Intraperitoneal chemotherapy for gastric cancer with peritoneal metastasis

Preoperative assessment and prognostic prediction of gastric cancer patients with peritoneal metastasis using 18F-FDG PET/CT before conversion surgery

BACKGROUND

Conversion therapy followed by conversion surgery (CS) can improve the prognosis of gastric cancer (GC) patients with peritoneal metastasis (PM). However, patients benefit differently. There is no way to confirm the prognostic benefit non-invasively and early. This retrospective study assessed the value of 18F-FDG PET/CT after conversion therapy in preoperative assessment and prognostic prediction of GC patients with PM.

RESULTS

Fifty-one GC patients with PM were enrolled. 18F-FDG PET/CT after conversion therapy helped in preoperative assessment. Its diagnostic accuracy for residual peritoneal lesions was slightly better than contrast-enhanced CT (72.5% vs. 61.2%, P = 0.229), although the difference was not statistically significant. TBR of peritoneal lesions could help preoperative assessment, with TBR of peritoneal lesions to the mediastinal blood pool SUVmax (TBRAmaxp) as the best predictor (cutoff = 0.705, specificity 80%, sensitivity 80%, AUC 0.825, P < 0.001). Additionally, PET/CT could predict prognosis and assess surgical benefit. SUVmax of peritoneal lesions (SUVmaxp) was the best predictor of 24 months survival (cutoff = 1.466, AUC 0.870, P = 0.002, Specificity 77.8%, Sensitivity 83.3%) and metabolic parameters of peritoneal lesions could predict OS and the prognosis of patients who underwent CS.

CONCLUSION

18F-FDG PET/CT provides quantitative imaging indicators for preoperative evaluation and prognostic prediction in GC patients with PM.

Dual responsive drug-loaded nanomotor based on zwitterionic materials for the treatment of peritoneal metastatic cancer

Innovative treatments for peritoneal metastatic cancer have attracted widespread attention from researchers. Here, we propose a drug-loaded nanomotor (PSBMA/l-Arg/DOX, PLD) based on zwitterionic materials for the treatment of peritoneal metastatic cancer through intraperitoneal injection. Zwitterionic polymer nanocarriers (PSBMA NPs) are obtained by radical polymerization with zwitterionic SBMA as the polymerization monomer and N,N'-Bis(acryloyl)cystamine (BAC) as the cross-linking agent. The zwitterionic substrate of this nanomotor has the ability to resist non-specific protein adsorption in ascites. The loaded l-arginine enables the nanomotor to have the ability to chemotaxis towards high concentrations of ROS/iNOS in tumors and be catalyzed to produce NO, achieving deep penetration into tumor tissue. Furthermore, the disulfide bond (SS) carried by the crosslinking agent used in the preparation of the nanomotor can respond to the high expression of reducing glutathione in the tumor microenvironment and undergo degradation, releasing a large amount of loaded drug DOX. Cell and animal disease model experiments confirme the good therapeutic effect of this drug-loaded nanomotor, providing new therapeutic concepts and strategies for the treatment of peritoneal metastatic cancer.

Treatment of Gastric Cancer Carcinomatosis

Patients with gastric cancer peritoneal metastases (GCPM) have Stage IV disease. Systemic therapy is a crucial aspect of their care. Patients with GCPM should have their tumors tested for HER2 and PD-L1 expression and microsatellite instability for potential targeted therapies. If patients with synchronous GCPM have stable disease following neoadjuvant therapy, surgical intervention can be considered. Patients with positive cytology or low-volume peritoneal disease (peritoneal carcinomatosis index [PCI] < 7) may "convert" to negative cytology or resolution of peritoneal metastases following intraperitoneal therapy and may be candidates for subsequent gastrectomy.

Lidocaine Enhanced Antitumor Efficacy and Relieved Chemotherapy-Induced Hyperalgesia in Mice with Metastatic Gastric Cancer

With the widespread use of lidocaine for pain control in cancer therapy, its antitumor activity has attracted considerable attention in recent years. This paper provides a simple strategy of combining lidocaine with chemotherapy drugs for cancer therapy, aiming to relieve chemotherapy-induced pain and achieve stronger antitumor efficacy. However, there is still a lack of substantial pre-clinical evidence for the efficacy and related mechanisms of such combinations, obstructing their potential clinical application. In this study, we propose intraperitoneal chemotherapy (IPC) against gastric cancer (GC) as an ideal scenario to evaluate the efficacy of a lidocaine/paclitaxel combination. Firstly, we used human GC cells MKN-45-luc to investigate the antitumor activity and related mechanisms of the lidocaine/paclitaxel combination in vitro. Then, we used C57BL/6 mice with intraperitoneal drug suffusion to evaluate the efficacy of lidocaine to suppress paclitaxel-induced hyperalgesia and related mechanisms. Lastly, in BALB/c tumor-bearing nude mice we evaluated the synergistic antitumor activity and pain-relieving effect of the lidocaine/paclitaxel combination. Our results showed enhanced antitumor activity for the lidocaine/paclitaxel combination, which induced apoptosis, inhibited migration, and the invasion of GC cells in a synergistic manner. In animal models, the lidocaine/paclitaxel combination effectively inhibited growth and peritoneal metastasis of the tumor, resulting in prolonged survival time. Meanwhile, lidocaine showed considerable anti-inflammatory activity alongside its anesthetic effect, which, in combination, effectively relieved hyperalgesia induced by paclitaxel. These results suggested that intraperitoneal suffusion with lidocaine/paclitaxel could be a pain-free IPC formulation with enhanced antitumor activity, which could provide a promising treatment for GC with peritoneal metastasis.

Efficacy analysis of prophylactic hyperthermic intraperitoneal chemotherapy in patients with locally advanced gastric cancer: a retrospective study

Purpose

This study aims to evaluate the effectiveness and safety of prophylactic hyperthermic intraperitoneal chemotherapy (P-HIPEC) in patients with locally advanced gastric cancer (AGC) after laparoscopic radical gastrectomy. Additionally, it explores how the frequency and timing of P-HIPEC influence treatment outcomes.

Methods

A retrospective analysis was conducted on 227 patients with locally AGC who underwent laparoscopic surgery at Maoming People's Hospital from January 2016 to December 2022. Patients were stratified into the HIPEC group (n=101) and the non-HIPEC group (n=126), based on whether they received postoperative P-HIPEC. Propensity score matching (PSM) was used to adjust for baseline characteristics, facilitating a comparative analysis of survival outcomes, postoperative complications and recurrence patterns. Cox regression analysis was performed to identify prognostic factors. Furthermore, the impact of varying P-HIPEC frequencies and initiation timings was evaluated.

Results

No significant differences in overall survival (OS) or postoperative complication rates were observed between the two groups in the original and PSM cohorts. But the disease-free survival (DFS) of the HIPEC group was significantly higher than that of the non-HIPEC group (HR 0.569; 95% CI 0.362-0.894; p = 0.013) in the PSM cohort, with 1-year, 3-year, and 5-year DFS rates showing notable improvement (77.9% vs. 69.7%, 60.1% vs. 43.0%, and 46.2% vs. 25.5%). The incidence of isolated peritoneal metastasis (PM) was significantly lower in the HIPEC group (5.3% vs. 17.3%, p = 0.039). Multivariate Cox regression analysis identified P-HIPEC as an independent protective factor for DFS. Further analysis indicated that neither the number of P-HIPEC sessions had a significant impact on OS (p = 0.388) or DFS (p = 0.735), nor did the timing of P-HIPEC initiation affect OS (p = 0.620) or DFS (p = 0.488). Likewise, different P-HIPEC frequencies or initiation timings had no significant impact on postoperative complication rates or recurrence patterns.

Conclusion

P-HIPEC effectively reduces the risk of postoperative PM and improves DFS in patients with locally AGC without increasing postoperative complications. However, it does not significantly impact OS. Additionally, variations in the frequency and timing of P-HIPEC initiation do not significantly affect survival outcomes, postoperative complications, or recurrence patterns.

A comprehensive overview of gastric cancer management from a surgical point of view

Despite advancements in medical care, surgical technologies, and the development of novel treatments over the past decade, the prognosis for patients with gastric cancer (GC) has only modestly improved. This is primarily due to the fact that the majority of patients are diagnosed at advanced stages or present with metastatic disease. Radical resection remains the cornerstone of potentially curative treatment, yet the overall 5-year survival rate remains below 35%. The management of GC varies globally, influenced by factors such as geographical disparities, patient comorbidities and performance status, surgical approaches, and available medical resources. Multidisciplinary collaboration and a multimodal treatment approach are essential for optimizing patient outcomes. Surgeons must stay updated on emerging surgical concepts and make informed decisions regarding patient selection, timing of intervention, and the adoption of appropriate surgical techniques to improve both quality of life and prognosis. This review aims to provide a surgical perspective on the management of GC across all stages, highlighting the importance of a comprehensive treatment approach. Endoscopic resection may be a viable option for early GC in patients with minimal risk of lymph node metastasis, particularly in elderly patients with high surgical risk or severe comorbidities. For advanced GC, neoadjuvant therapy followed by surgery could be a promising strategy to improve patient outcomes. Conversion surgery offers a potential survival benefit for patients who respond to treatment with tumor downstaging. The treatment of peritoneal carcinomatosis remains challenging; however, hyperthermic intraperitoneal chemotherapy combined with complete cytoreductive surgery or pressurized intraperitoneal aerosolized chemotherapy may prolong survival or improve quality of life in highly selected patients.

