Background/Objectives: Anal cancer is a rare malignancy with limited treatment options. Immune checkpoint inhibitors have shown benefits in some patients with metastatic disease, but predictive factors for immunotherapy response remain undefined. This study retrospectively evaluated clinical and pathological features associated with survival outcomes in metastatic anal cancer treated with immunotherapy.Methods: Data from 105 patients with metastatic anal cancer were analyzed. Kaplan–Meier analysis was used to estimate progression-free survival (PFS) and overall survival (OS), with subgroup comparisons utilizing the Mantel–Cox test. Associations between survival and clinicopathologic features were assessed with Fisher’s exact test.Results: Of the patients, 69 (65.7%) received immunotherapy during the first three treatment lines. With a median follow-up of 23.2 months, the median PFS for first-, second-, and third-line systemic therapies was 7.2, 3.7, and 4.7 months, respectively (χ2= 14.2;p< 0.001). In the treatment-refractory setting, median PFS was similar for immunotherapy and chemotherapy: 3.6 months (95% CI, 2.3–4.9) vs. 4.4 months (95% CI, 3.8–5.0), respectively (HR 0.89, 95% CI 0.60–1.3;p= 0.52). Among patients treated with immunotherapy, patients with lymph node-only metastases had significantly prolonged PFS compared to patients with visceral organ involvement (11.3 vs. 3.1 months; HR 0.49, 95% CI 0.21–0.74;p= 0.03).Conclusions: Patients with lymph node-only metastatic anal cancer experienced significantly prolonged PFS with immunotherapy relative to those with involvement of other distant organs, highlighting a distinct subgroup of patients who may benefit from immunotherapy. We also contextualize PFS outcomes across treatment lines for metastatic anal cancer, which can be applied towards the design of future immunotherapy clinical trials.
背景/目的：肛门癌是一种罕见恶性肿瘤，治疗选择有限。免疫检查点抑制剂已在部分转移性患者中显示出疗效，但免疫治疗反应的预测因素尚未明确。本研究回顾性评估了接受免疫治疗的转移性肛门癌患者临床病理特征与生存结局的关联性。 方法：分析105例转移性肛门癌患者数据。采用Kaplan-Meier法评估无进展生存期（PFS）和总生存期（OS），亚组比较使用Mantel-Cox检验。通过Fisher精确检验评估生存期与临床病理特征的关联。 结果：患者中69例（65.7%）在前三线治疗期间接受了免疫治疗。中位随访23.2个月，一线、二线和三线全身治疗的中位PFS分别为7.2、3.7和4.7个月（χ²=14.2；p<0.001）。在难治性治疗背景下，免疫治疗与化疗的中位PFS相近：分别为3.6个月（95% CI 2.3-4.9）和4.4个月（95% CI 3.8-5.0）（HR 0.89，95% CI 0.60-1.3；p=0.52）。在接受免疫治疗的患者中，仅淋巴结转移患者的PFS较内脏器官受累患者显著延长（11.3个月 vs 3.1个月；HR 0.49，95% CI 0.21-0.74；p=0.03）。 结论：与其他远处器官受累患者相比，仅淋巴结转移的肛门癌患者接受免疫治疗后PFS显著延长，这提示存在可能从免疫治疗中获益的特殊亚群。本研究还系统阐述了转移性肛门癌各线治疗的PFS结局，可为未来免疫治疗临床试验设计提供参考。
肿瘤(癌症)患者之家