Hepatic resection for gastric cancer liver metastases: A systematic review and meta-analysis

Is There a Role for Locoregional Therapies for Non-colorectal Gastrointestinal Malignancies?

The liver is the most common site of metastases from solid gastrointestinal tract tumors. Over the past few decades, the role of locoregional therapies, resection and thermal ablation, for neuroendocrine and colorectal liver metastases has been widely studied. However, for liver metastases originating from other gastrointestinal organs, the role of locoregional treatment remains unclear. This review summarizes and discusses the available evidence regarding benefits, risks, and indications for locoregional therapies for non-colorectal and non-neuroendocrine gastrointestinal liver metastases, highlighting the importance of multidisciplinary approach and patient selection.

The Role of Metastasectomy in Patients with Liver-Only Metastases from Gastric Adenocarcinoma

BACKGROUND

The role of metastasectomy in patients with liver-only metastases from gastric adenocarcinoma remains under investigation. Therefore, we performed a national registry analysis comparing surgical treatment options for patients with gastric adenocarcinoma and liver-only metastases.

PATIENTS AND METHODS

In this retrospective National Cancer Database (2010-2019) study, adults (≥ 18 years) with gastric adenocarcinoma and liver-only metastases (no brain, bone, or lung metastases) were included. Patients were stratified into four groups: no surgical treatment, primary tumor resection (PTR), liver metastasectomy, and PTR with liver metastasectomy. Survival was evaluated using the Kaplan-Meier method, log-rank test, and Cox regression.

RESULTS

Of 10,977 included patients, 93.6% underwent no surgical treatment, 4.6% PTR alone, 0.8% liver metastasectomy alone, and 1.0% both PTR and liver metastasectomy. The median OS after no surgical treatment was 6.5 months, after PTR alone 10.9 months, after liver metastasectomy alone 9.9 months, and after PTR and liver metastasectomy 18.6 months. In multivariable analysis, when adjusting for age, sex, race/ethnicity, insurance status, Charlson-Deyo score, chemotherapy, and radiation, PTR and liver metastasectomy was associated with superior OS compared with no surgical treatment (HR 2.17, 95% CI 1.76-2.69, p < 0.001), PTR alone (HR 1.42, 95% CI 1.12-1.79, p = 0.003), and liver metastasectomy alone (HR 1.96, 95% CI 1.45-2.64, p < 0.001).

CONCLUSIONS

These data suggest that, in highly selected patients with gastric adenocarcinoma and synchronous liver-only metastases and favorable biology, surgical resection might grant a survival advantage.

Single-cell data revealed the regulatory mechanism of TNK cell heterogeneity in liver metastasis from gastric cancer

AIM

The present work set out to classify cell subpopulations related to liver metastasis from gastric cancer (GC) and the mechanisms of their interactions with other immune cell subpopulations.

BACKGROUND

GC is characterized by a high degree of heterogeneity and liver metastasis. Exploring the mechanism of liver metastasis of GC from the perspective of heterogeneity of the tumor microenvironment (TME) might help improve the efficacy of GC treatment.

OBJECTIVE

Based on the cellular subpopulation characteristics of GC with liver metastasis, the regulatory mechanisms contributing to GC progression were analyzed, with special focuses on the roles of signaling pathways, transcription factors (TFs) and ligand-receptor pairs.

METHODS

The GSE163558 dataset was downloaded from the Gene Expression Omnibus (GEO) database to collect single-cell transcriptomic data of GC patients and their metastasis groups for cell clustering and relevant analyses. Differentially expressed genes (DEGs) in the GC and GC liver metastasis groups were screened and subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. SCENIC analysis was used to mine TFs that affected cellular subpopulations during liver metastasis from GC. The relative expression levels of TFs in GC were determined using qRT-PCR. Transwell and wound healing assays were utilized to verify the regulation of the TFs on the migration and invasion of GC cells. Interaction network between the cellular subpopulations was developed applying CellChat.

RESULTS

Single-cell clustering was performed to group six major cell subpopulations, namely, Myeloid cells, B cells, Mast cells, Epithelial cells, Fibroblasts, and TNK cells, among which the number of TNK cells was significantly increased in the GC liver metastasis group. Differentially enriched pathways of TNK cells between GC and GC liver metastasis groups mainly included IL-17 and Pi3k-Akt signaling pathways. TNK cell subsets could be further categorized into CD8 T cells, Exhausted T cells, NK cells, NKT cells, and Treg cells, with the GC liver metastasis group showing significantly more CD8 T cells and NKT cells. FOS and JUNB were the TFs of TNK cell marker genes that contributed to liver metastasis from GC and the invasion and migration of GC cell lines. Significant differences in immune cell communication ligand-receptor pairs existed between the GC and GC liver metastasis groups.

CONCLUSION

This study revealed the critical role of TNK cell subsets in GC with liver metastasis applying single-cell transcriptomics analysis. The findings provided an important theoretical basis for developing novel therapies to inhibit liver metastasis from GC.

Prediction of all-cause death and specific causes of death in patients with gastric cancer with liver metastasis: a Surveillance, Epidemiology, and End Results-based study

BACKGROUND

Gastric cancer (GC), considered the fifth most prevalent malignancy, is the fourth leading cause of cancer death worldwide. This cancer is heterogeneous and invasive and often metastasizes to the liver. The survival of patients with GC, especially cancer-specific survival (CSS), is a matter of concern to their families and medical workers in clinical practice. However, efficient tools for early risk prediction are lacking. Thus, this study aimed to develop a nomogram for forecasting the overall survival (OS) and CSS of patients with GC with liver metastasis (GCLM) based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Information on individuals with GCLM was acquired from the SEER database from January 2000 to December 2015. Patients' data were randomized into the train cohort and the test cohort. The independent factors for CSS and OS were determined by univariate and multivariate competing risk analyses and Cox proportional hazards analysis, and the nomograms for predicting CSS and OS were constructed. The receiver operating characteristic curve and calibration curve were used to measure the accuracy and calibration of nomograms.

