Supplementary Material for: Pancreatic adenocarcinoma with co-occurrence of KRAS and EGFR mutations, case report and literature review

Introduction: Mutation in KRAS (Kristin ras sarcoma virus) oncogene is the main driver in pancreatic ductal adenocarcinoma (PDAC) and is present in nearly 90% of patients with PDAC. EGFR (epidermal growth factor receptor) mutation is rare in PDAC and is mostly present in the absence of KRAS mutation. Co-occurrence of KRAS and EGFR mutations is extremely rare, and the value of EGFR inhibition in these cases is unknown. Case Presentation: Here we present a case of metastatic PDAC with co-occurrence of KRAS G12V and EGFR L730R. Despite primary resistance to FOLFIRINOX (folinic acid, fluorouracil, irinotecan, oxaliplatin) and Gemcitabine/nab-paclitaxel, this patient had biochemical response (decrease in carbohydrate antigen (CA) 19-9), and disease control of seven months on Gemcitabine/Erlotinib (an EGFR inhibitor). This response is remarkable in the late-line PDAC treatment setting and is unusual after progression of the tumor on Gemcitabine/nab-paclitaxel chemotherapy. Conclusion: This case suggests that Gemcitabine/Erlotinib could be an effective treatment in patients with PDAC and co-occurrence of EGFR and KRAS mutations.

引言：KRAS（Kristin ras肉瘤病毒癌基因）突变是胰腺导管腺癌（pancreatic ductal adenocarcinoma, PDAC）的主要驱动因素，近90%的胰腺导管腺癌患者存在该突变。表皮生长因子受体（epidermal growth factor receptor, EGFR）突变在胰腺导管腺癌中较为罕见，且大多发生在无KRAS突变的病例中。KRAS与EGFR突变共存的情况极为少见，此类患者接受EGFR抑制剂治疗的价值尚不明确。病例报告：本文报告1例合并KRAS G12V与EGFR L730R突变的转移性胰腺导管腺癌病例。该患者对FOLFIRINOX（亚叶酸钙、氟尿嘧啶、伊立替康、奥沙利铂）联合方案及吉西他滨/白蛋白结合型紫杉醇（nab-paclitaxel）治疗均存在原发耐药，但在接受吉西他滨/厄洛替尼（一种EGFR抑制剂）治疗后，出现了生化应答（糖类抗原19-9（carbohydrate antigen 19-9, CA19-9）水平下降），且疾病控制时长达到7个月。该应答在晚期胰腺导管腺癌治疗场景中极为显著，且在肿瘤对吉西他滨/白蛋白结合型紫杉醇化疗进展后出现这种应答实属罕见。结论：本病例提示，对于同时存在EGFR与KRAS突变的胰腺导管腺癌患者，吉西他滨/厄洛替尼可能是一种有效的治疗方案。