Feasibility of weekly intraperitoneal versus intravenous paclitaxel therapy delivered from the day of radical surgery for gastric cancer: a preliminary safety analysis of the INPACT study, a randomized controlled trial

The Genomic Signatures of Linitis Plastica Signal the Entrance into a New Era: Novel Approaches for Diagnosis and Treatment

Linitis Plastica (LP) is a rare and aggressive tumor with a distinctive development pattern, leading to the infiltration of the gastric wall, the thickening of the gastric folds and a "leather bottle appearance". LP is an extremely heterogeneous tumor caused by mutations in oncogenic and tumor suppressive genes, as well as molecular pathways, along with mutations in stromal cells and proteins related to tight junctions. Elucidating the molecular background of tumorigenesis and clarifying the correlation between cancerous cells and stromal cells are crucial steps toward discovering novel diagnostic methods, biomarkers and therapeutic targets/agents. Surgery plays a pivotal role in LP management, serving both as a palliative and curative procedure. In this comprehensive review, we aim to present all recent data on the molecular background of LP and the novel approaches to its management.

Sustained co-delivery of 5-fluorouracil and cis-platinum via biodegradable thermo-sensitive hydrogel for intraoperative synergistic combination chemotherapy of gastric cancer

Gastric cancer is the fifth most common cancer and the third leading cause of cancer death worldwide, posing a severe threat to human health. Surgical resection remains the most preferred option for gastric cancer treatment. However, for advanced gastric cancer, the curative effect of surgical resection is usually limited by the local recurrence, peritoneal carcinomatosis, or distal metastasis. Intraoperative chemotherapy is an attractive in situ adjuvant treatment strategy to reduce the recurrence and metastasis after surgical resection. Here, we designed a 5-fluorouracil (5-FU) and cis-platinum (DDP) co-delivery system based on a biodegradable temperature-sensitive hydrogel (PDLLA-PEG-PDLLA, PLEL) for intraoperative adjuvant combination chemotherapy of gastric cancer. This 5-FU + DDP/PLEL hydrogel system characterized by a special sol-gel phase transition in response to physiological temperature and presented sustained drug release in vitro and in vivo. A strong synergistic cell proliferation inhibition and apoptosis promotion of 5-FU + DDP/PLEL were observed against gastric cancer MKN45-luc cells. After intraperitoneal injection, the dual-drug loaded hydrogel formulation showed superior anti-tumor effects than the single-drug carrying hydrogels and combination of free 5-FU and DDP on the gastric cancer peritoneal carcinomatosis model. The use of hydrogel for dual-drug delivery had benefited to fewer side effects as well. What's more, we established a mouse model for postsurgical residual tumors and peritoneal carcinomatosis of gastric cancer, in which the intraoperative administration of 5-FU + DDP/PLEL also remarkably inhibited the local recurrence of the orthotopic tumors and the growth of the abdominal metastatic tumors, resulting in an extended lifetime. Hence, this developed dual-drug loaded hydrogel system has great potential in the intraoperative chemotherapy of gastric cancer, that suggests a clinically-relevant and valuable option for postsurgical management of gastric cancer.

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Intraoperative chemotherapy could reduce the recurrence and metastasis after surgical resection of gastroenteric tumors.

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5-FU and DDP co-delivery system based on PLEL was developed for intraoperative combination chemotherapy of gastric cancer.

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This dual-drug loaded hydrogel helped to improve synergistic anti-tumor effects and reduce adverse side effects in vivo.

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5-FU+DDP/PLEL could inhibit recurrence of orthotopic tumors and growth of abdominal metastatic tumors in gastric cancer.

Clinical significance of initial treatment for peritoneal lavage cytology-positive gastric cancer: outcomes according to treatment strategy

Background

Although patients with positive lavage cytology (CY1) are classified as having stage IV disease, long-term survival without other unresectable factors (P0CY1) has been reported. Conversion gastrectomy in patients with a change in cytology status after induction chemotherapy might improve survival, but appropriate treatment remains controversial. Here, we reviewed our experience in treating CY1 gastric cancer to evaluate the best treatment strategy.

Methods

Clinical and pathological findings of patients with a diagnosis of P0CY1 gastric cancer at Toranomon Hospital between February 2006 and April 2019 were retrospectively analyzed. Patients were classified into two groups according to initial treatment: a surgery-first group and a chemotherapy-first group. In addition, the patients were categorized into subgroups based on the subsequent treatment pattern. The surgery-first group was divided into two subgroups: adjuvant chemotherapy and palliative gastrectomy only. The chemotherapy-first group was divided into three subgroups with the subsequent treatment pattern depending on the response to chemotherapy: conversion gastrectomy, palliative gastrectomy after induction therapy, and palliative chemotherapy.

