Impact of preoperative prealbumin levels on long-term prognosis in patients with gastric cancer after gastrectomy: a retrospective cohort study

BACKGROUND

The relationship between preoperative prealbumin levels and long-term prognoses in patients with gastric cancer after gastrectomy has not been fully investigated. This study clarified the effect of preoperative prealbumin levels on the long-term prognosis of patients with gastric cancer after gastrectomy.

METHODS

This retrospective cohort study included consecutive patients who underwent radical gastrectomy for primary pStage I-III gastric cancer and whose preoperative prealbumin levels were measured between May 2006 and March 2017. Participants were categorized according to their preoperative prealbumin levels into high (≥22 mg/dL), moderate (15-22 mg/dL), and low (<15 mg/dL) groups. The overall survival (OS) in the three groups was compared using the log-rank test, and prognostic factors were identified using Cox proportional hazards regression analysis.

RESULTS

The median follow-up duration was 66 months. Of 4732 patients, 3649 (77.2%) were classified as high, 925 (19.6%) as moderate, and 158 (3.3%) as low. Lower prealbumin levels were associated with poorer prognoses (P < 0.001). Multivariate analysis showed that prealbumin levels of 15-22 mg/dL [hazard ratio (HR): 1.576, 95% confidence interval (CI): 1.353-1.835, P < 0.001] and <15 mg/dL (HR: 1.769, 95% CI: 1.376-2.276, P < 0.001) were independent poor prognostic factors for OS. When analyzed according to the cause of death, prealbumin levels were associated with other-cause survival, but not cancer-specific survival.

CONCLUSIONS

Preoperative prealbumin levels correlated with OS in patients with gastric cancer after gastrectomy; the lower the prealbumin level, the worse is the prognosis. Prealbumin levels may be associated with other-cause survival.

Equal short-term outcomes of intracorporeal mechanical gastrogastrostomy in laparoscopic pylorus-preserving gastrectomy for cT1N0 gastric cancer in the middle stomach compared with the extracorporeal hand-sewing method

BACKGROUND

Intracorporeal mechanical gastrogastrostomy (IMG) techniques have recently been developed and their short-term safety was presented in their initial evaluation. However, whether they are comparable to extracorporeal hand-sewing gastrogastrostomy (EHG) remains unclear. The aim of the study is to establish the safety of IMG in totally laparoscopic pylorus-preserving gastrectomy (TLPPG) compared to EHG in laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG).

METHODS

We retrospectively analyzed the short-term outcomes of patients with middle-third early gastric cancer who underwent LAPPG or TLPPG between 2005 and 2022. The primary objective of this study was to evaluate the non-inferiority of IMG to EHG in terms of safety, with the primary endpoint being the risk difference in anastomosis-related complications (ARCs). The sample size required to achieve a statistical power of 80% for the non-inferiority test was 971 with a one-sided alpha level of 5% and non-inferiority of 5%.

RESULTS

The analysis included a total of 1,021 patients who underwent LAPPG or TLPPG during the study period. Among them, 488 patients underwent EHG, while 533 underwent IMG. The incidences of ARCs were 11.3% and 11.4% in EHG and IMG, respectively. The observed difference in incidence was 0.0017 (90% confidence interval - 0.0313 to 0.0345), which statistically demonstrated the non-inferiority of IMG to EHG in the incidence of ARCs. Among other complications, the incidence of wound infection in IMG was lower than that in EHG.

CONCLUSION

IMG is safe regarding ARCs compared with EHG. These results will encourage surgeons to introduce IMG for patients with early middle gastric cancer.

Clinical Impact of Polyglycolic Acid Mesh to Reduce Pancreas-Related Complications After Minimally Invasive Surgery for Gastric Cancer: A Propensity Score Matching Analysis

PURPOSE

Prevention of pancreas-related complications after gastric cancer surgery is critical. Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated.

MATERIALS AND METHODS

This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors.

RESULTS

A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy.

CONCLUSIONS

The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

Adequate gross resection margin length ensuring pathologically complete resection in gastrectomy for gastric cancer: A systematic review and meta-analysis

Aim

A positive resection margin (RM) is associated with poor survival after gastrectomy for gastric cancer (GC). However, the adequate RM length to avoid a positive RM remains controversial. We performed a systematic review to examine the RM length required to avoid a positive RM in gastrectomy for GC.

Methods

This systematic review involved all relevant articles identified in PubMed, the Cochrane Library, Web of Science, and ClinicalTrials.gov until August 2023. The incidence of a positive RM related to the RM length and the possible incidence of a positive RM estimated from the discrepancy between the gross and pathological RM length were evaluated. The Newcastle-Ottawa Scale was used to quantify study quality.

Results

Thirteen studies involving 8983 patients were analyzed. Investigation of the incidence of a positive RM in relation to the RM length showed that a proximal RM length of 6 cm guaranteed a negative RM in gastrectomy. Analyses of the possible incidence of a positive RM revealed that a negative RM would be guaranteed if the proximal RM length was 6 cm in distal gastrectomy, if the esophageal resection length was 2 cm in total gastrectomy for GC without esophageal invasion and 2.5 cm in total or proximal gastrectomy for GC with esophageal invasion or esophagogastric junction cancer, and if the distal RM length was 4 cm in proximal gastrectomy for early GC.

Conclusions

The adequate RM lengths to ensure a pathologically negative RM in each type of gastrectomy for GC were herein suggested.

Perioperative or neoadjuvant chemotherapy for locally advanced gastric or gastroesophageal junction cancer: from independent evidence in the West, the East, and Japan to global collaboration

The survival outcome of patients with locally advanced gastric or gastroesophageal junction (G/GEJ) cancer remains unsatisfactory, and improvements in survival and recurrence remain urgent issues for clinicians worldwide. Prior to the 2000s, locally advanced G/GEJ was a different disease between the West and the East regarding diagnosis, surgery, and prognosis. However, recent advances in medical oncology have set the stage for harmonization. Herein, this review highlights clinical trials of perioperative or neoadjuvant chemotherapy conducted during the past two decades to provide insights into future directions. We focused on pivotal clinical trials of perioperative or neoadjuvant chemotherapy for patients with locally advanced G/GEJ cancer. We paid special attention to the indication and oncological outcomes of perioperative or neoadjuvant chemotherapy. The attempts to investigate the optimal treatment strategy for locally advanced G/GEJ cancer over the past 20 years have resulted in a global consensus on the necessity of perioperative or neoadjuvant chemotherapy, although there have been different circumstances regarding treatment for G/GEJ cancer among the West, the East other than Japan, and Japan. Two randomized global phase III trials, the KEYNOTE-585 and MATTHERHORN, were successfully accomplished for a common indication. Furthermore, perioperative immunotherapy suggested a new indication with molecular biomarkers such as microsatellite status or PD-L1 status beyond the conventional tumor-lymph node-metastasis (TNM) staging system. Global studies provide the stage for discussing the future optimal indication of neoadjuvant chemotherapy, opening the door for future global collaborations to better treat patients with locally advanced G/GEJ cancer.

Long-term impact of sarcopenia in older patients undergoing gastrectomy for gastric cancer: a systematic review and meta-analysis

Background

Sarcopenia is an inevitable problem in older patients. After gastrectomy, patients often have an inadequate dietary intake and easily fall into sarcopenia. However, the impact of preoperative sarcopenia on long-term outcomes after gastrectomy has not been analyzed.

Methods

A systematic review was conducted for all relevant articles identified on PubMed, the Cochrane Library, Web of Science, and ClinicalTrials.gov until April 2023. Adjusted hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using the fixed or random effects model according to the heterogeneity. The Newcastle-Ottawa Scale was used to quantify study quality.

Results

Seven studies involving 1,831 patients aged ≥65 years who underwent gastrectomy for gastric cancer were analyzed. Four hundred twelve patients (22.5%) were diagnosed with sarcopenia. The analysis showed that preoperative sarcopenia was significantly associated with poor overall survival (OS) (HR =1.93; 95% CI:1.60-2.34; P<0.001). Two of the included studies also showed that preoperative sarcopenia was significantly correlated with disease-related survival: one with disease-specific survival (DSS) (HR =4.00; 95% CI: 1.20-13.3, P=0.024) and the other with non-cancer specific survival (HR =3.27; 95% CI: 1.61-6.67; P=0.001). Furthermore, sarcopenic patients experienced more severe complications than non-sarcopenic patients (OR =1.80; 95% CI: 1.10-2.95; P=0.019).

Conclusions

This meta-analysis suggested that preoperative sarcopenia is useful as a prognostic factor of impaired OS in older patients after gastrectomy. Preoperative evaluation and intervention for skeletal muscle loss should be considered. Further studies of sarcopenic impact on disease-related survival are required.