Important Predictive Factors for the Prognosis of Patients With Peritoneal Metastasis of Gastric Cancer

BACKGROUND

This study investigated predictive factors for patients with peritoneal metastases of gastric cancer (PMGC) who underwent conversion cytoreductive surgery (C-CRS) and hyperthermic intraperitoneal intraoperative chemotherapy (HIPEC) after responding to induction chemotherapy (laparoscopic HIPEC [LHIPEC]) followed by concomitant systemic and intraperitoneal chemotherapy (bidirectional intraperitoneal and systemic chemotherapy [BIC]).

METHODS

Diagnostic laparoscopy was performed for 62 patients with PMGC between January 2017 and December 2022. The patients underwent LHIPEC and BIC induction chemotherapy using intraperitoneal docetaxel (30 mg/m2) and cisplatin (30 mg/m2), and intravenous chemotherapy for three cycles. The predictive parameters for progression-free and overall survival were analyzed using Kaplan-Meier and Cox regression analyses. The optimal cutoff values for Ki-67 parameters were assessed using receiver operating characteristic curve analysis.

RESULTS

The study retrospectively examined 36 (58 %) of 62 patients who responded to induction therapy and underwent C-CRS or HIPEC. A Ki-67 index lower than 10 (p = 0.000), lymph node involvement (LNI) less than 2 (p = 0.039), and an omental lesion size score lower than 0.5 cm (p = 0.002) were predictive of recurrence-free and overall survival in addition to completeness of cytoreduction and the peritoneal cancer index. Cox regression analysis showed that the independent factors associated with recurrence-free survival were decreased Ki-67 expression (≥10 % vs <10 %) (hazard ratio [HR] 4.7; 95 % confidence interval [CI] 1.6-5.210; p = 0.020) and LNI higher than 2 (HR 1.92; 95% CIS 0.923-4.0; p = 0.023).

CONCLUSIONS

Lymph node involvement and decreased Ki-67 expression are independent predictive factors of recurrence-free survival for patients with PMGC after induction chemotherapy.

Efficacy of Hyperthermic Pressurized Intraperitoneal Aerosol Chemotherapy in an In Vitro Model Using a Human Gastric Cancer AGS Cell Line and an Abdominal Cavity Model

PURPOSE

Peritoneal carcinomatosis (PC) presents a major challenge in the treatment of late-stage, solid tumors, with traditional therapies limited by poor drug penetration. We evaluated a novel hyperthermic pressurized intraperitoneal aerosol chemotherapy (HPIPAC) system using a human abdominal cavity model for its efficacy against AGS gastric cancer cells.

MATERIALS AND METHODS

A model simulating the human abdominal cavity and AGS gastric cancer cell line cultured dishes were used to assess the efficacy of the HPIPAC system. Cell viability was measured to evaluate the impact of HPIPAC under 6 different conditions: heat alone, PIPAC with paclitaxel (PTX), PTX alone, normal saline (NS) alone, heat with NS, and HPIPAC with PTX.

RESULTS

Results showed a significant reduction in cell viability with HPIPAC combined with PTX, indicating enhanced cytotoxic effects. Immediately after treatment, the average cell viability was 66.6%, which decreased to 49.2% after 48 hours and to a further 19.6% after 120 hours of incubation, demonstrating the sustained efficacy of the treatment. In contrast, control groups exhibited a recovery in cell viability; heat alone showed cell viability increasing from 90.8% to 94.4%, PIPAC with PTX from 82.7% to 89.7%, PTX only from 73.3% to 74.8%, NS only from 90.9% to 98.3%, and heat with NS from 74.4% to 84.7%.

CONCLUSIONS

The HPIPAC system with PTX exhibits a promising approach in the treatment of PC in gastric cancer, significantly reducing cell viability. Despite certain limitations, this study highlights the system's potential to enhance treatment outcomes. Future efforts should focus on refining HPIPAC and validating its effectiveness in clinical settings.

Prognostic Relevance of Recurrent Sites of Gastric Cancer Treated With Curative Resection: A Single Center Retrospective Study

PURPOSE

Gastric cancer treated with curative resection exhibits several recurrence patterns. The peritoneum is the most common site of recurrence. Some reports have indicated different prognostic influences according to the recurrence sites in other cancers, such as esophageal and colorectal cancers. This study investigated whether the recurrence sites influenced the prognosis of patients with recurrent gastric cancer.

MATERIALS AND METHODS

The data of 115 patients who experienced tumor recurrence after curative gastrectomy were retrospectively reviewed. The sites of recurrence were divided into 4 groups: lymph node (LN), peritoneum, other single organs, and multiple lesions. Clinicopathological features were compared between the sites of recurrence. Prognosis after resection and recurrence were also compared.

RESULTS

The peritoneum was the primary site of recurrence in 38 patients (33%). The tumor differentiation and pathological stages were significantly different. Survival after surgery did not show a statistically significant difference (hazard ratio [HR] of LN: 1, peritoneum: 1.083, other single organs: 1.025, and multiple lesions: 1.058; P=1.00). Survival after recurrence was significantly different (HR of LN, 1; peritoneum, 2.164; other single organs, 1.092; multiple lesions, 1.554; P=0.01), and patients with peritoneal and multiple lesion recurrences had worse prognosis. Furthermore, peritoneal recurrence seemed to occur later than that at other sites; the median times to recurrence in LN, peritoneal, other single-organ, and multiple lesions were 265, 722, 372, and 325 days, respectively.

CONCLUSIONS

The sites of gastric cancer recurrence may have different prognostic effects. Peritoneal recurrence may be less sensitive to chemotherapy and occur during the late phase of recurrence.

Population pharmacokinetics of intraperitoneal irinotecan and SN-38 in patients with peritoneal metastases from colorectal origin

Peritoneal metastases (PM) are common in patients with colorectal cancer. Patients with PM have a poor prognosis, and for those who are not eligible for cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC), palliative chemotherapy is currently the only option. Recently, we conducted a phase I trial (INTERACT) in which irinotecan was administered intraperitoneally (IP) to 18 patients ineligible for CRS-HIPEC. The primary objective was to evaluate covariates influencing the PK profile of irinotecan and SN-38 after IP administration. Secondly, a population PK model was developed to support the further development of IP irinotecan by improving dosing in patients with PM. Patients were treated with IP irinotecan every 2 weeks in combination with systemic FOLFOX-bevacizumab. Irinotecan and SN-38 were measured in plasma (588 samples) and SN-38 was measured in peritoneal fluid (267 samples). Concentration-Time data were log-transformed and analyzed using NONMEM version 7.5 using FOCE+I estimation. An additive error model described the residual error, with inter-individual variability in PK parameters modeled exponentially. The final structural model consisted of five compartments. Weight was identified as a covariate influencing the SN-38 plasma volume of distribution and GGT was found to influence the SN-38 plasma clearance. This population PK model adequately described the irinotecan and SN-38 in plasma after IP administration, with weight and GGT as predictive factors. Irinotecan is converted intraperitoneal to SN-38 by carboxylesterases and the plasma bioavailability of irinotecan is low. This model will be used for the further clinical development of IP irinotecan by providing dosing strategies.

Hyperthermic pressurized intraperitoneal aerosol drug delivery system in a large animal model: a feasibility and safety study

BACKGROUND

We developed a novel drug delivery system called hyperthermic pressurized intraperitoneal aerosol chemotherapy (HPIPAC) that hybridized Hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC). The present study aims to assess the feasibility and safety of HPIPAC system in a large animal survival model.

METHODS

Eleven pigs (eight non-survival models and three survival models) were used in the experiment. The heat module in the HPIPAC controller circulates hyperthermic CO2 in a closed-loop circuit and creates gas-based dry intraperitoneal hyperthermia. Three 12 mm trocars were placed on the abdomen. The afferent CO2 tube wound with heat generating coil was inserted into a trocar, and the efferent tube was inserted into another trocar. Heated CO2 was insufflated and circulated in a closed circuit until the intra-abdominal and peritoneal surface temperature reached 42 °C. 100 ml of 5% dextrose in water was nebulized for 5 min and the closed-loop circulation was resumed for 60 min at 42 °C. Tissue biopsies were taken from several sites from the pigs in the survival model.

RESULTS

The average change in core temperature of the pigs was 2.5 ± 0.08 °C. All three pigs displayed no signs of distress, and their vital signs remained stable, with no changes in their diet. In autopsy, inflammatory and fibrotic responses at the biopsy sites were observed without serious pathologic findings.

CONCLUSIONS

We successfully proved the feasibility and safety of our novel HPIPAC system in an in-vivo swine survival model.

Phase II Study of Intraperitoneal Administration of Paclitaxel Combined with S-1 and Cisplatin for Gastric Cancer with Peritoneal Metastasis

BACKGROUND

Intraperitoneal chemotherapy is promising for gastric cancer with peritoneal metastasis. Although a phase III study failed to show a statistically significant superiority of intraperitoneal paclitaxel combined with S-1 and intravenous paclitaxel, the sensitivity analysis suggested clinical efficacy. Thus, attempts to combine intraperitoneal paclitaxel with other systemic therapies with higher efficacy have been warranted. We sought to explore the efficacy of intraperitoneal paclitaxel with S-1 and cisplatin.

PATIENTS AND METHODS

Gastric cancer patients with peritoneal metastasis were enrolled in the phase II trial. In addition to the established S-1 and cisplatin regimen every 5 weeks, intraperitoneal paclitaxel was administered on days 1, 8, and 22 at a dose of 20 mg/m2. The primary endpoint was overall survival rate at 1 year after treatment initiation. Secondary endpoints were progression-free survival and toxicity.

