Minimally invasive surgery for gastric cancer: the future standard of care

Robotic vs. laparoscopic distal gastrectomy for gastric cancer: A propensity score-matched retrospective comparative study at a single institution

BACKGROUND

Although robotic surgery is becoming more widespread worldwide, it is still in its infancy. This study aimed to confirm the safety and feasibility of the induction of robotic-assisted gastric surgery at a local hospital.

METHODS

For five years, between 2016 and 2020, 42 laparoscopic and 71 robotic distal gastrectomies were performed at the same institution. Patients diagnosed with gastric cancer were retrieved from the database. Propensity score matching was performed based on covariates such as Age, Sex, BMI, the American Society of Anesthesiologists Physical Status, Tumor Location, pT, and pN. Clinicopathological characteristics, surgical performance, postoperative outcomes, and pathological data were retrospectively collected and compared by the Chi-square test, the Fisher's exact test, the Student's t-test, and the Mann-Whitney U test.

RESULTS

Billroth II reconstruction was often selected for the robotic group more than the laparoscopic group (59.4% and 15.6%, respectively). In addition, the number of lymph nodes harvested after D2 dissection tended to be more significant in the robotic group than in the laparoscopic group (52.1 ± 7.6 and 29.1 ± 3.7, respectively; p = 0.00934). The mean operative time was 271.4 ± 10.5 min for the robotic group and 220.8 ± 12.3 min for the laparoscopic group (p = 0.00005). There were no differences in short-term clinical outcomes between the two groups.

CONCLUSIONS

Although a single-center, small comparative study, the results showed that the robotic surgery group was not inferior to the laparoscopic group in feasibility and safety. Moreover, robotic surgery enables harvesting a higher number of lymph nodes, which may be more advantageous than laparoscopic surgery. This study also showed that as the surgeon gains experience with robotic surgery, its operative time becomes significantly shorter.

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.

Validation of a novel reconstruction method of laparoscopic gastrectomy for proximal early gastric cancer: a systematic review and meta-analysis

Background

Recently, a novel surgical procedure, named as laparoscopic proximal gastrectomy (LPG) with double-tract reconstruction (DTR), has been reported to provide surgical benefits in the treatment of proximal early gastric cancer (EGC) over traditional laparoscopic total gastrectomy (LTG). These benefits include a lower incidence of some surgical complications and better postoperative nutritional status. However, the number of relevant studies is still too low to validate such benefits. Therefore, this systematic review and meta-analysis aimed to assess the surgical features, complications, and postoperative nutritional status of LPG with DTR in comparison to those of LTG.

Methods

Online databases (PubMed, Web of Science, Cochrane Library, and EMBASE) were scoured for relevant studies published by April 2020. The quality assessment of the included articles was evaluated using the Newcastle-Ottawa scale. Egger’s test was utilized to assess publication bias.

Results

Nine studies (687 patients) were enrolled for this meta-analysis, and we found that LPG with DTR and LTG had similar surgical features. However, LPG with DTR was superior to LTG in the incidence of reflux syndrome [OR = 0.185; 95%CI 0.083, 0.414; P = 0.000], postoperative nutritional status (hemoglobin [WMD = − 2.326; 95%CI − 4.491, − 0.160; P = 0.035], vitamin B12 [WMD = − 13.072; 95%CI − 22.850, − 3.294; P = 0.009], and body weight [WMD = − 3.514; 95%CI − 5.579, − 1.449; P = 0.001]).

Conclusions

LPG with DTR has better performance in the incidence of reflux syndrome and postoperative nutritional status compared with LTG. This surgical procedure may therefore have more benefits for patients with proximal EGC.

Comparison of three digestive tract reconstruction methods for the treatment of Siewert II and III adenocarcinoma of esophagogastric junction: a prospective, randomized controlled study

BACKGROUND

The incidence of adenocarcinoma of esophagogastric junction (AEG) has recently risen worldwide, including in Eastern Asia. The aim of the study was to explore the short-term and long-term clinical efficacy of piggyback jejunal interposition reconstruction single-tract reconstruction (PJIRSTR), piggyback jejunal interposition reconstruction double-tract reconstruction (PJIRDTR), and total gastrectomy esophageal jejunal Roux-en-Y anastomosis (TGRY) for the treatment of Siewert II and III AEG patients.

METHODS

A total of 300 Siewert II and III AEG patients admitted to Shanxi Tumor Hospital from June 2015 to December 2017 were prospectively selected. Patients were randomly divided into PJIRSTR group (n = 98), PJIRDTR group (n = 103), and TGRY group (n = 99) using the random number table method.

RESULTS

There were no statistically significant differences in total operation time, intraoperative blood loss, time of first anal exhaust, and postoperative hospital stay among the three groups (F = 2.526, 0.457, 0.234, 0.453; P > 0.05). The reconstruction time of PJIRSTR group and PJIRDTR group was longer than that of TGRY group (P < 0.01). There were no significant differences in cases of anastomotic leakage, anastomotic bleeding, abdominal infection, incision infection, ileus, and dumping syndrome in three groups (P > 0.05). The incidence of reflux esophagitis at 3, 6, 12, and 18 months after surgery in the PJIRSTR group and the PJIRDTR group were significantly lower than TGRY group in the same period (P < 0.05). Compared with PJIRDTR group and TGRY group, PJIRSTR group had a small fluctuation range of postoperative nutrition indexes and had basically recovered to the preoperative level at 18 months. Four patients of Visick grade IV presented in TGRY group 18 months postoperatively, which was significantly higher compared with the other two groups.

CONCLUSION

Compared with PJIRDTR and TGRY, PJIRSTR can significantly reduce the incidence of postoperative reflux esophagitis and improve the long-term nutritional status of patients.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-IIR-16007733. Registered 07 November 2015 - Retrospectively registered, http://www.chictr.org.cn/searchproj.aspx.

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.

Precision medicine in gastric cancer

Gastric cancer (GC) is a complex disease linked to a series of environmental factors and unhealthy lifestyle habits, and especially to genetic alterations. GC represents the second leading cause of cancer-related deaths worldwide. Its onset is subtle, and the majority of patients are diagnosed once the cancer is already advanced. In recent years, there have been innovations in the management of advanced GC including the introduction of new classifications based on its molecular characteristics. Thanks to new technologies such as next-generation sequencing and microarray, the Cancer Genome Atlas and Asian Cancer Research Group classifications have also paved the way for precision medicine in GC, making it possible to integrate diagnostic and therapeutic methods. Among the objectives of the subdivision of GC into subtypes is to select patients in whom molecular targeted drugs can achieve the best results; many lines of research have been initiated to this end. After phase III clinical trials, trastuzumab, anti-Erb-B2 receptor tyrosine kinase 2 (commonly known as ERBB2) and ramucirumab, anti-vascular endothelial growth factor receptor 2 (commonly known as VEGFR2) monoclonal antibodies, were approved and introduced into first- and second-line therapies for patients with advanced/metastatic GC. However, the heterogeneity of this neoplasia makes the practical application of such approaches difficult. Unfortunately, scientific progress has not been matched by progress in clinical practice in terms of significant improvements in prognosis. Survival continues to be low in contrast to the reduction in deaths from many common cancers such as colorectal, lung, breast, and prostate cancers. Although several target molecules have been identified on which targeted drugs can act and novel products have been introduced into experimental therapeutic protocols, the overall approach to treating advanced stage GC has not substantially changed. Currently, surgical resection with adjuvant or neoadjuvant radiotherapy and chemotherapy are the most effective treatments for this disease. Future research should not underestimate the heterogeneity of GC when developing diagnostic and therapeutic strategies aimed toward improving patient survival.