RESULTS

Our study included 4372 patients with GCLM, with 3060 patients in the train set and 1312 in the test set. The mean follow-up period was 12.31 months. The independent factors influencing the OS of patients with GCLM were age, bone metastasis, chemotherapy, grade, lung metastasis, stage, primary site, radiotherapy, surgical primary site, T stage, and tumor size. The concordance Index (C-index) of the constructed nomogram for OS were 0.718 (SE, 0.004) in the train set and 0.0.680 (SE, 0.006) in the test set. The independent factors affecting the CSS of patients with GCLM were age, chemotherapy, grade, lung metastasis, stage, radiotherapy, regional lymph node positive, surgical primary site, and total number of tumors. The C-index for the constructed nomogram for CSS were 0.696 (SE, 0.005) in the train set and 0.696 (SE, 0.008) in the test set.

CONCLUSION

The constructed nomograms showed satisfactory performance in predicting the OS and CSS of patients with GCLM, which can help clinicians formulate follow-up and rehabilitation strategies conducive to survival. At the same time, it can provide more family and social support for high-risk groups.

Oligometastasis of Gastric Cancer: A Review

The concept of oligometastasis is not yet fully established in the field of gastric cancer. However, metastatic lesions that are localized, technically resectable at diagnosis, present a certain response to preoperative chemotherapy, and present favorable survival outcomes with local treatments, sometimes in combination with chemotherapy, are recognized as oligometastasis in the field of gastric cancer. Oligometastasis is noted in European Society for Medical Oncology guidelines and Japanese gastric cancer treatment guidelines, and local treatment is mentioned as one of the pivotal treatment options for oligometastasis. Solitary liver metastasis or a small number of liver metastases; retroperitoneal lymph node metastasis, especially localized para-aortic lymph node metastasis; localized peritoneal dissemination; and Krukenberg tumor are representative types of oligometastasis in gastric cancer. The AIO-FLOT3 trial prospectively evaluated the efficacy of multimodal treatments for gastric cancer with oligometastasis, including surgical resection of primary and metastatic lesions combined with chemotherapy, confirming favorable survival outcomes. Two phase 3 studies are ongoing to investigate the efficacy of surgical resection combined with perioperative chemotherapy compared with palliative chemotherapy. Thus far, the evidence suggests that multimodal treatment for oligometastasis of gastric cancer is promising.

Evaluating the efficacy of post-operative chemotherapy after curative resection of stage IV gastric cancer with synchronous oligo metastasis: a multicenter retrospective study

BACKGROUND

Surgical resection of oligo-metastasis in gastric cancer (GC) is weakly recommended for patients without other incurable factors in the Japanese GC Treatment Guidelines. While post-operative chemotherapy is the standard treatment in patients with stage II or III GC, its efficacy for resected stage IV GC is unclear. This study aimed to evaluate the efficacy of post-operative chemotherapy after curative resection of GC with oligo-metastasis.

METHODS

We retrospectively reviewed the medical records of patients with GC who were diagnosed with synchronous oligo-metastasis at 20 institutions in Japan between 2007 and 2012. The selection criteria were: adenocarcinoma, stage IV with oligo-metastasis at liver or lymph node without other distant metastasis, curative resection including synchronous oligo-metastasis, and no prior treatment of GC before surgery.

RESULTS

A total of 110 patients were collected. Of the 94 eligible patients, 84 underwent gastrectomy with surgical resection of oligo-metastasis (39 [41%] liver metastasis and 55, [59%] distant lymph node metastasis), followed by post-operative chemotherapy with S-1 (S1: n = 55), S1 plus cisplatin (CS: n = 22), or Others (n = 7). Moreover, 10 patients did not receive post-operative chemotherapy (Non-Cx). The median overall survival (OS) was 35.2 and 11.1 months in the post-operative chemotherapy and Non-Cx groups (hazard ratio, 3.56; 95% confidence interval, 1.74-7.30; p < 0.001), respectively. In multivariable analysis, Non-Cx and age over 70 years were identified as poor prognostic factors for OS (p < 0.05).

CONCLUSIONS

Curative resection followed by post-operative chemotherapy in patients with GC with synchronous oligo-metastasis showed favorable survival.

Survival Outcomes of Hepatectomy in Gastric Cancer Liver Metastasis: A Systematic Review and Meta-Analysis

Gastric cancer liver metastasis (GCLM) is a contraindication for surgical treatment in current guidelines. However, the results of recent studies are questioning this paradigm. We assessed survival outcomes and their predictors following hepatectomy for GCLM in a systematic review of studies published from 2000 to 2022 according to PRISMA guidelines. We identified 42,160 references in four databases. Of these, 55 articles providing data from 1990 patients fulfilled our criteria and were included. We performed a meta-analysis using random-effects models to assess overall survival (OS) and disease-free survival (DFS) at one, three, and five years post-surgery. We studied the impact of potential prognostic factors on survival outcomes via meta-regression. One, three, and five years after surgery, OS was 69.79%, 34.79%, and 24.68%, whereas DFS was 41.39%, 23.23%, and 20.18%, respectively. Metachronous presentation, well-to-moderate differentiation, small hepatic tumoral size, early nodal stage, R0 resection, unilobar compromisation, and solitary lesions were associated with higher overall survival. Metachronous presentation, smaller primary tumoral size, and solitary metastasis were linked to longer DFS. The results of our meta-analysis suggest that hepatectomy leads to favorable survival outcomes in patients with GCLM and provides data that might help select patients who will benefit most from surgical treatment.

Will Patients With Liver Metastasis From Aggressives Cancers Benefit From Surgical Resection?

Background

We aimed to evaluate the outcomes of resections for liver metastases (LMs) originating from pancreatic ductal adenocarcinoma (PDAC), non-small cell lung cancer (NSCLC), and esophagus/gastric cancers (EGCs), which we label as major killers (MKs; overall survival (OS) under 10%). We hypothesized that LM resection must provide the patient with almost a year of OS postoperatively that is considered beneficial.

Methods

From January 2005 to December 2020, 23 patients underwent resection for isolated LM from MKs. These patients underwent surgery after a multidisciplinary discussion about their performance status, disease evolution during prolonged medical treatment, and the existence or absence of extrahepatic metastases.

