Patient selection for cytoreductive surgery in colorectal peritoneal carcinomatosis using serum tumor markers: an observational cohort study. Ann Surg. 2012;256:1078-1083. [PMID: 22580940 DOI: 10.1097/sla.0b013e318254f281]

Patterns of Preoperative Tumor Markers Can Predict Resectability and Prognosis of Peritoneal Metastases: A Clustering Analysis

BACKGROUND

Prediction of open-close and long-term outcome is challenging in patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Prognostic scores often include factors not known at baseline. Therefore, we aimed to analyze whether patterns of preoperative tumor markers could aid in prediction of open-close surgery and outcome in patients with pseudomyxoma peritonei (PMP) or colorectal peritoneal metastases (PM).

PATIENTS AND METHODS

All patients accepted for CRS and HIPEC for PMP or colorectal PM at Uppsala University Hospital in 2013-2021 were included. The tumor markers CEA, CA19-9, CA125, CA72-4, and CA15-3 were clustered using the k-means algorithm; the average silhouette width determined the optimal numbers of clusters.

RESULTS

Clustering of patients with PMP (n = 138) and colorectal PM (n = 213) resulted in two clusters each. PMPCluster-1 (n = 124) had a 5-year overall survival (OS) of 77% (95% CI 69-85%), 11 (9%) open-close surgeries, and a median peritoneal cancer index (PCI) of 17. PMPCluster-2 (n = 14) patients had poorer prognosis (36%, 95% CI 15-85%, p = 0.003), more often open-close (n = 6, 43%, p = 0.002), and higher PCI (median 36, p < 0.001). ColorectalCluster-1 (n = 191) had a 5-year OS of 28% (95% CI 21-37%), median PCI of 11, and 38 (20%) open-close surgeries. ColorectalCluster-2 (n = 22) had poorer prognosis (10%, 95% CI 3-36%, p = 0.02), higher PCI (median 26, p < 0.001), higher completeness of cytoreduction score (p = 0.005), but no difference in open-close surgery (n = 6, 27%, p = 0.411). PMPCluster-2 and ColorectalCluster-2 were characterized by markedly elevated tumor markers. Open-close surgery was unusual in cases of normal CA72-4.

CONCLUSIONS

Elevation of several preoperative tumor markers is associated with poor prognosis and increased risk of open-close. CA72-4 deserves increased attention.

Predicting Severe Postoperative Complications after CRS-HIPEC: An Externally Validated Machine-Learning Tool

INTRODUCTION

Current decision support tools designed to predict postoperative complications, following cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), are limited by small sample sizes and lack of external validation. Our aim was to develop an externally validated machine-learning tool that can predict severe complications (Clavien-Dindo grade ≥ 3) after CRS-HIPEC.

METHODS

The dataset consisted of adult patients who underwent CRS-HIPEC at the University of Pittsburgh Medical Center (UPMC) and was split into an 80:20 ratio for the training and internal validation datasets, respectively. For external validation, we used the US HIPEC collaborative dataset. Three different models were trained and tested, and SHAP values were calculated to assess variable importance.

RESULTS

A total of 37% (n = 719/1955) of cases in the UPMC cohort experienced severe postoperative complications compared to 22% (n = 134/617) in the US HIPEC collaborative dataset. Recursive feature elimination algorithm determined that the optimal performance was achieved with 15 variables. After optimization, the random forest model had the highest area under the ROC curve (AUC, 0.71) in the internal validation cohort and was chosen as the final model. The random forest model had an AUC that ranged from 0.60 to 0.73 (mean AUC, 0.65) in the external validation cohorts. Finally, the most important variables associated with severe complications were high PCI, subtotal gastrectomy, low albumin levels, small bowel resection, and high Charlson Comorbidity Index.

CONCLUSIONS

Using the largest cohort of CRS-HIPEC patients in the US, we developed and externally validated a machine-learning model that can aid with patient selection and help providers anticipate complications in the postoperative setting.

INDEPSO-ISPSM Consensus on Peritoneal Malignancies: Management of Colorectal Peritoneal Metastases

PURPOSE

This manuscript reports the results of the Indian Network for Development of Peritoneal Surface Oncology and Indian Society of Peritoneal Surface Malignancies (INDEPSO-ISPSM) consensus that aimed to provide recommendations for some important aspects management of patients with colorectal peritoneal metastases (CPM) and address some issues unique to India.

