Peritoneal carcinomatosis of colorectal origin: Incidence, prognosis and treatment options

Abdominal compartment syndrome during intraoperative hyperthermic intraperitoneal chemotherapy following debulking surgery for colorectal cancer: A case report

INTRODUCTION

Colorectal cancer leads to peritoneal metastasis in 8-15 % of cases and necessitates treatments, such as hyperthermic intraperitoneal chemotherapy (HIPEC). However, HIPEC may result in perioperative complications, some often overlooked, such as abdominal compartment syndrome.

CASE PRESENTATION

A 52-year-old female with colorectal cancer and peritoneal metastasis underwent debulking surgery followed by HIPEC. During HIPEC, a sudden increase in airway pressure and severe hypotension were noted. Pneumothorax with abdominal compartment syndrome (ACS) was suspected and HIPEC was terminated. Despite intravenous fluids and vasopressors, she experienced circulatory and respiratory collapse. Laparotomy sutures were promptly removed, which effectively alleviated the intra-abdominal hypertension and immediately restored the vital signs. An inadequately repaired diaphragm defect was identified and repaired. A chest tube was inserted for pleural effusion.

DISCUSSION

ACS is characterized by an increase in abdominal cavity pressure above 20 mmHg, leading to end-organ damage. It can mimic physiological effects of HIPEC and result in adverse outcomes. Early detection of ACS is essential, especially when complicated by pneumothorax from diaphragmatic tumor dissection. The closed technique for HIPEC, while efficient, can increase the risk of ACS and requires careful management.

CONCLUSIONS

This case underscores the complexity of HIPEC and the importance of promptly identifying and managing ACS during the procedure. Monitoring intra-abdominal pressure during HIPEC is essential. Thoroughly check for iatrogenic injuries, including the diaphragm, is crucial before starting before HIPEC.

Material density dual-energy CT images: value added in early diagnosis of peritoneal carcinomatosis : Original research

OBJECTIVE

To assess the value of material density (MD) images generated from a rapid kilovoltage-switching dual-energy CT (rsDECT) in early detection of peritoneal carcinomatosis (PC).

MATERIALS AND METHODS

Thirty patients (60 ± 13 years; 24 women) with PC detected on multiple abdominal DECT scans were included. Four separate DECTs with varying findings of PC from each patient were used for qualitative/quantitative analysis, resulting in a total of 120 DECT scans (n = 30 × 4). Three radiologists independently reviewed DECT images (65 keV alone and 65 keV + MD) for diagnosis of PC (diagnostic confidence, lesion conspicuity, sharpness/delineation and image quality) using a 5-point Likert scale. Quantitative estimation of contrast-to-noise ratio (CNR) was done. Wilcoxon signed-rank test and Odds ratio calculation were used to compare between the two protocols. Inter-observer agreement was evaluated using Kappa coefficient analysis. P values < 0.05 were considered statistically significant.

RESULTS

65 keV + MD images showed a slightly higher sensitivity (89%[95%CI:84,92]) for PC detection compared with 65 keV images alone without statistical significance (84%[95%CI:78,88], p = 0.11) with the experienced reader showing significant improvement (98%[95%CI:93,100] vs. 90%[95%CI:83,94], p = 0.02). On a per-patient basis, use of MD images allowed earlier diagnosis for PC in an additional 13-23% of patients. On sub-group analysis, earlier diagnosis of PC was particularly beneficial in patients with BMI ≤ 29.9 kg/m2. 65 keV + MD images showed higher diagnostic confidence, lesion conspicuity, and lesion sharpness for the experienced reader (p < 0.001). CNR was higher in MD images (1.7 ± 0.5) than 65 keV images (0.1 ± 0.02, p < 0.001). All readers showed moderate interobserver agreement for determining PC by both protocols (κ = 0.58 and κ = 0.47).

CONCLUSION

MD images allow earlier and improved detection of PC with the degree of benefit varying based on reader experience and patient body habitus.

A pan-cancer dye for solid-tumour screening, resection and wound monitoring via short-wave and near-infrared fluorescence imaging

The efficacy of fluorescence-guided surgery in facilitating the real-time delineation of tumours depends on the optical contrast of tumour tissue over healthy tissue. Here we show that CJ215-a commercially available, renally cleared carbocyanine dye sensitive to apoptosis, and with an absorption and emission spectra suitable for near-infrared fluorescence imaging (wavelengths of 650-900 nm) and shortwave infrared (SWIR) fluorescence imaging (900-1,700 nm)-can facilitate fluorescence-guided tumour screening, tumour resection and the assessment of wound healing. In tumour models of either murine or human-derived breast, prostate and colon cancers and of fibrosarcoma, and in a model of intraperitoneal carcinomatosis, imaging of CJ215 with ambient light allowed for the delineation of nearly all tumours within 24 h after intravenous injection of the dye, which was minimally taken up by healthy organs. At later timepoints, CJ215 provided tumour-to-muscle contrast ratios up to 100 and tumour-to-liver contrast ratios up to 18. SWIR fluorescence imaging with the dye also allowed for quantifiable non-contact wound monitoring through commercial bandages. CJ215 may be compatible with existing and emerging clinical solutions.

Non-Coding RNAs in Peritoneal Carcinomatosis: From Bench to Bedside

Peritoneal carcinomatosis represents an advanced stage of tumors within the peritoneal cavity. Once considered an incurable terminal cancer metastasis, contemporary medicine is on the hunt for certain potentially curative options alongside the present day's palliative disease management. However, for most patients, peritoneal carcinomatosis continues to pose a fatal late-stage prognosis with a grim future outlook. Over the past two decades, non-coding RNAs have garnered significant attention due to their undeniable significance in regulating cellular processes across all levels. Disruption of the intricate regulation led by non-coding RNAs has been demonstrated to have a substantial impact on various human diseases, particularly in cancer, including solid tumors originating from the organs of the peritoneal cavity. This review aims to offer a comprehensive overview of the current state of knowledge in the under-researched field of peritoneal carcinomatosis, focusing specifically on the role of non-coding RNAs in the development of this condition and delineating potential avenues for future research.

Developments in the Use of Indocyanine Green (ICG) Fluorescence in Colorectal Surgery

Indocyanine Green (ICG) has significantly advanced minimally invasive surgery. It is widely recognized for its ability to visualize blood vessel patency in real-time across various surgical specialties. While its primary use in colorectal surgery is to evaluate anastomoses for leaks, numerous other applications have been documented in the literature. In this review, we aim to explore both established and emerging applications of ICG fluorescence in colorectal surgery, with the goal of improving patient outcomes. This includes preoperative tumor marking and the detection of metastatic disease. Some applications, such as lymphatic mapping, require further research to determine their impact on clinical practices. Conversely, others, like the intraoperative localizations of ureters, necessitate additional procedures and are not yet widely accepted by the surgical community. However, the development of alternative compounds could offer better solutions. Future research should focus on areas like quantitative ICG and protocol standardization in prospective multicenter studies.

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.

Long-Term Outcomes following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Carcinomatosis of Colorectal Origin

BACKGROUND

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a major treatment of colorectal peritoneal carcinomatosis (CPC). The aim was to determine the disease-free survival (DFS) and overall survival (OS) of patients undergoing CRS-HIPEC for CPC and factors associated with long-term survival (LTS).

METHODS

consecutive CPC patients who underwent CRS-HIPEC at a HIPEC center between 2007 and 2021 were included. Actual survival was calculated, and Cox proportional hazards models were used to identify factors associated with OS, DFS and LTS.

RESULTS

there were 125 patients with CPC who underwent primary CRS-HIPEC, with mean age of 54.5 years. Median follow-up was 31 months. Average intraoperative PCI was 11, and complete cytoreduction (CC-0) was achieved in 96.8%. Median OS was 41.6 months (6-196). The 2-year and 5-year OS were 68% and 24.8%, respectively, and the 2-year DFS was 28.8%. Factors associated with worse OS included pre-HIPEC systemic therapy, synchronous extraperitoneal metastasis, and PCI ≥ 20 (p < 0.05). Progression prior to CRS-HIPEC was associated with worse DFS (p < 0.05). Lower PCI, fewer complications, lower recurrence and longer DFS were associated with LTS (p < 0.05).