Results

In total, 38 patients were eligible for inclusion in this study. After initial assessment of cytology status, 21 patients underwent gastrectomy as initial treatment (surgery first) and 17 received induction chemotherapy (chemotherapy first). Ten patients underwent surgery first with adjuvant chemotherapy, 11 underwent palliative gastrectomy alone, 5 underwent conversion surgery, 5 with CY1 disease after induction chemotherapy underwent palliative gastrectomy, and 7 received palliative chemotherapy only. The 3-year survival rate was 23.4% (median survival, 17.7 months) in the surgery-first group and 27.3% (median survival, 19.7 months) in the chemotherapy-first group. The 3-year survival rate was 75% for conversion gastrectomy, 16.7% for palliative chemotherapy, and 0% for palliative gastrectomy after induction chemotherapy.

Conclusions

There was no significant difference in outcome according to whether surgery or chemotherapy was performed first. The prognosis of conversion surgery with curative resection was better than that of the other types of treatment. However, the outlook after induction chemotherapy was poor. Patients with advanced gastric cancer should be treated cautiously until more effective treatment options become available.

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.

The type of gastrectomy affects skeletal muscle loss and the long-term outcomes of elderly patients with gastric cancer: a retrospective study using computed tomography images

PURPOSE

Sarcopenia is common in elderly gastrectomized patients and a known risk factor for postoperative complications and poor overall survival. However, the long-term outcomes of skeletal muscle loss after gastrectomy and the differences in outcomes of different gastrectomy procedures remain unclear.

METHODS

The subjects of this retrospective study were 136 patients who underwent various gastrectomy procedures for early gastric cancer, namely: total gastrectomy (TG; n = 20), proximal gastrectomy (PG; n = 16), distal gastrectomy (DG; n = 60), and pylorus-preserving gastrectomy (PPG; n = 40). Skeletal muscle volume (SMV), calculated as the skeletal muscle index (SMI), was measured using cross-sectional computed tomography (CT) scans preoperatively and then 1, 2, and 3 years after gastrectomy.

RESULTS

Sarcopenia developed from 2 years onwards in all the patients who underwent TG. The SMI and sarcopenia prevalence after gastrectomy deteriorated over time. Multivariate analysis revealed that TG and PG were significant risk factors for skeletal muscle loss in postoperative years 1 and 3. A decrease in the SMI after TG or PG was most remarkable in elderly patients.

CONCLUSIONS

The type of gastrectomy affects skeletal muscle loss in the long term. Elderly patients who undergo TG or PG are at high risk of severe skeletal muscle loss.

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.

TNFAIP6 promotes invasion and metastasis of gastric cancer and indicates poor prognosis of patients

TNFα-stimulated gene-6 (TNFAIP6) plays an important role in the prognosis of many tumors. Our objective was to investigate the clinical and prognostic value of TNFAIP6 expression in gastric cancer (GC) patients. Here, we investigated the expression of TNFAIP6 in GC tissues using western blotting and immunohistochemistry and the association between TNFAIP6 expression and the prognosis and clinicopathological parameters of GC patients. Our results revealed that the expression of TNFAIP6 was higher in GC tissue than in normal gastric tissue, and the levels were positively correlated with the depth of tumor invasion (P = 0.010), tumors with lymph node metastasis (P = 0.000) and TNM stage (P = 0.003) of GC patients. Moreover, the results revealed that patients with high TNFAIP6 expression exhibited poorer overall survival than those with low TNFAIP6 expression (P = 0.037). Additionally, knockdown of TNFAIP6 inhibited the proliferation, invasion and metastasis of GC cells in vitro. High TNFAIP6 expression was associated with the depth of tumor invasion, lymph node metastasis, TNM stage and poor prognosis of GC patients, suggesting that TNFAIP6 may serve as a novel indicator of the prognosis and as a treatment target of GC.

Development and validation of a novel staging system integrating the number and location of lymph nodes for gastric adenocarcinoma

Background

Evidence suggests that the anatomic extent of metastatic lymph nodes (MLNs) affects prognosis, as proposed by alternative staging systems. The aim of this study was to establish a new staging system based on the number of perigastric (PMLN) and extra-perigastric (EMLN) MLNs.

