Preoperative CA 19-9 Predicts Disease Progression in Colorectal Peritoneal Metastases Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: An Analysis from the US HIPEC Collaborative

INTRODUCTION

Patients with colorectal peritoneal metastases (CRPM) are increasingly treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Unfortunately, data identifying preoperative risk factors for poor oncologic outcomes after this procedure are limited. We aimed to determine the prognostic value of preoperative CEA, CA 125, and CA 19-9 on disease progression after CRS/HIPEC.

METHODS

Patients with CRPM treated with curative intent CRS/HIPEC from 12 participating sites in the United States from 2000 to 2017 were identified. Progression-free survival (PFS), defined as disease progression or recurrence, was the primary outcome.

RESULTS

In 279 patients who met inclusion criteria, the rate of disease progression was 63.8%, with a median PFS of 11 months (interquartile range [IQR] 5-20). Elevated CA 19-9 was associated with dismal PFS at 2 years (8.9% elevated vs. 30% not elevated, p < 0.01). In 113 patients who underwent upfront CRS/HIPEC, CA 19-9 emerged as the sole tumor marker independently predictive of worse PFS (hazard ratio [HR] 2.88, p = 0.048). In the subgroup of patients who had received neoadjuvant therapy (NAT), no variable was independently predictive of PFS. CA 19-9 levels over 37 U/ml were highly specific for accelerated disease progression after CRS/HIPEC. Lastly, there was no association between PFS and elevated CEA or CA 125.

CONCLUSIONS

Elevated CA 19-9 is associated with decreased PFS in patients with CRPM. While traditionally CEA is the main tumor marker assessed in colon cancer, we found that CA 19-9 may better inform preoperative risk stratification for poor oncologic outcomes in patients with CRPM. However, prospective studies are required to confirm this association.

External validation of prognostic scores and comparison of predictive accuracy for patients with colorectal cancer with peritoneal metastases considered for cytoreductive surgery and intraperitoneal chemotherapy

BACKGROUND AND OBJECTIVES

Prognostic scores are developed to facilitate the selection of patients with colorectal cancer peritoneal metastases (CRPM) for treatment with cytoreductive surgery (CRS) ± intraperitoneal chemotherapy (IPC). Three prominent prognostic scores are the Peritoneal Surface Disease Severity Score (PSDSS), the Colorectal Peritoneal Metastases Prognostic Surgical Score (COMPASS), and the modified COloREctal-Pc (mCOREP). We externally validate these scores and compare their predictive accuracy.

METHODS

Data from consecutive CRPM patients who underwent CRS/IPC from 1996 to 2018 was used to externally validate COMPASS, PSDSS, and mCOREP. Analysis evaluated the efficacy of each score in predicting (1) open-close laparotomy-those found at laparotomy to not be eligible for curative intent CRS/IPC, (2) surgical futility-those who underwent open-close laparotomy, palliative debulking surgery, or had an overall survival of less than 12 months, and (3) overall and recurrence-free survival (OS, RFS).

RESULTS

Prognostic scores were calculated for the 174-patient external validation cohort. COMPASS was most accurate in predicting open-close laparotomy, futile surgery, and survival (OS and RFS). Area under the curve (AUC) for open-close prediction was 0.78 (95% confidence interval, CI: 0.68-0.87), representing useful discrimination. However, AUC for futility prediction was 0.62 (95% CI: 0.52-0.71), and C-statistic for OS was 0.65 indicating only possibly helpful discrimination. C-statistic for RFS was 0.59 indicating poor discrimination.

CONCLUSION

While COMPASS showed the best statistical behavior, accuracy for several clinically relevant outcomes remains low, and thus applicability to clinical practice limited.

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.

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.

Definition and Prediction of Early Recurrence and Mortality Following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: Towards Predicting Oncologic Futility Preoperatively

INTRODUCTION

Early recurrence (ER) is a significant challenge for patients with colorectal peritoneal metastases (CRPM) following cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS HIPEC). Preoperative risk stratification for ER would improve preoperative decision making.

