Staging Laparoscopy for Patients with cM0, Type 4, and Large Type 3 Gastric Cancer

Phase I/II Study of Neoadjuvant Chemoradiotherapy Consisting of S-1 and Cisplatin for Patients with Clinically Resectable Type 4 or Large Type 3 Gastric Cancer (OGSG1205)

BACKGROUND

To improve the prognosis of clinically resectable type 4 or large type 3 gastric cancer (GC), we performed a phase I/II study of neoadjuvant-radiotherapy combined with S-1 plus cisplatin.

PATIENTS AND METHODS

Phase I, with a standard 3 + 3 dose-escalation design, was performed to define the recommended phase II dose. Efficacy and safety were evaluated in phase II. The three dose levels were as follows: level 0, S-1 60 mg/m2 on days 1-14 plus cisplatin 60 mg/m2 on day 1; level 1, S-1 80 mg/m2 on days 1-14 plus cisplatin 60 mg/m2 on day 1; and level 2, S-1 80 mg/m2 on days 1-14 and 22-35, plus cisplatin 60 mg/m2 on days 1 and 22. The starting dose was level 1. Radiotherapy was delivered at a total dose of 40 Gy in fractions for 4 weeks.

RESULTS

A total of six patients were enrolled in the phase I study. Dose-limiting toxicity was observed at level 2; level 1 was established as the recommended phase II dose. In phase II, 20 patients were enrolled from November 2012 to April 2018. Grade 3/4 leukopenia and nonhematologic adverse events occurred in 35% and 5% of the patients, respectively. In total, 19 patients underwent the protocol surgery; 2 (10.5%) achieved a pathological complete response. There were no treatment-related deaths; 3- and 5-year overall survival rates were 70.0 and 50.0%, respectively.

CONCLUSIONS

Neoadjuvant chemoradiotherapy with S-1 plus cisplatin is a safe and promising treatment for clinically resectable type 4 or large type 3 GC.

Oncological similarities between large type 3 and type 4 tumors in patients with resectable gastric cancer: a propensity score-matched analysis of a multi-institutional dataset

BACKGROUND

Large type 3 (diameter ≥ 8 cm) and type 4 gastric cancers have been arbitrarily combined in Japan as a single entity. However, whether these two types are oncologically similar remain unclear. This study aimed to clarify this issue.

METHODS

In this retrospective study, we analyzed a database of 3,575 patients from nine institutions who underwent gastrectomy between 2010 and 2014. Using propensity scores to balance significant variables, we compared prognoses and tumor recurrences.

RESULTS

Of patients with clinical T3/T4 who underwent R0 resection, 75 and 73 had large type 3 and 4 tumors, respectively. Patients with type 4 tumors had significantly lower overall survival rates than those of patients with large type 3 tumors (hazard ratio [HR] 1.77; 95% confidence interval [CI] 1.14-2.74). However, among the large type 3 tumors, a remarkable difference in prognosis was observed between the differentiated and undifferentiated histological types. A comparison was made between large type 3 with undifferentiated phenotype and type 4, each with 39 patients after propensity score matching. Outcomes in both groups were similar in terms of overall survival (HR 1.28; 95% CI 0.73-2.25) and relapse-free survival (HR 1.34; 95% CI 0.80-2.27). No statistically significant differences were observed in the incidence of peritoneal recurrence (35.9% vs. 46.1%, P = 0.36) and lymph node recurrence (25.6% vs. 12.8%, P = 0.15).

CONCLUSIONS

Large type 3 tumors with undifferentiated phenotype and type 4 tumors were oncologically similar. This subgroup could be considered as a new entity for future clinical trials.

Transcriptomics-based liquid biopsy panel for early non-invasive identification of peritoneal recurrence and micrometastasis in locally advanced gastric cancer

BACKGROUND

This study aimed to develop a novel six-gene expression biomarker panel to enhance the early detection and risk stratification of peritoneal recurrence and micrometastasis in locally advanced gastric cancer (LAGC).

METHODS

We used genome-wide transcriptome profiling and rigorous bioinformatics to identify a six-gene expression biomarker panel. This panel was validated across multiple clinical cohorts using both tissue and liquid biopsy samples to predict peritoneal recurrence and micrometastasis in patients with LAGC.

RESULTS

Through genome-wide expression profiling, we identified six mRNAs and developed a risk prediction model using 196 samples from a surgical specimen training cohort. This model, incorporating a 6-mRNA panel with clinical features, demonstrated high predictive accuracy for peritoneal recurrence in gastric cancer patients, with an AUC of 0.966 (95% CI: 0.944-0.988). Transitioning from invasive surgical or endoscopic biopsy to noninvasive liquid biopsy, the model retained its predictive efficacy (AUC = 0.963; 95% CI: 0.926-1.000). Additionally, the 6-mRNA panel effectively differentiated patients with or without peritoneal metastasis in 95 peripheral blood specimens (AUC = 0.970; 95% CI: 0.936-1.000) and identified peritoneal micrometastases with a high efficiency (AUC = 0.941; 95% CI: 0.874-1.000).

CONCLUSIONS

Our study provides a novel gene expression biomarker panel that significantly enhances early detection of peritoneal recurrence and micrometastasis in patients with LAGC. The RSA model's predictive capability offers a promising tool for tailored treatment strategies, underscoring the importance of integrating molecular biomarkers with clinical parameters in precision oncology.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with gastric cancer

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with gastric cancer (GC), published in late 2022 and the updated ESMO Gastric Cancer Living Guideline published in July 2023, were adapted in August 2023, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with GC. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with GC representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), coordinated by ESMO and the Japanese Society of Medical Oncology (JSMO). The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian regions represented by the 10 oncological societies. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with GC across the different regions of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling and age and stage at presentation. Attention is drawn to the disparity in the drug approvals and reimbursement strategies, between the different regions of Asia.

