Progression following neoadjuvant systemic chemotherapy may not be a contraindication to a curative approach for colorectal carcinomatosis. Ann Surg. 2012;256:125-129. [PMID: 22580942 DOI: 10.1097/sla.0b013e318255486a]

Systemic chemotherapy in addition to CRS-HIPEC for colorectal peritoneal metastases: A critical systematic review on the impact on overall survival

In patients with resectable colorectal peritoneal metastases, it is unclear whether systemic chemotherapy, in addition to cytoreductive surgery-hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), improves overall survival (OS). This systematic review of 12 retrospective studies involving 3721 patients aimed to summarize the available evidence. Contradictory results were found regarding the effectiveness of neoadjuvant, adjuvant, and perioperative systemic therapies on OS, with a high risk of bias. Available evidence remains inconclusive, stressing the need for prospective, randomized trials, like the ongoing Dutch CAIRO6-trial.

Role of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy in the Management of Colorectal Peritoneal Metastases

Peritoneal metastases from colon cancer are a particularly challenging disease process given the limited response to systemic chemotherapy. In patients with isolated peritoneal metastases, cytoreductive surgery with hyperthermic intraperitoneal chemotherapy offers a potential treatment option to these patients with limited peritoneal metastases as long as a complete cytoreduction is achieved. Decision about a patient's candidacy for this treatment modality should be undertaken by a multidisciplinary group at expert centers.

Predictive factors of non-completion of cytoreductive surgery in colorectal peritoneal metastasis

INTRODUCTION

Cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC) is the only potentially curative treatment that can improve the survival prognosis for patients with peritoneal metastasis (PM) of colorectal origin. The main independent prognostic factors are extent of disease, as measured by the Peritoneal Cancer Index (PCI), and completion of CRS (CC-0 or R1). Despite thorough preoperative work-up for selection of surgical candidates, 20%-25 % of CRS procedures are stopped after exploration during laparotomy. These patients undergo "open-and-close" procedures associated with a risk of complications and without any benefit. The aim of this study was to identify preoperative predictors of non-resectability and/or non-completion of CRS in patients with colorectal PMs who were candidates for surgery.

MATERIALS AND METHODS

Retrospective, monocentric study including patients admitted for CRS ± HIPEC at the Jules Bordet Institute between January 01, 2010 and December 31, 2021. The preoperative epidemiological, pathological, clinical, radiological, and biological features of patients with unresectable disease were compared with those of patients treated with CRS.

RESULTS

One hundred nineteen patients were included, 60 men and 59 women (median age 61 years). Twenty-one CRS procedures (17.65 %) were stopped during exploratory laparotomy. Statistically significant factors associated with non-completion were age (p = 0.0183), PCI (p = 0.0001), presence of sub/occlusive episode(s) prior to CRS (p = 0.0012), and multifocal-diffuse uptakes on PET-scan (p = 0.0017).

CONCLUSION

Almost 18 % of patients had an "open-and-close" procedure. PCI was the major determinant of non-completion of CRS. Other predictive factors of unresectability of colorectal PM were age, the presence of sub/occlusive episodes, and PET/CT with multiple peritoneal uptakes.

Outcomes of preoperative chemotherapy for colorectal cancer with peritoneal metastasis underwent cytoreductive surgery

BACKGROUND

This study aims to assess and compare the extent to which preoperative chemotherapy prior to CRS improves survival in patients diagnosed with CRCPM.

METHODS

We included 251 patients from 2012 to 2019 in our center. Inverse probability of treatment weighting (IPTW) analysis was used to minimize the selection bias. Survival analysis was performed to compare the survival outcomes. Multivariate Cox regression analysis was conducted to identify prognostic factors.

RESULT

The baseline characteristics were well balanced using IPTW (standardized mean difference < 0.1). Preoperative chemotherapy cannot significantly improve overall survival (HR, 1.03; 95% CI 0.71-1.49; P = 0.88). In subgroup analysis, we found that intestinal obstruction after preoperative chemotherapy significantly reduced survival (HR, 2.25; 95% CI 1.01-5.03; P = 0.048), while in the upfront surgery group, intestinal obstruction had no impact on prognosis.

CONCLUSION

For CRCPM patients treated with CRS, preoperative chemotherapy does not seem to prolong overall survival. Furthermore, the emergence of intestinal obstruction after chemotherapy may compromise the effectiveness of treatment, resulting in a worse prognosis. This finding has important clinical implications for treatment decisions.

Is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy still beneficial in patients diagnosed with colorectal peritoneal metastasis who underwent palliative chemotherapy?

BACKGROUND

With a 5-year overall survival of less than 5%, colorectal peritoneal metastasis (CPM) patients are often managed with palliative chemotherapy (CTx). In the past few decades, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been introduced as a possible curative treatment for highly selective CPM patients. We share our experience of CRS and HIPEC given the unique characteristics of the medical system and the benefit of CRS and HIPEC in palliative setting.

METHODS

From April 2017 to October 2021, CPM patients who underwent CRS and HIPEC were analyzed. Patients were allocated into perioperative and palliative CTx arm based on the duration between initial diagnosis of CPM to undergoing CRS and HIPEC of 6 months. Data including perioperative parameters, postoperative outcomes, and survival were analyzed with a median follow-up of 28.5 months.

RESULTS

Twenty-six CPM patients underwent CRS and HIPEC. Mean time from diagnosis of CPM to CRS and HIPEC was 5.5 months with 14 patients in the perioperative arm and 12 patients in the palliative arm. Perioperative group showed a longer RFS of 13.5 months compared to 8 months in the palliative group. Median overall survival of palliative group was 41.50 months, and 18 patients among all groups are alive at the time of this report.

CONCLUSION

CRS and HIPEC could be a treatment option for a carefully selected CPM patients performed by experienced surgeons. Overall survival of 41.50 months in palliative group compared to 16.8 months from conventional systemic CTx supports CRS and HIPEC even in palliative patients.

Is Systemic Chemotherapy Useful in Patients Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Colorectal Peritoneal Metastases? A Propensity-Score Analysis

PURPOSE

Multimodal treatment of colorectal (CRC) peritoneal metastases (PM) includes systemic chemotherapy (SC) and surgical cytoreduction (CRS), eventually with hyperthermic intraperitoneal chemotherapy (HIPEC), in select patients. Considering lack of clear guidelines, this study was designed to analyze the role of chemotherapy and its timing in patients treated with CRS-HIPEC.

METHODS

Data from 13 Italian centers with PM expertise were collected by a collaborative group of the Italian Society of Surgical Oncology (SICO). Clinicopathological variables, SC use, and timing of administration were correlated with overall survival (OS), disease-free survival (DFS), and local (peritoneal) DFS (LDFS) after propensity-score (PS) weighting to reduce confounding factors.

RESULTS

A total of 367 patients treated with CRS-HIPEC were included in the propensity-score weighting. Of the total patients, 19.9% did not receive chemotherapy within 6 months of surgery, 32.4% received chemotherapy before surgery (pregroup), 28.9% after (post), and 18.8% received both pre- and post-CRS-HIPEC treatment (peri). SC was preferentially administered to younger (p = 0.02) and node-positive (p = 0.010) patients. Preoperative SC is associated with increased rate of major complications (26.9 vs. 11.3%, p = 0.0009). After PS weighting, there were no differences in OS, DFS, or LDFS (p = 0.56, 0.50, and 0.17) between chemotherapy-treated and untreated patients. Considering SC timing, the post CRS-HIPEC group had a longer DFS and LDFS than the pre-group (median DFS 15.4 vs. 9.8 m, p = 0.003; median LDFS 26.3 vs. 15.8 m, p = 0.026).

CONCLUSIONS

In patients with CRC-PM treated with CRS-HIPEC, systemic chemotherapy was not associated with overall survival benefit. The adjuvant schedule was related to prolonged disease-free intervals. Additional, randomized studies are required to clarify the role and timing of systemic chemotherapy in this patient subset.

Intraperitoneal paclitaxel combined with FOLFOX/CAPOX plus bevacizumab for colorectal cancer with peritoneal carcinomatosis (the iPac-02 trial): study protocol of a single arm, multicenter, phase 2 study

BACKGROUND

The safety of intraperitoneally administrated paclitaxel (op PTX) was demonstrated in the phase I trial of ip PTX combined with conventional systemic chemotherapy for colorectal cancer with peritoneal carcinomatosis. Moreover, the median survival time was 29.3 months, which was longer than that observed in previous studies. Here, we planned the phase II trial of ip PTX: the iPac-02 trial.

