Phase III Trial Comparing Intraperitoneal and Intravenous Paclitaxel Plus S-1 Versus Cisplatin Plus S-1 in Patients With Gastric Cancer With Peritoneal Metastasis: PHOENIX-GC Trial

The Burden of Peritoneal Metastases from Gastric Cancer: A Systematic Review on the Incidence, Risk Factors and Survival

The peritoneum is a common metastatic site in gastric cancer. This systematic review provides an overview of the incidence, risk factors and survival of synchronous peritoneal metastases from gastric cancer. A systematic search was performed to identify studies wherein the incidence, risk factors and survival of gastric cancer with peritoneal metastases were investigated. Of all 38 potentially eligible studies, 17 studies were included based on the eligibility criteria. The incidence of synchronous gastric peritoneal metastases was reviewed for population-based studies (10–21%), for observational cohort studies (2–15%) and for surgical cohort studies (13–40%). Potential risk factors for synchronous gastric peritoneal metastases were younger age, non-cardia gastric cancer, female sex, signet ring cell carcinoma, diffuse type histology or linitis plastica, T4 stage, Hispanic ethnicity and more than one metastatic location. Synchronous peritoneal metastases are commonly diagnosed in patients with gastric cancer with an incidence up to 21% in recent population-based studies. Furthermore, prognosis of patients with gastric peritoneal metastases is poor with median overall survival ranging from 2 to 9 months. The high incidence and poor prognosis require intensive research on diagnostic features and effective treatment options to improve survival.

Prognosis of poorly cohesive gastric cancer after complete cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy (CYTO-CHIP study)

BACKGROUND

The incidence of gastric poorly cohesive carcinoma (PCC) is increasing. The prognosis for patients with peritoneal metastases remains poor and the role of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is controversial. The aim was to clarify the impact of gastric PCC with peritoneal metastases treated by CRS with or without HIPEC.

METHODS

All patients with peritoneal metastases from gastric cancer treated with CRS with or without HIPEC, in 19 French centres, between 1989 and 2014, were identified from institutional databases. Clinicopathological characteristics and outcomes were compared between PCC and non-PCC subtypes, and the possible benefit of HIPEC was assessed.

RESULTS

In total, 277 patients were included (188 PCC, 89 non-PCC). HIPEC was performed in 180 of 277 patients (65 per cent), including 124 of 188 with PCC (66 per cent). Median overall survival (OS) was 14.7 (95 per cent c.i. 12.7 to 17.3) months in the PCC group versus 21.2 (14.7 to 36.4) months in the non-PCC group (P < 0.001). In multivariable analyses, PCC (hazard ratio (HR) 1.51, 95 per cent c.i. 1.01 to 2.25; P = 0.044) was associated with poorer OS, as were pN3, Peritoneal Cancer Index (PCI), and resection with a completeness of cytoreduction score of 1, whereas HIPEC was associated with improved OS (HR 0.52; P < 0.001). The benefit of CRS-HIPEC over CRS alone was consistent, irrespective of histology, with a median OS of 16.7 versus 11.3 months (HR 0.60, 0.39 to 0.92; P = 0.018) in the PCC group, and 34.5 versus 14.3 months (HR 0.43, 0.25 to 0.75; P = 0.003) in the non-PCC group. Non-PCC and HIPEC were independently associated with improved recurrence-free survival and fewer peritoneal recurrences. In patients who underwent HIPEC, PCI values of below 7 and less than 13 were predictive of OS in PCC and non-PCC populations respectively.

CONCLUSION

In selected patients, CRS-HIPEC offers acceptable outcomes among those with gastric PCC and long survival for patients without PCC.

Clinical Outcome for Patients Managed with Low-Dose Cisplatin and Doxorubicin Delivered as Pressurized Intraperitoneal Aerosol Chemotherapy for Unresectable Peritoneal Metastases of Gastric Cancer

BACKGROUND

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is increasingly used to manage gastric cancer peritoneal metastasis (GCPM).

METHODS

This study analyzed a prospective database of GCPM patients treated with cisplatin and doxorubicin PIPAC (PIPAC-C/D). The outcome criteria were adverse events, pathologic response [peritoneal regression grading score (PRGS)], and overall survival (OS).

RESULTS

The PIPAC-C/D procedure was scheduled for 144 patients with a median age of 57 years (range 22-88 years). Access to the abdominal cavity for the first PIPAC failed in 11 patients (7.7 %). A total of 296 procedures were performed for 131 patients. Of the 144 patients, 52 (36.1%) underwent one PIPAC, 32 (22.2%) underwent two PIPACs, 24 (16.7%) underwent three PIPACs, and 21 (14.6%) underwent four or more PIPACs. The overall morbidity/mortality was grade 1 for 22 patients (15.3%), grade 2 for 32 patients (22.2%), grade 3 for 7 patients (4.9%), grade 4 for no patients (0%), and grade 5 for 2 patients (1.4%). Of the 37 patients who had three or more PIPACs eligible for histopathologic response analysis, 27 (73%) had major or complete regression (PRGS 1/2). A median OS of 11 months (range 0-61 months) for the total study population and 16 months (range 2-61 months) for the patients with three or more PIPACs was observed. For 10 patients (7%) who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy, the median OS was 15 months (minimum, 4 months; maximum, 27 months). Multivariate analysis showed three or more PIPACs to be an independent prognostic factor for improved OS (hazard ratio, 0.36; p < 0.0001).

CONCLUSIONS

Repetitive PIPAC-C/D ± systemic chemotherapy is associated with low morbidity and mortality rates. Prospective randomized trials are needed to confirm whether three or more PIPAC-C/Ds improve clinical outcome.

Circular RNA circ_ASAP2 regulates drug sensitivity and functional behaviors of cisplatin-resistant gastric cancer cells by the miR-330-3p/NT5E axis

This study aims to explore the biological actions of circular RNA (circRNA) ArfGAP with SH3 domain, ankyrin repeat and PH domain 2 (circ_ASAP2, circ_0006089) in cisplatin (DDP) resistance of gastric cancer. Circ_ASAP2, ecto-5'-nucleotidase (NT5E) and miR-330-3p were quantified by quantitative real-time PCR or western blot. The measurements of the IC50 value and cell proliferation were done using 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell colony formation, cell cycle distribution, apoptosis, migration and invasion were evaluated by the colony formation, flow cytometry and transwell assays. Dual-luciferase reporter assay was performed to confirm the targeted relationship between different molecules. The role of circ_ASAP2 in tumor growth was gauged by in vivo animal studies. Circ_ASAP2 and NT5E were overexpressed in DDP-resistant gastric cancer tissues and cells. Knockdown of circ_ASAP2 promoted DDP sensitivity, apoptosis and repressed proliferation, migration and invasion of DDP-resistant gastric cancer cells in vitro and diminished tumor growth in vivo. Moreover, NT5E was a downstream effector of circ_ASAP2 in regulating cell DDP sensitivity and functional behaviors. Mechanistically, circ_ASAP2 directly bound to miR-330-3p to promote NT5E expression. Furthermore, circ_ASAP2 modulated cell DDP sensitivity and functional behaviors by targeting miR-330-3p. Knockdown of circ_ASAP2 promoted DDP sensitivity and suppressed malignant behaviors of DDP-resistant gastric cancer cells through targeting the miR-330-3p/NT5E axis.

A Proposed New Clinical Classification of Metastatic Gastric Cancer - Pyloric and Antral Gastric Cancer

BACKGROUND

We aimed to classify metastatic pyloric/antral gastric cancer in terms of macroscopic morphology and metastatic form.

METHODS

Thirty-eight patients with pyloric/antral gastric cancer were included in the study. Patients were classified according to a combination of Borrmann classification type and metastatic type, and the clinicopathological characteristics of each group were compared.

RESULT

Of the 38 patients, 33 (type II: 9 and type III: 24) (87%) had ulcerative gastric cancer. Ulcerative gastric cancer was classified into four groups: lymphatic only group (L+H-P-), lymphatic + hematogenous group (L+H+P-), disseminated ± lymphatic group (L±H-P+), and lymphatic + hematogenous + disseminated group (L+H+P+). In the L+H-P- group, all patients had bulky lymph nodes and serum levels of both carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were high; the condition of patients was good, and the therapeutic response was good. In the L+H+P- group, metastases other than liver metastases were rare, and serum CEA levels were high. In the L±H-P+ group, the predominant histological type was signet ring cell carcinoma; both serum CEA and CA19-9 levels were low. Patients in the L+H+P+ group had higher serum CA19-9 levels and were more prone to hematogenous metastasis to various organs; these patients had worse patient status and lower treatment response. Gastric cancer other than ulcerative type was only detected in five patients (type V: 3, type IV: 1, type I: 1).