RESULTS

Fifty-three patients were enrolled and fully evaluated for efficacy and toxicity. The 1-year overall survival rate was 73.6% (95% confidence interval 59.5-83.4%), and the primary endpoint was met. The median survival time was 19.4 months (95% confidence interval, 16.1-24.6 months). The 1-year progression-free survival rate was 49.6% (95% confidence interval, 34.6-62.9%). The incidences of grade 3/4 hematological and non-hematological toxicities were 43% and 47%, respectively. The frequent grade 3/4 toxicities included neutropenia (25%), anemia (30%), diarrhea (13%), and anorexia (17%). Intraperitoneal catheter and implanted port-related complications were observed in four patients. There was one treatment-related death.

CONCLUSIONS

Intraperitoneal paclitaxel combined with S-1 and cisplatin is well tolerated and active in gastric cancer patients with peritoneal metastasis.

Progress in the Treatment of Peritoneal Metastatic Cancer and the Application of Therapeutic Nanoagents

Peritoneal metastatic cancer is a cancer caused by the direct growth of cancer cells from the primary site through the bloodstream, lymph, or peritoneum, which is a difficult part of current clinical treatment. In the abdominal cavity of patients with metastatic peritoneal cancer, there are usually nodules of various sizes and malignant ascites. Among them, nodules of different sizes can obstruct intestinal movement and form intestinal obstruction, while malignant ascites can cause abdominal distension and discomfort, and even cause patients to have difficulty in breathing. The pathology and physiology of peritoneal metastatic cancer are complex and not fully understood. The main hypothesis is "seed" and "soil"; i.e., cells from the primary tumor are shed and implanted in the peritoneal cavity (peritoneal metastasis). In the last two decades, the main treatment modalities used clinically are cytoreductive surgery (CRS), systemic chemotherapy, intraperitoneal chemotherapy, and combined treatment, all of which help to improve patient survival and quality of life (QOL). However, the small-molecule chemotherapeutic drugs used clinically still have problems such as rapid drug metabolism and systemic toxicity. With the rapid development of nanotechnology in recent years, therapeutic nanoagents for the treatment of peritoneal metastatic cancer have been gradually developed, which has improved the therapeutic effect and reduced the systemic toxicity of small-molecule chemotherapeutic drugs to a certain extent. In addition, nanomaterials have been developed not only as therapeutic agents but also as imaging agents to guide peritoneal tumor CRS. In this review, we describe the etiology and pathological features of peritoneal metastatic cancer, discuss in detail the clinical treatments that have been used for peritoneal metastatic cancer, and analyze the advantages and disadvantages of the different clinical treatments and the QOL of the treated patients, followed by a discussion focusing on the progress, obstacles, and challenges in the use of therapeutic nanoagents in peritoneal metastatic cancer. Finally, therapeutic nanoagents and therapeutic tools that may be used in the future for the treatment of peritoneal metastatic cancer are prospected.

Prognostic Analysis of Prophylactic Hyperthermic Intraperitoneal Chemotherapy for Advanced Gastric Cancer: a Propensity Score-Matched Analysis

PURPOSE

To investigate the efficacy of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) for advanced gastric cancer (AGC).

METHODS

We included 198 patients treated from December 2016 to January 2019; of these patients, the 132 who had clinical T4 gastric cancer were divided into a hyperthermic intraperitoneal chemotherapy group (HIPEC group) and a radical gastrectomy and D2 lymph node dissection group (control group). Because this study was retrospective, we used propensity score matching (PSM) to reduce selectivity bias; we then assessed risk factors for recurrence and compared prognosis in terms of survival in the gastrectomy and prophylactic HIPEC groups.

RESULTS

Prophylactic HIPEC reduced the risk of postoperative peritoneal metastasis (PM: 27.5% vs. 10.5%, P = 0.015) and did not increase the risk of postoperative complications, but there was no significant difference in the effect on hepatic metastases or other distant metastases. Risk factors for recurrence included pT4 staging and positive lymph node metastases. Both disease-free survival (DFS: HR 0.592; 95% CI 0.354-0.990; P = 0.042) and peritoneal recurrence-free survival (PFS: HR 0.314; 95% CI 0.127-0.774; P = 0.008) were better in the prophylactic HIPEC group than in the gastrectomy-only group. In addition, there was no difference in the prognosis of patients between the two groups of raltitrexed (RT) and paclitaxel (PTX) for perfusion dosing.

CONCLUSION

Our study showed that prophylactic HIPEC could prevent postoperative PM in patients with AGC and did not increase the incidence of postoperative complications. However, it was not found to be effective in the prevention of other metastases, such as hepatic metastases.

Phase I study of intraperitoneal irinotecan combined with palliative systemic chemotherapy in patients with colorectal peritoneal metastases

BACKGROUND

Patients with colorectal peritoneal metastases who are not eligible for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) owing to extensive peritoneal disease have a poor prognosis. It was hypothesized that these patients may benefit from the addition of intraperitoneal irinotecan to standard palliative systemic chemotherapy.

METHODS

This was a classical 3 + 3 phase I dose-escalation trial in patients with colorectal peritoneal metastases who were not eligible for CRS-HIPEC. Intraperitoneal irinotecan was administered every 2 weeks, concomitantly with systemic FOLFOX (5-fluorouracil, folinic acid, oxaliplatin)-bevacizumab. The primary objective was to determine the maximum tolerated dose and dose-limiting toxicities. Secondary objectives were to elucidate the systemic and intraperitoneal pharmacokinetics, safety profile, and efficacy.

RESULTS

Eighteen patients were treated. No dose-limiting toxicities were observed with 50 mg (4 patients) and 75 mg (9 patients) intraperitoneal irinotecan. Two dose-limiting toxicities occurred with 100 mg irinotecan among five patients. The maximum tolerated dose of intraperitoneal irinotecan was established to be 75 mg, and it was well tolerated. Intraperitoneal exposure to SN-38 (active metabolite of irinotecan) was high compared with systemic exposure (median intraperitoneal area under the curve (AUC) to systemic AUC ratio 4.6). Thirteen patients had a partial radiological response and five had stable disease. Four patients showed a complete response during post-treatment diagnostic laparoscopy. Five patients underwent salvage resection or CRS-HIPEC. Median overall survival was 23.9 months.

CONCLUSION

Administration of 75 mg intraperitoneal irinotecan concomitantly with systemic FOLFOX-bevacizumab was safe and well tolerated. Intraperitoneal SN-38 exposure was high and prolonged. As oncological outcomes were promising, intraperitoneal administration of irinotecan may be a good alternative to other, more invasive and costly treatment options. A phase II study is currently accruing.

Clinical significance of intraperitoneal paclitaxel combined with systemic chemotherapy for gastric cancer with peritoneal metastasis

BACKGROUND

Despite investigations of intraperitoneal paclitaxel as a personalized treatment for peritoneal metastasis of gastric cancer, few studies have evaluated its prognostic impact on conversion surgery for unresectable gastric cancer with peritoneal metastasis. Our study aimed to close this gap in knowledge.

METHODS

We retrospectively enrolled 128 patients who underwent chemotherapy for peritoneal metastasis from gastric cancer and assigned them into intraperitoneal (IP) (n = 36) and non-IP (n = 92) groups, based on the use of intraperitoneal paclitaxel plus systemic chemotherapy.

RESULTS

Disease control rates were 94% and 69% in the IP and non-IP groups, respectively, with the former having a significantly higher tumor response rate than the latter (p < 0.01). The median survival times in the IP and non-IP groups were 665 and 359 days, respectively, with the former having significantly better prognosis than the latter (p = 0.02). Fifteen (42%) and sixteen (17%) patients underwent conversion surgery after chemotherapy in the IP and non-IP groups, respectively, with the former having a significantly higher conversion surgery induction rate than the latter (p < 0.01). Although the prognosis of the conversion surgery group was significantly better than that of the non-conversion surgery group (p < 0.01), there was no significant difference in prognosis between patients in the IP and non-IP groups who underwent conversion surgery (p = 0.22). Multivariate analysis identified performance status and conversion surgery as independent prognostic factors (all p < 0.01).

CONCLUSION

Our study demonstrated that the IP chemotherapy was one of important factors for conversion surgery induction, while it was not a risk factor for prognosis.

Efficacy evaluation of chimeric antigen receptor-modified human peritoneal macrophages in the treatment of gastric cancer

BACKGROUND

Gastric cancer is one of the most common cancers. Peritoneal carcinomatosis (PC) appears to be the most common pattern of recurrence, and more than half of the GC patients eventually die from PC. Novel strategies for the management of patients with PC are urgently needed. Recently, rapid progress has been made in adoptive transfer therapy by using macrophages as the effector cells due to their capabilities of phagocytosis, antigen presentation, and high penetration. Here, we generated a novel macrophage-based therapy and investigated anti-tumoral effects on GC and potential toxicity.

METHODS

We developed a novel Chimeric Antigen Receptor-Macrophage (CAR-M) based on genetically modifying human peritoneal macrophages (PMs), expressing a HER2-FcεR1γ-CAR (HF-CAR). We tested HF-CAR macrophages in a variety of GC models in vitro and in vivo.

