Robotic gastrectomy for gastric cancer

Effects of a force feedback function in a surgical robot on the suturing procedure

BACKGROUND

Currently, widely used robotic surgical systems do not provide force feedback. This study aimed to evaluate the impact and benefits of a force feedback function on the suturing procedure.

METHODS

Twenty surgeons were recruited and divided into young (Y-group, n = 11) and senior (S-group, n = 9) groups, based on their years of surgical experience. The effect of the force feedback function on suturing quality was evaluated using an objective assessment system (A-LAP mini, Kyoto Kagaku Co., Ltd., Kyoto, Japan). Each participant completed the suturing task on intestinal model sheets with the robotic contact force feedback on and off. The task accomplishment time (s), maximal force (Newton, N) applied to the robotic forceps, and quality of suturing (assessed by A-LAP mini) were recorded as performance parameters.

RESULTS

In total, the maximal force applied to the robotic forceps was significantly decreased with the robotic force feedback switched on (median [interquartile range]: 2.8 N (2.3-3.2)) as compared with when the feedback was switched off (3.4 N (2.7-4.0), P < 0.001). The contact force feedback function did not affect the objectively assessed suturing score (18 points (17.7-19.0) versus 18 points (17.0-19.0), P = 0.421). The contact force feedback function slightly shortened the task accomplishment time in the Y-group (552.5 s (466.5-832) versus 605.5 s (476.2-689.7), P = 0.851) but not in the S-group (566 s (440.2-703.5) versus 470.5 s (419.7-560.2), P = 0.164).

CONCLUSIONS

With the contact force feedback function, the suturing task was completed with a smaller maximal force, while maintaining the quality of suturing. Because the benefits are more apparent in young surgeons, robots with the contact force feedback function will facilitate the educational process in novice surgeons.

nPTD classification: an updated classification of gastric cancer location for function preserving gastrectomy based on physiological lymphatic flow

BACKGROUND

The correlation between tumor location and lymphatic flow distribution in gastric cancer has been previously reported, and PTD (Proximal - Transitional - Distal) classification was proposed. Our group updated and developed the nPTD classification.

METHOD

We retrospectively studied gastric cancer patients who underwent the dye method sentinel node biopsy from 1993 to 2020. The inclusion criteria were a single lesion type 0 cancer of ≤5 cm in the long axis, clinically node-negative, and invasion within the proper muscle layer pathologically. In this study, the distribution of dyed lymphatic flow was evaluated for each occupied area of the tumor.

RESULTS

We included 416 patients in this study. The tumors located in the watershed of the right and left gastroepiploic arteries near greater curvature had extensive lymphatic flow; therefore, a newly circular region with a diameter of 5 cm is set on the watershed of the greater curvature between P and T zone as the 'n' zone. In addition, for cancers located in the lesser P curvature, lymphatic flow to the greater curvature was not observed. Therefore, the P zone was divided into two: the lesser curvature side (PL) and the greater curvature side (PG).

CONCLUSIONS

The advantage of the nPTD classification is that it provides not only proper nodal dissection but also adequate function-preserving gastrectomy. If the tumor is localized within the PL, the proximal gastrectomy resection area can be further reduced. In contrast, for cancers located in the 'n' zone, near-total gastrectomy is required because of the extensive lymphatic flow.

Robotic-assisted gastrectomy for gastric cancer: single Western center results

A robotic approach to abdominal surgery procedures may improve postoperative outcomes compared to either open or laparoscopic approaches. The role of robotics for gastric surgery, however, is still being evaluated. A retrospective review of the prospectively maintained database for robotic gastric surgery at University of Siena between 2011 and 2020 was conducted. Data regarding surgical procedures, early postoperative outcomes, and long-term follow-up were analyzed. 38 patients underwent robotic partial or total gastrectomy. Conversion to open occurred in two patients (5.2%) due to locally advanced disease as well as difficult identification of primary lesion. Postoperative morbidity was 13.1% while no postoperative mortality was registered. The mean length of operation was 358.6 (220-650) minutes and the mean number of retrieved lymph nodes was 35.8 (range: 5-73). The median OS of all population was 70.9 months. The median 5-year OS for the patients with positive nodes was worse than that of patients without metastatic lymph nodes [51.4 months (95% CI 35.5-67.4) vs. 79.5 months (95% CI 67.1-91.8); p = 0.079]. The interesting results including postoperative morbidity as well as mortality rate, the surgical outcomes, and the 5-year OS, were to be acceptable considering the data recorded by previous studies on robotic gastrectomy. This study demonstrated that robotic gastrectomy is feasible and can be safely performed. However, further follow-up and randomized clinical trials are required to confirm the role of a robotic approach in gastric cancer surgery.