STAGING LAPAROSCOPY IS STILL A VALUABLE TOOL FOR OPTIMAL GASTRIC CANCER MANAGEMENT

BACKGROUND

Complete surgical resection is the main determining factor in the survival of advanced gastric cancer patients, but is not indicated in metastatic disease. The peritoneum is a common site of metastasis and preoperative imaging techniques still fail to detect it.

AIM

The aim of this study was to evaluate the role of staging laparoscopy in the staging of advanced gastric cancer patients in a Western tertiary cancer center.

METHODS

A total of 130 patients with gastric adenocarcinoma who underwent staging laparoscopy from 2009 to 2020 were evaluated from a prospective database. Clinicopathological characteristics were analyzed to identify factors associated with the presence of peritoneal metastasis and were also evaluated the accuracy and strength of agreement between computed tomography and staging laparoscopy in detecting peritoneal metastasis and the change in treatment strategy after the procedure.

RESULTS

The peritoneal metastasis was identified in 66 (50.76%) patients. The sensitivity, specificity, and accuracy of computed tomography in detecting peritoneal metastasis were 51.5, 87.5, and 69.2%, respectively. According to the Kappa coefficient, the concordance between staging laparoscopy and computed tomography was 38.8%. In multivariate analysis, ascites (p=0.001) and suspected peritoneal metastasis on computed tomography (p=0.007) were statistically correlated with peritoneal metastasis. In 40 (30.8%) patients, staging and treatment plans changed after staging laparoscopy (32 patients avoided unnecessary laparotomy, and 8 patients, who were previously considered stage IVb by computed tomography, were referred to surgical treatment).

CONCLUSION

The staging laparoscopy demonstrated an important role in the diagnosis of peritoneal metastasis, even with current advances in imaging techniques.

Situación actual de la laparoscopía de estadificación en pacientes con cáncer gástrico en Colombia: ¿Cómo lo estamos haciendo?

Introducción. La laparoscopía de estadificación permite identificar con gran precisión el compromiso locorregional avanzado y metastásico a peritoneo en los pacientes con cáncer gástrico. Las guías internacionales aún difieren en las indicaciones para incluir este procedimiento como parte del proceso de estadificación. Métodos. Se diseñó una encuesta dirigida a cirujanos residentes en Colombia, sobre el uso de la laparoscopía de estadificación en los pacientes con cáncer gástrico. Se analizaron los resultados y con base en la evidencia disponible se proponen algunas pautas en las indicaciones y técnica del procedimiento. Resultados. Respondieron la encuesta 74 cirujanos; el 43,8 % considera que el objetivo de la laparoscopía de estadificación es descartar la carcinomatosis peritoneal. El 54,1 % realiza el procedimiento en estadios tempranos, sin embargo, el 48,6 % considera realizarla solo en pacientes con sospecha de carcinomatosis por imágenes. Las áreas evaluadas con mayor frecuencia por los cirujanos (más del 85 %) son la superficie hepática, las cúpulas diafragmáticas, los recesos parietocólicos y la pelvis. Las zonas evaluadas en menor frecuencia son la válvula ileocecal (40,5 %) y el ligamento de Treitz (39 %). El 33 % de los cirujanos no toma rutinariamente citología peritoneal. Conclusión. Este trabajo muestra la tendencia de los cirujanos en el uso de la laparoscopía de estadificación en pacientes con cáncer gástrico. A pesar de encontrar resultados muy positivos en relación con las indicaciones y técnica del procedimiento, es necesario analizar la evidencia disponible para su uso según cada escenario y mejorar la sistematización del procedimiento.

Phase 2 randomized controlled trial of intravenous or intraperitoneal paclitaxel plus mFOLFOX6 vs. mFOLFOX6 as first-line treatment of advanced gastric cancer

Objective

We conducted a phase 2 trial to compare the safety and efficacy of intravenous paclitaxel or intraperitoneal paclitaxel plus mFOLFOX6 vs. mFOLFOX6 in untreated advanced gastric cancer.

Methods

Participants with untreated advanced gastric cancer were randomly assigned (1:1:1) to: intravenous paclitaxel 135 mg/m² or intraperitoneal paclitaxel 80 mg/m² plus mFOLFOX6 omitting bolus fluorouracil; or mFOLFOX6 (oxaliplatin 85 mg/m², leucovorin 400 mg/m², fluorouracil 400 mg/m² bolus, fluorouracil 2,400 mg/m² 46-h continuous infusion). Treatment was every 14 days for up to 9 cycles followed by S-1 maintenance. The primary outcome was progression-free survival.

Results

Of 90 enrolled participants, 30 in the intravenous paclitaxel group, 29 in the intraperitoneal paclitaxel group, and 30 in the mFOLFOX6 group were included in the analyses. The median progression-free survival was 6.52, 5.83, and 4.55 months, respectively, for the intravenous paclitaxel group, intraperitoneal paclitaxel group, and mFOLFOX6 group. The hazard ratios were 0.56 (95% CI: 0.33–0.94; p = 0.026) and 0.56 (95% CI: 0.33–0.96; p = 0.037), respectively, for the intravenous paclitaxel group and the intraperitoneal paclitaxel group vs. the mFOLFOX6 group. The most common grade 3/4 adverse events for the intravenous paclitaxel group, intraperitoneal paclitaxel group, and mFOLFOX6 group, respectively, were neutropenia (30.0%, 34.5%, 33.3%), diarrhea (13.3%, 20.7%, 13.3%), and leukopenia (10.0%, 13.8%, 10.0%). No treatment-related death occurred.

Conclusion

The findings of this phase 2 trial suggest that adding intravenous paclitaxel or intraperitoneal paclitaxel to mFOLFOX6 for untreated advanced gastric cancer improved progression-free survival with manageable adverse events.

Intraperitoneal therapy for gastric cancer peritoneal carcinomatosis

INTRODUCTION

Gastric adenocarcinoma (GAC) is one of the most aggressive malignancies worldwide and has a poor prognosis. Multidisciplinary therapies are used in its treatment, but the prognosis for GAC patients with peritoneal metastases (PM) remains poor and there is no effective established approach.

