Abstract：
BACKGROUND: Immune checkpoint inhibitors (ICIs) are attracting increasing attention as a novel and potentially curative therapy for microsatellite instability-high (MSI-H) colorectal cancer (CRC).
METHODS: An 80-year-old female visited our hospital with complaints of lower abdominal pain due to bowel obstruction caused by descending colon cancer. After 1 month of metallic stent detention, she underwent radical surgery, although laparotomy showed broad peritoneal dissemination. Based on the genetic finding of MSI-H status, pembrolizumab therapy was administered in two cycles. Unfortunately, the therapy was ineffective, and the patient died after being discharged 5 months after surgery.
CONCLUSIONS: The findings in this case of MSI-H CRC with a poor response to an ICI suggest the importance of confirming HLA status, including beta-2-microglobulin and HLA expression, before starting ICI therapy in cases of MSI-H CRC.
METHODS: An 80-year-old female visited our hospital with complaints of lower abdominal pain due to bowel obstruction caused by descending colon cancer. After 1 month of metallic stent detention, she underwent radical surgery, although laparotomy showed broad peritoneal dissemination. Based on the genetic finding of MSI-H status, pembrolizumab therapy was administered in two cycles. Unfortunately, the therapy was ineffective, and the patient died after being discharged 5 months after surgery.
CONCLUSIONS: The findings in this case of MSI-H CRC with a poor response to an ICI suggest the importance of confirming HLA status, including beta-2-microglobulin and HLA expression, before starting ICI therapy in cases of MSI-H CRC.
摘要：
背景：免疫检查点抑制剂（ICIs）作为微卫星不稳定性高（MSI-H）结直肠癌（CRC）的新型且潜在的治愈性治疗方法，正引起越来越多的关注。
方法：一名80岁的女性到我院就诊，主诉降结肠癌引起的肠梗阻引起下腹痛。金属支架滞留1个月后,她接受了根治性手术,虽然剖腹手术显示广泛的腹膜播散。基于MSI-H状态的遗传发现，派姆单抗治疗分两个周期进行.不幸的是,治疗无效,患者在手术后5个月出院后死亡。
结论：在这种对ICI反应较差的MSI-HCRC病例中的发现表明确认HLA状态的重要性，包括β-2-微球蛋白和HLA表达，在MSI-HCRC病例开始ICI治疗之前。
方法：一名80岁的女性到我院就诊，主诉降结肠癌引起的肠梗阻引起下腹痛。金属支架滞留1个月后,她接受了根治性手术,虽然剖腹手术显示广泛的腹膜播散。基于MSI-H状态的遗传发现，派姆单抗治疗分两个周期进行.不幸的是,治疗无效,患者在手术后5个月出院后死亡。
结论：在这种对ICI反应较差的MSI-HCRC病例中的发现表明确认HLA状态的重要性，包括β-2-微球蛋白和HLA表达，在MSI-HCRC病例开始ICI治疗之前。
