Exposure-response relationships for oxaliplatin-treated colon cancer cells. Anticancer Drugs. 2008;19:37-44. [PMID: 18043128 DOI: 10.1097/cad.0b013e3282f07791]

[Contribution of intraperitoneal chemotherapy in the treatment of colorectal peritoneal carcinoma. HIPEC, PIPAC, state of the art and future directions]

After more than a decade of good results using the combination of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in the treatment of peritoneal carcinosis of colorectal origin, the PRODIGE7 study, which specifically evaluated the role of HIPEC, failed to show any superiority in terms of overall and disease-free survival for the CRS+HIPEC combination compared with CRS alone. This study constituted a radical change in the knowledge and therapeutic attitudes observed to date. After reviewing the literature and the consensus of national and international experts, a synthesis is provided, together with an outlook on the questions raised and the therapeutic trials and innovations of the near future. An analysis of recent advances due to the advent of a new technique, PIPAC, is also proposed, as well as a review of current therapeutic trials in this field.

In vitro 3D microfluidic peritoneal metastatic colorectal cancer model for testing different oxaliplatin-based HIPEC regimens

Objectives

Treatment of colorectal peritoneal metastases with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) is still evolving. Conducting a randomized trial is challenging due to the high heterogeneity in the presentation of peritoneal disease and various surgical approaches. Biological research may facilitate more rapid translation of information into clinical practice. There is an emerging need for a preclinical model to improve HIPEC treatment protocols in terms of drug doses and treatment durations. The aim of the study is to design a tool that serves as an in vitro three-dimensional (3D) microfluidic peritoneal metastatic colorectal cancer model to test the efficacy of different HIPEC treatments.

Methods

We determined the effects of current therapy options using a 3D static disease model on human colon carcinoma cell lines (HCT 116) and transforming growth factor-β1 induced epithelial-to-mesenchymal transition (EMT) HCT 116 lines at 37 °C and 42 °C for 30, 60, and 120 min. We determined oxaliplatin's half maximal inhibitory concentrations in a 3D static culture by using viability assay. Clinical practices of HIPEC were applied in the developed model.

Results

EMT-induced HCT 116 cells were less sensitive to oxaliplatin treatment compared to non-induced cells. We observed increased cytotoxicity when increasing the temperature from 37 °C to 42 °C and extending the treatment duration from 30 to 120 min. We found that 200 mg/m2 oxaliplatin administered for 120 min is the most effective HIPEC treatment option within the framework of clinic applications.

Conclusions

The tool map provide insights into creating more realistic pre-clinical tools that could be used for a patient-based drug screening.

2022 Peritoneal Surface Oncology Group International Consensus on HIPEC Regimens for Peritoneal Malignancies: Colorectal Cancer

BACKGROUND

Selected patients with peritoneal metastases of colorectal cancer (PM-CRC) can benefit from potentially curative cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC), with a median overall survival (OS) of more than 40 months.

OBJECTIVE

The aims of this evidence-based consensus were to define the indications for HIPEC, to select the preferred HIPEC regimens, and to define research priorities regarding the use of HIPEC for PM-CRC.

METHODS

The consensus steering committee elaborated and formulated pertinent clinical questions according to the PICO (patient, intervention, comparator, outcome) method and assessed the evidence according to the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework. Standardized evidence tables were presented to an international expert panel to reach a consensus (4-point, weak and strong positive/negative) on HIPEC regimens and research priorities through a two-round Delphi process. The consensus was defined as ≥ 50% agreement for the 4-point consensus grading or ≥ 70% for either of the two combinations.