AREAS COVERED

This review summarizes the results of recent clinical studies and recent advances in the management, including surgery, chemotherapy, targeted therapy, and immunotherapy. In this review, keywords were searched in combination with 'peritoneal carcinomatosis' and 'gastric cancer' in PubMed, and then studies that evaluated peritoneal carcinomatosis associated with gastric cancer were identified through reading them. Several studies were quoted at second hand. Despite recent advances in therapeutic approaches such as systemic chemotherapy, immunotherapy, intraperitoneal chemotherapy, debulking surgery, thermal hyperthermic intraperitoneal chemotherapy, pressurized intraperitoneal aerosol chemotherapy, immunotherapy, and best supportive therapy, further studies are necessary. This review also summarizes molecular biology of GAC patients with PM.

EXPERT OPINION

Each modality is advancing and some have shown therapeutic effects, but none have become standard treatments that exhibit remarkable effects. To improve the prognosis of GAC patients with PM, large-scale clinical trials and further basic research are required.

Usefulness of Diagnostic Staging Laparoscopy for Advanced Gastric Cancer

BACKGROUND

For advanced gastric cancer (AGC), peritoneal metastasis is the most common determinant of unresectability, but accurate preoperative diagnosis for peritoneal metastasis is challenging. Staging laparoscopy (SL) can detect unsuspected peritoneal metastasis. This study retrospectively evaluated the utility of SL and its indication in patients with AGC.

METHODS

In this study, we enrolled 114 patients with pathologically diagnosed gastric adenocarcinoma who underwent SL.

RESULTS

Of the 114 patients, 43 (37.7%) had peritoneal metastasis (P1 or CY1). Higher age, larger tumor size, type 4 GC, deeper tumor depth, elevated CA125, and ascites findings in preoperative CT were found to be significant predictors of peritoneal metastasis. In multivariate analysis, peritoneal metastasis was associated with type 4 GC (odds ratio [OR]: 6.11; 95% confidence interval [CI]: 1.87-19.8; P < .01) and ascites in CT (OR: 4.25; 95% CI: 1.48-12.1; P < .01).

CONCLUSIONS

Staging laparoscopy is an effective tool to detect peritoneal metastasis from AGC. It can increase the curative resection rate and decrease unnecessary laparotomies.

Matrix metalloprotease-14 is a target enzyme for detecting peritoneal metastasis in gastric cancer

BACKGROUND

Accurate diagnosis of peritoneal metastasis in gastric cancer (GC) is important to determine the appropriate treatment. This study aimed to examine whether matrix metalloprotease-14 (MMP-14) was a candidate enzyme in fluorescence imaging for the diagnosis of peritoneal metastasis in GC.

METHODS

GC and normal peritoneal (NP) tissues from 96 and 20 patients, respectively were evaluated for MMP-14 expression. Live cell imaging of GC cell lines (NUGC4, MKN45, MKN74, HGC-27, and Kato-III) was performed using the MMP-14-activatable fluorescence probe; BODIPY-MMP. Furthermore, the overall survival (OS) was calculated in all patients (n = 96).

RESULTS

MMP-14 expression was significantly higher in GC tissues (median: 3.57 ng/mg protein; range:0.64-24.4 ng/mg protein) than in NP tissues (median: 1.34 ng/mg protein; median: 0.53-3.09 ng/mg protein) (P < 0.01). Receiver operating characteristic curves showed that the area under the curve, sensitivity, and specificity were 0.907, 84.4%, and 90.0%, respectively. In live cell imaging using the BODIPY-MMP, fluorescence was observed in five GC cell lines. In the analysis of OS, the high expression of the MMP-14 group had a significantly poorer OS rate than the low expression of the MMP-14 group (P = 0.02). In the multivariate analyses, MMP-14 expression was an independent risk factor for OS (hazard ratio: 2.33; 95 % confidence interval: 1.05-5.45; P = 0.04).

CONCLUSION

MMP-14 is a promising enzyme in intraoperative fluorescence imaging for peritoneal metastasis in GC, especially in patients with poor prognosis.

β-Galactosidase is a target enzyme for detecting peritoneal metastasis of gastric cancer

Diagnosis of peritoneal metastasis in gastric cancer (GC) is essential for determining appropriate therapeutic strategies and avoiding non-essential laparotomy or gastrectomy. Recently, a variety of activatable fluorescence probes that can detect enzyme activities have been developed for cancer imaging. The aim of this study was to identify the key enzyme involved in peritoneal metastasis in GC. The enzymatic activity of gamma-glutamyl transpeptidase, dipeptidyl peptidase IV, and β-galactosidase (β-Gal) was assessed in lysates prepared from preserved human GC (n = 89) and normal peritoneal (NP; n = 20) samples. β-Gal activity was significantly higher in the human GC samples than in NP samples, whereas no differences were observed in the activities of the other enzymes. Therefore, we used SPiDER-βGal, a fluorescent probe that can be activated by β-Gal, for imaging GC cell lines, peritoneal metastasis in a mouse model, and fresh human resected GC samples (n = 13). All cell lines showed fluorescence after applying SPiDER-βGal, and metastatic nodules in the mice gradually developed high fluorescence that could be visualized with SPiDER-βGal. The human GC samples showed significantly higher fluorescence than NP samples. β-Gal is a useful target enzyme for fluorescence imaging of peritoneal metastasis in GC.

The role of laparoscopic staging for the management of gastric cancer

AİM Staging laparoscopy enables us to perform palliative treatment, neo-adjuvant therapy for curative resection or direct curative resection and making a decision with minimal morbidity by avoiding from unnecessary laparotomies. In the present study, the importance of staging lapafoscopy was retrospectively investigated by using clinical and pathologic data. METHODS Data of 70 out of 350 patients who underwent diagnostic laparoscopy due to gastric cancer at Surgical Oncology department between August 2013 and January 2020 were retrospectively analyzed. RESULTS Peritoneal biopsy was positive for malignity in 41 (58.5%) and negative in 29 (41.5%) of the patients who underwent SL. Peritoneal cytology (PC) results were negative in 32 (45.7%) patients and positive in 38 (54.3%) patients. Peritoneal biopsy and cytology results were concurrently positive in 35 patients and concurrently negative in 26 patients. CONCLUSİONS In conclusion, even the most developed imaging methods cannot provide 100% staging, therefore SL plays an important role in treatment of gastric cancer and laparoscopic staging is essential as a simple, inexpensive, safe and well tolerated method in patients who have the suspicion of peritoneal disease and who cannot be clearly evaluated with pre-operative methods.

