Minimally invasive surgery in gastric cancer

Current Issues in Reduced-Port Gastrectomy: A Comprehensive Review

Reduced-port gastrectomy (RPG) includes all procedures derived from various efforts to minimize surgical invasiveness, with single-incision laparoscopic gastrectomy (SILG) being the ultimate reduced-port technique. However, there are challenges related to its feasibility, oncological validity, training, and education. This review describes the current issues and challenges, as well as the future prospects of RPG for gastric cancer. Gastrectomy, which started as an open surgery, has evolved into a laparoscopic surgery. With the advancements in laparoscopic technology, SILG has been used to minimize surgical scarring. However, owing to the technical difficulties of SILG, cases involving the addition of 1 trocar or needle grasper alongside the multichannel port have also been reported. Additionally, 3-port laparoscopic gastrectomy (3PLG) using only 3 trocars is also being performed. RPG, as a concept, includes a range of approaches such as SILG, 2-port laparoscopic gastrectomy, and 3PLG. These techniques aimed to reduce the number of ports or incisions required for laparoscopic gastrectomy. Despite technical difficulties, RPGs offer numerous advantages, including minimal invasiveness, excellent cosmetic outcomes, and the potential for improved post-operative recovery, such as reduced length of hospital stay and post-operative pain. It could be considered similar to conventional laparoscopic gastrectomy, and may not be oncologically inferior. Ongoing studies, such as the KLASS 12, are required to gain further insights.

Safety and efficacy of robotic-assisted versus laparoscopic distal gastrectomy after neoadjuvant chemotherapy for advanced gastric cancer

BACKGROUND

Robot-assisted distal gastrectomy (RADG) has been used in the minimally invasive surgical treatment of gastric cancer, but the research on advanced gastric cancer (AGC) after neoadjuvant chemotherapy (NAC) has not been reported. This study aimed to analyze the outcomes of RADG versus laparoscopic distal gastrectomy (LDG) after NAC for AGC.

METHODS

This was a retrospective propensity score-matched analysis from February 2020 and March 2022. Patients who underwent RADG or LDG for AGC (cT3-4a/N +) following NAC were enrolled and a propensity score-matched analysis was performed in a 1:1 manner. The patients were divided into RADG group and LDG group. The clinicopathological characteristics and short-term outcomes were observed.

RESULTS

After propensity score matching, 67 patients each in the RADG and LDG groups. RADG was associated with a lower intraoperative blood loss (35.6 vs. 118.8 ml, P = 0.014) and more retrieved lymph nodes (LNs) (50.7 vs. 39.5, P < 0.001), more extraperigastric (18.3 vs. 10.4, P < 0.001), and suprapancreatic LNs (16.33 vs. 13.70, P = 0.042). The RADG group showed lower VAS scores at postoperative 24 h (2.2 vs 3.3, P = 0.034), earlier ambulation (1.3 vs. 2.6, P = 0.011), aerofluxus time (2.2 vs. 3.6, P = 0.025), and shorter postoperative hospital stay (8.3 vs. 9.8, P = 0.004). There were no significant differences in the operative time (216.7 vs.194.7 min, P = 0.204) and postoperative complications between the two groups.

CONCLUSION

RADG may be a potential therapeutic option for patients with AGC after NAC considering its advantages in perioperative period compared with LDG.

Surgical Treatment for Gastric Cancer

Surgery is an essential component of curative-intent treatment strategies for gastric cancer. However, the care of each patient with gastric cancer must be individualized based on patient and tumor characteristics. It is important that all physicians who will be caring for patient with gastric cancer understand the current best practices of surgical management to provide patients with the highest quality of care. This article aims to provide this information while acknowledging areas of surgical management that are still controversial.

