Australian gastroenterologists have advised caution with endoscopic full-thickness resection (EFTR) of malignant colorectal lesions, despite reports of high technical efficacy and safety.
In an editorial in Gastrointestinal Endoscopy, Dr Neal Shahidi and Professor Michael Bourke from Westmead Hospital’s department of gastroenterology and hepatology warned that “new is not necessarily better” and that “clinical over-reach remains a constant threat” in endoscopic tissue resection.
The clinicians were responding to a retrospective German study of 156 patients who underwent EFTR after incomplete resection of malignant polyps or non-lifting lesions.
The study reported technical success – reaching the lesion, successful clip application and macroscopically complete resection of the lesion – in 92.3% of cases.
R0 resection – complete histologic resection including tumour-free lateral and deep margins – was achieved in 71.8% of cases.
The study investigators reported that definitive discrimination between high-risk and low-risk lesions was possible in all but one case (99.4%). Just over half the high-risk lesions (54%) were resected completely with 34% going onto oncological resection.
The adverse event rate was 14% with severe adverse events such as surgery for perforations in 3.9% of cases.
“Our data indicate that EFTR for colorectal cancer is feasible and safe,” they concluded.
“In our study, 84.1% of patients were finally classified as low risk and were identified correctly not to be candidates for oncologic surgical resection. In other words, EFTR obviated the need for surgery in the majority of these patients and may therefore be the method of choice for this indication [incidentally found malignant polyps].”
In the non-lifting lesions, a majority of lesions (83%) was finally classified as high risk and surgical resection was recommended.
However a primary EFTR approach was justified, they said.
“As a primarily diagnostic procedure for tissue acquisition, it allows exact histologic risk stratification in order to assign patients individually to the best treatment and avoid surgery for low-risk lesions.”
“For patients with high-risk lesions unfit for surgery, it might also be a valuable option for local endoscopic treatment.”
In their commentary, the Australian gastroenterologists said that although EFTR was promising, there were concerns about its curative potential for submucosal invasive cancer (SMIC) and long-term follow-up data was still required. Surgery remained the primary treatment strategy for fit patients with deep SMIC, they emphasised.
“For this indication, EFTR should be considered only within the confines of a clearly defined research protocol,” they advised.
“EFTR is an exciting new addition to the field of advanced colorectal tissue resection. However, the novelty must not outweigh the logical clinical benefit or replace registered clinical trials. Registry-based studies are not sufficient to answer important safety and efficacy questions, nor can they appropriately define the role of any new technology within the existing suite of established therapies.”
A potential application of EFTR may be for patients with lesions at high risk for deep SMIC who are not surgical candidates, they added.