METHODS

This multicenter, open-label, single assignment interventional clinical study includes patients with colorectal cancer with unresectable peritoneal carcinomatosis. FOLFOX-bevacizumab or CAPOX-bevacizumab is administered concomitantly as systemic chemotherapy. PTX 20 mg/m2 is administered weekly through the peritoneal access port in addition to these conventional systemic chemotherapies. The response rate is the primary endpoint. Progression-free survival, overall survival, peritoneal cancer index improvement rate, rate of negative peritoneal lavage cytology, safety, and response rate to peritoneal metastases are the secondary endpoints. A total of 38 patients are included in the study. In the interim analysis, the study will continue to the second stage if at least 4 of the first 14 patients respond to the study treatment. The study has been registered at the Japan Registry of Clinical Trials (jRCT2031220110).

RESULTS

We previously conducted phase I trial of ip PTX combined with conventional systemic chemotherapy for colorectal cancer with peritoneal carcinomatosis [1]. In the study, three patients underwent mFOLFOX, bevacizumab, and weekly ip PTX, and the other three patients underwent CAPOX, bevacizumab, and weekly ip PTX treatment. The dose of PTX was 20 mg/m [2]. The primary endpoint was the safety of the chemotherapy, and secondary endpoints were response rate, peritoneal cancer index improvement rate, rate of negative peritoneal lavage cytology, progression-free survival, and overall survival. Dose limiting toxicity was not observed, and the adverse events of ip PTX combined with oxaliplatin-based systemic chemotherapy were similar to those described in previous studies using systemic chemotherapy alone [3, 4]. The response rate was 25%, peritoneal cancer index improvement rate was 50%, and cytology in peritoneal lavage turned negative in all the cases. The progression-free survival was 8.8 months (range, 6.8-12 months), and median survival time was 29.3 months [5], which was longer than that observed in previous studies.

CONCLUSION

Here, we planned the phase II trial of ip paclitaxel combined with conventional chemotherapy for colorectal cancer with peritoneal carcinomatosis: the iPac-02 trial.

Influence of Extraperitoneal Metastases on the Curative-Intent Management of Colorectal Peritoneal Metastases

BACKGROUND

Selected patients with colorectal cancer peritoneal metastasis (CRPM) and extraperitoneal disease could be treated radically with a multimodal approach combining complete cytoreductive surgery, thermoablation, radiotherapy, and systemic and intraperitoneal chemotherapy. The impact of extraperitoneal metastatic sites (EPMS) in this setting remains unclear.

PATIENTS AND METHODS

Patients with CRPM undergoing complete cytoreduction in 2005-2018 were grouped in: peritoneal disease only (PDO), one EPMS (1 + EPMS), two or more EPMS (2 + EPMS). A retrospective analysis compared overall survival (OS) and postoperative outcomes.

RESULTS

Of 433 patients, 109 had 1 + EPMS and 31 had 2 + EPMS. Overall, 101 patients had liver metastasis, 19 lung metastasis, and 30 retroperitoneal lymph node (RLN) invasion. The median OS was 56.9 months. There was no significant OS difference between PDO and 1 + EPMS groups (64.6 and 57.9 months, respectively), whereas OS was lower in the 2 + EPMS group (29.4 months, p = 0.005). In multivariate analysis, 2 + EPMS [hazard ratio (HR) 2.86, 95% confidence interval (CI) 1.33-6.12, p = 0.007], Sugarbaker's Peritoneal Carcinomatosis Index (PCI) > 15 (HR 3.86, 95% CI 2.04-7.32, p < 0.001), poorly differentiated tumors (HR 2.62, 95% CI 1.21-5.66, p = 0.015), and BRAF mutation (HR 2.10, 95% CI 1.11-3.99, p = 0.024) were independent poor prognostic factors, while adjuvant chemotherapy was beneficial (HR 0.33, 95% CI 0.20-0.56, p < 0.001). Patients with liver resection did not show higher severe complication rates.

CONCLUSION

In patients with CRPM selected for a radical surgical approach, limited extraperitoneal disease involving one site, notably the liver, does not seem to significantly impair postoperative results. RLN invasion appeared as a poor prognostic factor in this population.

A total neoadjuvant chemotherapy approach is associated with improved recurrence-free survival in patients with colorectal peritoneal metastases undergoing cytoreductive surgery and HIPEC

BACKGROUND

The primary aim of this study is to evaluate the oncologic outcomes of two popular systemic chemotherapy approaches in patients with colorectal peritoneal metastases (CPM) undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC).

METHODS

We performed a dual-center retrospective review of consecutive patients who underwent CRS-HIPEC for CPM due to high or intermediate-grade colorectal cancer. Patients in the total neoadjuvant therapy (TNT) group received 6 months of preoperative chemotherapy. Patients in the "sandwich" (SAND) chemotherapy group received 3 months of preoperative chemotherapy with a maximum of 3 months of postoperative chemotherapy.

RESULTS

A total of 34 (43%) patients were included in the TNT group and 45 (57%) patients in the SAND group. The median overall survival (OS) in the TNT and SAND groups were 77 and 61 months, respectively (p = 0.8). Patients in the TNT group had significantly longer recurrence-free survival (RFS) than the SAND group (29 vs. 12 months, p = 0.02). In a multivariable analysis, the TNT approach was independently associated with improved RFS.

CONCLUSION

In this retrospective study, a TNT approach was associated with improved RFS, but not OS when compared with a SAND approach. Further prospective studies are needed to examine these systemic chemotherapeutic approaches in patients with CPM undergoing CRS-HIPEC.

Perioperative chemotherapy in colorectal cancer with peritoneal metastases: A global propensity score matched study

BACKGROUND

There is a paucity of studies evaluating perioperative systemic chemotherapy in conjunction with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with colorectal cancer peritoneal metastases (CRCPM). The aim was to evaluate neoadjuvant and/or adjuvant systemic therapy in CRCPM.

METHODS

Patients with CRCPM from 39 treatment centres globally from January 1, 1991, to December 31, 2018, who underwent CRS+HIPEC were identified and stratified according to neoadjuvant/adjuvant use. Crude data analysis, propensity score matching (PSM) and Cox-proportional hazard modelling was performed.

FINDINGS

Of 2093 patients, 1613 were included in neoadjuvant crude evaluation with 708 in the PSM cohort (354 patients/arm). In the adjuvant evaluation, 1176 patients were included in the crude cohort with 778 in the PSM cohort (389 patients/arm). The median overall survival (OS) in the PSM cohort receiving no neoadjuvant vs neoadjuvant therapy was 37.0 months (95% CI: 32.6-42.7) vs 34.7 months (95% CI: 31.2-38.8, HR 1.08 95% CI: 0.88-1.32, p = 0.46). The median OS in the PSM cohort receiving no adjuvant therapy vs adjuvant therapy was 37.0 months (95% CI: 32.9-41.8) vs 45.7 months (95% CI: 38.8-56.2, HR 0.79 95% CI: 0.64-0.97, p = 0.022). Recurrence-free survival did not differ in the neoadjuvant evaluation but differed in the adjuvant evaluation - HR 1.04 (95% CI: 0.87-1.25, p = 0.66) and 0.83 (95% CI: 0.70-0.98, p = 0.03), respectively. Multivariable Cox-proportional hazard modelling in the crude cohorts showed hazard ratio 1.08 (95% CI: 0.92-1.26, p = 0.37) for administering neoadjuvant therapy and 0.86 (95% CI: 0.72-1.03, p = 0.095) for administering adjuvant therapy.

INTERPRETATION

Neoadjuvant therapy did not confer a benefit to patients undergoing CRS+HIPEC for CRCPM, whereas adjuvant therapy was associated with a benefit in this retrospective setting.

FUNDING

None.

Long-term outcomes of elderly patients with peritoneal metastases of colorectal origin after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

INTRODUCTION

Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) were reportedly safe for the elderly. However, long-term survival data in this subgroup of patients are scarce. Our aim was to evaluate the peri-operative and long-term outcomes of CRS + HIPEC in colorectal peritoneal metastases (CRC-PM) in patients ≥70 years of age.

MATERIAL AND METHODS

We retrospectively analyzed our combined institutional databases for patients who underwent CRS + HIPEC for CRC-PM. Clinical and pathological characteristics, as well as overall survival (OS) and progression-free survival (PFS) were compared between the groups. Tumor extent was measured by the peritoneal carcinomatosis index (PCI) and completeness of cytoreduction by the CCR score. Major morbidity was defined according to Clavien-Dindo classification.

RESULTS

The dataset of 159 patients included 33 elderly and 126 non-elderly patients. Clinical characteristics between the groups differed only in medical comorbidities (Charlson comorbidity index 10 vs. 7, P < 0.001) and delivery of post-HIPEC adjuvant treatment (12.5% vs. 43.8%, P = 0.004). Overall PCI and CCR0 rates were similar between the groups, as were length of stay and major morbidity and mortality rates. Long-term outcomes in the elderly group were lower than those of the non-elderly (median OS: 21.8 vs. 40.5 months, P < 0.001; median PFS: 6 vs. 8 months, P = 0.02, respectively).