Surgical Management of Gastric Cancer: A Systematic Review

Gastric cancer is the fifth most common cancer worldwide, and it is responsible for 7.7% of all cancer deaths. Despite advances in the field of oncology, where radiotherapy, neo and adjuvant chemotherapy may improve the outcome, the only treatment with curative intent is represented by surgery as part of a multimodal therapy. Two concepts may be adopted in appropriate cases, neoadjuvant treatment before gastrectomy (G) or primary surgical resection followed by chemotherapy. Such an approach, combined with early detection and better screening, has led to a decrease in the overall incidence of gastric cancer. Unfortunately, malignant tumors of the stomach are often diagnosed in locally advanced or metastatic stages when the median overall survival remains poor. Surgical care in these cases must be provided by a multidisciplinary team in a high-volume center. Important surgical aspects such as optimum resection margins, surgical technique, and number of harvested lymph nodes are important factors for patient outcomes. The standardization of surgical treatment of gastric cancer in accordance with the patient’s profile is of decisive importance for a better outcome. This review aims to summarize the current standards in the surgical treatment of gastric cancer.

Laparoscopic versus open distal gastrectomy for advanced gastric cancer: A meta-analysis of randomized controlled trials and high-quality nonrandomized comparative studies

BACKGROUND

Controversy persists about the effects of laparoscopic distal gastrectomy (LDG) versus open distal gastrectomy (ODG) on short-term surgical outcomes and long-term survival within the field of advanced gastric cancer (AGC).

METHODS

Studies published from January 1994 to February 2020 that compare LDG and ODG for AGC were identified. All randomized controlled trials (RCTs) were included. The selection of high-quality nonrandomized comparative studies (NRCTs) was based on a validated tool (Methodological Index for Nonrandomized Studies, MINORS). The short- and long-term outcomes of both procedures were compared.

RESULTS

Overall, 30 studies were included in this meta-analysis, which comprised of 8 RCTs and 22 NRCTs involving 16,029 patients (7864 LDGs, 8165 ODGs). The recurrence, 3-year disease-free survival (DFS), 3-year overall survival (OS), and 5-year OS rates for LDG and ODG were comparable. LDG was associated with a lower postoperative complication rate (OR 0.79; P < 0.00001), lower estimated volume of blood loss (WMD -102.21 mL; P < 0.00001), shorter postoperative hospital stay (WMD -1.96 days; P < 0.0001), shorter time to first flatus (WMD -0.54 day; P = 0.0007) and shorter time to first liquid diet (WMD -0.66 day; P = 0.001). The number of lymph nodes retrieved, mortality, intraoperative complications, intraoperative blood transfusion, and time to ambulation were similar. However, LDG was associated with a longer surgical time (WMD 33.57 min; P < 0.00001).

CONCLUSIONS

LDG with D2 lymphadenectomy is a safe and effective technique for patients with AGC when performed by experienced surgeons at high-volume specialized centers.

Effect of Laparoscopic Distal Gastrectomy vs Open Distal Gastrectomy on Long-term Survival Among Patients With Stage I Gastric Cancer: The KLASS-01 Randomized Clinical Trial

Importance

Laparoscopic distal gastrectomy is gaining popularity over open distal gastrectomy for gastric cancer because of better early postoperative outcomes. However, to our knowledge, no studies have proved whether laparoscopic distal gastrectomy is oncologically equivalent to open distal gastrectomy.

Objective

To examine whether the long-term survival among patients with stage I gastric cancer undergoing laparoscopic distal gastrectomy is noninferior to that among patients undergoing open distal gastrectomy.

Design

The Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS) group, which includes 15 surgeons from 13 institutes, conducted a phase 3, multicenter, open-label, noninferiority, prospective randomized clinical trial (KLASS-01) of patients with histologically proven, preoperative clinical stage I gastric adenocarcinoma from January 5, 2006, to August 23, 2010. Survival and recurrence status of the patients was determined in December 2016.

Interventions

Patients were randomly assigned (1:1) to laparoscopic distal gastrectomy (n = 705) or open distal gastrectomy (n = 711). Of these patients, 85 received a surgical approach opposite the one to which they were randomized (63 randomized to the open surgery group and 22 to the laparoscopic group).

