Results of Systematic Second-look Surgery Plus HIPEC in Asymptomatic Patients Presenting a High Risk of Developing Colorectal Peritoneal Carcinomatosis

Data-Driven Surveillance Protocol for Patients at Risk for Peritoneal Recurrence of Primary Colon Cancer: Surveillance for Peritoneal Carcinomatosis

Peritoneal carcinomatosis (PC) is rarely discovered early due to low sensitivity of screening imaging and tumor markers, however, earlier identification may improve outcomes. This study assesses risk factors and time to recurrence of PC and implementation of a surveillance system. Patients with stage II-III colon adenocarcinoma undergoing curative colectomy between 2005-2022 were retrospectively reviewed at a single tertiary care institution. Patients were divided into three cohorts: no recurrence (NR), PC, and other types of recurrence (OTR). Baseline characteristics between cohorts were compared with univariate analysis. Overall survival and PC risk were assessed using multivariate analysis with Cox's proportional-hazard modelling. 412 patients were included; 78.4% had NR, 7.8% had PC, and 13.8% had OTR. Patient demographics, comorbidities, tumor side, and histologic features were similar between cohorts. Patients with PC were more likely to have microscopic tumor perforation (25% vs. 8.8% vs. 6.8%, p = 0.002), margin involvement (25% vs. 8.8% vs. 4.6%, p < 0.001), lymphovascular invasion (56.2% vs. 33.3%, vs. 24.5%, p < 0.001), perineural invasion (28.1% vs. 15.8% vs. 11.5%, p = 0.026) compared to OTR or NR. Median time to PC after colectomy was 11 months. Tumor characteristics of stage II-III colon cancer define a high-risk profile for PC. An early surveillance program sensitive for peritoneal disease should be adopted for these patients.

Prophylactic hyperthermic intraperitoneal chemotherapy in T4 colorectal cancer: Can it improve the oncologic prognosis? - A propensity score matching study

BACKGROUND

Some studies show that cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) may improve overall survival and is a possible curative treatment for selected colorectal cancer (CRC) patients with restricted peritoneal metastasis (PM). The value of HIPEC in preventing PM of CRC is still controversial.

MATERIALS AND METHODS

In this retrospective propensity score matching (PSM) cohort study, all patients with cT4N0-2M0 undergoing treatment at a single institution in China (2014-2018) were reviewed. The 3-year disease-free survival (DFS) was set as the primary outcome, and the 3-year PM rate was also analyzed.

RESULTS

220 patients were included in this study for analysis. After 1:3 PSM: HIPEC (n = 45) and No HIPEC (n = 135). Through analysis, it was found that prophylactic HIPEC correlated to better DFS [hazard ratio (HR) 0.43, 95 % confidence interval (CI) 0.19-0.95; p = 0.037], and N2 stage correlated to worse DFS [HR 1.97, 95 % CI 1.09-3.56; p = 0.025]. For laparoscopic surgery subgroup analyses, 3-year PM rate of patients with laparoscopic surgery was 13.8 % in No HIPEC group, and 2.6 % in HIPEC group (p = 0.070). Besides, no post-operative death occurred, the anastomotic leakage rate was 2.2 % in HIPEC group and 0.7 % in the control group (p = 0.439).

CONCLUSIONS

Prophylactic HIPEC may improve the prognosis in patients with cT4N0-1M0 CRC, but not in cT4N2M0 CRC, and it does not significantly increase surgery-related complications. Laparoscopic surgery followed by HIPEC for T4 stage CRC may not increase risk of PM.

Epidemiology, oncologic results and risk stratification model for metachronous peritoneal metastases after surgery for pT4 colon cancers: results from an observational retrospective multicentre long-term follow-up study

PURPOSE

Metachronous peritoneal metastases (MPM) following a curative surgery procedure for pT4 colon cancer is a challenging condition. Current epidemiological studies on this topic are scarce.

METHODS

A retrospective multicentre trial was designed. All consecutive patients who underwent operations to treat pT4 cancers between 2015 and 2017 were reviewed. Demographic, clinical, operative, pathological and oncological follow-up variables were included. MPM were described as any oncological disease at the peritoneum, clearly different from a local recurrence. Univariate and multivariate Cox regression models were constructed. A risk stratification model was created on a cumulative factor basis. According to the calculated hazard ratio (HR), a scoring system was designed (HR < 3, 1 point; HR > 3, 2 points) and a scale from 0 to 6 was calculated for peritoneal disease-free rate (PDF-R). A risk stratification model was also created on the basis of these calculations.

RESULTS

Fifty different hospitals were involved, which included a total of 1356 patients. Incidence of MPM was 13.6% at 50 months median follow-up. The strongest independent risk factors for MPM were positive pN stage [HR 3.72 (95% CI 2.56-5.41; p < 0.01) for stage III disease], tumour perforation [HR 1.91 (95% CI 1.26-2.87; p < 0.01)], mucinous or signet ring cell histology [HR 1.68 (95% CI 1.1-2.58; p = 0.02)], poorly differentiated tumours [HR 1.54 (95% CI 1.1-2.2; p = 0.02)] and emergency surgery [HR 1.42 (95% CI 1.01-2.01; p = 0.049)]. In the absence of additional risk factors, pT4 tumours showed 98% and 96% PDF-R in 1-year and 5-year periods based on Kaplan-Meier curves.

CONCLUSIONS

Cumulative MPM incidence was 13.6% at 5-year follow-up. The sole presence of a pT4 tumour resulted in high rates of PDF-R at 1-year and 5-year follow-up (98% and 96% respectively). Five additional risk factors different from pT4 status itself were identified as possible MPM indicators during follow-up.

The Role of Prophylactic and Adjuvant Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Prevention of Peritoneal Metastases in Advanced Colorectal Cancer

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a locoregional therapy that may be combined with cytoreductive surgery (CRS) to treat patients with colorectal cancer and peritoneal metastases (PM). In recent years, three randomized controlled trials (RCTs) have investigated the role of prophylactic or adjuvant HIPEC in preventing the development of PM in patients with high-risk colorectal cancer: PROPHYLOCHIP and COLOPEC evaluated adjuvant HIPEC, and HIPECT4 studied concurrent HIPEC and CRS. Although PROPHYLOCHIP and COLOPEC were negative trials, a great deal may be learned from their methodology, outcome measures, and patient selection criteria. HIPECT4 is the first RCT to show a clinical benefit of HIPEC in high-risk T4 colorectal cancer, demonstrating improved locoregional disease control with the addition of HIPEC to CRS with no increase in the rate of complications. This review critically examines the strengths and limitations of each major trial and discusses their potential impact on the practice of HIPEC. Several additional ongoing clinical trials also seek to investigate the role of HIPEC in preventing PM in advanced colorectal cancer.

A prediction model to refine the timing of an early second-look laparoscopic exploration in patients with colon cancer at high risk of early peritoneal metastasis recurrence

BACKGROUND

In patients at high risk of peritoneal metastasis (PM) recurrence following surgical treatment of colon cancer (CC), second-look laparoscopic exploration (SLLE) is mandatory; however, the best timing is unknown. We created a tool to refine the timing of early SLLE in patients at high risk of PM recurrence.

METHODS

This international cohort study included patients who underwent CC surgery between 2009 and 2020. All patients had PM recurrence. Factors associated with PM-free survival (PMFS) were assessed using Cox regression. The primary endpoint was early PM recurrence defined as a PMFS of <6 months. A model (logistic regression) was fitted and corrected using bootstrap.