Phase II Study of Preoperative Intra-Arterial Epirubicin, Etoposide, and Oxaliplatin Combined with Oral S-1 Chemotherapy for the Treatment of Borrmann Type 4 Gastric Cancer

Purpose

A phase II study was conducted to evaluate the safety and efficacy of preoperative, intra-arterial perfusion of epirubicin, etoposide, and oxaliplatin combined with oral chemotherapy S-1 (SEEOX) for the treatment of type 4 gastric cancer.

Materials and Methods

A single-center, single-arm phase II trial was conducted on 36 patients with histologically proven type 4 gastric cancer without distant peritoneal or organ metastasis. Patients received 3, 21-day courses of SEEOX preoperative chemotherapy. The primary endpoint was overall survival (OS) and the secondary outcomes assessed were chemotherapeutic response, radical resection rate, pathological regression, toxicities, postoperative morbidity, and mortality.

Results

All patients were at an advanced stage of cancer (stage III or IV) and completed the entire course of treatment. Based on changes in tumor volume and peritoneal metastasis, the objective response rate was 55.6% (20/36; 95% confidence interval [CI], 38.5%–72.6%) and the disease control rate was 69.4% (25/36; 95% CI, 53.6%–85.3%). The radical resection rate was 75% (27/36; 95% CI, 60.1%–89.9%) and the proportion of R0 resections was 66.7% (21/36; 95% CI, 50.5%–82.8%). The pathological response rate was 33.3%, of which 13.9% showed complete pathological regression. The median survival was 27.1 months (95% CI, 22.24–31.97 months), and the 2-year OS was 48.5% (95% CI, 30.86%–66.1%).

Conclusions

Preoperative SEEOX is a safe and effective treatment for type 4 gastric cancer. Based on these preliminary data, a phase III study will be conducted to confirm the superiority of this regimen over standard treatment.

Trial Registration

ClinicalTrials.gov Identifier: NCT02949258

Peritoneal dissemination of breast cancer diagnosed by laparoscopy

The accuracy of modern imaging techniques for the diagnosis of peritoneal carcinomatosis is poor. A breast cancer patient with a high serum CA15-3 level did not receive a definitive diagnosis of peritoneal dissemination by imaging examination and then underwent laparoscopy. Pathological examination showed peritoneal dissemination of breast cancer, but the biological markers were different from the primary lesion: ER(−), PgR(−), and Her2:3 +. T-DM1 therapy was very effective, and her systemic symptoms disappeared. Since biomarkers of metastatic lesions may sometimes change, laparoscopic biopsy is very important and useful.

Clinical Significance of Conversion Surgery for Gastric Cancer with Peritoneal Dissemination: A Retrospective Study

OBJECTIVE

Although chemotherapy has been clinically recommended as the initial treatment for patients with peritoneal dissemination of gastric cancer, poor prognosis has been noted among the same patients. However, the prognostic significance of conversion surgery after chemotherapy remains unclear. The present study therefore aimed to assess the clinical impact of conversion surgery among patients with peritoneal dissemination of gastric cancer.

METHODS

A total of 93 patients with peritoneal dissemination of gastric cancer undergoing chemotherapy between February 2002 and October 2019 were retrospectively enrolled and subsequently divided into progressive disease (PD) and non-PD groups based on tumor response to chemotherapy.

RESULTS

Among the included patients, 17 developed distant metastases at another site besides peritoneal dissemination. Based on tumor response, 24 and 69 patients were determined to have PD and non-PD, respectively, with the former having significantly poorer prognosis than the latter (p < 0.0001). A total of 19 patients underwent conversion surgery after chemotherapy, with the presence or absence of conversion surgery being significantly correlated with age, first-line chemotherapy regimen, and tumor response (p = 0.0134, p = 0.0337, and p = 0.0024, respectively). Patients in the non-PD group who underwent conversion surgery or chemotherapy alone had 3-year overall survival rates of 55.6 and 6.6%, respectively. Multivariate analysis identified conversion surgery alone as an independent prognostic factor in the non-PD group (p < 0.0001).

CONCLUSION

Our retrospective study demonstrated that conversion surgery for gastric cancer with peritoneal dissemination might improve the prognosis of responders who developed no peritoneal dissemination after chemotherapy.

Metabolomic profiling of gastric cancer tissues identified potential biomarkers for predicting peritoneal recurrence

BACKGROUND

Metabolomics is useful for analyzing the nutrients necessary for cancer progression, as the proliferation is regulated by available nutrients. We studied the metabolomic profile of gastric cancer (GC) tissue to elucidate the associations between metabolism and recurrence.

METHODS

Cancer and adjacent non-cancerous tissues were obtained in a pair-wise manner from 140 patients with GC who underwent gastrectomy. Frozen tissues were homogenized and analyzed by capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). Metabolites were further assessed based on the presence or absence of recurrence.

RESULTS

Ninety-three metabolites were quantified. In cancer tissues, the lactate level was significantly higher and the adenylate energy charge was lower than in non-cancerous tissues. The Asp, β-Ala, GDP, and Gly levels were significantly lower in patients with recurrence than in those without. Based on ROC analyses to determine the cut-off values of the four metabolites, patients were categorized into groups at high risk and low risk of peritoneal recurrence. Logistic regression and Cox proportional hazard analyses identified β-Ala as an independent predictor of peritoneal recurrence (hazard ratio [HR] 5.21 [95% confidence interval 1.07-35.89], p = 0.029) and an independent prognostic factor for the overall survival (HR 3.44 [95% CI 1.65-7.14], p < 0.001).