DZNep inhibits Hif-1α and Wnt signalling molecules to attenuate the proliferation and invasion of BGC-823 gastric cancer cells

3-deazaneplanocin A (DZNep) is a histone methyltransferase inhibitor, which may cause the reactivation of silenced tumor suppressor genes in tumors to inhibit the development, metastasis and dissemination of tumor cells. However, the effects and mechanisms of its application in gastric cancer remain unclear. The present study revealed an inhibitory function of DZNep in BGC-823 cells. The cell colony, Cell Counting Kit-8 (CCK8), wound healing, Transwell and flow cytometry assays were performed, and the results demonstrated that DZNep could inhibit the proliferation, apoptosis and invasion of BGC-823 cells, and promote their apoptosis. The effects of intervention in BDC-823 cells with DZNep on the RNA and protein expression levels of hypoxia-inducible factor (Hif-1α) and Wnt/β-catenin signalling molecules were further examined using reverse transcription-quantitative PCR and western blot analysis. The results demonstrated that different concentrations of DZNep could inhibit the expression of enhancer of zeste homolog 2 (EZH2) protein, decrease the RNA and protein expression levels of Hif-1α, total β-catenin and phosphorylated-β-catenin and increase the expression levels of non-phosphorylated-β-catenin to different degrees. The results of the present study suggests that DZNep inhibits BGC-823 gastric cancer cells via the inhibition of EZH2, Hif-1α and Wnt/β-catenin signalling molecules. These results provide theoretical basis for the application of DZNep in clinical trials.

International consensus statement on robotic pancreatic surgery

The robotic surgical system has been applied to various types of pancreatic surgery. However, controversies exist regarding a variety of factors including the safety, feasibility, efficacy, and cost-effectiveness of robotic surgery. This study aimed to evaluate the current status of robotic pancreatic surgery and put forth experts' consensus and recommendations to promote its development. Based on the WHO Handbook for Guideline Development, a Consensus Steering Group* and a Consensus Development Group were established to determine the topics, prepare evidence-based documents, and generate recommendations. The GRADE Grid method and Delphi vote were used to formulate the recommendations. A total of 19 topics were analyzed. The first 16 recommendations were generated by GRADE using an evidence-based method (EBM) and focused on the safety, feasibility, indication, techniques, certification of the robotic surgeon, and cost-effectiveness of robotic pancreatic surgery. The remaining three recommendations were based on literature review and expert panel opinion due to insufficient EBM results. Since the current amount of evidence was low/meager as evaluated by the GRADE method, further randomized controlled trials (RCTs) are needed in the future to validate these recommendations.

Predictive factors for lymph node metastasis and defining a subgroup treatable for laparoscopic lymph node dissection after endoscopic submucosal dissection in poorly differentiated early gastric cancer

AIM

To investigate the predictive factors of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC); to guide the individual application of a combination of endoscopic submucosal dissection (ESD) and laparoscopic lymph node dissection (LLND) in a suitable subgroup of patients with poorly differentiated EGC.

METHODS

We retrospectively analyzed 138 patients with poorly differentiated EGC who underwent gastrectomy with lymphadenectomy between January 1990 and December 2015. The association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95% confidence interval (95%CI) were calculated. We further examined the relationship between the positive number of the significant predictive factors and the LNM rate.

RESULTS

The tumor diameter (OR = 13.438, 95%CI: 1.773-25.673, P = 0.029), lymphatic vessel involvement (LVI) (OR = 38.521, 95%CI: 1.975-68.212, P = 0.015) and depth of invasion (OR = 14.981, 95%CI: 1.617-52.844, P = 0.024) were found to be independent risk factors for LNM by multivariate analysis. For the 138 patients diagnosed with poorly differentiated EGC, 21 (15.2%) had LNM. For patients with one, two and three of the risk factors, the LNM rates were 7.7%, 47.6% and 64.3%, respectively. LNM was not found in 77 patients that did not have one or more of the three risk factors.

CONCLUSION

ESD might be sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2 cm in size and when LVI is absent upon postoperative histological examination. ESD with LLND may lead to the elimination of unnecessary gastrectomy in poorly differentiated EGC.

Presence of cancer cells in the periarterial tissues of patients with advanced gastric cancer

Lymphadenectomy with gastrectomy is considered a curative surgical treatment for gastric cancer. Periarterial connective tissue-preserving lymphadenectomy has become a common procedure following developments in laparoscopic surgery. However, the presence of cancer cells in the periarterial tissue, including neural invasion, has not been examined. In the present study, the periarterial tissues from the vessel roots of the left gastric artery (LGA) and right gastroepiploic artery (RGEA) after gastrectomy were evaluated for the presence of cancer cells. The study included 28 consecutive patients who underwent gastrectomy for gastric cancer. The vessel roots of the RGEA and LGA were obtained from surgically resected specimens and examined by two independent pathologists to determine the presence of cancer cells in the periarterial tissues. The collected specimens included 23 RGEA roots and 26 LGA roots from 28 patients. In 8 cases of early gastric cancer, no cancer cells were indicated in the periarterial tissues. By contrast, cancer cells, including neural invasion in 2 cases, were identified in the periarterial tissues from the roots of examined gastric arteries in 3/20 (15%) cases of advanced gastric cancer. Notably, all 3 cases featured multiple regional lymph node (LN) metastases. Cancer cells were detected in the perivascular tissue of the major gastric arteries from cases with advanced gastric cancer with LN metastases, suggesting the requirement for oncologic evaluation to ensure adequate vascular tissue margins and an adequate periarterial layer during lymphadenectomy.

Gastric Adenocarcinoma: A Multimodal Approach

Despite its declining incidence, gastric cancer (GC) remains a leading cause of cancer-related deaths worldwide. A multimodal approach to GC is critical to ensure optimal patient outcomes. Pretherapy fine resolution contrast-enhanced cross-sectional imaging, endoscopic ultrasound and staging laparoscopy play an important role in patients with newly diagnosed ostensibly operable GC to avoid unnecessary non-therapeutic laparotomies. Currently, margin negative gastrectomy and adequate lymphadenectomy performed at high volume hospitals remain the backbone of GC treatment. Importantly, adequate GC surgery should be integrated in the setting of a multimodal treatment approach. Treatment for advanced GC continues to expand with the emergence of additional lines of systemic and targeted therapies.

The principles of the surgical management of gastric cancer

Surgery is the only curative therapy for gastric cancer but most operable gastric cancer presents in a locally advanced stage characterized by tumor infiltration of the serosa or the presence of regional lymph node metastases. Surgery alone is no longer the standard treatment for locally advanced gastric cancer as the prognosis is markedly improved by perioperative chemotherapy. The decisive factor for optimum treatment is the multidisciplinary team specialized in gastric cancer. However, despite multimodal therapy and adequate surgery only 30% of gastric cancer patients are alive at 3 years. This article reviewed the principles of the surgical management of gastric cancer (minimally invasive or open) and how this may optimize multimodal treatment.

Robotic vs laparoscopic distal gastrectomy with D2 lymphadenectomy for gastric cancer: a retrospective comparative mono-institutional study

Background

Robotic surgery has been developed with the aim of improving surgical quality and overcoming the limitations of conventional laparoscopy in the performance of complex mini-invasive procedures. The present study was designed to compare robotic and laparoscopic distal gastrectomy in the treatment of gastric cancer.

