在美国,皮肤鳞状细胞癌(cSCC)占非黑色素瘤皮肤癌病例的20%。总的来说,3%至5%的鳞状细胞癌(SCC)在出现时转移,与由于缺乏标准化治疗方案而导致的显著死亡率相关。总的来说,这些肿瘤中有95%符合最初的治疗标准,也就是手术切除.然而,其中一小部分患者需要全身治疗,因为它们要么局部进展到局部淋巴结,要么有远处转移。出现cSCC的常见部位是头皮和面部,可预测扩散到腮腺内,颈上静脉,和面周淋巴结.在我们的案例报告中,然而,我们的病人在上背部有一个大的肿块病变,一个不寻常的cSCC出现地点,左腋窝淋巴结局部晚期转移。随后,肿瘤标志物研究显示SMARCA4变异体(Switch(SWI)/蔗糖非发酵(SNF)染色质-重塑复合物的必需ATP酶亚基)阳性,在cSCC中更为罕见.此外,作为免疫检查点抑制剂(ICI)治疗的靶向治疗,SWI/SNF染色质-重塑复合物亚基的异常显示出有希望的结果.我们提出了在初次手术切除后接受放化疗和ICI全身治疗的患者中局部晚期罕见变异SMARCA4阳性cSCC的非典型表现部位。迄今为止,文献中仅发现2例SMARCA4阳性cSCC,但未提供治疗细节.我们的病例在其非典型表现部位以及对放射疗法(RT)和ICI全身治疗的部分反应方面是独特的。
Cutaneous squamous cell carcinoma (cSCC) comprises 20% of cases of nonmelanoma skin cancers in the United States. In total, 3% to 5% of squamous cell carcinoma (SCC) are metastatic at the time of presentation, associated with significant mortality due to a lack of standardized treatment options. In total, 95% of these tumors are amenable to the initial standard of treatment, which is surgical resection. However, a small percentage of them require systemic therapy as they are either locally advanced to regional lymph nodes or have distant metastasis. The common sites of presentation of cSCC are the scalp and the face with predictable spread to the intra-parotid, upper jugular, and perifacial lymph nodes. In our
case report, however, our patient had a large lump lesion on the upper back, an unusual site of presentation of cSCC, with locally advanced metastasis to the left axillary lymph nodes. Subsequently, the tumor marker study revealed a positive SMARCA4 variant (the essential ATPase subunit of the Switch (SWI)/Sucrose Nonfermenting (SNF) chromatin-remodeling complex) that is even rarer in the context of cSCC. Furthermore, abnormalities in SWI/SNF chromatin-remodeling complex subunits have shown promising results as a target therapy for immune checkpoint inhibitor (ICI) therapy. We present an atypical presentation site of locally advanced rare variant SMARCA4-positive cSCC in a patient who received treatment with chemoradiation and systemic therapy with ICI after primary surgical resection. To date, only 2 cases of SMARCA4-positive cSCC were found in the literature with no details of the treatment received. Our
case is unique in its atypical site of presentation as well as showing partial response to radiotherapy (RT) and systemic therapy with ICI.