METHODS

The modified Delphi technique was used with two rounds of voting. There were 29 questions on nine main topics-the role of cytoreductive surgery (CRS), patient selection for CRS, preoperative workup, role of systemic chemotherapy (SC), CPM with other visceral metastases, molecular profile, hyperthermic intraperitoneal chemotherapy (HIPEC) and other modalities of intraperitoneal chemotherapy (IPC), prophylactic/preventive strategies, and surveillances after CRS. A consensus was achieved if anyone option received >70 votes (strong consensus >90%).

RESULTS

Forty-eight surgical (n = 41) and gastrointestinal (n = 7) oncologists were invited; 44 agreed to participate. The response rate was 95.4% (42/44) in round 1 and 93.1% (41/44) in round 2. Overall, a consensus was achieved on 23/29 (79.3%) questions (strong consensus on 6/29 [20.6%]). The panel strongly recommended considering surgery for limited CPM with limited liver metastases (92.5%), not altering the surgical approach in patients with KRAS mutations (91.67%), and limiting the use of IPC for unresectable CPM outside clinical trials (95%). Adjuvant SC was recommended for all patients undergoing CRS (89.47%). CRS is a therapeutic option for selected patients with CPM including those with metachronous CPM (79.49) and signet ring cell cancers (76.92%). HIPEC was recommended outside clinical trials only for patients with peritoneal cancer index 11-15(80%).

CONCLUSION

The panel recommended CRS for most indications but was very selective in recommending HIPEC and IPC outside clinical trials. These recommendations should be a useful resource in clinical decision making for clinicians treating CPM in India and regions with a similar sociodemographic background.

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.

Use of Prognostic Factors and Scores in Selection of Patients with Colorectal Cancer Peritoneal Metastasis (CRPM) for Cytoreductive Surgery and Intraperitoneal Chemotherapy (CRS/IPC): Results of an International Survey Among Oncologic Clinicians

BACKGROUND

No universally accepted guidelines exist for treatment of patients with colorectal cancer peritoneal metastases (CRPM) undergoing cytoreductive surgery and intraperitoneal chemotherapy (CRS/IPC). Several uncertainties remain concerning almost every aspect of this treatment modality, resulting in marked variability in patient management and likely outcomes. This survey aimed to define variations and trends in clinician decision making more clearly.

METHODS

A 41-question web-based survey was distributed electronically via the Peritoneal Surface Oncology Group International (PSOGI), the International Society for the Study of Pleura and Peritoneum (ISSPP) as well as via social media (particularly Twitter). The survey sought to address and record clinician responses regarding patient workup/assessment, selection for preoperative systemic therapy, preoperative and intraoperative selection for CRS/IPC, and consideration of prognosis and complications.

RESULTS

Complete responses were received from 60 clinicians from 45 centres in 22 countries. Upon assessment of survey responses, several interesting trends were noted in each section of the survey. Significant variability in surgeon practice and opinion were identified concerning almost every aspect of the treatment modality.

CONCLUSION

This international survey provides the most comprehensive insight into clinician decision-making trends regarding patient assessment, selection and management. This should allow areas of variability to be more clearly defined and could potentially prompt development of initiatives for achieving consensus and standardisation of care in the future.

External validation of COMPASS and BIOSCOPE prognostic scores in colorectal peritoneal metastases treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC)

INTRODUCTION

The selection of patients undergoing cytoreductive- surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is crucial. BIOSCOPE and COMPASS are prognostic scores designed to stratify survival into four classes according to clinical and pathological features. The purpose of this study is to analyze the prognostic role of these scores using a large cohort of patients as an external reference.

METHODS

Overall survival analysis was performed using Log-Rank and Kaplan-Meier curves for each score. The probability of survival at 12, 36, and 60 months was tested using receiver operating characteristic (ROC) curves to determine sensitivity and specificity.

RESULTS

From the validation cohort of 437 patients, the analysis included 410 patients in the COMPASS group and 364 patients in the BIOSCOPE group (100% data completeness). We observed a different patient distribution between classes (high-risk for BIOSCOPE compared to COMPASS, p = 0.0001). Nevertheless, both COMPASS and BIOSCOPE effectively stratified overall survival (Log-Rank, p = 0.0001 in both cases), with a lack of discrimination between COMPASS classes II and III (p = n.s.). COMPASS at 12 m and BIOSCOPE at 60 m showed the best performance in terms of survival prediction (AUC of 0.82 and 0.81). The specificity of the two tests is good (median 81.3%), whereas sensibility is quite low (median 64.2%).

CONCLUSION

Following external validation in a large population of patients with CRC-PM who are eligible for surgery, the COMPASS and BIOSCOPE scores exhibit high inter-test variability but effectively stratify cancer-related mortality risk. While the quality of the scores is similar, BIOSCOPE shows better inter-tier differentiation, suggesting that tumor molecular classification could improve test discrimination capability. More powerful stratification scores with the inclusion of novel predictors are needed.