Methods

Between June 2008 and September 2015, 41 laparoscopic and 30 robotic distal gastrectomies were performed by a single surgeon at the same institution. Clinicopathological characteristics of the patients, surgical performance, postoperative morbidity/mortality and pathologic data were prospectively collected and compared between the laparoscopic and robotic groups by the Chi-square test and the Mann-Whitney test, as indicated.

Results

There were no significant differences in patient characteristics between the two groups. Mean tumor size was larger in the laparoscopic than in the robotic patients (5.3 ± 0.5 cm and 3.0 ± 0.4 cm, respectively; P = 0.02). However, tumor stage distribution was similar between the two groups. The mean number of dissected lymph nodes was higher in the robotic than in the laparoscopic patients (39.1 ± 3.7 and 30.5 ± 2.0, respectively; P = 0.02). The mean operative time was 262.6 ± 8.6 min in the laparoscopic group and 312.6 ± 15.7 min in the robotic group (P < 0.001). The incidences of surgery-related and surgery-unrelated complications were similar in the laparoscopic and in the robotic patients. There were no significant differences in short-term clinical outcomes between the two groups.

Conclusions

Within the limitation of a small-sized, non-randomized analysis, our study confirms that robotic distal gastrectomy is a feasible and safe surgical procedure. When compared with conventional laparoscopy, robotic surgery shows evident benefits in the performance of lymphadenectomy with a higher number of retrieved and examined lymph nodes.

Risk Stratification According to the Total Number of Factors That Meet the Indication Criteria for Radical Lymph Node Dissection in Patients with Early Gastric Cancer at Risk for Lymph Node Metastasis

BACKGROUND

Extended indications for endoscopic resection for early gastric cancer (EGC) have been widely accepted. However, according to current guidelines, additional gastrectomy with lymph node dissection (LND) is recommended for patients proven to have potential risks of lymph node metastasis (LNM) on histopathological findings. The aim of this study was to elucidate the risk stratification of outcome and LNM according to the number of factors that meet the inclusion criteria for radical LND for possible LNM (LNM risk factors) in patients with negative endoscopic resection margin.

METHODS

We enrolled 511 EGC patients whose tumors did not meet the absolute or extended indications for endoscopic resection, and investigated the risk stratification of prognosis and LNM according to the total number of LNM risk factors.

RESULTS

Recurrence-free and overall survival rates were significantly higher in patients with fewer LNM risk factors for surgical indication (p = 0.0274 and 0.0002, respectively; log-rank test), and the total number of LNM risk factors and frequency of LNM were significantly correlated (p < 0.0001; Kruskal-Wallis test). When only one LNM risk factor was satisfied, the LNM ratio was 0.58 % (1/173, 95 % confidence interval 0.01-3.18).

CONCLUSION

The present study suggested the possibility of using further minimally invasive treatment strategies based on the total number of LNM risk factors.

Accuracy of diagnostic demarcation of undifferentiated-type early gastric cancer for magnifying endoscopy with narrow-band imaging: surgical cases

BACKGROUND AND AIM

The usefulness of magnifying endoscopy with narrow-band imaging (ME-NBI) in undifferentiated-type early gastric cancers (UD-type EGCs) is unclear. This study investigated the accuracy of ME-NBI in the diagnostic demarcation.

METHODS

Among UD-type EGCs that were initially surgically resected between June 2011 and August 2014 in this hospital, 74 lesions were studied that were preoperatively diagnosed with white-light imaging (WLI) or endoscopic ultrasonography as lesions for which endoscopic treatment was not indicated and found to be early gastric cancers by postoperative pathology. The demarcation line was marked on the most oral and anal sides with argon plasma coagulation using WLI and ME-NBI, and the diagnostic demarcation of cancer was defined as correct, if consistent with the results of postoperative pathology. The length of extension into the proliferative zone, distance between crypts and inflammatory cell infiltration (updated Sydney classification: USC) were compared between the correctly diagnosed and the misdiagnosed cases.

RESULTS

The diagnosis was correct in 62 cases (83.8 %). The average distance between crypts in correctly diagnosed and misdiagnosed cases was approximately 1.9 and 1.3 times, respectively, that in normal mucosa (p < 0.0001). The accuracy of diagnosis was higher when atrophy and neutrophil and monocyte infiltration were mild according to the USC (p < 0.05). The additional use of ME-NBI improved the accuracy of diagnosis by 36.5 % compared with the use of WLI alone.

CONCLUSION

The use of ME-NBI in the preoperative diagnosis of the demarcation of cancer is useful to prevent postoperative positive surgical margins.

Feasibility study on expanded indication for endoscopic submucosal dissection of intramucosal poorly differentiated early gastric cancer

AIM: To identify clinicopathological factors predictive of lymph node metastasis (LNM) in intramucosal poorly differentiated early gastric cancer (EGC), and further to expand the possibility of using endoscopic submucosal dissection (ESD) for the treatment of intramucosal poorly differentiated EGC.

METHODS: Data for 81 surgically treated patients with intramucosal poorly differentiated EGC were collected, and the association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Several clinicopathologic factors were investigated to identify predictive factors for lymph nodes metastasis, including gender, age, family history of gastric cancer, number of tumors, tumor location, ulceration, tumor size, macroscopic type, lymphatic vessel involvement, and signet-ring-cell component.

RESULTS: Tumor size (OR = 7.273, 95%CI: 1.246-29.918, P = 0.042), lymphatic vessel involvement (OR = 42.219, 95%CI: 1.923-97.052, P = 0.018) and signet-ring-cell component (OR = 17.513, 95%CI: 1.647-77.469, P = 0.034) that were significantly associated with LNM by univariate analysis, were found to be significant and independent risk factors for LNM by multivariate analysis. However, gender, age, family history of gastric cancer, number, location, ulceration and macroscopic type of tumor were found not to be associated with LNM. Of these 81 patients diagnosed with intramucosal poorly differentiated EGC, 7 (8.6%) had LNM. The LNM rates were 9.1%, 22.2% and 57.1%, respectively, in cases with one, two and three of the risk factors. There was no LNM in 54 patients without the three risk clinicopathological factors.

CONCLUSION: Tumor size, lymphatic vessel involvement and signet-ring-cell component are independently associated with the presence of LNM in intramucosal poorly differentiated EGC. Thus, these three risk factors may be used as a simple criterion to expand the possibility of using ESD for the treatment of intramucosal poorly differentiated EGC.

Dexmedetomidine improves gastrointestinal motility after laparoscopic resection of colorectal cancer: A randomized clinical trial

BACKGROUND

To investigate the effects of intraoperative application of dexmedetomidine (Dex) on early gastrointestinal motility after laparoscopic resection of colorectal cancer.

METHODS

In this prospective, randomized double-blind investigation, 60 patients who underwent laparoscopic resection of colorectal cancer were randomly allocated to receive Dex (DEX group, n = 30) or saline (CON group, n = 30). In the DEX group, Dex was loaded (1 μg/kg) before anesthesia induction and was infused (0.3 μg/kg/h) during surgery. Time to postoperative first flatus (FFL) and first feces (FFE), and time to regular diet were recorded. Serum diamine oxidase (DAO) activity and intestinal fatty acid-binding protein (I-FABP) were detected.