Robotic Splenic Vessels Preserving Distal Pancreatectomy in a Post-Distal Gastrectomy Patient

BACKGROUND

The optimal procedure during distal pancreatectomy (DP) for patients who have undergone distal gastrectomy (DG) remains unclear. Several papers on remnant gastric ischemia have reported that the preserved splenic vessels are essential for the proximal remnant stomach.1-4 We evaluated the outcomes of DP for post-DG patients in our hospital and introduced robotic splenic vessels preserving DP (R-SPDP).

METHODS

Postoperative short-term outcomes of DP for post-DG patients during 2014 and 2021 were evaluated. Next, R-SPDP was performed for a post-DG patient with the intention of preserving the remnant stomach safely. The double bipolar method was used to dissect the adhesions around the splenic vessels.5,6 The splenic artery was clamped at the root side to prevent bleeding.7 All short gastric arteries and veins, which were the main feeders of the remnant stomach, were preserved and resection was completed. After resection, the indocyanine green (ICG) fluorescence angiography confirmed blood flow in the short gastric arteries and veins and good return blood flow to the splenic vein.8 RESULTS: Of four patients (50.0%, of 8 DP patients) in whom the remnant stomach was preserved, one conventional DP case had poor ICG perfusion and presented with remnant stomach ischemia postoperatively. The R-SPDP case with good ICG perfusion had a total operation time of 371 minutes and intraoperative blood loss of 10 mL. The oral diet was started on postoperative Day 3, and the postoperative course was uneventful.

CONCLUSIONS

R-SPDP can be a good option for post-DG patients to preserve the remnant stomach safely.

Randomized phase II study comparing neoadjuvant 5-fluorouracil/oxaliplatin/docetaxel versus docetaxel/oxaliplatin/S-1 for patients with type 4 or large type 3 gastric cancer

Macroscopic type 4 and large type 3 gastric cancer, mostly overlapping with scirrhous or linitis plastica type, exhibit a highly invasive nature and show unfavorable prognosis after curative surgery, even with adjuvant chemotherapy. A randomized phase III trial (JCOG0501) failed to demonstrate a survival advantage of neoadjuvant chemotherapy with S-1 plus cisplatin for this population. The current authors initiated a randomized phase II study comparing neoadjuvant chemotherapy with 5-fluorouracil/oxaliplatin/docetaxel versus docetaxel/oxaliplatin/S-1 for type 4 and large type 3 gastric cancer. 76 patients are planned to be enrolled over two years. The primary end point is the proportion of patients with a pathological response (grade 1b or higher) and secondary end points include overall survival and adverse events. Clinical Trial Registration: jRCTs031230231 (rctportal.niph.go.jp).

Relationship between antithrombotic drugs and postoperative outcomes in patients with gastric cancer after gastrectomy: a propensity matching analysis

BACKGROUND

As there is no consensus on the impact of antithrombotic drugs on post-gastrectomy outcomes in gastric cancer patients, this study aimed to investigate the impact of antithrombotic drugs on postoperative outcomes in these patients after gastrectomy.

METHODS

Patients with Stage I-III primary gastric cancer who underwent radical gastrectomy between April 2005 and May 2022 were included. We performed propensity score matching to adjust for patient background and compared bleeding complications. Multivariate analysis with logistic regression analysis was performed to identify risk factors associated with bleeding complications.

RESULTS

Of the 6798 patients, 310 (4.6%) were in the antithrombotic group and 6488 (95.4%) were in the non-antithrombotic group. Twenty-six patients (0.38%) experienced bleeding complications. After matching, the number of patients in each group was 300, with insignificant differences in any factor. A comparison of postoperative outcomes showed no difference in bleeding complications (P = 0.249). In the antithrombotic group, 39 (12.6%) continued drugs, and 271 (87.4%) discontinued them before surgery. After matching, there were 30 and 60 patients, respectively, with no differences in patient background. A comparison of postoperative outcomes showed no differences in bleeding complications (P = 0.551). In multivariate analysis, antithrombotic drug use and continuation of antiplatelet agents were not risk factors for bleeding complications.

CONCLUSION

Antithrombotic drugs and its continuation may not worsen bleeding complications in patients with gastric cancer after radical gastrectomy. Bleeding complications were rare, and further studies are needed on risk factors for bleeding complications in larger databases.

Oncological impact of unexpected horizontal tumor spread in gastric cancer that requires total gastrectomy

BACKGROUND

Gastric cancer often exhibits discrepancies between the gross and pathological tumor boundaries, and the degree of discrepancy may be a tumor characteristic. However, whether these discrepancies influence oncological outcomes remains unclear.

METHODS

The data of patients who underwent total gastrectomy for gastric cancer from 2005 to 2018 were collected. A new parameter, ΔPM, which corresponds to the length of the discrepancy between the gross and pathological proximal boundaries, was calculated and the patients were divided into two groups: patients with long ΔPM and those with short ΔPM. Oncological outcomes were compared between the two groups.

RESULTS

A length of 8 mm was determined as the cutoff value for long or short ΔPM. Tumor size, growth pattern, pathological type, depth, and esophageal invasion were associated with ΔPM > 8 mm. Overall survival of the ΔPM > 8 mm group was significantly worse than that of the ΔPM ≤ 8 mm group (5-year overall survival: 58% vs 78%; p < 0.0001). Multivariate analysis revealed that ΔPM > 8 mm was an independent risk factor for poor survival and peritoneal metastasis. The likelihood ratio test revealed a significant interaction between pT status and ΔPM (p = 0.0007). Circumferential involvement and gross esophageal invasion were poorer survival factors in the ΔPM > 8 mm group.

CONCLUSIONS

ΔPM > 8 mm is related to several clinicopathological characteristics and is an independent risk factor for poorer survival and peritoneal metastasis but not local recurrence. ΔPM > 8 mm combined with circumferential involvement or esophageal invasion is associated with relatively poor survival outcomes.

Perioperative TAS-118 plus oxaliplatin in patients with locally advanced gastric cancer: APOLLO-11 study

BACKGROUND

We investigated the feasibility of perioperative chemotherapy with S-1 and leucovorin (TAS-118) plus oxaliplatin in patients with locally advanced gastric cancer.

METHODS

Patients with clinical T3-4N1-3M0 gastric cancer received four courses of TAS-118 (40-60 mg/body, orally, twice daily for seven days) plus oxaliplatin (85 mg/m2, intravenously, day one) every two weeks preoperatively followed by gastrectomy with D2 lymphadenectomy, followed by postoperative chemotherapy with either 12 courses of TAS-118 monotherapy (Step 1) or eight courses of TAS-118 plus oxaliplatin (Step 2). The primary endpoints were completion rates of preoperative chemotherapy with TAS-118 plus oxaliplatin and postoperative chemotherapy with TAS-118 monotherapy (Step 1) or TAS-118 plus oxaliplatin (Step 2).

RESULTS

Among 45 patients enrolled, the preoperative chemotherapy completion rate was 88.9% (90% CI 78.0-95.5). Major grade ≥ 3 adverse events (AEs) were diarrhoea (17.8%) and neutropenia (8.9%). The R0 resection rate was 95.6% (90% CI 86.7-99.2). Complete pathological response was achieved in 6 patients (13.3%). Dose-limiting toxicity was not observed in 31 patients receiving postoperative chemotherapy (Step 1, n = 11; Step 2, n = 20), and completion rates were 90.9% (95% CI 63.6-99.5) for Step 1 and 80.0% (95% CI 59.9-92.9) for Step 2. No more than 10% of grade ≥ 3 AEs were observed in  patients receiving Step 1. Hypokalaemia and neutropenia occurred in 3 and 2 patients, respectively, receiving Step 2. The 3-year recurrence-free and overall survival rates were 66.7% (95% CI 50.9-78.4) and 84.4% (95% CI 70.1-92.3), respectively.

CONCLUSIONS

Perioperative chemotherapy with TAS-118 plus oxaliplatin with D2 gastrectomy is feasible.

Anatomical Position of the Pancreas as a Risk Factor for Pancreatic Fistula after Laparoscopic Gastrectomy for Gastric Cancer

BACKGROUND

Laparoscopic gastrectomy is more frequently associated with postoperative pancreatic fistula than is open gastrectomy. We assumed that compression of the pancreas with various devices to obtain a proper operative view is associated with the higher incidence of PF in LG and that the extent of the compression differs depending on the anatomical position of the pancreas. The present study aimed to elucidate the correlation between the anatomical position of the pancreas and PF after LG for gastric cancer.