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.

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.

Troponin measurement for risk stratification after cytoreductive surgery

Several studies have raised interest in the use of postoperative troponin levels to stratify risk of postoperative morbidity and mortality. In this study, postoperative troponin concentration after cytoreductive surgery (with or without hyperthermic intraoperative intraperitoneal chemotherapy) was associated with severe postoperative complications, and enhanced the predictive capability of a multivariable model focusing on postoperative complications.

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.

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

AIM

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

METHOD

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

RESULTS

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

CONCLUSION

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

Neutropenia in colorectal cancer treated with oxaliplatin-based hyperthermic intraperitoneal chemotherapy: An observational cohort study

BACKGROUND

The implications of neutropenia after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) treatment have never been investigated.

AIM

To evaluate the occurrence of neutropenia and its effect on the risk of increased Clavien-Dindo morbidity as well as its effect on overall or disease-free survival.

METHODS

All patients with colorectal peritoneal metastases (1996-2015) completing cytoreductive surgery and oxaliplatin-based HIPEC treatment from a bi-institutional database (Uppsala and Sydney) were included in the study. Clavien-Dindo grade 3-4 morbidity differences between the neutropenia group vs non-neutropenia group were calculated and Kaplan-Meier curves with log rank test were rendered. Univariate and multivariable Cox regression models for disease-free survival were implemented.

RESULTS

Two hundred and forty-six patients were identified - 32 postoperative any-grade neutropenia patients and 214 non-neutropenia patients. The neutropenia group had more combination oxaliplatin + irinotecan treatment than the non-neutropenia group (66% vs 13%, P = 0.0001). The neutropenia group was not associated with increased Clavien-Dindo grade 3-4 morbidity. Median overall survival was 53 mo vs 37 mo for the neutropenia and non-neutropenia group, P = 0.07. Median disease-free survival was 16 mo vs 11 mo, respectively, P = 0.02. Neutropenia was an independent prognostic factor for disease-free survival with hazard ratio: 0.58, 95% confidence interval: 0.36-0.95, P = 0.03.

CONCLUSION

13% of patients developed neutropenia which was not associated with increased Clavien-Dindo grade 3-4 morbidity. Neutropenia was an independent positive prognostic factor for disease-free survival and was associated with more intense HIPEC treatment. This is in direct contrast to the current paradigm of decreasing the treatment intensity.

The volume-time index (VTI) is prognostic in patients with colorectal cancer peritoneal metastases undergoing cytoreductive surgery and intraperitoneal chemotherapy

BACKGROUND

Peritoneal cancer index (PCI) is an important prognostic factor in colorectal cancer peritoneal metastases (CRPM), however it fails to consider the time period over which disease burden develops. The volume-time index (VTI) is the ratio between PCI and time from primary tumour resection.

METHODS

A retrospective cohort study of 182 patients managed from 1996 to 2017 was performed.

RESULTS

As stratified by high vs low VTI groups, median overall survival (OS) was 23 months (95% 17-46) vs 44 months (95% 35-72) with a difference in 5-year OS of 20.3% (95%CI 10.2-40.4) vs 40.1% (95%CI 29.7-54.1), p = 0.002. No difference in 5-year recurrence free survival (RFS) exists. On multivariable analysis, an elevated VTI was independently associated with poorer OS (adjusted HR 3.20, 95%CI 1.64-6.23, p < 0.001) and RFS (adjusted HR 1.90, 95%CI 1.10-3.29, p = 0.02).

CONCLUSION

VTI is an independent prognostic factor for OS and RFs in patients with CRPM undergoing CRS/IPC, behaving as a surrogate of tumour aggressiveness.

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.

Pretargeted radioimmunotherapy and SPECT imaging of peritoneal carcinomatosis using bioorthogonal click chemistry: probe selection and first proof-of-concept