RESULTS

Both the time to the FFL (44.41 ± 4.51 hours vs 61.03 ± 5.16 hours, P = 0.02) and the time to the FFE (60.67 ± 4.94 hours vs 82.50 ± 6.88 hours, P = 0.014) were significantly shorter in the DEX group than the CON group. Furthermore, the time to regular diet of the DEX group was shorter than that of the CON group (76.15 ± 4.11 hours vs 91.50 ± 5.70 hours, P = 0.037). Both DAO and I-FABP increased significantly from beginning of surgery to postoperative day 1 in the CON group (2.49 ± 0.41 ng/mL vs 4.48 ± 0.94 ng/mL for DAO, P = 0.028, 1.32 ± 0.09 ng/mL vs 2.17 ± 0.12 ng/mL for I-FABP, P = 0.045, respectively), whereas no significant change was observed in the DEX group. Furthermore, patients in the DEX group had stable hemodynamics and shorter hospital stay than those in the CON group.

CONCLUSION

Dex administration intraoperatively benefits recovery of gastrointestinal motility function after laparoscopic resection of colorectal cancer with stable hemodynamics during surgery though further studies are needed to explore the mechanisms of Dex on gastrointestinal motility.

Minimally invasive surgery for upper gastrointestinal cancer: Our experience and review of the literature

Minimally invasive surgery (MIS) for upper gastrointestinal (GI) cancer, characterized by minimal access, has been increasingly performed worldwide. It not only results in better cosmetic outcomes, but also reduces intraoperative blood loss and postoperative pain, leading to faster recovery; however, endoscopically enhanced anatomy and improved hemostasis via positive intracorporeal pressure generated by CO2 insufflation have not contributed to reduction in early postoperative complications or improvement in long-term outcomes. Since 1995, we have been actively using MIS for operable patients with resectable upper GI cancer and have developed stable and robust methodology in conducting totally laparoscopic gastrectomy for advanced gastric cancer and prone thoracoscopic esophagectomy for esophageal cancer using novel technology including da Vinci Surgical System (DVSS). We have recently demonstrated that use of DVSS might reduce postoperative local complications including pancreatic fistula after gastrectomy and recurrent laryngeal nerve palsy after esophagectomy. In this article, we present the current status and future perspectives on MIS for gastric and esophageal cancer based on our experience and a review of the literature.

Is preoperative staging enough to guide lymph node dissection in clinically early gastric cancer?

BACKGROUND

Limited by the accuracy of preoperative staging, some cases of gastric cancer invading the muscularis propria (pT2) are underestimated as early gastric cancer (EGC) in the preoperative assessment. The aim of this present study was to determine prognostic factors and to propose indications for limited lymph node dissection in patients with clinically EGC (cEGC).

METHODS

Patients of cEGC (n = 2072) who were postoperatively diagnosed as pT1 (cT1pT1, n = 1858) and pT2 (cT1pT2, n = 214) from 2005 to 2009 at Seoul National University Hospital were retrospectively analyzed.

RESULTS

There was no difference in 5-year survival rate between the cT1pT1 and cT1pT2 group (95.5 % vs. 92.5 %, P = 0.059), and both groups had better overall survival than pT2 patients who were preoperatively diagnosed as locally advanced gastric cancer (cT2-4pT2), whose 5-year survival rate was 78.0 % (P < 0.001). Multivariate analysis indicated lymph node metastasis (LNM) was the independent prognostic factor for cEGC (P < 0.001). In cEGC patients, three preoperative factors, including N stage by multidetector-row computed tomography (MDCT) (P < 0.001), preoperative histological type (P < 0.001), and tumor size (P < 0.001), were associated with LNM by multivariate analysis. Regarding the possibility of LNM, low-risk (4.4 %) and high-risk (17.3 %) groups were developed based on weighted scores of the aforementioned independent three variables. Among 52 patients in the low-risk group, the extension of LNM was limited to the perigastric area.

CONCLUSIONS

Comprehensive evaluation based on MDCT, preoperative histological type, and tumor size is an effective method to predict LNM and guide tailored LN dissection for cEGC.

Simultaneous laparoscopy-assisted resection for rectal and gastric cancer

Laparoscopy-assisted surgery for either rectal or gastric cancer has been increasingly performed. However, simultaneous laparoscopy-assisted resection for synchronous rectal and gastric cancer is rarely reported in the literature. In our study, 3 cases of patients who received simultaneous laparoscopy-assisted resection for synchronous rectal and gastric cancer were recorded. The results showed that all 3 patients recovered well, with only 253 minutes of mean operation time, 57 mL of intraoperative blood loss, 5 cm of assisted operation incision, 4 days to resume oral intake, 12 days' postoperative hospital stay, and no complication or mortality. No recurrence or metastasis was found within the follow-up period of 22 months. When performed by surgeons with plentiful experience in laparoscopic technology, simultaneous laparoscopy-assisted resection for synchronous rectal and gastric cancer is safe and feasible, with the benefits of minimal trauma, fast recovery, and better cosmetic results, compared with open surgery.

Cutting edge of endoscopic full-thickness resection for gastric tumor

Recently, several studies have reported local full-thickness resection techniques using flexible endoscopy for gastric tumors, such as gastrointestinal stromal tumors, gastric carcinoid tumors, and early gastric cancer (EGC). These techniques have the advantage of allowing precise resection lines to be determined using intraluminal endoscopy. Thus, it is possible to minimize the resection area and subsequent deformity. Some of these methods include: (1) classical laparoscopic and endoscopic cooperative surgery (LECS); (2) inverted LECS; (3) combination of laparoscopic and endoscopic approaches to neoplasia with non-exposure technique; and (4) non-exposed endoscopic wall-inversion surgery. Furthermore, a recent prospective multicenter trial of the sentinel node navigation surgery (SNNS) for EGC has shown acceptable results in terms of sentinel node detection rate and the accuracy of nodal metastasis. Endoscopic full-thickness resection with SNNS is expected to become a treatment option that bridges the gap between endoscopic submucosal dissection and standard surgery for EGC. In the future, the indications for these procedures for gastric tumors could be expanded.

Defining a Subgroup Treatable for Laparoscopic and Endoscopic Cooperative Surgery in Undifferentiated Early Gastric Cancer: the Role of Lymph Node Metastasis

BACKGROUND

Recently, the use of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) and the development of laparoscopic and endoscopic cooperative surgery (LECS) have enabled either the preservation of the stomach or the minimization of the extent of partial resection. ESD has recently been practiced on a differentiated type of EGC. However, there is no clear evidence for endoscopic treatments of undifferentiated EGC. The purposes of this study are to investigate predictive factors of lymph node metastasis (LNM) in undifferentiated EGC and expand the possibility of using LECS for the treatment of undifferentiated EGC.

METHODS

Data from 116 patients with undifferentiated EGC and surgically treated were collected, and the association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95 % confidence interval (95 % CI) were calculated.

RESULTS

The tumor size (OR = 11.748, 95 % CI 2.034-62.213, P = 0.008), depth of invasion (OR = 13.928, 95 % CI 1.971-92.434, P = 0.016), and lymphatic vessel involvement (OR = 11.522, 95 % CI 2.645-59.172, P = 0.021) that were significantly associated with LNM by univariate analysis were found to be significant and independent risk factors for LNM by multivariate analysis. The LNM rate was 5.9 % (4/68) and 29.2 % (14/48) with intramucosal and submucosal undifferentiated EGC, respectively. LNM was observed in 66.7 % (2/3) of patients with both risk factors (tumor larger than or equal to 2.0 cm and the presence of lymphatic vessel involvement (LVI)), but in none of 36 patients without the two risk factors in intramucosal undifferentiated EGC. The 5-year survival rates were 88.9, 72.4, and 33.3 %, respectively, in cases with none, one, and two of the risk factors, respectively, in intramucosal undifferentiated EGC (P < 0.05).