Results

LM originated from an PDAC, EGC, or NSCLC in 10 patients (43%), nine patients (39%), and four patients (18%), respectively. The median delay between primary cancer and LM diagnoses was 12 months, and the median delay between LM diagnosis and liver resection was 10 months. Most patients, who had objectively responded to medical treatment (57%), had a solitary (61%) and unilobar (70%) LM. Severe morbidity and 90-day mortality rates were 13% and 4.3%, respectively. Margin-free resection was achieved in 16 patients (70%). After liver resection, the median OS was 24 months without a statistical difference when considering the primary tumor site; 1, 3-, and 5-year OS were 70%, 23%, and 23%, respectively.

Conclusion

Selection based on criteria such as good clinical condition, response to treatment, and long observation period helped identify patients with LM of MKs who seemed to benefit from resection.

Development and validation of two nomograms for predicting overall survival and cancer-specific survival in gastric cancer patients with liver metastases: A retrospective cohort study from SEER database

BACKGROUND

Gastric cancer is heterogeneous and aggressive, especially with liver metastasis. This study aims to develop two nomograms to predict the overall survival (OS) and cancer-specific survival (CSS) of gastric cancer with liver metastasis (GCLM) patients.

METHODS

From January 2000 to December 2018, a total of 1936 GCLM patients were selected from the Surveillance, Epidemiology, and End Results Program (SEER) database. They were further divided into a training cohort and a validation cohort, with the OS and CSS serving as the study's endpoints. The correlation analyses were used to determine the relationship between the variables. The univariate and multivariate Cox analyses were used to confirm the independent prognostic factors. To discriminate and calibrate the nomogram, calibration curves and the area under the time-dependent receiver operating characteristic curve (time-dependent AUC) were used. DCA curves were used to examine the accuracy and clinical benefits. The clinical utility of the nomogram and the AJCC Stage System was compared using net reclassification improvement (NRI) and integrated differentiation improvement (IDI) (IDI). Finally, the nomogram and the AJCC Stage System risk stratifications were compared.

RESULTS

There was no collinearity among the variables that were screened. The results of multivariate Cox regression analysis showed that six variables (bone metastasis, lung metastasis, surgery, chemotherapy, grade, age) and five variables (lung metastasis, surgery, chemotherapy, grade, N stage) were identified to establish the nomogram for OS and CSS, respectively. The calibration curves, time-dependent AUC curves, and DCA revealed that both nomograms had pleasant predictive power. Furthermore, NRI and IDI confirmed that the nomogram outperformed the AJCC Stage System.

CONCLUSION

Both nomograms had satisfactory accuracy and were validated to assist clinicians in evaluating the prognosis of GCLM patients.

Surgery is Associated With Improved Overall Survival in Patients With Metastatic Gastric Cancer: A National Cancer Database Analysis

BACKGROUND

The 5-year overall survival (OS) rate for patients with metastatic gastric cancer (mGC) is 5.3%. Surgery for mGC is controversial.

METHODS

We identified all mGC patients who received chemotherapy using the National Cancer Database (2004-2015). Patients were grouped according to surgery of: (1) the primary site (PS) only, (2) primary and distant sites (PDS), (3) distant site only (DS), or (4) no surgery (NS). A propensity score adjustment and multivariate regression was used to compare OS.

RESULTS

Overall, 18,772 patients met the inclusion criteria: (1) PS (n = 962, 5.1%), (2) PDS (n = 380, 2.1%), (3) DS (n = 984, 5.2%), and 16,446 NS (87.6%). Surgery was associated with improved OS in the PS and PDS groups (hazard ratios: .489 (95% CI: .376-.636); .583 (95% CI: .420-.811), P < .001) (median OS 15.8 and 15.9 months vs 8.6 for NS patients, respectively).

CONCLUSIONS

Gastrectomy with or without metastasectomy is associated with improved survival in stage IV gastric cancer patients receiving chemotherapy. This warrants further prospective studies.

A grading system for predicting the prognosis of gastric cancer with liver metastasis

OBJECTIVE

The prognosis of patients with liver metastases from gastric cancer is determined using tumor size and number of metastases; this is similar to the factors used for the prediction of liver metastases from colorectal cancer. The relationship between the degree of liver metastasis from gastric cancer and prognosis with reference to the classification of liver metastasis from colorectal cancer was investigated.

METHODS

This was a multi-institutional historical cohort study. Among patients with stage IV gastric cancer, who visited the cancer hospitals in Fukushima Prefecture, Japan, between 2008 and 2015, those with simultaneous liver metastasis were included. Abdominal pretreatment computed tomography images were reviewed and classified into H1 (four or less liver metastases with a maximum diameter of ≤5 cm); H2 (other than H1 and H3) or H3 (five or more liver metastases with a maximum diameter of ≥5 cm). The hazard ratio for overall survival according to the H grade (H1, H2 and H3) was calculated using the Cox proportional hazards model.

RESULTS

A total of 412 patients were analyzed. Patients with H1, H2 and H3 grades were 118, 162 and 141, respectively, and their median survival time was 10.2, 5.7 and 3.1 months, respectively (log-rank P < 0.001). The adjusted hazard ratio for overall survival was H1: H2: H3 = reference: 1.39 (95% confidence interval: 1.04-1.85): 1.69 (95% confidence interval: 1.27-2.27).

CONCLUSIONS

The grading system proposed in this study was a simple and easy-to-use prognosis prediction index for patients with liver metastasis from gastric cancer.

Ex vivo liver resection followed by autotransplantation in radical resection of gastric cancer liver metastases: A case report

BACKGROUND

Radical resection of gastric cancer liver metastases (GCLM) can increase the 5-year survival rate of GCLM patients. However, patients may lose the theoretical feasibility of surgery due to the critical location of liver metastasis in some cases.

CASE SUMMARY

A 29-year-old woman had a chief complaint of chronic abdominal pain for 1 year. Abdominal computed tomography and magnetic resonance imaging examinations suggested a mass of unknown pathological nature located between the first and second hila and the margin of the lower segment of the right lobe of the liver. The anterior wall of the gastric antrum was unevenly thickened. The diagnosis of (gastric antrum) intramucosal well-differentiated adenocarcinoma was histopathologically confirmed by puncture biopsy with gastroscopy guidance. She underwent radical resection (excision of both gastric tumors and ex vivo liver resection followed by autotransplantation simultaneously) followed by XELOX adjuvant chemotherapy. Without serious postoperative complications, the patient was successfully discharged on the 20^th day after the operation. Pathological examination of the excised specimen indicated that gastrectomy with D2 lymph node dissection for primary gastric tumors and R0 resection for liver metastases were achieved. The resected mass was confirmed to be poorly differentiated gastric carcinoma (hepatoid adenocarcinoma with neuroendocrine differentiation) with liver metastases in segments VIII. No recurrence or metastasis within the liver was found during a 7.5-year follow-up review that began 1 mo after surgery.

