Feasibility of laparoscopic/robot-assisted surgery for Borrmann type 4 gastric cancer: a comparison study with conventional open surgery.

BACKGROUND: Laparoscopic surgery for early gastric cancer is regarded as a standard of care because of robust evidences obtained by several phase-III trials. Furthermore, the efficacy of laparoscopic radical surgery for advanced gastric cancer has been also reported. Meanwhile, the feasibility of laparoscopic surgery for Bormann type 4 gastric cancer, special type with unfavorable prognosis, remains unclear since excluded from eligibility of these trials. METHODS: This study included 100 patients with type 4 gastric cancer who underwent laparoscopic/robot-assisted (minimally invasive surgery (MIS) group; n = 32) or open (Open group; n = 68) curative surgery between 2008 and 2021. After propensity score matching, 30 patients in each group were extracted for analysis. Clinical data, including surgical and midterm survival outcomes, were retrospectively compared between the two groups. RESULTS: Incidences of postoperative complication (≥ Clavien-Dindo grade III) were recorded in 23.3% in the MIS group and 13.3% in the Open group, but no statistical significance was demonstrated (P = 0.50). The 3-year overall survival rate in the MIS group was better than that in the Open group (80.2% vs. 53.5%, log-rank, P = 0.03). The trend of recurrence site was similar. Multivariate analysis showed that adjuvant chemotherapy was an independent favorable prognostic factor (hazard ratio, 0.33, 95% confidence interval 0.11-0.93) for overall survival. MIS was indicated as a favorable prognostic factor (hazard ratio, 0.39, 95% confidence interval 0.39-1.07), but without statistical difference. CONCLUSION: While multidisciplinary treatment is mainstay of treatment because of the poor prognosis of this disease, minimally invasive surgery may play an important role in treatment if appropriate patient selection is done. Further analyses with larger sample size are necessary to reach a final conclusion regarding oncological efficacy.

Impact of postoperative intra-abdominal infectious complications on survival outcomes in patients with gastric cancer who underwent laparoscopic surgery.

BACKGROUND: Postoperative intra-abdominal infection is known to adversely affect survival outcomes in patients with gastric cancer; however, previous reports have investigated this complication only in open surgery. This adverse effect is expected to be weakened by less invasive surgery, such as a laparoscopic approach, by way of maintaining immune function. METHODS: This study included 1223 patients with gastric cancer who underwent open (n = 439) or laparoscopic (n = 784) curative surgery between 2010 and 2015. For each approach, patients were divided into two groups based on presence or absence of postoperative intra-abdominal infection of Clavien-Dindo grade II or higher (C-group and NC-group, respectively). Survival outcomes were compared in propensity-matched cohorts to evaluate the impact of the complication. RESULTS: The incidences of Clavien-Dindo ≥ grade II postoperative intra-abdominal infectious complications were 9.7% (43/439) in open surgery and 9.8% (70/714) in laparoscopic surgery. After propensity score matching, 86 patients in open surgery and 138 in laparoscopic surgery were extracted for analysis. The 5-year overall survival rate in the open C-group (n = 43) was worse than that in the open NC-group (n = 43) but with no significant difference (70.9% vs. 82.8%, log-rank P = 0.18). The 5-year overall survival rates were equivalent between the laparoscopic C-group (n = 69) and the laparoscopic NC-group (n = 69) (90.5% vs. 90.4%, log-rank P = 0.99). CONCLUSION: In general, postoperative intra-abdominal infection adversely affects survival outcomes; however, its impact may be weakened by less invasive surgery. Further evaluation using larger datasets is necessary before reaching definitive conclusions.

Advantages of robotic gastrectomy for overweight patients with gastric cancer: a comparison study of robotic gastrectomy and conventional laparoscopic gastrectomy.

PURPOSE: A high body mass index (BMI) generally increases the risk of postoperative complications because of the intraperitoneal adipose tissue. Robotic gastrectomy (RG) decreases the surgical difficulty of conventional laparoscopic gastrectomy (LG) for these patients. We conducted the present study to identify the advantages of RG over LG for overweight patients. METHODS: We reviewed clinical data on patients who underwent either LG or RG at the National Cancer Center Hospital East between January, 2014 and May, 2022. RESULTS: The 1298 patients eligible patients were divided into a non-overweight cohort (n = 996) (LG, n = 818; RG, n = 178) and an overweight cohort (n = 302) (LG, n = 250; RG, n = 52) according to a BMI cut-off of 25 kg/m2. In the overweight cohort, the RG group had a lower incidence of grade ≥ III postoperative complications (0.0 vs. 8.8%, p = 0.01) and grade ≥ II postoperative complications (11.5 vs. 22.0%, p = 0.12) than the LG group. Multivariate analysis identified that RG was significantly associated with a lower incidence of grade ≥ II postoperative complications in the overweight cohort (odds ratio, 0.33; 95% confidence interval, 0.12-0.87; p = 0.02). CONCLUSIONS: RG may reduce the risk of postoperative complications, compared with conventional LG, in overweight patients.