RESULTS

In total, 235 patients were included. The median PMFS was 13 (IQR, 8-22) months, and 15.7% of the patients experienced an early PM recurrence. Synchronous limited PM and/or ovarian metastasis (hazard ratio [HR]: 2.50; 95% confidence interval [CI]: [1.66-3.78]; p < 0.001) were associated with a very high-risk status requiring SLLE. T4 (HR: 1.47; 95% CI: [1.03-2.11]; p = 0.036), transverse tumor localization (HR: 0.35; 95% CI: [0.17-0.69]; p = 0.002), emergency surgery (HR: 2.06; 95% CI: [1.36-3.13]; p < 0.001), mucinous subtype (HR: 0.50; 95% CI [0.30, 0.82]; p = 0.006), microsatellite instability (HR: 2.29; 95% CI [1.06, 4.93]; p = 0.036), KRAS mutation (HR: 1.78; 95% CI: [1.24-2.55]; p = 0.002), and complete protocol of adjuvant chemotherapy (HR: 0.93; 95% CI: [0.89-0.96]; p < 0.001) were also prognostic factors for PMFS. Thus, a model was fitted (area under the curve: 0.87; 95% CI: [0.82-0.92]) for prediction, and a cutoff of 150 points was identified to classify patients at high risk of early PM recurrence.

CONCLUSION

Using a nomogram, eight prognostic factors were identified to select patients at high risk for early PM recurrence objectively. Patients reaching 150 points could benefit from an early SLLE.

Effect of intra-operative chemotherapy with 5-fluorouracil and leucovorin on the survival of patients with colorectal cancer after radical surgery: a retrospective cohort study

BACKGROUND

The effect of intra-operative chemotherapy (IOC) on the long-term survival of patients with colorectal cancer (CRC) remains unclear. In this study, we evaluated the independent effect of intra-operative infusion of 5-fluorouracil in combination with calcium folinate on the survival of CRC patients following radical resection.

METHODS

1820 patients were recruited, and 1263 received IOC and 557 did not. Clinical and demographic data were collected, including overall survival (OS), clinicopathological features, and treatment strategies. Risk factors for IOC-related deaths were identified using multivariate Cox proportional hazards models. A regression model was developed to analyze the independent effects of IOC.

RESULTS

Proportional hazard regression analysis showed that IOC (hazard ratio [HR]=0.53, 95% confidence intervals [CI] [0.43, 0.65], P  < 0.001) was a protective factor for the survival of patients. The mean overall survival time in IOC group was 82.50 (95% CI [80.52, 84.49]) months, and 71.21 (95% CI [67.92, 74.50]) months in non-IOC group. The OS in IOC-treated patients were significantly higher than non-IOC-treated patients ( P  < 0.001, log-rank test). Further analysis revealed that IOC decreased the risk of death in patients with CRC in a non-adjusted model (HR=0.53, 95% CI [0.43, 0.65], P  < 0.001), model 2 (adjusted for age and gender, HR=0.52, 95% CI [0.43, 0.64], P  < 0.001), and model 3 (adjusted for all factors, 95% CI 0.71 [0.55, 0.90], P  = 0.006). The subgroup analysis showed that the HR for the effect of IOC on survival was lower in patients with stage II (HR = 0.46, 95% CI [0.31, 0.67]) or III disease (HR=0.59, 95% CI [0.45, 0.76]), regardless of pre-operative radiotherapy (HR=0.55, 95% CI [0.45, 0.68]) or pre-operative chemotherapy (HR=0.54, 95% CI [0.44, 0.66]).

CONCLUSIONS

IOC is an independent factor that influences the survival of CRC patients. It improved the OS of patients with stages II and III CRC after radical surgery.

TRIAL REGISTRATION

chictr.org.cn, ChiCTR 2100043775.

Peritoneal recurrence after resection for Stage I-III colorectal cancer: A population analysis

BACKGROUND

Colorectal cancer (CRC) often recurs in the peritoneum, although the pattern of peritoneal recurrence (PR) has received less attention. We sought to describe the presentation and risk factors for PR following CRC resection.

METHODS

We performed a cohort study of patients undergoing resection of Stage I-III CRC from 2006 to 2007 using merged data from a Commission on Cancer Special Study and the National Cancer Database. We estimated the timing, method of detection, and risk factors for isolated PR.

RESULTS

Here, 8991 patients were included and isolate PR occurred in 77 (0.9%) patients. The median time to PR was 16.2 months (intrquartile range = 9.3-28.0 months) and most patients were identified via new symptoms (36.4%). Pathologic factors associated with increased odds of PR included higher T stage (T3 vs. T2, odds ratio [OR] = 4.8, 95% confidence interval [CI] = 1.5-15.7), N stage (N1 vs. N0, OR = 2.00, CI = 1.1-3.7), and signet ring (OR = 8.2, CI = 3.0-22.3) or mucinous histology (OR = 2.6, CI = 1.5-4.7).

CONCLUSIONS

The majority of PR was detected within 18 months and few were identified by surveillance. Advanced T/N stage and signet ring/mucinous histology were associated with increased odds of PR.

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.

Development and validation of a nomogram for predicting metachronous peritoneal metastasis in colorectal cancer: A retrospective study

BACKGROUND

Peritoneal metastasis (PM) after primary surgery for colorectal cancer (CRC) has the worst prognosis. Prediction and early detection of metachronous PM (m-PM) have an important role in improving postoperative prognosis of CRC. However, commonly used imaging methods have limited sensitivity to detect PM early. We aimed to establish a nomogram model to evaluate the individual probability of m-PM to facilitate early interventions for high-risk patients.

AIM

To establish and validate a nomogram model for predicting the occurrence of m-PM in CRC within 3 years after surgery.

METHODS

We used the clinical data of 878 patients at the Second Hospital of Jilin University, between January 1, 2014 and January 31, 2019. The patients were randomly divided into training and validation cohorts at a ratio of 2:1. The least absolute shrinkage and selection operator (LASSO) regression was performed to identify the variables with nonzero coefficients to predict the risk of m-PM. Multivariate logistic regression was used to verify the selected variables and to develop the predictive nomogram model. Harrell’s concordance index, receiver operating characteristic curve, Brier score, and decision curve analysis (DCA) were used to evaluate discrimination, distinctiveness, validity, and clinical utility of this nomogram model. The model was verified internally using bootstrapping method and verified externally using validation cohort.

RESULTS

LASSO regression analysis identified six potential risk factors with nonzero coefficients. Multivariate logistic regression confirmed the risk factors to be independent. Based on the results of two regression analyses, a nomogram model was established. The nomogram included six predictors: Tumor site, histological type, pathological T stage, carbohydrate antigen 125, v-raf murine sarcoma viral oncogene homolog B mutation and microsatellite instability status. The model achieved good predictive accuracy on both the training and validation datasets. The C-index, area under the curve, and Brier scores were 0.796, 0.796 [95% confidence interval (CI) 0.735-0.856], and 0.081 for the training cohort and 0.782, 0.782 (95%CI 0.690-0.874), and 0.089 for the validation cohort, respectively. DCA showed that when the threshold probability was between 0.01 and 0.90, using this model to predict m-PM achieved a net clinical benefit.

CONCLUSION

We have established and validated a nomogram model to predict m-PM in patients undergoing curative surgery, which shows good discrimination and high accuracy.