CONCLUSION

Application of ex vivo liver resection followed by autotransplantation in radical resection for GCLM can help selected patients with intrahepatic metastases located in complex sites obtain a favorable clinical outcome.

The therapeutic strategy for advanced gastric cancer with pyloric stenosis and liver metastasis; successfully treated by gastro-jejunal bypass and chemotherapy first, followed by curative R0 resection

BACKGROUND

The indication of surgical resection for liver metastasis from gastric cancer (GC) is still limited and controversial because of its more aggressive oncological characteristics than liver metastasis from colorectal cancer. Pyloric stenosis causes an inadequate oral intake and malnutrition in GC patients. We herein report a case of GC with these two factors that was successfully treated by the combination of gastro-jejunal bypass and chemotherapy, followed by curative R0 resection.

CASE PRESENTATION

A 60-year-old man was diagnosed with type 2 GC with liver metastasis and pyloric stenosis, which was confirmed as the HER2-positive type. He underwent gastrojejunostomy and received capecitabine and cisplatin (XP) + trastuzumab chemotherapy. After three courses of the XP + trastuzumab regimen, shrinkage of the primary lesion and liver metastasis was confirmed and his nutritional parameters markedly improved with a stable oral intake after bypass surgery. He underwent curative R0 resection by distal gastrectomy with D2 lymphadenectomy and partial hepatectomy. Histologically, viable tumor cells were observed in less than one-third of the primary lesion, and only scar tissue without viable cancer cells was noted in the resected liver specimen. His postoperative course was uneventful, and recurrence has not been detected in the 30 months after surgery without adjuvant chemotherapy.

CONCLUSION

The present case report describes a successful strategy for advanced GC with pyloric stenosis and liver metastasis.

Is There a Role for Locoregional Therapies for Non-colorectal Gastrointestinal Malignancies?

The liver is the most common site of metastases from solid gastrointestinal tract tumors. Over the past few decades, the role of locoregional therapies, resection and thermal ablation, for neuroendocrine and colorectal liver metastases has been widely studied. However, for liver metastases originating from other gastrointestinal organs, the role of locoregional treatment remains unclear. This review summarizes and discusses the available evidence regarding benefits, risks, and indications for locoregional therapies for non-colorectal and non-neuroendocrine gastrointestinal liver metastases, highlighting the importance of multidisciplinary approach and patient selection.

Chinese consensus on the diagnosis and treatment of gastric cancer with liver metastases

Background

The incidence of gastric cancer with liver metastases (GCLM) is 9.9-18.7%, with a median survival time of 11 months and a 5-year survival rate <20%. Multidisciplinary treatment (MDT) is gradually gaining recognition as the most important method. However, specific treatment plans remain unclear. The aim of study was to provide a consensus to improve the diagnosis and treatment of GCLM.

Methods

We brought together experts from relevant medical fields across China, including the Chinese Research Hospital Association Digestive Tumor Committee, Chinese Association of Upper Gastrointestinal Surgeons, Chinese Gastric Cancer Association, and the Gastrointestinal Surgical Group of Chinese Surgical Society Affiliated to Chinese Medical Association, to discuss and formulate this consensus.

Results

A consensus was reached on the diagnosis and treatment of GCLM. Moreover, we have developed a new clinical classification system, the Chinese Type for Gastric Cancer Liver Metastases, based on the likelihood of a surgical treatment being successful.

Conclusions

The MDT mode should be implemented throughout all treatment of GCLM.A Chinese version of this expert consensus has been published in the Chinese Journal of Practical Surgery (Volume 39, Issue 10, p. 405-411). Written permission was obtained from the Chinese Journal of Practical Surgery to disseminate the expert consensus in English.

Intestinal-type histology is associated with better prognosis in patients undergoing liver resection for gastric/esophagogastric-junction liver metastasis

The indication for resection of gastric/esophagogastric-junction liver metastasis (GELM) has yet to be established. This study aimed to investigate prognostic factors in patients undergoing GELM resection. From 2001 to 2015, 31 consecutive patients underwent resection for GELM; and factors for poor prognosis were evaluated. Of the 31 patients, 23 (74.2%) developed multiple liver metastases. The histology of gastric cancer was intestinal-type adenocarcinoma in 21 patients (67.7%). Median overall survival (OS) was 3.2 years. The 1-, 3-, and 5-year OS rates were 92.8%, 56.2%, and 42.2%, respectively. The 1-, 3-, and 5-year recurrence-free survival (RFS) rates were 58.5%, 31.3%, and 31.3%, respectively. Multivariate analysis indicated that intestinal-type adenocarcinoma was associated with a significantly lower risk of OS (hazard ratio [HR], 0.26; p =0.022) and RFS (HR, 0.25; p = 0.008). In multiple logistic regression analysis, intestinal-type adenocarcinoma (odds ratio, 0.14; p = 0.012) reduced incidence of extra-hepatic recurrence after GELM resection. In conclusion, GELM resection in patients with intestinal-type histology is preferable because intestinal-type adenocarcinoma is associated with better prognosis and a lower incidence of extra-hepatic recurrence than diffuse/other-type adenocarcinoma.