RESULTS

HF-CAR-PMs specifically targeted HER2-expressed GC, and harboured the FcεR1γ moieties to trigger engulfment. Intraperitoneal administration of HF-CAR-PMs significantly facilitated the HER2-positive tumour regression in PC mouse model and prolonged the overall survival rate. In addition, the combined use of oxaliplatin and HF-CAR-PMs exhibited significantly augment anti-tumour activity and survival benefit.

CONCLUSIONS

HF-CAR-PMs could represent an exciting therapeutic option for patients with HER2-positive GC cancer, which should be tested in carefully designed clinical trials.

INTRAPERITONEAL CHEMOTHERAPY FOR GASTRIC CANCER WITH PERITONEAL CARCINOMATOSIS: STUDY PROTOCOL OF A PHASE II TRIAL

BACKGROUND

Peritoneal carcinomatosis in gastric cancer is considered a fatal disease, without expectation of definitive cure. As systemic chemotherapy is not sufficient to contain the disease, a multimodal approach associating intraperitoneal chemotherapy with surgery may represent an alternative for these cases.

AIMS

The aim of this study was to investigate the role of intraperitoneal chemotherapy in stage IV gastric cancer patients with peritoneal metastasis.

METHODS

This study is a single institutional single-arm prospective clinical trial phase II (NCT05541146). Patients with the following inclusion criteria undergo implantation of a peritoneal catheter for intraperitoneal chemotherapy: Stage IV gastric adenocarcinoma; age 18-75 years; Peritoneal carcinomatosis with peritoneal cancer index<12; Eastern Cooperative Oncology Group 0/1; good clinical status; and lab exams within normal limits. The study protocol consists of four cycles of intraperitoneal chemotherapy with paclitaxel associated with systemic chemotherapy. After treatment, patients with peritoneal response assessed by staging laparoscopy undergo conversion gastrectomy.

RESULTS

The primary outcome is the rate of complete peritoneal response. Progression-free and overall survivals are other outcomes evaluated. The study started in July 2022, and patients will be screened for inclusion until 30 are enrolled.

CONCLUSIONS

Therapies for advanced gastric cancer patients have been evaluated in clinical trials but without success in patients with peritoneal metastasis. The treatment proposed in this trial can be promising, with easy catheter implantation and ambulatory intraperitoneal chemotherapy regime. Verifying the efficacy and safety of paclitaxel with systemic chemotherapy is an important progress that this study intends to investigate.

Epithelial SOX9 drives progression and metastases of gastric adenocarcinoma by promoting immunosuppressive tumour microenvironment

OBJECTIVE

Many cancers engage embryonic genes for rapid growth and evading the immune system. SOX9 has been upregulated in many tumours, yet the role of SOX9 in mediating immunosuppressive tumour microenvironment is unclear. Here, we aim to dissect the role of SOX9-mediated cancer stemness attributes and immunosuppressive microenvironment in advanced gastric adenocarcinoma (GAC) for novel therapeutic discoveries.

METHODS

Bulk RNAseq/scRNA-seq, patient-derived cells/models and extensive functional studies were used to identify the expression and functions of SOX9 and its target genes in vitro and in vivo. Immune responses were studied in PBMCs or CD45⁺ immune cells cocultured with tumour cells with SOX9^high or knockout and the KP-Luc2 syngeneic models were used for efficacy of combinations.

RESULTS

SOX9 is one of the most upregulated SOX genes in GAC and highly expressed in primary and metastatic tissues and associated with poor prognosis. Depletion of SOX9 in patient-derived GAC cells significantly decreased cancer stemness attributes, tumour formation and metastases and consistently increased CD8⁺ T cell responses when cocultured with PBMCs/CD45⁺ cells from GAC patients. RNA sequencing identified the leukaemia inhibitory factor (LIF) as the top secreted molecule regulated by SOX9 in tumour cells and was enriched in malignant ascites and mediated SOX9-induced M2 macrophage repolarisation and inhibited T cell function.

CONCLUSION

Epithelial SOX9 is critical in suppressing CD8⁺ T cell responses and modified macrophage function in GAC through the paracrine LIF factor. Cotargeting LIF/LIFR and CSF1R has great potential in targeting SOX9-mediated cancer stemness, T cell immunosuppression and metastases suggesting the novel combination therapy against advanced GAC.

Survival and complications of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy in patients with intra-abdominal malignancies: A meta-analysis of randomized controlled trials

Background: Peritoneal metastasis (PM) is an advanced stage of intra-abdominal malignancy with a very poor prognosis. In recent years, hyperthermic intraperitoneal chemotherapy (HIPEC) combined with cytoreductive surgery (CRS) has been utilized as an active treatment in the prevention and treatment of PM, with encouraging results. However, compared with CRS alone, the results of the CRS plus HIPEC strategy in the treatment of patients with intra-abdominal malignancies are still controversial. This study sought to determine the impact of HIPEC + CRS on patient survival and adverse events (AEs) by reviewing randomized controlled trials (RCTs) for all types of intra-abdominal malignancies.

Methods: A PubMed, Embase, Cochrane Library, Web of Science and Clinical Trials.gov search extracted all RCTs until 12 October 2022, examining the CRS + HIPEC vs. CRS alone strategies in the treatment of various types of intra-abdominal malignancies. The outcomes included overall survival (OS), disease-free survival (DFS), relapse-free survival (RFS), progression-free survival (PFS) and AEs. The dichotomous data were pooled and reported as odds ratios (ORs) with 95% confidence intervals (CIs). The survival outcome data were pooled using hazard ratios (HRs) and corresponding 95% CIs. The Cochrane Collaboration’s Risk of Bias Tool was used to assess the risk of bias in the included studies.

Results: A total of 12 RCTs were included in this meta-analysis, including 873 patients in the CRS + HIPEC group and 878 patients in the CRS alone group. The studies included 3 (617 patients) on colorectal cancer, 4 (416 patients) on gastric cancer, and 5 (718 patients) on ovarian cancer. Our analysis showed no difference in OS between the CRS + HIPEC and CRS alone groups (HR: 0.79, 95% CI 0.62–1.01). Subgroup analysis showed that CRS + HIPEC improved the OS of gastric cancer patients (HR: 0.49, 95% CI 0.32–0.76) compared with CRS alone. However, CRS + HIPEC did not significantly improve the OS of colorectal cancer (HR: 1.06, 95% CI 0.81–1.38) and ovarian cancer (HR: 0.82, 95% CI 0.62–1.07) patients. In addition, there was no significant difference in DFS/RFS (HR: 0.78, 95% CI 0.57–1.07) or PFS (HR: 1.03, 95% CI 0.77–1.38) between the two groups. Compared with CRS alone, CRS with HIPEC had greater nephrotoxicity (OR: 0.45, 95% CI 0.21–0.98), while other AEs did not differ significantly between the two groups.

Conclusion: Our results suggest that CRS + HIPEC may improve OS in gastric cancer patients compared with CRS alone, but we did not observe a benefit for DFS/RFS. For patients with ovarian and colorectal cancers, our results suggest that HIPEC + CRS does not appear to improve survival outcomes. In addition, CRS + HIPEC has higher nephrotoxicity than CRS alone. More evidence from RCTs is needed to evaluate whether the use of CRS + HIPEC is an appropriate option.

Intraperitoneal Chemotherapy for Unresectable Peritoneal Surface Malignancies

Malignancies of the peritoneal cavity are associated with a dismal prognosis. Systemic chemotherapy is the gold standard for patients with unresectable peritoneal disease, but its intraperitoneal effect is hampered by the peritoneal-plasma barrier. Intraperitoneal chemotherapy, which is administered repeatedly into the peritoneal cavity through a peritoneal implanted port, could provide a novel treatment modality for this patient population. This review provides a systematic overview of intraperitoneal used drugs, the performed clinical studies so far, and the complications of the peritoneal implemental ports. Several anticancer drugs have been studied for intraperitoneal application, with the taxanes paclitaxel and docetaxel as the most commonly used drug. Repeated intraperitoneal chemotherapy, mostly in combination with systemic chemotherapy, has shown promising results in Phase I and Phase II studies for several tumor types, such as gastric cancer, ovarian cancer, colorectal cancer, and pancreatic cancer. Two Phase III studies for intraperitoneal chemotherapy in gastric cancer have been performed so far, but the results regarding the superiority over standard systemic chemotherapy alone, are contradictory. Pressurized intraperitoneal administration, known as PIPAC, is an alternative way of administering intraperitoneal chemotherapy, and the first prospective studies have shown a tolerable safety profile. Although intraperitoneal chemotherapy might be a standard treatment option for patients with unresectable peritoneal disease, more Phase II and Phase III studies focusing on tolerability profiles, survival rates, and quality of life are warranted in order to establish optimal treatment schedules and to establish a potential role for intraperitoneal chemotherapy in the approach to unresectable peritoneal disease.

Integration of Genomic Biology Into Therapeutic Strategies of Gastric Cancer Peritoneal Metastasis

The peritoneum is a common site of metastasis in advanced gastric cancer (GC). Diagnostic laparoscopy is now routinely performed as part of disease staging, leading to an earlier diagnosis of synchronous peritoneal metastasis (PM). The biology of GCPM is unique and aggressive, leading to a dismal prognosis. These tumors tend to be resistant to traditional systemic therapy, and yet, this remains the current standard-of-care recommended by most international clinical guidelines. As this is an area of unmet clinical need, several translational studies and clinical trials have focused on addressing this specific disease state. Advances in genomic sequencing and molecular profiling have revealed several promising therapeutic targets and elucidated novel biology, particularly on the role of the surrounding tumor microenvironment in GCPM. Peritoneal-specific clinical trials are being designed with a combination of locoregional therapeutic strategies with systemic therapy. In this review, we summarize the new knowledge of cancer biology, advances in surgical techniques, and emergence of novel therapies as an integrated strategy emerges to address GCPM as a distinct clinical entity.