Hyperthermic intraperitoneal chemotherapy and colorectal cancer: From physiology to surgery

The pursuit of this paper is to collect principal reviews and systematic reviews about hyperthermic intraperitoneal chemotherapy (HIPEC) and cytoreductive surgery (CRS) used in colorectal cancer (CRC). We focus on principal biological aspects of CRC, hyperthermia effects, and surgical procedures. We searched PubMed/MEDLINE for the principal reviews and systematic reviews published from 2010 to 2021 regarding the bimodal treatment (CRS + HIPEC) against local and advanced CRC. In the literature, from several studies, it seems that the efficacy of bimodal treatment with an accurate CRS can extend overall survival. Despite these studies, there are not still any straight guidelines more detailed and scheduled about the use of combined treatment in patients with CRC. Even if the concept is still not very clear and shared, after a careful evaluation of the published data, and after some technical and pathophysiological descriptions, we concluded that it is possible to improve the overall survival and quality of life and to reduce the tumor relapse in patients affected by locally advanced (pT4) CRC with peritoneal metastases.

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

A Prediction Model Intended for Exploratory Laparoscopy Risk Stratification in Colorectal Cancer Patients With Potential Occult Peritoneal Metastasis

Background

The early diagnosis of occult peritoneal metastasis (PM) remains a challenge due to the low sensitivity on computed tomography (CT) images. Exploratory laparoscopy is the gold standard to confirm PM but should only be proposed in selected patients due to its invasiveness, high cost, and port-site metastasis risk. In this study, we aimed to develop an individualized prediction model to identify occult PM status and determine optimal candidates for exploratory laparoscopy.

Method

A total of 622 colorectal cancer (CRC) patients from 2 centers were divided into training and external validation cohorts. All patients’ PM status was first detected as negative on CT imaging but later confirmed by exploratory laparoscopy. Multivariate analysis was used to identify independent predictors, which were used to build a prediction model for identifying occult PM in CRC. The concordance index (C-index), calibration plot and decision curve analysis were used to evaluate its predictive accuracy and clinical utility.

Results

The C-indices of the model in the development and validation groups were 0.850 (95% CI 0.815-0.885) and 0.794 (95% CI, 0.690-0.899), respectively. The calibration curve showed consistency between the observed and predicted probabilities. The decision curve analysis indicated that the prediction model has a great clinical value between thresholds of 0.10 and 0.72. At a risk threshold of 30%, a total of 40% of exploratory laparoscopies could have been prevented, while still identifying 76.7% of clinically occult PM cases. A dynamic online platform was also developed to facilitate the usage of the proposed model.

Conclusions

Our individualized risk model could reduce the number of unnecessary exploratory laparoscopies while maintaining a high rate of diagnosis of clinically occult PM. These results warrant further validation in prospective studies.

Clinical Trial Registration

https://www.isrctn.com, identifier ISRCTN76852032

Prediction of Metachronous Peritoneal Metastases After Radical Surgery for Colon Cancer: A Scoring System Obtained from an International Multicenter Cohort

Background

Since novel strategies for prevention and treatment of metachronous peritoneal metastases (mPM) are under study, it appears crucial to identify their risk factors. Our aim is to establish the incidence of mPM after surgery for colon cancer (CC) and to build a statistical model to predict the risk of recurrence.

Patients and Methods

Retrospective analysis of consecutive pT3–4 CC operated at five referral centers (2014–2018). Patients who developed mPM were compared with patients who were PM-free at follow-up. A scoring system was built on the basis of a logistic regression model.

Results

Of the 1423 included patients, 74 (5.2%) developed mPM. Patients in the PM group presented higher preoperative carcinoembryonic antigen (CEA) [median (IQR): 4.5 (2.5–13.0) vs. 2.7 (1.5–5.9), P = 0.001] and CA 19-9 [median (IQR): 17.7 (12.0–37.0) vs. 10.8 (5.0–21.0), P = 0.001], advanced disease (pT4a 42.6% vs. 13.5%; pT4b 16.2% vs. 3.2%; P < 0.001), and negative pathological characteristics. Multivariate logistic regression identified CA 19-9, pT stage, pN stage, extent of lymphadenectomy, and lymphovascular invasion as significant predictors, and individual risk scores were calculated for each patient. The risk of recurrence increased remarkably with score values, and the model demonstrated a high negative predictive value (98.8%) and accuracy (83.9%) for scores below five.

Conclusions

Besides confirming incidence and risk factors for mPM, our study developed a useful clinical tool for prediction of mPM risk. After external validation, this scoring system may guide personalized decision-making for patients with locally advanced CC.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-022-12097-9.

Risk Factors for Synchronous Peritoneal Metastases in Colorectal Cancer: A Systematic Review and Meta-Analysis

Background

Early detection of synchronous colorectal peritoneal metastases (CPMs) is difficult due to the absence of typical symptoms and the low accuracy of imaging examinations. Increasing the knowledge of the risk factors for synchronous CPM may be essential for early diagnosis and improving their management. This study aimed to identify the risk factors for synchronous CPM.

Method

The study was registered at PROSPERO (CRD42020198548). The PubMed, Embase and Cochrane Library databases were searched for studies comparing the clinicopathological and molecular features between patients with or without synchronous CPM. The pooled data were assessed by a random-effects model.

Results

Twenty-five studies were included. A synchronous CPM was positively associated with female sex (OR 1.299; 1.118 to 1.509; P = 0.001), PROK1/PROKR2-positivity (OR 2.244; 1.031 to 4.884; P = 0.042), right-sided colon cancer (OR 2.468; 2.050 to 2.970; P < 0.001), poorly differentiated grade (OR 2.560; 1.537 to 4.265; P < 0.001), BRAF mutation (OR 2.586; 1.674 to 3.994; P < 0.001), mucinous adenocarcinoma (OR 3.565; 2.095 to 6.064; P < 0.001), signet-ring cell carcinoma (OR 4.480; 1.836 to 10.933; P = 0.001), N1-2 (OR 5.665; 3.628 to 8.848; P < 0.001), T4 (OR 12.331; 7.734 to 19.660; P < 0.001) and elevated serum CA19-9 (OR 12.868; 5.196 to 31.867; P < 0.001).

Conclusions

These evidence-based risk factors are indicators that could predict the presence of synchronous CPMs and can improve their management.

Systematic Review Registration

www.crd.york.ac.uk/prospero, identifier: CRD42020198548.

Early postoperative outcomes of staging laparoscopy for peritoneal metastases with or without pressurized intra-peritoneal aerosol chemotherapy (PIPAC)

Background

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been introduced for palliative treatment of peritoneal surface malignancies (PSM) and is currently tested also in the neoadjuvant and prophylactic setting. The aim was therefore to compare safety and tolerance of staging laparoscopy with or without PIPAC.

Methods

This retrospective analysis compared consecutive patients undergoing staging laparoscopy alone for oesogastric cancer with patients having PIPAC for suspected PSM of various origins from January 2015 until January 2020. Safety was assessed by use of the Clavien classification for complications and CTCAE for capturing of adverse events. Pain and nausea were documented by use of a visual analogue scale (VAS: 0–10: maximal intensity).

Results

Overall, 25 PIPAC procedures were compared to 24 staging laparoscopies. PIPAC procedures took a median of 35 min (IQR: 25–67) longer. Four patients experienced at least one complication in either group (p = 0.741). No differences were noted for postoperative nausea (p = 0.961) and pain levels (p = 0.156). Median hospital stay was 2 (IQR: 1–3) for PIPAC and 1 (IQR: 1–2) for the laparoscopy group (p = 0.104).

Conclusions

The addition of PIPAC did not jeopardize safety and postoperative outcomes of staging laparoscopy alone. Further studies need to clarify its oncological benefits.

Utility of Perioperative Measurement of Cell-Free DNA and Circulating Tumor DNA in Informing the Prognosis of GI Cancers: A Systematic Review

PURPOSE

Current surveillance imaging and tumor markers lack sensitivity for the early detection of recurrence in GI cancers. This study critically evaluates the current literature on the role of sequential measurement of circulating tumor DNA (ctDNA) before and after curative resection in informing recurrence.