CONCLUSION

Classification by a combination of macroscopic and metastatic form in pyloric/antral metastatic gastric cancer might be useful for diagnosis and treatment.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of gastric cancer, 2021

There exist differences in the epidemiological characteristics, clinicopathological features, tumor biological characteristics, treatment patterns, and drug selections between gastric cancer patients from the Eastern and Western countries. The Chinese Society of Clinical Oncology (CSCO) has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually. Taking into account regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted expert consensus judgment 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 in China. The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis, treatment, follow-up, and screening of gastric cancer. Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines, this updated guideline integrates the results of major clinical studies from China and overseas for the past year, focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations. For the comprehensive treatment of non-metastatic gastric cancer, attentions were paid to neoadjuvant treatment. The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated. For the comprehensive treatment of metastatic gastric cancer, recommendations for immunotherapy were included, and immune checkpoint inhibitors from third-line to the first-line of treatment for different patient groups with detailed notes are provided.

Improved prognosis of pancreatic cancer patients with peritoneal metastasis

BACKGROUND

Peritoneal metastasis is one of the most important poor prognostic factors in advanced pancreatic cancer (PC). Whether the prognosis of PC with peritoneal metastasis has improved with the advent of gemcitabine plus nab-paclitaxel (GnP) and modified FOLFIRINOX (mFFX) is uncertain. The aim of this study was to evaluate the improvements in treatment outcomes of PC with peritoneal metastasis.

METHODS

We retrospectively investigated consecutive PC patients with peritoneal metastasis treated with chemotherapy at our institution between 2010 and 2019. We compared the clinical characteristics and survival outcomes according to the period of diagnosis (group A, 2010-2014; group B, 2015-2019) and chemotherapy regimen. We also examined the prognostic factors for overall survival (OS).

RESULTS

Among 180 patients included (GnP 88; mFFX 14; other regimens 78), distant metastasis was confined to the peritoneum in 89 patients. Although group B had a worse performance status compared to group A, median OS was significantly longer in group B. GnP and mFFX showed a significantly higher objective response rate and disease control rate in addition to longer progression free survival and OS compared to other regimens. The administration of GnP or mFFX, performance status, and neutrophil to lymphocyte ratio ≥5 were identified as independent prognostic factors for OS. Furthermore, the amount of ascites and extent of peritoneal metastasis were significantly associated with OS in patients with distant metastasis confined to the peritoneum.

CONCLUSIONS

The prognosis of PC with peritoneal metastasis has significantly improved over time with the advent of GnP and mFFX.

Neoadjuvant Intraperitoneal and Systemic Chemotherapy Versus Neoadjuvant Systemic Chemotherapy With Docetaxel, Oxaliplatin, and S-1 for Gastric Cancer With Peritoneal Metastasis: A Propensity Score Matched Analysis

BACKGROUND

The optimal treatment for gastric cancer with peritoneal metastasis (GCPM) remains debatable. This study aimed to compare the efficacy and safety of neoadjuvant intraperitoneal and systemic chemotherapy (NIPS) versus neoadjuvant systemic chemotherapy (NSC) for GCPM.

METHODS

Patients of GCPM received neoadjuvant chemotherapy with docetaxel, oxaliplatin and S-1 between January 2011 and June 2019 were retrospectively evaluated. Propensity score matched (PSM) analysis was carried out to reduce the selection bias. Multivariate Cox regression model was applied to screen the prognostic factors.

RESULTS

After PSM processing, 71 patients in each group were matched among the 186 GCPM patients included. NIPS yielded a better ascites and cytology response to chemotherapy, higher conversion resection rate and R0 resection rate than NSC. The overall survival (OS) rate in NIPS group was better than that in NSC group. Multivariate analysis revealed that the P stage, ascites response, conversion surgery rate and R0 resection rate were independent prognostic factors. Subgroup analysis indicated that NIPS showed a survival benefit over NSC only in patients with cT3-4a, P1-2, whose cytology turned negative, and who received conversion surgery; while not in patients with cT4b, P0 or P3, whose cytology did not turn negative, or who did not receive conversion surgery.

CONCLUSIONS

NIPS is a safe and feasible treatment for GCPM, which showed more benefit than NSC.

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.

History and emerging trends in chemotherapy for gastric cancer

Chemotherapy is indispensable for gastric cancer. For unresectable and/or recurrent gastric cancer, first-line chemotherapy consists of multidrug regimens including oral 5-FU agents such as S1/Xeloda and platinum preparations, as well as Trastuzumab, which is effective in HER2-positive cases. Second- and third-line chemotherapy regimens include taxanes, Ramucirumab (R-mab), and Nivolumab (N-mab), which have different mechanisms of action from first-line chemotherapy. R-mab is molecularly targeted to vascular endothelial growth factor receptor 2 in the host cells, but its indication is not conditional. For resectable gastric cancer, in Eastern countries, postoperative adjuvant chemotherapy has been successful, including S1, Docetaxel/S1 (DS), and Xeloda/Oxaliplatin (Xelox) regimens, whereas, in Western countries, the 5-FU/Leucovorin/Oxaliplatin/Docetaxel (FLOT) regimen was recently shown to be effective in the perioperative chemotherapy setting. Most recently, however, in Eastern countries, perioperative SOX was demonstrated to be effective in specific advanced gastric cancer. For stage IV gastric cancer, new therapeutic strategies have been proposed such as neoadjuvant chemotherapy and conversion surgery, and cures can be conditionally obtained. Recent genomic understanding of gastric cancer proposed a diversity of molecular targets by molecular profiling. Such optimized chemotherapy regimens, according to the specific clinical situations, have been rigorously established for the best survival of advanced gastric cancer.

Development of rotational intraperitoneal pressurized aerosol chemotherapy to enhance drug delivery into the peritoneum

This study aims to evaluate the drug distribution, tissue concentrations, penetration depth, pharmacokinetic properties, and toxicities after rotational intraperitoneal pressurized aerosol chemotherapy (RIPAC) in pigs. Because relevant medical devices have not been introduced, we developed our prototype of pressurized intraperitoneal aerosol chemotherapy (PIPAC) and RIPAC by adding a conical pendulum motion device for rotating the nozzle. RIPAC and PIPAC were conducted using 150 ml of 1% methylene blue to evaluate the drug distribution and 3.5 mg of doxorubicin in 50 ml of 0.9% NaCl to evaluate the tissue concentrations and penetration depth, pharmacokinetic properties, and toxicities. All agents were sprayed as aerosols via the nozzle, DreamPen^® (Dalim Biotech, Gangwon, South Korea), with a velocity of 5 km/h at a flow rate of 30 ml/min under a pressure of 7 bars, and capnoperitoneum of 12 mmHg was maintained for 30 min. As a result, RIPAC showed a wider distribution and stronger intensity than PIPAC. Compared with PIPAC, RIPAC demonstrated high values of the tissue concentration in the central, right upper, epigastrium, left upper, left lower, right lower, and right flank regions (median, 375.5-2124.9 vs. 161.7-1240 ng/ml; p ≤ .05), and higher values of the depth of concentrated diffusion and depth of maximal diffusion (median, 232.5-392.7 vs. 116.9-240.1 μm; 291.2-551.2 vs. 250.5-362.4 μm; p ≤ .05) in all regions except for bowels. In RIPAC, the pharmacokinetic properties reflected hemodynamic changes during capnoperitoneum, and there were no related toxicities. Conclusively, RIPAC may have the potential to enhance drug delivery into the peritoneum compared to PIPAC.

Comparative Outcomes of Laparoscopic Gastrectomy and Open Gastrectomy for Scirrhous Gastric Cancer: A Multicenter Retrospective Cohort Study

Objective

A multicenter retrospective cohort study was performed to compare the outcomes of laparoscopic gastrectomy (LG) versus open gastrectomy (OG) for scirrhous gastric cancer (GC) as a unique subtype also known as type 4 gastric cancer or linitis plastica.

Background

Although data on the efficacy and safety of LG as an alternative to OG are emerging, the applicability of LG to scirrhous GC remains unclear.

Methods

Patients with clinical type 4 GC undergoing gastrectomy at 13 hospitals from 2005 to 2015 were retrospectively reviewed. As the primary endpoint, we compared overall survival (OS) between the LG and OG groups. To adjust for confounding factors, we used multivariate Cox regression analysis for the main analyses and propensity-score matching for sensitivity analysis. Short-term outcomes and recurrence-free survival were also compared.

Results

A total of 288 patients (LG, 62; OG, 226) were included in the main analysis. Postoperative complications occurred in 25.8% and 30.1%, respectively (P = 0.44). No significant difference in recurrence-free survival was observed (P = 0.72). The 5-year OS rates were 32.4% and 31.6% in the LG and OG groups, respectively (P = 0.60). The hazard ratio (LG/OG) for OS was 0.98 (95% confidence interval [CI], 0.65-1.43) in the multivariate regression analysis. In the sensitivity analyses after propensity-score matching, the hazard ratio for OS was 0.92 (95% CI, 0.58-1.45).

Conclusions

Considering the hazard ratios and 95% CIs for OS, LG for scirrhous GC was not associated with worse survival than that for OG.

Long-term response on letrozole for gastric cancer: A case report

RATIONALE

Hormone therapies, particularly those targeting estrogen and its receptors, are a key treatment modality for patients with estrogen receptor (ER)-positive breast or ovarian cancer. Some gastric cancers (GCs) express ERs, and preclinical studies suggest the potential of estrogen-targeting hormone therapy on GC; however, the clinical relevance of this hormone therapy on GC treatment has not been well elucidated.