CONCLUSION

CRS and HIPEC improve OS in CPC patients but they have high disease recurrence. Outcomes depend on preoperative therapy response, extraperitoneal metastasis, and peritoneal disease burden.

Application of artificial intelligence in the diagnosis, treatment, and recurrence prediction of peritoneal carcinomatosis

Peritoneal carcinomatosis (PC) is a type of secondary cancer which is not sensitive to conventional intravenous chemotherapy. Treatment strategies for PC are usually palliative rather than curative. Recently, artificial intelligence (AI) has been widely used in the medical field, making the early diagnosis, individualized treatment, and accurate prognostic evaluation of various cancers, including mediastinal malignancies, colorectal cancer, lung cancer more feasible. As a branch of computer science, AI specializes in image recognition, speech recognition, automatic large-scale data extraction and output. AI technologies have also made breakthrough progress in the field of peritoneal carcinomatosis (PC) based on its powerful learning capacity and efficient computational power. AI has been successfully applied in various approaches in PC diagnosis, including imaging, blood tests, proteomics, and pathological diagnosis. Due to the automatic extraction function of the convolutional neural network and the learning model based on machine learning algorithms, AI-assisted diagnosis types are associated with a higher accuracy rate compared to conventional diagnosis methods. In addition, AI is also used in the treatment of peritoneal cancer, including surgical resection, intraperitoneal chemotherapy, systemic chemotherapy, which significantly improves the survival of patients with PC. In particular, the recurrence prediction and emotion evaluation of PC patients are also combined with AI technology, further improving the quality of life of patients. Here we have comprehensively reviewed and summarized the latest developments in the application of AI in PC, helping oncologists to comprehensively diagnose PC and provide more precise treatment strategies for patients with PC.

Peritoneal carcinomatosis in mouse models

Peritoneal carcinomatosis (PCa) represents a metastatic stage of a disease with unmet therapeutic options. Malignant cells from primary tumors (gastrointestinal or gynecologic malignancies) invade the peritoneal cavity and eventually seed onto peritoneal surfaces, with the omentum being the most common nest area. With a median survival of less than 6 months, PCa has a dismal prognosis that can be improved with treatments only available to a select few individuals with low tumor burden. Thus, the discovery of novel and effective therapies for this disease depends on reliable animal models. Here, we describe a method to generate syngeneic PCa mouse models based on intraperitoneal (i.p.) administration of tumor cells. This model allows to follow-up cancer progression in PCa models from ovarian and colorectal origins monitoring mice bodyweight changes, ascites development and overall survival. Moreover, luciferase-expressing tumor cells can also be used to assess tumor growth after i.p. injection through in vivo bioluminescence quantification. The establishment of reliable, easy-to-monitor and reproducible intraperitoneal syngeneic tumors models, as described here, is the first step to develop cutting-edge therapies against PCa.

Epidemiology of Stage IV Colorectal Cancer: Trends in the Incidence, Prevalence, Age Distribution, and Impact on Life Span

Colorectal cancer is a common malignancy in men and women. Historically, stage IV colorectal cancer has 10 to 15% five-year survival. Developments in the management of colorectal metastatic disease have helped improve the overall survival of stage IV colorectal cancers from 12 to 30 months with some patients achieving disease-free survival.

A pan-cancer agent for screening, resection and wound monitoring via NIR and SWIR imaging

Fluorescence guided surgery (FGS) facilitates real time tumor delineation and is being rapidly established clinically. FGS efficacy is tied to the utilized dye and provided tumor contrast over healthy tissue. Apoptosis, a cancer hallmark, is a desirable target for tumor delineation. Here, we preclinically in vitro and in vivo, validate an apoptosis sensitive commercial carbocyanine dye (CJ215), with absorption and emission spectra suitable for near infrared (NIR, 650-900nm) and shortwave infrared (SWIR, 900-1700nm) fluorescence imaging (NIRFI, SWIRFI). High contrast SWIRFI for solid tumor delineation is demonstrated in multiple murine and human models including breast, prostate, colon, fibrosarcoma and intraperitoneal colorectal metastasis. Organ necropsy and imaging highlighted renal clearance of CJ215. SWIRFI and CJ215 delineated all tumors under ambient lighting with a tumor-to-muscle ratio up to 100 and tumor-to-liver ratio up to 18, from 24 to 168 h post intravenous injection with minimal uptake in healthy organs. Additionally, SWIRFI and CJ215 achieved non-contact quantifiable wound monitoring through commercial bandages. CJ215 provides tumor screening, guided resection, and wound healing assessment compatible with existing and emerging clinical solutions.

Single-cell deconvolution reveals high lineage- and location-dependent heterogeneity in mesenchymal multivisceral stage 4 colorectal cancer

Metastasized colorectal cancer (CRC) is associated with a poor prognosis and rapid disease progression. Besides hepatic metastasis, peritoneal carcinomatosis is the major cause of death in Union for International Cancer Control (UICC) stage IV CRC patients. Insights into differential site-specific reconstitution of tumor cells and the corresponding tumor microenvironment are still missing. Here, we analyzed the transcriptome of single cells derived from murine multivisceral CRC and delineated the intermetastatic cellular heterogeneity regarding tumor epithelium, stroma, and immune cells. Interestingly, we found an intercellular site-specific network of cancer-associated fibroblasts and tumor epithelium during peritoneal metastasis as well as an autologous feed-forward loop in cancer stem cells. We furthermore deciphered a metastatic dysfunctional adaptive immunity by a loss of B cell-dependent antigen presentation and consecutive effector T cell exhaustion. Furthermore, we demonstrated major similarities of this murine metastatic CRC model with human disease and - based on the results of our analysis - provided an auspicious site-specific immunomodulatory treatment approach for stage IV CRC by intraperitoneal checkpoint inhibition.

Enhanced Chemo-Immunotherapy Strategy Utilizing Injectable Thermosensitive Hydrogel for The Treatment of Diffuse Peritoneal Metastasis in Advanced Colorectal Cancer

Patients with colorectal cancer (CRC) and diffuse peritoneal metastasis (PM) are not eligible for surgical intervention. Thus, palliative treatment remains the standard of care in clinical practice. Systemic chemotherapy fails to cause drug accumulation at the lesion sites, while intraperitoneal chemotherapy (IPC) is limited by high clearance rates and associated complications. Given the poor prognosis, a customized OxP/R848@PLEL hydrogel delivery system has been devised to improve the clinical benefit of advanced CRC with diffuse PM. This system is distinguished by its simplicity, security, and efficiency. Specifically, the PLEL hydrogel exhibits excellent injectability and thermosensitivity, enabling the formation of drug depots within the abdominal cavity, rendering it an optimal carrier for IPC. Oxaliplatin (OxP), a first-line drug for advanced CRC, is cytotoxic and enhances the immunogenicity of tumors by inducing immunogenic cell death. Furthermore, OxP and resiquimod (R848) synergistically enhance the maturation of dendritic cells, promote the expansion of cytotoxic T lymphocytes, and induce the formation of central memory T cells. Moreover, R848 domesticates macrophages to an anti-tumor phenotype. OxP/R848@PLEL effectively eradicates peritoneal metastases, completely inhibits ascites production, and significantly prolongs mice lifespan. As such, it provides a promising approach to managing diffuse PM in patients with CRC without surgical indications.