CONCLUSIONS

ESD alone may be a sufficient treatment for intramucosal undifferentiated EGC if the tumor is less than 2.0 cm in size and when LVI is absent upon postoperative histological examination. LECS is feasible and safe for patients with undifferentiated EGC.

Current status of randomized controlled trials for laparoscopic gastric surgery for gastric cancer in China

China alone accounts for nearly 42% of all new gastric cancer cases worldwide, and gastric cancer is the third leading cause of cancer deaths in China nowadays. Without mass screening programs, unfortunately over 80% of all Chinese patients have been diagnosed as advanced diseases. As in other Asian countries, especially Japan and Korea, laparoscopic gastrectomy for the treatment of gastric cancer has gained increasingly popularity in China during the past decade. Whether laparoscopic surgery can be safely and effectively performed in the treatment of gastric cancer remains controversial, particularly with regard to curative intent in advanced diseases. Given the high incidence of these cancers, and their advanced stage at diagnosis, China has a significant interest in determining the safety and effectiveness of laparoscopic gastrectomy. A well-designed randomized controlled trial (RCT) is considered the only feasible way to provide conclusive evidence. To date, China has not played a significant role in terms of conducting RCT concerning laparoscopic surgery for gastric cancer. However, an effort has been made by the Chinese researchers, with the great help from our colleagues in neighboring countries such as Korea and Japan, through the establishment of the Chinese Laparoscopic Gastrointestinal Surgery Study Group. In this review, we present the current status of RCT for laparoscopic gastric surgery for gastric cancer in China, including published and ongoing registered RCT.

Reconstruction after proximal gastrectomy for gastric cancer in the upper third of the stomach: a review of the literature published from 2000 to 2014

Proximal gastrectomy (PG) is occasionally performed to preserve the physiological function of the remnant stomach with the aim of maintaining a gastric reservoir for patients with early gastric cancer in the upper third of the stomach. Many reconstructive procedures after PG have been reported, including esophagogastrostomy (EG), jejunal interposition, jejunal pouch interposition, and double tract. However, no general agreement exists regarding the optimal reconstructive procedure. This article reviews the current reconstructive procedures available for PG. We examined the surgical outcomes, postoperative complications, endoscopic findings, and quality of life (QOL) according to the reconstructive procedures. We found no significant difference in anastomotic leakage and anastomotic stricture among the procedures. The frequency of reflux esophagitis was higher with simple EG compared with the other reconstructive procedures. Some additional procedures, such as fundoplication, the use of a narrow gastric conduit, and placement of a gastric tube in the lower mediastinum on EG, could decrease the frequency of reflux esophagitis and reflux symptoms. These additional procedures may improve the QOL; however, the previous studies were small and could not adequately compare the reconstructive procedures. Prospective randomized controlled trials that involve a longer trial period and more institutions are needed to clarify the optimal reconstructive procedures after PG.

Effect of visceral fat area on outcomes of laparoscopyassisted distal gastrectomy for gastric cancer: subgroup analysis by gender and parameters of obesity

PURPOSE

The aim of this study was to investigate the impact of the visceral fat area (VFA) of patients with gastric cancer undergoing laparoscopic surgery on operative outcomes such as number of retrieved lymph nodes (LNs) and operative time.

METHODS

We retrospectively reviewed the medical records and the CT scans of 597 patients with gastric cancer who underwent laparoscopy assisted distal gastrectomy (LADG) with partial omentectomy and LN dissection (>D1 plus beta). Patients were stratified by gender, VFA, and body mass index (BMI), and the clinicopathologic characteristics and operative outcomes were evaluated. Multiple linear regression analysis was used to assess the effects of VFA and BMI on the number of retrieved LNs and operative time in male and female patients.

RESULTS

The mean number of retrieved LNs was significantly decreased for both male and female patients with high VFA. The operative time was significantly longer for both male and female patients with high VFA. The number of retrieved LNs had a statistically significant negative correlation with VFA in both men and women, but not with BMI. The operative time had a statistically significant positive correlation with VFA in men, whereas the operative time had a statistically significant positive correlation with BMI in women.

CONCLUSION

The preoperative VFA of male patients with gastric cancer who undergo LADG may affect the number of retrieved LNs and operative time. VFA was more useful than BMI for predicting outcomes of LADG.

Laparoscopy-assisted combined resection for synchronous gastrointestinal multiple primary cancers

BACKGROUND

Synchronous gastrointestinal multiple primary cancers (SGMPC) is infrequent. This study aimed to investigate the feasibility and outcomes of laparoscopy-assisted combined resection for SGMPC.

MATERIAL AND METHODS

We retrospectively reviewed 16 cases of SGMPC underwent either open or laparoscopy-assisted combined resection in the Third Affiliated Hospital of Sun Yat-sen University from Jan. 2005 to Jan. 2014.

RESULTS

Sixteen cases contained synchronous colon cancers (n = 10), gastric and rectal cancer (n = 5), gastric and duodenal cancer (n = 1). Either laparoscopy-assisted or open procedure was performed. Compared with the open group, the laparoscopy group presented less blood loss (77.1 ± 46.3 ml vs. 145.0 ± 75.9 ml, P = 0.047) and shorter incision length (5.2 ± 0.7 cm vs. 16.4 ± 1.9 cm, P = 0.000), while no differences in operative time (228.3 ± 38.8 min vs. 188.8 ± 47.7 min, P > 0.05) and postoperative hospital stay (10.0 ± 3.4 days vs. 12.0 ± 4.8 days, P > 0.05). Two cases of postoperative complications occurred in the open group and one case of incision infection occurred in the laparoscopy one. Upon follow-up, 2 cases of open group (50.0%) and 8 cases of laparoscopy group (66.7%) were under status of disease free survival.

CONCLUSIONS

Laparoscopy-assisted combined resection for SGMPC is feasible, safe and effective.

Is early oral feeding after gastric cancer surgery feasible? A systematic review and meta-analysis of randomized controlled trials

Aim

To assess the feasibility and safety of early oral feeding (EOF) after gastrectomy for gastric cancer through a systematic review and meta-analysis based on randomized controlled trials.

Methods

A literature search in PubMed, Embase, Web of Science and Cochrane library databases was performed for eligible studies published between January 1995 and March 2014. Systematic review was carried out to identify randomized controlled trials comparing EOF and traditional postoperative oral feeding after gastric cancer surgery. Meta-analyses were performed by either a fixed effects model or a random effects model according to the heterogeneity using RevMan 5.2 software.

Results

Six studies remained for final analysis. Included studies were published between 2005 and 2013 reporting on a total of 454 patients. No significant differences were observed for postoperative complication (RR = 0.95; 95%CI, 0.70 to 1.29; P = 0.75), the tolerability of oral feeding (RR = 0.98; 95%CI, 0.91 to 1.06; P = 0.61), readmission rate (RR = 1; 95%CI, 0.30 to 3.31; P = 1.00) and incidence of anastomotic leakage (RR = 0.31; 95%CI, 0.01 to 7.30; P = 0.47) between two groups. EOF after gastrectomy for gastric cancer was associated with significant shorter duration of the hospital stay (WMD = −2.36; 95%CI, −3.37 to −1.34; P<0.0001) and time to first flatus (WMD = −19.94; 95%CI, −32.03 to −7.84; P = 0.001). There were no significant differences in postoperative complication, tolerability of oral feeding, readmission rates, duration of hospital stay and time to first flatus among subgroups stratified by the time to start EOF or by partial and total gastrectomy or by laparoscopic and open surgery.

