Laparoscopy, Surgery in a Draw for Gastric Cancer Survival

Relapse-free survival (RFS) data at 5 years showed that laparoscopy-assisted distal gastrectomy (LADG) was noninferior to open distal gastrectomy (ODG) in locally advanced gastric cancer, according to a phase II/III randomized trial from Japan.

Among 500 randomized patients, the 5-year RFS rate was 75.7% in the LADG group and 73.9% in the ODG group, with a hazard ratio of 0.96 (90% CI 0.72-1.26, noninferiority 1-sided P=0.03), reported Tsuyoshi Etoh, MD, PhD, of Oita University in Yufu, Japan, and colleagues.

There was also no significant difference in overall survival (OS) between the two groups (81.7% vs 79.8%, respectively, HR 0.83, 95% CI 0.57-1.21, P=0.34), they noted in JAMA Surgery.

"LADG with D2 lymph node dissection for locally advanced gastric cancer, when performed by qualified surgeons, was proved noninferior to ODG," they wrote. "This laparoscopic approach could become a standard treatment for locally advanced gastric cancer."

Since laparoscopic gastrectomy for locally advanced gastric cancer "is technically demanding," a strength of the study was the fact that participating surgeons were required to have Endoscopic Surgical Skill Qualification System (ESSQS) certification (established by the Japan Society for Endoscopic Surgery to enable surgeons to maintain their laparoscopic technical skills), and to have performed a specified number of both laparoscopic gastrectomy and open gastrectomy procedures. Thus, Etoh and colleagues were able to "ensure high-quality surgical interventions in this trial."

However, in a commentary accompanying the study, Daniel B. Hoffman, MD, and Eric K. Nakakura, MD, PhD, both of the University of California San Francisco Helen Diller Family Comprehensive Cancer Center, noted that since the surgeons participating in the trial were required to have ESSQS certification with additional training, "this may not reflect the reality of gastric cancer care in Western countries, where lower gastric cancer incidence and a lack of centralization of gastrectomies to high-volume centers limit individual surgeon experience."

They also pointed out several other features of the study that should be considered before applying the results to Western populations.

For example, they noted that the median body mass index (BMI) among the study population was 22.5, and the exclusion of patients with a BMI ≥30 means the study population as a whole was less overweight than those seen in Western studies. They also pointed out that neoadjuvant chemotherapy is usually provided to patients with locally advanced gastric adenocarcinomas in Western countries, whereas in this study, patients were exclusively given adjuvant chemotherapy.

The Japanese Laparoscopic Surgery Study Group conducted this open-label, multicenter, prospective study from November 2009 through July 2016. Eligible patients had histologically proven gastric adenocarcinoma, a BMI less than 30, an Eastern Cooperative Oncology Group performance status of 0 or 1 (considered potentially curable by distal gastrectomy), and a clinical diagnosis of muscularis propria, subserosa, and serosal exposure, N0-2 without bulky node metastasis, or M0 lesions without involvement of other organs.

Of the 502 patients included in the full-analysis set, 254 were in the ODG group and 248 were in the LADG group. Patients in the ODG group had a median age of 67, and 66.1% were men. Patients in the LADG group had a median age of 64, and 68.1% were men. The median follow-up for all patients after randomization was 67.9 months.

In both groups, distal gastrectomy with D2 lymph node dissection was performed, according to Japanese treatment guidelines. Staging laparoscopy in the ODG group was recommended for patients at high risk of peritoneal dissemination, and adjuvant chemotherapy was administered 1 year postoperatively when pathological stages II and III (with some exceptions) were confirmed after surgery.

In the full-analysis set, 27.7% in the LADG group and 28.3% in the ODG had recurrence, death, or curability C (definite residual disease). When curability C was excluded from the events, the 5-year RFS rate was 79.9% in the LADG group and 77.6% in the ODG group.

No significant differences were seen in the incidence of intraoperative complications. Any postoperative complications were observed in 11.5% of the LADG group and 10.7% of the ODG group, while those of grade 3 and higher were observed in 3.5% and 4.7%, respectively (P=0.64).

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