Effect of Intraperitoneal Chemotherapy with Regorafenib on IL-6 and TNF-α Levels and Peritoneal Cytology: Experimental Study in Rats with Colorectal Peritoneal Carcinomatosis

Cytoreductive surgery (CRS), combined with hyperthermic intraperitoneal chemotherapy, has significantly improved survival outcomes in patients with peritoneal carcinomatosis from colorectal cancer (CRC). Regorafenib is an oral agent administered in patients with refractory metastatic CRC. Our aim was to investigate the outcomes of intraperitoneal administration of regorafenib for intraperitoneal chemotherapy (IPEC) or/and CRS in a rat model of colorectal peritoneal metastases regarding immunology and peritoneal cytology. A total of 24 rats were included. Twenty-eight days after carcinogenesis induction, rats were randomized into following groups: group A: control group; group B: CRS only; group C: IPEC only; and group D: CRS + IPEC. On day 56 after carcinogenesis, euthanasia and laparotomy were performed. Serum levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) as well as peritoneal cytology were investigated. Groups B and D had statistically significant lower mean levels of IL-6 and TNF-α compared to groups A and C, but there was no significant difference between them. Both B and D groups presented a statistically significant difference regarding the rate of negative peritoneal cytology, when compared to the control group, but not to group C. In conclusion, regorafenib-based IPEC, combined with CRS, may constitute a promising tool against peritoneal carcinomatosis by altering the tumor microenvironment.

Predictive Genetic Biomarkers for the Development of Peritoneal Metastases in Colorectal Cancer

Metastatic colorectal cancer (CRC) is a common cause of cancer-related mortality, of which peritoneal metastases (PMs) have the worse outcome. Metastasis-specific markers may help predict the spread of tumor cells and select patients for preventive strategies. This exploratory pilot study aimed to gain more insight into genetic alterations in primary CRC tumors, which might be a predictive factor for the development of PM. Forty patients with T3 stage CRC were retrospectively divided in three groups: without metachronous metastases during 5-year follow-up (M0, n = 20), with metachronous liver metastases (LM, n = 10) and with metachronous PM (PM, n = 10). Patients with synchronous metastases were excluded. Primary formalin-fixed paraffin-embedded tumor samples were analyzed via comprehensive genome sequencing (TSO500 analysis) to identify DNA alterations and RNA fusion transcripts in 523 genes and 55 genes, respectively. Thirty-eight samples were included for final analysis. Four M0 tumors and one PM tumor were microsatellite instable. BRAF mutations were uniquely identified in three microsatellite-stable (MSS) PM tumors (37.5%, p = 0.010). RNA analysis showed an additional FAM198A-RAF1 fusion in one PM sample. BRAF p.V600E mutations were only present in PM patients with MSS tumors. Greater attention should be paid to BRAF-mutated tumors in relation to the development of metachronous PM.

Comparison of genetic variation between primary colorectal cancer and metastatic peritoneal cancer

BACKGROUND

Among cancer metastases by primary colorectal cancer (CRC), peritoneal metastasis is the second most common metastatic lesion after liver metastasis. In treating metastatic CRC, it is very important to differentiate targeted-therapy and chemotherapy according to the characteristics of each lesion because the genetic variation of the primary and metastatic lesions are different. However, there are few studies of genetic characteristics on peritoneal metastasis caused by primary CRC, so molecular-level studies are continuously required.

OBJECTIVE

We propose an appropriate peritoneal metastasis treatment policy by identifying the genetic characteristics between primary CRC and synchronous peritoneal metastatic lesions.

METHODS

Primary CRC and synchronous peritoneal metastasis samples were analyzed in pairs from six patients using Comprehensive Cancer Panel (409 cancer-related genes, Thermo Fisher Scientific, USA) and next-generation sequencing (NGS).

RESULTS

The mutations were commonly found on the KMT2C and THBS1 genes in both primary CRC and peritoneal metastasis. The PDE4DIP gene was mutated in all cases except for on a sample of peritoneal metastasis. As a result of analysis using the mutation database, we confirmed that the gene mutations of primary CRC and the peritoneal metastasis derived from it showed the same tendency, although we did not accompany the gene expression level or epigenetic study.

CONCLUSION

It is thought that the treatment policy through molecular genetic testing of primary CRC can also be applied to peritoneal metastasis treatment. Our study is expected to be the basis for further peritoneal metastasis research.

DNA and RNA Alterations Associated with Colorectal Peritoneal Metastases: A Systematic Review

BACKGROUND

As colorectal cancer (CRC) patients with peritoneal metastases (PM) have a poor prognosis, new treatment options are currently being investigated for CRC patients. Specific biomarkers in the primary tumor could serve as a prediction tool to estimate the risk of distant metastatic spread. This would help identify patients eligible for early treatment.

AIM

To give an overview of previously studied DNA and RNA alterations in the primary tumor correlated to colorectal PM and investigate which gene mutations should be further studied.

METHODS

A systematic review of all published studies reporting genomic analyses on the primary tissue of CRC tumors in relation to PM was undertaken according to PRISMA guidelines.

RESULTS

Overall, 32 studies with 18,906 patients were included. BRAF mutations were analyzed in 17 articles, of which 10 found a significant association with PM. For all other reported genes, no association with PM was found. Two analyses with broader cancer panels did not reveal any new biomarkers.

CONCLUSION

An association of specific biomarkers in the primary tumors of CRC patients with metastatic spread into peritoneum could not be proven. The role of BRAF mutations should be further investigated. In addition, studies searching for potential novel biomarkers are still required.

Hyperthermic Intraperitoneal Chemotherapy Following Cytoreductive Surgery for Colorectal Peritoneal Carcinomatosis Patients: A Review

Colorectal peritoneal carcinomatosis (CPC) is an advanced malignancy and is typically associated with a poor prognosis. Hyperthermic intraperitoneal chemotherapy (HIPEC) following complete cytoreductive surgery (CRS) is a novel, advanced loco-regional treatment for colorectal cancer that is currently being used to treat peritoneal carcinomatosis (PC). The present review aims to describe the evidence-based literature on the efficacy and safety of this treatment approach in patients with PC originating from colorectal cancer and to summarize its complications. All published literature regarding the efficacy of HIPEC for the treatment of CPC was reviewed; 16 studies were included in this paper. The overall survival rate for the HIPEC group ranged from 63% to 93%. The overall median survival for the HIPEC and non-HIPEC groups ranged from 13 to 60.1 months and 12.6 to 41.2 months, respectively. The overall median survival of patients in the HIPEC group was comparatively better than those in the non-HIPEC group. There was insufficient evidence to suggest whether this treatment regimen was associated with a high or low morbidity rate in comparison to other groups. However, the mortality rate associated with this treatment regimen was low. In conclusion, the present data provide insufficient evidence regarding the beneficial effects of using HIPEC following CRS treatment. Therefore, further studies are required to determine the benefits of HIPEC for CPC patients.

Nomogram for prediction of peritoneal metastasis risk in colorectal cancer

OBJECTIVE

Peritoneal metastasis is difficult to diagnose using traditional imaging techniques. The main aim of the current study was to develop and validate a nomogram for effectively predicting the risk of peritoneal metastasis in colorectal cancer (PMCC).

METHODS

A retrospective case-control study was conducted using clinical data from 1284 patients with colorectal cancer who underwent surgery at the First Affiliated Hospital of Guangxi Medical University from January 2010 to December 2015. Least absolute shrinkage and selection operator (LASSO) regression was applied to optimize feature selection of the PMCC risk prediction model and multivariate logistic regression analysis conducted to determine independent risk factors. Using the combined features selected in the LASSO regression model, we constructed a nomogram model and evaluated its predictive value via receiver operating characteristic (ROC) curve analysis. The bootstrap method was employed for repeated sampling for internal verification and the discrimination ability of the prediction models evaluated based on the C-index. The consistency between the predicted and actual results was assessed with the aid of calibration curves.

RESULTS

Overall, 96 cases of PMCC were confirmed via postoperative pathological diagnosis. Logistic regression analysis showed that age, tumor location, perimeter ratio, tumor size, pathological type, tumor invasion depth, CEA level, and gross tumor type were independent risk factors for PMCC. A nomogram composed of these eight factors was subsequently constructed. The calibration curve revealed good consistency between the predicted and actual probability, with a C-index of 0.882. The area under the curve (AUC) of the nomogram prediction model was 0.882 and its 95% confidence interval (CI) was 0.845-0.919. Internal validation yielded a C-index of 0.868.

CONCLUSION

We have successfully constructed a highly sensitive nomogram that should facilitate early diagnosis of PMCC, providing a robust platform for further optimization of clinical management strategies.