METHODS

A systematic search using a predefined, registered protocol was conducted for studies published between January 2010 and May 2020. Included studies described patients with GI cancers treated with curative-intent surgical resection and measurement of ctDNA both before and after surgery. Patients were divided into three groups on the basis of the presence or absence of ctDNA at these time points. The primary outcome was recurrence-free survival (RFS).

RESULTS

The search yielded 3,873 articles; five met the inclusion criteria and collectively evaluated 57 patients. Pooled median RFS was 62 months (interquartile range 19 to not reached). Although median RFS was not reached in group 1 (- to -) or group 2 (+ to -), median RFS in group 3 (+ to +) was 15 months (interquartile range 9.6-60.4 months). Cox hazard ratio was 4.46 (95% CI, 1.17 to 16.99; P = .028) between group 1 and group 2, and 10.47 (95% CI, 2.91 to 37.74; P < .001) between group 2 and group 3.

CONCLUSION

Detectable ctDNA, either preoperatively or postoperatively, and its persistence after curative surgery are associated with a greater risk of recurrence and decreased RFS in GI cancers. Thus, perioperative measurement of ctDNA may be a useful postoperative risk stratification tool and guide additional therapies.

Primary and metastatic peritoneal surface malignancies

Peritoneal surface malignancies comprise a heterogeneous group of primary tumours, including peritoneal mesothelioma, and peritoneal metastases of other tumours, including ovarian, gastric, colorectal, appendicular or pancreatic cancers. The pathophysiology of peritoneal malignancy is complex and not fully understood. The two main hypotheses are the transformation of mesothelial cells (peritoneal primary tumour) and shedding of cells from a primary tumour with implantation of cells in the peritoneal cavity (peritoneal metastasis). Diagnosis is challenging and often requires modern imaging and interventional techniques, including surgical exploration. In the past decade, new treatments and multimodal strategies helped to improve patient survival and quality of life and the premise that peritoneal malignancies are fatal diseases has been dismissed as management strategies, including complete cytoreductive surgery embedded in perioperative systemic chemotherapy, can provide cure in selected patients. Furthermore, intraperitoneal chemotherapy has become an important part of combination treatments. Improving locoregional treatment delivery to enhance penetration to tumour nodules and reduce systemic uptake is one of the most active research areas. The current main challenges involve not only offering the best treatment option and developing intraperitoneal therapies that are equivalent to current systemic therapies but also defining the optimal treatment sequence according to primary tumour, disease extent and patient preferences. New imaging modalities, less invasive surgery, nanomedicines and targeted therapies are the basis for a new era of intraperitoneal therapy and are beginning to show encouraging outcomes.

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.

Prognostic factors for ovarian metastases in colorectal cancer patients

Purpose

The aim of this study was to analyze prognostic factors for ovarian metastases (OM) in colorectal cancer (CRC) using data from a Chinese center. In addition, the study aimed at developing a new clinical scoring system for prognosis of OM of CRC patients after surgery.

Patients and methods

Data of CRC patients with OM were collected from a single Chinese institution (n = 67). Kaplan-Meier analysis was used to evaluate cumulative survival of patients. Factors associated with prognosis of overall survival (OS) were explored using Cox’s proportional hazard regression models. A scoring system to determine effectiveness of prognosis was developed.

Results

Median OS values for patients with or without surgery were 22 and 7 months, respectively.

Size of OM, number of OM, peritoneal metastasis (PM), Peritoneal cancer index (PCI), and completeness of cytoreduction (CC) were associated with OS of patients through univariate analysis. Multivariate analysis using a Cox regression model showed that only CC was an independent predictor for OS. Three variables (the size of OM >15cm, PCI ≥ 10, and carcinoembryonic antigen (CEA) >30 ng/mL) assigned one point each were used to develop a risk score. The resulting score was used for prognosis of OS.

Conclusion

Surgical treatment of metastatic sites is effective and safe for CRC patients with OM. CC-0 is recommended for improved prognosis. The scoring system developed in this study is effective for prediction of OS of patients after surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02305-3.

A Prediction Model for Metachronous Peritoneal Carcinomatosis in Patients with Stage T4 Colon Cancer after Curative Resection

(1) Background: The aim of this study was to develop a prediction model for assessing individual mPC risk in patients with pT4 colon cancer. Methods: A total of 2003 patients with pT4 colon cancer undergoing R0 resection were categorized into the training or testing set. Based on the training set, 2044 Cox prediction models were developed. Next, models with the maximal C-index and minimal prediction error were selected. The final model was then validated based on the testing set using a time-dependent area under the curve and Brier score, and a scoring system was developed. Patients were stratified into the high- or low-risk group by their risk score, with the cut-off points determined by a classification and regression tree (CART). (2) Results: The five candidate predictors were tumor location, preoperative carcinoembryonic antigen value, histologic type, T stage and nodal stage. Based on the CART, patients were categorized into the low-risk or high-risk groups. The model has high predictive accuracy (prediction error ≤5%) and good discrimination ability (area under the curve >0.7). (3) Conclusions: The prediction model quantifies individual risk and is feasible for selecting patients with pT4 colon cancer who are at high risk of developing mPC.

The Landmark Series: Surgical Treatment of Colorectal Cancer Peritoneal Metastases

BACKGROUND

Peritoneal metastases (PM) are a form of metastatic spread affecting approximately 5-15% of colon cancer patients. The attitude towards management of peritoneal metastases has evolved from therapeutic nihilism towards a more comprehensive and multidisciplinary approach, in large part due to the development of cytoreductive surgery (CRS), usually coupled with heated intraperitoneal chemotherapy (HIPEC), along with the constant improvement of systemic chemotherapy of colorectal cancer. Several landmark studies, including 5 randomized controlled trials have marked the development and refinement of surgical approaches to treating colorectal cancer peritoneal metastases.

METHODS

This review article focuses on these landmark studies and their influence in 4 key areas: the evidence supporting surgical resection of peritoneal metastases, the identification and standardization of important prognostic variables influencing patient selection, the role of surgery and intraperitoneal chemotherapy in prevention of colorectal PM and the role of intraperitoneal chemotherapy as an adjuvant to surgical resection.

RESULTS

These landmark studies indicate that surgical resection of colorectal PM should be considered as a therapeutic option in appropriately selected patients and when adequate surgical expertise is available. Standardized prognostic variables including the Peritoneal Cancer Index and the Completeness of Cytoreduction Score should be used for evaluating both indications and outcomes.

CONCLUSIONS

Current evidence does not support the use of second look surgery with oxaliplatin HIPEC or prophylactic oxaliplatin HIPEC in patients with high risk colon cancer nor the use of oxaliplatin HIPEC with CRS of colorectal PM.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in the management of peritoneal surface malignancies - An evidence-based review

BACKGROUND

Traditionally, peritoneal surface malignancies (PSM) were considered terminal diseases because of their advanced nature, therefore, systemic chemotherapy was given with palliative intent only. As a result, very poor survival outcomes were observed. But with the introduction of complete Cytoreductive surgery (CRS) and Hyperthermic intraperitoneal chemotherapy (HIPEC), the scenario has changed dramatically.

METHODOLOGY

An objective electronic database search was performed in Pubmed, NLM Catalog, Google scholar, Bookshelf, and Pubmed Central published in the time period from 2000 till 2020. All the randomized studies were included. In the absence of randomized studies, both prospective and retrospective studies were included. The outcomes of HIPEC were measured in terms of median survival, disease-free survival, overall survival, complications and drug toxicities.

