Intraoperative fluorescence angiography with indocyanine green to prevent anastomotic leak in rectal cancer surgery (IntAct): an unblinded randomised controlled trial.

Therefore, we aimed to investigate the safety and efficacy of ICG fluorescence angiography in reducing the rate of clinical anastomotic leaks in these patients.

因此，我们的目标是研究ICG荧光血管造影在降低这些患者临床吻合口漏发生率方面的安全性和有效性。

Methods

IntAct was an unblinded randomised controlled trialconducted at 28 specialist rectal cancer centres across eight European countries.

IntAct 是一项在欧洲八个国家的28个专业直肠癌中心进行的非盲随机对照试验。

Adults (≥18 years) with rectal cancer (lower margin of cancer ≤15 cm from the anal verge) medically fit for elective, curative, laparoscopic or robotic high or low anterior resection were eligible.

符合条件的成年人（≥18岁）患有直肠癌（肿瘤下缘距离肛门缘≤15厘米），并且医学上适合进行选择性的、根治性的腹腔镜或机器人辅助的高位或低位前切除术。

Patients not undergoing colorectal or anal anastomosis and those with synchronous colonic tumours or recurrent or locally advanced rectal cancer requiring extended or multi-visceral excision were excluded.

未进行结直肠或肛门吻合术的患者，以及那些有同时性结肠肿瘤或需要扩大或多脏器切除的复发性或局部晚期直肠癌患者被排除在外。

Eligible participants were randomly assigned (1:1) by use of minimisation with a random element to undergo surgery with or without ICG (standard care).

符合条件的参与者通过使用带有随机元素的最小化方法随机分配（1:1），接受手术时使用或不使用ICG（标准护理）。

Resections and anastomoses were done per surgeon preference.

手术切除和吻合均根据外科医生的偏好进行。

In the ICG group, surgeons first marked proximal transection levels via standard white-light laparoscopy and then administered an intravenous bolus of 0·1 mg/kg of ICG for perfusion assessment.

在ICG组中，外科医生首先通过标准白光腹腔镜标记近端截断水平，然后静脉注射0.1 mg/kg的ICG以评估灌注。

A second 0·1 mg/kg ICG assessment was done following anastomosis.

在吻合术之后，进行了第二次0.1 mg/kg的ICG评估。

In the standard care group, only a white-light assessment of bowel perfusion was performed.

在标准护理组中，仅进行了肠灌注的白光评估。

The primary endpoint was the rate of clinical anastomotic leak (grades B or C, per the International Study Group of Rectal Cancer) within 90 postoperative days.

主要终点是术后90天内临床吻合口漏（根据国际直肠癌研究组标准，分为B级或C级）的发生率。

Analyses were done in the intention-to-treatpopulation for complete cases.

分析是在意向治疗人群中对完整病例进行的。

This trial is registered with the ISRCTN registry (ISRCTN13334746) and is now complete.

该试验已在ISRCTN注册（ISRCTN13334746），目前研究已完成。

Results

Between Oct 20, 2017, and Aug 15, 2023, 2534 patients were assessed for eligibility and 766 participants were randomly assigned (383 to the ICG group and 383 to the standard care group). 501 (65%) of 766 participants were male, 726 (95%) were of White ethnicity, and the median age was 64·0 years (IQR 56·0-72·0). 343 patients in the ICG group and 355 in the standard care group were included in the intention-to-treatanalysis.

在2017年10月20日至2023年8月15日期间，共有2534名患者被评估是否符合入选资格，766名参与者被随机分配（ICG组383人，标准护理组383人）。

The rates of anastomotic leak were 11 (3%) of 343 in the ICG group and 20 (6%) in the standard care group for grade A, 11 (3%) and 31 (9%) for grade B, and 25 (7%) and 23 (6%) for grade C.

吻合口漏的发生率在ICG组的343名患者中，A级为11例（3%），标准护理组为20例（6%）；B级为11例（3%）和31例（9%）；C级为25例（7%）和23例（6%）。

Within 90 days, a clinical anastomotic leak occurred in 90 (13%) of 698 participants: 36 (10%) of 343 in the ICG group and 54 (15%) of 355 in the standard care group (adjusted odds ratio 0·667 [95% CI 0·419-1·060]; p=0·087).

在90天内，698名参与者中有90例（13%）发生了临床吻合口漏：ICG组的343名中有36例（10%），标准护理组的355名中有54例（15%）（调整后的优势比为0.667 [95% 置信区间0.419-1.060]；p=0.087）。

There were no serious adverse events related to ICG.

未发现与ICG相关的严重不良事件。

interpretation

Although IntAct did not show a significant benefit for ICG fluorescence angiography, a signal towards a reduction in clinical anastomotic leak rate was observed.

尽管IntAct研究未显示出ICG荧光血管造影的显著益处，但观察到临床吻合口漏率降低的信号。

The benefit of ICG could be in preventing grade A or B leaks, given similar rates of grade C leaks between groups.

ICG 的好处可能在于预防 A 级或 B 级漏，因为两组之间的 C 级漏发生率相似。

Future research is needed to standardise ICG fluorescence assessment and understand its relevance to anastomotic leak.

需要进一步研究以标准化 ICG 荧光评估并理解其与吻合口漏的相关性。

funding

National Institute for Health and Care Research Efficacy and Mechanism Evaluation Programme.

国家健康与护理研究机构效能与机制评估计划