Surgical management of metastatic gastric cancer: moving beyond the guidelines

Despite decreasing incidence, gastric cancer remains a major health problem worldwide and is associated with poor survival. The poor survival is mainly attributed to delayed presentation which may cause local or systemic metastases. The standard of care for patients with metastatic gastric cancer (MGC) is palliative chemotherapy with best supportive care. Although the survival has improved owing to advances in chemotherapeutic agents, it is still unsatisfactory, and some perspective changes are needed in the management of MGC to improve the outcomes. Therefore, various alternative treatment strategies for MGC have formed the most important research topics. Liver-directed treatment (LDT) options such as liver resection, radiofrequency ablation (RFA), microwave ablation (MWA), and hepatic artery infusion chemotherapy (HAIC) have been studied in the management of liver metastasis from gastric cancer (LMGC). Intraperitoneal chemotherapy (IPC) in addition to cytoreductive surgery (CRS) aiming to remove all macroscopic tumor focus resulting from peritoneal dissemination is the treatment option for peritoneal metastasis, while para-aortic lymph node dissection is the treatment option for para-aortic lymph node metastasis which is considered to be M1 disease. Conversion surgery is a novel concept aiming at R0 resection for originally unresectable or marginally resectable tumors after a remarkably good response to the chemotherapy. Large amounts of data in the literature have demonstrated the benefits of individualized approaches such as the combination of systemic and local treatment options in selected patient groups. In this review, we aimed to explore the current and future treatment options by reviewing the literature on this controversial topic.

Surgery or Locoregional Approaches for Hepatic Oligometastatic Pancreatic Cancer: Myth, Hope, or Reality?

Despite extensive research, pancreatic ductal adenocarcinoma (PDAC) remains a difficult-to-treat cancer associated with poor survival. Due to the known aggressive disease biology, palliative chemotherapy is the only routinely recommended treatment in the metastatic setting in patients with adequate performance status. However, in a subset of patients with oligometastatic disease, multimodality treatment with surgery and/or locoregional approaches may provide long-term disease control and prolong survival. In fact, in highly selected cases, median overall survival has been reported to extend to 56 months in patients treated with surgery. In particular, liver and extraregional nodal resections may provide long-term tumor control with acceptable morbidity. Current guidelines do not recommend surgery for patients with metastatic PDAC and, in the case of PDAC with oligometastases, there are no published randomized controlled trials regarding locoregional or surgical approaches. Here we review the literature on surgical and locoregional approaches including radiofrequency ablation, irreversible electroporation, and stereotactic body radiation, and focus on patients with hepatic oligometastatic pancreatic cancer. We provide a summary regarding survival outcomes, morbidity and mortality and discuss selection criteria that may be useful to predict the best outcomes for such strategies.

Oligometastatic gastric cancer: An emerging clinical entity with distinct therapeutic implications

Gastric cancer (GC) remains responsible for a high burden worldwide being the third leading cause of cancer-related mortality. Most of patients present at an advanced stage at diagnosis and are thus candidates to standard chemotherapy resulting in median survival of less than 1 year. Oligometastatic gastric cancer is an increasingly recognized clinical entity characterized by limited metastatic spread that has been showing to benefit from aggressive multimodality strategies encompassing chemotherapy and surgery. The ongoing RENAISSANCE/AIO-FLOT5 (NCT02578368) phase III trial is aimed at evaluating if perioperative chemotherapy with FLOT in combination with surgical resection of the primary tumour and metastases could become the new standard of care for oligometastatic GC. In the meantime, in addition to currently available clinical parameters, the emerging predictive/prognostic role of biomarkers such mismatch repair deficiency/microsatellite instability high status needs to be specifically addressed also in this subgroup of GC to assist in patient selection.

The Chinese Society of Clinical Oncology (CSCO): clinical guidelines for the diagnosis and treatment of gastric cancer

China is one of the countries with the highest incidence of gastric cancer. There are differences in epidemiological characteristics, clinicopathological features, tumor biological characteristics, treatment patterns, and drug selection between gastric cancer patients from the Eastern and Western countries. Non-Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer patients. The Chinese Society of Clinical Oncology (CSCO) arranged for a panel of senior experts specializing in all sub-specialties of gastric cancer to compile, discuss, and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence-based medicine in China and abroad. By referring to the opinions of industry experts, taking into account of regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted experts' consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes. This guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis, comprehensive treatment, and follow-up visits for gastric cancer.

The survival benefit of palliative gastrectomy and/or metastasectomy in gastric cancer patients with synchronous metastasis: a population-based study using propensity score matching and coarsened exact matching

Introduction: Palliative surgeries were controversial for asymptomatic metastatic gastric cancer (mGC) patients. This study was aimed to evaluate survival benefit of palliative surgeries to gastric and/or metastatic tumors in mGC patients based on U.S population.

Materials and Methods: A total of 8345 gastric cancer patients diagnosed with synchronous distal metastasis between 2004 to 2013 from the Surveillance, Epidemiology, and End Results Program (SEER) database were divided into four groups according to surgery strategies: surgeries to both primary and metastatic tumors (SPM), gastrectomy only (GO), metastasectomy only (MO) and no surgery performed (NS). Their clinicopathological characteristics and overall survival (OS) were analyzed before and after propensity score matching (PSM) and coarsened exact matching (CEM).

Results: The median OS of SPM and GO patients was both significantly higher than NS patients (11 months vs. 8 months vs. 5 months; P<0.001, respectively) while that of MO was not (6 months vs. 5 months; P= 0.286). In comparisons between surgery strategies, survival benefit was similar between SPM and GO groups (P=0.389) and both showed significantly better survival than MO patients (P<0.001). All surgery strategies were proved to be favorable prognostic factors over non-surgical treatment (Hazard ratio (HR) for SPM: 0.60, P<0.001; HR for GO: 0.62, P<0.001; HR for MO: 0.91, P=0.046). Similar results were obtained after matching by PSM and CEM except that prognostic impact of MO deteriorated.

Conclusions: Gastrectomy plus metastasectomy or gastrectomy alone could be adopted as a choice of improving survival in the U.S population. Metastasectomy alone is not generally recommended.

Small hepatocellular carcinoma suppressed by chemotherapy for synchronous gastric carcinoma after laparoscopy-assisted radical distal gastrectomy: A case report and literature review

RATIONALE

Synchronous gastric carcinoma and hepatocellular carcinoma (HCC) is rare. It is hard to distinguish synchronous HCC from metastatic liver cancer in this condition. The treatment and prognosis is quite different for synchronous HCC of gastric carcinoma and liver metastasis of gastric carcinoma.