METHODS

We conducted a retrospective study examining patients who underwent CRS HIPEC for CRPM from 2000 to 2018. Optimal definition of ER was determined via minimum p-value approach based on differentiation of post-recurrence survival. Risk factors for ER were assessed in a derivation cohort by uni- and multivariate logistic regression. A predictive score for ER was generated using preoperative variables and validated in an independent cohort.

RESULTS

384 patients were analyzed, 316 (82%) had documented recurrence. Optimal length of post-operative RFS to distinguish ER (n = 144, 46%) vs. late recurrence (LR) (n = 172, 63%) was 8 mos (p<0.01). ER patients had shorter median OS post-CRS-HIPEC (13.6 vs. 39.4 mos, p<0.01). Preoperative BMI (OR 1.88), liver lesions (OR 1.89), progression on chemotherapy (OR 2.14), positive lymph nodes (OR 2.47) and PCI score (16-20: OR 1.7; >20: OR 4.37) were significant predictors of ER (all p<0.05). Using this model, patients were assigned risk scores from 0 to 9. Intermediate (scores 4-6) and high-risk patients (score 7-9) had observed rates of ER of 56% and 79% and overall 2-year survival rates of 27% and 0% respectively. The model showed fair discrimination (AUC 0.72) and good calibration (Hosmer-Lemeshow GOF p = 0.68).

CONCLUSIONS

ER predicts markedly worse OS following surgery. Preoperative factors can accurately stratify risk for ER and identify patients in whom CRS-HIPEC for CPRM is futile.

Development and Validation of a Prognostic Nomogram for Colorectal Cancer Patients With Synchronous Peritoneal Metastasis

Purpose

Synchronous peritoneal metastasis (S-PM) is considered a poor prognostic factor for colorectal cancer (CRC) and there is no nomogram to predict the survival of these patients. In this study, we aimed to use a multicenter data to identify the factors associated with S-PM of CRC to construct a nomogram for predicting the overall survival (OS) of these patients.

Methods

CRC patients with S-PM from two medical centers were enrolled between September 2007 and June 2017. Multivariate analysis was used to identify independent factors associated with OS for the nomogram to predict the 1-, 2-, and 3-year OS rates in the development group. The concordance index (C-index), calibration plot, relative operating characteristic (ROC) curve with area under the curve (AUC) were calculated to evaluate the performance of the nomogram in both the development and an external validation group.

Results

277 CRC patients with S-PM in the development group and 68 patients in the validation group were eligible for this study. In multivariate analysis of development group, age, carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 125 (CA125), cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and chemotherapy were independent variables for OS, based on which the nomogram was built. The C-index of the nomogram in the development and validation group was 0.701 (95% Cl, 0.666–0.736) and 0.716 (95% Cl, 0.622–0.810); demonstrating good discriminative ability. The calibration plots showed satisfactory consistency between actual observation and nomogram-predicted OS probabilities in the development and external validation group. The nomogram showed good predictive accuracy for 1-, 2-, and 3-year OS rates in both groups with AUC >0.70. An online dynamic webserver was also developed for increasing the ease of the nomogram.

Conclusions

We developed and validated a predictive nomogram with good discriminative and high accuracy to predict the OS in CRC patients with S-PM.

Effective Strategies to Predict Survival of Colorectal Peritoneal Metastases Patients Eligible for Cytoreductive Surgery and HIPEC

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), often combined with systemic therapy, can be offered to selected colorectal peritoneal metastases (PM) patients. However, clinical heterogeneity and the lack of high-level evidence challenges determination of the correct treatment strategy. This review aims to provide an overview of current strategies to predict survival of colorectal PM patients treated with CRS and HIPEC, guiding clinicians to select a suitable treatment-strategy and to inform patients about their prognosis. First, the prognostic relevance of several clinicopathological prognostic factors, such as extent of PM, location of primary tumor, histology type, and the presence of lymph node or liver metastases will be discussed. Subsequently, special attention will be given to recent developments in several aspects of tumor biology such as RAF/RAS mutations, circulating tumor DNA, immunoprofiling, and consensus molecular subtypes. Finally, currently available prognostic models to predict survival will be evaluated, concluding these models perform moderate to good, but most of them partly rely on intra-operative data. New insights in tumor biology, as well as the reliable assessment of extent of peritoneal disease by diffusion weighted MRI pose promising opportunities to establish an adequate and clinically meaningful preoperative prognostic model in the near future.