METHODS

Patients who underwent LG for gastric cancer from 2005 to 2019 were retrospectively reviewed. Two anatomical parameters representing the height of the slope looking down the celiac artery from the top of the pancreas (P-A length) and the steepness of the slope (UP-CA angle) were measured in computed tomography sagittal projections. The correlation between PF and (1) P-A length, (2) UP-CA angle, and (3) other clinicopathological factors was analyzed using a logistic regression model.

RESULTS

Among 3485 patients, grade ≥ II PF was observed in 140 (4.0%) patients. The UP-CA angle [odds ratio (OR), 2.472; 95% confidence interval (CI), 1.725-3.543; P < 0.001], a high BMI (OR 2.339; 95% CI 1.634-3.348; P < 0.001), and male sex (OR 2.602; 95% CI 1.590-4.257; P < 0.001) were independently correlated with grade ≥ II PF.

CONCLUSIONS

The present study identified a significant correlation between anatomical position of the pancreas and PF after LG. High BMI and male sex were also significantly correlated with PF after LG.

Optimal resection of gastric bronchogenic cysts based on anatomical continuity with adherent gastric muscular layer: A case report

BACKGROUND

Bronchogenic cysts are congenital lesions requiring radical resection because of malignant potential. However, a method for the optimal resection of these cysts has not been completely elucidated.

CASE SUMMARY

Herein, we presented three patients with bronchogenic cysts that were located adjacent to the gastric wall and resected laparoscopically. The cysts were detected incidentally with no symptoms and the preoperative diagnosis was challenging to obtain via radiological examinations. Based on laparoscopic findings, the cyst was attached firmly to the gastric wall and the boundary between the gastric and cyst walls was difficult to identify. Consequently, resection of cysts alone caused cystic wall injury in Patient 1. Meanwhile, the cyst was resected completely along with a part of the gastric wall in Patient 2. Histopathological examination revealed the final diagnosis of bronchogenic cyst and revealed that the cyst wall shared the muscular layer with the gastric wall in Patients 1 and 2. In Patient 3, the cyst was located adjacent to the gastric wall but histopathologically originated from diaphragm rather than stomach. All the patients were free from recurrence.

CONCLUSION

The findings of this study state that a safe and complete resection of bronchogenic cysts required the adherent gastric muscular layer or full-thickness dissection, if bronchogenic cysts are suspected via pre- and/or intraoperative findings.

A sandwiching method that simplifies hepatic left lateral segment inversion to secure an optimal surgical view around the esophageal hiatus in laparoscopic and robotic gastrectomy for upper gastric and esophagogastric junction cancers

PURPOSE

In laparoscopic surgery for upper gastric and esophagogastric junction (EGJ) cancer, it is important to achieve optimal exposure of the esophageal hiatus to secure an appropriate workspace. In recent years, hepatic left lateral segment (HLLS) inversion has been used to achieve an optimal surgical field. We present a simple technique to perform a modified HLLS inversion.

METHODS

As a simple modified method, suturing a 2-0 straight needle to the peritoneum of the round ligament and pulling it to the outside of the abdominal cavity, the falciform, left triangular, and coronary ligaments were dissected. The HLLS was inverted by moving it to the right through the space of the transected falciform ligament. By ligating the thread through the round ligament, the HLLS was sandwiched between the rest of the liver and abdominal wall. The short-term surgical outcomes of patient who underwent simple modified HLLS inversion were retrospectively reviewed.

RESULTS

This study investigated consecutive 24 patients who underwent laparoscopic proximal and total gastrectomies using the simple modified HLLS inversion technique between June 2021 and April 2022. This series of procedures could be completed in approximately 16 min. A Nathanson liver retractor was used in three patients due to difficulties in completing the HLLS inversion in our institution. Postoperative serum liver enzyme levels indicated there was a small effect on the liver.

CONCLUSIONS

The simple modified HLLS inversion technique may be a safe and useful procedure and can provide an enhanced surgical field during laparoscopic surgery for upper gastric and EGJ cancers.

Reflux Esophagitis After Laparoscopic Pylorus-Preserving Gastrectomy for Gastric Cancer

BACKGROUND

Laparoscopic pylorus-preserving gastrectomy (LPPG) is performed for cT1N0 gastric cancer as a function-preserving surgery, but reflux esophagitis can develop as a mid- to long-term complication postoperatively. We aimed to clarify the incidence rate of this complication and the factors correlated with it.

METHODS

Patients with gastric cancer who underwent LPPG between 2005 and 2017 were analyzed. Postoperative reflux esophagitis was evaluated with esophagogastroduodenoscopy; patients were diagnosed as having reflux esophagitis with erosive esophagitis using the modified Los Angeles classification. The incidence rate of postoperative reflux esophagitis was estimated; factors correlated with postoperative reflux esophagitis were analyzed using the logistic regression model.

RESULTS

During the study period, 813 patients underwent LPPG for gastric cancer, and 127 (15.6%) of them developed grade B or more severe postoperative reflux esophagitis. The factors correlated with postoperative reflux esophagitis were male sex (odds ratio, 2.68; 95% confidence interval, 1.77-4.05; P < 0.001), preoperative grade A reflux esophagitis (odds ratio, 3.05; 95% confidence interval, 1.28-7.27; P = 0.012), body mass index of ≥ 23 kg/m² at 1 year postoperatively (odds ratio, 2.18; 95% confidence interval, 1.34-3.53; P = 0.002), postoperative hiatal hernia (odds ratio, 4.35; 95% confidence interval, 2.35-8.04; P < 0.001), and long-term stasis (odds ratio, 1.58; 95% confidence interval, 1.01-2.47; P = 0.044).

CONCLUSIONS

Careful attention should be paid in performing LPPG and in postoperative management after LPPG for gastric cancer patients with those risk factors.

Clinical outcomes of palliative treatment for gastric bleeding from incurable gastric cancer

PURPOSE

Deciding palliative treatment for gastric bleeding from incurable gastric cancer (IGC) is worrying considering different patient situations and the lack of comprehensive assessment of palliative treatment. We evaluated the clinical outcomes and prognostic factors after palliative treatment for gastric bleeding from IGC.

METHODS

We enrolled 48 consecutive patients with gastric bleeding from IGC who underwent palliative surgery (PS) or palliative radiotherapy (PRT).

RESULTS

Of the 48 patients, 23 underwent PS and 25 received PRT. More patients who had an Eastern Cooperative Oncology Group-Performance Status (ECOG-PS) ≥ 2 or who received chemotherapy underwent PRT than underwent PS. Severe complications were observed in 2 (8.6%) patients after PS. After PRT, 22 patients achieved hemostasis (88%), but rebleeding was found in 10 (40%). Chemotherapy was introduced after palliative treatment for 21 (91.3%) patients in the PS group and 17 (68%) patients in the PRT group. The median survival time (MST) of patients with and without chemotherapy after PS was 12.5 and 3.1 months, respectively (p ≤ 0.001), while the MST of patients with and without chemotherapy after PRT was 6.5 and 1.6 months (p < 0.001). Multivariate analyses identified ECOG-PS, tumor size, and chemotherapy after palliative treatment as independent risk factors.

CONCLUSIONS

Palliative treatment strategies for gastric bleeding should be determined with consideration of the general condition, previous chemotherapy, and chemotherapy after palliative treatment.

A continuous muscle-sparing advantage of pylorus-preserving gastrectomy for older patients with cT1N0M0 gastric cancer in the middle third of the stomach

In older patients with cT1N0M0 gastric cancer in the middle third of the stomach, LPPG has advantages over LDGB1 in maintaining skeletal muscle mass.

BACKGROUND

Laparoscopic pylorus-preserving gastrectomy (LPPG) for early gastric cancer in the middle third of the stomach is expected to be an alternative procedure to laparoscopic distal gastrectomy (LDG). However, whether LPPG is safe and more useful than LDG in older patients is unclear because of their comorbidities and organ dysfunctions.

METHODS

We retrospectively analyzed the data of consecutive patients aged 75 or over who underwent LDG with Billroth I reconstruction (LDGB1) or LPPG for cT1N0M0 gastric cancer in the middle third of the stomach between 2005 and 2019. After propensity score matching was used to improve the comparability between the LDGB1 and LPPG groups, we compared surgical and postoperative nutritional outcomes, including the postoperative trends of bodyweight (%BW) and skeletal muscle index (%SMI).

RESULTS

A total of 132 patients who underwent LDGB1 (n = 88) and LPPG (n = 44) were collected for this study. No significant difference in postoperative complications was observed. The total protein levels after LPPG were significantly higher than those after LDGB1 for 4 postoperative years. Both %BW and %SMI after LPPG were significantly maintained compared with those after LDGB1 during the first year after surgery. For the subsequent years, %BW after LPPG became similar to that after LDGB1, while %SMI after LPPG was significantly larger than LDGB1 continuously.

