Development and External Validation of Web-Based Models to Predict the Prognosis of Remnant Gastric Cancer after Surgery: A Multicenter Study

The safety, feasibility, and oncological outcomes of laparoscopic completion total gastrectomy for remnant gastric cancer: a prospective study with 3-year follow-up (FUGES-004 study)

BACKGROUND

The efficacy of laparoscopic completion total gastrectomy (LCTG) for remnant gastric cancer (RGC) remains controversial.

METHODS

The primary outcome was postoperative morbidity within 30 days after surgery. Secondary outcomes included 3-year disease-free survival (DFS), 3-year overall survival (OS), and recurrence. Inverse probability treatment weighted (IPTW) was used to balance the baseline between LCTG and OCTG.

RESULTS

Final analysis included 46 patients with RGC who underwent LCTG at the FJMUUH between June 2016 and June 2020. The historical control group comprised of 160 patients who underwent open completion total gastrectomy (OCTG) in the six tertiary teaching hospitals from CRGC-01 study. After IPTW, no significant difference was observed between the LCTG and OCTG groups in terms of incidence (LCTG vs. OCTG: 28.0 vs. 35.0%, P =0.379) or severity of complications within 30 days after surgery. Compared with OCTG, LCTG resulted in better short-term outcomes and faster postoperative recovery. However, the textbook outcome rate was comparable between the two groups (45.9 vs. 32.8%, P =0.107). Additionally, the 3-year DFS and 3-year OS of LCTG were comparable to those of OCTG (DFS: log-rank P =0.173; OS: log-rank P =0.319). No significant differences in recurrence type, mean recurrence time, or 3-year cumulative hazard of recurrence were observed between the two groups (all P >0.05). Subgroup analyses and concurrent comparisons demonstrated similar trends.

CONCLUSIONS

This prospective study suggested that LCTG was noninferior to OCTG in both short-term and long-term outcomes. In experienced centers, LCTG may be considered as a viable treatment option for RGC.

Visualising statistical models using dynamic nomograms

Translational Statistics proposes to promote the use of Statistics within research and improve the communication of statistical findings in an accurate and accessible manner to diverse audiences. When statistical models become more complex, it becomes harder to evaluate the role of explanatory variables on the response. For example, the interpretation and communication of the effect of predictors in regression models where interactions or smoothing splines are included can be challenging. Informative graphical representations of statistical models play a critical translational role; static nomograms are one such useful tool to visualise statistical models. In this paper, we propose the use of dynamic nomogram as a translational tool which can accommodate models of increased complexity. In theory, all models appearing in the literature could be accompanied by the corresponding dynamic nomogram to translate models in an informative manner. The R package presented will facilitate this communication for a variety of linear and non-linear models.

Current controversies in treating remnant gastric cancer: Are minimally invasive approaches feasible?

The incidence of remnant gastric cancer (RGC) is still increasing. Minimally invasive approaches including endoscopic resection, laparoscopic and robotic approaches, and function-preserving gastrectomy have been utilized as curative treatment methods for primary gastric cancer. However, adhesions and anatomical alterations due to previous gastrectomy make the use of minimally invasive approaches complicated and difficult for RGC. Application of these approaches for the treatment of RGC is still controversial. Endoscopic submucosal dissection is a favorable alternative therapy for the resection of early gastric cancer that occurs in the remnant stomach and can prevent unnecessary complications. The majority of retrospective studies have shown that endoscopic submucosal dissection is an effective and oncologically safe treatment modality for RGC. Subtotal gastrectomy could serve as a function-preserving gastrectomy for patients with early RGC and improve postoperative late-phase function. However, there are only two studies that demonstrate the feasibility and oncological efficacy of subtotal gastrectomy for RGC. The non-randomized controlled trials showed that compared to open gastrectomy, laparoscopic gastrectomy for RGC led to better short-term outcomes and similar oncologic results. Because of the rarity of RGC, future multicenter studies are required to determine the indications of minimally invasive treatment for RGC.