Systemic immune-inflammation index (SII): A More Promising Inflammation-Based Prognostic Marker for Patients with synchronic colorectal peritoneal carcinomatosis

Objective: Synchronic colorectal peritoneal carcinomatosis (SCRPC) was recognized as a predictor of poor prognosis. The aim of this study was to investigate the role of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and systemic immune-inflammation index (SII) on the survival outcome, which might help determine the treatment management of SCRPC patients.

Methods: A total of 103 SCRPC patients following cytoreduction surgery (CRS) and systematic chemotherapy (CT) between 1997 and 2013 in the First Affiliated Hospital of Sun Yat-sen University were retrospectively analyzed. The comparison of the clinicopathological variables and systematic inflammatory biomarkers, including NLR, PLR and SII, was performed by Chi-test and Cox regression analysis. According to the results of multivariate analysis, a prognostic nomogram was generated, and its prediction ability was measured by the concordance index (C-index). The survival curves were generated using the Kaplan-Meier method and survival comparison between groups was conducted via the log-rank test.

Results: Univariate analysis revealed that elevated NLR, PLR and SII were significantly correlate with worse survival outcome. Only low SII value was recognized as an independent favorable prognostic factor for overall survival (HR=1.772, 95% CI=1.015-3.095, P=0.044), except for NLR and PLR. The nomogram could perform well in the prediction of overall survival in SCRPC patients (c-index 0.782). Moreover, SII had strong prognostic discriminatory ability to predict survival outcome for the patients receiving completeness of cytoreduction score (CCR) 0/1 or CCR2/3, rather than NLR and PLR.

Conclusions: SII was a better inflammation factor to predict the outcomes of SCRPC patients receiving CRS and systematic CT. Low SII value was the most favorable factor benefiting from different level of CRS and it was useful for determining the appropriate treatment strategy for SCRPC patients.

Prognostic Impact of BRAF and KRAS Mutation in Patients with Colorectal and Appendiceal Peritoneal Metastases Scheduled for CRS and HIPEC

Background

KRAS and BRAF mutations are prognostic and predictive tools in metastatic colorectal cancer, but little is known about their prognostic value in patients scheduled for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Therefore, we analyzed the prognostic impact of KRAS and BRAF mutations in patients with peritoneal metastases scheduled for CRS and HIPEC.

Patients and Methods

In a consecutive series of 399 patients scheduled for CRS and HIPEC between 2009 and 2017, 111 subjects with peritoneal metastases from primaries of the appendix, colon, or rectum were analyzed for KRAS mutation and 92 for BRAF mutation.

Results

Mutation in KRAS was present in 51/111 (46%), and mutated BRAF was found in 10/92 (11%). There was no difference in overall survival between KRAS mutation tumors and KRAS wild type, whereas BRAF mutation was associated with short survival. No subject with BRAF mutation survived 2 years. On multivariate analysis, completeness of cytoreduction score (CCS, p = 0.000001), presence of signet cell differentiation (p = 0.000001), and BRAF mutation (p = 0.0021) were linked with poor prognosis.

Conclusions

BRAF mutation is a marker of poor prognosis in patients with appendiceal and colorectal peritoneal metastases scheduled for CRS and HIPEC, whereas survival outcome in subjects with mutated KRAS does not differ from wild-type KRAS. This finding suggests that those with BRAF mutation should be considered for alternative treatment options.

Mutations of RAS/RAF Proto-oncogenes Impair Survival After Cytoreductive Surgery and HIPEC for Peritoneal Metastasis of Colorectal Origin

BACKGROUND

Adequate selection of patients with peritoneal metastasis (PM) for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) remains critical for successful long-term outcomes. Factors reflecting tumor biology are currently poorly represented in the selection process. The prognostic relevance of RAS/RAF mutations in patients with PM remains unclear.