Rationale: Pretargeted radioimmunotherapy (PRIT) based upon bioorthogonal click chemistry has been investigated for the first time in the context of peritoneal carcinomatosis using a CEA-targeting 35A7 mAb bearing trans-cyclooctene (TCO) moieties and several ¹⁷⁷Lu-labeled tetrazine (Tz) radioligands. Starting from three Tz probes containing PEG linkers of varying lengths between the DOTA and Tz groups (i.e. PEG_n = 3, 7, or 11, respectively, for Tz-1, Tz-2, and Tz-3), we selected [¹⁷⁷Lu]Lu-Tz-2 as the most appropriate for pretargeted SPECT imaging and demonstrated its efficacy in tumor growth control. Methods: An orthotopic model of peritoneal carcinomatosis (PC) was obtained following the intraperitoneal (i.p.) injection of A431-CEA-Luc cells in nude mice. Tumor growth was assessed using bioluminescence imaging. Anti-CEA 35A7 mAb was grafted with 2-3 TCO per immunoglobulin. Pretargeted SPECT imaging and biodistribution experiments were performed to quantify the activity concentrations of [¹⁷⁷Lu]Lu-Tz-1-3 in tumors and non-target organs to determine the optimal Tz probe for the PRIT of PC. Results: The pharmacokinetic profiles of [¹⁷⁷Lu]Lu-Tz-1-3 alone were determined using both SPECT imaging and biodistribution experiments. These data revealed that [¹⁷⁷Lu]Lu-Tz-1 was cleared via both the renal and hepatic systems, while [¹⁷⁷Lu]Lu-Tz-2 and [¹⁷⁷Lu]Lu-Tz-3 were predominantly excreted via the renal system. In addition, these results illuminated that the longer the PEG linker, the more rapidly the Tz radioligand was cleared from the peritoneal cavity. The absorbed radiation dose corresponding to pretargeting with 35A7-TCO followed 24 h later by [¹⁷⁷Lu]Lu-Tz-1-4 was higher for tumors following the administration of [¹⁷⁷Lu]Lu-Tz-2 (i.e. 0.59 Gy/MBq) compared to either [¹⁷⁷Lu]Lu-Tz-1 (i.e. 0.25 Gy/MBq) and [¹⁷⁷Lu]Lu-Tz-3 (i.e. 0.18 Gy/MBq). In a longitudinal PRIT study, we showed that the i.p. injection of 40 MBq of [¹⁷⁷Lu]Lu-Tz-2 24 hours after the systemic administration of 35A7-TCO significantly slowed tumor growth compared to control mice receiving only saline or 40 MBq of [¹⁷⁷Lu]Lu-Tz-2 alone. Ex vivo measurement of the peritoneal carcinomatosis index (PCI) confirmed that PRIT significantly reduced tumor growth (PCI = 15.5 ± 2.3 after PRIT vs 30.0 ± 2.3 and 30.8 ± 1.4 for the NaCl and [¹⁷⁷Lu]Lu-Tz-2 alone groups, respectively). Conclusion: Our results clearly demonstrate the impact of the length of PEG linkers upon the biodistribution profiles of ¹⁷⁷Lu-labeled Tz radioligands. Furthermore, we demonstrated for the first time the possibility of using bioorthogonal chemistry for both the pretargeted SPECT and PRIT of peritoneal carcinomatosis.

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.

Colorectal Peritoneal Metastases: A Systematic Review of Current and Emerging Trends in Clinical and Translational Research

Colorectal peritoneal metastases (CPM) are associated with abbreviated survival and significantly impaired quality of life. In patients with CPM, radical multimodality treatment consisting of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has demonstrated oncological superiority over systemic chemotherapy alone. In highly selected patients undergoing CRS + HIPEC, overall survival of over 60% has been reported in some series. These are patients in whom the disease burden is limited and where the diagnosis is made at an early stage in the disease course. Early diagnosis and a deeper understanding of the biological mechanisms that regulate CPM are critical to refining patient selection for radical treatment, personalising therapeutic approaches, enhancing prognostication, and ultimately improving long-term survivorship. In the present study, we outline three broad themes which represent critical future research targets in CPM: (1) enhanced radiological strategies for early detection and staging; (2) identification and validation of translational biomarkers for diagnostic, prognostic, and therapeutic deployment; and (3) development of optimized approaches for surgical cytoreduction as well as more precise strategies for intraperitoneal drug selection and delivery. Herein, we provide a contemporary narrative review of the state of the art in these three areas. A systematic review in accordance with PRISMA guidelines was undertaken on all English language studies published between 2007 and 2017. In vitro and animal model studies were deemed eligible for inclusion in the sections pertaining to biomarkers and therapeutic optimisation, as these areas of research currently remain in the early stages of development. Acquired data were then divided into hierarchical thematic categories (imaging modalities, translational biomarkers (diagnostic/prognostic/therapeutic), and delivery techniques) and subcategories. An interactive sunburst figure is provided for intuitive interrogation of the CPM research landscape.

Complete cytoreductive surgery plus HIPEC for peritoneal metastases from unusual cancer sites of origin: results from a worldwide analysis issue of the Peritoneal Surface Oncology Group International (PSOGI)

AIM

The aim of this study was to assess the outcomes of patients operated on for peritoneal metastases from unusual cancer sites of origin, meaning apart from peritoneal metastases (PM) from colorectal, gastric and epithelial ovarian carcinomas, pseudomyxoma peritonei and mesothelioma.