CONCLUSIONS

LPPG has a great advantage in maintaining the postoperative skeletal muscle mass as well as the nutritional parameters of older patients. LPPG is expected to be an alternative to LDG in older patients.

Advantages of Function-Preserving Gastrectomy for Older Patients With Upper-Third Early Gastric Cancer: Maintenance of Nutritional Status and Favorable Survival

PURPOSE

The incidence of early gastric cancer is increasing in older patients alongside life expectancy. For early gastric cancer of the upper third of the stomach, laparoscopic function-preserving gastrectomy (LFPG), including laparoscopic proximal gastrectomy (LPG) and laparoscopic subtotal gastrectomy (LSTG), is expected to be an alternative to laparoscopic total gastrectomy (LTG). However, whether LFPG has advantages over LTG in older patients remains unknown.

MATERIALS AND METHODS

We retrospectively analyzed data of consecutive patients aged ≥75 years who underwent LTG, LPG, or LSTG for cT1N0M0 gastric cancer between 2005 and 2019. Surgical and nutritional outcomes, including blood parameters, percentage body weight (%BW) and percentage skeletal muscle index (%SMI) were compared between LTG and LPG or LSTG. Survival outcomes were also compared between LTG and LFPG groups.

RESULTS

A total of 111 patients who underwent LTG (n=39), LPG (n=48), and LSTG (n=24) were enrolled in this study. To match the surgical indications, LTG was further categorized into "LTG for LPG" (LTG-P) and "LTG for LSTG" (LTG-S). No significant differences were identified in the incidence of postoperative complications among the procedures. Postoperative nutritional parameters, %BW and %SMI were better after LPG and LSTG than after LTG-P and LTG-S, respectively. The survival outcomes of LFPG were better than those of LTG.

CONCLUSIONS

LFPG is safe for older patients and has advantages over LTG in terms of postoperative nutritional parameters, body weight, skeletal muscle-sparing, and survival. Therefore, LFPG for upper early gastric cancer should be considered in older patients.

Successful open radical gastrectomy for locally advanced or metastatic gastric cancer patients who suffered from coronavirus disease 2019 during preoperative chemotherapy: a report of three cases

Background

According to previous reports, in patients with preoperative coronavirus disease 2019 (COVID-19) infection, mortality is increased if they undergo surgery within 6 weeks of diagnosis. However, the optimal timing and preoperative examination for gastrectomy with a previous COVID-19 infection are still controversial. We experienced three cases in which patients successfully underwent open radical gastrectomy following preoperative chemotherapy even though they developed COVID-19 infection during the chemotherapy.

Case presentation

Case 1: A 58-year-old man with locally advanced gastric cancer caught COVID-19 during preoperative chemotherapy comprising 5-fluorouracil, calcium folate, oxaliplatin, and docetaxel. Although the patient had specific lung shadows indicating COVID-19 infection and deep venous thrombosis in the lower extremities, he underwent distal gastrectomy 10 weeks after the COVID-19 diagnosis. He had a good postoperative course. Case 2: A 56-year-old man with gastric cancer and lymph node and peritoneal metastasis caught COVID-19 during palliative chemotherapy comprising S-1, oxaliplatin, and trastuzumab. He underwent total gastrectomy as conversion surgery 8 weeks after COVID-19 infection. His postoperative course was uneventful. Case 3: A 55-year-old man with gastric cancer and paraaortic lymph node and liver metastases caught COVID-19 during S-1 and oxaliplatin treatment as neoadjuvant chemotherapy. He underwent distal gastrectomy, paraaortic lymph node sampling, and partial hepatectomy 8 weeks after COVID-19 infection although he had residual lung shadows and deep venous thrombosis in the lower extremities. He had an uneventful postoperative course.

Conclusions

Computed tomography for preoperative evaluation was performed for all three patients and revealed that lung shadows remained post-COVID-19 infection. Despite this finding, the patients had good operative courses and were discharged as planned. Surgery after 7 weeks from the diagnosis of COVID-19 infection can be performed safely even when patients are post-chemotherapy and have residual lung findings and deep venous thrombosis. This report may contribute to the development of a consensus on performing safe gastrectomy for advanced gastric cancer in patients previously infected with COVID-19.

Excellent oncological outcomes besides short-term safety of laparoscopic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumor

Background and study aims  Laparoscopic and endoscopic cooperative surgery (LECS) for gastric submucosal tumor was developed as a type of minimal local resection and is now widely used in Asian countries. However, the oncological safety of LECS for gastric gastrointestinal stromal tumor (GIST) remains unclear. LECS has potential oncology-related problems that may influence survival outcomes. Furthermore, the feasibility and safety of LECS have not yet been fully established. Patients and methods  Patients who were intended to undergo LECS for gastric GIST from 2006 to 2020 were retrospectively selected. The indication for LECS was determined according to the guidelines. The completion of LECS, complications, and survival outcomes of the patients were analyzed. Results  Two hundred fifty-nine patients were eligible in this study. According to intraoperative findings, 44 patients underwent local resection without luminal endoscopic procedures. Of the remaining 215 patients, 213 completely underwent LECS, which corresponds to a completion rate of 99.1 %. Six patients (2.8 %) had postoperative complications of Clavien-Dindo classification grade II or higher. Delayed gastric emptying was most commonly found in four patients (1.9 %). Old age ( P  = 0.0349), female sex ( P  = 0.0095), tumor located in the lesser curvature ( P  = 0.0015), and large tumor diameter ( P  = 0.0232) were significantly more common in patients with complications. The 3-year overall and disease-specific survival rates were 99 % and 100 %, respectively, in 215 patients who were intended to undergo LECS. Conclusions  Despite several oncological concerns, LECS for gastric GIST is oncologically safe besides a feasible and safe procedure in the short-term.

Minimum resection length to ensure a pathologically negative distal margin and the preservation of a larger remnant stomach in proximal gastrectomy for early upper gastric cancer

BACKGROUND

In proximal gastrectomy (PG), a longer distal margin (DM) length should be maintained to obtain a pathologically negative DM. However, a shorter DM length is preferred to preserve a large remnant stomach for favorable postoperative outcomes. Evidence regarding the minimum DM length to ensure a pathologically negative DM is useful.

METHODS

Patients who underwent PG or total gastrectomy for cT1N0M0 gastric cancer limited to the upper third were enrolled. A new parameter, ΔDM, which corresponded to the pathological extension distal to the gross tumor boundary towards the resection stump, was evaluated. The maximum ΔDM, which is the length ensuring a pathologically negative DM, was first determined. Furthermore, the possible incidences of pathologically positive DM were calculated for each pathological type and clinical tumor (cTumor) size.

RESULTS

Of 361 patients eligible for this study, 190 and 171 were assigned to differentiated (Dif) and undifferentiated types (Und), respectively. The maximum ΔDM was 30 and 40 mm in Dif and Und, respectively. Considering a correlation between cTumor size and ΔDM, and possible incidences of pathologically positive DM, 10, 20, and 30 mm were the minimal gross DM lengths in Dif when cTumor size was ≤ 15 mm, > 15 and ≤ 50 mm, and > 50 mm, respectively. In Und, the incidences of pathologically positive DM were 0.59% and 2.3% for gross DM lengths of 30 and 20 mm, respectively.

CONCLUSION

The minimum DM lengths to ensure a pathologically negative DM in PG are proposed according to the pathological type of early upper gastric cancer.

Virulence plasmids in clinical isolates of Rhodococcus equi from sick foals in the Netherlands

Clinical samples from 123 foals with suspected rhodococcosis submitted to the Veterinary Microbiological Diagnostic Centre of the Faculty of Veterinary Medicine between 1993 and 2006 were tested for the presence of the virulence gene vapA. Of the 123 samples, 120 were vapA-positive and 3 vapA-negative Rhodococcus equi were isolated. The 120 vapA-positive R. equi were isolated from 70 tracheal wash, 19 lung tissues, 7 lymph nodes, 6 synovial fluids, 13 abscesses or pus and single isolates from the uterus, gut, cerebrospinal fluid, abdomen fluid and faeces. Of the 120 isolates, 46 were from Dutch warmblood horses, 23 from Friesian horses, 14 from Trotters, 4 from Holsteiners, 3 from Arab breed, 2 from ponies, 1 from a Welsh pony and 27 from undefined breed horses. Using plasmid profile analysis of the 120 isolates, 117 isolates contained the 85-kb type I plasmid, 2 contained the 87-kb type I plasmid and 1 contained the novel 52-kb non-mobilizable virulence plasmid reported recently. These results showed that the virulent R. equi strains harbouring a virulence plasmid of 85-kb type I or 87-kb type I, which have been detected in clinical isolates from five European countries, are widespread in the Netherlands. This is the first report of plasmid types of clinical R. equi isolates in the Netherlands.