PATIENT CONCERNS

A 68-year-old man with a chief complaint of epigastric pain for 1 year, accompanied by reflux and belching. The patient was diagnosed with gastric carcinoma (cT4NxM0) and laparoscopy-assisted radical distal gastrectomy was performed. This was followed by chemotherapy of FOLFOX regimen. However, a liver nodule growth was observed after postoperative systemic treatment.

DIAGNOSIS

The initial diagnosis was liver metastasis of gastric carcinoma. However after hepatectomy of segment VI and VII as well as thrombectomy of right hepatic vein, histology revealed intermediate to poor differentiated HCC. Hence this case was diagnosed as synchronous gastric carcinoma and HCC.

INTERVENTIONS

A preventive transcatheter arterial chemoembolization (TACE) was conducted at 4 weeks after hepatectomy. Another FOLFOX regimen was suggested, but was refused by the patient.

OUTCOMES

The patient survived without tumor recurrence for 9 months after the second surgery.

LESSONS

Synchronous HCC should be routinely distinguished from gastric carcinoma liver metastasis, especially for patients with hepatitis B virus (HBV) infection. The FOLFOX4 regimen for treating gastric carcinoma liver metastasis may have inhibited the progression of primary HCC in this case. This patient with HCC benefited from liver resection, inspite of hepatic vein tumor thrombosis.

Outcomes of 1,639 hepatectomies for non-colorectal non-neuroendocrine liver metastases: a multicenter analysis

BACKGROUND

Whether non-colorectal non-neuroendocrine liver metastasis (NCNNLM) should be treated surgically remains unclear.

METHODS

Data regarding 1,639 hepatectomies performed between 2001 and 2010 for 1,539 patients with NCNNLM were collected from 124 institutions. Patient characteristics, types of primary tumor, characteristics of liver metastases, and post-hepatectomy outcomes were analyzed.

RESULTS

The five most frequent primary tumors were gastric carcinoma (540 patients [35%]), gastrointestinal stromal tumor (204 patients [13%]), biliary carcinoma (150 patients [10%]), ovarian cancer (107 patients [7%]), and pancreatic carcinoma (77 patients [5%]). R0/1 hepatectomy was achieved in 90% of patients, with 1.5% in-hospital mortality rate. Overall and disease-free survival rates of 1,465 patients included in survival analysis were 41% and 21%, respectively, at 5 years, and 28% and 15%, respectively, at 10 years. Five-year survival associated with the five frequent primary tumors were 32%, 72%, 17%, 52%, and 31%, respectively, and factors predictive of a poor outcome differed by the primary tumor type.

CONCLUSIONS

Our data indicated that hepatectomy is safe for NCNNLM and that patient prognoses vary depending on the type of primary tumors. Indications for hepatectomy should be determined with reference to survival rates and risk factors specific to each of the various types of primary tumor.

Current challenges in gastric cancer surgery: European perspective

Gastric cancer (GC) remains one of the most common causes of cancer death worldwide with expected 5-year survival rates around 25% in Western countries. In order to improve treatment strategy, a most effective staging process should be completed. A novel TNM staging for GC has been proposed recently, along with a separate staging system for GC patients who underwent preoperative therapy (ypStage). Availability of high-quality imaging and access to diagnostic laparoscopy with lavage cytology should be applied while planning the multimodal therapy. In the European setting, GC treatment is based on a combination of surgery and perioperative chemotherapy. However, in selected groups of patients with high risk of locoregional recurrence, adjuvant chemoradiotherapy should be considered. New epidemiological trends of GC in the Western countries include an upward shift in the location of the primary tumour and a relative increase of advanced and diffuse type tumours. These trends dictate modification of surgical techniques towards a more individualized GC treatment approach.

Distinct molecular subtypes of gastric cancer: from Laurén to molecular pathology

In Western countries the majority of gastric cancers (GC) are usually diagnosed in advanced stages reporting a 5-year survival rate of only 26%. The Laurén classification of GC was most widely used in clinical practice since it reflects GC morphology, epidemiology, tumor biology, clinical management and outcome. Despite the initial promise of individualizing antitumor treatment, the management of GC still remains relatively broad and general. Apart from clinical staging, molecular profiling enables targeting of the identified underlying alterations, rather than histology. In contrast to breast carcinoma, molecular classification of GC does not yet imply treatment modality. Molecular classifications of GC and their therapeutic implications are therefore extensively studied. The current proposed molecular divisions of GC come from three different parts of the world where different standard treatment modalities for advanced GC are recommended. Wider use of GC molecular subtyping may solve problems, such as susceptibility to novel systemic therapy regimens or selection of patients for aggressive surgery and targeted adjuvant/conversion therapy. In any case, the rapid entry of novel molecular targeted therapies into routine oncology practice clearly underscores the urgent need for clinicians to be aware of these new possibilities.

[Resection of advanced esophagogastric adenocarcinoma : Extended indications]

In the current German S3 guidelines surgical treatment is not recommended for metastatic gastric cancer or metastatic adenocarcinoma of the esophagogastric junction; however, in routine practice the indications can be extended so that there may be occasions in which radical surgical intervention for specific individuals may be appropriate as part of a multimodal therapy with curative intent. This article presents the scientific rationale of such an approach based on the available literature considering modern, multimodal therapy concepts including criteria to be met for radical surgery. Currently only retrospective trials and limited current meta-analysis data are available for justifying surgical treatment for metastatic adenocarcinoma. The recently published initial results of the FLOT-3 study identified a patient subgroup that benefits from a resection even though metastasis has occurred. Whether surgical therapy will become an integral part of the treatment of limited metastatic adenocarcinoma of the stomach and esophagus in the future, has to be demonstrated by large prospective randomized studies, such as the RENAISSANCE/FLOT-5 study.

Intensified neoadjuvant multimodal approach in synchronous liver metastases from gastric cancer: a single institutional experience

BACKGROUND

Synchronous liver metastases (LM) from gastric (GC) or esophagogastric junction (EGJ) adenocarcinoma are a rare events. Several trials have evaluated the role of liver surgery in this setting, but the impact of preoperative therapy remains undetermined.