Methods

Data from a Chinese cohort of 1090 patients who had undergone curative gastrectomy with D2 or D2 plus lymphadenectomy for gastric cancer were retrospectively analysed. A Japanese validation cohort (n = 826) was included. Based on the Cox proportional hazards model, the regression coefficients of PMLN and EMLN were used to calculate modified MLN (MMLN). Prognostic performance of the staging systems was evaluated.

Results

PMLN and EMLN were independent prognostic factors in multivariate analysis (coefficients: 0.044, 0.115; all P < 0.001). MMLN was calculated as follows: MMLN = PMLN + 2.6 × EMLN. The MMLN staging system showed superior prognostic performance (C-index: 0.751 in the Chinese cohort; 0.748 in the Japanese cohort) compared with the five published LN staging systems when MMLN numbers were grouped as follows: MMLN0 (0), MMLN1 (1–4), MMLN2 (5–8), MMLN3 (9–20), and MMLN4 (>20).

Discussion

The MMLN staging system is suitable for assessing overall survival among patients undergoing curative gastrectomy with D2 or D2 plus lymphadenectomy.

Operative and Oncological Outcomes After D2 Versus D1 Gastrectomy of Operable Gastric Cancer: an Observational Study

BACKGROUND

The optimal surgery for operable gastric carcinoma is still controversial. The aim of the current study was to assess the outcomes of D2 compared with D1 gastrectomy.

STUDY

This observational study included 80 patients with operable gastric cancer treated by D2 gastrectomy at Alexandria University Hospital between January 2010 and January 2016. Another 68 patients treated by D1 gastrectomy during the same period were included. Both groups were compared regarding operative mortality, morbidities, tumor recurrence, and 5-year survival rates.

RESULTS

D2 gastrectomy had a significantly higher postoperative mortality and morbidity rates compared with D1 group (19.4% and 41.9% versus 6.3% and 18.8%). Mean number of LNs retrieved was statistically increased in D2 compared with D1 group with more frequency of adequate lymphadenectomy (LN retrieved > 15). D2 gastrectomy demonstrated significant lower recurrence and cancer-specific mortality rates compared with D1 group (18.6% and 14.5% versus 34.9% and 30.8%) with no significant difference in DFS and OS rates. Spleen-saving D2 gastrectomy showed no significant difference in early postoperative mortality with significant increase in DFS and OS compared with D1 gastrectomy (78.7% and 82% versus 61.5% and 64.6%).

CONCLUSIONS

D2 gastrectomy had a lower recurrence and cancer-specific mortality rates than D1 gastrectomy but it had higher postoperative mortality and morbidity rates that resulted in no overall survival benefit of D2 compared with D1 gastrectomy. Spleen-saving D2 gastrectomy can be done safely in selected patients by expert surgeons without increased morbidity and mortality and better survival outcomes.

Endoscopic Submucosal Dissection for Upper Gastrointestinal Neoplasia-a North American Perspective

OBJECTIVES

Organ-sparing endoscopic submucosal dissection (ESD) is an acceptable treatment strategy for superficial neoplastic lesions of the esophagus and stomach. The adoption of this technique has lagged in North America compared with Asia, and we sought to report on our experiences with ESD for upper GI neoplasia.

METHODS

A prospectively entered database of all patients undergoing endoscopic resection of esophageal and gastric neoplasia at McGill University from 2009 to 2019 was queried for those who received ESD.

RESULTS

A total of 103 consecutive ESDs were identified from 2009 to 2019. Seventy-one (69%) patients were male and the median age was 72 (range: 38-90). Sixty-one (59%) cases were esophageal and 42 (41%) gastric. Forty-nine (48%) were performed in the endoscopy suite under local sedation only. Perforation occurred in 9 patients (7 esophageal and 2 stomach), of which 3 required operative repair. Histology was principally invasive carcinoma (79, 77%), with 17 (16%) dysplastic lesions (e.g., HGD), 1 (1%) neuroendocrine tumor, and 7 (7%) benign lesions. En bloc resection was achieved in 90 (87%), and the complete resection rate was 74 (72%), with 51 (50%) of procedures fulfilling the criteria for curative resection. At medium of 23-month (2-199) follow-up of these 51 curative resections, one case of recurrent carcinoma was found at follow-up and was managed with repeat endoscopic resection. Non-curative ESDs were found 45 (R1 resection = 29: risk of lymph node metastasis = 16), 21 had active surveillance, and 24 were resected.

CONCLUSION

ESD is a viable, effective, and safe therapeutic and staging modality for superficial lesions of the stomach and esophagus.