CONCLUSIONS

The metabolomic profiles of cancer tissues differed from those of non-cancerous tissues. In addition, four metabolites were significantly associated with recurrence in GC. β-Ala was both a significant predictor of peritoneal recurrence and a prognostic factor.

Gastric Cancer with Radiographically Occult Metastatic Disease: Biology, Challenges, and Diagnostic Approaches

Gastric adenocarcinoma is an aggressive cancer that demonstrates heterogeneous biology depending on patient ethnicity, tumor location, tumor type, and genetic profile. It remains the third leading cause of cancer deaths worldwide and was estimated to result in 782,000 deaths in 2018. Challenges exist in accurately assessing the disease burden, as available radiological staging often underestimates metastatic disease. This diagnostic handicap, along with the poor understanding of the heterogeneous biology of gastric cancer, has hindered the development of effective therapeutic solutions and thus halted improvement in patient outcomes over the last few decades. The management of occult peritoneal disease is complicated, as most patients are understaged by standard imaging studies and therefore thought to have local diseases. In this article, we systematically review recent literature on the limitations that are associated with standard radiographic staging, discuss recent molecular biology advances to better identify and diagnose occult peritoneal disease, and propose possible management strategies to approach this complicated clinical problem.

Conversion therapy for peritoneal lavage cytology-positive type 4 and large type 3 gastric cancer patients selected as candidates for R0 resection by diagnostic staging laparoscopy

BACKGROUND

The long-term outcomes of type 4 and large type 3 gastric cancer patients with positive peritoneal lavage cytology (CY1) remain unsatisfying. We evaluated our treatment strategy of conversion therapy for CY1 patients without peritoneal dissemination (P0).

METHODS

Diagnostic staging laparoscopy (DSL) was performed before treatment. Chemotherapy was applied for DSL-diagnosed P0CY1. The re-evaluation of peritoneal metastasis by staging laparoscopy (re-SL) was performed when a response to chemotherapy was identified by gastroscopy and/or CT. Gastrectomy with radical lymphadenectomy was applied as conversion therapy when peritoneal lavage cytology-negative (CY0) and P0 were diagnosed with re-SL, with the aim of achieving R0 resection. Chemotherapy was continued as palliative treatment in patients for whom re-SL was not applicable or when re-SL did not confirm P0CY0. The long-term outcomes were retrospectively evaluated.

RESULTS

Between 2009 and 2015, 214 patients with type 4 and large type 3 gastric cancer underwent DSL in the Cancer Institute Hospital. Thirty-nine patients were initially diagnosed with P0CY1. Seven patients received palliative gastrectomy first due to outlet obstruction or other reasons. Thirty-two patients received chemotherapy first. Among them, 13 patients underwent gastrectomy as conversion therapy and 19 were treated with palliative chemotherapy. The 3-year survival rate of patients who underwent conversion therapy, palliative chemotherapy and palliative gastrectomy was 76.9% [95% confidence interval (CI) 47.8-92.4%], 10.5% (95% CI 1.9-42.3%), and 0%, respectively.

CONCLUSION

Conversion therapy might be a promising treatment for P0CY1 type 4 and large type 3 gastric cancer patients. Re-SL was useful for selecting candidates for R0 resection.

Conversion Surgery in Metastatic Gastric Cancer and Cancer Dormancy as a Prognostic Biomarker

The role of conversion surgery in metastatic gastric cancer remains unclear. Cancer dormancy markers might have a role in predicting the survival in patients with conversion surgery. We identified 26 patients who went through conversion surgery, i.e., a curative-intent gastrectomy with metastasectomy after chemotherapy in initially metastatic gastric cancer. As controls, 114 potential candidates for conversion surgery who only received chemotherapy were included for the propensity score matching. Conversion surgery showed a significantly longer overall survival (OS) compared with only palliative chemotherapy (median-43.6 vs. 14.0 months, respectively, p < 0.001). This better survival in the conversion surgery group persisted even after propensity matching (p < 0.001), and also when compared to patients with tumor response over 5.1 months in the chemotherapy only group (p = 0.005). In the conversion surgery group, OS was longer in patients with R0 resection (22/26, 84.6%) than without R0 resection (4/26, 15.4%) (median-not reached vs 22.1 months, respectively, p = 0.005). Although it should be interpreted with caution due to the primitive analysis in a small population, the positive expression of NR2F1 showed a longer duration of disease-free survival (DFS) after conversion surgery (p = 0.016). In conclusion, conversion surgery showed a durable OS even in patients with initially metastatic gastric cancer when R0 resection was achieved after chemotherapy.

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.

Conversion Surgery for Gastric Cancer with Peritoneal Metastasis Based on the Diagnosis of Second-Look Staging Laparoscopy

BACKGROUND

Patients with positive peritoneal cytology (CY1) or peritoneal dissemination (P1) have significantly poor prognosis. We performed pre-therapeutic staging laparoscopy (SL) to diagnose peritoneal metastasis for patients with advanced gastric cancer. When peritoneal metastasis disappears by chemotherapy for patients with CY1 or P1, we have intention to perform conversion surgery (CS). This study aims to clarify the clinical significance of CS for such patients.

METHODS

We retrospectively analyzed clinical outcomes of 115 patients with advanced gastric cancer (large type 3, type 4, serosa-invasion) who underwent SL between 2005 and 2014. Disappearance of peritoneal metastasis was confirmed by second-look SL.

RESULTS

CY0P0, CY1P0, and P1 were found in 56, 26, and 33 patients, respectively. In patients with CY1P0, 12 patients (66.7%) underwent CS (R0) as peritoneal cytology turned negative. All cases received S-1-based regimens, with median five treatment courses. The survival of patients with CS was significantly longer than those without CS (median survival time (MST); 41 vs. 11 months, respectively, P < 0.001). We observed no difference in overall survival between patients who underwent CS and patients with CY0P0 at the first SL (P = 0.913). All patients with P1 received chemotherapy. As peritoneal metastasis of five patients (15.2%) disappeared by chemotherapy, those patients underwent the CS (R0). The survival of patients who underwent CS was significantly longer than those who did not (MST; 31 vs. 10 months, respectively, P = 0.034).