PATIENTS AND METHODS

A questionnaire concerning patients treated with cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) for PM arising from unusual cancer sites of origin was sent to all centres, which routinely performed HIPEC, through the Peritoneal Surface Oncology Group International and the RENAPE network.

RESULTS

Between September 1990 and June 2016, 850 procedures for unusual cases were performed in 781 patients, in 53 centres worldwide. Nearly two-thirds of the procedures were performed for three indications: rare ovarian carcinoma (n = 224), sarcoma (n = 189) and neuroendocrine tumours (n = 127). The median PCI was 12 [0-39]. Grade III-IV postoperative complications occurred in 272 patients (41%). Nineteen patients (2.9%) died postoperatively. After a median follow-up of 46 months, median overall survival (OS) was 39 months [33.18-44.05]. Five-year OS rate was 38.7%. For the three main indications, 5-year OS was significantly greater in patients with PM from rare ovarian carcinoma (57.7%), than that of patients with PM from neuroendocrine tumours (39.9%), and from sarcoma (29.3%) (p < 0.0001).

CONCLUSIONS

CRS and HIPEC appear to be safe and effective in patients with peritoneal metastases from unusual cancer sites of origin, especially from rare ovarian carcinomas, PM from neuroendocrine tumours. The respective roles of CRS and HIPEC remain unclear and should be evaluated.

A Perioperative Clinical Pathway Can Dramatically Reduce Failure-to-rescue Rates After Cytoreductive Surgery for Peritoneal Carcinomatosis: A Retrospective Study of 666 Consecutive Cytoreductions

OBJECTIVE

To determine whether a perioperative, standardized clinical pathway could impact the failure-to-rescue rate after cytoreductive surgery (CRS) for peritoneal carcinomatosis (PC) in a tertiary center.

SUMMARY OF BACKGROUND DATA

Morbidity and mortality remain significant after CRS for PC. Clinical pathways have been associated with better outcomes after surgery. The failure-to-rescue rate is a useful metric for evaluating quality in surgery.

MATERIALS AND METHODS

This study included 666 patients that received CRS for PC between 2009 and 2014. Starting in 2012, a standardized perioperative clinical pathway was introduced, which focused on patient selection, nutrition, renal protection, pain management, prevention, and early detection of complications. Complications were evaluated with the National Cancer Institute's Common Terminology Criteria for Adverse Events. We used multivariate analyses to evaluate clinicopathological and perioperative factors for associations with major complications and failure-to-rescue. Complication rates were compared before and after the clinical pathway implementation.

RESULTS

Major complications occurred in 341 patients (51%), leading to 15 deaths. The complication rate was similar before and after clinical pathway introduction (54.75% vs 48.9%, respectively; P = 0.138). Only prolonged surgery (longer than 240 mins) was independently associated with major complications. The failure-to-rescue rate was 4.4% for the entire period, but it significantly decreased after introducing the clinical pathway (9.02% vs 1.02%; P < 0.001). On multivariate analysis, only renal complications were associated with the failure-to-rescue.

CONCLUSION

Morbidity after CRS remains significant, but standardized management facilitated a reduction in the failure-to-rescue rate and improved the quality of care. Specific effort should be dedicated to preventing postoperative renal failure.

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

OBJECTIVE

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

SUMMARY BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Peritoneal carcinomatosis of colorectal cancer: novel clinical and molecular outcomes

BACKGROUND

The objective of this study was to identify the prognostic impact of parameters in peritoneal carcinomatosis from colorectal cancer.

METHODS

We collected data from patients treated by cytoreductive surgery and Hyperthermic Intraperitoneal Chemotherapy for peritoneal carcinomatosis secondary to colorectal cancer.

RESULTS

Ninety-one procedures were performed. In univariate analysis, an increased peritoneal cancer index was associated with decreased survival (P < .001). The presence of signet ring cells was associated to a decrease in survival from 45.8 to 12.1 months (P < .001). Microsatellite sequences instability status was the only molecular prognostic factor correlated with an increase in median disease-free survival: 12.4 vs 24.9 months (P = .01). The presence of a mucinous component was associated with a decreased of survival from 51.9 to 35.1 months (P = .02).

CONCLUSIONS

Clinical factors were affecting the survival of patients. The absence of signet ring cells and mucinous component and the presence of microsatellite sequences instability may be favorable prognostic factors.