Minimum Esophageal Resection Length to Ensure Negative Proximal Margin in Total Gastrectomy for Gastric Cancer: A Retrospective Study

Objective

To identify the minimum length of esophageal resection to ensure a pathologically negative proximal margin (PM) in total gastrectomy for gastric cancer.

Background

In total gastrectomy, a certain esophageal length is resected to obtain a pathologically negative PM because of the possibility of unexpected pathological esophageal invasion. However, a recommendation regarding the esophageal transection site in total gastrectomy has not been established.

Methods

The data of patients who underwent total gastrectomy for gastric cancer from 2005 to 2018 were collected. We evaluated the length of unexpected pathological esophageal invasion (esophageal ΔPM) in each type of disease and each location of the gross proximal tumor boundary (PB) using the length between the PB and the esophagogastric junction (PB-EGJ length).

Results

Of the 1005 patients eligible for this study, 277, 196, and 532 had cT1, cT2-4 expansive (Exp), and cT2-4 infiltrative (Inf) growth patterns, respectively. In cT1 and Exp, no unexpected pathological esophageal invasion occurred when the PB-EGJ length was >1 cm, whereas pathological esophageal invasion occurred in 20.0% of cT1 and 32.7% of Exp when the PB-EGJ length was ≤1 cm. The esophageal ΔPM was <1 cm. In Inf, no unexpected pathological esophageal invasion occurred when the PB-EGJ length was >3 cm, whereas pathological esophageal invasion occurred in 17.4% of patients when the PB-EGJ length was ≤3 cm. The esophageal ΔPM was <2 cm.

Conclusions

New recommendations regarding the esophageal resection length required to ensure a pathologically negative PM in total gastrectomy are herein proposed.

Impact of preoperative endoscopy for predicting treatment response and prognosis in patients with gastric cancer after neoadjuvant chemotherapy

Background and study aims  Response evaluation criteria in solid tumors (RECIST) have been the gold standard to preoperatively predict treatment response and prognosis in patients with gastric cancer (GC) after neoadjuvant chemotherapy (NAC); however, methods for patients without evaluable lesions by RECIST are not yet confirmed. The aim of this study was to assess the utility of preoperative endoscopy for predicting treatment response and prognosis in patients with GC after NAC. Patients and methods  This retrospective study included 105 patients with initially resectable GC who underwent NAC followed by surgical treatment. Preoperative factors for predicting treatment response and survival outcomes were analyzed. Results  The number of patients classified as responders using preoperative endoscopic assessment, RECIST, and postoperative pathological evaluation were 25 (23.8 %), 28 (26.7 %), and 18 (17.1 %), respectively. Forty-three patients (41 %) were classified as non-targeted disease only, and their treatment responses were not evaluable by RECIST. Multivariate analysis identified endoscopic response as an independent preoperative factor to predict postoperative histological treatment response (odds ratio = 4.556, 95 % CI = 1.169-17.746, P  = 0.029). Endoscopic treatment response was the only independent preoperative predictive factor for overall survival (OS) (hazard ratio = 0.419, 95 % confidence interval (CI) = 0.206-0.849, P  = 0.016). Further, endoscopic treatment response was available for 33 patients (76.7 %) with non-targeted disease only, which showed significantly different OS between endoscopic responders (80.0 %) and non-responders (43.5 %) ( P  = 0.025). Conclusions  Endoscopic evaluation was an independent preoperative factor to predict treatment response and prognosis in patients with GC after NAC. Endoscopic assessment may be especially valuable for patients who could not be assessed by RECIST.

Increased Rate of Serum Prealbumin Level after Preoperative Enteral Nutrition as an Indicator of Morbidity in Gastrectomy for Gastric Cancer with Outlet Obstruction

BACKGROUND

Preoperative malnutrition is believed to contribute to increased postoperative complications. Preoperative serum prealbumin level was reported to be a predictor of nutritional status and postoperative complications after gastrointestinal surgery, including gastrectomy. Gastric outlet obstruction caused by gastric cancer leads to insufficient nutritional status. However, the impact of preoperative enteral nutrition using naso-jejunal feeding tubes for patients with gastric outlet obstruction is not fully understood.

METHODS

From July 2010 to June 2020, 50 patients with gastric cancer-induced outlet obstruction who underwent gastrectomy following preoperative enteral nutrition via feeding tube were included. We investigated the relationship between changes in nutritional status after preoperative enteral nutrition and postoperative complications. Postoperative complications were defined as grade ≥II based on the Clavien-Dindo classification.

RESULTS

The median period of preoperative enteral nutrition was 10 days. The median increase rate of the serum prealbumin level was 10.5% (interquartile range, 0.63-38.2%), and patients with an increase rate ≥ 10% were defined as the elevated group. Postoperative morbidity was significantly higher in the non-elevated group (P = 0.0031). Univariate and multivariate analyses showed that an increased rate of the serum prealbumin level was an independent risk factor of postoperative complications for patients with gastric outlet obstruction caused by gastric cancer (P = 0.0025 and P = 0.009, respectively).

CONCLUSIONS

Preoperative enteral nutrition improved the serum prealbumin level of patients with gastric cancer-induced outlet obstruction, and an increased rate of prealbumin can be an indicator of sufficient preoperative enteral nutrition and decreased postoperative morbidity.

Risk factors and oncological impact of positive resection margins in gastrectomy for cancer: are they salvaged by an additional resection?

BACKGROUND

The situation of positive resection margins (PRMs) varies notably between Western and Asian countries. In the West, PRMs are associated with advanced disease and R1, whereas in Asia, PRMs are also considered in early disease because stomach preservation was recently prioritized. Furthermore, PRMs are usually resected to obtain R0. However, the oncological impact of PRMs and additional resection remains unclear. The aim of this study is to evaluate the oncological impact of PRMs in laparoscopic gastrectomy (LG) for clinical stage (cStage) I gastric cancer.

METHODS

A total of 2121 patients who underwent LG for cStage I gastric cancer between 2007 and 2015 were enrolled. Survival outcomes were compared between patients with PRMs (group P) and those without (group N). Furthermore, prognostic factors were analyzed using multivariate analysis.

RESULTS

Twenty-seven patients (1.3%) had PRMs. Patients in group P had upper and more advanced disease, and the 5-year relapse-free survival (RFS) rate was worse in group P compared with group N (76.3% vs. 95.1%, P = 0.003). The 5-year RFS of patients with pT2 or deeper (pT2-4) disease in group P was significantly worse than that of patients in group N (66.7% vs. 89.5%, P = 0.030) although that of patients with pT1 was not. Likelihood ratio tests showed that there was a significant interaction between pT status and PRM (P = 0.005).

CONCLUSION

PRM in cStage I gastric cancer is associated with advanced upper disease. It remains an independent prognostic factor in pT2-4 disease even after an additional resection to obtain R0.

Is proximal gastrectomy indicated for locally advanced cancer in the upper third of the stomach?

AIM

To treat upper third gastric cancer, proximal gastrectomy (PG), a function-preserving procedure, is recommended for early lesions when at least half the distal stomach can be preserved, while total gastrectomy (TG) is standard for locally advanced lesions. Oncological feasibility, when applying PG for such lesions, remains unknown.

METHODS

We reviewed patients undergoing TG for clinical (c) T2-T4 upper third gastric cancer between 2006 and 2015. Preoperative tumor locations were further classified into the cardia, fornix, and gastric body based on endoscopic findings. The metastatic rate and therapeutic value index for lymph node (LN) dissection were determined, and characteristics of patients with distal LN (No. 4d, 5, and 6) metastasis (DLNM) were reviewed. In addition, patients with pathological tumor invasion to the middle third (M) region were investigated.

RESULTS

We studied 167 patients. There were 8 (4.8%) with DLNM and 41 (24.6%) with pathological tumor invasion to the M region. As to regional stations, therapeutic indices for LN dissection at stations No. 4d, 5, 6, and 12a were zero or extremely low. No DLNM was detected in cT2 lesions or cT3/T4 lesions located within the cardia and/or the fornix. In addition, none of the lesions located within the cardia and/or the fornix by preoperative endoscopy extended to the M region in the pathological specimen.

CONCLUSIONS

For upper third gastric cancer, PG without No. 12a dissection might be acceptable for cT2-T4 lesions located within the cardia and/or the fornix when considering the risk of DLNM and cancer-positivity in the distal stump.