METHODS

Patients with synchronous LM from GC/EGJ adenocarcinoma who achieved disease control after induction chemotherapy (ICT) and were subsequently scheduled to chemoradiotherapy (CRT) to the primary tumor and surgery assessment were retrospectively analyzed. Pathological response, patterns of relapse, progression-free survival (PFS), and overall survival (OS) were calculated. From July 2002 to September 2012, 16 patients fulfilling the inclusion criteria were identified.

RESULTS

Primary tumor site was GC (nine patients) or EGJ (seven patients). LM were considered technically unresectable in nine patients. Radiological response to the whole neoadjuvant program was achieved in 13 patients. Eight patients underwent surgical resection of the primary tumor; in five of these LM were resected. A complete pathological response in the primary or in the LM was found in four and three patients, respectively. The most frequent site of relapse/progression was systemic (eight patients). Local and liver-only relapses were observed in two patients each. After a median follow-up of 91 months, the median OS and PFS were 23.0 (95% CI 13.2-32.8) and 17.0 months (95% CI 11.7-22.3). 5-year actuarial PFS is 17.6%.

CONCLUSION

Our results suggest that an intensified approach using ICT followed by CRT in synchronous LM from GC/EGJ adenocarcinoma is feasible and may translate into prolonged survival times in selected patients.

Liver metastases from gastric carcinoma: A Case report and review of the literature

Gastric carcinoma (GC) is the fifth most common malignancy worldwide but the third leading cause of cancer death, and surgery remains the only curative treatment option. Prognosis of patients with liver metastases from gastric carcinoma (LMGC) is poor, and the optimal treatment of metastatic gastric cancer remains a matter of debate. In 2002, a 53-year-old male patient with GC and synchronous oligometastatic lesion in liver VIII segment underwent a total gastrectomy combined with metastasectomy. The pathologic diagnosis was stage IV gastric adenocarcinoma (pT3N2M1), which was treated with adjuvant chemotherapy (cisplatin, epirubicin, leucovorin, and 5-fluorouracil). In 2012, abdominal ultrasound and percutaneous liver biopsy revealed recurrence of the metastasis in the right liver lobe. Progression of the disease was observed after palliative chemotherapy (epirubicin, oxaliplatin, and capecitabine). Nevertheless, an extended right hemihepatectomy, with excision of segments 1, 4A, 5, 6, 7, and 8, was still performed. Pathologic examination confirmed large KRAS- and HER2-negative LMGC. The patient is alive and free of disease 47 months after the repeated hepatectomy and 13 years after removal of the primary GC and synchronous liver metastasis. Based on review of 27 articles, 5-year overall survival rate following gastrectomy and liver metastasectomy may reach 60%, with median survival time up to 74 months. Although the combination of aggressive surgical approach with systemic therapy for LMGC is controversial, it may allow favorable outcome. Careful selection of patients based on evaluable predictive factors for R0 surgical resection of both primary tumor and liver metastases can lead to cure, as shown in our case presentation, where a 10-year relapse-free survival was observed, followed by successful repeated hepatectomy due to liver metastases.

Surgical resection for hepatic metastasis from gastric cancer: a multi- institution study

Background

The beneficial effect of surgical resection for hepatic metastasis from gastric cancer (HMGC) remains elusive. This study was conducted to analyze surgical outcomes of HMGC and determine the prognostic factors associated with survival.

Results

The in-hospital mortality rate was zero, and the overall morbidity rate was 56%. The overall 1-, 3-, and 5-year survival rate after surgery was 87.5%, 47.6%, and 21.7%, respectively, with a median survival time of 34.0 months. Multiple liver metastases (hazard ratio [HR] =1.998; 95% confidence interval [CI] = 1.248-3.198; P = 0.004) and ≥ T3 stage of the primary gastric cancer (HR = 2.065; 95% CI = 1.201–3.549; P = 0.009) were independent prognostic determinants in the multivariate analysis.

Materials and Methods

Data on surgical resection of 96 patients with HMGC at six institutions in China were analysed retrospectively. Prognostic factors were assessed by multiple stepwise regression analysis using the Cox model.

Conclusions

Surgical resection for HMGC is feasible and beneficial to long-term survival in selected patients.

Oligometastatic Disease in Upper Gastrointestinal Cancer - How to Proceed?

BACKGROUND

In the present study we review and discuss the current evidence and suggest how to proceed in the management of oligometastatic disease in upper gastrointestinal cancer.

METHODS

An electronic search of the PubMed database for relevant articles was performed.

RESULTS

Both the search for 'oligometastasis', 'oligometastases', 'oligometastatic', 'oligometastatic disease' as well as 'esophageal' and 'esophageal cancer' and the search for 'oligometastasis', 'oligometastases', 'oligometastatic', 'oligometastatic disease' as well as 'gastric', 'gastric cancer', 'stomach', and 'stomach cancer' yielded very few studies. Most data need to be extrapolated in general studies on oligometastatic diseases of different origins. No randomized controlled trial could be found.

CONCLUSION

In the absence of data to formulate recommendations on how to proceed in the treatment of oligometastatic disease in upper gastrointestinal cancer, a more aggressive treatment of oligometastatic disease can be considered in patients whose tumors show a more favorable neoplastic behavior after the 'test of time'. The RENAISSANCE study will certainly deliver important data regarding this aspect.

Proliferation and motility of hepatocellular, pancreatic and gastric cancer cells grown in a medium without glucose and arginine, but with galactose and ornithine

Human primary hepatocytes are able to survive in a medium without glucose and arginine, but supplemented with galactose and ornithine (hepatocyte selection medium; HSM). To address the possibility of the application of HSM in cancer therapy, hepatocellular carcinoma cells, pancreatic cancer cells and gastric cancer cells were cultured in HSM. Cell proliferation was analyzed using an MTS assay. Morphological changes were analyzed using hematoxylin and eosin staining. Apoptosis was analyzed using a TUNEL assay and cell motility was assessed with a scratch assay. Cell proliferation was significantly suppressed in cell lines grown in HSM (P<0.01 in all the cell lines). Hematoxylin and eosin staining revealed pyknotic nuclei, suggesting that these cells had undergone apoptosis. The number of TUNEL-positive cells was significantly increased in HSM. In the scratch assay, the distance between the growing edge and the scratched edge was significantly lower (P<0.01 in all the cell lines) in cells cultured in HSM, compared with those grown in Dulbecco's modified Eagle's medium or RPMI-1640. Therefore, the proliferation and motility of hepatocellular carcinoma cells, pancreatic cancer cells and gastric cancer cells was suppressed, and these cells subsequently underwent apoptosis in a medium without glucose and arginine, but containing galactose and ornithine.

