Laparoscopic just as effective as open distal gastrectomy for locally advanced gastric cancer
Laparoscopic and open distal gastrectomy provide comparable disease-free survival in patients with locally advanced gastric cancer, according to a recent study.
“This multicentre randomized clinical trial conducted at 14 centres in China among patients with locally advanced gastric cancer … found that the 3-year disease-free survival of patients assigned to the laparoscopic distal gastrectomy group was not inferior to that of patients assigned to the open distal gastrectomy group,” said researchers.
Patients who underwent laparoscopic distal gastrectomy had a 3-year disease-free survival of 76.5 percent. This was marginally lower than that in the open gastrectomy group (77.8 percent), such that the resulting absolute difference was –1.3 percent. The corresponding one-sided 97.5 percent CI ran from –6.5 percent to ∞ and did not cross the prespecified noninferiority threshold of –10 percent. [JAMA 2019;321:1983-1992]
However, exclusion of 303 patients with pathologic stage I malignancies led to an absolute difference of –3.9 percent, whose one-sided 97.5 percent CI (–10.6 percent to ∞) breached the noninferiority margin.
On the other hand, mixed-effects Cox regression analysis, adjusted for age, tumour size, T and N stages, and adjuvant chemotherapy received, confirmed the noninferiority of laparoscopic vs open distal gastrectomy (hazard ratio [HR], 1.10, 95 percent CI, 0.84–1.43; p=0.49).
“Although the current study supports the noninferiority of laparoscopic distal gastrectomy compared with open distal gastrectomy for locally advanced gastric cancer … generalizability of these study results to patients who undergo more intensive initial staging and/or have lower rates of pathologic downstaging is uncertain,” said researchers, pointing out that a large proportion of the trial cohort was overstaged.
In turn, researchers reported that 160 participants died over the 3-year study period, yielding an overall survival rate of 83.1 percent in the laparoscopy group and 85.2 percent in the open gastrectomy group. Multivariable adjusted models found no significant difference in the likelihood of mortality between the two study arms (HR, 1.19, 0.87–1.64; p=0.28).
A similar pattern was observed for recurrence of malignancy. Over 3 years of follow-up, the cumulative incidence rates in the laparoscopic and open gastrectomy groups were 18.8 percent and 16.5 percent, respectively (subhazard ratio, 1.15, 0.86–1.54; p=0.35).
Several studies have established the relative safety of laparoscopic over open gastrectomy for locally advanced gastric cancer, said researchers. Previous trials have shown lower rates of morbidity, quicker recovery and noninferior survival. The comparative oncological efficacy, however, has yet to be determined. [J Clin Oncol 2016;34:1350-1357; Ann Surg 2019;doi: 10.1097/SLA.0000000000003217]
While, “[f]rom the technical point of view, laparoscopic approaches have the benefits over open surgeries through visual magnification, better exposure, and more delicate manoeuvres of organs, vessels, and nerves,” there are concerns that remain unsettled, researchers said.
For instance, “[c]ompared with open gastrectomy, a laparoscopic approach can compromise the ability to perform an adequate D2 lymphadenectomy and a complete resection,” they pointed out. Moreover, laparoscopic manoeuvres could dislodge cancer cells and facilitate its spread to other tissues.
The present study contributes to the existing literature and establishes the noninferiority of efficacy of laparoscopic gastrectomy, they said. Coupled with its superior safety over open distal gastrectomy, the current findings “suggest that the indication for laparoscopic distal gastrectomy could be extended to include locally advanced gastric cancer.”