PATIENT CONCERNS

An 80-year-old female was admitted to our department with hypogastric pain and vomiting. Computed tomography demonstrated small bowel obstruction, and laparotomy after bowel decompression revealed peritoneal dissemination consisting of a poorly-differentiated adenocarcinoma. Intestinal bypass between the ileum and transverse colon was performed.

DIAGNOSES

The tumor was ER- and mammaglobin-positive, indicating that it originated from a breast cancer. Diagnostic imaging revealed no evidence of breast cancer; however, right axillary ER- and mammaglobin-positive lymphadenopathy was found.

INTERVENTIONS

The patient received hormone therapy using letrozole based on a clinical diagnosis of occult breast cancer with peritoneal dissemination and right axillary lymph node metastasis.

OUTCOMES

The patient remained disease free until 37 months but deceased at 53 months from the onset of disease. An autopsy revealed no tumor cells in the right breast tissue; however, there was a massive invasion of cancer cells in the stomach.

LESSONS

A patient with ER positive GC with peritoneal dissemination and right axillary lymph node metastasis presented remarkable response to letrozole. The long-term survival obtained using letrozole for a patient with GC with distant metastasis suggests the potential of estrogen targeting hormone therapies for GC.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Identification of novel autoantibodies in ascites of relapsed paclitaxel-resistant gastric cancer with peritoneal metastasis using immunome protein microarrays and proteomics

BACKGROUND

Gastric cancer (GC) patients with peritoneal metastasis usually have extremely poor prognosis. Intraperitoneal infusion of paclitaxel (PTX) provides an effective treatment, but relapse and PTX-resistance are unavoidable disadvantages, and it is difficult to monitor the occurrence of PTX-resistance.

OBJECTIVE

The aim of this study was to explore novel autoantibodies in the ascites of individuals with relapsed PTX-resistant GC with peritoneal metastasis.

METHODS

Ascites samples were collected before PTX infusion and after the relapse in 3 GC patients. To determine the expression of significantly changed proteins, we performed autoantibody profiling with immunome protein microarrays and tandem mass tag (TMT) quantitative proteomics, and then, the overlapping proteins were selected.

RESULTS

Thirty-eight autoantibodies that were differentially expressed between the ascites in the untreated group and relapsed PTX-resistant group were identified. For confirmation of the results, TMT quantitative proteomics was performed, and 842 dysregulated proteins were identified. Four proteins, TPM3, EFHD2, KRT19 and vimentin, overlapped between these two assays.

CONCLUSIONS

Our results first revealed that TPM3, EFHD2, KRT19 and vimentin were novel autoantibodies in the ascites of relapsed PTX-resistant GC patients. These autoantibodies may be used as potential biomarkers to monitor the occurrence of PTX-resistance.

The Landmark Series: Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC) for Treatment of Gastric Cancer Metastatic to Peritoneum

Gastric cancer (GC) is a common cancer worldwide, with patients developing isolated peritoneal metastases (PM) in approximately 30% of cases. In patients with PM, prognosis is quite poor, and long-term survival is almost zero. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been demonstrated to be an effective treatment in many peritoneal malignancies, including appendiceal and ovarian cancers and in peritoneal mesothelioma. In this educational review, we summarize many of the seminal studies addressing the potential benefit of CRS/HIPEC for patients with gastric cancer and peritoneal metastases (GC/PM).

G-protein subunit gamma-4 expression has potential for detection, prediction and therapeutic targeting in liver metastasis of gastric cancer

BACKGROUND

The liver is the most common site for haematogenous metastasis of gastric cancer, and liver metastasis is fatal.

METHODS

We conducted a transcriptomic analysis between metastatic foci in the liver, primary tumour and adjacent tissues from gastric cancer patients with metastasis limited to the liver. We determined mRNA expression levels in tumour tissues of 300 patients with gastric cancer via quantitative RT-PCR. The oncogenic phenotypes of GNG4 were determined with knockdown, knockout and forced expression experiments. We established and compared subcutaneous and liver metastatic mouse xenograft models of gastric cancer to reveal the roles of GNG4 in tumorigenesis in the liver.

RESULTS

GNG4 was upregulated substantially in primary gastric cancer tissues as well as liver metastatic lesions. High levels of GNG4 in primary cancer tissues were associated with short overall survival and the likelihood of liver recurrence. Functional assays revealed that GNG4 promoted cancer cell proliferation, the cell cycle and adhesiveness. Tumour formation by GNG4-knockout cells was moderately reduced in the subcutaneous mouse model and strikingly attenuated in the liver metastasis mouse model.

CONCLUSIONS

GNG4 expression may provide better disease monitoring for liver metastasis, and GNG4 may be a novel candidate therapeutic target for liver metastasis.

Retrospective Cohort Study of Intraoperative Administration of Sustained-Release 5-Fluorouracil Implants in Advanced Gastric Cancer Patients

Background: 5-fluorouracil (5-FU) is basically used in the field of postoperative chemotherapy of gastric cancer (GC), the goal of this study was to evaluate improvement of long-term survival rate among GC patients after the 5-FU implants treatment.

Methods: The study included 145 patients with gastric cancer who received postoperative chemotherapy with 5-FU implants and had complete follow-up information. According to the sex, age and clinical stage of 5-FU implants group, 74 patients were matched as the control group at the same time. In the study, we compared the 5-year overall survival rate with progression-free survival rate in the two groups, and the drug safety for both groups during the treatment was also compared.

Results: The median follow-up time was 85 months (range 60–116 months). 31 patients (21.38%) died of tumor recurrence in 5-FU implants group and 21 (28.38%) in control group. In the control group, metastatic lesions were found in the small intestine, left adrenal gland and peritoneum in three patients. The 5-year progression-free survival (PFS) rate was 79.71% in 5-FU group and 67.12% in control (p = 0.0045). The 5-year overall survival (OS) rate was 77.68% in 5-FU implants group and 64.87% in control (p = 0.0159). Both the 5-years OS and PFS rates in 5-FU group were better than control group without significant side effect.

Conclusions: 5-FU implants may improve 5-years OS and PFS rates after surgery in gastric cancer patients, while good safety profile suggests it could be reliable.

Intraperitoneal paclitaxel: pharmacology, clinical results and future prospects

Paclitaxel administered into the peritoneal cavity is a chemotherapy agent that shows unusually prolonged retention within the peritoneal space. Using this pharmacokinetic fact as a starting point, the use of this drug to benefit patients with peritoneal metastases was investigated. The pharmacokinetics and drug characteristics of paclitaxel were identified from the oncologic literature. The experience to date with ovarian cancer, malignant peritoneal mesothelioma, gastric cancer and pancreas cancer was explored. Paclitaxel given by repeated instillation through an intraperitoneal port has demonstrable responses in ovarian cancer, peritoneal mesothelioma, gastric cancer and pancreas cancer when peritoneal metastases are present. Its role for prevention of peritoneal metastases in patients at high risk seems less well established. Randomized controlled studies have been positive in ovarian cancer but not in other diseases with peritoneal dissemination. A randomized controlled study in gastric cancer with peritoneal metastases produced suggestive but not conclusive results. Conversion surgery after repeated treatments with intraperitoneal paclitaxel has been reported with gastric cancer and pancreas cancer with peritoneal metastases. The pharmacology of intraperitoneal paclitaxel strongly suggest that intraperitoneal administration should be of benefit to prevent or treat peritoneal metastases. Protocols that the oncologist can follow to realize these potential benefits are not as yet available.

Intraperitoneal chemotherapy in the treatment of gastric cancer peritoneal metastases: an overview of common therapeutic regimens

Peritoneal metastasis (PM) have an incidence of 10-20% in patients with gastric cancer (GC), and even up to 40% in patients with UICC Stage III GC. Due to the aggressive characteristic of adenocarcinoma of the stomach, GC is the third leading cause of cancer deaths worldwide. For GC with PM, the treatment of choice is according to national and international guidelines systemic chemotherapy, combined with biologic therapy against specific receptor antigen in with overexpression, such as HER-2. Multimodal treatment regimens including intraperitoneal application of chemotherapy and cytoreductive surgery (CRS) have been investigated and established all over the world. Driven by pharmacological studies and thoughts considering the increased benefits of cytotoxic agents used in the abdominal cavity, several drugs and drug combinations are widely used. In order to standardize treatment protocols, it is crucial to differentiate between normothermic and hyperthermic intraperitoneal chemotherapy (NIPEC, HIPEC). The requirements of an ideal cytotoxic drug different obviously dependent on its application method. Because of their high molecular weight and lipophilic structure, taxanes, such as paclitaxel or docetaxel have a long intraperitoneal retention time and are commonly used in NIPEC, while platin derivates, such as carboplatin or oxaliplatin are known for their synergistic effect to heat and are chosen in HIPEC. This review aims to explore and summarize different intraperitoneal treatment regimens strictly evaluated by supporting evidence in an effort to consolidate many regimens to a few evidence-based treatment protocols that deserve further investigation and distribution. This analysis included all studies focusing on intraperitoneal chemotherapy: Phase II, Phase III trials and non-randomized retrospective trials of larger cohorts of patients with GC and established PM or risk of PM. Interestingly, the protocols for NIPEC are quite uniform, with less variation between the therapeutic components in contrast to the different HIPEC protocols. This difference might be explained by the divergent evolution of NIPEC and HIPEC, as the former exclusively originated in Japan, while HIPEC experienced a more multicentric evolution and distribution in the United States, Asia, Europe, and worldwide utilization today.