Metachronous peritoneal metastases in patients with pT4b colon cancer: An international multicenter analysis of intraperitoneal versus retroperitoneal tumor invasion

BACKGROUND

It was hypothesized that colon cancer with only retroperitoneal invasion is associated with a low risk of peritoneal dissemination. This study aimed to compare the risk of metachronous peritoneal metastases (mPM) between intraperitoneal and retroperitoneal invasion.

METHODS

In this international, multicenter cohort study, patients with pT4bN0-2M0 colon cancer who underwent curative surgery were categorized as having intraperitoneal invasion (e.g. bladder, small bowel, stomach, omentum, liver, abdominal wall) or retroperitoneal invasion only (e.g. ureter, pancreas, psoas muscle, Gerota's fascia). Primary outcome was 5-year mPM cumulative rate, assessed by Kaplan-Meier analysis.

RESULTS

Out of 907 patients with pT4N0-2M0 colon cancer, 198 had a documented pT4b category, comprising 170 patients with intraperitoneal invasion only, 12 with combined intra- and retroperitoneal invasion, and 16 patients with retroperitoneal invasion only. At baseline, only R1 resection rate significantly differed: 4/16 for retroperitoneal invasion only versus 8/172 for intra- +/- retroperitoneal invasion (p = 0.010). Overall, 22 patients developed mPM during a median follow-up of 45 months. Two patients with only retroperitoneal invasion developed mPM, both following R1 resection. The overall 5-year mPM cumulative rate was 13% for any intraperitoneal invasion and 14% for retroperitoneal invasion only (Log Rank, p = 0.878), which was 13% and 0%, respectively, in patients who had an R0 resection (Log Rank, p = 0.235).

CONCLUSION

This study suggests that pT4b colon cancer patients with only retroperitoneal invasion who undergo an R0 resection have a negligible risk of mPM, but this is difficult to prove because of its rarity. This observation might have implications regarding individualized follow-up.

Perception, knowledge and protective practices for surgical staff handling antineoplastic drugs during HIPEC and PIPAC

Objectives

Two surgical techniques used for peritoneal metastasis involve a risk of exposure to antineoplastic drugs (ADs): hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC). The objective of this study was to assess the differences in perception, training, and knowledge of the risks as well as in the protection practices and occupational exposures of all worker categories.

Methods

This descriptive study, led in two hospitals from two distant French regions, was performed through a face-to-face interview and assessed the perception, knowledge and handling practices of ADs by a questionnaire consisting of 52 questions.

Results

Fifty-one professionals participated in this survey. A total of 29.4% (n=15) professionals were afraid to handle ADs. Very few workers have been trained on handling ADs during initial training dedicated to all caregiver (5.9%; n=3). HIPEC is considered to involve a higher risk of exposure to ADs than PIPAC (81.6% (n=31) vs. 57.9% (n=22), respectively, p=0.022, agreement 65.8%). Protective equipment is considered to be less suitable for HIPEC than for PIPAC (29% (n=11) vs. 10.5% (n=4), respectively, p=0.016, agreement 81.6%). Concerning the potential AD contamination location, the participants identified a significant difference between these two practices. During HIPEC, 15.7% (n=6) of caregivers indicated that they had negative symptoms perceived in their practice vs. 2.6% (n=1) during PIPAC.

Conclusions

This study shows that perception, knowledge and protection practices are different between HIPEC and PIPAC. It also shows a difference between the worker categories. In view of the difficulties in making operating room staff available, the related training programmes must have an adapted format.

Cancer follow-up supported by patient-reported outcomes in patients undergoing intended curative complex surgery for advanced cancer

BACKGROUND AND AIM

Patient activation (PA) and Patient Involvement (PI) are considered elements in good survivorship. We aimed to evaluate the effect of a follow-up supported by electronic patient-reported outcomes (ePRO) on PA and PI.

METHOD

From February 2017 to January 2019, we conducted an explorative interventional study. We included 187 patients followed after intended curative complex surgery for advanced cancer at two different Departments at a University Hospital. Prior to each follow-up consultation, patients used the ePRO to screen themselves for clinical important symptoms, function and needs. The ePRO was graphically presented to the clinician during the follow-up, aiming to facilitate patient activation and involvement in each follow-up. PA was measured by the Patient Activation Measurement (PAM), while PI was measured by five indicator questions. PAM and PI data compared between (- ePRO) and interventional (+ ePRO) consultations. PAM data were analysed using a linear mixed effect regression model with intervention (yes/no) and time along with the interaction between them as categorical fixed effects. The analyses were further adjusted for time (days) since surgery.

RESULTS

According to our data, ePRO supported consultations did not improve PA. The average mean difference in PAM score between + ePRO and - ePRO consultations were - 0.2 (95% confidence interval - 2.6; 2.2, p = 0.9). There was no statistically significant improvement in PAM scores over time in neither + ePRO nor - ePRO group (p = 0.5). Based on the five PI-indicator questions, the majority of all consultations were evaluated as "some, much or very much" involved in consultation; providing a wider scope of dialogue, encouraged patients to ask questions and share their experiences and concerns. Nevertheless, another few patients reported not to be involved at all in the consultations.

CONCLUSION

We did not demonstrate evidence for ePRO supported consultations to improve patient activation, and patient activation did not improve over time. Our results generate the hypotheses that factors related to ePRO supported consultation had the potential to support PI by offering a wider scope of dialogue, and encourage patients to ask questions and share their experiences and concerns during follow-up.

Oncolytic vaccinia virus reinvigorates peritoneal immunity and cooperates with immune checkpoint inhibitor to suppress peritoneal carcinomatosis in colon cancer

Background

Peritoneal carcinomatosis (PC) is a common and devastating manifestation of colon cancer and refractory to conventional anticancer therapeutics. During the peritoneal dissemination of colon cancer, peritoneal immunity is nullified by various mechanisms of immune evasion. Here, we employed the armed oncolytic vaccinia virus mJX-594 (JX) to rejuvenate the peritoneal antitumor immune responses in the treatment of PC.

Methods

PC model of MC38 colon cancer was generated and intraperitoneally treated with JX and/or anti-programmed cell death protein 1 (PD-1) antibody. The peritoneal tumor burden, vascular leakage, and malignant ascites formation were then assessed. Tumors and peritoneal lavage cells were analyzed by flow cytometry, multiplex tissue imaging, and a NanoString assay.

Results

JX treatment effectively suppressed peritoneal cancer progression and malignant ascites formation. It also restored the peritoneal anticancer immunity by activating peritoneal dendritic cells (DCs) and CD8⁺ T cells. Moreover, JX selectively infected and killed peritoneal colon cancer cells and promoted the intratumoral infiltration of DCs and CD8⁺ T cells into peritoneal tumor nodules. JX reinvigorates anticancer immunity by reprogramming immune-related transcriptional signatures within the tumor microenvironment. Notably, JX cooperates with immune checkpoint inhibitors (ICIs), anti-programmed death-1, anti-programmed death-ligand 1, and anti-lymphocyte-activation gene-3 to elicit a stronger anticancer immunity that eliminates peritoneal metastases and malignant ascites of colon cancer compared with JX or ICI alone.

Conclusions

Intraperitoneal immunotherapy with JX restores peritoneal anticancer immunity and potentiates immune checkpoint blockade to suppress PC and malignant ascites in colon cancer.

Starting a peritoneal carcinomatosis treatment program in a developing country: A prospective analysis

BACKGROUND

Cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) has become a valuable treatment strategy for selected patients with peritoneal carcinomatosis (PC). In Chile, it is an emerging technique. The aim of this study is to describe our protocol and report our perioperative results.

METHODS

A prospectively maintained database for patients undergoing exploratory surgery for PC was reviewed. Eligible patients were selected using the peritoneal cancer index in correlation with the primary tumor. Patients underwent HIPEC using mitomycin C. Clinical data and postoperative results were analyzed.