Proximal Anterior-Antrum Posterior (PAAP) Overlapping Anastomosis in Minimally Invasive Pylorus-Preserving Gastrectomy for Early Gastric Cancer Located in the High Body and Posterior Wall of the Stomach

Purpose

To evaluate the feasibility and safety of intracorporeal overlapping gastrogastrostomy between the proximal anterior wall and antrum posterior wall (PAAP; PAAP anastomosis) of the stomach in minimally invasive pylorus-preserving gastrectomy (PPG) for early gastric cancer (EGC).

Materials and Methods

From December 2016 to December 2019, 17 patients underwent minimally invasive PPG with PAAP anastomosis for EGC in the high body and posterior wall of the stomach. Intraoperative gastroscopy was performed with the rotation maneuver during proximal transection. A longer antral cuff (>4-5 cm) was created for PAAP than for conventional PPG (≤3 cm) at the point where a safe distal margin and good vascular perfusion were secured. Because the posterior wall of the proximal remnant stomach was insufficient for intracorporeal anastomosis, the anterior wall was used to create an overlapping anastomosis with the posterior wall of the remnant antrum. The surgical and oncological outcomes were analyzed, and the stomach volume was measured in patients who completed the 6-month follow-up. The results were compared to those after conventional PPG (n=11 each).

Results

PAAP anastomosis was successfully performed in 17 patients. The proximal and distal resection margins were 2.4±1.9 cm and 4.0±2.6 cm, respectively. No postoperative complications were observed during the 1-year follow-up esophagogastroduodenoscopy (n=10). The postoperative remnant stomach (n=11) was significantly larger with PAAP than with conventional PPG (225.6±118.3 vs. 99.1±63.2 mL; P=0.001). The stomach length from the anastomosis to the pylorus was 4.9±2.4 cm after PAAP.

Conclusions

PAAP anastomosis is a feasible alternative for intracorporeal anastomosis in minimally invasive PPG for highly posteriorly located EGC.

Subcutaneous fat area as a risk factor for extraction site incisional hernia following gastrectomy for gastric cancer

PURPOSE

To identify the incidence of extraction site incisional hernia following gastrectomy for gastric cancer and its significant risk factors, including the subcutaneous fat area.

METHODS

We reviewed data gathered prospectively on patients with gastric cancer, who underwent gastrectomy between 2008 and 2012 at Kyushu University Hospital, Fukuoka, Japan. The subcutaneous fat area (SFA) and visceral fat area (VFA) were measured using axial computed tomography at the level of the L4 and L3 transverse processes, and the L2-L3 intervertebral disc. The primary endpoint of the rate of extraction site incisional hernia was based on the computed tomography and clinical data including hospital follow-up reports.

RESULTS

After applying the inclusion and exclusion criteria, 320 patients were included in this retrospective analysis: 3.1% (10/320) had extraction site incisional hernias after a mean follow-up of 11 months. Multivariate analysis revealed that age and the SFA were independent risk factors (age ≥ 70.5 years: P = .013, odds ratio: 9.116, 95% confidence interval 1.581-52.553; L4 SFA ≥ 124 cm²: P = .004, odds ratio: 13.752, 95% confidence interval 2.290-82.582).

CONCLUSION

Age and the SFA were independent risk factors for extraction site incisional hernia in patients undergoing gastrectomy for gastric cancer.

Analysis of lymph node metastasis in early gastric cancer: a single institutional experience from China

BACKGROUND

Lymph node metastasis (LNM) has a strong influence on the prognosis of patients with early gastric cancer (EGC). The aim of this study was to reveal the incidence of LNM and evaluate risk factors for LNM to determine the appropriate treatment for EGC in a Chinese population.

METHODS

Patients who underwent radical gastrectomy with lymph node dissection for EGC between 2012 and 2017 were retrospectively analyzed. Univariate and multivariate analyses were conducted to identify clinicopathological features that were risk factors for LNM.

RESULTS

A total of 1033 patients with EGC were enrolled. Of these patients, 668 (64.7%) were men, and 365 (35.3%) were women, ranging in age from 19 to 82 years (mean 56.9 ± 10.9 years). LNM was detected in 173(16.7%) patients with EGC. Among 508 patients with mucosal cancer, 44 (8.7%) patients had LNM. In 525 patients with submucosal cancer, the incidence of LNM was 24.6% (129/525). The age, gender, tumor size, type of differentiation, Lauren classification, and lymphovascular and perineural invasion showed a significant correlation with the rate of LNM in EGC by univariate and multivariate analyses. Patients with submucosal gastric cancer had an older age, a higher proportion of proximal lesion, larger tumor size, more frequent lymphovascular invasion, perineural invasion, and more LNM than patients with mucosal gastric cancer.