Survival prognostic factors in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy treatment: analysis from a single oncological center

Background

The aim of our study is to analyze survival, treatment-related morbidity, and safety in our experience of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Methods

Sixty-four patients were treated. Survival curves were calculated according to the Kaplan-Meier method. Univariate and multivariate analyses were done, and Cox’s proportional hazard model was used to identify significant factors.

Results

Global 5-year overall survival was 55 %. Overall survival was also evaluated according to neutrophils to lymphocytes ratio and neutrophils to platelets ratio. Overall survival according to pre-operative serum albumin level shows a difference in the two groups (P < 0.05). We observed minor or no adverse events in 53 cases (89.8 %), while 3 patients (5.1 %) showed a grade III–IV complication and 3 post-operative deaths (5.1 %). Post-operative complication also influenced overall survival; patients in whom a minor complication occurred had a 3-year overall survival (OS) of 62 % vs. a 3-year OS of 28 % in patients who underwent a major complication (P < 0.1).

Conclusions

Hyperthermic intraperitoneal chemotherapy (HIPEC) could be a valid and feasible option for selected patients affected by gastrointestinal malignancies’ peritoneal carcinomatosis.

Pre-operative parameters could be evaluated to choose patient who could benefit from cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Progress in treatments for colorectal cancer peritoneal metastases during the years 2010-2015. A systematic review

Peritoneal metastases (PM) from colorectal cancer (CRC) were traditionally associated with bad prognosis. Only recently, cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has resulted in survival improvements. A systematic literature search between January 2010 and June 2015 was performed. Studies were selected and appraised according to predetermined criteria. Nineteen cohort studies, and thirteen comparative studies of CRS/HIPEC were included. The weighted median overall survival was 31.6 months (range 16-51). Major morbidity was 17.6-52.4% (weighted average 32.6%). Mortality was 0-8.1% (weighted average 2.9%). Additional relevant topics, such as CRC-PM prevalence, results by systemic therapies, preoperative work-up, and technical aspects were summarized through a narrative review. The recent literature suggests that CRS/HIPEC is gaining acceptance as standard of care for selected CRC-PM patients. Refinement of selection criteria, and rationalization of comprehensive systemic and local-regional management is ongoing. Prevention and early treatment of PM are new and promising options.

Computerized System for Staging Peritoneal Surface Malignancies

Background

Peritoneal surface malignancies (PSMs) are usually staged using Sugarbaker’s Peritoneal Cancer Index (PCI) and completeness of cytoreduction score (CC-s). Although these staging tools are essential for selecting patients and evaluating outcome after cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC), both scoring models lack some anatomic information, thus making staging laborious and unreliable. Maintaining Sugarbaker’s original concepts, we therefore developed a computerized digital tool, including a new anatomic scheme for calculating PCI and CC-s corresponding closely to patients’ real anatomy. Our new anatomic model belongs in a web-based application known as the PSM Staging System, which contains essential clinical and pathological data for the various PSMs currently treated.

Methods

The new digital tool for staging PSM runs on a personal computer or tablet and comprises male and female colored anatomic models for the 13 endoabdominal regions, with borders defined according to real anatomic landmarks. A drag-and-drop tool allows users to compute the PCI and CC-s, making it easier to localize and quantify disease at diagnosis and throughout treatment, and residual disease after CRS.

Conclusions

Once tested online by registered users, our computerized application should provide a modern, shareable, comprehensive, user-friendly PSM staging system. Its anatomic features, along with the drag-and-drop tool, promise to make it easier to compare preoperative and postoperative PCIs, thus improving the criteria for selecting patients to undergo CRS plus HIPEC. By specifying the size, site, and number of residual lesions after CRS plus HIPEC, our digital tool should help stratify patients into outcome classes.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-015-4966-5) contains supplementary material, which is available to authorized users.

Looking up: Recent advances in understanding and treating peritoneal carcinomatosis

Until recently, a diagnosis of peritoneal carcinomatosis was uniformly accompanied by a grim prognosis that was typically measured in weeks to months. Consequently, the management of carcinomatosis revolves largely around palliation of symptoms such as bowel obstruction, nausea, pain, fatigue, and cachexia. A prior lack of effective treatment options created the nihilistic view that currently exists and persists despite improvements in the efficacy of systemic therapy and the evolution of multimodality approaches including surgery and intraperitoneal chemotherapy. This article reviews the evolution and current state of treatment options for patients with peritoneal carcinomatosis. In addition, it highlights recent advances in understanding the molecular biology of carcinomatosis and the focus of current and future clinical trials. Finally, this article provides practical management options for the palliation of common complications of carcinomatosis. It is hoped that the reader will recognize that carcinomatosis is no longer an imminent death sentence and that through continued research and therapeutic innovation, clinicians can make an even greater impact on this form of metastatic cancer.