Short- and long-term oncological outcomes of totally laparoscopic gastrectomy versus laparoscopy-assisted gastrectomy for clinical stage I gastric cancer

BACKGROUND

Totally laparoscopic gastrectomy (TLG), which involves a complete intracorporeal gastric transection and the creation of an anastomosis, has been gradually adopted. However, a potential limitation of intracorporeal transection is the lack of tactile feedback, and whether this limitation influences oncological outcomes is unclear. The aim of this study is to evaluate the short- and long-term oncological safety of TLG using endoscopy-guided intracorporeal gastric transection for clinical stage (cStage) I gastric cancer.

METHODS

A total of 1875 consecutive patients who underwent laparoscopic gastrectomy for cStage I gastric cancer between January 2007 and March 2015 were enrolled in this study. Marking clips were preoperatively placed and a transection line was determined by perceiving it tactually in laparoscopy-assisted gastrectomy (LAG) or endoscopically in TLG. After propensity score matching, 1366 patients (683 each for LAG and TLG groups) were selected to primarily test the non-inferiority of TLG to that of LAG for relapse-free survival (RFS).

RESULTS

In the propensity-matched population, the 5-year RFS rates of the LAG and TLG groups were 94.3% (95% confidence interval (CI) 92.2-95.8%), and 95.6% (95% CI 93.8-96.9%), respectively. The hazard ratio (TLG/LAG) was 0.77 (95% CI 0.48-1.24, P for non-inferiority < 0.01). There were no significant differences in the recurrence profiles. The incidence of the remnant of marking clips or tumor tissue did not differ (LAG: 1.0% vs. TLG: 1.9%, P = 0.177).

CONCLUSIONS

TLG using preoperative markings and intraoperative endoscopic guidance provides cStage I gastric cancer patients with comparable oncological outcomes to the conventional method.

Preliminary prospective study of real-time post-gastrectomy glycemic fluctuations during dumping symptoms using continuous glucose monitoring

BACKGROUND

Although dumping symptoms constitute the most common post-gastrectomy syndromes impairing patient quality of life, the causes, including blood sugar fluctuations, are difficult to elucidate due to limitations in examining dumping symptoms as they occur.

AIM

To investigate relationships between glucose fluctuations and the occurrence of dumping symptoms in patients undergoing gastrectomy for gastric cancer.

METHODS

Patients receiving distal gastrectomy with Billroth-I (DG-BI) or Roux-en-Y reconstruction (DG-RY) and total gastrectomy with RY (TG-RY) for gastric cancer (March 2018-January 2020) were prospectively enrolled. Interstitial tissue glycemic profiles were measured every 15 min, up to 14 d, by continuous glucose monitoring. Dumping episodes were recorded on 5 patient-selected days by diary. Within 3 h postprandially, dumping-associated glycemic changes were defined as a dumping profile, those without symptoms as a control profile. These profiles were compared.

RESULTS

Thirty patients were enrolled (10 DG-BI, 10 DG-RY, 10 TG-RY). The 47 early dumping profiles of DG-BI showed immediately sharp rises after a meal, which 47 control profiles did not (P < 0.05). Curves of the 15 late dumping profiles of DG-BI were similar to those of early dumping profiles, with lower glycemic levels. DG-RY and TG-RY late dumping profiles (7 and 13, respectively) showed rapid glycemic decreases from a high glycemic state postprandially to hypoglycemia, with a steeper drop in TG-RY than in DG-RY.

CONCLUSION

Postprandial glycemic changes suggest dumping symptoms after standard gastrectomy for gastric cancer. Furthermore, glycemic profiles during dumping may differ depending on reconstruction methods after gastrectomy.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Favorable Outcomes of Neoadjuvant Chemotherapy and Limited Para-Aortic Lymph Node Dissection for Advanced Gastric Cancer with Para-aortic Lymph Node Metastasis

BACKGROUND

Although para-aortic lymph node (PALN) metastasis from gastric cancer is a non-curative lesion, gastrectomy with complete PALN dissection (PAND) following neoadjuvant chemotherapy (NAC) is a tentative standard treatment in Japan, based on the results of a small-scale phase II clinical trial. However, whether complete PAND (C-PAND) is always necessary for such diseases is open to debate.

METHODS

Patients who received NAC followed by R0 gastrectomy for gastric cancer with clinical PALN metastasis at the Cancer Institute Hospital in Tokyo from 2005 to 2017 were reviewed in the present study. We assessed surgical findings and long-term outcomes.

RESULTS

In total, 44 patients receiving gastrectomy with C-PAND (n = 22) or limited PAND (L-PAND; n = 22) were included. Operation time was significantly longer in the C-PAND than in the L-PAND groups (363 min vs. 271 min, P = 0.037). There was no difference between the two groups in the ypStage classification and pattern of recurrence. The 5-year overall survival (OS) and relapse-free survival (RFS) curves were higher in the L-PAND group than the C-PAND group, without reaching a significant difference. The 5-year OS (42.9% vs. 75.7%, p = 0.017) and RFS (14.3% vs. 48.6%, p = 0.002) were significantly worse in the group of three or more, than in the group of less than three pathological PALN metastasis, whereas increasing numbers of harvested PALN were not associated with improved survival.

CONCLUSIONS

Curative gastrectomy with L-PAND following NAC for gastric cancer involving PALN may be an alternative treatment to C-PAND.

Impact of preoperative chemotherapy as initial treatment for advanced gastric cancer with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) or localized peritoneal metastasis (P1a): a multi-institutional retrospective study

BACKGROUND

Gastric cancer (GC) patients with peritoneal metastasis are defined as stage IV in the Japanese classification of GC. For patients with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) and/or localized peritoneal metastasis (P1a), gastrectomy followed by S1 monotherapy is one of the most widely accepted therapeutic strategy in Japan. This study investigated the efficacy of preoperative chemotherapy as initial treatment in GC patients with CY1 and/or P1a.

METHODS

We retrospectively reviewed GC patients diagnosed with CY1 and/or P1a at 34 institutions in Japan between 2008 and 2012. Selection criteria were: adenocarcinoma, no distant metastasis except CY1 or P1a, and no prior treatment. The subjects were divided into an Initial-Chemotherapy group and an Initial-Surgery group, according to the initial treatment.

RESULTS

A total of 824 patients were collected and 713 eligible patients were identified for this study. As the initial treatment, 150 patients received chemotherapy (Initial-Cx), and 563 patients underwent surgery (Initial-Sx). Initial-Cx regimens were cisplatin plus S1/docetaxel plus cisplatin plus S1/others (n = 90/37/23). Both overall survival (OS) and progression-free survival (PFS) were similar between the Initial-Cx and Initial-Sx groups (median OS 24.8 and 24.0 months, HR 1.07, 95% CI 0.87-1.3; median PFS 14.9 and 13.9 months, HR 1.04, 95% CI 0.85-1.27). The 5-year OS rates were 22.3% in the Initial-Cx group and 21.5% in the Initial-Sx group.

CONCLUSIONS

Although, the preoperative chemotherapy did not show a survival benefit for GC patients with CY1 and/or P1a, initial-Cx showed favorable survival in patients who converted to P0 and CY0.

Different risk factors for three major recurrence patterns of pathological stage II or III gastric cancer patients who completed adjuvant S-1 monotherapy

INTRODUCTION

After curative gastrectomy followed by 1-year adjuvant S-1 monotherapy for pathological stage (pStage) II or III gastric cancer, some patients experience peritoneal, hematogenous, or lymph nodal recurrence. However, risk factors for each recurrence pattern despite completed adjuvant S-1 monotherapy remain unclear. The aim of this study was to determine which factors influence each recurrence type after curative gastrectomy followed by 1-year adjuvant S-1 monotherapy.

MATERIALS AND METHODS

A total of 380 patients with pStage II or III gastric cancer who completed 1-year adjuvant S-1 monotherapy after R0 gastrectomy between January 2008 and December 2013 were enrolled in this study. The risk factors that were associated with peritoneal, hematogenous, and lymph nodal recurrence were investigated by univariate and multivariate analyses.

RESULTS

Eighty (21.1%) of 380 patients developed recurrence. As the first site, peritoneal, hematogenous, and lymph nodal recurrence occurred in 42 (11.1%), 26 (6.8%), and 12 (3.2%) patients, respectively. In multivariate analysis, peritoneal metastasis was associated with signet ring cell carcinoma (P < 0.001), pT4 (P = 0.001), and pN3 (P < 0.001), while hematogenous recurrence was associated with pN3 (P = 0.019) and later initiation of S-1 (P = 0.013), and lymph nodal recurrence was associated with pN3 (P = 0.002).

CONCLUSION

The risk factors for peritoneal, hematogenous, and lymph nodal recurrence in pStage II or III gastric cancer patients who complete adjuvant S-1 monotherapy differ. This information may be helpful for daily surveillance of recurrence in post-operative and chemotherapeutic patients. Furthermore, it may be a useful reference to develop novel perioperative chemotherapy.