RESULTS

Evidence was weak or very weak for 9/10 clinical questions. In total, 70/90 eligible panelists replied to both Delphi rounds (78%), with a consensus for 10/10 questions on HIPEC regimens. There was strong negative consensus concerning the short duration, high-dose oxaliplatin (OX) protocol (55.7%), and a weak positive vote (53.8-64.3%) in favor of mitomycin-C (MMC)-based HIPEC (preferred choice: Dutch protocol: 35 mg/m2, 90 min, three fractions), both for primary cytoreduction and recurrence. Determining the role of HIPEC after CRS was considered the most important research question, regarded as essential by 85.7% of the panelists. Furthermore, over 90% of experts suggest performing HIPEC after primary and secondary CRS for recurrence > 1 year after the index surgery.

CONCLUSIONS

Based on the available evidence, despite the negative results of PRODIGE 7, HIPEC could be conditionally recommended to patients with PM-CRC after CRS. While more preclinical and clinical data are eagerly awaited to harmonize the procedure further, the MMC-based Dutch protocol remains the preferred regimen after primary and secondary CRS.

Recommendations for the optimal management of peritoneal metastases in patients with colorectal cancer: a TTD and GECOP-SEOQ expert consensus statement

Peritoneal metastases (PM) occur when cancer cells spread inside the abdominal cavity and entail an advanced stage of colorectal cancer (CRC). Prognosis, which is poor, correlates highly with tumour burden, as measured by the peritoneal cancer index (PCI). Cytoreductive surgery (CRS) in specialized centres should be offered especially to patients with a low to moderate PCI when complete resection is expected. The presence of resectable metastatic disease in other organs is not a contraindication in well-selected patients. Although several retrospective and small prospective studies have suggested a survival benefit of adding hyperthermic intraperitoneal chemotherapy (HIPEC) to CRS, the recently published phase III studies PRODIGE-7 in CRC patients with PM, and COLOPEC and PROPHYLOCHIP in resected CRC with high-risk of PM, failed to show any survival advantage of this strategy using oxaliplatin in a 30-min perfusion. Final results from ongoing randomized phase III trials testing CRS plus HIPEC based on mitomycin C (MMC) are awaited with interest. In this article, a group of experts selected by the Spanish Group for the Treatment of Digestive Tumours (TTD) and the Spanish Group of Peritoneal Oncologic Surgery (GECOP), which is part of the Spanish Society of Surgical Oncology (SEOQ), reviewed the role of HIPEC plus CRS in CRC patients with PM. As a result, a series of recommendations to optimize the management of these patients is proposed.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: Epithelial Ovarian Cancer

BACKGROUND AND AIM

We report the results of an international consensus on hyperthermic intraperitoneal chemotherapy (HIPEC) regimens for epithelial ovarian cancer (EOC) performed with the following goals: To define the indications for HIPEC To identify the most suitable HIPEC regimens for each indication in EOC To identify areas of future research on HIPEC To provide recommendations for some aspects of perioperative care for HIPEC METHODS: The Delphi technique was used with two rounds of voting. There were three categories of questions: evidence-based recommendations [using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system with the patient, intervention, comparator, and outcome (PICO) method], an opinion survey, and research recommendations.

RESULTS

Seventy-three (67.5%) of 108 invited experts responded in round I, and 68 (62.9%) in round II. Consensus was achieved for 34/38 (94.7%) questions. However, a strong positive consensus that would lead to inclusion in routine care was reached for only 6/38 (15.7%) questions. HIPEC in addition to interval cytoreductive surgery (CRS) received a strong positive recommendation that merits inclusion in routine care. Single-agent cisplatin was the only drug recommended for routine care, and OVHIPEC-1 was the most preferred regimen. The panel recommended performing HIPEC for a minimum of 60 min with a recommended minimum intraabdominal temperature of 41°C. Nephroprotection with sodium thiosulfate should be used for cisplatin HIPEC.

CONCLUSIONS

The results of this consensus should guide clinical decisions on indications of HIPEC and the choice and various parameters of HIPEC regimens and could fill current knowledge gaps. These outcomes should be the basis for designing future clinical trials on HIPEC in EOC.