RESULTS

Seventy-six patients underwent exploratory surgery. Most patients were female (55%) with a median age of 62 years (range, 25-83). Complete CRS and HIPEC were achieved in 53 patients. The most frequent primary tumor site was colon-rectum (49%). The median number of resected organs was 4 (range, 1-13). Overall 90-day incidence of major complications was 26%. After a median follow-up of 26 months, 44 patients (83%) in the resected group were alive with no evidence of disease.

CONCLUSIONS

The PC treatment program at our institution has been established in a safe manner, with acceptable morbidity comparable to high-volume centers. A comprehensive preoperative evaluation, careful patient selection, and a cohesive team are necessary for successful results.

Synchronous peritoneal metastases from lung cancer: incidence, associated factors, treatment and survival: a Dutch population-based study

Peritoneal metastases (PM) from lung cancer are rare and it is unknown how they affect the prognosis of patients with lung cancer. This population-based study aimed to assess the incidence, associated factors, treatment and prognosis of PM from lung cancer. Data from the Netherlands Cancer Registry were used. All patients diagnosed with lung cancer between 2008 and 2018 were included. Logistic regression analysis was performed to identify factors associated with the presence of PM. Cox regression analysis was performed to identify factors associated with the overall survival (OS) of patients with PM. Between 2008 and 2018, 129,651 patients were diagnosed with lung cancer, of whom 2533 (2.0%) patients were diagnosed with PM. The European Standardized Rate of PM increased significantly from 0.6 in 2008 to 1.4 in 2018 (p < 0.001). Age between 50 and 74 years, T3-4 tumour stage, N2-3 nodal stage, tumour morphology of a small cell lung cancer or adenocarcinoma, and the presence of systemic metastases were associated with the presence of PM. The median OS of patients with PM was 2.5 months. Older age, male sex, T3-4 tumour stage, N2-3 nodal stage, not receiving systemic treatment, and the presence of systemic metastases were associated with a worse OS. Synchronous PM were diagnosed in 2.0% of patients with lung cancer and resulted in a very poor survival.

Differences in Sociodemographic Disparities Between Patients Undergoing Surgery for Advanced Colorectal or Ovarian Cancer

BACKGROUND

Cytoreductive surgery (CRS) for ovarian cancer with peritoneal metastases (OPM) is an established treatment, yet access-related racial and socioeconomic disparities are well documented. CRS for colorectal cancer with peritoneal metastases (CRPM) is garnering more widespread acceptance, and it is unknown what disparities exist with regards to access.

METHODS

This retrospective cross-sectional multicenter study analyzed medical records from the National Cancer Database from 2010 to 2015. Patients diagnosed with CRPM or ORP only and either no or confirmed resection were included. Patient- and facility-level characteristics were analyzed using uni- and multivariable logistic regressions to identify associations with receipt of CRS.

RESULTS

A total of 6634 patients diagnosed with CRPM and 14,474 diagnosed with OPM were included in this study. Among patients with CRPM, 18.1% underwent CRS. On multivariable analysis, female gender (odds ratio [95% CI] 2.04 [1.77-2.35]; P < 0.001) and treatment at an academic or research facility (OR 1.55 [1.17-2.05]; P = 0.002) were associated with CRS. Among patients with OPM, 87.1% underwent CRS. On multivariable analysis, treatment at facilities with higher-income patient populations was positively associated with CRS, while age (OR 0.97 [0.96-0.98]; P < .0001), use of nonprivate insurance (OR 0.69 [0.56-0.85]; P = 0.001), and listed as Black (OR 0.62 [0.45-0.86]; P = 0.004) were negatively associated with CRS.

CONCLUSION

There were more systemic barriers to CRS for patients with OPM than for patients with CRPM. As CRS becomes more widely practiced for CRPM, it is likely that more socioeconomic and demographic barriers will be elucidated.

Systemic therapy in addition to cytoreduction and hyperthermic intraperitoneal chemotherapy for colorectal peritoneal metastases: recent insights from clinical studies and translational research

There is a lack of randomized or high-quality intention-to-treat cohort studies addressing the role of systemic therapy in addition to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) as part of the treatment of colorectal peritoneal metastases (PM). Therefore, the choice whether or not to treat patients with systemic therapy is currently mainly based on expert opinion. As a result, treatment with neoadjuvant and/or adjuvant systemic therapy is implemented in various ways around the world. The aim of this review was to provide an overview of recent insights with regard to the systemic treatment of PM of colorectal origin obtained from clinical studies and translational research.

CA125, CEA, CA19-9, and Heteroploid Cells in Ascites Fluid May Help Diagnose Peritoneal Carcinomatosis in Patients with Gastrointestinal and Ovarian Malignancies

Background

This study explored the value of ascites and serum CA125, CEA, and CA19-9 levels and ascites DNA ploidy analysis for the diagnosis of peritoneal carcinomatosis (PC) in patients with gastrointestinal and ovarian malignancies, which can cause ascites and may disseminate peritoneally.

Methods

We measured ascites and serum levels of CA125, CEA, CA19-9 and performed an ascites DNA ploidy analysis in 58 patients with PC and 44 patients without PC.

Results

We found that a high expression level of CA125 in ascites fluid was associated with the occurrence of PC in patients with gastrointestinal and ovarian malignancies (P<0.001), and that high CEA and CA19- 9 levels in ascites fluid were associated with PC in patients with gastrointestinal malignancies (P=0.001, P=0.002). But, these tumor marker expression levels in ascites fluid were not significantly associated with the PC stage (P>0.05). We found similar serum levels of CA125, CEA, and CA19-9 between patients with gastrointestinal and ovarian malignancies and PC and those without PC (P>0.05). We found that the presence of three or more cells with heteroploid in the ascites samples was significantly associated with PC in gastrointestinal and ovarian malignancies (P<0.001). In addition, the best ROC curves and highest AUCs were achieved by combining the CA125 level and heteroploid cell analysis results (AUC for gastrointestinal and ovarian malignancies, 0.815, AUC for gastrointestinal malignancies, 0.873). Moreover, the combined ascites CA125 level and result of heteroploid cell analysis provided the best diagnostic sensitivity and specificity for PC (75.9% and 79.5%, respectively, in gastrointestinal and ovarian malignancies; 85.0% and 86.7%, respectively, in gastrointestinal malignancies).

Conclusion

Ascites levels of CA125, CEA, CA19-9, and heteroploid cells can be considered valuable markers for the diagnosis of PC in patients with gastrointestinal and ovarian cancer.

Immune response activation following hyperthermic intraperitoneal chemotherapy for peritoneal metastases: A pilot study

BACKGROUND

Hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal metastases (PM) is considered to be feasible, safe and to improve survival.

AIM

To investigate whether an immune response is activated following HIPEC for PM.

METHODS

Six patients were enrolled in this study. Peripheral blood samples were obtained from each patient prior to (day 0) and post-procedure (day 30), and used to evaluate the number of CD3⁺ total, CD3⁺/CD4⁺ T-Helper, CD3⁺/CD8⁺ cytotoxic T, CD3⁺/CD56⁺ natural killer and CD19⁺ B lymphocyte numbers, and CD4⁺: CD8⁺ T lymphocyte ratios.

RESULTS

The total numbers of CD3⁺, CD3⁺/CD4⁺ T-Helper, CD3⁺/CD8⁺ cytotoxic T, CD3⁺/CD56⁺ natural killer and CD19⁺ B lymphocytes, and CD4⁺: CD8⁺ lymphocyte ratios were increased in all but one patient 30 d following the cytoreductive surgery-HIPEC procedure, and these increases were significant (P ≤ 0.05) for CD3⁺/CD4⁺ T Helper and CD3⁺/CD8⁺ cytotoxic T lymphocyte numbers.

CONCLUSION

This report provides the first evidence that HIPEC exhibits immunomodulating activity in PM patients, resulting in generalized activation of the adaptive immune response. Moreover, the majority of lymphocyte populations increased following HIPEC and continued to be elevated several weeks following the procedure, consistent with a potential authentic immunomodulating effect rather than a normal inflammatory response, to be fully characterised in future studies.

Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC)-directed treatment of peritoneal metastasis in end-stage colo-rectal cancer patients

Background

Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) represents a novel approach to intraperitoneal chemotherapy. Hereby results, obtained with PIPAC in patients with advanced peritoneal metastasis (PM) from colorectal cancer (CRC), are presented.

Methods

Data from CRC patients (n = 24) included in the prospective PIPAC-OPC1 and PIPAC-OPC2 trials are reported. Oxaliplatin 92 mg/m² was administered at 4-6-week intervals. A CE certified nebulizer was used to aerosolize the chemotherapeutics. Outcome criteria were objective tumor response, survival and adverse events.

Results

Retrospective analysis of 74 PIPAC procedures carried out in 24 consecutive patients with PM from CRC included from October 2015 to February 2019. Five patients had still the primary tumor in situ, and 22 patients had received palliative systemic chemotherapy. Nineteen patients completed more than two PIPAC procedures, and objective tumor response according to the histological Peritoneal Regression Grading Score (PRGS) was observed in 67% of the patients, while 21% had stable disease. Four patients (21%) had complete response (mean PRGS = 1 and negative cytology). We recorded a median survival of 37.6 (range 7.3–48.9) months from the time of PM diagnosis, whereas it was 20.5 (range 0.13–34.7) months following the first PIPAC session. Minor postoperative complications were noted, and few were considered causally related to the PIPAC treatment. However, two cases of severe postoperative complications were recorded (urosepsis and iatrogenic bowel perforation).

Conclusions

PIPAC with low-dose oxaliplatin can induce objective tumor regression in selected patients with advanced PM from colorectal cancer.

Long-term survival after hyperthermic intraperitoneal chemotherapy using mitomycin C or oxaliplatin in colorectal cancer patients with synchronous peritoneal metastases: A nationwide comparative study

OBJECTIVES

In the Netherlands, limited variability exists in performance of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) among centers treating colorectal peritoneal metastases (PM), except for the intraperitoneal drug administration. This offers a unique opportunity to investigate any disparities in survival between the two most frequently used HIPEC regimens worldwide: mitomycin C (MMC) and oxaliplatin.

METHODS

This was a comparative, population-based cohort study of all Dutch patients diagnosed with synchronous colorectal PM who underwent CRS-HIPEC between 2014 and 2017. They were retrieved from the Netherlands Cancer Registry. Main outcome was overall survival (OS). The effect of the intraperitoneal drug on OS was investigated using multivariable Cox regression analysis.

RESULTS

In total, 297 patients treated between 2014 and 2017 were included. Among them, 177 (59.6%) received MMC and 120 (40.4%) received oxaliplatin. Only primary tumor location was different between the two groups: more left-sided colon in the Oxaliplatin group (47.5% vs. 33.3%, respectively, p=0.048). The 1-, 2- and 3-year OS were 84.6% vs. 85.8%, 61.6% vs. 63.9% and 44.7% vs. 53.5% in patients treated with MMC and oxaliplatin, respectively. Median OS was 30.7 months in the MMC group vs. 46.6 months in the oxaliplatin group (p=0.181). In multivariable analysis, no influence of intraperitoneal drug on survival was observed (adjusted HR 0.77 [0.53-1.13]).

CONCLUSIONS

Long-term survival between patients treated with either MMC or oxaliplatin during CRS-HIPEC was not significantly different.

The role of the peritoneal microenvironment in the pathogenesis of colorectal peritoneal carcinomatosis

Recent insights have implicated mesothelial-to-mesenchymal transition (MMT) as a mechanism by which mesothelial cells can transdifferentiate into cancer-associated fibroblasts (CAFs) in several cancers metastasizing to the peritoneum. However, this was not evaluated extensively in colorectal cancer. We examined the presumed mesothelial origin of CAFs in three types of colorectal carcinoma: conventional type adenocarcinoma, mucinous carcinoma and signet ring cell carcinoma. We evaluated the expression of mesothelial, mesenchymal, angiogenesis and colorectal cancer-related markers in peritoneal samples of twelve colorectal cancer patients with peritoneal carcinomatosis and four control patients by immunohistochemistry. We observed morphological and immunohistochemical changes in the vicinity of tumor implants in all studied colorectal cancer types. Mesothelial cells acquired a spindle-shaped myofibroblast-like morphology, lost expression of mesothelial markers, and gained expression of mesenchymal markers. Analysis of consecutive tissue sections and double staining for mesothelial and mesenchymal markers revealed overlap in expression of mesothelial and CAF markers. These findings are highly suggestive of a mesothelial origin of CAFs in peritoneal carcinomatosis in colorectal cancer. Interfering with the process of MMT might be a valuable approach in treating and preventing peritoneal carcinomatosis. Differences observed between colorectal cancer types suggest that one single strategy might not be applicable.

Peritoneal Cancers and Hyperthermic Intraperitoneal Chemotherapy

Cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy is an aggressive, potentially curative approach used to treat locoregional disease associated with primary and secondary malignancies of the peritoneum. It involves resection of all macroscopic disease larger than 2.5 mm, followed by instillation of hyperthermic chemotherapy directly into the peritoneum for higher drug exposure to microscopic disease. In select patients with primary peritoneal mesothelioma, pseudomyxoma peritonei, colorectal adenocarcinoma, appendiceal adenocarcinoma, or ovarian cancer, with no extra-abdominal metastasis and limited involvement of the peritoneum, the procedure can be performed to increase overall survival.

Overall risk and risk factors for metachronous peritoneal metastasis after colorectal cancer surgery: a nationwide cohort study

Background

This study aimed to identify the cumulative incidence and risk factors of metachronous peritoneal metastasis (M‐PM) from colorectal cancer in patients who had intended curative treatment.

Methods

Patients with colorectal cancer were identified using the Danish Colorectal Cancer Group database for 2006–2015. The Danish Pathology Registry and the Danish National Patient Registry were used to identify M‐PM to 2017. Risk factors were estimated by multivariable absolute risk regression, treating death and other cancers as competing risks. Overall risk and risk differences (RDs) were estimated at 1, 3 and 5 years.

Results

In 22 586 patients with colorectal cancer, the overall risk of M‐PM was reported to be 0·9 (95 per cent c.i. 0·8 to 1·0) per cent at 1 year, 1·9 (1·8 to 2·1) per cent at 3 years and 2·2 (2·0 to 2·4) per cent at 5 years. Advanced tumour category ((y)pT4 versus (y)pT1) increased the RD of both M‐PM (2·9 (95 per cent c.i. 2·1 to 3·7) at 1 year and 6·0 (4·9 to 7·2) at 3 years) and lymph node involvement ((y)pN2 versus (y)pN0) (2·5 (1·8 to 3·2) at year and 4·3 (3·2 to 5·3) at 3 years). No further increase in risk was observed at 5 years. In a subanalysis, tumour‐involved resection margin (R1 versus R0) was associated with M‐PM with a RD of 3·9 (1·6 to 6·2) at 1 year and 5·9 (2·6 to 9·3) at 3 years.

Conclusion

The overall risk of M‐PM in patients with colorectal cancer is low, but is increased in advanced T and N status. Follow‐up of at least 3 years after colorectal cancer surgery may be necessary, given the potential curative treatment of early diagnosed M‐PM.

Hypotonic stress enhances colon cancer cell death induced by platinum derivatives and immunologically improves antitumor efficacy of intraperitoneal chemotherapy

Colorectal cancer is a highly metastatic disease that could invade various distal organs and also the peritoneal cavity leading to peritoneal carcinomatosis. This is a terminal condition with poor prognosis and only palliative treatments such as cytoreductive surgery and intraperitoneal chemotherapy are proposed to some patients. However, clinicians use different parameters of treatments without any consensus. Here we decided to evaluate the effect of osmolarity in the efficacy of this procedure to kill colon cancer cells. We first show that a short exposure of platinum derivatives in hypotonic conditions is more efficient to decrease cell viability of human and murine colon cancer cells in vitro as compared to isotonic conditions. This is related to more important incorporation of platinum and the capacity of hypotonic stress to induce the copper transporter CTR1 oligomerization. Oxaliplatin in hypotonic conditions induces caspase-dependent cell death of colon cancer cells. Moreover, hypotonic conditions also modulate the capacity of oxaliplatin and cisplatin (but not carboplatin) to induce immunogenic cell death (ICD). In vivo, oxaliplatin in hypotonic conditions increases CD8⁺ T cell tumor infiltration and activation. Finally, in a murine peritoneal carcinomatosis model, oxaliplatin in hypotonic conditions is the only tested protocol which is able to slow down the appearance of tumor nodules and increase mice survival, while showing no effect in CD8⁺ T cells depleted mice or in immunodeficient mice. Altogether, our study provides new information both in vitro and in a preclinical model of peritoneal carcinomatosis, which highlights the importance of hypoosmolarity in intraperitoneal chemotherapy.