Conclusions

The result of this meta-analysis showed that EOF after gastric cancer surgery seems feasible and safe, even started at the day of surgery irrespective of the extent of the gastric resection and the type of surgery. However, more prospective, well-designed multicenter RCTs with more clinical outcomes are needed for further validation.

Totally laparoscopic total gastrectomy for gastric cancer: literature review and comparison of the procedure of esophagojejunostomy

There has been a recent increase in the use of totally laparoscopic total gastrectomy (TLTG) for gastric cancer. However, there is no scientific evidence to determine which esophagojejunostomy (EJS) technique is the best. In addition, both short- and long-term oncological results of TLTG are inconsistent. We reviewed 25 articles about TLTG for gastric cancer in which at least 10 cases were included. We analyzed the short-term results, relationships between EJS techniques and complications, long-term oncological results, and comparative study results of TLTG. TLTG was performed in a total of 1170 patients. The mortality rate was 0.7%, and the short-term results were satisfactory. Regarding EJS techniques and complications, circular staplers (CSs) methods were significantly associated with leakage (4.7% vs. 1.1%, p < 0.001) and stenosis (8.3% vs. 1.8%, p < 0.001) of the EJS as compared with the linear stapler method. The long-term oncological prognosis was acceptable in patients with early gastric cancers and without metastases to lymph nodes. Although TLTG tended to increase surgical time compared with open total gastrectomy and laparoscopy-assisted total gastrectomy, it reduced intraoperative blood loss and was expected to shorten postoperative hospital stay. TLTG is found to be safer and more feasible than open total gastrectomy and laparoscopy-assisted total gastrectomy. At present, there is no evidence to encourage performing TLTG for patients with advanced gastric cancer from the viewpoint of long-term oncological prognosis. Although the current major EJS techniques are CS and linear stapler methods, in this review, CS methods are significantly associated with leakage and stenosis of the EJS.

Meta-analysis of pylorus-preserving gastrectomy for middle-third early gastric cancer

BACKGROUND

Pylorus-preserving gastrectomy (PPG) has been performed to reduce postprandial symptoms for some early gastric cancer (EGC) cases. The aim of this study was to evaluate the possible advantages after PPG for middle-third EGC in comparison with distal gastrectomy.

MATERIALS AND METHODS

We searched Medline, Embase, and Science Citation Index Expanded for relevant studies. Statistical analyses were conducted to calculate the summary weighted mean differences (WMDs) and odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs) using random-effects models.

RESULTS

We identified 15 nonrandomized controlled trials (16 studies) with 1774 patients, which consisted of 11 studies for conventional PPG (CPPG) versus conventional distal gastrectomy (CDG) and 5 studies for laparoscopy-assisted PPG (LAPPG) versus laparoscopy-assisted distal gastrectomy (LADG). Meta-analysis of CPPG versus CDG revealed that CPPG had the advantage of prevention of early dumping syndrome (OR=0.18; 95% CI 0.12, 0.27), gastritis (OR=0.19; 95% CI 0.07, 0.53), duodenal juice reflux (OR=0.20; 95% CI 0.06, 0.66), and regaining of weight (WMD=3.53; 95% CI 2.34, 4.72). However, the incidence of gastric stasis was higher in the CPPG group than in the CDG group (OR=1.70; 95% CI 1.13, 2.57). Meta-analysis of LAPPG versus LADG revealed that LAPPG shortened the operation time (WMD=-21.12; 95% CI -31.33, -10.90) and did not increase the occurrence of postoperative complication (OR=0.72; 95% CI 0.41, 1.27).

CONCLUSIONS

With the benefits of prevention of early dumping syndrome, duodenal juice reflux, gastritis, and regaining of weight, PPG can be an excellent option for middle-third EGC.

Novel laparoscopic procedure for treating proximal early gastric cancer: laparoscopy-assisted pylorus-preserving nearly total gastrectomy

PURPOSE

Pylorus-preserving nearly total gastrectomy (PPNTG) is a function-preserving gastrectomy for treating proximal early gastric cancer that prevents rapid gastric emptying and reflux. In this report, we present a surgical technique for performing laparoscopy-assisted PPNTG (LAPPNTG).

METHODS

The resection of the stomach was similar to that during conventional total gastrectomy, with the key difference being that the pyloric cuff was preserved to a length of 3-4 cm. Compared with standard total gastrectomy, the lymph node dissection along the right gastric vessels and the infrapyloric vessels were omitted. Reconstruction was performed with a jejunal interposition that was 30 cm in length, with preservation of the marginal vessels in a retrocolic fashion.

RESULTS

Thirteen patients with cT1 cN0 proximal gastric cancer underwent LAPPNTG at our institution. The median length of the operation and estimated blood loss were 329 min and 138 ml, respectively. All resected specimens had tumor-free margins, and the median number of removed lymph nodes was 40. There were no serious postoperative complications and no patients underwent conversion to laparotomy.

CONCLUSIONS

Performing LAPPNTG with a jejunal interposition is feasible and might be an appropriate treatment for proximal early gastric cancer.

Is the rate of postoperative complications following laparoscopy-assisted gastrectomy higher in elderly patients than in younger patients?

Background

With an increase in life expectancy, very elderly patients are presenting with gastric cancer more commonly than ever. The present study retrospectively analyzed the surgical outcomes of laparoscopy-assisted gastrectomy for gastric cancer in the young, elderly, and very elderly age groups.

Methods

The study group consisted of 1,055 patients who underwent laparoscopy-assisted gastrectomy between February 2002 and December 2012. We divided these patients into three groups; group 1 (young age, <65 years), group 2 (elderly age, 65–74 years), and group 3 (very elderly age, ≥75 years).

Results

There were statistical differences in the rates of postoperative complications among the three groups (P = 0.008). However, when assessed according to the severity of postoperative complications based on the Clavien-Dindo classification, there was no statistical difference among the three groups (P = 0.562).

Conclusions

Laparoscopy-assisted gastrectomy for gastric cancer can be performed in very elderly patients. In analyzing studies of elderly patients with postoperative complications following the procedure, not only should the rate of postoperative complications be taken into consideration, but also the severity of any postoperative complications.

Current role of minimally invasive approaches in the treatment of early gastric cancer

Despite declining incidence, gastric cancer remains one of the most common cancers worldwide. Early detection in population-based screening programs has increased the number of cases of early gastric cancer, representing approximately 50% of newly detected gastric cancer cases in Asian countries. Endoscopic mucosal resection and endoscopic submucosal dissection have become the preferred therapeutic techniques in Japan and Korea for the treatment of early gastric cancer patients with a very low risk of lymph node metastasis. Laparoscopic and robotic resections for early gastric cancer, including function-preserving resections, have propagated through advances in technology and surgeon experience. The aim of this paper is to discuss the recent advances in minimally invasive approaches in the treatment of early gastric cancer.

Readmissions following elective radical total gastrectomy for early gastric cancer: a case-controlled study

BACKGROUND

Readmission after gastrectomy is one of the factors that reflect quality of life. Therefore, we analyzed the several factors related to readmissions after total gastrectomy for early gastric cancer.