Phase 1 trial of intraperitoneal paclitaxel in combination with intravenous cisplatin and oral capecitabine in patients with advanced gastric cancer and peritoneal metastases (IPGP study)

AIMS

Gastric cancer with peritoneal involvement has a poor prognosis. Intraperitoneal (IP) paclitaxel has shown promising results in these patients. However, this approach has only been studied in the Asian population, and in combination with S-1. We investigated the maximum tolerated dose of IP paclitaxel, with a standard chemotherapy combination, in the Australian population.

METHODS

The study of the population included metastatic human epidermal growth factor receptor 2 (HER2) negative gastric adenocarcinoma with peritoneal involvement. Treatment included six 21-day cycles of cisplatin (80 mg/m2 IV, day 1) plus capecitabine (1000 mg/m2 PO BD, days 1-14) plus IP paclitaxel (days 1 and 8). IP paclitaxel doses for cohort 1-3 were 10, 20, and 30 mg/m2 , respectively, in a 3 + 3 standard dose-escalation design.

RESULTS

Fifteen patients were enrolled of which 6 were female and the median age was 63. Two patients developed dose-limiting toxicities. No grade 4/5 toxicities were recorded. The maximum tolerated dose was not reached. Therefore, as defined by the study protocol, the recommended phase-2 dose for IP paclitaxel was determined to be 30 mg/m2 . The 12-month survival rate was 46.7%, and the median survival was 11.5 months (interquartile range [IQR]: 15.3-6.9).

CONCLUSIONS

IP paclitaxel is safe in combination with cisplatin and capecitabine and the recommended phase-2 dose is 30 mg/m2 .

Tumor-Promoting ATAD2 and Its Preclinical Challenges

ATAD2 has received extensive attention in recent years as one prospective oncogene with tumor-promoting features in many malignancies. ATAD2 is a highly conserved bromodomain family protein that exerts its biological functions by mainly AAA ATPase and bromodomain. ATAD2 acts as an epigenetic decoder and transcription factor or co-activator, which is engaged in cellular activities, such as transcriptional regulation, DNA replication, and protein modification. ATAD2 has been reported to be highly expressed in a variety of human malignancies, including gastrointestinal malignancies, reproductive malignancies, urological malignancies, lung cancer, and other types of malignancies. ATAD2 is involved in the activation of multiple oncogenic signaling pathways and is closely associated with tumorigenesis, progression, chemoresistance, and poor prognosis, but the oncogenic mechanisms vary in different cancer types. Moreover, the direct targeting of ATAD2’s bromodomain may be a very challenging task. In this review, we summarized the role of ATAD2 in various types of malignancies and pointed out the pharmacological direction.

Safety and Efficacy of Intraperitoneal Paclitaxel Plus Intravenous Fluorouracil, Leucovorin, and Oxaliplatin (FOLFOX) for Gastric Cancer with Peritoneal Metastasis

BACKGROUND

Peritoneal metastasis (PM) remains a major obstacle in the treatment of stage IV gastric cancer. This is a dose-escalation study of intraperitoneal (IP) paclitaxel combined with intravenous (IV) fluorouracil, leucovorin, and oxaliplatin (FOLFOX) to determine the recommended phase II dose in gastric cancer patients.

METHODS

Patients with gastric adenocarcinoma and PM were enrolled. The recommended phase II dose of IP paclitaxel was determined using the standard "3 + 3" dose escalation with planned doses ranging from 40 to 100 mg/m². IV FOLFOX was administered on the same day (oxaliplatin 100 mg/m² (day 1), leucovorin 100 mg/m² (day 1), fluorouracil 2,400 mg/m² over 46 hours (day 1)). Both IP and IV regimens were repeated every 2 weeks.

RESULTS

Among the 13 patients, there was no DLT at 40 and 60 mg/m². Two patients had grade 3 febrile neutropenia at 80 mg/m², and the recommended phase II dose was 60 mg/m². Other patients underwent IP paclitaxel and FOLFOX without serious adverse events. Seven patients underwent second-look diagnostic laparoscopy, and the average change in PCI score was -7.0 ± 9.7. Conversion surgery rate was 23.1% (n = 3). The median overall survival was 16.6 months (95% confidence interval, 16.6-N/A), and progression-free survival was 9.6 months (95% confidence interval, 4.7-N/A). All adverse events were tolerable and manageable.

CONCLUSIONS

The biweekly regimen of IP paclitaxel and FOLFOX is safe and the recommended dose of IP paclitaxel for a phase II trial is 60 mg/m².

Nanotherapeutic macrophage-based immunotherapy for the peritoneal carcinomatosis of lung cancer

Lung cancer is the top cause of cancer mortality in the world. Distant metastasis leads to high mortality. Abdominal metastasis of lung cancer is characterized by very poor prognosis and the median survival time is usually less than two months. Therefore, it is of clinical significance to develop a new effective method for the treatment of abdominal metastasis of lung cancer. Cell therapy has promoted the development of new technology and strategy in oncology. Macrophages, as an important component of solid tumors, have also attracted great attention as a promising strategy of cell therapy in oncology. However, the reinfusion of autologous macrophages would be easily "re-educated" by the tumor microenvironment into a phenotype that promotes tumor development. This work developed a potential therapy using celastrol nanoparticle-containing M1-like macrophages (NP@M1) as a combinatory therapeutic system. M1-like macrophages (M1Φ) not only can serve as a drug delivery carrier for celastrol but also as a biotherapeutic agent. In turn, the celastrol nanoparticles (NPs) can maintain an anticancer polarized status of M1Φ, and subsequently, the exocytosed NPs can also execute the tumor cell-killing effect. Such a system thus provides a "two-birds-one-stone" therapeutic strategy and a proof of concept for the currently incurable abdominal metastasis of lung cancer.

Review of Regional Therapies for Gastric Cancer with Peritoneal Metastases

Simple Summary

Gastric cancer is usually diagnosed at late stages and is associated with poor five-year survival rates. Metastasis to the peritoneal cavity is common and leads to even worse outcomes. Currently, the mainstay of treatment for metastatic gastric cancer is systemic chemotherapy or supportive care. These recommendations remain despite evidence that suggests systemic therapy has poor penetration into the abdominal cavity, limiting efficacy against peritoneal disease. Newer treatments have been developed to address this problem, specifically regional therapies aimed at delivering chemotherapy directly into the peritoneal cavity to eradicate tumor cells. These novel therapies include hyperthermic intraperitoneal chemotherapy, normothermic intraperitoneal chemotherapy, and pressurized intraperitoneal aerosolized chemotherapy. Regional therapies may also be combined with surgery to remove both macroscopic and microscopic disease. Although more clinical trials are needed to evaluate its efficacy, early studies have shown promising outcomes with intraperitoneal chemotherapy.

Abstract

Gastric cancer carries a poor prognosis and is a leading cause of cancer-related mortality worldwide. Patients with gastric cancer who develop peritoneal metastases have an even more dismal prognosis, with median survival time measured in months. Since studies have demonstrated that systemic chemotherapy has poor penetration into the peritoneum, multimodal treatment with intraperitoneal chemotherapy has been proposed for the treatment of peritoneal metastases and has become the foundation for newer therapeutic techniques and clinical trials. These include heated intraperitoneal chemotherapy (HIPEC) with cytoreductive surgery (CRS), which involves the application of heated chemotherapy into the abdomen with or without tumor debulking surgery; normothermic intraperitoneal chemotherapy (NIPEC), in which non-heated chemotherapy can be delivered into the abdomen via a peritoneal port allowing for repeat dosing; and pressurized intraperitoneal aerosolized chemotherapy (PIPAC), a newer technique of pressurized and aerosolized chemotherapy delivered into the abdomen during laparoscopy. Early results with intraperitoneal chemotherapy have shown promise in increasing disease-free and overall survival in select patients. Additionally, there may be a palliative effect of these regional therapies. In this review, we explore and summarize these different intraperitoneal chemotherapy treatment regimens for gastric cancer with peritoneal metastases.

I.p.-injected cationic liposomes are retained and accumulate in peritoneally disseminated tumors

Intraperitoneal (i.p) chemotherapy is an attractive approach to treat peritoneally disseminated cancers by delivering therapeutic agents directly to the peritoneal cavity where some disseminated tumors are located. Cationic liposomes (CLs) have been used as a viable delivery carrier for i.p. chemotherapy to improve the peritoneal retention of anticancer agents. However, there are no reports on the fate of CLs following i.p. administration to the peritoneal cavity in the presence of disseminated tumors. We prepared a tumor xenograft murine model of peritoneally disseminated gastric cancer by i.p. inoculation of human gastric cancer cells and followed the fate of either CLs or PEGylated CLs (PEG-CLs) after i.p. injection in the model. I.p.-injected CLs were retained in peritoneal cavity for at least 3 days post-injection as a result of clustering with ascites fluid proteins, mainly albumin, while i.p. PEG-CLs was rapidly cleared from the peritoneal cavity to the circulation within 3 h post-injection. Importantly, i.p. CLs efficiently accumulated in the targeted disseminated tumor cells, but not in other abdominal organs including liver, spleen, and kidney. The tumor selectivity upon i.p. administration of CLs may be associated with the lymphatic drainage system. A lipoplex formulation composed of CLs with short hairpin RNA (shRNA) against luciferase, a model therapeutic agent, suppressed luciferase activity in peritoneally disseminated tumors by 80%, with no cytokine secretion in serum. This suggests that i.p. CLs can efficiently deliver a therapeutic agent to peritoneally disseminated tumors with few systemic adverse events. These results suggest that i.p. treatment with CLs or non-PEGylated lipoplexes may be a promising approach for the treatment of peritoneally disseminated cancers through their ability to selectively deliver therapeutic agents to i.p. target sites with minimal systemic adverse events.