Is laparoscopic and endoscopic cooperative surgery (LECS) for gastric subepithelial tumor at the esophagogastric junction safe?

INTRODUCTION

With technique improvements, indications for laparoscopic and endoscopic cooperative surgery (LECS) for gastric subepithelial tumor (SET) are gradually expanding for tumors technically difficult to resect. However, surgical outcomes of LECS, including for esophagogastric junction (EGJ) tumors requiring advanced skills, remain unknown.

METHODS

We reviewed patients in whom LECS had initially been attempted for gastric SET at the Cancer Institute Hospital in Tokyo from June 2006 to May 2018. Indications for LECS at the EGJ have gradually expanded during the study period to include tumors with esophageal invasion up to 2 cm, or less than half the EJG circumference, preoperatively. Surgical outcomes and risk factors for conversion to other procedures were investigated.

RESULTS

Twenty (9.3%) of the 214 total patients had EGJ tumors. Four patients (20%) with EGJ tumors developed postoperative complications (Clavien-Dindo grade ≥ II). Among 12 patients in whom LECS could be completed for EGJ tumors, only one non-serious complication occurred. Eight patients required conversion to another operation for EGJ tumors (two laparotomy, six proximal gastrectomy). Among conversion cases with EGJ tumors, anastomotic leakage occurred in both patients undergoing laparotomy after LECS, necessitating additional defect closure. There was only one non-serious complication in six proximal gastrectomy patients. On multivariate analysis, EGJ tumor was an independent risk factor for conversion to another operation.

CONCLUSION

LECS at the EGJ may be a risk factor for conversion operation, and when performing LECS at the EGJ is difficult, conversion to proximal gastrectomy, which can be performed safely, should be considered.

Oncological Impact of Gross Proximal Margin Length in Distal Gastrectomy for Gastric Cancer: Is the Japanese Recommendation Valid?

Objective

To identify an oncological impact of gross proximal margin (PM) length in distal gastrectomy for cancer.

Summary background data

In Japan, to obtain pathologically negative PMs in gastrectomy for cancer, the Gastric Cancer Treatment Guidelines (GCTGs) recommend maintaining the PM length to at least 2 cm for cT1, 3 cm for the expansive growth type (Exp), and 5 cm for the infiltrative growth type (Inf) of cT2-4. The GCTGs also recommend confirming pathologically negative PMs by intraoperative frozen section analyses when the gross PMs are shorter than the recommendations. However, whether they are valid is unknown.

Methods

Patients who intended to undergo curative distal gastrectomy were included. They were divided into groups A (adherence to the GCTGs) and NA (nonadherence) according to the PM length. The incidence of pathologically positive PMs and survival outcomes were compared between the groups. Propensity scores (PSs) were used in comparisons of survival outcomes to eliminate potential confounders.

Results

A total of 1036 patients were eligible. Pathologically positive PMs were identified in group NA with cT1 and Inf, and the incidence was 1.6% and 3.1%, respectively. Adjusted analysis using the PSs showed comparable survival outcomes between the groups. However, the hazard ratios according to the PSs presented a possible survival advantage in maintaining the recommended gross PM lengths except for cT1 and Exp located in the lower stomach.

Conclusion

Surgeons should maintain the gross PM lengths recommended in the GCTGs to both obtain pathologically negative PMs and avoid survival disadvantages.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ^{-}-^{14}N System

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21  MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

Oncological outcomes in patients with pT1N0-3 or pT2-3N0 gastric cancer after curative resection without adjuvant chemotherapy

PURPOSE

The survival outcomes of pT1N0-3 or pT2-3N0 gastric cancer after curative resection are favorable without adjuvant chemotherapy. However, some patients develop recurrence and details of these recurrences remain unclear. This study aimed to evaluate the prognostic factors in patients with pT1N0-3 or pT2-3N0 gastric cancer.

METHODS

We retrospectively reviewed the medical records of 1219 patients with pT1N0-3 or pT2-3N0 gastric cancer who underwent curative gastrectomy without neoadjuvant or adjuvant chemotherapy between April 2007 and March 2012 at Cancer Institute Hospital.

RESULTS

This cohort included 895 pT1N0, 73 pT1N1, 23 pT1N2, 6 pT1N3, 130 pT2N0, and 92 pT3N0 patients. The 5-year overall survival (OS) and 5-year relapse-free survival (RFS) for pT1N0-3 and pT2-3N0 gastric cancer were 98.9% (95% CI 98.1-99.4) and 97.7% (95% CI 96.7-98.4), respectively. Age (HR 3.56, 95% CI 2.10-6.03) and lymphovascular involvement (hazard ratio (HR) 2.98, 95% CI 1.76-5.04) were independent prognostic factors in a multivariate analysis for RFS. The 5-year RFS for patients aged ≥75 years or with lymphovascular involvement were 94.4% (95% CI 89.8-97.0) and 95.1% (95% CI 92.5-96.8), respectively.

CONCLUSION

The survival outcomes of pT1N0-3 and pT2-3N0 were excellent, even in patients with aged >75 years or lymphovascular involvement which were risk factors. However, the sample size of T1N3 gastric cancer is small, so larger sample size and risk factor analysis are required.

Feasibility study of TAS-118 plus oxaliplatin as perioperative chemotherapy for patients with locally advanced gastric cancer (APOLLO-11)

205

Background:TAS-118 (S-1 and leucovorin) + oxaliplatin (L-OHP) improved overall survival (OS) compared to S-1 + cisplatin for patients (pts) with advanced gastric cancer (GC) (Kang, Lancet Oncol. 2020). This study investigated the feasibility of peri (pre and post)-operative (op) chemotherapy (chemo) with TAS-118 ± L-OHP in pts with locally advanced resectable GC. While it was reported that pre-op TAS-118 + L-OHP followed by D2 gastrectomy was well tolerated and showed promising efficay (Takahari, ASCO-GI. 2020), the recommended post-op chemo regimen, TAS-118 or TAS-118 + L-OHP, has yet to be determined. Methods:Eligible pts with GC of clinical T3-4N1-3M0 were enrolled. The protocol treatment consisted of pre-op chemo with 4 courses of TAS-118 (40-60 mg/body, orally, twice daily, 7 days) + L-OHP (85 mg/m2, intravenously, day 1) in a 2-week cycle, and gastrectomy with D2 lymphadenectomy, followed by post-op chemo with 12 courses of TAS-118 (step 1) and 8 courses of TAS-118 + L-OHP (step 2). Step 2 was started if the dose-limiting toxicity (DLT) occurred in < 6 of 10 pts in step 1. Up to 20 pts were included in the analysis of feasibility after a recommended regimen was determined. Results:Between December 2016 and February 2019, 45 pts were enrolled. The numbers of pts with cT3/4a and cN1/2/3 were 13/32 and 25/17/3, respectively. Excluding 14 pts (4 achieving pathological complete response, 4 not satisfying the criteria for post-op chemo, 3 physician judgement or pt withdrawal, 2 progressive disease, 1 adverse event [AE]), 31 pts (11/20 in step 1/2) received the post-op chemo. No DLT was observed in either step. The post-op chemo completion rate was 90.9% (95% CI, 63.6-99.5) in step 1 and 80.0% (95% CI, 59.9-92.9) in step 2. The median relative dose intensity of TAS-118 in step 1 was 83.3%, and those of TAS-118 and L-OHP in step 2 were 69.9% and 74.3%, respectively. One pt in step 2 discontinued post-op chemo due to AE. Grade ³ 3 AEs observed in ≥ 10% of pts were weight loss in both step 1 and step 2 (2 in each), and hypokalemia (n = 3) and neutropenia (n = 2) in step 2. At 1-year follow-up after the last pt was enrolled, recurrence-free survival and OS rates were 91.1% (95% CI, 78.0-96.6) and 100%, respectively at 12 months, and 69.1% (95% CI, 49.6-82.3) and 95.5% (95% CI, 71.9-99.3), respectively at 24 months. Conclusions:Taken together with the feasibility and efficacy of pre-op chemo, peri-op chemo with TAS-118 + L-OHP with D2 gastrectomy was well tolerated and showed promising efficacy. Clinical trial information: UMIN000024688.

Postprandial Asymptomatic Glycemic Fluctuations after Gastrectomy for Gastric Cancer Using Continuous Glucose Monitoring Device

Purpose

Although dumping symptoms are thought to involve postprandial glycemic changes, postprandial glycemic variability without dumping symptoms remains poorly understood due to the lack of a method that allows the easy and continuous measurement of blood glucose levels.