Main Outcomes and Measures

Difference in 5-year overall survival between the laparoscopic and open distal gastrectomy groups. The noninferiority margin was prespecified as -5% (corresponding hazard ratio of 1.54), with an assumed survival of 90% after 5 years in the open surgery group.

Results

Among the 1416 patients (mean [SD] age, 57.3 [11.1] years; 940 [66.4%] male) included in the study, the 5-year overall survival rates were 94.2% in the laparoscopic group and 93.3% in the open surgery group (log-rank P = .64). Intention-to-treat analysis confirmed the noninferiority of the laparoscopic approach compared with the open approach (difference, 0.9 percentage points; 1-sided 97.5% CI, -1.6 to infinity). The 5-year cancer-specific survival rates were similar between the 2 groups (97.1% in the laparoscopic group and 97.2% in the open surgery group, log-rank P = .91; difference, -0.03 percentage points; 1-sided 97.5% CI, -1.8 to infinity). Per-protocol analysis results were consistent with the intention-to-treat results for overall and cancer-specific survival rates.

Conclusions and Relevance

The KLASS-01 trial revealed similar overall and cancer-specific survival rates between patients receiving laparoscopic and open distal gastrectomy. Laparoscopic distal gastrectomy is an oncologically safe alternative to open surgery for stage I gastric cancer.

Trial Registration

ClinicalTrials.gov identifier: NCT00452751.

Polymorphisms of the DNA Methyltransferase 1 Gene Predict Survival of Gastric Cancer Patients Receiving Tumorectomy

DNA methyltransferase 1 (DNMT1) plays a pivotal role in maintaining DNA methylation status. Polymorphisms of DNMT1 may modify the role of DNMT1 in prognosis of gastric cancer (GC). Our aim was to test whether polymorphisms of DNMT1 gene were associated with overall survival of GC. Four hundred and forty-seven GC patients who underwent radical tumorectomy were enrolled in the study. Five tagging SNPs (rs10420321, rs16999593, rs2228612, rs2228611, and rs2288349) of the DNMT1 gene were genotyped by TaqMan assays. Kaplan-Meier survival plots and Cox proportional hazard regression were used to analyze the associations between SNPs of DNMT1 and survival of GC. Patients carrying rs2228611 GA/AA genotype tended to live longer than those bearing the GG genotype (HR 0.68, 95% CI: 0.51–0.91, P = 0.007). Further multivariate Cox regression analysis showed that rs2228611 was an independent prognostic factor (GA/AA versus GG: OR 0.67, 95% CI 0.49–0.91, P = 0.010). Nevertheless, other SNPs did not show any significant associations with survival of GC. Polymorphisms of the DNMT1 gene may affect overall survival of GC. The SNP rs2228611 has the potentiality to serve as an independent prognostic marker for GC patients.

Feasibility of hyperthermic pressurized intraperitoneal aerosol chemotherapy in a porcine model

BACKGROUND

Peritoneal carcinomatosis is an unmet therapeutic need. Several types of intraperitoneal chemotherapy have been introduced. However, hyperthermic intraperitoneal chemotherapy has limited drug distribution and poor peritoneal penetration. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) does not have the benefits of hyperthermia. We developed a device to apply hyperthermic PIPAC (H-PAC) and evaluated its feasibility in a porcine model.

METHODS

The device for H-PAC consisted of a laparoscopic aerosol spray and a heater to create hyperthermic capnoperitoneum. We operated on five pigs for the development of the new device and on another five pigs as a survival model. After a pilot experiment of the survival model (Pig A), a hyperthermic pressurized intraperitoneal aerosol of indocyanine green was administered after insertion of three trocars (Pig B) and laparoscopy-assisted distal gastrectomy (LADG) (Pig C) without chemotherapeutic agents. After that, H-PAC with cisplatin was administered after insertion of three trocars (Pig D) and LADG (Pig E). Autopsies were performed on postoperative day 7.

