients under 18 and those with a history of prior cancer or cancer metastases. Patients with missing data and positive surgical margins were excluded. Out of 770 patients, 589 were included. Survival analyses were first conducted according to molecular subgroups, after which patients were further stratified by hormone receptor status, human epidermal human epidermal growth factor receptor 2 (HER2) status, tumor grade, and clinical T (cT) stage. Group A (GrA) included hormone receptor (HR)-positive, low- or intermediate-grade tumors at any cT; HR-positive, high-grade tumors with cT0–3; or any HER2-positive tumors. Group B (GrB) included HR-positive, high-grade tumors with cT4 disease or any triple-negative (TN) tumors.Results:The hazard of death (HoD) was 43% lower in GrA than in GrB. Median OS was 65 months (39–104) for GrA patients and 44 months (28–72) for GrB patients (HR 0.57, 95% CI 0.41–0.78,p= 0.0003). Primary tumor surgery (PTS) significantly improved OS in GrA patients, regardless of the number of metastases (solitary: HR, 0.375, 95% CI 0.259–0.543,p< 0.001; multiple: HR 0.435, 95% CI 0.334–0.615,p< 0.001). Conversely, GrB patients did not experience a significant benefit from PTS.Conclusions:This study demonstrates that GrA patients have better OS than GrB patients, and PTS reduces the HoD in GrA patients compared to systemic therapy alone. These findings support using a modified staging system in dnBOBMC to identify patients who may benefit from multimodal therapy including PTS.
初诊转移性乳腺癌（dnMBC）占新诊断病例的3-10%，其中20-40%表现为单纯骨转移，通过多模式治疗可获得超过10年的生存期。然而，多模式治疗在指南中的作用仍存在争议。 目的：本研究旨在识别dnBOMBC亚组，以建立指导局部区域治疗决策的实用分期系统。 材料与方法：结合MF07-01 III期随机试验（2021年，中位随访时间（mFT）：40个月（范围1-131））和BOMET前瞻性多机构注册试验（2021年，mFT：34个月（范围25-45））的数据进行分析，仅纳入表现为单纯骨转移的患者。排除标准包括年龄小于18岁、有既往癌症或癌症转移史的患者。数据缺失和手术切缘阳性的患者也被排除。在770例患者中，共纳入589例。首先根据分子亚组进行生存分析，随后根据激素受体状态、人表皮生长因子受体2（HER2）状态、肿瘤分级和临床T（cT）分期对患者进一步分层。A组（GrA）包括激素受体（HR）阳性、任何cT分期的低或中级别肿瘤；HR阳性、cT0-3的高级别肿瘤；或任何HER2阳性肿瘤。B组（GrB）包括HR阳性、cT4分期的高级别肿瘤或任何三阴性（TN）肿瘤。 结果：GrA组的死亡风险（HoD）比GrB组低43%。GrA患者的中位总生存期（OS）为65个月（39-104），GrB患者为44个月（28-72）（HR 0.57，95% CI 0.41-0.78，p=0.0003）。无论转移灶数量如何，原发肿瘤手术（PTS）均显著改善了GrA患者的OS（单发转移：HR 0.375，95% CI 0.259-0.543，p<0.001；多发转移：HR 0.435，95% CI 0.334-0.615，p<0.001）。相反，GrB患者未从PTS中获得显著益处。 结论：本研究表明，GrA患者的OS优于GrB患者，且与单纯全身治疗相比，PTS降低了GrA患者的死亡风险。这些发现支持在dnBOBMC中使用改良的分期系统，以识别可能从包括PTS在内的多模式治疗中获益的患者。
A Pragmatic Grouping Model for Bone-Only De Novo Metastatic Breast Cancer (MetS Protocol MF22-03)
肿瘤(癌症)患者之家