Materials and Methods

Patients having undergone distal gastrectomy with Billroth-I (DG-BI) or Roux-en-Y reconstruction (DG-RY), total gastrectomy with RY (TG-RY) and pylorus preserving gastrectomy (PPG) for gastric cancer 3 months to 3 years prior, diagnosed as pathological stage I or II, were prospectively enrolled from March 2018 to January 2020. The interstitial tissue glycemic levels were measured every 15 min, up to 14 days by continuous glucose monitoring. Moreover, using a diary recording the diet and symptoms, asymptomatic glucose profiles without sugar supplementation within 3 h postprandially were compared among the four procedures.

Results

A total of 40 patients were enrolled, 10 patients for each of the four procedures. There were 47 glucose profiles with DG-BI, 46 profiles with DG-RY, 38 profiles with TG-RY, and 46 profiles with PPG. PPG showed the slowest increase with a subsequent gradual decrease in glucose fluctuations, without hyperglycemia or hypoglycemia, among the four procedures. In contrast, TG-RY and DG-RY showed spike-like glycemic variability, sharp rises during meals, and rapid drops. The glucose profiles of DG-BI were milder than those of RY.

Conclusions

The asymptomatic glycemic changes after meals differ among the types of surgical procedures for gastric cancer. Given the mild glycemic fluctuations in PPG and the glucose spikes in TG-RY and DG-RY, pylorus preservation and physiological reconstruction without changes in food pathways may optimize postprandial glucose profiles after gastrectomy.

A "Just Enough" Gross Proximal Margin Length Ensuring Pathologically Complete Resection in Distal Gastrectomy for Gastric Cancer

Introduction

The objective of this study is to determine a "just enough" gross proximal margin (PM) length to ensure a pathologically negative PM in distal gastrectomy for gastric cancer. There is a discrepancy between the gross and pathological proximal boundaries of gastric cancer. We must transect the stomach maintaining some safety margins to obtain a pathologically negative PM. However, we have no standard to indicate where to transect the stomach.

Methods

Patients undergoing distal gastrectomy for gastric cancer were enrolled. A new parameter named ΔPM, which corresponded to the pathological extension proximal to the gross tumor boundary toward the resection stump, was evaluated. The number of patients was counted in each ΔPM range of 1-cm increments. The maximum ΔPM was defined as the first value at which the number of patients became 0, and it was determined as the recommended gross PM length for each disease type.

Results

In cT1, 259 and 330 patients were assigned to differentiated (Dif) and undifferentiated types (Und), respectively. The maximum ΔPM was 20 mm for Dif and 40 mm for Und. In cT2-4, 194 and 490 patients were assigned to the expansive (Exp) and infiltrative (Inf) growth types. The maximum ΔPM was 30 mm for Exp. The maximum ΔPM was 50 mm for Inf of less than 80 mm and 60 mm for Inf of 80 mm or more.

Conclusions

A newly recommended gross PM length to ensure pathologically negative PMs in distal gastrectomy for each gastric cancer type was determined.

Clinical outcomes of radical gastrectomy following trastuzumab-based chemotherapy for stage IV HER2-positive gastric or gastroesophageal junction cancer

PURPOSE

Patients who receive trastuzumab (T-mab) plus chemotherapy for stage IV HER2-positive gastric or gastroesophageal junction cancer sometimes respond remarkably well and can undergo radical surgery. However, the clinical outcomes of preoperative T-mab combined chemotherapy with radical gastrectomy remain unclear. We conducted this study to investigate the clinical outcomes of this multimodal treatment.

METHODS

From among a total of 199 patients who received T-mab-based chemotherapy for stage IV HER2-positive gastric or gastroesophageal junction cancer between 2011 and 2018, the subjects of this retrospective analysis were 20 patients who subsequently underwent radical gastrectomy.

RESULTS

Seven patients had gastroesophageal junction cancer and 13 had gastric cancer. Eleven patients had unresectable stage IV cancer and 9 had resectable metastatic disease. Chemotherapy regimens included capecitabine, cisplatin + T-mab (11 patients), and S-1, oxaliplatin + T-mab (nine patients). The median number of chemotherapy cycles before surgery was three (range, 2-62). During preoperative chemotherapy, grade 3/4 adverse events developed in six patients. None suffered grade ≥ 3b postoperative complications. The 3-year relapse-free survival (RFS) and overall survival (OS) rates were 58.9% and 89.5%, respectively.

CONCLUSION

Combined preoperative T-mab-based chemotherapy and surgery appears to be safe and effective for stage IV HER2-positive gastric or gastroesophageal junction cancer, with a clinically meaningful impact on RFS and OS.

Perirenal fat thickness as a predictor of postoperative complications after laparoscopic distal gastrectomy for gastric cancer

Background

Laparoscopic distal gastrectomy is used widely in surgery for gastric cancer. Excess visceral fat can limit the ability to dissect the suprapancreatic region, potentially increasing the risk of local complications, particularly pancreatic fistula. This study evaluated perirenal fat thickness as a surrogate for visceral fat to see whether this was related to complications after laparoscopic distal gastrectomy.

Methods

Perirenal fat thickness was measured dorsal to the left kidney as an indicator of visceral fat in patients with gastric cancer who underwent laparoscopic distal gastrectomy. Patients were divided into two groups: those with and those without complications. The relationship between perirenal fat thickness and postoperative complications was evaluated.

Results

The optimal cut‐off value for predicting morbidity using adipose tissue thickness was 10·7 mm; a distance equal to or greater than this was considered a positive perirenal fat thickness sign (PTS). A positive PTS showed a significant correlation with visceral fat area. Multivariable analysis found that a positive PTS was an independent risk factor for complications (hazard ratio 4·42, 95 per cent c.i. 2·31 to 8·86; P < 0·001).

Conclusion

Perirenal fat thickness as an indicator of visceral fat was an independent predictor of postoperative complications after laparoscopic distal gastrectomy for gastric cancer.

Pancreatic atrophy after gastrectomy for gastric cancer

PURPOSE

To investigate the phenomenon of pancreatic atrophy after gastrectomy for gastric cancer, using computed tomography (CT) volumetry.

METHODS

The subjects of this retrospective study were 77 patients who underwent distal gastrectomy (DG) or total gastrectomy (TG) for pStage I gastric cancer in 2014. The relative pancreatic volume ratio was assessed preoperatively, and then 1 and 5 years postoperatively and the results were compared between surgical procedures RESULTS: A total of 14 patients underwent TG with Roux-en-Y (RY) reconstruction, 24 underwent DG with Billroth-I (BI) reconstruction, and 39 underwent DG with RY reconstruction. We observed that the pancreatic volume continued to decrease over the 5 years after DG or TG. Furthermore, the incidence of pancreatic atrophy 5 years postoperatively was significantly greater after TG than after DG. In patients who underwent DG, a greater incidence of pancreatic atrophy was observed after RY reconstruction than after BI reconstruction, 5 years postoperatively.

CONCLUSION

The pancreatic volume continued to decrease after DG and TG for gastric cancer 5 years after treatment. TG was associated with a significantly greater incidence of pancreatic atrophy than DG 5 years postoperatively, as was RY reconstruction vs. BI reconstruction after DG.

Therapeutic value of splenectomy to dissect splenic hilar lymph nodes for type 4 gastric cancer involving the greater curvature, compared with other types

BACKGROUND

Whether splenectomy for splenic hilar lymph node (No. 10) dissection in type 4 gastric cancer involving the greater curvature is necessary is not established. Patients with type 4 gastric cancer often experience peritoneal relapse, despite curative surgery, and total gastrectomy with splenectomy is frequently associated with infectious complications.

METHOD

Patients with cT2-T4 gastric cancer in the upper or middle third of the stomach, or both, involving the greater curvature who underwent R0 total gastrectomy with splenectomy between 2006 and 2016 were selected. Clinicopathological findings, postoperative complications, the incidence of lymph node metastasis, and the therapeutic value index of each station were compared between type 4 and non-type 4 gastric cancer.

RESULTS

We enrolled 50 patients with type 4 and 60 with non-type 4. The former had a significantly higher proportion of the undifferentiated type and larger and deeper tumors. The overall incidence of Grade III or higher complications was 20.9%. The incidence of No. 10 metastasis was 26.0% in type 4 and 31.7% in non-type 4. Although the therapeutic value index of the No. 10 was 13.7 in type 4 and 15.0 in non-type 4, the index of type 4 ranked just below several peri-gastric stations and seventh, while that in non-type 4 ranked second.

CONCLUSION

Splenectomy for No. 10 dissection may be oncologically valid for type 4 gastric cancer involving the greater curvature. A safer procedure for No. 10 dissection should be established.