Trends in peritoneal surface malignancies: evidence from a Czech nationwide population-based study

Background

The aim of this study is to identify the incidence trends of primary and secondary peritoneal surface malignancies in a representative Czech population.

Methods

Data were obtained from patients registered in the Czech National Cancer Registry between 1979 and 2016. The incidence rates were analyzed between 2012 and 2016. To observe the incidence trends, we analyzed the data from two time periods, 1979–2005 and 2006–2016. The analyzed data included age, sex, and the histological types and primary origins of the malignancies. The Cochrane-Armitage test for linear trends was used for verification of the null hypothesis. The significance level established for hypothesis testing was p = 0.05.

Results

Between 2012 and 2016, 230 patients with primary peritoneal tumors were identified and divided into the following groups according to their “International Statistical Classification of Diseases and Related Health Problems, 10th revision” codes: malignant neoplasm of specified parts of the peritoneum (C48.1); malignant neoplasm of the peritoneum, unspecified (C48.2); and malignant neoplasm of overlapping sites of the retroperitoneum and peritoneum (C48.8). Moreover, 549 primary tumors of the appendix (C18.1, encompassing all appendiceal malignancies) and 3137 secondary synchronous peritoneal carcinomatoses of other primary origins were documented. The age-adjusted incidence of primary peritoneal tumors in 2012–2016 was 4.36/year/1,000,000 inhabitants. The age-adjusted incidence of synchronous secondary peritoneal malignancies in 2014–2016 was 99.0/year/1,000,000 inhabitants. The diagnoses of primary peritoneal malignancies followed a stable trend between 1979 and 2016. However, the incidences of primary tumors of the appendix increased by 76.7%.

Conclusions

The data produced in our study ought to clarify the status of peritoneal surface malignancies in the Czech Republic, which can lead to improved planning and development of therapeutic interventions as well as physician training.

Diagnostic Nodes of Patient Selection for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Among Colorectal Cancer Patients: A Swiss National Multicenter Survey

BACKGROUND

The management of patients with colorectal cancer (CRC) with peritoneal metastases is challenging, and the roles of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are unclear and debated among experts.

MATERIALS AND METHODS

The experts of the Swiss Peritoneal Cancer Group were contacted and agreed to participate in this analysis. Experts from 9 centers in Switzerland provided their decision algorithms for CRS/HIPEC for patients with or at high risk for peritoneal metastases from CRC. Their responses were converted into decision trees on the basis of objective consensus methodology. The decision trees were used as a basis to identify consensus and discrepancies.

RESULTS

The final treatment algorithms included a total of 5 decision criteria (age, Peritoneal Cancer Index [PCI], extraperitoneal metastases, Peritoneal Surface Disease Severity Score, and various risk factors [RF]) and 2 treatment options (HIPEC, yes or no). HIPEC was never recommended for patients without peritoneal metastases in the absence of RF for peritoneal metastases. For patients with a PCI ≤15 without organ metastases, all centers recommended CRS/HIPEC. There was also a consensus not to perform CRS/HIPEC in elderly patients (80 years and older), those with a PCI >20, and those with unresectable metastases. For patients with a PCI = 16 to 20, there was no consensus.

CONCLUSION

Multiple decision criteria relevant to all participating centers were identified. Because patient selection for CRS/HIPEC remains difficult, uniform criteria for the term "high risk" for peritoneal metastases and systemic metastases are helpful. Future trials and guidelines should take these criteria into account.

Hyperthermic intraperitoneal chemotherapy with cisplatin and mitomycin C for colorectal cancer peritoneal metastases: A systematic review of the literature

BACKGROUND

The randomized trial PRODIGE 7 failed to show the benefit of oxaliplatin hyperthermic intraperitoneal chemotherapy (HIPEC) in colorectal peritoneal metastasis treatment (CR PM). This systematic review focuses on the association of cisplatin (CDDP) with mitomycin C (MMC) in HIPEC in CR PM.

CONTENT

Experimental studies demonstrated that hyperthermia, in addition to CDDP ± MMC treatment, gradually improved the cytotoxic effect by increasing early apoptosis, eATP interaction, intracellular CDDP concentration (by 20%) and p73 expression. Recent studies with highly selected patients reported unusual prolonged survival with a median overall survival (OS) of approximately 60 months, with a HIPEC combination of CDDP (25 mg/m2/L) plus MMC (3.3 mg/m2/L) at a temperature of 41.5-42.5 °C for 60-90 min. Major complications occurred in less than 30% of patients with limited hematological toxicity (less than 15%). In addition, in a phase 2 trial, an adjuvant HIPEC benefit was demonstrated in colorectal cancer patients with high risk for peritoneal failure (5-year OS: 81.3% vs. 70% for the HIPEC group vs. the control group, respectively, p=0.047). After a recurrence, an iterative procedure permitted similar recurrence-free disease (13 vs. 13.7 months) with an acceptable morbidity (18.7% of severe complications).

SUMMARY AND OUTLOOK

The combination of CDDP and MMC seems to be an interesting protocol as an alternative to high-dose and short-term oxaliplatin.

Synchronous liver metastases and peritoneal carcinomatosis from colorectal cancer: different strategies for curative treatment?

BACKGROUND

Management of patients with resectable hepatic metastases (HMs) and colorectal peritoneal carcinomatosis (CRPC) is not currently standardised.

OBJECTIVE

The aims of this study were to evaluate the safety of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) and hepatic surgery for patients with CRPC with synchronous hepatic metastases (HM), and its impact on survival rates.

METHODS

A retrospective analysis was performed, including patients undergoing CRS/HIPEC for CRPC from 2007 to September 2016 in two groups, with (HM+) and without (HM-) synchronous hepatic metastases. Patients with extra-abdominal metastases were excluded. The hepatic strategy was described. Morbimortality and survival were compared between the two groups.

RESULTS

One hundred nine patients underwent CRS/HIPEC for CRPC with or without hepatic surgery with curative intent: 33 patients with (HM+) and 76 patients without (HM-) synchronous HM. The median follow-up was 30 months. All patients with HM (HM+) received neoadjuvant chemotherapy vs. 88.1% in the HM- group (p = 0.04) associated with monoclonal antibody in 66.6% of cases in the HM+ group vs. 57% in the HM- group (p = 0.01). In the HM+ group, two steps were implemented to treat peritoneal and hepatic metastases in 15 patients (45%). In this group, planned hepatic resection in two procedures was performed for eight patients, all presenting bilobar HM. Postoperative morbidity did not differ between the two groups. No deaths occurred. Median overall survival (OS) and recurrence-free survival (RFS) were 31 and 65 months (p = 0.188), versus 21 and 24 months (p = 0.119), respectively, in the HM+ versus HM- groups. In multivariate analysis, the peritoneal cancer index (PCI) was the only significant prognostic factor whereas synchronous HM was not a significant prognostic factor.

CONCLUSION

Curative surgical treatment for CRPC with synchronous HM seems to be feasible and safe, and could facilitate long survival rates, compared to patients without HM. The hepatic strategy is not standardised. However, a "two-step" surgical strategy could be proposed in order to reduce postoperative morbidity rates.