CONCLUSIONS

CRS + HIPEC in selected elderly patients can be safe in terms of postoperative morbidity and mortality. However, despite the same surgical extents and radicality, their long-term outcomes are inferior, possibly due to under-usage of systemic chemotherapy.

The Impact of Neoadjuvant Chemotherapy on the Surgical Management of Colorectal Peritoneal Metastases: A Systematic Review and Meta-Analysis

Background

Cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) is a well-recognised treatment option for the management of colorectal peritoneal metastases (CRPM). However, incorporating the routine use of neoadjuvant chemotherapy (NAC) into this management plan is controversial.

Methods

A systematic review and meta-analysis were conducted to evaluate the impact of neoadjuvant chemotherapy on perioperative morbidity and mortality, and long-term survival of patients with CRPM undergoing CRS and HIPEC.

Results

Twelve studies met the inclusion criteria (n = 2,463 patients). Ten were retrospective cohort, one was prospective cohort, and one was a prospective randomised by design. Patients who received NAC followed by CRS and HIPEC experienced no difference in major perioperative morbidity and mortality compared with patients who underwent surgery first (SF). There was no difference in overall survival at 3 years, but at 5 years NAC patients had superior survival (relative risk [RR] 1.31; 95% confidence interval [CI] 1.11–1.54, P < 0.001). There were no differences in 1- and 3-year, disease-free survival (DFS) between groups. Study heterogeneity was generally high across all outcome measures.

Conclusions

Patients who received neoadjuvant chemotherapy did not experience any increase in perioperative morbidity or mortality. The potential improvement in 5-year overall survival in patients receiving NAC is based on limited confidence due to several limitations in the data, but not sufficiently enough to curtail its use. The practice of NAC in this setting will remain heterogeneous and guided by retrospective evidence until prospective, randomised data are reported.

Peritoneal Metastasis: Current Status and Treatment Options

Simple Summary

Surgical and locoregional treatments of peritoneal metastasis, e.g., from colorectal cancer, has gained increasing acceptance after the publication of excellent patient outcomes from many groups around the world. Apart from systemic chemotherapy and surgical removal of the tumor, locoregional therapies such as HIPEC or PIPAC may improve tumor control. Understanding the molecular characteristics of peritoneal metastasis is crucial to evolve future therapeutic strategies for peritoneal metastasis. This includes the genetic background of PM, which is often different from other sites of metastasis, and promotes peritoneal dissemination and the growth of tumor cells. Growing knowledge and insight into the physiology of the peritoneal tumor microenvironment and the specific role of the immune system in this compartment may provide a critical step to move locoregional therapy to the next level. This review summarizes the current knowledge and highlights the molecular characteristics of peritoneal metastasis.

Abstract

Peritoneal metastasis (PM) originating from gastrointestinal cancer was considered a terminal disease until recently. The advent of better systemic treatment, a better understanding of prognostic factors, and finally, the advent of novel loco-regional therapies, has opened the door for the multimodal treatment of PM. These strategies, including radical surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) showed surprisingly good results, leading to the prolonged survival of patients with peritoneal metastasis. This has triggered a significant body of research, leading to the molecular characterization of PM, which may further help in the development of novel treatments. This review summarizes current evidence on peritoneal metastasis and explores potential novel mechanisms and therapeutic approaches to treat patients with peritoneal metastasis.

Risk factors for developing peritoneal metastases after curative surgery for colorectal cancer: A systematic review and meta-analysis

AIM

Proactive detection and treatment strategies have achieved encouraging survival outcomes for patients with early peritoneal metastases (PM), but these costly and invasive approaches can only be applied to selected high-risk patients. This meta-analysis aimed to identify the risk factors for metachronous PM after curative surgery for colorectal cancer (CRC).

METHOD

The study was registered at PROSPERO (CRD42020219187). Databases were searched for studies comparing clinical and histopathological characteristics between patients with metachronous peritoneal metastases from colorectal cancer (pmCRC) and patients without (non-pmCRC).

RESULTS

Thirty-six studies were included. Metachronous PM were positively associated with perforation (OR 1.920; 95% CI 1.144-3.223; P = 0.014), poor differentiation (OR 2.291; 1.603-3.275; P < 0.001), T4 (OR 2.897; 1.248-6.726; P = 0.013), N1-2 (OR 3.429; 2.684-4.381; P < 0.001), mucinous adenocarcinoma (OR 4.175; 1.798-9.692; P = 0.001), obstruction (OR 4.467; 1.919-10.398; P = 0.001), synchronous ovarian metastases (OR 5.005; 1.140-21.977; P = 0.033), positive peritoneal carcinoembryonic antigen mRNA (OR 9.472; 3.643-24.631; P < 0.001), elevated serum carcinoembryonic antigen (preoperative group, OR 3.545, 1.486-8.459, P = 0.004; postoperative group, OR 13.673, 2.222-84.129, P = 0.005), elevated serum cancer antigen 19-9 (preoperative group, OR 5.281, 2.146-12.994, P < 0.001; postoperative group, OR 18.646, 6.429-54.083, P < 0.001) and positive peritoneal cytology (OR 25.884; 11.372-58.913; P < 0.001).

CONCLUSION

These evidence-based risk factors are conducive to designing early detection and proactive treatment strategies, enabling precision medicine.

Quality Standards for Surgery of Colorectal Peritoneal Metastasis After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

The standardization of surgical outcomes throughout surgical procedures is mandatory. Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) should provide proficient oncological and surgical outcomes.

STUDY DESIGN

The aim of this study was to identify clinically relevant quality indicators and their quality standard, and to determine their acceptable quality limit. A systematic review on cytoreductive results from 2000 to 2018 was performed focusing on clinical guidelines, consensus conferences, and publications. After the selection of quality indicators, a systematic review of indexed references was performed in order to calculate the quality standard for each indicator.

STUDY SELECTION

Unicentric/multicentric series, comparative studies, and clinical trials. Studies were to include outcomes after cytoreduction of colorectal origin and series with more than 50 patients. Quality indicators with at least 10 series were mandatory and objective measurements were also mandatory for inclusion.

MAIN OUTCOME MEASUREMENTS

Quality indicators selected were 1- to 5-year survival, overall disease-free survival, 1- to 5-year disease-free survival, complete surgical resection, duration of surgery, length of stay, overall morbimortality, major morbidity, re-intervention, postoperative hemorrhage, intestinal fistula, anastomotic leakage, wound infection, postoperative medical complications, overall recurrence, and failure to rescue.

RESULTS

The most relevant quality indicators and critical quality limits were overall disease-free survival and 5-year overall disease-free survival (14 months and <10 months, and 14% and <4%, respectively), completeness of surgical resection (89% and <80%, respectively), overall mortality (3% and >8%, respectively), overall morbidity (47% and >63%, respectively), failure to rescue (12% and <30%, respectively), reintervention (13 and <22%, respectively), anastomotic leakage (6% and <13%, respectively), and overall recurrence (60% and <74%, respectively).

CONCLUSION

This is the first study to assess quality standards in CRS + HIPEC for colorectal peritoneal metastases. The current data are of particular relevance for future studies to control the variability of this surgery.

Direct surgery with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for patients with colorectal peritoneal metastases

INTRODUCTION

Neoadjuvant chemotherapy is widely used in treatment of peritoneal metastases from colorectal cancer, but there is little scientific evidence for this approach. This study aimed to study survival in patients treated with direct surgery with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), i.e. without neoadjuvant chemotherapy.

MATERIAL AND METHODS

Patients with histopathologically confirmed peritoneal metastases from colorectal cancer that underwent first-time CRS-HIPEC with complete cytoreduction (CC0 or 1) at Karolinska University Hospital 2012-2019 were included. Patients with synchronous extraperitoneal metastases were excluded if not treated before end of follow-up. Factors associated with overall survival (OS) and disease-free survival (DFS) were evaluated using the Kaplan-Meier method and Cox regression models. The multivariable models were adjusted for sex, age, synchronous/metachronous peritoneal metastases, peritoneal carcinomatosis index (PCI), extraperitoneal metastases and the pathological tumor (T) and lymph node (N) stage of the primary tumor.

RESULTS

In all, 131 patients underwent complete CRS-HIPEC for peritoneal metastases without neoadjuvant chemotherapy. The median OS and DFS were 40.3 months and 12.5 months, respectively, in patients treated with direct surgery. In the multivariable model, PCI≥16 was the only variable associated with decreased OS, whereas elevated PCI, metachronous development of peritoneal metastases and synchronous extraperitoneal metastases were associated with decreased DFS. Age was not associated with an impaired prognosis.

CONCLUSION

Patients who underwent direct surgery with CRS-HIPEC had a good prognosis, with a median OS of more than 3 years. The results from this study question the need of neoadjuvant chemotherapy in all patients eligible for CRS-HIPEC.