RESULTS

CRS and HIPEC are considered the standard of care for PMP and MPM even in the absence of level 1 evidence due to lack of an effective alternative treatment. In colorectal and gastric cancer, several phase-three trials are showing overall survival benefit in selected cases while there is a prophylactic and palliative role of HIPEC in gastric cancer. Three reported phase 3 trials showed positive results in ovarian cancer. In peritoneal sarcomatosis, the role of HIPEC is yet to be proven.

CONCLUSION

The patient selection is the key to the successful outcomes after HIPEC. HIPEC should be performed by the experienced surgeons in specialized centres with a strong critical care and intensive care support to reduce the morbidity and mortality. Ongoing trials and future directions will prove to be an indispensable arm in the oncological armamentarium.

Actual survival after resection of primary colorectal cancer: results from a prospective multicenter study

BACKGROUND

Colorectal cancer is the third most common type of cancer in the world. We characterize a cohort of patients who survived up to 5 years without recurrence and identify factors predicting the probability of cure.

METHODS

We analyzed data of patients who underwent curative intent surgery for stage I-III CRC between 2007 and 2012 and who had had been included in a large multicenter study in the Netherlands. Cure was defined as 5-year survival without recurrence. Survival data were retrieved from a national registry.

RESULTS

Analysis of data of 754 patients revealed a cure rate of 65% (n = 490). Patients with stage I disease and T1- and N0-tumor had the highest probability of cure (94%, 95% and 90%, respectively). Those with a T4-tumor or N2-tumor had the lowest probability of cure (62% and 50%, respectively). A peak in the mortality rate for older patients early in follow-up suggests early excess mortality as an explanation. A similar trend was observed for stage III disease, poor tumor grade, postoperative complications, sarcopenia, and R1 resections. Patients with stage III disease, poor tumor grade, postoperative complications, sarcopenia, and R1 resections show a similar trend for decrease in CSS deaths over time.

CONCLUSION

In the studied cohort, the probability of cure for patients with stage I-III CRC ranged from 50 to 95%. Even though most patients will be cured from CRC with standard therapy, standard therapy is insufficient for those with poor prognostic factors, such as high T- and N-stage and poor differentiation grade.

Combination of tumor cell anti-adhesion and anti-tumor effect to prevent recurrence after cytoreductive surgery in a mice model

One of the main problems of colorectal cancer is not the treatment of the primary tumor but the metastatic stage. Means of metastatic spread is the invasion of the peritoneal cavity which leads to peritoneal metastasis (PM). PM cannot be easily cured, and the current treatments is rather heavy, combining cytoreductive surgery with intravenous and intraperitoneal chemotherapy. This therapeutic procedure is associated with significant morbidity, altered patient quality of life and poor prognosis. We postulated that development of a prophylactic treatment could be of high interest in this context. In this study, we formulated an anti-adhesive thermogel which contains chemotherapeutics to play a role of a barrier against tumor cells implantation, avoiding their adhesion and treating the remaining tumor cells with chemotherapy intraperitoneally in a mice model of PM. The bioavailability of the thermogel was tested intraperitoneally in mice. No sign of toxicity was observed in terms of change in body weight, anatomopathology and blood biomarkers. In vitro experiments proved that the thermogel induced limited adhesion of the tumor cells. Loading of oxaliplatin (Ox) and 5-Fluorouracil (5-FU) into the thermogel were able to significantly decreased peritoneal carcinomatosis index (PCI) (-58%) and ascites (-70%) in a murine model of peritoneal metastases. These pre-clinical results confirmed that smart thermogel associated with standard chemotherapy 5-FU and Ox could be a good candidate to decrease the risk of tumor cell implantation during cytoreductive surgery and prevent future metastatic process.

Results of systematic second-look surgery plus hipec in perforated or pt4 colon cancer. Case series

Background

Perforated or pT4 colonic tumors have a bad prognosis with a high rate of relapse, including peritoneal relapse (20–30%). Our aim is to analyze the effectiveness of Second Look surgery (SLS) + hyperthermic intraperitoneal chemotherapy (HIPEC) in these patients for early treatment of peritoneal relapse (PR) or for preventing it.

Patients and methods

Patients previously operated for colon cancer, either pT4 or perforated (M0), with no evidence of disease at any level after adjuvant chemotherapy, who undergo systematic SLS + HIPEC (Oxaliplatin 30 min) one year after the initial surgery.

Results

Since February 2014 to July 2018, we performed SLS + HIPEC in 42 patients with M0, either pT4 (n = 33) or perforated (n = 9) colon cancer. Although during SLS there were suspicious lesions in 15 cases (37.5%), they were histologically confirmed in only 4 (9.5%). Histologically confirmed peritoneal relapse (PR) rate at SLS was 6% in pT4 (2/33) and 22.2% in perforated tumors (2/9). Prophylactic HIPEC was performed in all the cases. There was no postoperative mortality. Grade III-IV morbidity occurred in 19% (8/42). With a median follow-up of 33.8 months after primary tumor surgery, 6/42 patients (14.3%) presented peritoneal relapse (PR). 3-year peritoneal disease free survival was 86%, with 3-year disease free survival of 78.6% and 5-year overall survival (OS) of 97.4%.

Conclusion

Peritoneal relapse and survival rates are remarkable in these groups of, a priori, very bad prognosis, which could suggest a beneficial effect of HIPEC.

•

Prospective study trying to decrease peritoneal relapse in perforated or pT4 CRC.

•

20–30% of perforated or pT4 CRC develop peritoneal metastases in the follow-up.

•

We find peritoneal disease at Second Look surgery before seen in the image tests.

•

Second-Look Surgery + HIPEC decreases peritoneal relapse and gets better survival.

Peritoneal Metastases From Colorectal Cancer: Defining and Addressing the Challenges

The presence of peritoneal metastases (PM) in patients with colorectal cancer (CRC) is associated with an extremely poor prognosis. The diagnosis of PM is challenging, resulting in an underestimation of their true incidence. While surgery can be curative in a small percentage of patients, effective treatment for non-operable PM is lacking, and clinical and pre-clinical studies are relatively sparse. Here we have defined the major clinical challenges in the areas of risk assessment, detection, and treatment. Recent developments in the field include the application of organoid technology, which has generated highly relevant pre-clinical PM models, the application of diffusion-weighted MRI, which has greatly improved PM detection, and the design of small clinical proof-of-concept studies, which allows the efficient testing of new treatment strategies. Together, these developments set the stage for starting to address the clinical challenges. To help structure these efforts, a translational research framework is presented, in which clinical trial design is based on the insight gained from direct tissue analyses and pre-clinical (organoid) models derived from CRC patients with PM. This feed-forward approach, in which a thorough understanding of the disease drives innovation in its clinical management, has the potential to improve outcome in the years to come.

Conventional peritoneal cytology lacks the prognostic significance of detecting local or peritoneal recurrence in colorectal cancer: An Egyptian experience

Background and Aim

Colorectal cancer (CRC) accounts for over 8% of all deaths each year, with 1.2 million new cases diagnosed annually worldwide. It represents the seventh most common cancer in Egypt. Early detection of peritoneal metastasis is a major challenge in such cases. It helps with the decision of the immediate application of intraperitoneal chemotherapy after resection. Meta-analysis studies reported contrast evidence for a possible prognostic role of intraperitoneal free cancer cells (IPCCs) in peritoneal recurrence and survival after curative resection. In this work, we aim to evaluate the prevalence and impact of detecting free malignant cells in peritoneal fluid on survival and local recurrence and to estimate the incidence of peritoneal carcinomatosis (PC) during follow up.