METHODS

Survival data of patients with colorectal PM operated in 6 European tertiary centers were retrospectively collected and predictive factors for survival identified by Cox regression analyses. A simple point-based risk score was developed to allow patient selection and outcome prediction.

RESULTS

Data of 524 patients with a median age of 59 years and a median peritoneal cancer index of 7 (interquartile range: 3-12) were collected. A complete resection was possible in 505 patients; overall morbidity and 90-day mortality were 50.9% and 2.1%, respectively. PCI [hazard ratio (HR): 1.08], N1 stage (HR: 2.15), N2 stage (HR: 2.57), G3 stage (HR: 1.80) as well as KRAS (HR: 1.46) and BRAF (HR: 3.97) mutations were found to significantly impair survival after CRS/HIPEC on multivariate analyses. Mutations of RAS/RAF impaired survival independently of targeted treatment against EGFR. Consequently, a simple point-based risk score termed BIOSCOPE (BIOlogical Score of COlorectal PEritoneal metastasis) based on PCI, N-, G-, and RAS/RAF status was developed, which showed good discrimination [development area under the curve (AUC) = 0.72, validation AUC = 0.70], calibration (P = 0.401) and allowed categorization of patients into 4 groups with strongly divergent survival outcomes.

CONCLUSION

RAS/RAF mutations impair survival after CRS/HIPEC. The novel BIOSCOPE score reflects tumor biology, adequately stratifies long-term outcomes, and improves patient assessment and selection.

RAS Mutation Decreases Overall Survival After Optimal Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy of Colorectal Peritoneal Metastasis: A Modification Proposal of the Peritoneal Surface Disease Severity Score

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are currently the most accepted treatment for peritoneal metastases from colorectal cancer. Restrictive selection criteria are essential to obtain the best survival benefits for this complex procedure. The most widespread score for patient selection, the peritoneal surface disease severity score (PSDSS), does not include current biological factors that are known to influence on prognosis. We investigated the impact of including RAS mutational status in the selection criteria for these patients.

METHODS

We studied the risk factors for survival by multivariate analysis using a prospective database of consecutive patients with carcinomatosis from colorectal origin treated by CRS and HIPEC in our unit from 2009 to 2017. The risk factors obtained were validated in a multicentre, international cohort, including a total of 520 patients from 15 different reference units.

RESULTS

A total of 77 patients were selected for local análisis. Only RAS mutational status (HR: 2.024; p = 0.045) and PSDSS stage (HR: 2.90; p = 0.009) were shown to be independent factors for overall survival. Early PSDSS stages I and II associated to RAS mutations impaired their overall survival with no significant differences with PSDSS stage III overall survival (p > 0.05). These results were supported by the international multicentre validation.

CONCLUSIONS

By including RAS mutational status, we propose an updated RAS-PSDSS score that outperforms PSDSS alone providing a quick and feasible preoperative assessment of the expected overall survival for patients with carcinomatosis from colorectal origin undergone to CRS + HIPEC.

Prognostic Nomogram for Disease-Specific Survival in Patients with Non-metastatic Ampullary Carcinoma After Surgery

Objective

The aim of this study was to establish and validate an individualized nomogram for predicting disease-specific survival (DSS) in patients with non-metastatic ampullary carcinoma after surgery.

Methods

The nomogram was prepared using retrospective data from the Surveillance, Epidemiology, and End Results database, and included 2022 patients (training dataset: 1276; validation dataset: 746 patients) with non-metastatic ampullary carcinoma who were surgically treated between 2004 and 2014. Cox multivariate regression was performed to identify independent risk factors. The predictive accuracy was determined using the concordance index (C-index) and calibration curves. Results were validated internally using bootstrap resampling, and externally against the validation dataset.