Synergism of rMV-Hu191 with cisplatin to treat gastric cancer by acid sphingomyelinase-mediated apoptosis requiring integrity of lipid raft microdomains

BACKGROUND

DDP-based chemotherapy is one of the first-line treatment in GC. However, the therapeutic efficacy of DDP is limited due to side effects. Therefore, it is of great significance to develop novel adjuvants to synergize with DDP. We had demonstrated previously that rMV-Hu191 had antitumor activity in GC. Here we examined the synergism of rMV-Hu191 with DDP in vitro and in vivo.

METHODS

Cellular proliferation, the synergistic effect and cell apoptosis were evaluated by CCK-8 assay, ZIP analysis and flow cytometry, respectively. The protein levels and location of ASMase were monitored by western blot and immunofluorescence assay. shRNA and imipramine were used to regulate the expression and activity of ASMase. MβCD was administrated to disrupt lipid rafts. Mice bearing GC xenografts were used to confirm the synergism in vivo.

RESULTS

From our data, combinational therapy demonstrated synergistic cytotoxicity both in resistant GC cell lines from a Chinese patient and drug-nonresistant GC cell lines, and increased cell apoptosis, instead of viral replication. Integrity of lipid rafts and ASMase were required for rMV-Hu191- and combination-induced apoptosis. The ASMase was delivered to the lipid raft microdomains at the initial stage of rMV-Hu191 treatment. In vivo GC mice xenografts confirmed the synergism of combinational treatment, together with increased apoptosis and trivial side-effects.

CONCLUSIONS

This is the first study to demonstrate that rMV-Hu191 combined with DDP could be used as a potential therapeutic strategy in GC treatment and the ASMase and the integrity of lipid rafts are required for the synergistic effects.

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

OBJECTIVE

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

SUMMARY BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Polydatin, a Glycoside of Resveratrol, Induces Apoptosis and Inhibits Metastasis Oral Squamous Cell Carcinoma Cells In Vitro

Although various methods, such as surgery and chemotherapy, are applied to the treatment of OSCC, there are problems, such as functional and aesthetic limitations of the mouth and face, drug side effects, and lymph node metastasis. Many researchers are making efforts to develop new therapeutic agents from plant-derived substances to overcome the side effects that occur in oral cancer treatment. Polydatin is known as a natural precursor of resveratrol, and research on its efficacy is being actively conducted recently. Therefore, we investigated whether polydatin can induce apoptosis and whether it affects cell migration and invasion through the regulation of EMT-related factors in OSCC. Polydatin decreased the survival and proliferation rates of CAL27 and Ca9-22 cells, and induced the release of cytochrome c, a factor related to apoptosis, and fragmentation of procaspase-3 and PARP. Another form of cell death, autophagy, was observed in polydatin-treated cells. In addition, polydatin inhibits cell migration and invasion, and it has been shown to occur through increased expression of E-cadherin, an EMT related factor, and decreased expression of N-cadherin and Slug and Snail proteins and genes. These findings suggest that polydatin is a potential oral cancer treatment.

Apolipoprotein C-II induces EMT to promote gastric cancer peritoneal metastasis via PI3K/AKT/mTOR pathway

BACKGROUND

Peritoneal metastasis (PM) occurs frequently in patients with gastric cancer (GC) and confers poor survival. Lipid metabolism acts as a non-negligible regulator in epithelial-mesenchymal transition (EMT), which is crucial for the metastasis of GC. As apolipoprotein C2 (APOC2) is a key activator of lipoprotein lipase for triglyceride metabolism, the exact mechanism of APOC2 remains largely unknown in GC.

METHODS

Tandem mass tags identified differentially expressed proteins between human PM and GC tissues, and showed that APOC2 overexpressed in PM tissues, which was further confirmed by immunoblotting, immunohistochemistry, and ELISA. Global gene expression changes were identified in APOC2 knockdown cells via RNA-sequencing. The role of APOC2 in lipid metabolism of GC cells was assessed via the Seahorse XF analyzer and lipid staining assays. The biological role of APOC2 in GC cells was determined by 3D Spheroid invasion, apoptosis, colony formation, wound healing, transwell assay, and mouse models. The interaction between APOC2 and CD36 was analyzed by co-immunoprecipitation and biolayer interferometry. The underlying mechanisms were investigated using western blot technique.

RESULTS

APOC2 overexpressed in GC PM tissues. Upregulation of APOC2 correlated with a poor prognosis in GC patients. APOC2 promoted GC cell invasion, migration, and proliferation via CD36-mediated PI3K/AKT/mTOR signaling activation. Furthermore, APOC2-CD36 axis upregulated EMT markers of GC cells via increasing the phosphorylation of PI3K, AKT, and mTOR. Knockdown either APOC2 or CD36 inhibited the malignant phenotype of cancer cells, and delayed GC PM progression in murine GC models.

CONCLUSION

APOC2 cooperates with CD36 to induce EMT to promote GC PM via PI3K/AKT/mTOR pathway. APOC2-CD36 axis may be a potential target for the treatment of aggressive GC.

Doxorubicin Embedded into Nanofibrillated Bacterial Cellulose (NFBC) Produces a Promising Therapeutic Outcome for Peritoneally Metastatic Gastric Cancer in Mice Models via Intraperitoneal Direct Injection

Natural materials such as bacterial cellulose are gaining interest for their use as drug-delivery vehicles. Herein, the utility of nanofibrillated bacterial cellulose (NFBC), which is produced by culturing a cellulose-producing bacterium (Gluconacetobacter intermedius NEDO-01) in a medium supplemented with carboxymethylcellulose (CMC) that is referred to as CM-NFBC, is described. Recently, we demonstrated that intraperitoneal administration of paclitaxel (PTX)-containing CM-NFBC efficiently suppressed tumor growth in a peritoneally disseminated cancer xenograft model. In this study, to confirm the applicability of NFBC in cancer therapy, a chemotherapeutic agent, doxorubicin (DXR), embedded into CM-NFBC, was examined for its efficiency to treat a peritoneally disseminated gastric cancer via intraperitoneal administration. DXR was efficiently embedded into CM-NFBC (DXR/CM-NFBC). In an in vitro release experiment, 79.5% of DXR was released linearly into the peritoneal wash fluid over a period of 24 h. In the peritoneally disseminated gastric cancer xenograft model, intraperitoneal administration of DXR/CM-NFBC induced superior tumor growth inhibition (TGI = 85.5%) by day 35 post-tumor inoculation, compared to free DXR (TGI = 62.4%). In addition, compared with free DXR, the severe side effects that cause body weight loss were lessened via treatment with DXR/CM-NFBC. These results support the feasibility of CM-NFBC as a drug-delivery vehicle for various anticancer agents. This approach may lead to improved therapeutic outcomes for the treatment of intraperitoneally disseminated cancers.

Hyperthermic Intraperitoneal Chemotherapy: A Critical Review

Simple Summary

Patients with cancer of the digestive system or ovarian cancer are at risk of developing peritoneal metastases (PM). In some patients with PM, surgery followed by intraperitoneal (IP) chemotherapy has emerged as a valid treatment option. The addition of hyperthermia is thought to further enhance the efficacy of IP chemotherapy. However, the results of recent clinical trials in large bowel cancer have put into question the use of hyperthermic intraperitoneal chemotherapy (HIPEC). Here, we review the rationale and current results of HIPEC for PM and propose a roadmap to further progress.

Abstract

With increasing awareness amongst physicians and improved radiological imaging techniques, the peritoneal cavity is increasingly recognized as an important metastatic site in various malignancies. Prognosis of these patients is usually poor as traditional treatment including surgical resection or systemic treatment is relatively ineffective. Intraperitoneal delivery of chemotherapeutic agents is thought to be an attractive alternative as this results in high tumor tissue concentrations with limited systemic exposure. The addition of hyperthermia aims to potentiate the anti-tumor effects of chemotherapy, resulting in the concept of heated intraperitoneal chemotherapy (HIPEC) for the treatment of peritoneal metastases as it was developed about 3 decades ago. With increasing experience, HIPEC has become a safe and accepted treatment offered in many centers around the world. However, standardization of the technique has been poor and results from clinical trials have been equivocal. As a result, the true value of HIPEC in the treatment of peritoneal metastases remains a matter of debate. The current review aims to provide a critical overview of the theoretical concept and preclinical and clinical study results, to outline areas of persisting uncertainty, and to propose a framework to better define the role of HIPEC in the treatment of peritoneal malignancies.