Complete response to definitive chemoradiotherapy in unresectable locally advanced esophageal squamous cell carcinoma.

BACKGROUND: Although definitive chemoradiotherapy (CRT) is the standard therapy for patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC), poor survival has been reported. Although the complete response (CR) rate is strongly correlated with good prognosis, the predictive factors for CR have not been elucidated. METHODS: This registry study aimed to identify predictors of CR to definitive CRT in patients with unresectable locally advanced ESCC. "Unresectable" was defined as the primary lesion invading unresectable adjacent structures such as the aorta, vertebral body, and trachea (T4b), or the regional and/or supraclavicular lymph nodes invading unresectable adjacent structures (LNT4b). RESULTS: Overall, 175 patients who started definitive CRT between January 2013 and March 2020 were included. The confirmed CR (cCR) rate was 24% (42/175). The 2-year progression-free survival (PFS) and overall survival (OS) rates of cCR cases vs. non-cCR cases were 59% vs. 2% (log-rank p < 0.001) and 90% vs. 31% (log-rank p < 0.001), with a median follow-up period of 18.5 and 40.5 months, respectively. Multivariate analysis of clinicopathological factors revealed that tumor length ≥ 6 cm [odds ratio (OR) 0.446; 95% CI 0.220-0.905; p = 0.025] was a predictor of cCR. CONCLUSIONS: Favorable PFS and OS rates were observed in patients with cCR. Tumor length was a predictive factor for cCR.

Reduction in postoperative complications by robotic surgery: a case-control study of robotic versus conventional laparoscopic surgery for gastric cancer.

BACKGROUND: Robotic gastrectomy (RG) is being increasingly performed globally; it is considered an evolved type of conventional laparoscopic surgery with excellent dexterity and precision, but higher costs and longer operation time. Thus, there is a need to identify the benefits from RG and its specific candidates. METHODS: This retrospective study analyzed data from a prospectively collected clinical database at our center. Data of patients with primary gastric cancer undergoing either robotic or laparoscopic radical gastrectomy from June 2014 to June 2020 were reviewed. Surgical outcomes were compared between the two groups, and multivariable analyses were performed to elucidate the relevant factors for postoperative complications in several subgroups. RESULTS: A total of 1172 patients were divided into those who underwent RG (n = 152) and those who underwent laparoscopic gastrectomy (LG) (n = 1020). Baseline characteristics were similar in the two groups, except the RG group included more patients undergoing total/proximal gastrectomy (TG/PG) and patients at clinical stage III. Compared with the LG group, the RG group had lower incidences of postoperative complications ≥ Clavien-Dindo grade III (2/152 (1.3%) versus 72/1020 (7.1%); P = 0.004), and intraabdominal complications ≥ grade II (6/152 (3.9%) versus 119/1020 (11.7%); P = 0.004). Multivariable analysis revealed that RG was a significant relevant factor for reducing overall postoperative complications (≥ grade III) (odds ratio (OR) 0.16, P = 0.013), and intraabdominal complications (≥ grade II) (OR 0.29, P = 0.002). Subgroup analyses demonstrated that this tendency was enhanced in patients undergoing TG/PG (OR 0.29, P = 0.021) or at clinical stage II/III (OR 0.10, P = 0.027). CONCLUSIONS: RG reduces the incidence of postoperative complications compared with conventional LG and this tendency may be enhanced in technically complicated procedures with demanding anastomosis or D2 lymphadenectomy. Patients requiring such procedures would most benefit from RG.

Definitive chemoradiotherapy induces T-cell-inflamed tumor microenvironment in unresectable locally advanced esophageal squamous cell carcinoma.