Perioperative Systemic Therapy vs Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Alone for Resectable Colorectal Peritoneal Metastases: A Phase 2 Randomized Clinical Trial

Importance

To date, no randomized clinical trials have investigated perioperative systemic therapy relative to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) alone for resectable colorectal peritoneal metastases (CPM).

Objective

To assess the feasibility and safety of perioperative systemic therapy in patients with resectable CPM and the response of CPM to neoadjuvant treatment.

Design, Setting, and Participants

An open-label, parallel-group phase 2 randomized clinical trial in all 9 Dutch tertiary centers for the surgical treatment of CPM enrolled participants between June 15, 2017, and January 9, 2019. Participants were patients with pathologically proven isolated resectable CPM who did not receive systemic therapy within 6 months before enrollment.

Interventions

Randomization to perioperative systemic therapy or CRS-HIPEC alone. Perioperative systemic therapy comprised either four 3-week neoadjuvant and adjuvant cycles of CAPOX (capecitabine and oxaliplatin), six 2-week neoadjuvant and adjuvant cycles of FOLFOX (fluorouracil, leucovorin, and oxaliplatin), or six 2-week neoadjuvant cycles of FOLFIRI (fluorouracil, leucovorin, and irinotecan) and either four 3-week adjuvant cycles of capecitabine or six 2-week adjuvant cycles of fluorouracil with leucovorin. Bevacizumab was added to the first 3 (CAPOX) or 4 (FOLFOX/FOLFIRI) neoadjuvant cycles.

Main Outcomes and Measures

Proportions of macroscopic complete CRS-HIPEC and Clavien-Dindo grade 3 or higher postoperative morbidity. Key secondary outcomes were centrally assessed rates of objective radiologic and major pathologic response of CPM to neoadjuvant treatment. Analyses were done modified intention-to-treat in patients starting neoadjuvant treatment (experimental arm) or undergoing upfront surgery (control arm).

Results

In 79 patients included in the analysis (43 [54%] men; mean [SD] age, 62 [10] years), experimental (n = 37) and control (n = 42) arms did not differ significantly regarding the proportions of macroscopic complete CRS-HIPEC (33 of 37 [89%] vs 36 of 42 [86%] patients; risk ratio, 1.04; 95% CI, 0.88-1.23; P = .74) and Clavien-Dindo grade 3 or higher postoperative morbidity (8 of 37 [22%] vs 14 of 42 [33%] patients; risk ratio, 0.65; 95% CI, 0.31-1.37; P = .25). No treatment-related deaths occurred. Objective radiologic and major pathologic response rates of CPM to neoadjuvant treatment were 28% (9 of 32 evaluable patients) and 38% (13 of 34 evaluable patients), respectively.

Conclusions and Relevance

In this randomized phase 2 trial in patients diagnosed with resectable CPM, perioperative systemic therapy seemed feasible, safe, and able to induce response of CPM, justifying a phase 3 trial.

Trial Registration

ClinicalTrials.gov Identifier: NCT02758951.

Neoadjuvant chemotherapy followed by hyperthermic intraperitoneal chemotherapy for patients with colorectal peritoneal metastasis: a retrospective study of its safety and efficacy

Background

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are effective routine treatments for colorectal peritoneal metastasis (PM). However, the safety and efficacy of neoadjuvant chemotherapy (NAC) before CRS+HIPEC are poorly understood. Therefore, this study aimed to assess the perioperative safety and long-term efficacy of NAC prior to CRS+HIPEC for patients with synchronous colorectal PM.

Methods

Patients with synchronous colorectal PM who received NAC prior to CRS+HIPEC were systematically reviewed at the China National Cancer Center and Huanxing Cancer Hospital from June 2017 to June 2019. The clinicopathologic characteristics, perioperative parameters, and survival rates of patients who underwent CRS+HIPEC with NAC (NAC group) and patients who underwent CRS+HIPEC without NAC (non-NAC group) were compared.

Results

The study enrolled 52 patients, with 20 patients in the NAC group and 32 in the non-NAC group. In the NAC group, the proportion of patients with a peritoneal carcinomatosis index (PCI) score < 12 was significantly higher than that in the non-NAC group (80.0% vs 50.0%, P = 0.031), and more patients achieved complete cytoreduction (80.0% vs 46.9%, P = 0.018). The two groups had comparable grade III/IV complications and similar reoperation and mortality rates (P > 0.05). However, patients who received NAC had lower platelet counts (151.9 vs 197.7 × 10⁹/L, P = 0.036) and neutrophil counts (4.7 vs 7.2 × 10⁹/L, P = 0.030) on postoperative day 1. More patients survived for 2 years in the NAC group than in the non-NAC group (67.4% vs 32.2%, respectively, P = 0.044). However, the completeness of cytoreduction score (HR, 2.99; 95% CI, 1.14–7.84; P = 0.026), rather than NAC, was independently associated with overall survival (OS) in the multivariate analysis after controlling for confounding factors.

Conclusion

NAC administration before CRS+HIPEC can be regarded as safe and feasible for patients with colorectal PM with comparably low mortality rates and acceptable morbidity rates. Nevertheless, large-sample randomized controlled studies are needed to confirm whether the administration of NAC before CRS+HIPEC confers a survival benefit to patients.

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.

The absence of benefit of perioperative chemotherapy in initially resectable peritoneal metastases of colorectal cancer origin treated with complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: A retrospective analysis

INTRODUCTION

The aim of this study was to compare the outcome of patients with peritoneal metastasis (PM) of colorectal origin treated with complete cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) with or without perioperative systemic chemotherapy (PCT+/PCT-).

PATIENTS AND METHODS

Retrospective analysis of 125 patients treated with complete CRS (R0/R1) and HIPEC for PM from colorectal origin in two Belgian academic centers between 2008 and 2017. Disease-free survival (DFS) and overall survival (OS) were assessed with regard to PCT. Statistical analyses were adjusted for non-balanced survival risk factors.

RESULTS

The PCT+ group (n = 67) received at least 5 cycles of PCT and the PCT-group (n = 56) did not receive PCT. The groups were well balanced for all prognostic factors except presentation of synchronous disease (more in PCT+). Survival analysis was adjusted to peritoneal cancer index and presentation of synchronous disease. After a median follow-up of 54±5-months, the 1, 3, 5-years OS in the PCT+ group were 98%, 59% and 35% compared to 97%, 77% and 56% in the PCT-group (HR = 1.46; 95% CI:0.87-2.47; p = 0.155). The 1,3 and 5 years DFS in the PCT+ group were 47%, 13% and 6% compared to 58%, 29% and 26% respectively in the PCT- (HR = 1.22; 95% CI:0.78-1.92; p = 0.376).

CONCLUSION

This study does not show any clear benefit of PCT in carefully selected patients undergoing R0/R1 CRS and HIPEC for colorectal PM. The ongoing CAIRO6 trial randomizing CRS/HIPEC versus CRS/HIPEC and PCT will probably clarify the role of PCT in patients with resectable PM.

Prognostic factors influencing survival in patients undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for isolated colorectal peritoneal metastases: a systematic review and meta-analysis

AIM

Peritoneal metastases from colorectal cancer confer the worst survival among all metastatic sites. The adoption of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) can offer selected patients with isolated colorectal peritoneal metastases (CRPM) a favourable long-term survival. There are numerous factors postulated to influence survival in patients undergoing CRS and HIPEC. The aim of this study was to identify the key perioperative prognostic factors that influence survival in patients undergoing CRS and HIPEC for isolated CRPM.

METHOD

A systematic review and meta-analysis were conducted to evaluate prognostic factors influencing survival in patients undergoing CRS and HIPEC for isolated CRPM.

RESULTS

Thirty-three studies fitted the inclusion criteria for the systematic review, with 25 studies included in the meta-analysis. On pooled analysis, incomplete cytoreduction, increasing peritoneal carcinoma index (PCI) and lymph node involvement were significantly associated with a worse survival. Additionally, a rectal primary [hazard ratio (HR) 1.93, 95% CI 1.10-3.37], adjuvant chemotherapy (HR 0.71, 95% CI 0.54-0.93) and perioperative grade III/IV morbidity (HR 1.59, 95% CI 1.17-2.16) were also found to significantly influence survival. Notably, tumour differentiation and signet ring cell histology did not influence survival on pooled analysis.

CONCLUSION

This meta-analysis confirms that in patients undergoing CRS and HIPEC for isolated CRPM, incomplete cytoreduction, high PCI and lymph node involvement have a negative influence on survival. In addition, a rectal primary, adjuvant chemotherapy use and grade III/IV morbidity are important factors that also significantly influence survival.

Diagnostic and therapeutic algorithm for colorectal peritoneal metastases. A consensus of the peritoneal surface malignancies onco-team of the Italian society of surgical oncology

AIM

the surgical workup for colorectal cancer peritoneal metastases (CRCPM) is complex and should be managed in specialized centers. Diagnostic and therapeutic algorithms (DTA) have been proposed to balance optimal patients management and correct use of resources. Aim of this study was to establish a consensus on DTA for CRCPM patients in Italy.

