Background Anal squamous cell carcinoma (ASCC) is a rare cancer with increased occurrence of multiple cancers before and after the ASCC diagnosis. However, there is limited data on this aspect. This multi-institutional analysis aimed to define the occurrence of malignancies before and after ASCC, time trends, impact on survival, and identify prognostic factors. Material and Methods Initial primary malignancy (IPM) was defined as a malignancy occurring before the ASCC. Second primary malignancy (SPM) was defined as a distinct primary cancer that developed after ASCC diagnosis. Retrospective multi-institutional chart review was done. Progression free survival (PFS), overall survival (OS) and prognostic factors were evaluated. Results 647 patients with ASCC treated with curative intent were analyzed. Median age was 61.23 years with 72% as females. 150 patients (23.3%) had multiple malignancies with IPM in 16% and SPM in 8%. Patients without prior cancer had better 5-year PFS (81.2% vs 67.2%, p = .011) and OS (81% vs 69%, p = .008) compared to those with prior cancer. SPMs had a significant adverse impact on PFS (HR 4.22) and OS (HR 3.56). Females had better 5-year PFS (82% vs 70%, p = .016) as compared to males. The median time interval for developing ASCC (as SPM) after IPM was 9.32 years. Conclusions ASCC patients have increased risk of multiple malignancies. Patients with prior cancer have inferior outcomes. SPM is a poor prognostic factor in patients without any prior cancer. SPM can develop years after treatment of primary ASCC.

中文翻译：

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肛门鳞状细胞癌放化疗前后恶性肿瘤发生率增加：多机构分析


背景 肛门鳞状细胞癌 （ASCC） 是一种罕见的癌症，在 ASCC 诊断前后多种癌症的发生率增加。但是，这方面的数据有限。这项多机构分析旨在定义 ASCC 前后恶性肿瘤的发生、时间趋势、对生存的影响，并确定预后因素。材料和方法 初始原发性恶性肿瘤 （IPM） 被定义为发生在 ASCC 之前的恶性肿瘤。第二原发性恶性肿瘤 （SPM） 被定义为 ASCC 诊断后发展的不同原发性癌症。进行了回顾性多机构图表审查。评估无进展生存期 （PFS） 、总生存期 （OS） 和预后因素。结果 分析 647 例以治愈为目的的 ASCC 患者。中位年龄为 61.23 岁，其中 72% 为女性。150 例患者 （23.3%） 患有多发性恶性肿瘤，其中 IPM 占 16%，SPM 占 8%。与既往癌症患者相比，既往无癌症的患者 5 年 PFS （81.2% vs 67.2%，p = .011） 和 OS （81% vs 69%，p = .008） 更好。SPMs 对 PFS （HR 4.22） 和 OS （HR 3.56） 有显著的不利影响。与男性相比，女性的 5 年 PFS 更好 （82% vs 70%，p = .016）。IPM 后发生 ASCC （作为 SPM） 的中位时间间隔为 9.32 年。结论 ASCC 患者多发性恶性肿瘤的风险增加。既往患有癌症的患者预后较差。SPM 是既往无任何癌症患者的不良预后因素。SPM 可在原发性 ASCC 治疗后数年发展。