METHODS

From January 2002 through December 2009, 102 consecutive patients who underwent radical total gastrectomy for early gastric cancer were enrolled in this study. We evaluated the incidence, cause, time point, and type of treatment for readmission after discharge; we compared the readmission and non-readmission groups in regard to clinicopathologic features and postoperative outcomes.

RESULTS

The readmission rate during the five years after total gastrectomy was 22 of 102 (21.6%). The most common cause for readmission was esophagojejunostomy stricture (5 cases). The treatment given for 31 readmissions included 23 conservative therapies, 3 radiologic or endoscopic interventions, and 5 re-operations. No significant differences were detected in the clinicopathologic feature, postoperative outcomes, or 5-year survival rates between the readmission and non-readmission group. No specific risk factor was found to be associated with readmission.

CONCLUSION

Although we could not determine a specific risk factor associated with readmission after radical total gastrectomy, prevention of readmission by evaluating the causes and treatments after radical total gastrectomy can improve the patient's quality of life.

Comparison of three different minimally invasive procedures of distal gastrectomy for Nonoverweight patients with T1N0-1 gastric cancer

Laparoscopic-assisted distal gastrectomy has recently come to be a standard procedure for the treatment of early gastric cancer (1 - 5) in select patients. The minimal invasiveness associated with laparoscopic procedures for the resection of gastrointestinal cancer has been repeatedly explained in part by the short incision that is required. (6 - 11) We used two different approaches to perform distal gastrectomies for the resection of gastric cancer as minimally invasive alternatives to a standard laparoscopic approach prior to our surgical team's complete mastery of the skills required for laparoscopic oncological surgery for gastric cancer. (9 , 12) If the minimal invasiveness associated with laparoscopic-assisted gastrectomy can be explained by the small incision, a gastrectomy via a small incision without the use of a pneumoperitoneum may provide a similar outcome in patients. However, to our knowledge, such a comparison has not been previously made. We compared the minimal invasiveness of three different approaches (minilaparotomy, minilaparotomy approach with laparoscopic assistance, and standard laparoscopic-assisted approach) to performing a distal gastrectomy for T1N0-1 gastric cancer in nonoverweight patients (body mass index, ≤ 25 kg/m(2)) performed within a limited study period.

Is routine preoperative spirometry necessary in elderly patients undergoing laparoscopy-assisted gastrectomy?

Objectives

To identify predictors of postoperative pulmonary complications (PPCs) in patients aged ≥60 years who underwent laparoscopy-assisted gastrectomy (LAG), and to examine the value of preoperative spirometry to predict PPCs.

Methods

Patients with preoperative spirometric results who underwent LAG were retrospectively studied. Spirometry included four parameters: forced expiratory volume in 1 s; functional vital capacity; mean forced expiratory flow during middle of functional vital capacity; peak expiratory flow rate.

Results

Of 213 patients, overall incidence of PPCs was 19.2%. Abnormal spirometry findings were not identified as an independent predictor of PPCs using multivariate logistic regression analysis. Age was found to be the only independent predictor of PPCs out of all variables evaluated. Separate assessment of individual spirometric parameters using receiver-operating curve analyses indicated poor diagnostic accuracy.

Conclusions

Preoperative spirometry was not reliably predictive of PPCs, either as combined or individual parameters, in patients aged ≥60 years who underwent LAG. These results do not support routine use of spirometry to stratify risk of PPCs in this surgical population.

Laparoscopic gastrectomy for gastric cancer

Laparoscopic gastrectomy for gastric cancer is rapidly becoming popular because of the technical developments and the accumulated data of laparoscopic surgery in gastric cancer patients. The aim of this review is to present the current body of evidence and to highlight controversial issues of laparoscopic gastrectomy for gastric cancer. Laparoscopic distal gastrectomy (LDG) provides better or comparable outcomes compared to conventional open distal gastrectomy (ODG) in terms of short-term results. The long-term survival of LDG is expected to be comparable to that of ODG in early-stage gastric cancer, and an ongoing Korean multicenter randomized controlled trial (KLASS-01) will provide more clear evidence. Laparoscopic total gastrectomy is still selectively performed compared to LDG, and there is still debate on the safety of the laparoscopic esophagojejunostomy technique. Laparoscopic pylorus-preserving gastrectomy seems to be preferred for early gastric cancer in the middle third of the stomach in terms of functional advantages and comparable oncologic outcome. Evidence for LDG for advanced gastric cancer is still insufficient and the issue of lack of generalization still remains, even after ongoing multicenter randomized controlled trials have revealed clinical evidence. Laparoscopic sentinel node navigation surgery is still experimental and the surgical procedure has yet to be standardized. Robotic gastrectomy is feasible for early gastric cancer in terms of similar outcome, but is much more expensive in comparison to laparoscopic surgery. Its benefit over the conventional laparoscopic gastrectomy has not yet been proven.

Detection of metastatic lymph nodes using 5-aminolevulinic acid in patients with gastric cancer

BACKGROUND

Precise diagnosis of lymph node metastases is essential to select therapeutic strategy for patients with gastric cancer, and rapid intraoperative diagnosis is useful for performing less invasive surgery. In this study, we focused on a known photosensitizer, 5-aminolevulinic acid (5-ALA), and examined the feasibility of 5-ALA-induced protoporphyrin IX (PpIX) fluorescence to detect metastatic foci in excised lymph nodes of patients with gastric cancer.

METHODS

A total of 144 lymph nodes obtained from 14 gastric cancer patients were examined. The patients were administered 5-ALA orally before surgery. Excised lymph nodes were cut in half and observed by fluorescence microscopy. The diagnostic results were compared to those of the routine histopathological examination.

RESULTS

Observed red fluorescence of PpIX was identical to the metastatic focus, with 84 % accuracy. Twelve non-metastatic lymph nodes showed unexpected PpIX accumulation to lymphoid follicles, but these could be discriminated based on their characteristic fluorescence patterns. With incorporation of this morphological consideration, this method demonstrated good diagnostic power with 92.4 % accuracy. On the quantitative analysis using the signal intensity ratio of red to the sum of red, green, and blue (R/(R + G + B) ratio) as an index corresponding to red fluorescence of PpIX, metastatic lymph nodes showed significantly higher value than non-metastatic lymph nodes (p < 0.0001). The area under the curve was calculated as 0.832 throughout Receiver operating characteristic analysis.

CONCLUSIONS

Our results demonstrated that 5-ALA-induced fluorescence diagnosis is a simple and safe method and is a potential candidate for a novel rapid intraoperative diagnostic method applicable to clinical practice.

Defining a subgroup treatable for laparoscopic surgery in poorly differentiated early gastric cancer: the role of lymph node metastasis

OBJECTIVE

The present study aims to identify the clinicopathologic factors predictive of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC) and to expand the possibility of using laparoscopic surgery for the treatment of poorly differentiated EGC.

METHODS

Data from 70 cases of poorly differentiated EGC treated with surgery were collected. The association between clinicopathologic factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses.

RESULTS

Univariate analysis showed that tumor size, depth of invasion, and lymphatic vessel involvement (LVI) were the significant and independent risk factors for LNM (all P<0.05). The LNM rates were 6.9%, 45.5%, and 60.0%, respectively. There was no LNM in 25 patients without the above three risk factors.

CONCLUSIONS

Laparoscopic surgery is a sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2.0 cm in size and when LVI is absent upon postoperative histological examination.