LIMK1 promotes peritoneal metastasis of gastric cancer and is a therapeutic target

Peritoneal metastasis is a common form of metastasis among advanced gastric cancer patients. In this study, we reported the identification of LIM domain kinase 1 (LIMK1) as a promoter of gastric cancer peritoneal metastasis, and its potential to be a therapeutic target of dabrafenib (DAB). Using transcriptomic sequencing of paired gastric cancer peritoneal metastasis, primary tumors, and normal gastric tissues, we first unveiled that LIMK1 is selectively up-regulated in metastatic tumors. Increased LIMK1 in gastric cancer peritoneal metastasis was validated by immunohistochemistry analysis of an independent patient cohort. In vitro functional studies demonstrated that LIMK1 knockout or knockdown significantly inhibited cell migration and invasion of gastric cancer cells. LIMK1 knockout also abrogated peritoneal and liver metastases of gastric cancer cells in nude mice in vivo. Dabrafenib, a small molecule targeting LIMK1, was found to decrease cell migration and invasion of gastric cancer cells in vitro and abolish peritoneal and liver metastasis formation in vivo. Mechanistically, either LIMK1 knockout or Dabrafenib inhibited LIMK1 expression and phosphorylation of its downstream target cofilin. Taken together, our results demonstrated that LIMK1 functions as a metastasis promoter in gastric cancer by inhibiting LIMK1-p-cofilin and that Dabrafenib has the potential to serve as a novel treatment for gastric cancer peritoneal 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 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.

Therapeutic efficacy of a paclitaxel-loaded nanofibrillated bacterial cellulose (PTX/NFBC) formulation in a peritoneally disseminated gastric cancer xenograft model

Nano-fibrillated bacterial cellulose (NFBC) is a safe, biocompatible material that can be prepared by culturing a cellulose-producing bacterium in a culture supplemented with carboxymethylcellulose (CMC) or hydroxypropylcellulose (HPC). CM-NFBC and HP-NFBC, prepared using CMC or HPC, show hydrophilicity and amphiphilicity, respectively, and thus they could be useful carriers for hydrophobic anticancer agents such as paclitaxel (PTX). In the present study, we prepared novel PTX formulations for intraperitoneal administration by associating PTX with either CM-NFBC or HP-NFBC and studied their therapeutic efficacy on peritoneally disseminated gastric cancer in a xenograft nude mouse model. Freeze-dried PTX formulations (PTX/CM-NFBC and PTX/HP-NFBC) were quickly reconstituted with saline without any foaming, compared to nanoparticle albumin-bound PTX (nab-PTX, Abraxane®). Both PTX/NFBC formulations extended the mean survival times in our xenograft murine models compared with either free PTX or nab-PTX. The PTX/NFBC formulations reduced systemic side effects of free PTX relating to weight loss. In our disseminated gastric peritoneal cancer model, the PTX/NFBC formulation increased the therapeutic index for PTX by increasing the therapeutic efficacy and decreasing toxicity. NFBCs should receive consideration as improved carriers for the clinical delivery of hydrophobic anticancer drugs such as PTX in malignancies in the abdominal cavity with peritoneal metastasis and dissemination.

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.

YAP1 mediates gastric adenocarcinoma peritoneal metastases that are attenuated by YAP1 inhibition

OBJECTIVE

Peritoneal carcinomatosis (PC; malignant ascites or implants) occurs in approximately 45% of advanced gastric adenocarcinoma (GAC) patients and associated with a poor survival. The molecular events leading to PC are unknown. The yes-associated protein 1 (YAP1) oncogene has emerged in many tumour types, but its clinical significance in PC is unclear. Here, we investigated the role of YAP1 in PC and its potential as a therapeutic target.

METHODS

Patient-derived PC cells, patient-derived xenograft (PDX) and patient-derived orthotopic (PDO) models were used to study the function of YAP1 in vitro and in vivo. Immunofluorescence and immunohistochemical staining, RNA sequencing (RNA-Seq) and single-cell RNA-Seq (sc-RNA-Seq) were used to elucidate the expression of YAP1 and PC cell heterogeneity. LentiCRISPR/Cas9 knockout of YAP1 and a YAP1 inhibitor were used to dissect its role in PC metastases.

RESULTS

YAP1 was highly upregulated in PC tumour cells, conferred cancer stem cell (CSC) properties and appeared to be a metastatic driver. Dual staining of YAP1/EpCAM and sc-RNA-Seq revealed that PC tumour cells were highly heterogeneous, YAP1^high PC cells had CSC-like properties and easily formed PDX/PDO tumours but also formed PC in mice, while genetic knockout YAP1 significantly slowed tumour growth and eliminated PC in PDO model. Additionally, pharmacologic inhibition of YAP1 specifically reduced CSC-like properties and suppressed tumour growth in YAP1^high PC cells especially in combination with cytotoxics in vivo PDX model.

CONCLUSIONS

YAP1 is essential for PC that is attenuated by YAP1 inhibition. Our data provide a strong rationale to target YAP1 in clinic for GAC patients with PC.

An RNAi therapeutic, DFP-10825, for intraperitoneal and intrapleural malignant cancers

RNA interference (RNAi), a potent post-transcriptional gene-silencing action, has received considerable attentions as a novel therapeutic tool to treat intractable cancers. In recent days, we have developed a novel RNAi-based therapeutic formulation, DFP-10825, for the treatment of intractable advanced cancers developed in coelomic cavities. DFP-10825 was composed of chemically synthesized short hairpin RNA (shRNA) against thymidylate synthase (TS), a key enzyme for cancer proliferation, and cationic liposomes, and achieved high therapeutic effect on the mouse models of peritoneally disseminated gastric and ovarian cancers and malignant pleural mesothelioma without severe side effects by intracoelomic direct treatment. We further designed a freeze-dried DFP-10825 formulation for mass industrial production. DFP-10825 is undergoing in pre-clinical phase and goes to clinical trials. This review introduces a DFP-10825 formulation, a potent novel RNAi-based therapeutic maximizing the benefit of RNAi molecule (shRNA).

Phase I Trial of Hyperthermic Intraperitoneal Chemoperfusion (HIPEC) with Cisplatin, Mitomycin, and Paclitaxel in Patients with Gastric Adenocarcinoma and Associated Carcinomatosis or Positive Cytology

BACKGROUND

The purpose of this phase I trial is to evaluate the safety and toxicity of laparoscopic hyperthermic intraperitoneal perfusion with chemotherapy (HIPEC), combining mitomycin, cisplatin, and paclitaxel for patients with gastric cancer metastatic to the peritoneum.

PATIENTS AND METHODS

A Bayesian optimal interval design was used to prospectively identify the safety and tolerability of escalating doses of paclitaxel in combination with flat doses of mitomycin (30 mg) and cisplatin (200 mg) during laparoscopic HIPEC. The primary objective is to define the maximum tolerated dose. Secondary endpoints include surgical complications and overall survival (OS).

RESULTS

A total of 27 patients were treated between 11/2017 and 11/2018. No dose-limiting toxicities were observed. Treatment-related grade 1-2 toxicities were leukopenia (11%), oral dysesthesia (4%), arthralgia (4%), and diarrhea (4%). Treatment-related grade 3-4 toxicities included leukopenia (4%) and neutropenia (4%). The maximum dose for paclitaxel was 60 mg/m2. Rates of Clavien-Dindo surgical complications were grade I 96% (all electrolyte deficiencies requiring replacement), II 4%, III 0%, IV 0%, and V 4%. The median follow-up time was 15 months. One- and 2-year OS rates from date of metastatic disease were 73.9% and 58.1%, respectively.

CONCLUSIONS

Laparoscopic HIPEC with mitomycin, cisplatin, and paclitaxel may be safely used at intraperitoneal doses of 30 mg, 200 mg, and 60 mg/m2, respectively. Although electrolyte abnormalities were common, systemic toxicity was low. Survival rates were promising, supporting further research into intraperitoneal therapy for stage IV gastric cancer.

Safety, pharmacokinetics and tissue penetration of PIPAC paclitaxel in a swine model

INTRODUCTION

Peritoneal carcinomatosis is difficult to treat. Pressurized Intra-Peritoneal Aerosolised Chemotherapy (PIPAC) is a novel method of delivering chemotherapy to the peritoneal cavity, aiming for homogenous and deeper drug distribution. To date, limited chemotherapeutics have been used with promising results. Here, we evaluate the pharmacokinetics, peritoneal tissue drug concentration, penetration, and short-term safety of PIPAC using solvent-based paclitaxel in swine to guide clinical trials.

MATERIALS AND METHODS

PIPAC solvent-based paclitaxel was administered at 60, 30, and 15mg/m² for 3 cohorts. Each PIPAC procedure was followed by intravenous (IV) administration of the same dose of solvent-based paclitaxel on Day 7, serving as control for pharmacokinetic comparison in the same pig. Safety and toxicity were evaluated by clinical assessment, blood counts and biochemistry. Blood samples were taken for pharmacokinetic analysis. Peritoneal biopsies were taken to measure tissue paclitaxel concentrations and distribution.

RESULTS

12 Yorkshire x Landrace pigs underwent trial procedures. With PIPAC, there was linear pharmacokinetics and lower systemic exposure to paclitaxel compared to IV administration. MALDI-MSI demonstrated concentration of paclitaxel at the peritoneal surface, with estimated 2 mm penetration. PIPAC paclitaxel had favorable toxicity profile. The most significant adverse event was neutropenia which was dose dependent, with absolute neutrophil count <1.0 × 10³/μL seen at the highest dose. One pig developed grade 2 hypersensitivity reaction during IV infusion and one death occurred during the PIPAC procedure, likely from anaphylaxis; these are known potential adverse events mandating standard precautions and monitoring.

CONCLUSION

PIPAC paclitaxel at 15mg/m² may be considered for a Phase I study.