Surgical Options for Peritoneal Surface Metastases from Digestive Malignancies-A Comprehensive Review

The peritoneum is a common site for the dissemination of digestive malignancies, particularly gastric, colorectal, appendix, or pancreatic cancer. Other tumors such as cholangiocarcinomas, digestive neuroendocrine tumors, or gastrointestinal stromal tumors (GIST) may also associate with peritoneal surface metastases (PSM). Peritoneal dissemination is proven to worsen the prognosis of these patients. Cytoreductive surgery (CRS), along with systemic chemotherapy, have been shown to constitute a survival benefit in selected patients with PSM. Furthermore, the association of CRS with hyperthermic intraperitoneal chemotherapy (HIPEC) seems to significantly improve the prognosis of patients with certain types of digestive malignancies associated with PSM. However, the benefit of CRS with HIPEC is still controversial, especially due to the significant morbidity associated with this procedure. According to the results of the PRODIGE 7 trial, CRS for PSM from colorectal cancer (CRC) achieved overall survival (OS) rates higher than 40 months, but the addition of oxaliplatin-based HIPEC failed to improve the long-term outcomes. Furthermore, the PROPHYLOCHIP and COLOPEC trials failed to demonstrate the effectiveness of oxaliplatin-based HIPEC for preventing peritoneal metastases development in high-risk patients operated for CRC. In this review, we discuss the limitations of these studies and the reasons why these results are not sufficient to refute this technique, until future well-designed trials evaluate the impact of different HIPEC regimens. In contrast, in pseudomyxoma peritonei, CRS plus HIPEC represents the gold standard therapy, which is able to achieve 10-year OS rates ranging between 70 and 80%. For patients with PSM from gastric carcinoma, CRS plus HIPEC achieved median OS rates higher than 40 months after complete cytoreduction in patients with a peritoneal cancer index (PCI) ≤6. However, the data have not yet been validated in randomized clinical trials. In this review, we discuss the controversies regarding the most efficient drugs that should be used for HIPEC and the duration of the procedure. We also discuss the current evidence and controversies related to the benefit of CRS (and HIPEC) in patients with PSM from other digestive malignancies. Although it is a palliative treatment, pressurized intraperitoneal aerosolized chemotherapy (PIPAC) significantly increases OS in patients with unresectable PSM from gastric cancer and represents a promising approach for patients with PSM from other digestive cancers.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: A Summary of Key Clinical Trials

The peritoneal cavity is a common site of metastatic spread from colorectal cancer (CRC). Patients with peritoneal metastases (PM) often have aggressive underlying tumor biology and poor survival. While only a minority of patients with CRC have potentially resectable disease, the high overall incidence of CRC makes management of PM a common clinical problem. In this population, cytoreductive surgery (CRS)-hyperthermic intraperitoneal chemotherapy (HIPEC) is the only effective therapy for appropriately selected patients. In this narrative review, we summarize the existing literature on CRS-HIPEC in colorectal PM. Recent prospective clinical trials have shown conflicting evidence regarding the benefit of HIPEC perfusion in addition to CRS. Current strategies to prevent PM in those at high-risk have been shown to be ineffective. Herein we will provide a framework for clinicians to understand and apply these data to treat this complex disease presentation.

GECOP-MMC: phase IV randomized clinical trial to evaluate the efficacy of hyperthermic intraperitoneal chemotherapy (HIPEC) with mytomicin-C after complete surgical cytoreduction in patients with colon cancer peritoneal metastases

BACKGROUND

The French PRODIGE 7 trial, published on January 2021, has raised doubts about the specific survival benefit provided by HIPEC with oxaliplatin 460 mg/m² (30 minutes) for the treatment of peritoneal metastases from colorectal cancer. However, several methodological flaws have been identified in PRODIGE 7, specially the HIPEC protocol or the choice of overall survival as the main endpoint, so its results have not been assumed as definitive, emphasizing the need for further research on HIPEC. It seems that the HIPEC protocol with high-dose mytomicin-C (35 mg/m²) is the preferred regime to evaluate in future clinical studies.

