Department of Gastroenterology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
Department of General Surgery, Jiangjin Central Hospital of Chongqing, Chongqing 402200, China.
Can J Gastroenterol Hepatol. 2022 Apr 28;2022:2033876. doi: 10.1155/2022/2033876. eCollection 2022.
The lung is the most common extra-abdominal metastasis site of colorectal cancer (CRC). This study aimed to investigate the genetic variation of pulmonary metastases (PM) and primary tumors in resectable CRC. The clinical data of 410 patients with PM after CRC surgery and 33 paraffin-embedded tissue samples from January 2012 to July 2019 in our hospital were collected retrospectively. Next, 450-panel gene detection technologies based on next-generation sequencing (NGS) were used to analyze the changes in the gene map and the overall variation in cancer-related genes in PM and primary tumors. After quality control, 19 samples were included in the final gene analysis. The results showed that APC (89.5%), TP53 (89.5%), and KRAS (53%) were the most common mutations in PM and primary tumors, but the gene amplification variation was enriched in primary tumors (4.6% vs. 11.4%). KRAS G12D was the most common site variation of the KRAS gene in both PM and primary tumors of CRC. There was no hotspot mutation in the TP53 locus in CRC, and the TP53 mutation in the PM was consistent with that in the primary lesion. The microsatellite instability (MSI) levels of 10 patients were MSS. The mean tumor mutation burden (TMB) of the primary tumor (5.3 muts·Mb) was slightly higher than that of metastasis (5.0 muts·Mb). In our institution, the genetic characteristics of resectable PM from CRC may be highly consistent with those of the primary tumor.
肺是结直肠癌（CRC）最常见的腹腔外转移部位。本研究旨在探讨可切除 CRC 患者肺转移瘤（PM）和原发瘤的遗传变异。回顾性收集了我院 2012 年 1 月至 2019 年 7 月 410 例 CRC 术后 PM 患者和 33 例石蜡包埋组织样本的临床资料。然后，采用基于下一代测序（NGS）的 450 面板基因检测技术，分析 PM 和原发瘤中基因图谱的变化和与癌症相关基因的整体变化。经过质量控制，最终有 19 个样本纳入基因分析。结果表明，APC（89.5%）、TP53（89.5%）和 KRAS（53%）是 PM 和原发瘤中最常见的突变，但基因扩增变异在原发瘤中更为丰富（4.6%比 11.4%）。KRAS G12D 是 CRC 中 PM 和原发瘤 KRAS 基因最常见的位点变异。CRC 中 TP53 基因的热点突变缺失，PM 中的 TP53 突变与原发病灶一致。10 例患者的微卫星不稳定性（MSI）水平为 MSS。原发瘤的平均肿瘤突变负荷（TMB）（5.3 muts·Mb）略高于转移瘤（5.0 muts·Mb）。在本研究机构中，可切除 CRC 的 PM 遗传特征可能与原发瘤高度一致。
