School of Public Health, Guangdong Medical University, Dongguan, China.
Department of Dermatology, Guangdong Medical Affiliated Hospital, Zhanjiang, China.
Biomol Biomed. 2024 Jan 10;24(4):959-967. doi: 10.17305/bb.2023.10029.
Radiation therapy (RT), a primary treatment for breast cancer (BC), may be associated with increased non-BC tumor risk. We aimed to examine second cutaneous melanoma (SCM) risk in BC patients who underwent RT and to assess their survival outcomes. Data from 520,977 BC patients diagnosed between 1973-2018 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Cumulative SCM incidence was estimated using the Fine-Gray competing risk model. Poisson regression analysis was conducted to calculate the standardized incidence ratio (SIR) and estimate the SCM relative risk in patients who underwent RT compared to those who did not. Overall survival (OS) and cancer-specific survival (CSS) were assessed using the Kaplan‒Meier method. Among the 520,977 BC patients, 243,676 (46.8%) underwent surgery and RT, while 277,301 (53.2%) only underwent surgery. Our results suggest that BC patients receiving RT had a higher SCM risk than those who did not (hazard ratio [HR] 1.40; 95% confidence interval [CI] 1.30-1.51; P < 0.001). SCM incidence was also higher in BC patients treated with RT than in the general US population (SIR 1.12; 95% CI 1.05-1.19; P < 0.05). However, SCM patients who received RT had a significantly higher 10-year survival rate than those who did not receive RT (14.90% vs 5.94%; P < 0.001). No significant difference was found in 10-year OS or 5-year CSS between SCM following RT and only primary cutaneous melanoma (OPCM), but SCM patients who did not receive RT had a significantly lower 10-year OS, with no significant difference in CSS. This study suggests an increased SCM likelihood in BC patients due to RT, although the overall risk is minimal.
放射治疗（RT）是乳腺癌（BC）的主要治疗方法之一，但可能会增加非 BC 肿瘤的风险。我们旨在研究接受 RT 的 BC 患者第二皮肤黑色素瘤（SCM）的风险，并评估他们的生存结果。这项研究的数据来自于 1973 年至 2018 年间诊断的 520977 名 BC 患者，这些数据来自监测、流行病学和最终结果（SEER）数据库。使用 Fine-Gray 竞争风险模型估计累积 SCM 发病率。采用泊松回归分析计算接受 RT 与未接受 RT 的患者的标准化发病率比（SIR）和 SCM 相对风险。采用 Kaplan-Meier 方法评估总生存期（OS）和癌症特异性生存期（CSS）。在 520977 名 BC 患者中，243676 名（46.8%）接受了手术和 RT，而 277301 名（53.2%）仅接受了手术。结果表明，接受 RT 的 BC 患者的 SCM 风险高于未接受 RT 的患者（风险比 [HR] 1.40；95%置信区间 [CI] 1.30-1.51；P < 0.001）。与一般美国人群相比，接受 RT 的 BC 患者的 SCM 发病率也更高（SIR 1.12；95%CI 1.05-1.19；P < 0.05）。然而，接受 RT 的 SCM 患者的 10 年生存率显著高于未接受 RT 的患者（14.90%比 5.94%；P < 0.001）。在 RT 后 SCM 与原发性皮肤黑色素瘤（OPCM）之间，10 年 OS 或 5 年 CSS 无显著差异，但未接受 RT 的 SCM 患者的 10 年 OS 显著较低，CSS 无显著差异。本研究表明，BC 患者因 RT 而增加了 SCM 的可能性，尽管总体风险很小。