METHODS

GECOP-MMC is a prospective, open-label, randomized, multicenter phase IV clinical trial that aims to evaluate the effectiveness of HIPEC with high-dose mytomicin-C in preventing the development of peritoneal recurrence in patients with limited peritoneal metastasis from colon cancer (not rectal), after complete surgical cytoreduction. This study will be performed in 31 Spanish HIPEC centres, starting in March 2022. Additional international recruiting centres are under consideration. Two hundred sixteen patients with PCI ≤ 20, in which complete cytoreduction (CCS 0) has been obtained, will be randomized intraoperatively to arm 1 (with HIPEC) or arm 2 (without HIPEC). We will stratified randomization by surgical PCI (1-10; 11-15; 16-20). Patients in both arms will be treated with personalized systemic chemotherapy. Primary endpoint is peritoneal recurrence-free survival at 3 years. An ancillary study will evaluate the correlation between surgical and pathological PCI, comparing their respective prognostic values.

DISCUSSION

HIPEC with high-dose mytomicin-C, in patients with limited (PCI ≤ 20) and completely resected (CCS 0) peritoneal metastases, is assumed to reduce the expected risk of peritoneal recurrence from 50 to 30% at 3 years.

TRIAL REGISTRATION

EudraCT number: 2019-004679-37; Clinicaltrials.gov: NCT05250648 (registration date 02/22/2022, ).

Preclinical In Vivo-Models to Investigate HIPEC; Current Methodologies and Challenges

Simple Summary

Efficacy of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) depends on patient selection, tumor type, delivery technique, and treatment parameters such as temperature, carrier solution, type of drug, dosage, volume, and treatment duration. Preclinical research offers a powerful tool to investigate the impact of these parameters and to assists in designing potentially more effective treatment protocols and clinical trials. This study aims to review the objectives, methods, and clinical relevance of in vivo preclinical HIPEC studies found in the literature. In total, 60 articles were included in this study. The selected articles were screened on the HIPEC parameters. Recommendations are provided and possible pitfalls are discussed on the choice of type of animal and tumor model per stratified parameters and study goal. The guidelines presented in this paper can improve the clinical relevance and impact of future in vivo HIPEC experiments.

Abstract

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment modality for patients with peritoneal metastasis (PM) of various origins which aims for cure in combination with cytoreductive surgery (CRS). Efficacy of CRS-HIPEC depends on patient selection, tumor type, delivery technique, and treatment parameters such as temperature, carrier solution, type of drug, dosage, volume, and treatment duration. Preclinical research offers a powerful tool to investigate the impact of these parameters and to assist in designing potentially more effective treatment protocols and clinical trials. The different methodologies for peritoneal disease and HIPEC are variable. This study aims to review the objectives, methods, and clinical relevance of in vivo preclinical HIPEC studies found in the literature. In this review, recommendations are provided and possible pitfalls are discussed on the choice of type of animal and tumor model per stratified parameters and study goal. The guidelines presented in this paper can improve the clinical relevance and impact of future in vivo HIPEC experiments.

The impact of PRODIGE 7 on the current worldwide practice of CRS-HIPEC for colorectal peritoneal metastases: A web-based survey and 2021 statement by Peritoneal Surface Oncology Group International (PSOGI)

INTRODUCTION

The PRODIGE 7-trial investigated the additional value of Hyperthermic Intraperitoneal Chemotherapy (HIPEC) to cytoreductive surgery (CRS) for patients with colorectal peritoneal metastases (CPM). The results of PRODIGE 7 were presented at the 2018 ASCO meeting showing that 30 min oxaliplatin-based HIPEC did not improve overall survival. The current study investigated the impact of PRODIGE 7 on the worldwide practice of CRS and HIPEC.