Surgery with hyperthermic intraperitoneal chemotherapy after response to induction chemotherapy in patients with peritoneal metastasis of gastric cancer

Background

Gastric cancer (GC) with peritoneal metastases (PM) has a dismal prognosis and to date only a few management options have been reported. Of those, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) after induction bidirectional intraperitoneal and systemic chemotherapy (BIPSC) appear as a promising treatment option for these patients. Outcome data including safety and efficacy of CRS with radical Gastrectomy and HIPEC after response to combination of laparoscopic HIPEC (LHIPEC) with BIPSC as an induction therapy in patients with PM of GC was evaluated in this retrospective observational study.

Methods

Diagnostic Laparoscopy was performed in 53 patients with PM of GC who admitted to the Center for Treatment of Peritoneal Surface Malignancies, Istanbul, between 2013 and 2016. Peritoneal cancer index (PCI), ascites status and cytology were determined. The patients underwent LHIPEC and then, BIPSC induction chemotherapy using intraperitoneal docetaxel (30 mg/m²) and cisplatin (30 mg/m²) and intravenous Docetaxel/Cisplatin/5-Fluorouracil (DCF) for 3 cycles. In selected patients, CRS with radical gastrectomy and HIPEC were performed after the response to induction therapy. BIPSC was continued for 3 more cycles with a dose reduction in an adjuvant setting.

Results

All LHIPEC procedures were uneventful with Grade 1-2 side effects (11/53, 20,8%). As a response to induction chemotherapy PCI was reduced from 19.6±8 (range, 6-39) to 13.6±9.8 (range, 1-39) (P<0.001). Ascites was detected in 55% (29 out of 53) and cytology was positive in 51% (27 out of 53) of the patients before induction chemotherapy. Ascites was completely abolished and all cytology became negative. Then, 34 of 53 (64.15%) patients underwent CRS with radical gastrectomy and HIPEC. CC0/1 resection was achieved in 22 (64.70%) of patients (P<0.05). The median survival time was 18.9±13.4 (95% CI: 15.2-22.6 months. Combined surgery and HIPEC related mortality occurred in 1 out of 34 patients (2.9%) due to developed diffuse intravascular coagulation at postoperative day 2. Grade 2 operative complications included biliary fistula in one, and duodenal stump leakage in two patients (8.7%). All of the fistula closed with conservative management. The median survival time was 18.9±13.4 months and the median progression-free survival time was 15.6±12.9 with 1-, 2-, and 5-year survival rates of 82.4%, 59% and 17.6% in patients with PM of GC. Multivariate analysis identified high peritoneal cancer index (P=0.000) and complete resection (P<0.05) as independent predictors for better progression-free and overall survival.

Conclusions

The best outcomes can be expected with optimal cytoreduction and limited peritoneal dissemination in response to induction chemotherapy. Knowledgeable selection of patients with PM of GC is essential to perform surgery with HIPEC safely with acceptable mortality and morbidity.

Conversion surgery in patients with pancreatic cancer and peritoneal metastasis

Background

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal malignancies globally. We have previously explored the clinical efficacy of intraperitoneal (IP) paclitaxel therapy for patients with PDAC and peritoneal metastasis, which demonstrated favourable response and disease control rates. However, the real implications of conversion surgery after IP therapy remain unclear.

Methods

We conducted two multicenter clinical trials of IP therapy with paclitaxel in patients with PDAC and peritoneal metastasis. We focused on patients who underwent conversion surgery and investigated the long-term outcomes, particularly, initial recurrence patterns and long-term survival.

Results

Seventy-nine patients with PDAC and peritoneal metastasis were treated, and 33 (41.8%) patients received SP (intravenous IP paclitaxel with S-1) and 46 (58.3%) were administered GAP (intravenous gemcitabine + nab-paclitaxel combined with IP paclitaxel) combination therapy. Of the 79 patients, 16 (20.3%) underwent conversion surgery. The median time to surgery was 9.0 (range, 4.1-13.0) months after the initiation of chemotherapy. Finally, 13 (81.3%) patients underwent R0 resection. Evans grade was IIA in nine patients, IIB in four patients, III in two patients, and IV in one patient. The median overall survival time in patients who underwent conversion surgery was 32.5 (range, 13.5-66.9) months. Twelve (75.0%) patients were found to have experienced recurrence after conversion surgery. Especially, peritoneal recurrence was observed in 50% of patients as the initial recurrence pattern. The median recurrence-free survival time was 9.2 (range, 5.1-32.8) months, and three patients have survived without recurrence to date.

Conclusions

Our IP therapy displays promising clinical efficacy with acceptable tolerability in patients with PDAC and peritoneal metastasis. Although we could observe some super-responders in the cohort, further improvements in IP therapy are warranted.

Phase II trial of prophylactic hyperthermic intraperitoneal chemotherapy in patients with locally advanced gastric cancer after curative surgery

Background

HIPEC is an emerging procedure to treat peritoneal metastasis of gastric cancer. Data about HIPEC in locally advanced gastric cancer is scarce. The purpose of this trial is to evaluate the safety and toxicity of prophylactic HIPEC with cisplatin for patients with locally advanced gastric cancer.

Methods

From March 2015 to November 2016, a prospective, randomized phase II trial was conducted. After radical gastrectomy, patients in the experimental group underwent HIPEC with cisplatin followed by adjuvant chemotherapy with SOX regime. Patients in the other group were treated with SOX regime alone. Postoperative complications and patient survival were compared.

Results

In total, 50 patients were eligible for analyses. No significant difference was found in the incidence of postoperative complications including anastomotic/intestinal leakage, liver dysfunction, bone marrow suppression, wound infection and ileus (P > 0.05). Mean duration of hospitalization after radical gastrectomy was 11.7 days. 12.2 days in experimental group and 10.8 days in control group respectively (P = 0.255). The percentage of patients with elevated tumor markers was 12.1% in experimental group, which was significantly lower than 41.2% in control group (P = 0.02). 3-year RFS of patients who treated with or without prophylactic HIPEC were 84.8 and 88.2% respectively (P = 0.986). In the multivariate analysis, pathological T stage was the only independent risk factor for the RFS of patients (P = 0.012, HR =15.071).

Conclusion

Additional intraoperative HIPEC with cisplatin did not increase postoperative complications for locally advanced gastric cancer after curative surgery. Prophylactic HIPEC with cisplatin was safe and tolerable, while it did not reduce the risk of peritoneal recurrence in this trial, supporting further studies to validate the efficacy of it.

Trial registration

Chinese Clinical Trial Registry, ChiCTR2000038331. Registered 18 September 2020 - Retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=59692.

Applying a random projection algorithm to optimize machine learning model for predicting peritoneal metastasis in gastric cancer patients using CT images

BACKGROUND AND OBJECTIVE

Non-invasively predicting the risk of cancer metastasis before surgery can play an essential role in determining which patients can benefit from neoadjuvant chemotherapy. This study aims to investigate and test the advantages of applying a random projection algorithm to develop and optimize a radiomics-based machine learning model to predict peritoneal metastasis in gastric cancer patients using a small and imbalanced computed tomography (CT) image dataset.

METHODS

A retrospective dataset involving CT images acquired from 159 patients is assembled, including 121 and 38 cases with and without peritoneal metastasis, respectively. A computer-aided detection scheme is first applied to segment primary gastric tumor volumes and initially compute 315 image features. Then, five gradients boosting machine (GBM) models embedded with five feature selection methods (including random projection algorithm, principal component analysis, least absolute shrinkage, and selection operator, maximum relevance and minimum redundancy, and recursive feature elimination) along with a synthetic minority oversampling technique, are built to predict the risk of peritoneal metastasis. All GBM models are trained and tested using a leave-one-case-out cross-validation method.

RESULTS

Results show that the GBM model embedded with a random projection algorithm yields a significantly higher prediction accuracy (71.2%) than the other four GBM models (p<0.05). The precision, sensitivity, and specificity of this optimal GBM model are 65.78%, 43.10%, and 87.12%, respectively.

CONCLUSIONS

This study demonstrates that CT images of the primary gastric tumors contain discriminatory information to predict the risk of peritoneal metastasis, and a random projection algorithm is a promising method to generate optimal feature vector, improving the performance of machine learning based prediction models.