CONCLUSIONS

Our study revealed a relatively high incidence of LNM in EGC, compared with Japanese and Korean cohorts. Female sex, large tumor size, undifferentiated-type, and lymphovascular invasion were independent risk factors for LNM in EGC. Radical gastrectomy with lymphadenectomy should be performed in EGC patients with a high risk of LNM.

Laparoscopic gastrectomy with D2 lymphadenectomy for gastric cancer: initial Egyptian experience at the National Cancer Institute

BACKGROUND

Laparoscopic gastrectomy has been used as a superior alternative to open gastrectomy for the treatment of early gastric cancer. However, the application of laparoscopic D2 lymphadenectomy remains controversial. This study aimed to evaluate the feasibility and outcomes of laparoscopic gastrectomy with D2 lymphadenectomy for gastric cancer.

RESULTS

Between May 2016 and May 2018, twenty-five consecutive patients with gastric cancer underwent laparoscopic D2 gastrectomy: eighteen patients (72%) underwent distal gastrectomy, four patients (16%) underwent total gastrectomy, and three patients (12%) underwent proximal gastrectomy. The median number of lymph nodes retrieved was 18 (5-35). A positive proximal margin was detected in 2 patients (8%). The median operative time and amount of blood loss were 240 min (200-330) and 250 ml (200-450), respectively. Conversion to an open procedure was performed in seven patients (28%). The median hospital stay period was 8 days (6-30), and the median time to start oral fluids was 4 days (3-30). Postoperative complications were detected in 4 patients (16%). There were two cases of mortality (8%) in the postoperative period, and two patients required reoperation (8%).

CONCLUSIONS

Laparoscopic gastrectomy with D2 lymphadenectomy can be carried out safely and in accordance with oncologic principles.

Increased assessment of HER2 in metastatic gastroesophageal cancer patients: a nationwide population-based cohort study

BACKGROUND

Addition of trastuzumab to first-line palliative chemotherapy in gastroesophageal cancer patients with HER2 overexpression has shown to improve survival. Real-world data on HER2 assessment and administration of trastuzumab are lacking. The aim of this study was to assess HER2 testing, trastuzumab administration, and overall survival (OS) in a nationwide cohort of metastatic gastroesophageal cancer patients.

METHODS

Data of patients with synchronous metastatic gastroesophageal adenocarcinoma diagnosed in 2010-2016 that received palliative systemic treatment (n = 2846) were collected from the Netherlands Cancer Registry and Dutch Pathology Registry. The ToGA trial criteria were used to determine HER2 overexpression. Proportions of HER2 tested patients were analyzed between hospital volume categories using Chi-square tests, and over time using trend analysis. OS was tested using the Kaplan Meier method with log rank test.

RESULTS

HER2 assessment increased annually, from 18% in 2010 to 88% in 2016 (P < 0.01). Median OS increased from 6.9 (2010-2013) to 7.9 months (2014-2016; P < 0.05). Between the hospitals, the proportion of tested patients varied between 29-100%, and was higher in high-volume hospitals (P < 0.01). Overall, 77% of the HER2 positive patients received trastuzumab. Median OS was higher in patients with positive (8.8 months) and negative (7.4 months) HER2 status, compared to non-tested patients (5.6 months; P < 0.05).

CONCLUSION

Increased determination of HER2 and administration of trastuzumab have changed daily practice management of metastatic gastroesophageal cancer patients receiving palliative systemic therapy, and possibly contributed to their improved survival. Further increase in awareness of HER2 testing and trastuzumab administration may improve quality of care and patient outcomes.

[Importance of splenectomy in the operative treatment of gastric cancer]

BACKGROUND

The value of simultaneous splenectomy as part of an oncologically adequate resection for gastric cancer has been controversially discussed over the last decades.

METHODS

As part of a prospective multicenter observational study data were obtained from patients admitted to hospital with histologically diagnosed primary gastric cancer or adenocarcinoma of the esophagogastric junction (AEG). The profiles of care of patients who had undergone surgical treatment in 141 surgical departments from 1 January 2007 to 31 December 2009 were collated. Overall, 2897 patients were enrolled in the study (tumor resection, n = 2545).

