Artificial intelligence for surgical safety during laparoscopic gastrectomy for gastric cancer: Indication of anatomical landmarks related to postoperative pancreatic fistula using deep learning.

BACKGROUND: Postoperative pancreatic fistula (POPF) is a critical complication of laparoscopic gastrectomy (LG). However, there are no widely recognized anatomical landmarks to prevent POPF during LG. This study aimed to identify anatomical landmarks related to POPF occurrence during LG for gastric cancer and to develop an artificial intelligence (AI) navigation system for indicating these landmarks. METHODS: Dimpling lines (DLs)-depressions formed between the pancreas and surrounding organs-were defined as anatomical landmarks related to POPF. The DLs for the mesogastrium, intestine, and transverse mesocolon were named DMP, DIP, and DTP, respectively. We included 50 LG cases to develop the AI system (45/50 were used for training and 5/50 for adjusting the hyperparameters of the employed system). Regarding the validation of the AI system, DLs were assessed by an external evaluation committee using a Likert scale, and the pancreas was assessed using the Dice coefficient, with 10 prospectively registered cases. RESULTS: Six expert surgeons confirmed the efficacy of DLs as anatomical landmarks related to POPF in LG. An AI system was developed using a semantic segmentation model that indicated DLs in real-time when this system was synchronized during surgery. Additionally, the distribution of scores for DMP was significantly higher than that of the other DLs (p < 0.001), indicating the relatively high accuracy of this landmark. In addition, the Dice coefficient of the pancreas was 0.70. CONCLUSIONS: The DLs may be used as anatomical landmarks related to POPF occurrence. The developed AI navigation system can help visualize the DLs in real-time during LG.

Clinical importance of carcinoembryonic antigen messenger RNA level in peritoneal lavage fluids measured by transcription-reverse transcription concerted reaction for advanced gastric cancer in laparoscopic surgery.

BACKGROUND: Transcription-reverse transcription concerted reaction (TRC) is recognized as a useful method for detecting free cancer cells in the peritoneal cavity and predicting peritoneal recurrence in patients with gastric cancer. Nonetheless, the clinical significance of TRC in laparoscopic surgery remains unclear. This study aimed to evaluate the clinical importance of carcinoembryonic antigen (CEA) messenger RNA (mRNA) level in peritoneal lavage fluids measured by TRC in laparoscopic surgery for locally advanced gastric cancer. METHODS: We enrolled patients with locally advanced gastric cancer who underwent laparoscopic gastrectomy. Peritoneal lavage fluids were collected prior to gastrectomy, and the TRC method was employed to quantify CEA mRNA in peritoneal washes. Overall survival (OS), recurrence-free survival (RFS), and peritoneal recurrence-free survival (PRFS) were analyzed using the Kaplan-Meier method and compared using the log-rank test. Adjusted Cox proportional hazards regression models were used to calculate the hazard ratios (HRs) for CEA mRNA positivity. RESULTS: A total of 100 patients were analyzed in this study. Overall, 22 patients (22%) exhibited CEA mRNA positivity in peritoneal lavage fluids, as measured by TRC. No significant association between CEA mRNA levels and clinicopathological characteristics was observed. Patients who were CEA mRNA-positive in peritoneal lavage fluids had significantly worse OS, RFS, and PRFS than those who were CEA mRNA-negative (p = 0.0059, p < 0.0001, and p = 0.0022, respectively). In the univariate Cox model, the HR for all-cause mortality in CEA mRNA-positive versus CEA mRNA-negative patients was 3.60 (95% CI, 1.33-9.55; p = 0.0129). Multivariate analysis revealed that CEA mRNA positivity was a significant independent factor for recurrence. CONCLUSIONS: TRC enables the detection of free cancer cells in the peritoneal cavity and CEA mRNA levels can help predict the prognosis, even in laparoscopic gastrectomy.

[A recurrence after surgery for colon cancer with metastases of the liver and periaortic lymph nodes, with CR achieved by using bevacizumab+mFOLFOX6].

We have experienced and report here a case of postoperative recurrence of colon cancer with metastases in the liver and the periaortic lymph nodes, where we attained CR through combination therapy with bevacizumab+mFOLFOX6. The patient was a male aged 65. He had already had cecal cancer, metastasis in the para-aortic lymph nodes, and multiple hepatic metastases. The surgery involved right colon resection+partial hepatectomy as well as dissection of the para-aortic and the superior mesenteric lymph nodes. The postoperative stage was SSN3H1P0M1 (#216)-pStage IV. S-1+CPT-11 was chosen as an adjuvant therapy. The para-aortic lymph nodes at the level of renal hilus were found enlarged after 17 courses of the therapy. Hence bevacizumab+mFOLFOX6 was chosen for the first-line treatment. After 14 courses of the therapy, CR was proved on the RECIST standard. On continued chemotherapy, CR has been maintained at present, 2 years and 11 months after the surgery or 10 months after confirmation of CR.

Significantly enhanced CO oxidation activity induced by a change in the CO adsorption site on Pd nanoparticles covered with metal-organic frameworks.

We report the significantly enhanced CO oxidation activity of Pd nanoparticles covered with [Zr6O4(OH)4(BDC)6] (UiO-66, BDC = 1,4-benzenedicarboxylate). The catalytic activity was much higher than those of Pd and Ru nanoparticles on ZrO2. The origin of the enhancement was suggested to be a change in the CO adsorption properties on Pd nanoparticles.