Transcriptomic Profiling Identifies a Risk Stratification Signature for Predicting Peritoneal Recurrence and Micrometastasis in Gastric Cancer

PURPOSE

Gastric cancer peritoneal carcinomatosis is fatal. Delay in detection of peritoneal metastases contributes to high mortality, highlighting the need to develop biomarkers that can help identify patients at high risk for peritoneal recurrence or metastasis.

EXPERIMENTAL DESIGN

We performed a systematic discovery and validation for the identification of peritoneal recurrence prediction and peritoneal metastasis detection biomarkers by analyzing expression profiling datasets from 249 patients with gastric cancer, followed by analysis of 426 patients from three cohorts for clinical validation.

RESULTS

Genome-wide expression profiling identified a 12-gene panel for robust prediction of peritoneal recurrence in patients with gastric cancer (AUC = 0.95), which was successfully validated in a second dataset (AUC = 0.86). Examination of 216 specimens from a training cohort allowed us to establish a six gene-based risk-prediction model [AUC = 0.72; 95% confidence interval (CI): 0.66-0.78], which was subsequently validated in an independent cohort of 111 patients with gastric cancer (AUC = 0.76; 95% CI: 0.67-0.83). In both cohorts, combining tumor morphology and depth of invasion further improved the predictive accuracy of the prediction model (AUC = 0.84). Thereafter, we evaluated the performance of the identical six-gene panel for its ability to detect peritoneal metastasis by analyzing 210 gastric cancer specimens (prior 111 patients plus additional 99 cases), which discriminated patients with and without peritoneal metastasis (AUC = 0.72). Finally, our biomarker panel was also remarkably effective for identifying peritoneal micrometastasis (AUC = 0.72), and its diagnostic accuracy was significantly enhanced when depth of invasion was included in the model (AUC = 0.85).

CONCLUSIONS

Our novel transcriptomic signature for risk stratification and identification of high-risk patients with peritoneal carcinomatosis might serve as an important clinical decision making in patients with gastric cancer.

Current status of conversion surgery for stage IV gastric cancer

Palliative chemotherapy with best supportive care is a mainstay for patients with gastric cancer (GC) and distant metastasis. However, with advances in GC chemotherapy, multimodal treatment, including perioperative chemotherapy plus conversion surgery, has attracted attention as a new strategy to improve the outcome of patients with stage IV disease. Conversion surgery is defined as surgical treatment aimed at R0 resection after a good response to induction chemotherapy for tumors originally considered unresectable or marginally resectable for technical and/or oncological reasons. Various biological characteristics differ, depending on each metastatic condition in stage IV GC. The main metastatic pathways of GC can be divided into three categories: lymphatic, hematogenous, and peritoneal. In each category, considerable historical data on conversion surgery have demonstrated the benefits of individualized approaches. However, owing to the diversity of these conditions, a common definition, including the choice of induction chemotherapy, optimal timing of resection, and eligibility for conversion surgery, has not been established among surgical oncologists. Thus, we explore the current and future treatment options by reviewing the literature on this controversial topic comprehensively.

Downregulation of CDH11 Promotes Metastasis and Resistance to Paclitaxel in Gastric Cancer Cells

Background: Gastric cancer (GC) with peritoneal metastasis has an extremely poor prognosis. Paclitaxel (PTX) intraperitoneal infusion provides an effective treatment for these patients. However, GC patients with peritoneal metastasis who receiving PTX treatments tend to occur PTX-resistance accompany with more aggressive ascites and metastasis. How does this happen is still unknown. Here, we aimed to explore the mechanisms that mediate PTX-resistance and metastasis in GC with peritoneal metastasis.

Methods: Ascites samples were collected before PTX infusion and after the relapse in 3 GC patients. To determine the expression of significantly changed proteins, we performed tandem mass tag (TMT) quantitative proteomics. Immunohistochemistry (IHC) staining and western blot were performed to confirm the expression of CDH11 in the PTX-resistant tissues and MKN45P-PR cells. Invasion and migration of GC cells were examined by in vitro transwell and wound healing assays and in vivo dissemination experiments.

Results: CDH11 expression was downregulated in the relapsed PTX-resistant ascites, tissues and the PTX-resistant cell line MKN45P-PR. Inhibition of CDH11 expression promoted the invasion, migration and PTX resistance of MKN45P cells, while overexpression of CDH11 repressed these biological functions. Moreover, tumors disseminated in the mice peritoneal cavity induced by MKN45P-PR cells and shCDH11 cells displayed higher metastatic ability and resistance to PTX treatment.

Conclusions: Our results reveal that CDH11 is inhibited in the relapsed PTX-resistant patients and the downregulated CDH11 expression promotes GC cell invasion, migration and PTX resistance. CDH11 may have the potential to serve as a predictable marker for the occurrence of PTX resistance in GC patients with peritoneal metastasis.

Intraperitoneal Paclitaxel Combined with S-1 Plus Oxaliplatin for Advanced Gastric Cancer with Peritoneal Metastasis: a Phase I Study

Purpose

We designed a new regimen by combining intraperitoneal (IP) paclitaxel (PTX) with systemic S-1 plus oxaliplatin (SOX) for the treatment of advanced gastric cancer with peritoneal metastasis. This dose-escalation study aimed to determine the maximum tolerated dose (MTD) and recommended dose (RD) of IP PTX administered weekly to patients.

Materials and Methods

Eight cycles of IP PTX plus SOX regimen were administered to the patients. S-1 was administered orally twice daily at a dose of 80 mg/m²/day for 14 consecutive days, followed by 7 days of rest. Intravenous oxaliplatin was administered at a fixed dose of 100 mg/m² on day 1, while IP PTX was administered on days 1 and 8. The initial dose of IP PTX was 40 mg/m², and the dose escalation was set in units of 20 mg/m² up to 80 mg/m². Dose-limiting toxicities (DLTs) were defined as grade 3 non-hematologic toxicities, grade 4 leukopenia, grade 3 febrile neutropenia, and grade 3 thrombocytopenia.

Results

Nine patients were included in the study. No DLTs were observed in any of the enrolled patients. Therefore, the MTD was not reached, and the RD of IP PTX was determined to be 80 mg/m². Four patients (44%) showed a decreased peritoneal cancer index score on second-look laparoscopic examination.

Conclusions

The present study determined the dose for further clinical trials of IP PTX to be 80 mg/m², when combined with a systemic SOX regimen.

Laparoscopic surgery for gastric cancer: Current status and future direction

Gastric cancer is still a major cause of death worldwide. While laparoscopic gastrectomy (LG) has gained evidence as a standard treatment for early gastric cancer in the distal stomach, there are still concerns regarding its application for gastric cancer in the upper stomach and advanced gastric cancer. Nevertheless, LG has shown to have faster recovery, shorter hospital stay, less pain, and less blood loss in many retrospective and prospective studies. The application of LG has now extended from conventional radical gastrectomy to novel approaches such as function-preserving gastrectomy and sentinel-node navigated surgery. Studies on the use of laparoscopy in treatment for stage IV gastric cancer are rare, but show that there may be some roles of LG in selected cases. With the development of new laparoscopic tools that augment human ability, the future of LG should move on from proving non-inferiority to demonstrating superiority compared to the traditional open gastrectomy.

Amido-Bridged Nucleic Acid-Modified Antisense Oligonucleotides Targeting SYT13 to Treat Peritoneal Metastasis of Gastric Cancer

Patients with peritoneal metastasis of gastric cancer have dismal prognosis, mainly because of inefficient systemic delivery of drugs to peritoneal tumors. We aimed to develop an intraperitoneal treatment strategy using amido-bridged nucleic acid (AmNA)-modified antisense oligonucleotides (ASOs) targeting synaptotagmin XIII (SYT13) and to identify the function of SYT13 in gastric cancer cells. We screened 71 candidate oligonucleotide sequences according to SYT13-knockdown efficacy, in vitro activity, and off-target effects. We evaluated the effects of SYT13 knockdown on cellular functions and signaling pathways, as well as the effects of intraperitoneal administration to mice of AmNA-modified anti-SYT13 ASOs. We selected the ASOs (designated hSYT13-4378 and hSYT13-4733) with the highest knockdown efficiencies and lowest off-target effects and determined their abilities to inhibit cellular functions associated with the metastatic potential of gastric cancer cells. We found that SYT13 interfered with focal adhesion kinase (FAK)-mediated intracellular signals. Intraperitoneal administration of hSYT13-4378 and hSYT13-4733 in a mouse xenograft model of metastasis inhibited the formation of peritoneal nodules and significantly increased survival. Reversible, dose- and sequence-dependent liver damage was induced by ASO treatment without causing abnormal morphological and histological changes in the brain. Intra-abdominal administration of AmNA-modified anti-SYT13 ASOs represents a promising strategy for treating peritoneal metastasis of gastric cancer.

Intraperitoneal Administration of Paclitaxel Combined with S-1 Plus Oxaliplatin as Induction Therapy for Patients with Advanced Gastric Cancer with Peritoneal Metastases

Background

Intraperitoneal (IP) administration of paclitaxel (PTX) has a great pharmacokinetic advantage to control peritoneal lesions and can be combined with various systemic chemotherapies. In this study, we evaluate the efficacy and tolerability of a combination of IP-PTX and systemic S-1/oxaliplatin (SOX) for induction chemotherapy for patients with peritoneal metastases (PM) from gastric cancer (GC).