Extent of colorectal peritoneal carcinomatosis: attempt to define a threshold above which HIPEC does not offer survival benefit: a comparative study

BACKGROUND

The main prognostic factors after complete cytoreductive surgery (CCRS) of colorectal peritoneal carcinomatosis (PC) followed by intraperitoneal chemotherapy (IPC) are completeness of the resection and extent of the disease. This study aimed to determine a threshold value above which CCRS plus IPC may not offer survival benefit compared with systemic chemotherapy.

METHODS

Between March 2000 and May 2010, 180 patients underwent surgery for PC from colorectal cancer with intended performance of CCRS plus IPC.

RESULTS

Among the 180 patients, CCRS plus IPC could be performed for 139 patients (curative group, 77 %), whereas it could not be performed for 41 patients (palliative group, 23 %). The two groups were comparable in terms of age, gender, primary tumor characteristics, and pre- and postoperative systemic chemotherapy. The mean peritoneal cancer index (PCI) was lower in the curative group (11 ± 7) than in the palliative group (23 ± 7) (p < 0.0001). After a median follow-up period of 60 months (range 47-74 months), the 3-year overall survival (OS) rate was 52 % [95 % confidence interval (CI) 43-61 %] in the curative group compared with 7 % (95 % CI 2-25 %) in the palliative group. Comparison of the survivals for each PCI (ranging from 5 to 36) shows that OS did not differ significantly between the two groups of patients when the PCI was higher than 17 (hazard ratio 0.64; range 0.38-1.09).

CONCLUSION

This study confirmed the major prognostic impact of PC extent. When the PCI exceeds 17 in PC of colorectal origin, CCRS plus IPC does not seem to offer any survival benefit.

Cytoreductive surgery and hyperthermic intra-peritoneal chemotherapy treatment of colorectal peritoneal metastases: cohort analysis of high volume disease and cure rate

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intra-peritoneal chemotherapy (HIPEC) treatment of colorectal peritoneal metastases (PM) is an established treatment alternative. The study aim was, first, to investigate the outcome of high-volume disease defined by the peritoneal cancer index (PCI) 20; second, to report the long-term disease-free survival of patients with >5 years observation.

METHODS

Consecutive patients with colorectal PM from a prospective HIPEC database between 2004 and 2010 were included, 67 patients. Clinicopathological and outcome parameters were compared between low PCI (n = 40) and high PCI (n = 27). A subgroup analysis on patients with >5 years observation was performed (n = 32). Disease-free survival after 5 years defined cure.

RESULTS

Median overall survival (OS) was 28 months, low PCI-group 33 months versus high PCI-group 17 months (P = 0.03). Median OS of patients with complete CRS (n = 56) was 30 months, low PCI-group 37 months versus high PCI-group 27 months (P = 0.2), with 5-year survival of 31% and 21%, respectively. No difference in morbidity/mortality. The cure rate was 22% in the subgroup (7/32) and 28% in those with complete CRS (7/25). Two patients in the cured group had PCI 29 and 34.

DISCUSSION

Treatment of high-volume disease may result in long-term survival and even cure. The key is to reach a complete CRS. The overall cure rate is 22%.

Experts reviews of the multidisciplinary consensus conference colon and rectal cancer 2012: science, opinions and experiences from the experts of surgery

The first multidisciplinary consensus conference on colon and rectal cancer was held in December 2012, achieving a majority of consensus for diagnostic and treatment decisions using the Delphi Method. This article will give a critical appraisal of the topics discussed during the meeting and in the consensus document by well-known leaders in surgery that were involved in this multidisciplinary consensus process. Scientific evidence, experience and opinions are collected to support multidisciplinary teams (MDT) with arguments for medical decision-making in diagnosis, staging and treatment strategies for patients with colon or rectal cancer. Surgery is the cornerstone of curative treatment for colon and rectal cancer. Standardizing treatment is an effective instrument to improve outcome of multidisciplinary cancer care for patients with colon and rectal cancer. In this article, a review of the following focuses; Perioperative care, age and colorectal surgery, obstructive colorectal cancer, stenting, surgical anatomical considerations, total mesorectal excision (TME) surgery and training, surgical considerations for locally advanced rectal cancer (LARC) and local recurrent rectal cancer (LRRC), surgery in stage IV colorectal cancer, definitions of quality of surgery, transanal endoscopic microsurgery (TEM), laparoscopic colon and rectal surgery, preoperative radiotherapy and chemoradiotherapy, and how about functional outcome after surgery?