RESULTS

The overall splenectomy rate was 11.1% (n = 283) and the highest proportion was found in AEG tumor lesions (19.4%). In the whole group of patients as well as depending on the tumor site, there was a higher preoperative comorbidity in splenectomized patients. While the rate of general postoperative complications after splenectomy was significantly increased in all patients and also depending on various tumor sites, there were no differences in the rate of specific postoperative complications. A significantly higher hospital mortality comparing the splenectomy group of patients with those in whom the spleen could be preserved, was only observed in AEG-associated tumor lesions (15.2% vs. 5.0%). All splenectomized patients showed a shorter long-term survival (p < 0.001) compared to resections with a preserved spleen (18 months vs. 36 months).

CONCLUSION

In the surgical treatment of gastric cancer, splenectomy can be considered a negative predictor for a worse perioperative outcome and a worse long-term survival.

Intramucosal-lymphatic invasion has a slight impact on lymph node metastasis in patients with early gastric cancer

PURPOSE

Lymphatic invasion (LI) is associated with lymph node metastasis (LNM) and a poor prognosis in patients with early gastric cancer (EGC). Although the impact of the LI volume on LNM has been described, no reports have assessed the impact of its depth on LNM.

METHODS

A total of 360 EGC patients with pathologically proven LI who underwent radical gastrectomy with lymphadenectomy between January 2005 and June 2018 at our institution were extracted from our database. Patients were divided into 2 groups: the mLI group, in which LI was limited to the muscularis mucosae (n = 34); and the smLI group, in which LI reached the submucosal region (n = 326). Clinicopathological features, including the LNM incidence, were compared between the groups.

RESULTS

LNM was recognized in 3 patients (9%) in the mLI group and 101 (31%) in the smLI group (P = 0.005). In the mLI group, LNM was not recorded in any patients who met the curative criteria of ESD other than mLI.

CONCLUSIONS

LI limited to the mucosal region does not seem to be a strong indicator for LNM. When pathological findings of an endoscopic submucosal dissection specimen show only mLI as a non-curative criterion, the probability of LNM may be very low.

Genomewide Expression Profiling Identifies a Novel miRNA-Based Signature for the Detection of Peritoneal Metastasis in Patients With Gastric Cancer

OBJECTIVE

This study aimed to conduct a genomewide transcriptomic profiling to develop a microRNA (miRNA)-based signature for the identification of peritoneal metastasis (PM) in patients with gastric cancer (GC).

SUMMARY BACKGROUND DATA

Even though PM in patients with GC has long been recognized to associate with poor prognosis, currently there is lack of availability of molecular biomarkers for its robust diagnosis.

METHODS

We performed a systematic biomarker discovery by analyzing miRNA expression profiles in primary tumors from GC patients with and without PM, and subsequently validated the expression of candidate miRNA biomarkers in 3 independent clinical cohorts of 354 patients with advanced GC.

RESULTS

Five miRNAs (miR-30a-5p, -134-5p, -337-3p, -659-3p, and -3917) were identified during the initial discovery phase; three of which (miR-30a-5p, -659-3p, and -3917) were significantly overexpressed in the primary tumors from PM-positive patients in the testing cohort (P = 0.002, 0.04, and 0.007, respectively), and distinguished patients with versus without peritoneal metastasis with the value of area under the curve (AUC) of 0.82. Furthermore, high expression of these miRNAs also associated with poor prognosis (hazard ratio = 2.18, P = 0.04). The efficacy of the combination miRNA signature was subsequently validated in an independent validation cohort (AUC = 0.74). Finally, our miRNA signature when combined together with the macroscopic Borrmann's type score offered a much superior diagnostic in all 3 cohorts (AUC = 0.87, 0.76, and 0.79, respectively).

CONCLUSIONS

We have established an miRNA-based signature that have a potential to identify peritoneal metastasis in GC patients.

Long-term Survival Outcomes of Laparoscopic Gastrectomy for Advanced Gastric Cancer: Five-year Results of a Phase II Prospective Clinical Trial

Purpose

Despite an increased acceptance of laparoscopic gastrectomy (LG) in early gastric cancer (EGC), there is insufficient evidence for its oncological safety in advanced gastric cancer (AGC). This is a prospective phase II clinical trial to evaluate the feasibility of LG with D2 lymph node dissection (LND) in AGC.

Materials and Methods

The primary endpoint was set as 3-year disease-free survival (DFS). The eligibility criteria were as follows: 20-80 years of age, cT2N0-cT4aN3, American Society of Anesthesiologists score of 3 or less, and no other malignancy. Patients were enrolled in this single-arm study between November 2008 and May 2012. Exclusion criteria included cT4b or M1, or having final pathologic results as EGC. All patients underwent D2 lymphadenectomy. Three-year DFS rates were estimated by the Kaplan-Meier method.