Patients and Methods

Patients with GC who were diagnosed as macroscopic PM (P1) or positive peritoneal cytology (CY1) by staging laparoscopy between 2016 and 2019 were enrolled. PTX was IP administered at 40 mg/m² on days 1 and 8. Oxaliplatin was IV administered at 100 mg/m² on day 1, and S-1 was administered at 80 mg/m²/day for 14 consecutive days, repeated every 21 days. Survival time and toxicities were retrospectively explored.

Results

Forty-four patients received SOX + IP-PTX with a median (range) of 16 (1–48) courses, although oxaliplatin was suspended due to the hematotoxicity or intolerable peripheral neuropathy in many patients. The 1-year overall survival (OS) rate was 79.5% (95% CI 64.4–88.8%) with median survival time of 25.8 months. Gastrectomy was performed in 20 (45%) patients who showed macroscopic shrinkage of PM with a 1-year OS rate of 100% (95% CI 69.5–100%). Grade 2 and 3 histological responses was achieved in four (20%) and one (5%) patients. Grade 3/4 toxicities included neutropenia (11%), leukopenia (39%), and anemia (14%). There were no treatment-related deaths.

Conclusions

Combination chemotherapy using SOX + IP-PTX regimen is highly effective and recommended as induction chemotherapy for patients with PM from GC.

Prognostic impact of intraoperative peritoneal cytology after neoadjuvant therapy for potentially resectable pancreatic cancer

BACKGROUND

Neoadjuvant therapy (NAT) is considered a potential approach to improve survival for patients with pancreatic adenocarcinoma (PA). The objective of this study was to identify the clinical implications of washing peritoneal cytology (CY) status after NAT.

METHODS

Between 2005 and 2016, 151 consecutive patients with resectable (R)/borderline resectable (BR) PA underwent NAT with intention of subsequent resection at our institution. Of them, 13 and 123 patients underwent pancreatectomies with positive (CY+) and negative (CY-) cytology, respectively, while the remaining 15 patients did not undergo resection due to gross metastases at laparotomy. The clinicopathological factors influencing overall survival were clarified by the uni- and multivariate analyses.

RESULTS

The postoperative overall survival (OS) and disease-free survival (DFS) were markedly worse in patients who underwent resection with CY+, compared with those who were CY- (median OS, 14.8 m vs 30.8 m, p = 0.026, and median DFS 6.0 m vs 15.1 m, p = 0.008). According to the resectability by NCCN guidelines, CY+ indicates worse prognosis than CY- in R-PA patients (mOS: 30.1 m vs 71.1 m: p = 0.080). Similarly, in BR-PA patients, CY+ showed the significantly worse prognosis than CY- (mOS: 13.8 m vs 24.5 m: p = 0.048), which prognosis is comparable with patients who did not undergo resection. The multivariate analysis revealed that resectability, CY status and the induction of adjuvant therapy were significant predictors of postoperative OS (p = 0.007: Hazard ratio 2.264, 0.040:2.094 and 0.002:3.246, respectively).

CONCLUSIONS

CY+ is a significant predictor of poorer prognosis in PA patients after NAT. The subsequent pancreatectomies with CY+ after NAT do not contribute to prolonged survival.

Photodynamic Diagnosis and Therapy for Peritoneal Carcinomatosis from Gastrointestinal Cancers: Status, Opportunities, and Challenges

Selective accumulation of a photosensitizer and the subsequent response in only the light-irradiated target are advantages of photodynamic diagnosis and therapy. The limited depth of the therapeutic effect is a positive characteristic when treating surface malignancies, such as peritoneal carcinomatosis. For photodynamic diagnosis (PDD), adjunctive use of aminolevulinic acid- protoporphyrin IX-guided fluorescence imaging detects cancer nodules, which would have been missed during assessment using white light visualization only. Furthermore, since few side effects have been reported, this has the potential to become a vital component of diagnostic laparoscopy. A variety of photosensitizers have been examined for photodynamic therapy (PDT), and treatment protocols are heterogeneous in terms of photosensitizer type and dose, photosensitizer-light time interval, and light source wavelength, dose, and dose rate. Although several studies have suggested that PDT has favorable effects in peritoneal carcinomatosis, clinical trials in more homogenous patient groups are required to identify the true benefits. In addition, major complications, such as bowel perforation and capillary leak syndrome, need to be reduced. In the long term, PDD and PDT are likely to be successful therapeutic options for patients with peritoneal carcinomatosis, with several options to optimize the photosensitizer and light delivery parameters to improve safety and efficacy.

Peritoneal cancer index (PCI) based patient selecting strategy for complete cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy in gastric cancer with peritoneal metastasis: A single-center retrospective analysis of 125 patients

OBJECTIVE

The role of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in gastric cancer with peritoneal metastasis (GCPM) is still controversial, mainly due to the limited survival benefit and uncertain patient selection. This study aims to construct a selecting strategy in GCPM for CRS + HIPEC.

METHODS

From a prospective established database, 125 patients were enrolled. All these patients were pathologically confirmed as GCPM and treated with CRS + HIPEC with or without preoperative or postoperative chemotherapy. The clinical documents and follow-up results were collected and analyzed with the primary endpoint of overall survival (OS) and the secondary endpoint of perioperative serious adverse events (SAEs).

RESULTS

The median OS of 125 GCPM patients treated with CRS + HIPEC was 10.7 months, with 1-, 2-, 3-, and 5-year survival rates of 43.8%, 24.7%, 18.6%, and 15.7%, respectively. The multivariate analysis identified completeness of cytoreduction (CC), SAEs, HIPEC drugs, and adjuvant chemotherapy as independent prognostic factors on OS. The median OS was 30.0 (95%CI: 16.8-43.3) months in CC-0 group, significantly better than 7.3 (95%CI: 5.8-8.8) months in CC1-3 group (P < 0.001). The median OS showed no significant difference among CC-1 (8.5, 95%CI: 6.7-10.2, months), CC-2 (5.6, 95%CI: 3.0-8.2, months) and CC-3 (6.5, 95%CI: 5.2-7.7, months) groups (P > 0.05 for all pairwise comparations). The nomogram based on peritoneal metastasis timing, preoperative tumor marker (TM), and peritoneal cancer index (PCI), with AUC of 0.985, showed a good accuracy and consistency between actual observation and prediction of the probability of complete CRS. The cutoffs of PCI were 16 for synchronous GCPM with normal TM, 12 for synchronous GCPM with abnormal TM, 10 for metachronous GCPM with normal TM, and 5 for metachronous GCPM with abnormal TM, setting the probability to achieve complete CRS as 50%.

CONCLUSIONS

Only complete CRS + HIPEC (CC-0) could improve survival for high selected GCPM patients with acceptable safety. An incomplete CRS (CC1-3) should be avoided for GCPM patients. Synchronous GCPM with PCI ≤16 and normal TM, synchronous GCPM with PCI ≤12 and abnormal TM, metachronous GCPM with PCI ≤10 and normal TM, or metachronous GCPM with PCI ≤5 and abnormal TM maybe potential indications for complete CRS + HIPEC treatment.

Safety and Efficacy of Indocyanine Green Tracer-Guided Lymph Node Dissection During Laparoscopic Radical Gastrectomy in Patients With Gastric Cancer: A Randomized Clinical Trial

Importance

The application of indocyanine green (ICG) imaging in laparoscopic radical gastrectomy is in the preliminary stages of clinical practice, and its safety and efficacy remain controversial.

Objective

To investigate the safety and efficacy of ICG near-infrared tracer-guided imaging during laparoscopic D2 lymphadenectomy in patients with gastric cancer.

Design, Setting, and Participants

Patients with potentially resectable gastric adenocarcinoma (clinical tumor stage cT1-cT4a, N0/+, M0) were enrolled in a prospective randomized clinical trial at a tertiary referral teaching hospital between November 2018 and July 2019. Patients were randomly assigned to the ICG group or the non-ICG group. The number of retrieved lymph nodes, rate of lymph node noncompliance, and postoperative recovery data were compared between the groups in a modified intention-to-treat analysis. Statistical analysis was performed from August to September 2019.

Interventions

The ICG group underwent laparoscopic gastrectomy using near-infrared imaging after receiving an endoscopic peritumoral injection of ICG to the submucosa 1 day before surgery.

Main Outcomes and Measures

Total number of retrieved lymph nodes.