Surveillance for Gastric Cancer

This article discusses the current National Comprehensive Cancer Network guidelines and other available Western and Eastern guidelines for the surveillance of gastric cancer following surgical resection. It reviews the literature assessing the utility of intensive surveillance strategies for gastric cancer, which fails to show an improvement in survival. The unique issues relating to follow-up of early gastric cancer and after endoscopic resection of early gastric cancer are discussed. This article also reviews the available modalities for follow-up. In addition, it briefly discusses the advancements in treatment of recurrent and metastatic disease and the implications for gastric cancer survival and surveillance strategies.

Hepatectomy for liver metastases from gastric cancer: a systematic review

BACKGROUND

Official guidelines recommend palliative treatments for patients with liver metastases from gastric cancer. However, many case series reported that hepatectomy for such cases is safe and effective. This systematic review compares the overall survival between hepatectomy and palliative therapy in patients with liver metastases from gastric cancer.

METHODS

Two independent reviewers performed a systematic search of literature in EMBASE and PubMed, updated until 26 October 2016. The Newcastle-Ottawa score for cohort studies was used for quality assessment of included studies.

RESULTS

A total of eight cohort studies involving 196 patients in the hepatectomy arm and 481 in the palliative arm were included. Median overall survival of patients in the two arms was 23.7 (range, 13.0 to 48.0) and 7.6 (range, 5.5 to 15.2), respectively. Median rates of overall survival of the two arms were 69, 40, 33 and 27, 8, 4% at 1, 2, and 3 years, respectively. Comparing with palliative therapy, hepatectomy was associated with significantly lower mortality at 1 year (odds ratio 0.17, P < 0.001) and 2 years (odds ratio 0.15, P < 0.001). Among the patients who underwent hepatectomy, Asian cohorts showed higher median rates of overall survival than Western cohorts at 1 year (76 vs. 60%), 2 years (47 vs. 30%) and 3 years (39 vs. 23%).

CONCLUSIONS

Hepatectomy in the management of liver metastases from gastric cancer can be considered effective. In the elective setting, hepatectomy provides a potential alternative to palliative therapy.

Surgical treatment of gastric cancer liver metastasis: Focus on controversy

Gastric cancer is the third most common malignancy in China, and the liver is the most common metastasis site which is responsible for poor prognosis in advanced gastric cancer. Gastric cancer liver metastasis (GCLM) has long been regarded as a systemic disease, and chemotherapy is still the main treatment, although the efficacy is unsatisfying. Recently, active surgical resection is reported to be practicable and beneficial in highly selected cases. In addition, either radiofrequency ablation or hepatic arterial infusion can be used for unresectable locally advanced tumors. Management of liver metastasis is the key to significantly improve the prognosis of patients. Further research is needed to establish individualized modalities for these particular patients. We herein discuss the surgical treatment of GCLM.

Resection of Large Metachronous Liver Metastasis with Gastric Origin: Case Report and Review of the Literature

INTRODUCTION

Increasing evidence suggests that surgical resection may be offered to a subgroup of patients with liver metastasis of gastric adenocarcinoma. The aim of this case report is to illustrate the surgical resection of a single liver metachronous recurrence twelve months after a radical total gastrectomy for cancer.

CASE REPORT

A 63-year-old male patient with an Eastern Cooperative Oncology Group performance status of 1 was referred to our hospital for a single, large liver metastasis, twelve months after a radical total gastrectomy and DII lymphadenectomy for upper third gastric adenocarcinoma. As the adjuvant treatment, the patient received 12 cycles of FOLFOX chemotherapy. During the present admission, the abdominal computed tomography (CT) revealed a single liver metastasis located in the segments 5 and 6, of 105/85 mm in diameter. Surgical resection by an open approach of liver metastasis was decided. We performed a non-anatomical liver resection, without inflow control due to significant peritoneal adhesions in the liver hilum secondary to the previous lymphadenectomy. The patient was discharged after seven days, with an uneventful recovery. Six months after the second surgical procedure, the patient developed a local liver recurrence. The surgical resection of the liver recurrence was performed, with no postoperative morbidities, and the patient was discharged after eight days. Three months after the latest surgery, the patient is under adjuvant chemotherapy, with no imagistic signs of further recurrences.

CONCLUSIONS

  Hepatic resection for liver metastasis of gastric origin may offer satisfactory oncological outcomes in a very selected subgroup of patients.

Prognostic Value of Lymph Node Ratio in Patients Receiving Combined Surgical Resection for Gastric Cancer Liver Metastasis: Results from Two National Centers in China

The purpose of this study was to evaluate the prognostic value of lymph node ratio (LNR) in patients with gastric cancer liver metastasis (GCLM) who received combined surgical resection. A retrospective analysis of 46 patients from two hospitals was conducted. Patients were dichotomized into two groups (high LNR and low LNR) by the median value of LNR. The overall survival (OS) and recurrence-free survival (RFS) were analyzed by the Kaplan-Meier method with the log-rank test. The Cox proportional hazard model was used to carry out the subsequent multivariate analyses. And the relationship between LNR and clinicopathological characteristics was assessed. The cut-off value defining elevated LNR was 0.347. With a median follow-up of 67.5 months, the median OS and RFS of the patients were 17 and 9.5 months, respectively. Six patients survived for >5 years after surgery. Patients with higher LNR had significantly shorter OS and RFS than those with lower LNR. In the multivariate analyses, higher LNR and multiple liver metastatic tumors were identified as the independent prognostic factors for both OS and RFS. Elevated LNR was significantly associated with advanced pN stage (P <0.001), larger primary tumor size (P = 0.046), the presence of microvascular invasion (P = 0.008), and neoadjuvant chemotherapy (P = 0.004). LNR may be prognostic indicator for patients with GCLM treated by synchronous surgical resection. Patients with lower LNR and single liver metastasis may gain more survival benefits from the surgical resection. Further prospective studies with reasonable study design are warranted.