探讨Tis期结直肠癌内镜下非治愈性切除的临床特点及外科手术的应用价值。

通过回顾性收集2013年1月至2021年12月期间在广东省中医院胃肠肿瘤中心行内镜下非治愈性切除后接受补救手术治疗的34例Tis期结直肠癌患者的临床资料，总结患者的内镜治疗情况、补救手术指征、术后病理等，并分析导致补救手术实施的主要原因。

全组34例患者中，男性18例，女性16例，中位年龄58（30~78）岁，病变位于右半结肠6例、左半结肠17例、直肠11例。内镜下观察息肉形态属山田Ⅰ型7例、山田Ⅱ型8例、山田Ⅲ型17例、山田Ⅳ型2例；内镜切除方法包括内镜下黏膜切除术（EMR）20例、内镜黏膜下剥离术（ESD）6例、内镜下黏膜分块切除术（EPMR）以及圈套器套扎切除术各4例。追加外科手术的指征包括可疑黏膜下浸润21例（61.8%）、基底切缘距离肿瘤＜1 mm 21例（61.8%）、基底切缘或侧切缘阳性10例（29.4%）、分块切除8例（23.5%）。息肉病理中判断为肿瘤侵犯黏膜肌层24例（70.6%），无患者出现淋巴脉管侵犯或肿瘤出芽。内镜切除与手术切除间隔中位时间为14 d。术后病理结果：共10例（29.4%）患者出现癌残留，包括黏膜内癌残留8例（23.5%）和T1期腺癌残留2例（5.9%）；中位淋巴结检出数12（3~34）枚，无患者出现区域淋巴结转移。癌残留的危险因素包括切缘阳性和分块切除，非可疑黏膜下浸润患者均未出现T1期腺癌残留。

Tis期CRC内镜下切除后病理诊断的不明确性是导致追加补救手术的主要原因，外科治疗决策中可能高估了Tis期CRC发生黏膜下浸润的风险。对于具有手术指征的Tis期结直肠癌患者，手术治疗的肿瘤学获益并不大，定期内镜复查可能是更加安全的选择。

To investigate the clinicopathological characteristics of patients treated with additional surgery after non-curative endoscopic resection for Tis colorectal cancer and estimate the application value of secondary surgery.

The clinical data of 34 patients with Tis colorectal cancer who underwent additional surgery after non-curative endoscopic resection in Gastrointestinal Cancer Center of Guangdong Hospital of Traditional Chinese Medicine from January 2013 to December 2021 were retrospectively collected to analyze the characteristics of endoscopic treatment, indications of additional surgery, postoperative pathological results, and the main reason leading to additional surgery.

Among the 34 patients included, eighteen were male and 16 were female, with a median age of 58 years (range 30~78 years). The lesions were located in right-sided colon, left-sided colon and rectum in 6, 17, and 11 cases respectively. In accordance with Yamada classification, seven cases were classified as type Ⅰ, eight were type Ⅱ, seventeen were type Ⅲ and 2 were type Ⅳ. Endoscopic mucosal resection(EMR), endoscopic submucosal dissection(ESD) and endoscopic piecemeal mucosal resection(EPMR) were performed in 20, 6 and 4 patients respectively, and 4 patients were treated with snaring resection. The indications of additional surgery included suspicious submucosal invasion in 21 cases (61.8%), safety resection margin ＜1 mm in 21 cases (61.8%), positive vertical or lateral resection margin in 10 cases (29.4%) and piecemeal resection in 8 cases (23.5%). Twenty-four (70.6%) patients were diagnosed as tumor invasion of muscularis mucosa, and lymphovascular invasion or tumor budding was present in no patient. The median time between endoscopic resection and surgery was 14 days. Postoperative pathological results showed that residual tumor was present in 10 patients (29.4%) including intramucosal carcinoma 8 cases (23.5%) and T1 adenocarcinoma in 2 cases (5.9%). The median number of total retrieved lymph nodes was 12 (range 3~34), and there was no patient confirmed lymph node metastasis. The risk factors for residual tumor included positive resection margin and piecemeal resection.

The ambiguous pathological diagnosis after endoscopic resection is the main reason leading to additional surgery for Tis CRC. The risk of submucosal invasion might be overestimated in Tis CRC when making surgical decisions. As a result, the oncological benefit of surgical treatment was limit for Tis CRC patients with surgical indications and endoscopic surveillance might be a safer strategy.