MATERIALS AND METHODS

CRS-HIPEC experts from 19 countries were invited through the Peritoneal Surface Oncology Group International (PSOGI) to complete an online survey concerning the current CRS-HIPEC practice in their hospital and country, and were asked to appraise the effect of PRODIGE 7.

RESULTS

The survey was completed by 18/19 experts. Although their personal opinions of CRS-HIPEC were barely influenced by PRODIGE 7, they reported a substantial impact on daily practice. This included a switch towards Mitomycin-C based HIPEC-regimens and prolongation of HIPEC perfusion time, a reduction in the number of referrals from non-HIPEC centers, a reduction in national consensus, the removal of HIPEC from national guidelines, and a reduced reimbursement rate.

CONCLUSION

The PRODIGE 7 has had a major impact on the practice of CRS-HIPEC for CPM worldwide. HIPEC remains an attractive option with potential for control and eradication of disease and further studies into the optimal HIPEC-regimen are urgently needed. Meanwhile, given the complexity of the treatment of patients with CPM, and the proven benefits of optimal CRS, referral of patients with potentially resectable CPM to expert centers is recommended whilst the precise role of HIPEC is further evaluated.

Current Management of Appendiceal Neoplasms

Appendiceal neoplasms include a heterogeneous group of epithelial and nonepithelial tumors that exhibit varying malignant potential. This review article summarizes current diagnostic criteria, classification systems, and optimal therapeutic strategies for the five main histopathologic subtypes of appendiceal neoplasms. In particular, the management of epithelial appendiceal neoplasms has evolved. Although their treatment has historically been extrapolated from colon cancer, improved understanding of their unique histopathologic and molecular characteristics and a growing body of published clinical data support a more nuanced approach to their management.

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy versus cytoreductive surgery alone for colorectal peritoneal metastases (PRODIGE 7): a multicentre, randomised, open-label, phase 3 trial

BACKGROUND

The addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to cytoreductive surgery has been associated with encouraging survival results in some patients with colorectal peritoneal metastases who were eligible for complete macroscopic resection. We aimed to assess the specific benefit of adding HIPEC to cytoreductive surgery compared with receiving cytoreductive surgery alone.

METHODS

We did a randomised, open-label, phase 3 trial at 17 cancer centres in France. Eligible patients were aged 18-70 years and had histologically proven colorectal cancer with peritoneal metastases, WHO performance status of 0 or 1, a Peritoneal Cancer Index of 25 or less, and were eligible to receive systemic chemotherapy for 6 months (ie, they had adequate organ function and life expectancy of at least 12 weeks). Patients in whom complete macroscopic resection or surgical resection with less than 1 mm residual tumour tissue was completed were randomly assigned (1:1) to cytoreductive surgery with or without oxaliplatin-based HIPEC. Randomisation was done centrally using minimisation, and stratified by centre, completeness of cytoreduction, number of previous systemic chemotherapy lines, and timing of protocol-mandated systemic chemotherapy. Oxaliplatin HIPEC was administered by the closed (360 mg/m²) or open (460 mg/m²) abdomen techniques, and systemic chemotherapy (400 mg/m² fluorouracil and 20 mg/m² folinic acid) was delivered intravenously 20 min before HIPEC. All individuals received systemic chemotherapy (of investigators' choosing) with or without targeted therapy before or after surgery, or both. The primary endpoint was overall survival, which was analysed in the intention-to-treat population. Safety was assessed in all patients who received surgery. This trial is registed with ClinicalTrials.gov, NCT00769405, and is now completed.

