Department of Dermatologic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 1040045, Japan.
Department of Dermatology, Fukuoka University, 8-19-1, Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan.
J Cancer Res Clin Oncol. 2023 Feb;149(2):749-755. doi: 10.1007/s00432-022-03933-2. Epub 2022 Feb 3.
Primary anorectal melanoma (ARM) accounts for approximately 1.2% of all melanomas and 16.5% of all mucosal melanomas. ARM is associated with the shortest interval to disease progression and the highest rate of metastasis; however, optimal therapeutic strategies for ARM remain controversial. This study aimed to assess the ideal surgical intervention for ARM and to determine the effect of immune checkpoint inhibitors (ICI).
We included 47 patients with ARM treated at the National Cancer Center Hospital in Japan from 2011 to 2020. We performed a survival analysis for each of these groups: (i) patients with ARM (n = 47); (ii) operable non-stage IV cases at initial presentation (n = 35); and (iii) stage IV cases (n = 32).
The 5-year overall survival (OS) was 53.6%, and the median OS was 78.7 months in patients with ARM. No statistically significant difference in 5-year OS was found between rectal and anal sites (50.9% vs. 56.7%). In the non-stage IV subgroup, the type of surgery (abdominoperineal resection or wide local excision) did not correlate with OS (HR 1.85; 95% CI 0.46-7.5; p = 0.39). In the stage IV subgroup, the 2-year OS of the ICI treatment group was 61.4%, whereas that of the dacarbazine regimen group was 0% (p = 0.048).
Our ARM prognosis was better than that of previous studies. Our findings suggest that the availability of ICI therapy may improve survival in patients with advanced ARM. However, further research is warranted to identify both the clinical and molecular predictors of response to improve patient selection.
原发性肛门直肠黑色素瘤（ARM）约占所有黑色素瘤的 1.2%，占所有黏膜黑色素瘤的 16.5%。ARM 与疾病进展的间隔时间最短，转移率最高；然而，ARM 的最佳治疗策略仍存在争议。本研究旨在评估 ARM 的理想手术干预措施，并确定免疫检查点抑制剂（ICI）的效果。
我们纳入了 2011 年至 2020 年在日本国家癌症中心医院治疗的 47 例 ARM 患者。我们对这些组进行了生存分析：（i）ARM 患者（n=47）；（ii）初次就诊时可手术的非 IV 期病例（n=35）；和（iii）IV 期病例（n=32）。
ARM 患者的 5 年总生存率（OS）为 53.6%，中位 OS 为 78.7 个月。直肠和肛门部位的 5 年 OS 无统计学差异（50.9% vs. 56.7%）。在非 IV 期亚组中，手术类型（腹会阴切除术或广泛局部切除术）与 OS 无关（HR 1.85；95%CI 0.46-7.5；p=0.39）。在 IV 期亚组中，ICI 治疗组的 2 年 OS 为 61.4%，而达卡巴嗪方案组为 0%（p=0.048）。
我们的 ARM 预后优于以往的研究。我们的研究结果表明，ICI 治疗的应用可能改善晚期 ARM 患者的生存。然而，需要进一步的研究来确定对治疗反应的临床和分子预测因子，以改善患者的选择。