Results

Of 266 participants randomized, 133 underwent ICG tracer-guided laparoscopic gastrectomy, and 133 underwent conventional laparoscopic gastrectomy. After postsurgical exclusions, 258 patients were included in the modified intention-to-treat analysis, which comprised 129 patients (86 men and 43 women; mean [SD] age, 57.8 [10.7] years) in the ICG group and 129 patients (87 men and 42 women; mean [SD] age, 60.1 [9.1] years) in the non-ICG group. The mean number of lymph nodes retrieved in the ICG group was significantly more than the mean number retrieved in the non-ICG group (mean [SD], 50.5 [15.9] lymph nodes vs 42.0 [10.3] lymph nodes, respectively; P < .001). Significantly more perigastric and extraperigastric lymph nodes were retrieved in the ICG group than in the non-ICG group. In addition, the mean total number of lymph nodes retrieved in the ICG group within the scope of D2 lymphadenectomy was also significantly greater than the mean number retrieved in the non-ICG group (mean [SD], 49.6 [15.0] lymph nodes vs 41.7 [10.2] lymph nodes, respectively; P < .001). The lymph node noncompliance rate of the ICG group (41 of 129 patients [31.8%]) was lower than that of the non-ICG group (74 of 129 patients [57.4%]; P < .001). The postoperative recovery process was comparable, and no significant difference was found between the ICG and non-ICG groups in the incidence (20 of 129 patients [15.5%] vs 21 of 129 [16.3%], respectively; P = .86) or severity of complications within 30 days after surgery.

Conclusions and Relevance

Indocyanine green can noticeably improve the number of lymph node dissections and reduce lymph node noncompliance without increased complications in patients undergoing D2 lymphadenectomy. Indocyanine green fluorescence imaging can be performed for routine lymphatic mapping during laparoscopic gastrectomy, especially total gastrectomy.

Trial Registration

ClinicalTrials.gov Identifier: NCT03050879.

The role of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in the treatment of peritoneal carcinomatosis: a systematic review including evidence from Japan

The prognosis of peritoneal carcinomatosis is poor. However, the emergence of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) as a treatment option has prolonged survival and it can even potentially cure patients with peritoneal carcinomatosis. Randomized controlled studies and other observational studies indicated that this combined therapy potentially improved the prognosis of patients with colon, gastric, and ovarian cancers with acceptable morbidity and mortality rates. Even in rarer diseases, such as pseudomyxoma peritonei and malignant peritoneal mesothelioma, CRS + HIPEC markedly improved the prognoses over those with conventional treatment. Based on the accumulated evidence, clinical guidelines recommend CRS + HIPEC for selected patients with peritoneal carcinomatosis. However, several issues still need to be overcome. A standard method for HIPEC has not yet been established. Furthermore, the criteria employed for patient selection need to be clarified to achieve real benefits. The peritoneal cancer index, chemo-sensitivity and several biological markers are considered to be key factors.

An Intraoperative Model for Predicting Survival and Deciding Therapeutic Schedules: A Comprehensive Analysis of Peritoneal Metastasis in Patients With Advanced Gastric Cancer

Background and Objective: No specialized prognostic model for patients with gastric cancer with peritoneal metastasis (GCPM) exists for intraoperative clinical decision making. This study aims to establish a new prognostic model to provide individual treatment decisions for patients with GCPM.

Method: This retrospective analysis included 324 patients with GCPM diagnosed pathologically by laparoscopy from January 2007 to January 2018 who were randomly assigned to different sets (227 in the training set and 97 in the internal validation set). A nomogram was established from preoperative and intraoperative variables determined by a Cox model. The predictive ability and clinical applicability of the PM nomogram (PMN) were compared with the 15th Japanese Classification of Gastric Carcinoma (JCGC) Staging Guidelines for PM (P1abc). Additional external validation was performed using a dataset (n = 39) from the First Affiliated Hospital of University of Science and Technology of China.

Results: The median survival time was 8 (range, 1–90) months. In the training set, each PMN substage had significantly different survival curves (P < 0.001), and the PMN was superior to the P1abc based on the results of time-dependent receiver operating characteristic curve, C-index, Akaike information criterion and likelihood ratio chi-square analyses. In the internal and external validation sets, the PMN was also better than the P1abc in terms of its predictive ability. Of the PMN1 patients, those undergoing palliative resection had better overall survival (OS) than those undergoing exploratory surgery (P < 0.05). Among the patients undergoing exploratory surgery, those who received chemotherapy exhibited better OS than those who did not (P < 0.05). Among the patients who received palliative resection, only PMN1 patients exhibited better OS following chemotherapy (P < 0.05).

Conclusion: We developed and validated a simple, specific PM model for patients with GCPM that can predict prognosis well and guide treatment decisions.

Current Opinion on Peritoneal Carcinomatosis Treatment: a Survey of the Indian Society of Peritoneal Surface Malignancies (ISPSM)

Purpose

Patients with peritoneal carcinomatosis (PC) are increasingly treated with multidisciplinary combined approaches. The study aim was to assess current practice and perceptions of treatment modalities of PC.

Methods

Indian Society of Peritoneal Surface Malignancies (ISPSM) members were invited to complete an online survey. Current practice and perceptions of treatment modalities were assessed through 19 closed questions. Scores were assessed using a Likert scale (0: not important, 5: very important). Treatment modality satisfaction was assessed using a semantic scale (frustrated: 0, perfectly happy: 10). Participants were sent 3 reminders at 4-week intervals.

Results

Fifty-seven out of 182 members completed the survey (31%). Forty percent of participants had an experience of at least 10 years, and 75% stated treating less than 20 PC patients per year. Main treatment goals for patients with PC were cure (5/5) and symptom relief (4/5). Participant’s satisfaction with treatment modalities for ovarian, colorectal, and gastric PC were 6/10, 5/10, and 2/10, respectively. Hyperthermic intraperitoneal chemotherapy (HIPEC) for ovarian (57%) and colorectal (44%) origins were considered to be useful. Clinical usefulness of chemotherapy for gastric PC was rated to be low (17%).

Conclusions

Current treatment modalities fall short to satisfy the needs (cure, symptom relief) of patients with PC. Alternative systemic and intraperitoneal treatment modalities should be assessed.

Electronic supplementary material

The online version of this article (10.1007/s12029-020-00538-1) contains supplementary material, which is available to authorized users.

Established fibrous peritoneal metastasis in an immunocompetent mouse model similar to clinical immune microenvironment of gastric cancer

Background

Peritoneal metastasis (PM) in gastric cancer (GC) is characterized by diffusely infiltrating and proliferating cancer cells accompanied by extensive stromal fibrosis in the peritoneal space. The prognosis of GC with PM is still poor regardless of the various current treatments. In order to elucidate the cause of difficulties in PM treatment, we compared the tumor immune microenvironment (TME) in primary and PM lesions in GC. In addition, a PM model with fibrous stroma was constructed using immunocompetent mice to determine whether its TME was similar to that in patients.

Methods

Immuno-histochemical analyses of infiltrating immune cells were performed in paired primary and PM lesions from 28 patients with GC. A C57BL/6 J mouse model with PM was established using the mouse GC cell line YTN16 either with or without co-inoculation of mouse myofibroblast cell line LmcMF with α-SMA expression. The resected PM from each mouse model was analyzed the immunocompetent cells using immunohistochemistry.

Results

The number of CD8⁺ cells was significantly lower in PM lesions than in primary lesions (P < 0.01). Conversely, the number of CD163⁺ cells (M2 macrophages) was significantly higher in PM lesions than in primary lesions (P = 0.016). Azan staining revealed that YTN16 and LmcMF co-inoculated tumors were more fibrous than tumor with YTN16 alone (P < 0.05). Co-inoculated fibrous tumor also showed an invasive growth pattern and higher progression than tumor with YTN16 alone (P = 0.045). Additionally, YTN16 and LmcMF co-inoculated tumors showed lower infiltration of CD8⁺ cells and higher infiltration of M2 macrophages than tumors with YTN16 alone (P < 0.05, P < 0.05). These results indicate that LmcMF plays as cancer-associated fibroblasts (CAFs) by crosstalk with YTN16 and CAFs contribute tumor progression, invasion, fibrosis, and immune suppression.

Conclusions

This model is the first immunocompetent mouse model similar to TME of human clinical PM with fibrosis. By using this model, new treatment strategies for PM, such as anti-CAFs therapies, may be developed.

Recurrent gastric cancer sustaining a partial response after the nivolumab discontinuation because of immune-related adverse events: a case report

Background

The prognosis of patients with recurrent gastric cancer is poor despite chemotherapy being clinically recommended as the first therapeutic strategy. Recent clinical trials have established the clinical utility of nivolumab in the third-line treatment of such patients. Immune-related adverse events (irAE) have been focused as a promising predictor for tumor response to nivolumab. This report aims to present a long-term survivor of recurrent gastric cancer who was followed up without any treatments after the nivolumab discontinuation because of irAE.

Case presentation

A 65-year-old male with stage III gastric cancer (cT4aN1M0) underwent surgery after neoadjuvant chemotherapy. Owing to the final pathological stage IIIB (ypT4bN1M0), the patient received adjuvant chemotherapy. Nevertheless, during adjuvant chemotherapy 1-year post-surgery, computed tomography (CT) revealed lymph node swelling in station no. 9. Thus, upon diagnosis with lymph node recurrence, the patient was treated with two courses of capecitabine + oxaliplatin and three courses of ramucirumab + paclitaxel as the first- and second-line regimens, respectively. Based on these regimens, the patient had a progressive disease to chemotherapy. Consequently, we administered nivolumab as the third-line regimen. After four courses of nivolumab, CT revealed a significant shrinkage of the metastatic lymph node, with a 45.6% reduction. We confirmed a partial response during 11 courses of nivolumab. Since the occurrence of grade 4 diabetes mellitus after 12 courses of nivolumab, the patient was followed up without any treatment after the nivolumab discontinuation. Currently, the patient remains a partial response for 15 months, since the nivolumab discontinuation and is alive for 31 months after disease recurrence.