Results

The median follow-up for the training dataset was 25.5 months (range 1–143), the median survival time was 52 months [95% confidence interval (CI) 41.67–62.33], and the postoperative 1-, 3-, and 5-year DSS rates were 86.7%, 57.3%, and 47.2%, respectively. Univariate and multivariate regression analysis demonstrated that age, grade, tumor size, lymph node ratio, extension range, and histology were independent risk factors for DSS. The C-index of the internal validation dataset for predicting DSS was 0.70 (95% CI 0.68–0.72), which was superior to that of the American Joint Committee on Cancer staging, i.e. 0.64 (95% CI 0.62–0.66; p < 0.001). The 5-year DSS and median DSS time for the low-risk group were significantly greater than those for the high-risk group (p < 0.001).

Conclusion

Our nomogram reliably and accurately predicted DSS in patients with non-metastatic ampullary carcinoma after surgery. This model may help clinicians in their decision making.

Signet ring cell features with peritoneal carcinomatosis in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy are associated with poor overall survival

BACKGROUND

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is effective in select patients with peritoneal carcinomatosis (PC). Signet ring cell (SRC) pathology is associated with poor prognosis. The role of CRS/HIPEC in this population is unclear.

METHODS

Patients diagnosed with PC due to appendiceal (AC), colorectal (CRC), and gastric cancer (GC) undergoing CRS/HIPEC 2007-2016 were included.

RESULTS

A total of 268 patients were referred for CRS/HIPEC. Of the 204 patients who underwent complete CRS/HIPEC, 101 (49.5%) had AC, 85 (41.7%) CRC, and 18 (8.8%) GC. Patients with GC had higher rates of SRC pathology than AC and CRC: 12 (66.7%) vs 16 (15.8%) and 10 (11.7%). The 3-year survival rate after CRS/HIPEC was 5.7% for the SRC group and 66.1% for the non-SRC group (P < 0.001). This was true for both AC and CRC subgroups (P < 0.001 for both). Overall, patients with SRC were more likely to have a peritoneal carcinomatosis index (PCI) score > 15 (P = 0.046). Upon multivariate analysis of the SRC population, PCI > 20 (P = 0.007) and GC (P = 0.008) were found to be independent predictors of poor overall survival.

CONCLUSIONS

Performing CRS/HIPEC for PC from gastrointestinal malignancies presenting SRC features is recommended on patients with select diseases of appendiceal and colorectal origins.

More Synchronous Peritoneal Disease but Longer Survival in Younger Patients with Carcinomatosis from Colorectal Cancer Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Colonoscopy to detect colorectal cancer (CRC) is recommended starting at age 50 years; however, CRC rates are increasing in the prescreening population. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been proven effective in select patients with peritoneal carcinomatosis (PC) from CRC, although it has not been evaluated specifically in patients < 50 years.

METHODS

CRC patients aged < 50 years at diagnosis undergoing CRS/HIPEC 2007-2017 were compared with those aged ≥ 50 years. Age distribution was analyzed in patients undergoing colectomy alone versus CRS/HIPEC for CRC 1993-2013.

RESULTS

A total of 98 patients underwent CRS/HIPEC, of which 44% were < 50 years. Younger patients were more likely to present with synchronous peritoneal metastases (p = 0.050). Receipt of perioperative chemotherapy was comparable (p = not significant [NS]). Charlson Comorbidity Index and ECOG score were similar (p = NS). Tumor grade was similar (p = NS). Peritoneal Carcinomatosis Index, total organs resected, and anastomoses created were comparable (p = NS). Major Clavien-Dindo morbidity and LOS were similar (p = NS). Younger patients survived longer after CRS/HIPEC (p = 0.011). Demographic data from patients undergoing colectomy (n = 225) and CRS/HIPEC (n = 98) showed that age < 50 years was increasingly common with the more aggressive procedure (9% and 44% respectively, p < 0.001).

CONCLUSIONS

Younger patients with PC from CRC presented more often with peritoneal metastases at the time of diagnosis. Yet despite similar perioperative features at CRS/HIPEC, they survived longer than older patients. Patients undergoing CRS/HIPEC are overall younger than those undergoing index colectomy.

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.