FINDINGS

Between Feb 11, 2008, and Jan 6, 2014, 265 patients were included and randomly assigned, 133 to the cytoreductive surgery plus HIPEC group and 132 to the cytoreductive surgery alone group. After median follow-up of 63·8 months (IQR 53·0-77·1), median overall survival was 41·7 months (95% CI 36·2-53·8) in the cytoreductive surgery plus HIPEC group and 41·2 months (35·1-49·7) in the cytoreductive surgery group (hazard ratio 1·00 [95·37% CI 0·63-1·58]; stratified log-rank p=0·99). At 30 days, two (2%) treatment-related deaths had occurred in each group.. Grade 3 or worse adverse events at 30 days were similar in frequency between groups (56 [42%] of 133 patients in the cytoreductive surgery plus HIPEC group vs 42 [32%] of 132 patients in the cytoreductive surgery group; p=0·083); however, at 60 days, grade 3 or worse adverse events were more common in the cytoreductive surgery plus HIPEC group (34 [26%] of 131 vs 20 [15%] of 130; p=0·035).

INTERPRETATION

Considering the absence of an overall survival benefit after adding HIPEC to cytoreductive surgery and more frequent postoperative late complications with this combination, our data suggest that cytoreductive surgery alone should be the cornerstone of therapeutic strategies with curative intent for colorectal peritoneal metastases.

FUNDING

Institut National du Cancer, Programme Hospitalier de Recherche Clinique du Cancer, Ligue Contre le Cancer.

Oxaliplatin versus Mitomycin C following complete cytoreduction for colorectal peritoneal metastases: a comparative study

BACKGROUND AND OBJECTIVES

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) can offer selected patients with colorectal peritoneal metastases (CRPM) a favorable long-term survival. While cytoreductive techniques are standardized, there remains great variability in HIPEC drugs with mitomycin C or oxaliplatin use based largely on institute preference. In this study, we compared outcomes based on mitomycin C or oxaliplatin use after complete cytoreduction.

METHODS

This is a retrospective analysis over a 7-year period of all patients undergoing complete cytoreduction with HIPEC.

RESULTS

Seventy-eight patients underwent complete cytoreduction with HIPEC during this time. Forty-six patients received oxaliplatin as HIPEC, and 32 received mitomycin C. There was no difference in patient characteristics, resections, or major morbidity between the two groups. Superficial wound infections were higher in the mitomycin C group (37.5% v 15.2%, p = 0.02). Median overall and disease-free survival for the entire cohort was 40 and 14 months, respectively. There was no difference in overall survival or disease-free survival between the two HIPEC groups (HR 0.50, 95% CI 0.11-2.28).

CONCLUSION

Complete cytoreduction and HIPEC can offer selected patients a favorable survival. The choice of mitomycin C or oxaliplatin for HIPEC had no influence on survival. Prospective studies are needed to explore this important issue.

Experimental Treatment of Mucinous Peritoneal Metastases Using Patient-Derived Xenograft Models

Mucinous peritoneal metastases (PM) generally respond poorly to systemic treatment, and there is a clear unmet need for new treatment strategies to improve survival and quality of life for patients with PM. In this work, the growth inhibitory effect of five drugs (oxaliplatin (OXA; 5 mg/kg), irinotecan (IRI; 60 mg/kg), cabazitaxel (CBZ; 15 or 30 mg/kg), regorafenib (REG; 10, 30 or 60 mg/kg), and capecitabine (CAP; 359 or 755 mg/kg) was investigated in three orthotopic patient-derived xenograft models that mimic mucinous PM. Drugs were administered intraperitoneally (i.p.) as monotherapy weekly for 4 weeks (OXA, IRI), as one single i.p. injection (CBZ), or orally (REG, CAP) daily 5 of 7 days per week for four weeks, and i.p. tumor growth and survival were monitored and compared between treatment groups. The i.p. administered drugs (OXA, IRI, CBZ) had the strongest growth inhibitory effect, with OXA being most efficacious, completely inhibiting tumor growth in the majority of the animals. CBZ and IRI also strongly inhibited tumor growth, but with more variation in efficacy between the models. A moderate reduction in tumor growth was observed in all models treated with REG, while CAP had little to no growth inhibitory effect. Targeted next-generation-sequencing has identified mutational profiles typically associated with PM (mutations in KRAS, GNAS, and BRAF oncogenes), supporting the representativeness of the models. The results presented in this work support the continued exploration of i.p. treatment protocols for PM, with OXA remaining and CBZ emerging as particularly interesting candidates for further studies.