Conclusions

Acute irAE during nivolumab chemotherapy could be one of the crucial clinical factors to predict tumor suppression in patients with advanced gastric cancer.

HIPEC plus EPIC paclitaxel for maximal perioperative treatments of advanced epithelial ovarian cancer. Long-term results of a pilot study

BACKGROUND

A unique time in which to effectively treat an intraabdominal malignancy is the time at which the surgeon attempts complete removal of the malignant process. Although surgery is effective for visible disease, micrometastases or multiple small cancer nodules are not amenable to resection. Alternative interventions to deal with residual disease disseminated on peritoneal surfaces are needed.

MATERIALS AND METHODS

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) can be combined with early postoperative intraperitoneal chemotherapy (EPIC) in order to maximally treat gross disease within the abdomen and pelvis and also the minimal residual disease that exists in many patients after resection. The third component of this treatment for ovarian malignancy was EPIC paclitaxel in this study. The clinical features, pharmacologic assessments, and survival were determined in ovarian cancer patients in whom EPIC was added to the perioperative treatment plan.

RESULTS

Patients with high grade serous ovarian cancer underwent CRS, HIPEC with cisplatin/doxorubicin, and EPIC paclitaxel. These treatments combined as a single intervention were studied in 10 patients. The median number of peritonectomy procedures was 1, the median number of visceral resections was 5, and the median time required in the operating room was 8 h. Two patients had a class 3 adverse event. The median survival of patients was 50 months. Pharmacokinetic analysis of the intraperitoneal paclitaxel showed 252 ± 153 times exposure of peritoneal surfaces as compared to intravenous exposure when the drug was instilled into the peritoneal space.

CONCLUSIONS

EPIC paclitaxel was successfully combined with CRS and HIPEC in 10 patients with ovarian cancer. The treatment was tolerated approximately the same as other major cytoreductive surgical procedures for ovarian cancer or other malignancies. Survival of these ovarian cancer patients seemed unusually prolonged as compared to other patients with stage 3b or recurrent disease. In this pilot study CRS, HIPEC and EPIC were safe and effective.

Prognostic value of CEA/CA72-4 immunohistochemistry in combination with cytology for detecting tumor cells in peritoneal lavage in gastric cancer

Aim: To study the value and efficiency of CEA/CA72-4 immunohistochemistry in detecting free tumor cells from peritoneal lavage, in order to provide reliable lab information for subsequent intraperitoneal chemotherapy. Methods: A total of 112 progressive gastric cancer patients were enrolled from Oct. 2016 to Oct 2017, who were pathologically diagnosed as gastric cancer after surgery. Peritoneal lavage was respectively collected during operation. Cytology and CEA/CA72-4 immunohistochemistry of peritoneal lavage samples was performed. Overall survival and recurrence free survival was analyzed. Results: Cytology showed 16 positive cases (14.29%), CEA immunohistochemistry showed 29 positive cases (25.89%), CA72-4 immunohistochemistry showed 33 positive cases (29.46%). McNemar's test showed significant difference in positivity between cytology (CY+) and CEA/CA72-4 immunohistochemistry (IHC+). Kappa test showed consistency between immunohistochemistry of CEA and CA72-4 with cytology. Patients with CY+/IHC+ had the poorest overall survival (OS) as well as recurrence free survival (RFS), followed by those with CY+ or IHC+, while those with CY-/IHC- had higher OS and RFS. The differences of OS and RFS in IHC+ group were worse than that in IHC- group. Kaplan-Meier analysis showed that positive CEA/CA72-4 IHC revealed poorer prognosis than the negative cases. Conclusions: Due to the limitation of cytology, combination of cytology and immunohistochemistry appears to be more efficient for predicting prognosis of progressive gastric cancer.

Efficacy of intraperitoneally administered paclitaxel for colorectal cancer with peritoneal metastases

PURPOSE

Prognosis after peritoneal metastases in colorectal cancer is worse than that after lung or liver metastases. Previously, we demonstrated the safety of intraperitoneal (ip) administration of paclitaxel (PTX) combined with mFOLFOX6/CapeOX plus bevacizumab for colorectal cancer with peritoneal metastasis in a phase-I trial. Here, we evaluated the efficacy of this chemotherapy.

METHODS

We enrolled six patients with histologically confirmed peritoneal metastases secondary to colorectal cancer. PTX was administered through a peritoneal access port, in combination with oxaliplatin-based systematic chemotherapy. Response rate, progression-free survival, 1-year survival rate, frequency of improvement in peritoneal cancer index (PCI), and cytology in peritoneal lavage were evaluated. This study was registered in the University Hospital Medical Information Network Clinical Trial Registry on July 1, 2016 (UNIN000022924).

RESULTS

Three patients received the mFOLFOX6-bevacizumab regimen, whereas the other three received the CapeOX-bevacizumab regimen. The response rate was 25%. PCI score improved in 50% of the cases. Peritoneal lavage cytology that was positive in five patients before initiating the chemotherapy turned negative during chemotherapy in all patients. One-year survival rate was 100%, progression-free survival was 8.8 months (range, 6.8-12 months), and median survival time was 29.3 months.

CONCLUSION

The ip administration of PTX with systemic chemotherapy can potentially control peritoneal metastases in colorectal cancer.

A Case of Peritoneal Dissemination and Splenic Metastasis after Gastric Cancer Surgery That Could Be Controlled with Multidisciplinary Treatment

Splenic metastasis is known to occur at the terminal stage of cancer. While peritoneal dissemination is the most frequent recurrence of gastric cancer, metastasis to the spleen from gastric cancer is very rare. Splenectomy is currently the most effective probable treatment for solitary splenic metastasis of gastric cancer; it provides a good patient prognosis. However, careful consideration of surgical indications is required, as splenic metastasis is typically accompanied by multi-organ metastasis and dissemination. One of the main cancer treatment methods is the “wait-and-see” approach using chemotherapy. In general, patients with gastric cancer are treated with systemic chemotherapy for distant metastases including peritoneal dissemination. Radiotherapy is not commonly used to prolong life in patients with gastric cancer as gastric cancer is predominantly adenocarcinoma. However, a recent report indicated that chemo-radiotherapy was performed successfully for unresectable gastric cancer, including peritoneal dissemination. Here, we present the case of a 67-year-old patient who was observed to have peritoneal dissemination and splenic metastasis after gastric cancer surgery. Once the peritoneal dissemination was localized, surgical excision and chemo-radiotherapy were performed. We treated the splenic metastasis with the “wait-and-see” strategy with chemotherapy. A complete response on imaging in accordance with the Response Evaluation Criteria in Solid Tumors was achieved using multidisciplinary treatment. Our strategy of intensive multidisciplinary therapy could be a treatment option for cases with peritoneal dissemination or splenic metastasis of gastric cancer.

Clinical outcomes of capecitabine-based versus S-1-based regimens as first-line chemotherapy in patients with unresectable or metastatic gastric cancer: a propensity score matched single-center comparison

Background

Fluoropyrimidine-based regimens are the cornerstone of first-line chemotherapy for metastatic gastric cancer (GC). Capecitabine or S-1 might be used as an alternative to infusional 5-fluorouracil, especially in pan-Asian. This study aimed to compare the clinical outcomes of capecitabine-based and S-1-based regimens as first-line chemotherapy in Chinese patients with unresectable or metastatic GC.

Methods

We conducted a retrospective study including unresectable or metastatic GC patients treated with the capecitabine-based or S-1-based regimen as first-line chemotherapy at the First Hospital of China Medical University. Propensity score matching (PSM) analysis was performed to reduce selection bias. Overall survival (OS) outcomes were compared using the Kaplan-Meier method and log-rank test. Prognostic significance was determined using multivariate Cox regression analysis. In addition, subgroup analyses were conducted to determine the effectiveness of capecitabine-based and S-1-based regimens in clinically relevant patient subsets.

Results

The clinical data of 469 patients included between October 2005 and September 2018. PSM analysis identified 187 patients receiving capecitabine-based or S-1-based regimen. No significant difference in OS (10.7 vs. 11.1 months, P=0.523) was detected between the two groups after PSM. In the subgroup analysis, the median OS (12.2 vs. 9.3 months, P=0.013) was longer for patients with peritoneum metastasis who received the capecitabine-based regimen compared to those who received the S-1-based regimen.

Conclusions

No significant difference in clinical outcomes was observed between the capecitabine and S-1-based regimen as first-line chemotherapy for metastatic or unresectable GC patients in China. The capecitabine-based regimen should be considered in the treatment of the GC patients with peritoneum metastasis.

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.