METHOD

a panel of 18 delegated members of centers afferent to Peritoneal Surface Malignancies Onco-team of the Italian Society of Surgical Oncology was established. A list of statements regarding the DTA of patients with CRCPM was prepared according to different activities and decision-making nodes with a defined entry and exit point. Consensus was obtained through RAND UCLA methodology.

RESULTS

two different DTA were defined and approved according to the modality of presentation of CRCPM (synchronous and metachronous). A consensus was also obtained on 17 of the 19 statements related to DTA.

CONCLUSION

a shared model of DTA is now available for healthcare providers to monitor appropriateness in diagnosis and treatment of patients with isolated peritoneal metastases from CRC.

Expanding Uses of HIPEC for Locally Advanced Colorectal Cancer: A European Perspective

Locally advanced colorectal cancer is a challenge for surgeons and medical oncologist; 10 to 20% colorectal cancer debut as locally advanced disease, with tumors extending through the colon wall with perforation and/or invasion of adjacent organs or structures. Those locally advanced tumors have a worse prognostic at any stage due not only to systemic dissemination but also in a high percentage of patients, to locoregional recurrence, in fact, peritoneal carcinomatosis of colorectal origin is so predictable that we can assess the risk for each patient according to some histopathological and clinical features: small peritoneal nodules resected in the first surgery (70% probability), ovarian metastases (60%), perforated tumor onset or intraoperative tumor rupture (50%), positive cytology (40%), and pT4/mucinous pT3 up to 40%. Prophylactic or adjuvant hyperthermic intraperitoneal chemotherapy seems to be a promising strategy for patients with advanced colorectal cancer to prevent the development of peritoneal recurrence and improve prognosis of this group of patients.

Taiwan Society of Colon and Rectal Surgeons (TSCRS) Consensus for Cytoreduction Selection in Metastatic Colorectal Cancer

BACKGROUND

Taiwan has witnessed a surge in the incidence of colorectal cancer (CRC), of which 40-60% metastasize. Continuous updating of cytoreductive strategies in metastatic CRC (mCRC) has contributed to median overall survival reaching 40 months. In this changing scenario, to standardize the approaches across Taiwan, a group of experts from the Taiwan Society of Colon and Rectal Surgeons (TSCRS) convened to establish evidence- and opinion-based recommendations for defining the criteria of "resectability" in mCRC.

METHODS

Over the course of one-on-one consultations, lasting 30-40 min each, with 30 medical specialists (19 colorectal surgeons, 4 general surgeons, and 7 medical oncologists) from 16 hospitals in Taiwan followed by a 2-h meeting with 8 physician experts (3 general surgeons, 4 colorectal surgeons, and 1 thoracic surgeon), 12 key questions on cytoreduction were addressed. This was further contextualized based on published literature.

RESULTS

The final consensus includes eight recommendations regarding the criteria for metastasis resection, role of local control treatment in liver potentially resectable patients, management of synchronous liver metastases, approach for peritoneal metastasis, place for resection in multiple-organ metastasis, and general criteria for resectability.

CONCLUSIONS

mCRC patients undergoing R0 resection have the greatest survival advantage following surgery. Our role as a multidisciplinary team (MDT) should be to treat potentially resectable mCRC patients as rapidly and safely as possible, and achieve R0 resection as far as possible and for as long as possible (continuum of care). This TSCRS consensus statement aims to help build clinical capacity within the MDTs, while making better use of existing healthcare resources.

Adjuvant Systemic Chemotherapy vs Active Surveillance Following Up-front Resection of Isolated Synchronous Colorectal Peritoneal Metastases

Importance

To date, there are no data on the value of adjuvant systemic chemotherapy following up-front resection of isolated synchronous colorectal peritoneal metastases.

Objective

To assess the association between adjuvant systemic chemotherapy and overall survival following up-front resection of isolated synchronous colorectal peritoneal metastases.

Design, Setting, and Participants

In this population-based, observational cohort study using nationwide data from the Netherlands Cancer Registry (diagnoses between January 1, 2005, and December 31, 2017; follow-up until January 31, 2019), 393 patients with isolated synchronous colorectal peritoneal metastases who were alive 3 months after up-front complete cytoreductive surgery with hyperthermic intraperitoneal chemotherapy were included. Patients allocated to the adjuvant systemic chemotherapy group were matched (1:1) with those allocated to the active surveillance group by propensity scores based on patient-, tumor-, and treatment-level covariates.

Exposures

Adjuvant systemic chemotherapy, defined as systemic chemotherapy without targeted therapy, starting within 3 months postoperatively.

Main Outcomes and Measures

Overall survival was compared between matched groups using Cox proportional hazards regression analysis adjusted for residual imbalance. A landmark analysis was performed by excluding patients who died within 6 months postoperatively. A sensitivity analysis was performed to adjust for unmeasured confounding by major postoperative morbidity.

Results

Of 393 patients (mean [SD] age, 61 [10] years; 181 [46%] men), 172 patients (44%) were allocated to the adjuvant systemic chemotherapy group. After propensity score matching of 142 patients in the adjuvant systemic chemotherapy group with 142 patients in the active surveillance group, adjuvant systemic chemotherapy was associated with improved overall survival compared with active surveillance (median, 39.2 [interquartile range, 21.1-111.1] months vs 24.8 [interquartile range, 15.0-58.4] months; adjusted hazard ratio [aHR], 0.66; 95% CI, 0.49-0.88; P = .006), which remained consistent after excluding patients who died within 6 months postoperatively (aHR, 0.68; 95% CI, 0.50-0.93; P = .02) and after adjustment for major postoperative morbidity (aHR, 0.71; 95% CI, 0.53-0.95).

Conclusions and Relevance

Findings of this study suggest that in patients undergoing up-front resection of isolated synchronous colorectal peritoneal metastases, adjuvant systemic chemotherapy appeared to be associated with improved overall survival. Although randomized trials are needed to address the influence of potential residual confounding and allocation bias on this association, results of this study may be used for clinical decision-making in this patient group for whom no data are available.

[Treatment of primary and metastatic peritoneal tumors in the Covid-19 pandemic. Proposals for prioritization from the RENAPE and BIG-RENAPE groups]

La pandémie de COVID-19 modifie profondément l’organisation et l’accès aux soins, en particulier pour les pathologies néoplasiques péritonéales, dont la prise en charge curative mobilise des moyens importants en personnel, bloc opératoire et réanimation. Les groupes BIG-RENAPE et RENAPE proposent des pistes de réflexion et de priorisation pour leur prise en charge. Un renforcement des critères habituels de sélection est nécessaire pour une prise en charge à visée curative : patients jeunes, avec peu de co-morbidités et une extension péritonéale limitée. Il est souhaitable de prioriser les pathologies pour lesquelles la chirurgie de cytoréduction associée ou non à une chimiohyperthermie intrapéritonéale (CHIP) est le traitement de référence et celles pour lesquelles la chimiothérapie systémique ne peut être une alternative temporaire ou prolongée : pseudomyxomes péritonéaux ; mésothéliomes péritonéaux malins résécables ; métastases péritonéales d’origine colorectale si résécables, non répondeuses à la chimiothérapie systémique et/ou après 12 cures, carcinoses ovariennes en 1^re intention si résécables et limitées ou en situation intervallaire après un maximum de 6 cycles de chimiothérapie systémique. L’adjonction d’une CHIP devra être discutée au cas par cas, en centre expert. La priorisation des indications devra prendre en considération les conditions locales et la phase de la période épidémique pour permettre une prise en charge péri-opératoire optimale.

Treatment of primary and metastatic peritoneal tumors in the Covid-19 pandemic. Proposals for prioritization from the RENAPE and BIG-RENAPE groups

The Covid-19 pandemic is profoundly changing the organization of healthcare access. This is particularly so for peritoneal neoplastic diseases, for which curative treatment mobilizes substantial personnel, operating room and intensive care resources. The BIG-RENAPE and RENAPE groups have made tentative proposals for prioritizing care provision. A tightening of the usual selection criteria is needed for curative care: young patients with few or no comorbidities and limited peritoneal extension. It is desirable to prioritize disease conditions for which cytoreduction surgery with or without associated hyperthermic intraoperative peritoneal chemotherapy (HIPEC) is the gold-standard treatment, and for which systemic chemotherapy cannot be a temporary or long-term alternative: pseudomyxoma peritonei, resectable malignant peritoneal mesotheliomas, peritoneal metastases of colorectal origin if they are resectable and unresponsive to systemic chemotherapy after up to 12 courses, first-line ovarian carcinomatosis if resectable or in interval surgery after at most six courses of systemic chemotherapy. Addition of HIPEC must be discussed case by case in an expert center. The prioritization of indications must consider local conditions and the phase of the epidemic to allow optimal peri-operative care.

