Background/Objectives: Breast cancer remains a significant global health concern, with HER2-positive metastatic breast cancer continuing to present persistent challenges despite advancements in targeted therapies, including trastuzumab deruxtecan (T-DXd). This study aimed to verify the impact of body composition changes on treatment-related toxicities, dose modifications, and clinical outcomes in patients receiving T-DXd. Methods: A retrospective analysis on 35 patients with HER2-positive metastatic breast cancer was conducted, analyzing body composition parameters such as subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), skeletal muscle area (SMA), and skeletal muscle index (SMI)—assessed using CT scans at baseline (T0) and after a median follow-up of 4 months (T1)—and calculating ΔT0–T1% of each parameter. Results: Significant reductions over time were observed in SAT (mean ΔSAT% = −5.7%,p= 0.023) and SMA (mean ΔSMA% = −4.9%,p= 0.001). Treatment-related adverse events (AEs) were common, with 31% of patients experiencing severe (Grade 3–4) toxicities. Patients with higher ΔSAT% (above the median value) experienced Grade 3–4 toxicities more frequently compared to those with lower ΔSAT% (below the median) (p< 0.05). Among patients without toxicities, a significant decrease in SAT was observed between T0 and T1 (p= 0.003), while no significant change was detected in patients with Grade 3–4 toxicities (p= 0.929). Greater reductions in SMA were associated with increased rates of treatment discontinuation (75% vs. 29%,p= 0.009). Kaplan–Meier analysis confirmed that greater reductions in SMA significantly increased the risk of mortality (HR 5.1, 95% CI: 1.05–24.79;p= 0.025) and showed a trend toward higher risk of disease progression (HR 2.58, 95% CI: 0.89–7.49;p= 0.063). Conclusions: Changes in body composition, particularly reductions in SMA, were associated with increased treatment discontinuation and mortality in HER2-positive metastatic breast cancer receiving T-DXd. Increase in SAT was associated with higher rates of severe toxicities, highlighting its potential role in predicting treatment-related complications, and the clinical relevance of nutritional changes on outcomes in this setting.
背景/目的：乳腺癌仍是全球重大健康问题，尽管包括德曲妥珠单抗（T-DXd）在内的靶向治疗取得进展，HER2阳性转移性乳腺癌仍持续带来严峻挑战。本研究旨在验证接受T-DXd治疗患者身体成分变化对治疗相关毒性、剂量调整及临床结局的影响。方法：对35例HER2阳性转移性乳腺癌患者进行回顾性分析，通过基线期（T0）及中位随访4个月（T1）的CT扫描评估皮下脂肪组织（SAT）、内脏脂肪组织（VAT）、骨骼肌面积（SMA）和骨骼肌指数（SMI）等身体成分参数，并计算各参数的ΔT0–T1%变化率。结果：随时间推移观察到SAT（平均ΔSAT% = −5.7%，p=0.023）和SMA（平均ΔSMA% = −4.9%，p=0.001）显著下降。治疗相关不良事件（AEs）常见，31%患者出现严重（3-4级）毒性。与ΔSAT%较低（低于中位数）的患者相比，ΔSAT%较高（高于中位数）的患者更频繁发生3-4级毒性（p<0.05）。在未出现毒性的患者中，T0至T1期间SAT显著下降（p=0.003），而3-4级毒性患者中未检测到显著变化（p=0.929）。SMA下降幅度越大，治疗中止率越高（75% vs. 29%，p=0.009）。Kaplan-Meier分析证实SMA的更大降幅显著增加死亡风险（HR 5.1，95% CI：1.05–24.79；p=0.025），并显示疾病进展风险升高趋势（HR 2.58，95% CI：0.89–7.49；p=0.063）。结论：身体成分变化（特别是SMA下降）与接受T-DXd治疗的HER2阳性转移性乳腺癌患者治疗中止率及死亡率增加相关。SAT增加与严重毒性发生率升高相关，凸显其在预测治疗相关并发症中的潜在作用，以及营养变化在此背景下对临床结局的重要意义。
肿瘤(癌症)患者之家