Lobaplatin in Prophylactic Hyperthermic Intraperitoneal Chemotherapy for Advanced Gastric Cancer: Safety and Efficacy Profiles

OBJECTIVE

This study aims to evaluate the safety and efficacy of lobaplatin in prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) for advanced gastric cancer.

METHODS

Advanced gastric cancer patients who underwent radical gastric resection and/or prophylactic HIPEC were systematically reviewed in our department from January 2016 to June 2017. All enrolled patients were grouped in either HIPEC or non-HIPEC groups. Clinical data were collected and analyzed.

RESULTS

A total of 129 patients were enrolled with 61 cases in the HIPEC group and 68 in the non-HIPEC group. The two groups were well balanced in terms of clinical characteristics. In patients of the HIPEC group, three suffered leakage from the duodenal stump or anastomosis, one suffered abnormal bleeding and two were found to have abnormal routine blood tests; no significant difference in adverse events between groups, however, was noted (p > 0.05) and most patients recovered uneventfully. During follow-up, peritoneal recurrence was significantly less among HIPEC patients (p = 0.029), with only three suffering peritoneal recurrence, as compared to 12 non-HIPEC patients. In addition, the estimated illness-specific 3-year disease-free survival rate was significantly higher in the HIPEC group as compared to the non-HIPEC group (89.4% vs.73.9%; p = 0.031).

CONCLUSION

Lobaplatin in prophylactic HIPEC is safe for advanced gastric cancer patients after treatment by radical resection and can effectively improve illness-specific 3-year disease-free survival.

Observational Study of Peritoneal Washing Cytology-Positive Gastric Cancer without Gross Peritoneal Metastasis in Patients who Underwent Radical D2 Gastrectomy

Background The clinical features and therapeutic strategies for gastric cancer with positive peritoneal washing cytology but without visible gross peritoneal metastasis have not been defined. The aim of this study was to evaluate the effect and clinical prognostic value of postoperative chemotherapy in gastric cancer patients with positive peritoneal washing cytology without gross peritoneal metastasis who underwent radical D2 gastrectomy in terms of disease-free survival (DFS) and overall survival (OS). Materials and Methods Intraoperative peritoneal washing cytology was performed in 285 patients who underwent radical D2 gastrectomy between April 2004 and May 2016. Of them, 88 patients with positive cytology but without gross peritoneal metastasis were included in the study. In total, 64 patients received postoperative chemotherapy, whereas 24 patients underwent surgery only. Results Most gastric cancer patients with positive cytology without gross peritoneal metastasis demonstrated pT4 and/or pN3 disease. Postoperative chemotherapy improved DFS and OS compared to surgery only in gastric cancer patients with positive cytology without gross peritoneal metastasis (median DFS 11.63 vs. 6.98 months, p < 0.001; median OS 25.50 vs. 12.11 months, p < 0.001). In multivariate analyses of gastric cancer patients with positive cytology without gross peritoneal metastasis, no chemotherapy was the strongest clinical factor for poorer DFS (hazard ratio [HR] 3.76, p < 0.001) or OS (HR 4.37, p < 0.001). Conclusion Postoperative chemotherapy improves the survival outcome compared to surgery alone in gastric cancer patients with positive peritoneal washing cytology but without visible gross peritoneal metastasis who underwent radical D2 gastrectomy.

Curcumin inhibits liver metastasis of gastric cancer through reducing circulating tumor cells

Primary gastric cancer (PGC) is the fourth most common malignant human cancer and the second leading cause of death worldwide. The majority of the subjects of PGC is diagnosed at a late stage, resulting in poor prognosis and therapeutic outcome, largely attributable to dissemination of tumor cells into circulation as circulating tumor cells (CTCs) and their formation of distal tumor. Curcumin is an active ingredient from the rhizome of the plant Curcuma longa. Here, we assessed whether treatment with Curcumin may reduce the incidence of metastatic tumor formation in liver in mice carrying PGC. We found that Curcumin treatment significantly reduced the presence of CTCs and formation of liver tumor. Mechanistically, Curcumin reduced CXCR4 expression in PGCs in vitro and in vivo, and thus likely inhibited metastasis of PGC through suppression of stromal cell -derived factor-1/CXCR4 signaling. Thus, our study suggests that Curcumin may inhibit liver metastasis of PGC through reducing CTCs.

Treatment of PERItoneal disease in Stomach Cancer with cytOreductive surgery and hyperthermic intraPEritoneal chemotherapy: PERISCOPE I initial results

BACKGROUND

The role of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) in gastric cancer is unknown. This non-randomized dose-finding phase I-II study was designed to assess the safety and feasibility of HIPEC, following systemic chemotherapy, in patients with gastric cancer and limited peritoneal dissemination. The maximum tolerated dose of normothermic intraperitoneal docetaxel in combination with a fixed dose of intraperitoneal oxaliplatin was also explored.

METHODS

Patients with resectable cT3-cT4a gastric adenocarcinoma with limited peritoneal metastases and/or tumour-positive peritoneal cytology were included. An open HIPEC technique was used with 460 mg/m² hyperthermic oxaliplatin for 30 min followed by normothermic docetaxel for 90 min in escalating doses (0, 50, 75 mg/m² ).

RESULTS

Between 2014 and 2017, 37 patients were included. Of 25 patients who completed the full study protocol, four were treated at dose level 1 (0 mg/m² docetaxel), six at dose level 2 (50 mg/m² ) and four at dose level 3 (75 mg/m² ). At dose level 3, two dose-limiting toxicities occurred, both associated with postoperative ileus. Thereafter, another 11 patients were treated at dose level 2, with no more dose-limiting toxicities. Based on this, the maximum tolerated dose was 50 mg/m² intraperitoneal docetaxel. Serious adverse events were scored in 17 of 25 patients. The reoperation rate was 16 per cent (4 of 25) and the treatment-related mortality rate was 8 per cent (2 patients, both in dose level 3).

CONCLUSION

Gastrectomy combined with cytoreductive surgery and HIPEC was feasible using 460 mg/m² oxaliplatin and 50 mg/m² normothermic docetaxel.

Recent Advances in Intra-peritoneal Chemotherapy for Gastric Cancer

Peritoneal metastasis (PM) frequently occurs in patients with gastric cancer (GC) and confers a dismal prognosis despite advances in systemic chemotherapy. While systemic chemotherapy has poor peritoneal penetration, intraperitoneal (IP) chemotherapy remains sequestered, resulting in high peritoneal drug concentrations with less systemic side-effects. The first application of IP treatment was hyperthermic intraperitoneal chemotherapy (HIPEC) with cytoreductive surgery (CRS) for gastric cancer peritoneal metastasis (GCPM); but was associated with an increased morbidity and mortality rate without significantly improving overall survival (OS). While CRS confers limited benefit, the potential role of prophylactic HIPEC and laparoscopic neoadjuvant HIPEC are currently being evaluated. Combination systemic and IP chemotherapy (SIPC) gained popularity in the 1990s, since it provided the benefits of IP treatment while reducing surgical morbidity, demonstrating promising early results in multiple Phase II trials. Unfortunately, these findings were not confirmed in the recent PHOENIX-GC randomized controlled trial; therefore, the appropriate treatment for GCPM remains controversial. Small observational studies from Japan and Singapore have reported successful downstaging of PM in GC patients receiving SIPC who subsequently underwent conversion gastrectomy with a median OS of 21.6–34.6 months. Recently, the most significant development in IP-directed therapy is pressurized IP aerosol chemotherapy (PIPAC). Given that aerosol chemotherapy achieves a wider distribution and deeper penetration, the outcomes of multiple ongoing trials assessing its efficacy are eagerly awaited. Indeed, IP-directed therapy has evolved rapidly in the last 3 decades, with an encouraging trend toward improved outcomes in GCPM, and may offer some hope for an otherwise fatal disease.

Efficacy of a Third-Generation Oncolytic Herpes Virus G47Δ in Advanced Stage Models of Human Gastric Cancer

Advanced gastric cancer, especially scirrhous gastric cancer with peritoneal dissemination, remains refractory to conventional therapies. G47Δ, a third-generation oncolytic herpes simplex virus type 1, is an attractive novel therapeutic agent for solid cancer. In this study, we investigated the therapeutic potential of G47Δ for human gastric cancer. In vitro, G47Δ showed good cytopathic effects and replication capabilities in nine human gastric cancer cell lines tested. In vivo, intratumoral inoculations with G47Δ (2 × 10⁵ or 1 × 10⁶ plaque-forming units [PFU]) significantly inhibited the growth of subcutaneous tumors (MKN45, MKN74, and 44As3). To evaluate the efficacy of G47Δ for advanced-stage models of gastric cancer, we generated an orthotopic tumor model and peritoneal dissemination models of human scirrhous gastric cancer (MKN45-luc and 44As3Luc), which have features mimicking intractable scirrhous cancer patients. G47Δ (1 × 10⁶ PFU) was constantly efficacious whether administered intratumorally or intraperitoneally in the clinically relevant models. Notably, G47Δ injected intraperitoneally readily distributed to, and selectively replicated in, disseminated tumors. Furthermore, flow cytometric analyses of tumor-infiltrating cells in subcutaneous tumors revealed that intratumoral G47Δ injections markedly decreased M2 macrophages while increasing M1 macrophages and natural killer (NK) cells. These findings indicate the usefulness of G47Δ for treating human gastric cancer, including scirrhous gastric cancer and the ones in advanced stages.