Methods

Design: This was a prospective cohort study. Settings: From June 2016 to December 2018, samples were collected from 104 patients who underwent abdominal surgery for colorectal cancer in the Egyptian National Cancer Institute. A total of 96 Egyptian CRC patients who underwent curative resection were enrolled. Intraoperative peritoneal lavage was performed to detect IPCC by conventional cytology. Patients with no residual tumor after surgery and no evidence of PC were followed up for a median 14 months. The cumulative 12-month overall survival rate for patients with IPCC was 100% versus 86% for patients with negative cytology.

Results

Our results demonstrated that the prevalence of IPCC in the peritoneal lavage was 11.5%. Peritoneal and local recurrence occurred at a higher rate in patients with cytology positive lavage (9.1% vs 6.3% and 9.1% vs 3.8%, respectively), although this was statistically insignificant. Distant metastasis occurred significantly in patients with positive cytology (45.5% vs 8.9%) with P-value <0.001.The conventional cytology technique has a high specificity but less sensitivity.

Conclusions

The presence of IPCC using conventional cytology was not an independent prognostic factor for the development of PC or survival.

[Peritoneal recurrence prediction for colon cancer based on immunoexpression]

INTRODUCTION AND OBJECTIVES

Peritoneal relapse as an isolated form of recurrence in colon cancer occurs in 25% of cases during the first two years subsequent to a curative colectomy. Currently, the diagnostic limitations of imaging studies and the absence of predictive scales for peritoneal recurrence warrant "second look" surgery in high-risk patients. The aim of this study is to assess features of some epithelial-mesenchymal transition biomarkers (c-Met, IGF-1R and plexin β1) in order to predict post-surgical peritoneal colonization and develop a mathematical model to predict carcinomatous relapse.

METHODS

A retrospective study of the histopathological samples of 87 patients diagnosed with colon cancer who underwent radical resection was carried out, using immunohistochemical techniques for c-Met, IGF-1R and plexin β1. The patients were divided into two groups; those who had presented peritoneal recurrence and those who only had risk factors for this kind of relapse. Every stained sample was assessed by the rate of stained cells and immunostaining intensity. A possible association between immunohistochemical findings and peritoneal relapse was evaluated. Statistical analysis of the biomarkers with higher prognostic value allowed a risk mathematical formula to be developed based on coefficients, providing a specific value to each biomarker and patient.

RESULTS

c-Met expression in the primary tumour showed a high statistical trend (p: .074) while IGF-1 (p: .022) and plexin β1 (p: .021) revealed a significative association with peritoneal relapse. However, the multivariate analysis selected c-Met y plexin β1 as useful factors for a predictive mathematical model on peritoneal recurrence with a 75.8% sensitivity and 80.5% specificity in patients with a staining more than 50% for both biomarkers.

CONCLUSION

c-Met and plexin B1 overexpression is related to an increased risk of peritoneal relapse in cases of colon cancer where a radical resection is feasible. The encouraging outcomes of the proposed mathematical model may prove useful clinically in the identification of candidates for carcinoprophylaxis.

Metachronous peritoneal metastases following curative resection for colon cancer: Understanding risk factors and patterns of recurrence

BACKGROUND

A subset of metachronous colon cancer recurrence manifests as peritoneal metastases (PM). Risk factors for metachronous PM recurrence are not well-defined in patients with stage II or III colon cancers after curative resection and standard adjuvant treatments.

METHODS

Population data from the California Cancer Registry for patients with Stage II or III colon cancer were collected between 2004 and 2012. Multivariate analysis was used to identify factors associated with metachronous PM.

RESULTS

Of the 2077 patients with stage II or III colon cancer, female patients (odds ratio [OR] = 1.84, p = 0.02), T4 primary tumor (OR = 2.36, p = 0.02), mucinous (OR = 3.97, p < 0.01) or signet-ring histology (OR = 6.01, p = 0.01), and right-sided cancer (OR = 2.2, p < 0.01) were found with increased risk of metachronous isolated PM recurrence after curative resection. Median survival after diagnosis for patients without PM recurrence was 22 months, compared with 12 months for PM recurrence (p < 0.001).

CONCLUSION

PM recurrence groups have a worse overall survival than patients with recurrent disease in other sites. A better understanding of the tumor biology and molecular characteristics of colon cancers likely to recur as PM is needed to explain behavior and identify potential targeted therapy.

Canadian guidelines on the management of colorectal peritoneal metastases

Modern management of colorectal cancer (crc) with peritoneal metastasis (pm) is based on a combination of cytoreductive surgery (crs), systemic chemotherapy, and hyperthermic intraperitoneal chemotherapy (hipec). Although the role of hipec has recently been questioned with respect to results from the prodige 7 trial, the role and benefit of a complete crs were confirmed, as observed with a 41-month gain in median survival in that study, and 15% of patients remaining disease-free at 5 years. Still, crc with pm is associated with a poor prognosis, and good patient selection is essential. Many questions about the optimal management approach for such patients remain, but all patients with pm from crc should be referred to, or discussed with, a pm surgical oncologist, because cure is possible. The objective of the present guideline is to offer a practical approach to the management of pm from crc and to reflect on the new practice standards set by recent publications on the topic.

Clinical Efficacy and Safety of Hyperthermic Intraperitoneal Chemotherapy in Colorectal Cancer Patients at High Risk of Peritoneal Carcinomatosis: A Systematic Review and Meta-Analysis

Background: Hyperthermic intraperitoneal chemotherapy (HIPEC) is an effective measure for improving the prognosis of colorectal cancer (CRC) patients with peritoneal carcinomatosis (PC). However, the role of HIPEC in CRC patients at high risk of PC remains controversial. The current systematic review and meta-analysis aimed to evaluate the clinical efficacy and safety of HIPEC in CRC patients at high risk of PC. Methods: We performed a systematic search of PubMed, Embase, Cochrane Library, and other online databases up to July 30, 2020. The clinical data, including overall survival, disease free survival, peritoneal metastasis rate, and postoperative adverse reaction were screened and analyzed after data extraction. Risk ratios (RRs) were applied to analyze these dichotomous outcomes with a random effects model. Results: A total of 6 available clinical studies involving 603 patients were finally included. CRC patients at high risk of PC who proactively underwent HIPEC treatment showed a significantly reduced peritoneal metastasis rate (RR: 0.41, 95% CI: 0.21-0.83, P = 0.01; I ² = 58%) compared to the similarly high-risk in CRC patients who did not receive HIPEC treatment. However, in terms of overall survival (RR: 1.13, 95% CI: 0.97-1.33, P = 0.12; I ² = 77%), disease-free survival (RR: 1.10, 95% CI: 0.75-1.59, P = 0.63; I ² = 53%), progression free survival (RR: 1.85, 95% CI: 0.48-7.14, P = 0.37; I ² = 93%), and postoperative adverse reactions (RR: 0.1.07, 95% CI: 0.36-3.15, P = 0.90; I ² = 78%), there was no significant difference between the HIPEC treatment and control groups. Conclusions: Proactive HIPEC treatment did not show the expected clinical efficacy in prolonging the overall survival time, disease-free survival time, and progression-free survival time of CRC patients at high risk of PC. However, the preemptive administration of HIPEC was associated with a reduced peritoneal metastasis rate and did not cause adverse additional postoperative effects.

Factors Prognostic for Peritoneal Metastases from Colorectal Cancer Treated with Surgery

Purpose

To analysis factors prognostic for peritoneal metastases (PM) from colorectal cancer (CRC) treated with surgery using data from two sources and investigate the origin and effective treatment of ovarian metastases (OM).

Patients and Methods

Data from CRC patients with PM who had undergone surgery were collected from the Surveillance, Epidemiology, and End Results (SEER) database (n = 639) and a single Chinese institution (n = 60). Cumulative survival was evaluated by Kaplan–Meier analysis. Factors associated with overall survival (OS) and progression-free survival (PFS) prognosis were assessed using Cox’s proportional hazard regression models.