CONCLUSION

This study suggests that conversion surgery contributes to improvement in survival of patients with peritoneal metastasis.

Role of staging laparoscopy for gastric cancer patients

Staging laparoscopy (SL) is frequently carried out in patients with advanced gastric cancer. However, some clinical questions are being debated and consensus must be obtained. With this aim, a literature search of PubMed/MEDLINE was carried out using the keywords "gastric cancer," "SL," and "diagnostic laparoscopy". Articles published online up to February 2019 were analyzed, focusing on the following questions. (i) What is an adequate indication for SL? (ii) How do you carry out SL? (iii) Does SL provide accurate information about peritoneal dissemination? (iv) Is the yield of SL different by tumor location? (v) Is SL a safe procedure? (vi) Is "repeat SL" needed? (vii) Does SL provide oncological benefit? Results provided the following responses: (i) In Western countries, clinically resectable advanced tumor is an indication for SL. Terms to be introduced for adequate indication include "location," "type 4 (linitis feature)," "large tumor," "equivocal computed tomography (CT] findings," and "lymph node swelling". (ii) Exploration of the entire peritoneal cavity is preferable. (iii) Detection rate of peritoneal disease is 43%-52% in Japanese institutions and 7.8%-40% in other countries. False-negative findings during SL were 0%-17%, and 10%-13% when limited to cytology. (iv) Yield of SL was higher in gastric cancer compared with esophagogastric junctional tumor. (v) SL-related complications were estimated to occur in 0.4%. (vi) Repeat SL is important after treatment. (vii) If the efficacy of neoadjuvant chemotherapy for patients with P0CY1 is established, SL can provide oncological benefit. SL can be carried out safely and effectively. Considering the prevalence of neoadjuvant treatment, the role of SL will become more important.

Impact of preoperative wait time on survival in patients with clinical stage II/III gastric cancer

BACKGROUND

Preoperative wait time is affected by various factors, and a certain time is needed before surgery. There is a concern that cancer treatment delay can lead to poor survival. The present study aimed to evaluate the impact of preoperative wait time on survival in patients with clinical stage (cStage) II/III gastric cancer.

METHODS

The study included patients with cStage II/III primary gastric cancer undergoing surgery between 2002 and 2012. Preoperative wait time was defined as the time from endoscopy for initial diagnosis to surgery. Patients were divided into the following three groups according to wait time: short wait group (≤ 30 days), intermediate wait group (> 30 and ≤ 60 days), and long wait group (> 60 and ≤ 90 days). Patient characteristics and survival were compared among the groups.

RESULTS

This study included 467 male (67%) and 229 female (33%) patients, and the median patient age was 67 years. The numbers of cStage II and III patients were 332 (48%) and 364 (52%), respectively. The median wait time was 45 days. The body mass index was lower in the short wait group than in the other groups. A shorter wait time tended to be associated with a more advanced cStage. Although survival was significantly worse in the short wait group than in the long wait group, wait time was not identified as an independent prognostic factor in multivariate analysis.

CONCLUSION

Preoperative wait time up to 90 days does not affect survival in patients with cStage II/III gastric cancer.

The neutrophil/lymphocyte ratio as a predictor of peritoneal metastasis during staging laparoscopy for advanced gastric cancer: a retrospective cohort analysis

BACKGROUND

The use of staging laparoscopy (SL) has become widespread in patients with advanced gastric cancer (GC). This study aimed to evaluate the predictive value of the neutrophil/lymphocyte ratio (NLR) for the presence of peritoneal metastasis during staging laparoscopy in patients with advanced GC.

METHODS

This retrospective analysis was performed in 35 patients with advanced GC who underwent SL at Kanazawa Medical University Hospital between January 2009 and December 2017. Clinicopathological characteristics were examined and multivariate analyses were performed to identify preoperative laboratory parameters that were independently associated with the presence of peritoneal metastasis or cytological malignancy (P/CY positive) during SL.

RESULTS

A P/CY-positive result was confirmed during SL in 16 patients (45.7%). Patients with type 4 or diffuse type 3 tumors showed a significantly higher P/CY-positive rate than those with other tumor types (58.3% vs. 18.2%, P = 0.02). In the univariate analysis for preoperative laboratory parameters, NLR (P < 0.0001) and total protein (P = 0.03) and albumin (P = 0.04) levels were significantly correlated with a P/CY-positive result. On multivariate analysis, NLR was significantly correlated with a P/CY-positive result (P = 0.0002). In patients with type 4 or diffuse type 3 tumors, a high NLR (> 3.5) was associated with a significantly higher P/CY-positive rate than a low NLR (≤ 3.5) (83.3% vs. 33.3%, P = 0.01). Moreover, in patients without type 4 or diffuse type 3 tumors, the P/CY-positive rates were 100% and 0% in patients with NLR > 3.5 and NLR ≤ 3.5, respectively.

CONCLUSIONS

The preoperative NLR was a significant independent predictor of the presence of peritoneal metastasis during SL. Regardless of tumor type, patients with a high NLR could be reasonable candidates for SL. On the other hand, non-diffuse type tumor accompanied by a low NLR may not need to undergo SL.

"Four-Step Procedure" of laparoscopic exploration for gastric cancer in West China Hospital: a retrospective observational analysis from a high-volume institution in China

BACKGROUND

The preoperative work-up has limitations on finding peritoneal dissemination (PD) in gastric cancer patients. Laparoscopic exploration (LE) can discover radiographically occult PD, obtain accurate stage and avert futile laparotomy. The aim of our study was to introduce "Four-Step Procedure" LE in West China Hospital and further evaluate its safety and feasibility.