Second and third look laparoscopy in pT4 colon cancer patients for early detection of peritoneal metastases; the COLOPEC 2 randomized multicentre trial

Background

Approximately 20–30% of patients with pT4 colon cancer develop metachronous peritoneal metastases (PM). Due to restricted accuracy of imaging modalities and absence of early symptoms, PM are often detected at a stage in which only a quarter of patients are eligible for curative intent treatment. Preliminary findings of the COLOPEC trial (NCT02231086) revealed that PM were already detected during surgical re-exploration within two months after primary resection in 9% of patients with pT4 colon cancer. Therefore, second look diagnostic laparoscopy (DLS) to detect PM at a subclinical stage may be considered an essential component of early follow-up in these patients, although this needs confirmation in a larger patient cohort. Furthermore, a third look DLS after a negative second look DLS might be beneficial for detection of PM occurring at a later stage.

Methods

The aim of this study is to determine the yield of second look DLS and added value of third look DLS after negative second look DLS in detecting occult PM in pT4N0-2 M0 colon cancer patients after completion of primary treatment. Patients will undergo an abdominal CT at 6 months postoperative, followed by a second look DLS within 1 month if no PM or other metastases not amenable for local treatment are detected. Patients without PM will subsequently be randomized between routine follow-up including 18 months abdominal CT, or an experimental arm with a third look DLS provided that PM or incurable metastases are absent at the 18 months abdominal CT. Primary endpoint is the proportion of PM detected after a negative second look DLS and will be determined at 20 months postoperative.

Discussion

Second look DLS is supposed to result in 10% occult PM, and third look DLS after negative second look DLS is expected to detect an additional 10% of PM compared to routine follow-up alone in patients with pT4 colon cancer. Detection of PM at an early stage will likely increase the proportion of patients eligible for curative intent treatment and subsequently improve survival, given the uniformly reported direct association between the extent of peritoneal disease and survival.

Trial registration

ClinicalTrials.gov: NCT03413254, January 2018.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5408-8) contains supplementary material, which is available to authorized users.

Metastatic Profile of Colorectal Cancer: Interplay Between Primary Tumor Location and KRAS Status

BACKGROUND

Mutant KRAS tumors are purported to metastasize differently than wild-type KRAS tumors. The biological heterogeneity of tumors from different parts of the colon are also reported to affect metastasis. This study aims to characterize the metastatic profile by evaluating these factors in unison.

METHODS

Retrospective analysis of 899 patients with metastatic colorectal cancers treated from January 2010 to December 2014 was conducted. KRAS mutation status and primary tumors location were correlated with single-site metastasis (liver, lung, and peritoneum) and dual-site metastases (liver-peritoneum, liver-lung, and lung-peritoneum). Patients without KRAS analyses were excluded.

RESULTS

Right-sided tumors had highest frequency of peritoneal metastasis as compared to left-sided or rectal tumors (34.7% versus 15.8% versus 8.8%, P = 0.00) regardless of KRAS status (32.6% versus 38.5%, P = 0.62). Left-sided tumors with wild-type KRAS had greater proportion of liver metastasis (78.6% versus 53.5%, P = 0.00), whereas those with mutant KRAS had greater proportion of lung metastasis (23.3% versus 8.7%, P = 0.02). Rectal tumors with wild-type KRAS tend to spread to the liver (81.4% versus 48.0%, P = 0.00) and not to the peritoneum (2.3% versus 20.0%, P = 0.01). In dual-site metastases, left-sided tumors with wild-type KRAS had more liver-peritoneal metastases (75.0% versus 29.4%, P = 0.00), whereas mutant KRAS had greater lung-liver metastases (64.7% versus 20.8%, P = 0.01). Rectal tumors had the predilection for lung-liver metastases as compared to right-sided and left-sided tumors (92.3% versus 40.0% versus 39.0%, P = 0.00) regardless of KRAS status (100% versus 75%, P = 0.12).

CONCLUSIONS

Our results may streamline surveillance programs based on primary tumor location and KRAS mutational status.

The scientific report from the first pressurized intraperitoneal aerosol chemotherapy (PIPAC) procedures performed in the eastern part of Central Europe

Objective To perform a single-centre, detailed analysis of the preparations for the introduction of the first pressurized intraperitoneal aerosol chemotherapy (PIPAC) programme in the eastern part of Central Europe. Methods The study analysed the 14-month preparation period prior to the performance of the first PIPAC procedure with respect to: (i) general preparations; (ii) patient referral and qualification; (iii) the first PIPAC procedure; (iv) the 2 weeks following PIPAC programme establishment; and (v) general problematic issues that arose. Results The length of time needed to prepare our institution for the first PIPAC procedure was extremely long compared with other European Union PIPAC centres: 14 months versus a standard 3-6 months of preparation. The longest amount of time (12 months) was required to prepare the required paperwork. Conclusions A new PIPAC programme was successfully established in the eastern part of Central Europe. The length of time to implement this method was significantly longer because of lengthy bureaucratic processes. These current findings should help new centres, especially in this part of Europe, to establish a PIPAC programme more quickly.

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) and its receptor PROKR2 are associated to human colorectal cancer progression and peritoneal carcinomatosis

BACKGROUND

The highest risk factor for mortality among malignant tumors is metastasis. Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic factor which biological activity is mediated via two G protein-coupled receptors, prokineticin receptor1 (PROKR1) and PROKR2. Recent studies suggested that EG-VEGF expression is deregulated in multiple cancers including colorectal cancer (CRC).

METHODS

Using distinctive CRC and peritoneal carcinomatosis (PC) cohorts and a corresponding control cohort, we determined the circulating levels of EG-VEGF and its in situ expression, and that of its related receptors.

RESULTS

Circulating EG-VEGF levels were significantly increased in patients with metastatic PC compared to CRC and control patients (p< 0.05). Furthermore, according to clinicopathologic examinations, local EG-VEGF expression correlated with higher tumor and nodal stages (p< 0.001) of CRC. EG-VEGF and PROKR2 were highly expressed in colorectal primary lesions compared to positive controls. PROKR1 expression was lower and did not change in tumor specimens. Also, EG-VEGF and its receptor PROKR2 were differentially expressed in the colorectal primary lesions and in the control groups.

CONCLUSION

Altogether these findings suggest that EG-VEGF/receptors system might be an important actor in the CRC progression into PC and might be involved in the ability of tumor cells to invade other organs. Circulating EG-VEGF could be proposed as a prognostic marker in human CRC and its progression into PC.

Competition of charge-mediated and specific binding by peptide-tagged cationic liposome-DNA nanoparticles in vitro and in vivo

Cationic liposome-nucleic acid (CL-NA) complexes, which form spontaneously, are a highly modular gene delivery system. These complexes can be sterically stabilized via PEGylation [PEG: poly (ethylene glycol)] into nanoparticles (NPs) and targeted to specific tissues and cell types via the conjugation of an affinity ligand. However, there are currently no guidelines on how to effectively navigate the large space of compositional parameters that modulate the specific and nonspecific binding interactions of peptide-targeted NPs with cells. Such guidelines are desirable to accelerate the optimization of formulations with novel peptides. Using PEG-lipids functionalized with a library of prototypical tumor-homing peptides, we varied the peptide density and other parameters (binding motif, peptide charge, CL/DNA charge ratio) to study their effect on the binding and uptake of the corresponding NPs. We used flow cytometry to quantitatively assess binding as well as internalization of NPs by cultured cancer cells. Surprisingly, full peptide coverage resulted in less binding and internalization than intermediate coverage, with the optimum coverage varying between cell lines. In, addition, our data revealed that great care must be taken to prevent nonspecific electrostatic interactions from interfering with the desired specific binding and internalization. Importantly, such considerations must take into account the charge of the peptide ligand as well as the membrane charge density and the CL/DNA charge ratio. To test our guidelines, we evaluated the in vivo tumor selectivity of selected NP formulations in a mouse model of peritoneally disseminated human gastric cancer. Intraperitoneally administered peptide-tagged CL-DNA NPs showed tumor binding, minimal accumulation in healthy control tissues, and preferential penetration of smaller tumor nodules, a highly clinically relevant target known to drive recurrence of the peritoneal cancer.