Results

Median OS values for patients who underwent surgery were 19 and 32 months in the SEER database and Chinese center, respectively. Age was an independent predictor of OS in both datasets. Signet-ring cell cancer and perineural invasion were independent predictors of inferior OS only in the SEER dataset, while completeness of cytoreduction (CC) and peritoneal carcinomatosis index were independent predictors for OS and PFS only in the Chinese center. Median OS was 24 months in CRC patients with PM alone and 36 months in those with both PM and OM (p = 0.181). Further, median PSF in patients with PM alone was 10 months, while that in individuals with both PM and OM was 20 months (p = 0.181).

Conclusion

Surgical treatment of the primary and metastatic sites is effective and safe for CRC patients with PM. CC-0 is recommended for improved prognosis. Moreover, OM should be recognized as a feature of PM, and cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy is beneficial for CRC patients with OM.

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.

Perforated Colorectal Cancer

The majority of patients with colorectal tumors will present via the elective route. However, one-fifth of patients will present as an emergency. The most common cause of emergency presentation of colorectal cancer is obstruction followed by perforation, and in many cases, patients will present with both. We discuss the management of the patient presenting with a perforated colorectal tumor covering the acute presentation and also how to deal with consequences of a perforated tumor, namely, the management of colorectal peritoneal metastasis (CPM). CPM used to be considered a terminal condition; however, a strategy of early detection of CPM, careful patient selection for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy, leads to much improved outcomes and even cure, in some patient compared with systemic chemotherapy alone.

Cytoreductive Surgery Combined with Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastasis from Colorectal Cancer

Peritoneal metastasis from colorectal cancer (PM-CRC) is used to be considered a systemic and fatal condition; however, it has been growingly accepted that PM-CRC can still be local disease rather than systemic disease as analogous to liver or lung metastasis. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is now considered an optimal treatment for PM-CRC with accumulating evidence. There is a good reason that CRS + HIPEC, widely accepted as a standard of care for pseudomyxoma peritonei (PMP), could be a viable option for PM-CRC given a similarity between PM-CRC and PMP. Recent years have also seen that modern systemic chemotherapy with or without molecular targeted agents can be effective for PM-CRC. It is possible that neoadjuvant or adjuvant chemotherapy combined with CRS + HIPEC could further improve outcomes. Patient selection, utilizing modern images and increasingly laparoscopy, is crucial. Particularly, diagnostic laparoscopy is likely to play a significant role in predicting the likelihood of achieving complete cytoreduction and assessing the peritoneal cancer index score.

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.

Second-look surgery plus hyperthermic intraperitoneal chemotherapy versus surveillance in patients at high risk of developing colorectal peritoneal metastases (PROPHYLOCHIP-PRODIGE 15): a randomised, phase 3 study

BACKGROUND

Diagnosis and treatment of colorectal peritoneal metastases at an early stage, before the onset of signs, could improve patient survival. We aimed to compare the survival benefit of systematic second-look surgery plus hyperthermic intraperitoneal chemotherapy (HIPEC), with surveillance, in patients at high risk of developing colorectal peritoneal metastases.

METHODS

We did an open-label, randomised, phase 3 study in 23 hospitals in France. Eligible patients were aged 18-70 years and had a primary colorectal cancer with synchronous and localised colorectal peritoneal metastases removed during tumour resection, resected ovarian metastases, or a perforated tumour. Patients were randomly assigned (1:1) to surveillance or second-look surgery plus oxaliplatin-HIPEC (oxaliplatin 460 mg/m², or oxaliplatin 300 mg/m² plus irinotecan 200 mg/m², plus intravenous fluorouracil 400 mg/m²), or mitomycin-HIPEC (mitomycin 35 mg/m²) alone in case of neuropathy, after 6 months of adjuvant systemic chemotherapy with no signs of disease recurrence. Randomisation was done via a web-based system, with stratification by treatment centre, nodal status, and risk factors for colorectal peritoneal metastases. Second-look surgery consisted of a complete exploration of the abdominal cavity via xyphopubic incision, and resection of all peritoneal implants if resectable. Surveillance after resection of colorectal cancer was done according to the French Guidelines. The primary outcome was 3-year disease-free survival, defined as the time from randomisation to peritoneal or distant disease recurrence, or death from any cause, whichever occurred first, analysed by intention to treat. Surgical complications were assessed in the second-look surgery group only. This study was registered at ClinicalTrials.gov, NCT01226394.

FINDINGS

Between June 11, 2010, and March 31, 2015, 150 patients were recruited and randomly assigned to a treatment group (75 per group). After a median follow-up of 50·8 months (IQR 47·0-54·8), 3-year disease-free survival was 53% (95% CI 41-64) in the surveillance group versus 44% (33-56) in the second-look surgery group (hazard ratio 0·97, 95% CI 0·61-1·56). No treatment-related deaths were reported. 29 (41%) of 71 patients in the second-look surgery group had grade 3-4 complications. The most common grade 3-4 complications were intra-abdominal adverse events (haemorrhage, digestive leakage) in 12 (23%) of 71 patients and haematological adverse events in 13 (18%) of 71 patients.

INTERPRETATION

Systematic second-look surgery plus oxaliplatin-HIPEC did not improve disease-free survival compared with standard surveillance. Currently, essential surveillance of patients at high risk of developing colorectal peritoneal metastases appears to be adequate and effective in terms of survival outcomes.

FUNDING

French National Cancer Institute.

Surgical management of recurrent colon cancer

There have been significant developments in the management of advanced and recurrent colorectal cancer in recent decades. 70% of primary colorectal tumours arise in the colon and for patients with stage I-III disease, the standard of care is surgical resection followed by adjuvant therapy where appropriate. Locoregional recurrence (LR) occurs in 4-11.5% of patients following treatment of primary colon cancer with curative intent, and can be categorised as peri-anastomotic, mesenteric/paracolic (nodal), retroperitoneal and peritoneal. Of these, peritoneal recurrence is usually recognised as the most challenging type of recurrence to manage. Patients with isolated peri-anastomotic or limited nodal recurrence in the mesentery or retroperitoneum may be curable by radical salvage surgery, which often requires en bloc multi-visceral resection, while patients with low volume peritoneal metastases may be candidates for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy. Ensuring complete resection along embryonic mesocolic planes or en bloc resection of contiguously involved structures are best strategies to reduce the likelihood of local recurrence through a R1 resection margin. The role of complete mesocolic excision (CME) with high vascular ligation has been demonstrated to increase nodal yield and improve overall survival although this is more contentious. In patients with T4a disease and serosal surface involvement, peritoneal recurrence represents the greatest threat. Efforts for early diagnosis of peritoneal recurrence in these patients or prophylactic treatment, while intuitive have not demonstrated the survival benefit that would be expected. Other than locoregional recurrence (LR), systemic recurrence may occur in up to 50% of patients who have undergone curative resection for colorectal cancer. In keeping with portal venous outflow, the most common site of systemic recurrence is the liver. Although previously thought to be a fatal condition, liver resection is now the standard of care where liver metastases can be completely resected with clear margins plus leaving an adequate liver remnant with intact vascular inflow, outflow and biliary drainage. This can usually be achieved in 26-45% of patients presenting with liver metastases. Liver surgeons at the forefront of liver resection have also developed techniques to induce liver hypertrophy so as to improve likelihood of resectability. Even where patients have non-resectable disease, ablative techniques have become increasingly common. Naturally, none of these would be possible without the advent of improved chemotherapeutic and biological options in the field of medical oncology. Pulmonary metastasectomy with curative intent may be possible in a small number (10%) of patients with lung metastases, which is associated with an overall survival of up to 40%. Unlike liver metastases, proportionally less patients with pulmonary metastases will be resectable. For these patients, several ablative options are available. For all patients with recurrent colon cancer, patient selection for radical salvage surgery and decisions surrounding treatment strategy (including use of systemic therapy or ablative procedures) should take place in a multidisciplinary team setting.