METHODS

We conducted a retrospective analysis on 165 patients from July 2016 to December 2017 who underwent "Four-Step Procedure" LE in gastrointestinal surgery department of West China Hospital. All the patients were diagnosed with gastric adenocarcinoma without explicit distant metastasis through Computed Tomography and/or Gastrointestinal Ultrasonography. Peritoneal lavage cytological examination (CY) was routinely performed during LE in our research. The "Four-Step" technical process of LE was introduced comprehensively. The clinicopathologic features and the presence of PD or CY at LE were analyzed, and the stratified analysis by cT and cN stages on the proportion of P1 and/or CY1 was also reported in this study.

RESULTS

Total of 165 patients accepted LE in our study, among these patients: 27 (16.4%) patients with P1 and/or CY1: 19 (11.5%) patients were found PD (P1), 17 (10.3%) patients with positive cytological examination (CY1) and 9 (3.6%) patients with P1Cy1. The stratified analysis by cT stage indicated that there was no P1 and/or Cy1 in cT1-cT2 stages, 1 (2.7%) patient with P1 and 1 (2.7%) with Cy1 in cT3 stage, 18 (20.0%) patients with P1 and 16 (17.8%) with Cy1 in cT4 stage. After LE, there were 74 (44.8%) patients underwent laparoscopic assistant gastrectomy, 25 (15.2%) patients with open gastrectomy, 50 (30.3%) patients with neoadjuvant chemotherapy and 16 (9.7%) patients with palliative chemotherapy and/or conversion therapy.

CONCLUSION

"Four-Step Procedure" LE is reliable and feasible for gastric cancer. From our study, LE has unique superiority on ascertaining PD and cytological examination and LE should be recommended in cT4 stage gastric cancer before resection.

The Yield of Staging Laparoscopy in Gastric Cancer is Affected by Racial and Ethnic Differences in Disease Presentation

BACKGROUND

Gastric cancer is a heterogeneous disease with variable presentation between racial and ethnic groups. Staging laparoscopy (SL) detects occult metastases not visible on cross-sectional imaging and therefore improves staging. It remains unclear how differences in race and ethnicity affect disease presentation and the yield of SL.

METHODS

We performed a retrospective review of a prospectively maintained database to identify patients with gastric cancer treated with curative intent at our institutions from 2008 to 2015.

RESULTS

Hispanic patients presented at an earlier mean age (55.5 ± 11.9 years) compared with Asian (59.8 ± 13.9 years), African American (61.0 ± 10.0 years), and white patients (61.7 ± 12.5 years; p = 0.046) and with more locally advanced disease (clinical stage T3/T4 or node positive; Hispanic 87%; African American 79%; white 68%, Asian 55%; p = 0.03). SL identified 42 patients (34%) with occult metastatic disease. Hispanics were more likely to have a positive SL (44%) than white patients (21%; p = 0.04). On univariate analysis, Hispanic ethnicity, clinical T3/T4, positive nodal disease, signet ring cells, and poor differentiation were predictors of a positive SL. On multivariable analysis, clinical T3/T4, signet ring cells, and poor differentiation independently predicted radiographically occult disease.

CONCLUSIONS

Hispanic patients presented with more locally advanced disease and were more likely to have occult disease found on SL compared with white patients. Laparoscopy should be used routinely as part of the pretreatment staging evaluation for patients with locally advanced disease as it alters the management in a significant proportion of patients.

Diagnostic staging laparoscopy in gastric cancer: a prospective cohort at a cancer institute in Japan

BACKGROUND

There have been many studies that describe the value of diagnostic staging laparoscopy (DSL) in gastric cancer. However, different studies use different indications, making study results difficult to compare. This study aimed to clarify the diagnostic feasibility of DSL for gastric cancer in a prospective manner and investigated the impact of DSL on clinical decision-making in gastric cancer treatment.

METHODS

The study was a prospective cohort study based at a single institution between January 2010 and December 2013. We treated 2213 patients with potentially resectable gastric cancer during this period. DSL was primarily indicated for asymptomatic patients with: (1) large Borrmann type 3 tumours ≥8 cm, (2) Borrmann type 4 tumours (linitis plastica), (3) bulky lymph nodes or paraaortic lymph node swelling, or (4) clinical suspicion of peritoneal disease. The primary outcome is change in treatment strategy, and the secondary outcomes are diagnostic accuracy of the indications and false negative rate of DSL.

RESULTS

DSL was performed on 156 (7%) of 2213 patients. Of these, peritoneal disease was found in 74 (47%) patients: (1) 56% for large type 3, (2) 54% for type 4, (3) 21% for bulky lymph nodes or paraaortic lymph node swelling, and (4) 20% for suspected peritoneal disease. The diagnostic accuracy of our indication for DSL was 92% for all patients and 74% for patients with cT3/T4 tumours. Among 82 patients without peritoneal disease, 66 patients (81%) underwent subsequent radical gastrectomy; peritoneal disease was discovered intraoperatively for 7 patients at laparotomy, indicating a false negative rate of 11%.

CONCLUSION

We confirmed that DSL performed according to our indication, in the context of gastric cancer, possesses diagnostic feasibility. Approximately half of the patients who underwent DSL consequently avoided unnecessary laparotomy and were able to receive appropriate alternative treatment.

Yield of Staging Laparoscopy for Incurable Factors in Chinese Patients with Advanced Gastric Cancer

BACKGROUND

Although the role of staging laparoscopy (SL) in detecting radiologically occult M1 disease has been widely recognized, it is seldom used in China and its clinical value based on Chinese population has been rarely reported. The aim of this study is to identify the yield of SL for Chinese patients with advanced gastric cancer (AGC) and determine the proportions of patients in whom treatment plan is altered.

MATERIALS AND METHODS

The clinical data were retrospectively collected from 879 AGC patients who underwent SL without any definite signs of disseminated disease on imaging examination. The primary outcomes were the proportions of patients whose laparoscopy identified incurable factors (including M1 diseases and unresectable T4b diseases), and who had their treatment plan altered.