Personalized Identification of Optimal HIPEC Perfusion Protocol in Patient-Derived Tumor Organoid Platform

BACKGROUND

Chemotherapy dosing duration and perfusion temperature vary significantly in HIPEC protocols. This study investigates patient-derived tumor organoids as a platform to identify the most efficacious perfusion protocol in a personalized approach.

PATIENTS AND METHODS

Peritoneal tumor tissue from 15 appendiceal and 8 colon cancer patients who underwent CRS/HIPEC were used for personalized organoid development. Organoids were perfused in parallel at 37 and 42 °C with low- and high-dose oxaliplatin (200 mg/m² over 2 h vs. 460 mg/m² over 30 min) and MMC (40 mg/3L over 2 h). Viability assays were performed and pooled for statistical analysis.

RESULTS

An adequate organoid number was generated for 75% (6/8) of colon and 73% (11/15) of appendiceal patients. All 42 °C treatments displayed lower viability than 37 °C treatments. On pooled analysis, MMC and 200 mg/m² oxaliplatin displayed no treatment difference for either appendiceal or colon organoids (19% vs. 25%, p = 0.22 and 27% vs. 31%, p = 0.55, respectively), whereas heated MMC was superior to 460 mg/m² oxaliplatin in both primaries (19% vs. 54%, p < 0.001 and 27% vs. 53%, p = 0.002, respectively). In both appendiceal and colon tumor organoids, heated 200 mg/m² oxaliplatin displayed increased cytotoxicity as compared with 460 mg/m² oxaliplatin (25% vs. 54%, p < 0.001 and 31% vs. 53%, p = 0.008, respectively).

CONCLUSIONS

Organoids treated with MMC or 200 mg/m² heated oxaliplatin for 2 h displayed increased susceptibility in comparison with 30-min 460 mg/m² oxaliplatin. Optimal perfusion protocol varies among patients, and organoid technology may offer a platform for tailoring HIPEC conditions to the individual patient level.

Intraperitoneal chemotherapy for peritoneal metastases: an expert opinion

Introduction: The rationale for intraperitoneal (IP) drug delivery for patients with peritoneal metastases (PM) is based on the pharmacokinetic advantage resulting from the peritoneal-plasma barrier, and on the potential to adequately treat small, poorly vascularized PM. Despite a history of more than three decades, many aspects of IP drug delivery remain poorly studied.Areas covered: We outline the anatomy and physiology of the peritoneal cavity, including the pharmacokinetics of IP drug delivery. We discuss transport mechanisms governing tissue penetration of IP chemotherapy, and how these are affected by the biomechanical properties of the tumor stroma. We provide an overview of the current clinical evidence on IP chemotherapy in ovarian, colorectal, and gastric cancer. We discuss the current limitations of IP drug delivery and propose several potential areas of progress.Expert opinion: The potential of IP drug delivery is hampered by off-label use of drugs developed for systemic therapy. The efficacy of IP chemotherapy for PM depends on cancer type, disease extent, and mode of drug delivery. Results from ongoing randomized trials will allow to better delineate the potential of IP chemotherapy. Promising approaches include IP aerosol therapy, prolonged delivery platforms such as gels or biomaterials, and the use of nanomedicine.

HIPEC with oxaliplatin for colorectal peritoneal metastasis: The end of the road?