Optimal perfusion chemotherapy: A prospective comparison of mitomycin C and oxaliplatin for hyperthermic intraperitoneal chemotherapy in metastatic colon cancer

BACKGROUND

Peritoneal carcinomatosis of colorectal adenocarcinoma (CRC) origin is common and is the second-most frequent cause of death in colorectal cancer. There is survival benefit to surgical resection plus hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with metastatic CRC. However, there remains controversy between oxaliplatin (Oxali) and mitomycin C (MMC), as the agent of choice.

METHODS

A review of our 285 patients prospective HIPEC database from July 2007 to May 2018 identified 48 patients who underwent cytoreductive surgery plus HIPEC with MMC or Oxali. Patients were stratified based on preoperative and postoperative peritoneal cancer indices (PCI). The primary outcomes of survival and progression-free survival were compared.

RESULTS

Type of HIPEC chemotherapy was not found to be predictive of overall survival. Preoperative PCI (P = .04), preoperative response to chemotherapy (P = .0001), and postoperative PCI (P = .05) were predictive for overall survival.

CONCLUSIONS

MMC or Oxali based HIPEC chemotherapy are both safe and effective for the management of peritoneal only metastatic CRC. Both perfusion therapies should be considered with all patients receiving modern induction chemotherapy.

Colorectal cancer peritoneal metastases: Biology, treatment and next steps

The presence of peritoneal metastases in patients with advanced colorectal cancer is associated with poor prognosis but the mechanisms for this are unclear. This review summarises the current knowledge of the pathophysiology, clinical features, prevalence, prognosis, and molecular biology of peritoneal metastases and the risk factors for the development of peritoneal metastases following resection of a primary colorectal tumour. Furthermore, the evidence for treatment strategies are described including cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, early post-operative intraperitoneal chemotherapy, sequential post-operative intraperitoneal chemotherapy and emerging novel strategies. Active areas of research should include the identification of individuals at high risk of peritoneal metastases after curative resection of primary tumour, development of a surveillance program for high-risk patients, optimisation of systematic therapies and further investigation of the use of intraperitoneal chemotherapy.

Impact of Neoadjuvant Chemotherapy on the Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: A Multi-Institutional Retrospective Review

Cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with improved survival for patients with colorectal peritoneal metastases (CR-PM). However, the role of neoadjuvant chemotherapy (NAC) prior to CRS-HIPEC is poorly understood. A retrospective review of adult patients with CR-PM who underwent CRS+/-HIPEC from 2000–2017 was performed. Among 298 patients who underwent CRS+/-HIPEC, 196 (65.8%) received NAC while 102 (34.2%) underwent surgery first (SF). Patients who received NAC had lower peritoneal cancer index score (12.1 + 7.9 vs. 14.3 + 8.5, p = 0.034). There was no significant difference in grade III/IV complications (22.4% vs. 16.7%, p = 0.650), readmission (32.3% vs. 23.5%, p = 0.114), or 30-day mortality (1.5% vs. 2.9%, p = 0.411) between groups. NAC patients experienced longer overall survival (OS) (median 32.7 vs. 22.0 months, p = 0.044) but similar recurrence-free survival (RFS) (median 13.8 vs. 13.0 months, p = 0.456). After controlling for confounding factors, NAC was not independently associated with improved OS (OR 0.80) or RFS (OR 1.04). Among patients who underwent CRS+/-HIPEC for CR-PM, the use of NAC was associated with improved OS that did not persist on multivariable analysis. However, NAC prior to CRS+/-HIPEC was a safe and feasible strategy for CR-PM, which may aid in the appropriate selection of patients for aggressive cytoreductive surgery.

Prophylactic HIPEC in pT4 Colon Tumors: Proactive Approach or Overtreatment?

Background

The peritoneum is the second most common site for metastasis in patients with colorectal cancer. Various factors have been studied to identify patients at risk of developing peritoneal carcinomatosis (PC), including T4 tumors. The objectives were to assess the incidence of synchronous and metachronous PC, explore potential risk factors for developing PC as the only site of metastasis, and identify which patients might be candidates for prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC).

Methods

We conducted a retrospective analysis of 125 patients with pT4 colon cancer who underwent surgery in a single center between January 2010 and December 2014.

Results

Of the 947 colon cancer patients who underwent surgery, 125 (13.2%) were diagnosed with pT4a or b colon carcinoma. The median follow-up was 3.7 years. The overall rate of PC was 34.3%, being synchronous in 12% and metachronous in 22.3% of cases. The 8% and 6% of synchronous and metachronous cases of PC respectively were isolated (single site) metastasis. The incidence of PC was 6.1% at 1 year and 14.5% at 3 years after surgery. pT4 was not found to be an independent risk factor for the development of PC (p = 0.231). Nonetheless, the rate of metachronous PC as a single site of metastasis was higher in patients with pT4 tumors and peritoneal nodules around the primary tumor and/or tumor perforation (p = 0.027) and/or who underwent emergency surgery (p = 0.043) than other patients.

Conclusions

Considering pT4 tumor stage as the only risk factor for the development of PC in deciding whether to administer prophylactic HIPEC would lead to unjustified overtreatment.

Perioperative systemic therapy and cytoreductive surgery with HIPEC versus upfront cytoreductive surgery with HIPEC alone for isolated resectable colorectal peritoneal metastases: protocol of a multicentre, open-label, parallel-group, phase II-III, randomised, superiority study (CAIRO6)

Background

Upfront cytoreductive surgery with HIPEC (CRS-HIPEC) is the standard treatment for isolated resectable colorectal peritoneal metastases (PM) in the Netherlands. This study investigates whether addition of perioperative systemic therapy to CRS-HIPEC improves oncological outcomes.

Methods

This open-label, parallel-group, phase II-III, randomised, superiority study is performed in nine Dutch tertiary referral centres. Eligible patients are adults who have a good performance status, histologically or cytologically proven resectable PM of a colorectal adenocarcinoma, no systemic colorectal metastases, no systemic therapy for colorectal cancer within six months prior to enrolment, and no previous CRS-HIPEC. Eligible patients are randomised (1:1) to perioperative systemic therapy and CRS-HIPEC (experimental arm) or upfront CRS-HIPEC alone (control arm) by using central randomisation software with minimisation stratified by a peritoneal cancer index of 0–10 or 11–20, metachronous or synchronous PM, previous systemic therapy for colorectal cancer, and HIPEC with oxaliplatin or mitomycin C. At the treating physician’s discretion, perioperative systemic therapy consists of either four 3-weekly neoadjuvant and adjuvant cycles of capecitabine with oxaliplatin (CAPOX), six 2-weekly neoadjuvant and adjuvant cycles of 5-fluorouracil/leucovorin with oxaliplatin (FOLFOX), or six 2-weekly neoadjuvant cycles of 5-fluorouracil/leucovorin with irinotecan (FOLFIRI) followed by four 3-weekly (capecitabine) or six 2-weekly (5-fluorouracil/leucovorin) adjuvant cycles of fluoropyrimidine monotherapy. Bevacizumab is added to the first three (CAPOX) or four (FOLFOX/FOLFIRI) neoadjuvant cycles. The first 80 patients are enrolled in a phase II study to explore the feasibility of accrual and the feasibility, safety, and tolerance of perioperative systemic therapy. If predefined criteria of feasibility and safety are met, the study continues as a phase III study with 3-year overall survival as primary endpoint. A total of 358 patients is needed to detect the hypothesised 15% increase in 3-year overall survival (control arm 50%; experimental arm 65%). Secondary endpoints are surgical characteristics, major postoperative morbidity, progression-free survival, disease-free survival, health-related quality of life, costs, major systemic therapy related toxicity, and objective radiological and histopathological response rates.

Discussion

This is the first randomised study that prospectively compares oncological outcomes of perioperative systemic therapy and CRS-HIPEC with upfront CRS-HIPEC alone for isolated resectable colorectal PM.

Trial registration

Clinicaltrials.gov/NCT02758951, NTR/NTR6301, ISRCTN/ISRCTN15977568, EudraCT/2016–001865-99.

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.

Neoadjuvant chemotherapy followed by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for colorectal cancer: a feasibility and safety study

BACKGROUND

Standard treatment for colorectal peritoneal carcinomatosis typically involves cytoreductive surgery, hyperthermic intraperitoneal chemotherapy (HIPEC), and if possible, postoperative adjuvant chemotherapy. However, a substantial percentage of patients never receive adjuvant chemotherapy because of postoperative complications. Neoadjuvant chemotherapy could be beneficial in this setting, so we assessed its feasibility and safety when used before cytoreductive surgery and HIPEC.

