Xue Xiaolei, Li Xiangzhao, Pan Zhihua, Zhao Liang, Ding Yanqing
Department of Pathology, Nanfang Hospital, Southern Medical University Guangzhou, China.
Department of Pathology, School of Basic Medical Sciences, Southern Medical University Guangzhou, China.
Int J Clin Exp Pathol. 2017 Nov 1;10(11):11353-11359. eCollection 2017.
Colon cancer is the third most common cancer diagnosed in both men and women worldwide and one of the leading causes of cancer-related deaths. Based on where the cancer stared, we focused on the left-sided colon cancer and right-sided colon cancer in this study to reveal their pathological characteristics and their relationship to the KRAS gene mutation. From examining a total of 198 colorectal cancer specimens collected during 2013 and 2016 in Nan fang Hospital, we noticed that whether the cancer developed in left side or right side of the colon are highly relevant to the patients gender, age, tumor size, differentiation and distant metastasis. We found that right-sided colon cancers (RCC) are more likely to occur in women, be greater than 5 cm, and occur in patients older than 60 years, while left-sided colon cancers (LCC) are more prevalent in patients with poorly differentiated tumors and tumors with distant metastases. We then randomly selected 113 of the 198 samples and performed Sanger sequencing to examine their gene mutation. The result indicates that KRAS mutation is prominently higher in RCC compare to LCC, especially the mutation on the 12 codon GGT>GAT (G12D). In addition to the location in which the cancer developed, the mutation was also closely associated with the tumor size, degree of tumor differentiation, and lymph node metastasis. There was a significantly higher incidence of mutation in cases with RCC, poorly differentiated tumors, and non-lymph node metastasis compared to LCC with well- or moderately differentiated tumors with lymph node metastasis. Taken together, we determined that there are distinct differences in the clinicopathological characteristics of right-versus left-sided colon cancers and their correlation with the mutation. These differences suggest that practitioners need to diagnose and treat RCC and LCC differently.
结肠癌是全球男性和女性中第三大最常被诊断出的癌症，也是癌症相关死亡的主要原因之一。基于癌症起始的部位，我们在本研究中聚焦于左侧结肠癌和右侧结肠癌，以揭示它们的病理特征以及与KRAS基因突变的关系。通过检查2013年至2016年期间在南方医院收集的总共198份结直肠癌标本，我们注意到癌症在结肠左侧还是右侧发生与患者的性别、年龄、肿瘤大小、分化程度和远处转移高度相关。我们发现，右侧结肠癌（RCC）更易发生于女性，肿瘤大于5厘米，且发生于60岁以上患者，而左侧结肠癌（LCC）在低分化肿瘤和有远处转移的肿瘤患者中更为普遍。然后我们从198个样本中随机选取113个并进行桑格测序以检测它们的基因突变。结果表明，与LCC相比，RCC中的KRAS突变显著更高，尤其是12密码子GGT>GAT（G12D）的突变。除了癌症发生的部位外，该突变还与肿瘤大小、肿瘤分化程度和淋巴结转移密切相关。与伴有淋巴结转移的高分化或中分化LCC相比，RCC、低分化肿瘤和无淋巴结转移的病例中突变发生率显著更高。综上所述，我们确定右侧与左侧结肠癌的临床病理特征及其与突变的相关性存在明显差异。这些差异表明从业者需要对RCC和LCC进行不同的诊断和治疗。