Surgical management and hyperthermic intraperitoneal chemotherapy for locally advanced colorectal cancer

Locally advanced colorectal cancers (CRC) pose several management challenges, including local recurrence and the development of peritoneal metastases (PM). These recurrences are associated with a poor prognosis and onerous complications. In selected patients with PM, cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) have shown to confer survival benefit. However, its effectiveness depends on the disease extent and this combined treatment is associated with significant morbidity. Additionally, early detection of PM is difficult even with state-of-the-art imaging techniques. Due to the high-risk of developing PM, locally advanced CRC are currently being investigated in several trials, including adjuvant HIPEC in an attempt to reduce the risk of PM. This review article sets out to examine the current data available on this topic, in an attempt to determine the suitability and effectiveness of HIPEC in the management of locally advanced CRC.

Laparoscopic surgery for T4 colon cancer: a risk factor for peritoneal recurrences?

BACKGROUND

Although some preclinical studies have inferred that laparoscopic surgery for advanced cancer may increase the risk of peritoneal metastasis, this potential hazard has not been fully evaluated in the clinical setting. This study aimed to clarify whether laparoscopic surgery is associated with an increased risk of postoperative peritoneal recurrence after resection of T4 colon cancer.

METHODS

This study included 272 patients who underwent curative resection for pathological T4a colon cancer without distant metastases at the University of Tokyo Hospital between 1997 and 2017. Multivariable Fine-Gray analysis was performed to evaluate whether the use of laparoscopy was an independent risk factor for postoperative peritoneal recurrence. Thereafter, oncological outcomes (overall and relapse-free survival, and organ-specific recurrence) were compared between laparoscopic colectomy and open colectomy using propensity score matching.

RESULTS

Multivariable analysis found that laparoscopic surgery was a significant risk factor for postoperative peritoneal recurrence (hazard ratio: 1.89; 95% confidence interval: 1.01-3.65; P = .046). Comparison after propensity score matching revealed that the incidence of peritoneal recurrence was significantly higher after laparoscopic colectomy than after open colectomy (5-year cumulative incidence: 28.1% vs 12.1%; P = .003).

CONCLUSION

This study suggested that laparoscopic surgery may be related to an increased risk of peritoneal recurrence in patients with pathological T4a colon cancer. Clinicians should be fully aware of this potential risk and seek an optimal treatment plan for the prevention and early detection of peritoneal metastasis.

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.

Colorectal peritoneal metastases: pathogenesis, diagnosis and treatment options - an evidence-based update

Peritoneal metastases confer the worst survival among all sites in patients with metastatic colorectal cancer. They develop largely through transcoelomic spread, with a sequence of events that allow cells to first detach from primary tumours, survive in the peritoneal environment, attach to the peritoneal surface of organs and migrate into the submesothelial space to create a microenvironment conducive to metastatic growth. Diagnostic challenges have previously hindered early identification of peritoneal metastases. While advances in diagnostic modalities have improved our ability to identify peritoneal metastases, lesions under 0.5 cm remain challenging to detect. The advent of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) can offer selected patients with colorectal peritoneal metastases a favourable long-term survival. Recent trials, however, have cast doubts on the efficacy of HIPEC, with the recent PRODIGE 7 trial showing no benefit from oxaliplatin based HIPEC in addition to good quality cytoreductive surgery in resectable disease. While peritoneal recurrence can be reliably predicted from high-risk features in primary tumours such as a perforated cancer, ovarian metastases or T4a cancers, the use of prophylactic second look surgery with HIPEC or adjuvant HIPEC failed to demonstrate any survival benefit in high-risk cases in recent clinical trials, raising further questions about the efficacy of HIPEC. With high failure rates from systemic chemotherapy in unresectable disease, novel surgical techniques such as pressurized intraperitoneal aerolized chemotherapy are being investigated in clinical trials worldwide. Further collaborative research is needed to explore newer avenues of treatment for this poor prognostic cohort.

Prognostic Impact of Curative Resection for Peritoneal Recurrence of Colorectal Cancer

BACKGROUND

Peritoneal recurrence (PR) of colorectal cancer is a poor prognostic factor but may be treatable by curative resection. We investigated the efficacy of this treatment and identified risk factors for postoperative recurrence.

METHODS

The subjects were patients who underwent radical surgery for colorectal cancer between January 2006 and March 2014. Those with PR were retrospectively reviewed. Prognostic factors for overall survival (OS) and risk factors for postoperative recurrence were identified.

RESULTS

Among 2256 patients, 66 had PR (2.9%). Surgical resection of PR was performed in 41 patients. Curative resection was achieved macroscopically in 38 cases without diffuse metastases in the peritoneum distant from the primary tumor and with a peritoneal cancer index < 10. In multivariate analysis, curative resection was a significant prognostic factor [hazard ratio (HR) 0.198] for better 5-year OS compared with cases without curative resection (68.7% vs. 6.3%, P < 0.001). In 28 cases with concurrent metastasis, curative resection significantly improved 5-year OS compared with no curative resection (78.7% vs. 0%, P = 0.008). In the 38 patients with curative resection, the 3-year recurrence-free survival rate was 21.4%. In multivariate analysis, concurrent metastasis was a significant risk factor [HR 3.394] for postoperative recurrence, and cases with concurrent metastasis more frequently had recurrence within 2 years after curative resection.

CONCLUSIONS

Curative resection improved the prognosis in patients with limited and resectable PR of colorectal cancer with or without concurrent metastasis. However, recurrence after curative resection was common and concurrent metastasis was a risk factor for this recurrence.

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

Background

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

Methods

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

Results

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

Conclusion

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

Perceptions in the management of colorectal peritoneal metastases: A bi-national survey of colorectal surgeons

BACKGROUND

There is great variability in the uptake of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) in the management of colorectal peritoneal metastases (CRPM) in Australia and New Zealand. This study aims to provide a snapshot of perceptions among colorectal surgeons in the management of CRPM.

METHODS

A structured ten-question online survey was sent to all colorectal surgeons, with three questions on clinical experience and demographics, one on health economics and six on hypothetical clinical scenarios. Scores were collated and reported based on Likert scales.

RESULTS

Eighty-one respondents (36.2%) completed the survey. Most surgeons (66.7%) strongly disagreed with offering CRS and HIPEC at all hospitals. The majority (87.7%) agreed that CRS and HIPEC offered a higher survival benefit than systemic chemotherapy in pseudomyxoma peritonei (PMP), and 69.1% in CRPM (comparators: 60.5% ovarian cancer, 14.8% gastric cancer). There were mixed strategies in managing low-volume, isolated peritoneal recurrences. The majority did not recommend second-look laparoscopy, but favoured operative management of Krukenberg tumours. In the presence of incidental peritoneal metastases, only 29.6% favoured biopsy only and referring the patient to a peritoneal disease centre.

CONCLUSIONS

Response rate was relatively low. In Australia and New Zealand, colorectal surgeons see a strong role for CRS and HIPEC in the management of PMP and CRPM. The role of "second look" surgery in high-risk cases is controversial and not supported. Krukenberg tumours are viewed as surgical disease. Regular updates and collaboration with peritoneal centres may help surgeons stay abreast with latest evidence in the field.