METHODS

In this non-randomized, single-center, observational feasibility study, patients were scheduled to receive six cycles of capecitabine and oxaliplatin before cytoreductive surgery and HIPEC. Computed tomography was performed after the third and sixth chemotherapy cycles to evaluate tumor response, and patients underwent cytoreductive surgery and HIPEC if there were no pulmonary and/or hepatic metastases. Postoperative complications, graded according to the Clavien-Dindo classification, were compared with those of a historic control group that received postoperative adjuvant chemotherapy.

RESULTS

Of the 14 patients included in the study, 4 and 3 had to terminate neoadjuvant chemotherapy early because of toxicity and tumor progression, respectively. Cytoreductive surgery and HIPEC were performed in eight patients, and the timing and severity of complications were comparable to those of patients in the historic control group treated without neoadjuvant chemotherapy.

CONCLUSION

Patients with peritoneal metastases due to colorectal carcinoma can be treated safely with neoadjuvant chemotherapy before definitive therapy with cytoreductive surgery and HIPEC.

TRIAL REGISTRATION NUMBER

NTR 3905, registered on 20th march, 2013, http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3905.

Perioperative Systemic Chemotherapy, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy in Patients With Colorectal Peritoneal Metastasis: Results of the Prospective Multicenter Phase 2 COMBATAC Trial

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) as parts of an interdisciplinary treatment concept including systemic chemotherapy can improve survival of selected patients with peritoneal metastatic colorectal cancer (pmCRC). Nevertheless, the sequence of the therapeutic options is still a matter of debate. Thus, the COMBATAC (COMBined Anticancer Treatment of Advanced Colorectal cancer) trial was conducted to evaluate a combined treatment regimen consisting of preoperative systemic polychemotherapy + cetuximab followed by CRS + HIPEC and postoperative systemic polychemotherapy + cetuximab.

PATIENTS AND METHODS

The COMBATAC trial is a prospective, multicenter, open-label, single-arm, single-stage phase 2 trial. Twenty-six patients with synchronous or metachronous colorectal or appendiceal peritoneal carcinomatosis were included. Enrollment was terminated prematurely by the sponsor because of slow recruitment. Progression-free survival as primary end point and overall survival were estimated by the Kaplan-Meier method. Also evaluated were morbidity according to Common Terminology Criteria for Adverse Events v4.0 and feasibility of the combined treatment concept.

RESULTS

Median progression-free survival for the intention-to-treat population (n = 25) was 14.9 months. Median overall survival was not reached during the study duration. Ninety-two adverse events were documented in 16 patients, including 14 serious adverse events in 9 patients. The overall morbidity rate was 64%, and the grade 3/4 morbidity rate was 44%. Of all grade 3/4 morbidity events, 36.4% were related to systemic chemotherapy and 22.7% to surgery, whereas 40.9% were not directly related. There was no treatment-related mortality.

CONCLUSION

The results of the COMBATAC trial show that the multimodal treatment concept consisting of perioperative systemic chemotherapy and CRS + HIPEC is safe and feasible. Progression-free survival in selected patients with colorectal or appendiceal peritoneal metastasis might be improved.

Metachronous Peritoneal Metastases After Adjuvant Chemotherapy are Associated with Poor Outcome After Cytoreduction and HIPEC

INTRODUCTION

Cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) improve the survival of colorectal cancer (CRC) patients with peritoneal metastases. Patient selection is key since this treatment is associated with high morbidity. Patients with peritoneal recurrence within 1 year after previous adjuvant chemotherapy are thought to benefit less from HIPEC treatment; however, no published data are available to assist in clinical decision making. This study assessed whether peritoneal recurrence within 1 year after adjuvant chemotherapy was associated with survival after HIPEC treatment.

METHODS

Peritoneal recurrence within 1 year after adjuvant chemotherapy, as well as other potentially prognostic clinical and pathological variables, were tested in univariate and multivariate analysis for correlation with primary outcomes, i.e. overall survival (OS) and disease-free survival (DFS). Two prospectively collected databases from the VU University Medical Center Amsterdam and Catherina Hospital Eindhoven containing 345 CRC patients treated with the intent of HIPEC were utilized.

RESULTS

High Peritoneal Cancer Index (PCI) scores were associated with worse DFS [hazard ratio (HR) 1.04, 95% confidence interval (CI) 1.00-1.08, p = 0.040] and OS (HR 1.11, 95% CI 1.07-1.15, p < 0.001) in multivariate analysis. Furthermore, patients with peritoneal recurrence within 1 year following adjuvant chemotherapy had worse DFS (HR 2.13, 95% CI 1.26-3.61, p = 0.005) and OS (HR 2.76, 95% CI 1.45-5.27, p = 0.002) than patients who did not receive adjuvant chemotherapy or patients with peritoneal recurrence after 1 year.

CONCLUSION

Peritoneal recurrence within 1 year after previous adjuvant chemotherapy, as well as high PCI scores, are associated with poor survival after cytoreduction and HIPEC. These factors should be considered in order to avoid high-morbidity treatment in patients who might not benefit from such treatment.

Patient selection for cytoreductive surgery and HIPEC for the treatment of peritoneal metastases from colorectal cancer

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a viable option for selected patients with peritoneal metastases (PM) from colorectal origin, resulting in long-term survival and even cure in some cases. However, adequate patient selection for this treatment is currently one of the major challenges. The aim of this review is to provide a comprehensive overview of clinically relevant factors associated with overall survival. This may help to guide clinicians through the complex interplay of patient, tumor, and treatment characteristics to adequately select patients who benefit the most from this extensive surgical treatment. First, basic principles of colorectal PM and the CRS and HIPEC treatment will be discussed. According to available literature, especially extent of peritoneal disease, completeness of cytoreduction, and signet ring cell histology have great influence on the outcome after CRS and HIPEC. Other factors that seem to have a negative prognostic value are the presence of liver metastases and the absence of treatment with neo-adjuvant systemic therapy. Prognostic models combining the above-mentioned factors, such as the Colorectal Peritoneal Metastases Prognostic Surgical Score nomogram, may provide clinically relevant tools to use in everyday practice.

Clinicopathological Parameters in Patient Selection for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Cancer Metastases: A Meta-analysis

OBJECTIVE

To improve patient selection for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) by evaluating various preoperatively assessable clinicopathological parameters as markers for survival after CRS and HIPEC.

SUMMARY BACKGROUND DATA

Peritoneal metastases (PMs) originating from colorectal cancer are treated with CRS and HIPEC. Despite increasing survival, high morbidity and mortality warrant selection of patients with optimal benefit from this treatment. Many studies report a number of variables to be associated with survival after CRS and HIPEC, but no definitive analysis has been made to validate various markers.

METHODS

In concordance with PRISMA guidelines, we performed a literature search encompassing 4110 articles to select 50 articles that reported the influence of 1 or more clinicopathological variables on overall survival after CRS and HIPEC. In absence of RCTs, 25 cohort studies could be used to perform a meta-analysis on 10 prognostic variables.

RESULTS

We determined that concurrent liver metastasis, lymph node metastasis, Eastern Cooperative Oncology Group score, tumor differentiation, and signet ring cell histology are all negative prognostic variables on overall survival after CRS and HIPEC. Conversely, sex and location of primary could not be validated as prognostic markers. More research is required to make definitive conclusions about neoadjuvant chemotherapy, onset of PMs, and mucinous histology.

CONCLUSIONS

Current clinical practice, which selects patients based on extraperitoneal metastasis, lymph node stage, performance status, and tumor histology, is validated by our pooled analysis. Our data merit further research into neoadjuvant chemotherapy in the setting of CRS and HIPEC for PMs.

Timing of Systemic Chemotherapy in Patients With Colorectal Peritoneal Carcinomatosis Treated With Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Timing of systemic chemotherapy in patients with colorectal peritoneal carcinomatosis treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is controversial. Preoperative systemic chemotherapy may offer benefits.

OBJECTIVE

The purpose of this study was to evaluate the effect of timing of systemic chemotherapy on survival.

DESIGN

This was a retrospective cohort study.

SETTINGS

The study was conducted at a tertiary referral center.

PATIENTS

Patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy from January 2004 until June 2015 were included.

MAIN OUTCOME MEASURES

The influence of patient-related, tumor-related, and treatment-related factors on survival were investigated using Cox regression models. Main outcome was overall survival.