RESULTS

Median operation time was 85 min (80-110 min). Intraperitoneal temperature was constant for 1 h of H-PAC (38.8-40.2 °C). All five pigs were healthy and survived for 7 days. Median weight loss was 0.2 kg. Autopsy tissues of stomach, peritoneum, and jejunum were intact in all five pigs.

CONCLUSIONS

H-PAC was feasible and safe in a porcine model.

Eleven-year experience with 3000 cases of laparoscopic gastric cancer surgery in a single institution: analysis of postoperative morbidities and long-term oncologic outcomes

BACKGROUND

The present study summarizes the 11-year laparoscopic gastric cancer surgery experience of a single institution in South Korea and evaluates the current trends of laparoscopic gastric cancer surgery through our experience.

METHODS

A total of 3000 minimally invasive gastric cancer surgeries were performed at Seoul National University Bundang Hospital between May 2003 and January 2014. The types of laparoscopic gastrectomy used, surgical techniques, postoperative morbidities, and long-term oncologic outcomes were analyzed.

RESULTS

The proportion of challenging procedures such as laparoscopic total gastrectomy and laparoscopic gastrectomy for patients with advanced gastric cancer increased during the study period. The frequency of laparoscopic function-preserving gastrectomy for patients with early-stage cancer also increased. The overall rate of complications was 16.7 %; surgical and systemic complication rates were 11.8 and 6.2 %, respectively. There was one case of postoperative mortality due to delayed bleeding after discharge. Male gender, high BMI, long operating times, combined resection of other organs, and total and proximal gastrectomies were independent predictors of surgical morbidities; however, pathologic T-stage was not a predictable factor. Accumulated experience in laparoscopic surgery decreased the surgical complication rates of total and proximal gastrectomies more than it did in distal gastrectomy over time. The 5-year overall survival rates of patients in advanced stages and those who underwent laparoscopic total gastrectomy were comparable to those reported previously.

CONCLUSIONS

Our results indicate the trends toward the expansion of laparoscopic approaches to technically demanding procedures and an increased use of laparoscopic function-preserving surgeries for patients with EGC with acceptable outcomes.

Totally laparoscopic spleen-preserving splenic hilum lymph nodes dissection in radical total gastrectomy: an omnibearing method

OBJECTIVE

To investigate the feasibility and safety of laparoscopic spleen-preserving splenic hilum lymph nodes (LNs) dissection for advanced proximal gastric cancer using an omnibearing method.

METHODS

Between August 2013 and December 2014, 16 patients with advanced proximal gastric cancer treated in Guangdong Province Hospital of Chinese Medicine, were enrolled and subsequently underwent laparoscopic radical total gastrectomy (TG) with spleen-preserving splenic hilum LNs dissection. During dissecting Nos. 10 and 11 LNs, we divided them into two parts, namely LNs anterosuperior and posterior to the splenic vessel. The clinicopathological characteristics, intraoperative outcomes and postoperative courses were retrospectively collected and analyzed in the study.

RESULTS

Laparoscopic surgery was successfully completed in all 16 patients without conversion to open surgery, and no perioperative death occurred. The mean operating time was 328.75 ± 46.96 min, and the mean estimated blood loss was 135.63 ± 62.07 ml. One patient experienced intraoperative bleeding due to the splenic vein injury which was successfully handled with laparoscopic vessel suturing, and one postoperative pulmonary infection was recorded. The mean time to first flatus was 3.56 ± 1.03 days with a mean 9.63 ± 1.50 days of postoperative hospital stay. The mean number of retrieved LNs was 28.31 ± 5.99, in which LNs anterosuperior to splenic artery was 2.88 ± 2.66 and LNs posterior was 1.38 ± 1.75.

CONCLUSION

Laparoscopic TG with spleen-preserving splenic hilum LNs dissection using an omnibearing method for advanced proximal gastric cancer was safe and technically feasible in experienced hands. Further studies in terms of its clinical significance are needed.