Results

A total of 157 patients were enrolled. The overall local complication rate was 10.2%. Conversion to open surgery occurred in 11 patients (7.0%). The mean follow-up period was 55.0±20.4 months (1–81 months). The cumulative 3-year DFS rates were 76.3% for all stages, and 100%, 89.3%, 100%, 88.0%, 71.4%, and 35.3% for stage IB, IIA, IIB, IIIA, IIIB, and IIIC, respectively. Recurrence was observed in 37 patients (23.6%), including hematogenous (n=6), peritoneal (n=13), locoregional (n=1), distant node (n=8), and mixed recurrence (n=9).

Conclusions

In addition to being technically feasible for treatment of AGC in terms of morbidity, LG with D2 LND for locally advanced gastric cancer showed acceptable 3-year DFS outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT01441336

Risk factors for lymph node metastasis in non-sentinel node basins in early gastric cancer: sentinel node concept

BACKGROUND

Sentinel node (SN) concept is being applied to early gastric cancer. However, when SNs are positive for metastasis, it is unclear how often LNs in other LN basins show metastasis. We aimed to investigate LN metastasis possibility in LN basins without SNs (non-SN basins). We determined risk factors for metastasis in non-SN basins and identified a prediction model for non-SN basin metastasis using classification and regression tree (CART) analysis.

METHODS

We enrolled 550 patients who were diagnosed with cT1N0M0 or cT2N0M0 gastric cancer with a single lesion and underwent SN mapping. We adopted a dual-tracer method using a radioactive colloid and blue dye to detect SNs.

RESULTS

Of all, 45 (8.2%) patients had SN metastasis; we divided them into two groups: LN metastasis positive and LN metastasis negative in non-SN basins. Univariate analysis showed that the groups differed significantly regarding lymphatic invasion (p = 0.007), number of identified SNs (p = 0.032), and macrometastasis in SN basins (p = 0.005). The CART decision tree for predicting LN metastasis in non-SN basins had area under the curve value of 0.86. Moreover, there were significantly differences in cancer-specific survival (CSS) between the two groups (p = 0.028).

CONCLUSIONS

Macrometastasis in SN basins, lymphatic invasion, and number of identified SNs ≥ 5 are risk factors for LN metastasis in non-SN basins among gastric cancer patients. We identified a prediction model with CART analysis; patients with macrometastasis in SN basins and lymphatic invasion were considered to be at the highest risk for LN metastasis.

A randomized phase II multicenter trial to explore efficacy of weekly intraperitoneal in comparison with intravenous paclitaxel administered immediately after gastrectomy to the patients with high risk of peritoneal recurrence: final results of the INPACT trial

BACKGROUND

Intraperitoneal administration of paclitaxel had been considered a promising option to treat peritoneal metastasis, the most frequent pattern of recurrence in gastric cancer after D2 gastrectomy, but its safety and efficacy after gastrectomy had not been fully explored.

METHODS

A phase II randomized comparison of postoperative intraperitoneal (IP) vs. intravenous (IV) paclitaxel was conducted. Patients with resectable gastric linitis plastica, cancer with minimal amount of peritoneal deposits (P1), or cancer positive for the peritoneal washing cytology (CY1) were eligible. After intraoperative confirmation of the above disease status and of resectability, patients were randomized to be treated either by the IP therapy (paclitaxel 60 mg/m² delivered intraperitoneally on days 0, 14, 21, 28, 42, 49, and 56) or the IV therapy (80 mg/m² administered intravenously using the identical schedule) before receiving further treatments with evidence-based systemic chemotherapy. The primary endpoint was 2-year survival rate.

RESULTS

Of the 86 patients who were randomized intraoperatively, 83 who actually started the protocol treatment were eligible for analysis (n = 39, IP group; n = 44, IV group). The 2-year survival rate of the IP and IV groups was 64.1% (95% CI 47.9-76.9) and 72.3% (95% CI 56.3-83.2%), respectively (p = 0.5731). The IP treatment did not confer significant overall or progression-free survival benefits, and was associated with particularly poor performance in patients with residual disease, including the CY1 P0 population.

CONCLUSIONS

We were unable to prove superiority of the IP paclitaxel over IV paclitaxel delivered after surgery to control advanced gastric cancer with high risk of peritoneal recurrence.

Surgery with curative intent for stage IV gastric cancer: Is it a reality of illusion?