RESULTS

A total of 280 consecutive patients underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. In group A, 78 patients (28%) were treated with preoperative or perioperative chemotherapy, cytoreductive surgery, and hyperthermic intraperitoneal chemotherapy. In group B, 169 patients (60%) were intentionally treated with cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, and adjuvant chemotherapy. In group C, 33 patients (12%) had received their chemotherapy before peritoneal carcinomatosis was diagnosed. Median overall survival was 36.9 months (interquartile range, 20.6-79.7 mo) in group A, 43.1 months (interquartile range, 25.7-95.9 mo) in group B, and 34.0 months (interquartile range, 20.0-53.7 mo) in group C (p = 0.19). The extent of peritoneal carcinomatosis (region count of 3-5, HR = 1.58 (95% CI, 1.02-2.45), and 6-7, HR = 3.34 (95% CI, 1.66-6.72) vs 1-2 regions), a higher lymph node ratio (HR = 7.96 (95% CI, 2.16-29.31)), and cycles of systemic chemotherapy (0 cycles, HR = 2.52 (95% CI, 1.48-4.29)) and partial chemotherapy (HR = 2.15 (95% CI, 1.27-3.65) vs complete chemotherapy) were associated with poorer overall survival.

LIMITATIONS

Selection bias is present because of the retrospective design of this study.

CONCLUSIONS

Timing of systemic chemotherapy does not appear to have impact on survival in patients with colorectal peritoneal carcinomatosis undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy improves survival for peritoneal carcinomatosis from colorectal cancer: a systematic review and meta-analysis of current evidence

Objectives

The therapeutic efficacy of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with peritoneal carcinomatosis (PC) from colorectal cancer (CRC) is still under debate. This meta-analysis and systematic review of published literature on this comprehensive strategy aims to evaluate its efficacy on CRC patients with PC.

Methods

A systemic review with meta-analysis of published literatures on treatment of CRS plus HIPEC for patients with PC from CRC was performed. In addition, a summary of study results of published literatures concerning CRS plus HIPEC treating patients with PC from CRC was also conducted.

Results

A total of 76 studies were selected, including 1 randomized controlled trial, 14 non-randomized controlled studies, and 61 non-controlled studies. The pooled hazard ratios (HRs) for overall survival (OS) in the 15 researches for meta-analysis was 2.67 (95% CI, 2.21-3.23, I₂= 0%, P < 0.00001), and no significant evidence of publication bias was found. The difference of chemotherapy regimens of HIPEC was not associated with OS and DFS (disease-free survival) after CRS and HIPEC, with no significant difference of heterogeneity (P = 0.27, I2 = 24.1%). In both groups of mitomycin C based HIPEC group and oxaliplatin group, patients received HIPEC had significant better survival (P < 0.00001). The mean mortality and morbidity for HIPEC program were 2.8% and 33.0%, respectively.

Conclusions

This meta-analysis revealed that comprehensive therapeutic strategy of CRS plus HIPEC could bring survival benefit for selected patients with PC from CRC with acceptable safety.

Perioperative systemic therapy for resectable colorectal peritoneal metastases: Sufficient evidence for its widespread use? A critical systematic review

BACKGROUND/PURPOSE

Despite its widespread use, no randomised studies have investigated the value of perioperative systemic therapy as adjunct to cytoreduction and HIPEC for colorectal peritoneal metastases. This systematic review evaluated the available evidence, which consists of non-randomised studies only.

METHODS

A systematic search identified studies that investigated the influence of neoadjuvant, adjuvant, or perioperative systemic therapy on overall survival (OS).

RESULTS

The 11 included studies (n=1708) were clinically heterogeneous and subject to selection bias. Studies on neoadjuvant systemic therapy revealed OS benefit (n=3), no OS benefit (n=1), and superiority of chemotherapy with bevacizumab vs. chemotherapy (n=2). Studies on adjuvant systemic therapy showed no OS benefit (n=3). Studies on perioperative systemic therapy demonstrated OS benefit (n=1), and superiority of modern vs. conventional systemic therapy(n=1).

CONCLUSION

Significant limitations of available evidence question the widespread use of perioperative systemic therapy in this setting, stress the need for randomised studies, and impede conclusions regarding optimal timing and regimens. Included studies may suggest a survival benefit of neoadjuvant systemic therapy.

Second-look surgery plus hyperthermic intraperitoneal chemotherapy for patients with colorectal cancer at high risk of peritoneal carcinomatosis: Does it really save lives?

The treatment of peritoneal carcinomatosis (PC) of colorectal origin with cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) has a 5-year recurrence-free or cure rate of at least 16%, so it is no longer labeled as a fatal disease, and offers prolonged survival for patients with a low peritoneal carcinomatosis index. Metachronous PC of colorectal origin is so predictable that there is a model which has been used to successfully determine the individual risk of each patient. Patients at risk are clearly identified; those with the highest risk have small peritoneal nodules present in the first surgery (70% probability of developing PC), ovarian metastases (60%), perforated tumor onset or intraoperative tumor rupture (50%). Current clinical, biological and imaging techniques still lack sufficient sensitivity to diagnose PC in its initial stages, when CRS plus HIPEC has a greater impact and a higher cure rate. Second-look surgery with HIPEC or prophylactic HIPEC at the time of the first intervention have been proposed as means of preventing and/or anticipating clinical or radiological relapse in at-risk patients. Both techniques have shown a significant decrease in peritoneal relapses and should be considered essential weapons in the management of colorectal cancer.

The Role of Neoadjuvant and Adjuvant Systemic Chemotherapy with Cytoreductive Surgery and Heated Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: A Systematic Review

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is an effective treatment for colorectal peritoneal metastases (CPM), increasing overall survival in selected patients. The aim of this systematic review was to assess the effect of neoadjuvant and adjuvant systemic chemotherapy on overall survival in patients with CPM undergoing CRS and HIPEC, compared with those who receive CRS and HIPEC alone.

METHODS

A systematic literature review was performed using the PubMed database, and the preferred reporting items for systematic reviews and meta-analyses guidelines formed the structure of the review. Data regarding publication details, study design, patient pathology, treatments received, follow-up periods, overall survival and safety were collected and tabulated, and study quality was assessed using the MINORS score for non-randomized studies.

RESULTS

Sixteen of 288 studies met the inclusion criteria. Seven publications related to the role of neoadjuvant chemotherapy, and there was no strong evidence for the efficacy of neoadjuvant chemotherapy. Of note, one study observed worse survival outcomes when neoadjuvant therapy was used. Fourteen studies investigated the role of adjuvant chemotherapy and there was limited evidence that adjuvant systemic chemotherapy improves survival following CRS and HIPEC.

CONCLUSIONS

Systemic adjuvant chemotherapy may be associated with improved overall survival, but the role of systemic neoadjuvant chemotherapy cannot be determined by the currently available evidence. The delivery of a combination of the two modes of systemic chemotherapy has not been investigated in a randomized controlled trial to date. Further research designed to investigate the role of these modalities in the patient's treatment is required.

Hyperthermic Intraperitoneal Chemotherapy and Cytoreductive Surgery in the Management of Peritoneal Carcinomatosis

BACKGROUND

Malignant peritoneal disease can lead to significant debility due to bowel obstructions, ascites, and cancer cachexia. Moreover, inadequate imaging techniques can lead to the suboptimal detection of disease, and the poor vascularity of tumors can lead to a poor response to systemic chemotherapy. However, combination cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (HIPEC) is a promising novel treatment for patients with this disease.

METHODS

The medical literature focusing on diagnostic updates and the management of peritoneal disease was reviewed. The application principles of HIPEC for use in peritoneal disease were also summarized.

RESULTS

Improvements in imaging and the application of laparoscopic techniques have significantly increased the rate of diagnosis of early peritoneal disease with consequently less morbid cytoreductive procedures. Appropriate patient selection based on prognostic scores along with complete cytoreduction can identify a cohort of patients likely to derive durable benefit from this combination treatment.

CONCLUSIONS

Advances in diagnostic and therapeutic techniques, including surgical cytoreductive techniques, have demonstrated significant survival gains in patients with peritoneal disease. Although HIPEC can be used for the management of various types of histologies, further development of high-level evidence is necessary to advance the field.

Therapeutic options for peritoneal metastasis arising from colorectal cancer

Peritoneal metastasis is a common sign of advanced tumor stage, tumor progression or tumor recurrence in patients with colorectal cancer. Due to the improvement of systemic chemotherapy, the development of targeted therapy and the introduction of additive treatment options such as cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), the therapeutic approach to peritoneal metastatic colorectal cancer (pmCRC) has changed over recent decades, and patient survival has improved. Moreover, in contrast to palliative systemic chemotherapy or best supportive care, the inclusion of CRS and HIPEC as inherent components of a multidisciplinary treatment regimen provides a therapeutic approach with curative intent. Although CRS and HIPEC are increasingly accepted as the standard of care for selected patients and have become part of numerous national and international guidelines, the individual role, optimal timing and ideal sequence of the different systemic, local and surgical treatment options remains a matter of debate. Ongoing and future randomized controlled clinical trials may help clarify the impact of the different components, allow for further improvement of patient selection and support the standardization of oncologic treatment regimens for pmCRC. The addition of further therapeutic options such as neoadjuvant intraperitoneal chemotherapy or pressurized intraperitoneal aerosol chemotherapy, should be investigated to optimize therapeutic regimens and further improve the oncological outcome.