Defining a subgroup treatable for laparoscopic surgery in poorly differentiated early gastric cancer: the role of lymph node metastasis

Objective

The present study aims to identify the clinicopathologic factors predictive of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC) and to expand the possibility of using laparoscopic surgery for the treatment of poorly differentiated EGC.

Methods

Data from 70 cases of poorly differentiated EGC treated with surgery were collected. The association between clinicopathologic factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses.

Results

Univariate analysis showed that tumor size, depth of invasion, and lymphatic vessel involvement (LVI) were the significant and independent risk factors for LNM (all P<0.05). The LNM rates were 6.9%, 45.5%, and 60.0%, respectively. There was no LNM in 25 patients without the above three risk factors.

Conclusions

Laparoscopic surgery is a sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2.0 cm in size and when LVI is absent upon postoperative histological examination.

Laparoscopic surgery for advanced gastric cancer: current status and future perspectives

Laparoscopic gastrectomy has been widely accepted especially in patients with early-stage gastric cancer. However, the safety and oncologic validity of laparoscopic gastrectomy for advanced gastric cancer are still being debated. Since the late 90s', we have been engaged in developing a stable and robust methodology of laparoscopic radical gastrectomy for advanced gastric cancer, and have established laparoscopic distinctive technique for suprapancreatic lymph node dissection, namely the outermost layer-oriented medial approach. In this article, We present the development history of this method, and current status and future perspectives of laparoscopic gastrectomy for advanced gastric cancer based on our experience and a review of the literature.

Tissue engineering of the stomach

Tissue engineering combines engineering principles with the biological sciences to create functional replacement tissues. The underlying principle of tissue engineering is that isolated cells combined with biomaterials can form new tissues and organs in vitro and in vivo. This review focuses on stomach tissue engineering, which is a promising approach to the treatment of gastric cancer, the fourth most common malignancy in the world and the second-leading cause of cancer mortality worldwide. Although gastrectomy is a reliable intervention to achieve complete removal of cancer lesions, the limited capacity for food intake after resection results in lower quality of life for patients. To address this issue, we have developed a tissue-engineered stomach to increase the capacity for food intake by creating a new food reservoir. We have transplanted this neo-stomach as a substitute for the original native stomach in a rat model and confirmed functional adaptation. Furthermore, we have demonstrated the feasibility of transplanting a tissue-engineered gastric wall patch in a rat model to alleviate the complications after resection of a large area of the gastric wall. Although progress has been achieved, significant challenges remain to bring this approach to clinical practice. Here, we summarize our work and present the state of the art in stomach tissue engineering.

Laparoscopy-assisted distal gastrectomy for early gastric cancer in the elderly

PURPOSE

With an increase in life expectancy, more elderly patients are presenting with gastric cancer. As a result it is yet be resolved whether laparoscopy assisted distal gastrectomy is a suitable treatment for elderly patients with early gastric cancer. This study retrospectively compared surgical outcomes of laparoscopy assisted distal gastrectomy between elderly and nonelderly patients with gastric cancer.

MATERIALS AND METHODS

The study group was comprised of 316 patients who underwent laparoscopy assisted distal gastrectomy between April 2005 and December 2010. Of these patients, 93 patients whose ages were 65 years or more were compared with 223 patients who were younger.

RESULTS

There were no differences in the short term outcome or minor complication rate between the elderly patients and the nonelderly patients. The hospital stay was significantly longer and the major complication rate was significantly higher for the elderly patients compared with nonelderly patients.

CONCLUSIONS

Laparoscopy assisted distal gastrectomy for early gastric cancer in the elderly patients had comparable operation time and blood loss with the nonelderly group. However, the safety and advantage of laparoscopy assisted distal gastrectomy in the elderly patients need to be further studied in higher volume trials.

Totally laparoscopic versus open gastrectomy for gastric cancer: a matched cohort study

BACKGROUND

The role of laparoscopic surgery for the treatment of gastric cancer is still controversial, particularly in terms of oncologic efficacy. The aim of this study was to compare short-term outcomes of laparoscopic and open resection for gastric cancer at a single Western institution.

SUBJECTS AND METHODS

This study was designed as a matched cohort study from a prospective gastric cancer database. Forty-one patients undergoing laparoscopic gastrectomy for gastric cancer between June 2008 and January 2012 were matched with 41 patients undergoing open gastrectomy in the same time period. Patient pairing was done according to age, gender, type of gastrectomy (subtotal or total), and tumor stage via a randomized statistical method. The short-term outcomes and oncologic adequacy of the laparoscopic and open procedures were compared. A D2 lymph node dissection was performed in the majority of patients in both groups.

RESULTS

The two study groups were similar with respect to patient and tumor characteristics. Laparoscopic procedures were associated with a decreased blood loss (118.7 versus 312.4 mL, P<.005), incidence of surgery-unrelated complications (3 versus 9 patients, P<.05), and duration of hospital stay (8.1 versus 11.5 days, P<.05) but increased operative time for both subtotal (223.5 versus 158.2 minutes, P<.001) and total (298.1 versus 185.5 minutes, P<.001) gastrectomies. The mean number of retrieved lymph nodes after D2 dissection was similar: 30.0 for laparoscopic and 29.7 for open patients.

CONCLUSIONS

Within the limitations of a nonrandomized analysis, this study shows that the laparoscopic approach is a safe and oncologically adequate option for the treatment of gastric cancer, which compares favorably with open gastrectomy in short-term outcomes.

Risk clinicopathological factors for lymph node metastasis in poorly differentiated early gastric cancer and their impact on laparoscopic wedge resection

AIM: To investigate the predictive factors of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC), and enlarge the possibility of using laparoscopic wedge resection (LWR).

METHODS: We retrospectively analyzed 85 patients with poorly differentiated EGC who underwent surgical resection between January 1992 and December 2010. The association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95%CI were calculated. We further examined the relationship between the positive number of the three significant predictive factors and the LNM rate.

RESULTS: In the univariate analysis, tumor size (P = 0.011), depth of invasion (P = 0.007) and lymphatic vessel involvement (P < 0.001) were significantly associated with a higher rate of LNM. In the multivariate model, tumor size (OR = 7.125, 95%CI: 1.251-38.218, P = 0.041), depth of invasion (OR = 16.624, 95%CI: 1.571-82.134, P = 0.036) and lymphatic vessel involvement (OR = 39.112, 95%CI: 1.745-123.671, P = 0.011) were found to be independently risk clinicopathological factors for LNM. Of the 85 patients diagnosed with poorly differentiated EGC, 12 (14.1%) had LNM. The LNM rates were 5.7%, 42.9% and 57.1%, respectively in cases with one, two and three of the risk factors respectively in poorly differentiated EGC. There was no LNM in 29 patients without the three risk clinicopathological factors.

CONCLUSION: LWR alone may be sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2.0 cm in size, and when lymphatic vessel involvement is absent at postoperative histological examination.

Laparoscopic gastrectomy for cancer

Gastric cancer is common worldwide. Tumor location and disease stage differ between Asian and Western countries. Western patients often have higher BMIs and comorbidities that may make laparoscopic resections challenging. Multiple trials from Asian countries demonstrate the benefits of laparoscopic gastrectomy for early gastric cancer while maintaining equivalent short-term and long-term oncologic outcomes compared with open surgery. The outcomes of laparoscopy seem to offer equivalent results to open surgery. In the United States, laparoscopic gastrectomy remains in its infancy and is somewhat controversial. This article summarizes the literature on the epidemiology, operative considerations and approaches, and outcomes for laparoscopic gastrectomy.