Lymph node dissection for gastric cancer: Establishment of D2 and the current position of splenectomy in Europe and Japan

Two European phase III trials comparing D1 and D2 demonstrated that D2 did not improve the overall survival and was associated with a high mortality related to splenectomy. However, a long-term follow-up study showed that the gastric cancer-related death rate was significantly higher in D1 than D2. Based on these findings, the standard surgery in Europe became D2 without pancreatico-splenectomy to prevent mortality. In contrast, the JCOG9501 phase III comparing D2 and D2 plus para-aortic nodal dissection did not showed a survival efficacy of extended lymphadenectomy, but the mortality rate was quite low in both surgeries. Subsequently, the JCOG0110 phase III study comparing D2 and spleen-preserving D2 for upper gastric cancer not invading the greater curvature clearly showed the non-inferiority of spleen preservation. Thus, spleen-preserving D2 was made the standard surgery for these tumors in Japan. However, splenectomy is often selected for complete dissection of the splenic-hilar nodes, a frequent metastatic site for upper gastric tumors invading the greater curvature. Recently, an approach involving splenic hilar nodal dissection without splenectomy has been developed.

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.

Outcomes of Gastric Resection in the Establishment of a Comprehensive Oncologic Robotic Program

BACKGROUND

Robotic-assisted gastrectomy is increasingly utilized for the treatment of gastric malignancies. However, the benefits of robotic surgery have been questioned. This study describes short-term outcomes in the establishment of a comprehensive robotic program for gastric malignancies.

MATERIALS AND METHODS

Patients who underwent robotic-assisted gastric resections between 2013 and 2018 were studied. Preoperative measures and surgical outcomes were analyzed. Finally we studied and analyzed robotic and open gastrectomy for the management of gastric adenocarcinoma (GC) at the same institution between 2000 and 2018 for quality benchmarking.

RESULTS

Forty six patients (pts.) underwent robotic-assisted gastric resections. 26 (56.5%) were male, with a median age of 62 y (range: 29-87). Pathology included GC, gastrointestinal stromal tumors, neuroendocrine tumors, metastatic lesions, and benign processes. 19 pts. underwent total gastrectomy, 16 distal gastrectomy, four subtotal gastrectomy, and seven wedge resection. Pts. undergoing distal gastrectomy and wedge resection experienced shorter operative times and length of stay than total gastrectomy (P < 0.01; P < 0.01). Four operations (8.8%) were converted to open and 13 pts (28.3%) had postoperative complications, including an 8.7% readmission rate. Median lymph nodes retrieved during total, subtotal, and distal gastrectomy were 20 (13-46), 12.5 (0-26), and 16.5 (0-34), respectively. All pts. underwent margin negative resection. Median follow-up for GC was 21 mo, and 60% of pts. received adjuvant therapy at a median of 59d (range: 23-106).

CONCLUSIONS

Robotic gastrectomy is a feasible alternative to open gastrectomy. Our results will help establish benchmarks to improve perioperative outcomes, especially length of stay and time to initiation of therapy.

Precision surgical approach with lymph-node dissection in early gastric cancer

The gravest prognostic factor in early gastric cancer is lymph-node metastasis, with an incidence of about 10% overall. About two-thirds of early gastric cancer patients can be diagnosed as node-negative prior to treatment based on clinic-pathological data. Thus, the tumor can be resected by endoscopic submucosal dissection. In the remaining third, surgical resection is necessary because of the possibility of nodal metastasis. Nevertheless, almost all patients can be cured by gastrectomy with D1+ lymph-node dissection. Laparoscopic or robotic gastrectomy has become widespread in East Asia because perioperative and oncological safety are similar to open surgery. However, after D1+ gastrectomy, functional symptoms may still result. Physicians must strive to minimize post-gastrectomy symptoms and optimize long-term quality of life after this operation. Depending on the location and size of the primary lesion, preservation of the pylorus or cardia should be considered. In addition, the extent of lymph-node dissection can be individualized, and significant gastric-volume preservation can be achieved if sentinel node biopsy is used to distinguish node-negative patients. Though the surgical treatment for early gastric cancer may be less radical than in the past, the operative method itself seems to be still in transition.

Robot-assisted distal gastrectomy with lymph node dissection for gastric cancer in a patient with situs inversus partialis: a case report with video file

BACKGROUND

Situs inversus is a rare congenital condition that is currently classified into two types: complete situs inversus (situs inversus totalis, SIT) and partial situs inversus (situs inversus partialis, SIP). In SIP patients, some organs are inverted and others are in their expected position, and individual patient variation in organ position increases surgical difficulty. Several surgeons have performed laparoscopic or robotic surgeries in situs inversus patients, but almost all were SIT patients. We report the first case, to our knowledge, of an SIP patient with gastric cancer who was successfully treated by robot-assisted distal gastrectomy (RADG) with lymph node dissection.

CASE PRESENTATION

A 64-year-old woman diagnosed with early gastric cancer on the posterior midbody of the stomach was referred to our hospital for treatment. Computed tomography showed levocardia and inverted abdominal organs without enlarged lymph nodes or distant metastases. Polysplenia syndrome, intestinal malrotation, and left-sided gallbladder were also detected. RADG with D1+ lymph node dissection and Billroth I reconstruction (delta-shaped anastomosis) were performed using robotics. Hepatopathy caused by a liver retractor and pancreatic fistula were identified during the postoperative course, and the latter was classified as grade II based on Clavien-Dindo classification. The patient was discharged 18 days after the operation.

CONCLUSIONS

Preoperative three-dimensional imaging is beneficial, and anatomical organ identification should be routinely performed, especially in SIP patients. We consider RADG a therapeutic option in SIP patients.