Gastric cancer with metastases outside of the regional lymph nodes is deemed oncologically unresectable. Nevertheless, some metastatic lesions are technically resectable by applying established surgical techniques such as para-aortic lymphadenectomy and hepatectomy. At the time of compilation of the Japanese gastric cancer treatment guidelines version 4, systematic reviews were conducted to see whether it is feasible to make any recommendation to dissect both the primary and metastatic lesions with intent to cure, possibly as part of multimodality treatment. Long-term survivors were found among carefully selected groups of patients both in prospective and retrospective studies. In addition, there is a growing list of publications reporting encouraging outcomes of gastrectomy conducted after exceptionally good response to chemotherapy, usually among patients who underwent R0 resection. This type of surgery is often referred to as conversion surgery. It is sometimes difficult to define a clear borderline between curative surgery scheduled after neoadjuvant chemotherapy and the conversion surgery. This review summarizes what we knew after the literature reviews conducted at the time of compiling the Japanese guidelines and in addition reflects some new findings obtained thereafter through clinical trials and retrospective studies. Metastases were divided into three categories based on the major metastatic pathways: lymphatic, hematogenous, and peritoneal. In each of these categories, there were findings that could provide hope for patients with metastatic disease. These findings implied that the surgical technique that we already use could become more useful upon further developments in antineoplastic agents and drug delivery.

Recent advances in the management of gastric adenocarcinoma patients

Gastric adenocarcinoma (GAC) is one of the most aggressive malignancies and has a dismal prognosis. Therefore, multimodality therapies to include surgery, chemotherapy, targeted therapy, immunotherapy, and radiation therapy are needed to provide advantage. For locally advanced GAC (>cT1B), the emerging strategies have included preoperative chemotherapy, postoperative adjuvant chemotherapy, and (occasionally) postoperative chemoradiation in various regions. Several novel therapies have been assessed in clinical trials, but only trastuzumab and ramucirumab (alone and in combination with paclitaxel) have shown overall survival advantage. Pembrolizumab has been approved by the US Food and Drug Administration on the basis of response rate only for patients with microsatellite instability (MSI-H) or if PD-L1 expression is positive (≥1% labeling index in tumor/immune cells in the presence of at least 100 tumor cells in the specimen). Nivolumab has been approved in Japan on the basis of a randomized trial showing significant survival advantage for patients who received nivolumab compared with placebo in the third or later lines of therapy. The cure rate of patients with localized GAC in the West is only about 40% and that for metastatic cancer is very poor (only 2-3%). At this stage, much more target discovery is needed through molecular profiling. Personalized therapy of patients with GAC remains a challenge.

Intraperitoneal chemotherapy for gastric cancer with peritoneal metastasis

Peritoneal metastasis is the most frequent pattern of gastric cancer recurrence or metastasis and is a definitive determinant of prognosis. However, an effective means of treating peritoneal disease has not yet been established. Systemic chemotherapy has only a limited effect on peritoneal metastasis, although some progress has been shown in terms of median survival time, especially among patients with a minimal or moderate disease burden. Clinical research related to intraperitoneal administration of anticancer drugs is currently underway. An advantage of intraperitoneal chemotherapy is the ability to achieve high concentrations of anticancer drugs in the peritoneal cavity and the direct exposure of peritoneal deposits and free cancer cells to those drugs. In addition, pharmacokinetic studies with taxanes have shown that these high intraperitoneal drug concentrations are sustained for a considerable length of time, allowing prolonged exposure. As taxanes are the most appropriate drugs for intraperitoneal administration, the development of repeated intraperitoneal chemotherapy using taxanes for gastric cancer peritoneal metastasis-either alone or in combination with systemic chemotherapy-has taken place over the past decade, mostly in Japan. Several phase II trials and a phase III trial have recently demonstrated the efficacy of this therapy, including median survival times of 14.4-24.6 months and one-year overall survival rates of 67-91%. These results may lead to the approval of intraperitoneal taxanes, especially paclitaxel, for official insurance coverage in the near future.

Intraperitoneal free cancer cells in gastric cancer: pathology of peritoneal carcinomatosis and rationale for intraperitoneal chemotherapy/hyperthermic intraperitoneal chemotherapy in gastric cancer

Peritoneal carcinomatosis (PC) is one of the most common causes of death in gastric cancer patients. Intraperitoneal free cancer cells (IFCCs) play a very important role in forming PC, but the administration of intraperitoneal chemotherapy (IPC) and/or hyperthermic intraperitoneal chemotherapy (HIPEC) could be an effective treatment for IFCCs. This review focuses on the origin of IFCCs, the mechanism of PC formatting, the rationale of IPC/HIPEC, and the current clinical trials on IPC/HIPEC to treat advanced gastric cancer patients.