BACKGROUND: Chemoradiotherapy (CRT) modulates the tumor immune microenvironment of multiple cancer types, including esophageal cancer, which potentially induces both immunogenicity and immunosuppression by upregulating the presentation of tumor-specific antigens and immune checkpoint molecules in tumors, respectively. The prognostic effects of immune modification by CRT in esophageal squamous cell carcinoma (ESCC) remain controversial because of the lack of detailed immunological analyses using paired clinical specimens before and after CRT. We aimed to clarify the immunological changes in the tumor microenvironment caused by CRT and elucidate the predictive importance of clinical response and prognosis and the rationale for the necessity of subsequent programmed cell death protein 1 (PD-1) inhibitor treatment. METHODS: In this study, we performed a comprehensive immunological analysis of paired biopsy specimens using multiplex immunohistochemistry before and after CRT in patients with unresectable locally advanced ESCC. RESULTS: CRT significantly increased the intra-tumoral infiltration and PD-1 expression of CD8+ T cells and conventional CD4+ T cells but decreased those of regulatory T cells and the accumulation of tumor-associated macrophages. Multivariate analysis of tumor-infiltrating T-cell phenotypes revealed that the density of PD-1+CD8+ T cells in the tumor after CRT could predict a confirmed complete response and favorable survival. CONCLUSIONS: This study showed that CRT improved the immunological characteristics of unresectable locally advanced ESCC and identified the density of PD-1+CD8+ T cells as a predictive factor for prognosis. This finding supports the rationale for the necessity of subsequent PD-1 inhibitor treatment.

The Significance of Staging Laparoscopy in Detection of Radiologically Occult Peritoneal Carcinomatosis in Gastric Cancer With Gastric Outlet Obstruction: Consideration of The Optimal Treatment Approach.

BACKGROUND/AIM: Gastric cancer with gastric outlet obstruction (GOO) is generally found at an advanced stage and with an unfavorable prognosis. This study was performed to examine the prevalence of radiologically occult peritoneal carcinomatosis in GOO and determine the optimal treatment strategy. PATIENTS AND METHODS: This single-center study was a retrospective review of the clinical data of 186 patients with locally advanced gastric cancer at the distal stomach who underwent surgery from 2008 to 2016. These patients were divided into two groups according to the presence or absence of GOO due to cancer progression: With GOO (n=71) and without GOO (n=115). RESULTS: The incidence of peritoneal carcinomatosis [with macroscopic peritoneal deposits (P1)/positive peritoneal cytology (CY1)] detected at laparotomy/laparoscopy was significantly higher in the group with GOO than in the group without (32.4% vs. 9.6%, p<0.01). The R0 resection rate was lower in the group with GOO (62.0% vs. 87.0%, p<0.01). The 5-year overall survival rate was also lower in the group with GOO (43.9% vs. 68.5%, p<0.01). However, in the subset of patients who underwent R0 surgery, the 5-year rates were similar for the two groups (67.4% vs. 73.1%, p=0.91). The multivariable analysis showed that a type 3 tumor appearance (odds ratio=3.66) and presence of GOO (odds ratio=2.87) were predictors of peritoneal carcinomatosis. CONCLUSION: The prevalence of radiologically occult peritoneal carcinomatosis in gastric cancer with GOO exceeded 30%. Staging laparoscopy (gastrojejunal bypass, if needed) should be performed to determine the optimal treatment plan.

Laparoscopic treatment of a vesicointestinal fistula due to a Meckel's diverticulum: a case report and review of the literature.

While there have been numerous reports about colovesical fistulas and ruptured intestinal diverticula, there have been far fewer reports about vesicointestinal fistulas caused by Meckel's diverticula. Most Meckel's diverticula are asymptomatic. Furthermore, they seldom cause vesicointestinal fistulas, and the associated complications are non-specific. Thus, their preoperative diagnosis is difficult. We experienced a case in which a vesicointestinal fistula was caused by a Meckel's diverticulum and was treated with laparoscopic surgery. A 46-year-old male was referred to our hospital after exhibiting hematuria. Cystoscopy revealed a fistula between the small intestine and bladder. Contrast-enhanced computed tomography and magnetic resonance imaging showed a diverticulum in the ileum and a fistula between the ileum and bladder, which passed through the diverticulum. A Meckel's diverticulum was suspected. We conducted a laparoscopic operation. We dissected the Meckel's diverticulum with an automatic suturing device and removed it together with part of the ileum. The patient's postoperative course was good. We experienced a case in which a vesicointestinal fistula was caused by a Meckel's diverticulum and was successfully treated with laparoscopic surgery. In selected cases of Meckel's diverticulum, the dissection of the diverticulum with an automatic suturing device is appropriate.