RESULTS

SL revealed incurable factors in 130 (14.8%) patients, including macroscopic peritoneal metastasis (n = 92), positive peritoneal cytology (n = 10), liver metastasis (n = 12), para-aortic lymph node metastasis (n = 1), and unresectable T4b tumor (n = 18). After SL, treatment plans were altered in 123 (14.0%) patients, among which 82 (63.1%) patients were not offered any further procedure and referred for chemotherapy. Among 749 M0 patients who immediately proceeded to radical gastrectomy after SL, new incurable factors were found at subsequent operations in 21 (2.8%) patients. Multivariate analysis showed that tumor size ≥8 cm, Borrmann type III and IV, and tumor invasion of T4a and T4b in preoperative imaging examination were the predictive factors for peritoneal metastasis.

CONCLUSIONS

SL detects additional incurable factors in Chinese AGC patients with potentially resectable disease and optimizes their treatments. A systematic and painstaking inspection of the whole abdominal cavity, including routine entry into the bursa omentalis, is necessary for improving the yield of SL.

Addition of peritonectomy to gastrectomy can predict good prognosis of gastric adenocarcinoma patients with intraoperatively proven single P1/P2 carcinomatosis

This study was to evaluate the prognosis of peritonectomy following gastrectomy for gastric adenocarcinoma patients with intraoperatively proven single P1/P2 carcinomatosis and to define the best therapeutic strategy of the patient cohort. The patients with intraoperatively proven single P1/P2 carcinomatosis from a prospectively maintained database were divided into resection group and non-resection group based on complete gross resection of peritoneal carcinomatosis. From 2005 to 2012, there were 103 patients in the resection group and 122 patients in the non-resection group. There was no difference in morbidity and mortality between groups. The patients did not have improved median survival in P1 carcinomatosis compared to P2 carcinomatosis (15.53 vs 14.80 months, p = 0.450). The median survival was significantly improved in the resection group compared to the patients in the non-resection group (21.07 vs 13.37 months, p < 0.001). The patients undergoing complete gross peritonectomy plus postoperative chemotherapy had a significantly longer median survival than patients who had complete gross peritonectomy alone, patients receiving postoperative chemotherapy alone, and patients receiving neither peritonectomy nor postoperative chemotherapy (27.33 vs 12.00 vs 16.00 vs 10.33 months, p < 0.001). In the multivariate analysis, poor performance status ( p = 0.036), absence of complete gross peritonectomy ( p < 0.001), and lack of postoperative chemotherapy ( p < 0.001) were identified as independently associated with poor survival. The data indicate complete gross peritonectomy following gastrectomy confers a survival benefit to gastric cancer patients with intraoperatively proven single P1/P2 carcinomatosis. In addition, postoperative chemotherapy improves survival regardless of resection of peritoneal carcinomatosis and should be recommended.

Early detection of nonperitoneal recurrence may contribute to survival benefit after curative gastrectomy for gastric cancer

BACKGROUND

There is no evidence that strict follow-up using cross-sectional imaging after curative gastrectomy benefits survival; however, nonperitoneal recurrence detected early might be treated with additional surgery. The present study examined whether early detection of recurrence by imaging modalities could increase survival, particularly in patients with nonperitoneal recurrence.

METHODS

We retrospectively analyzed 218 patients with recurrent gastric cancer after curative gastrectomy performed from 2002 to 2014. The patients were divided into an asymptomatic group (n = 117) and a symptomatic group (n = 101), according to the presence of symptoms at the time of recurrence, to compare clinicopathological characteristics and long-term survival.

RESULTS

Peritoneal recurrence was less frequent in the asymptomatic group (22.2%) than in the symptomatic group (62.4%), the median time to recurrence was shorter (12.7 months vs 18.9 months; P < 0.001), and the median survival time after recurrence was longer (18.7 months vs 7.5 months; P < 0.001). In the asymptomatic group, 10 of 117 patients (8.5%) received additional curative surgery after recurrence. Median overall survival after gastrectomy was not significantly different between the groups (30.1 months for the asymptomatic group vs 30.0 months for the symptomatic group; P = 0.132); however, it was significantly longer among asymptomatic patients with nonperitoneal recurrence compared with symptomatic patients (35.9 months vs 24.0 months; P = 0.039).

CONCLUSIONS

The presence of symptoms at recurrence did not affect survival in patients with recurrent gastric cancer. However, detection of nonperitoneal recurrence before the appearance of symptoms may provide survival benefit. Therefore, regular follow-up, including use of imaging modalities, is recommended.

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

BACKGROUND

Peritoneal carcinomatosis is common after curative resection of gastric cancer. Intraperitoneal administration of paclitaxel (PTX) is known to control ovarian peritoneal metastases.

PATIENTS AND METHODS

Patients with either linitis plastica or T4 cancer with high risk of peritoneal metastasis or recurrence but whose cancer was considered resectable were preregistered. After their cancer had been confirmed intraoperatively as resectable, the patients were randomized into either group A (PTX at 60 mg/m² intraperitoneally on the day of surgery and on days 14, 21, 28, 42, 49, and 56) or group B (PTX at 80 mg/m² administered intravenously by the identical schedule) before being treated by evidence-based chemotherapy. The primary end point was the 2-year survival rate. Safety, the secondary end point, was also analyzed. The study has been registered as UMIN000002957.

RESULTS

Of 177 preregistered patients, 83 underwent treatment (39 by intraperitoneal administration and 44 by intravenous administration). There was no difference in patient demographics between the two groups. The incidences of surgical complications were similar between the groups, except for transient bowel obstruction observed exclusively in group A. The relative dose intensity of PTX was 81.4 % for group A and 76.3 % for group B. There was one death due to pulmonary thrombosis and a case of anaphylaxis that led to termination of the protocol treatment (group B). Other adverse events were mild and manageable.

CONCLUSIONS

Intraperitoneal administration of PTX from the day of gastrectomy did not result in a higher incidence of surgical complications and adverse reactions when compared with intravenous administration of PTX.