In patients with colorectal peritoneal metastases (PM), the use of cytoreductive surgery (CRS) and HIPEC with oxaliplatin (OX) is increasingly used. The results of the recently reported randomized Prodige 7 trial failed to show a difference in overall survival between patients undergoing CRS alone versus CRS combined with HIPEC using high dose OX. The trial was not designed or powered, however, to detect a potentially clinically meaningful benefit in locoregional disease control. Here, I address some potential explanations for the lack of benefit in the Prodige 7 trial, including OX efficacy issues, adverse effects of intraperitoneal high dose glucose, and potential drawbacks of the use of hyperthermia.

Narrow line between benefit and harm: Additivity of hyperthermia to cisplatin cytotoxicity in different gastrointestinal cancer cells

AIM

To investigate the response to hyperthermia and chemotherapy, analyzing apoptosis, cytotoxicity, and cisplatin concentration in different digestive system cancer cells.

METHODS

AGS (gastric cancer cell line), Caco-2 (colon cancer cell line) and T3M4 (pancreatic cancer cell line) were treated by cisplatin and different temperature setting (37 °C to 45 °C) either in isolation, or in combination. Treatment lasted for one hour. 48 h after the treatment viability was evaluated by MTT, cell apoptosis by Annexin V-PE and 7ADD flow cytometry. Intracellular cisplatin concentration was measured immediately after the treatment, using mass spectrometry. Isobologram analysis was performed to evaluate the mathematical combined effect of temperature and cisplatin.

RESULTS

AGS cells were the most sensitive to isolated application of hyperthermia. Hyperthermia, in addition to cisplatin treatment, did not provoke a synergistic effect at intervals from 37 °C to 41 °C in neither cancer cell line. However, a temperature of 43 °C enhanced cisplatin cytotoxicity for Caco-2 cells. Moreover, isobologram analysis revealed mathematical antagonistic effects of cisplatin and temperature combined treatment in AGS cells; variations between synergistic, additive, and antagonistic effects in Caco-2 cells; and additive and antagonistic effects in T3M4 cells. Combined treatment enhanced initiation of cell apoptosis in AGS, Caco-2, and T3M4 cells by 61%, 20%, and 19% respectively. The increase of intracellular cisplatin concentration was observed at 43 °C by 30%, 20%, and 18% in AGS, Caco-2, and T3M4 cells, respectively.

CONCLUSION

In addition to cisplatin, hyperthermia up to 43 °C does not affect the viability of cancer cells in a synergistic manner.

Thermotherapy enhances oxaliplatin-induced cytotoxicity in human colon carcinoma cells

AIM: To observe the synergistic effects of hyperthermia in oxaliplatin-induced cytotoxicity in human colon adenocarcinoma Lovo cells.

METHODS: The human colon adenocarcinoma cell line Lovo was obtained from Sun Yat-Sen University. Cells were sealed with parafilm and placed in a circulating water bath, and was maintained within 0.01  °C of the desired temperature (37  °C, 39  °C, 41  °C, 43  °C and 45  °C). Thermal therapy was given alone to the negative control group while oxaliplatin was administered to the treatment group at doses of 12.5 μg/mL and 50 μg/mL. Identification of morphological changes, 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry and Western blotting were used to investigate the effect of thermochemotherapy on human colon adenocarcinoma Lovo cells, including changes in the signal pathway related to apoptosis.

RESULTS: A temperature-dependent inhibition of cell growth was observed after oxaliplatin exposure, while a synergistic interaction was detected preferentially with sequential combination. Thermochemotherapy changed the morphology of Lovo cells, increased the inhibition rate of the Lovo cells (P < 0.05) and enhanced cellular population in the G₀/G₁ phase (16.7% ± 4.8 % in phase S plus 3.7% ± 2.4 % in phase G₂/M, P < 0.05). Thermochemotherapy increased apoptosis through upregulating p53, Bax and downregulating Bcl-2. Protein levels were elevated in p53, Bax/Bcl-2 in thermochemotherapy group as compared with the control group (P < 0.05).

CONCLUSION: Thermochemotherapy may play an important role in apoptosis via the activation of p53, Bax and the repression of Bcl-2 in Lovo cells.