Comparison of prognostic scores for patients with colorectal cancer peritoneal metastases treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND

There are three prognostic scores for the cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) treatment of colorectal cancer peritoneal metastases: the newly introduced COREP (colorectal peritoneal) score, the peritoneal surface disease severity score (PSDS), and the prognostic score (PS). The aim was to determine which prognostic score had the best prognostic value.

METHODS

Between 2006 and 2010, a total of 77 patients with peritoneal metastases from colorectal cancer underwent CRS/HIPEC treatment. The COREP, PSDS, and PS scores were successfully applied to 56 patients (73 %) having sufficient data. The end points were prediction of open-and-close cases (n = 9), R1 resections (n = 41), and survival of <12 months (n = 18). Area under the receiver operating characteristic curves (accuracy) was compared. Subgroup analysis was performed on patients not previously used for the development of the COREP score (n = 24). Multivariable logistic regressions of the three end points were performed as well as Cox regression for overall survival. Furthermore, COREP and peritoneal cancer index were compared.

RESULTS

For open-and-close case prediction, accuracy for the whole group (n = 56) and subgroup (n = 24) was 87 and 88 %, respectively for COREP; 66 and 77 % for PSDS; and 68 and 78 % for PS. For R1 resection prediction, accuracy was 81 and 81 %, 76 and 78 %, and 75 and 77 %, respectively. For prediction of survival of <12 months, accuracy was 83 and 84, 54 and 67 %, and 55 and 56 %, respectively. The COREP score was the only independent prognostic factor in all four multivariable analyses. A COREP score of ≥6 identified patients with poor survival more accurately than a PCI of >20.

CONCLUSIONS

The COREP score predicted open-and-close cases, R1 resections, and poor survival better than PSDS and PS. COREP better identifies patients with poor survival than intraoperative PCI.

Peritoneal metastases from colorectal cancer: patient selection for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Cytoreductive surgery (CRS) in combination with hyperthermic intraperitoneal chemotherapy (HIPEC) is an established treatment modality for patients with pseudomyxoma peritonei. The majority of patients with pseudomyxoma who have complete tumour removal and HIPEC are cured. Over the last decade CRS for peritoneal metastasis of colorectal origin has emerged as an effective treatment strategy in carefully selected patients. Although convincing evidence is limited, available data shows promising results. The key to a successful outcome is appropriate selection of patients. In patients with extensive peritoneal disease, where complete cytoreduction is not achieved, surgical treatment may not be beneficial and might impair quality of life. In this paper we discuss the challenges of selecting patients with colorectal peritoneal metastases who are likely to benefit from CRS with HIPEC.

Carbohydrate antigen 19-9 (CA 19-9) is an independent prognostic indicator in pseudomyxoma peritonei post cytoreductive surgery and perioperative intraperitoneal chemotherapy

INTRODUCTION

Pseudomyxoma peritonei (PMP) is characteristically divided into two histopathological subtypes; disseminated peritoneal adenomucinosis (DPAM) and peritoneal mucinous carcinomatosis (PMCA). The latter is associated with a worse prognosis. However, even within the DPAM group, there is a considerable variation in outcome. In this study we investigate the role of baseline serum tumor markers CA 19-9, CEA and CA-125 in further stratifying survival.

METHODS

Over 16 years, 218 patients with PMP were treated with cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy (PIC) at our institution. A CA-125 level of >35 U/L, CA 19-9 of >40 U/mL and CEA of >3 ng/mL were considered positive or elevated outside the laboratory reference range. The impact of clinicopathologic and treatment-related variables on overall survival (OS) was analyzed with the Kaplan Meier method. Survival curves were compared using the log-rank test. Variables deemed significant by univariate analyses were entered into multivariate analysis using the Cox proportional hazards model.

RESULTS

Within the DPAM group, the 5-year survival of patients who were CA 19-9 positive versus those with normal values were 58% and 90% respectively (P<0.001). Other variables found to negatively impact on OS in univariate analyses were completeness of cytoreduction (CC) score 2/3 (P<0.001), peritoneal cancer index (PCI) >25 (P<0.001) and male gender (P=0.017). In the Cox regression model, only CA 19-9 positivity was found to be an independent prognostic factor for OS (P=0.034). In addition to marker positivity, the absolute level of CA 19-9 was also prognostically significant. In patients with CA 19-9>1,000 U/mL, the 5-year survival was 23%, in contrast to 90% in patients with CA 19-9<100 U/mL (P<0.001). In the PMCA cohort, only CC-score was found to be associated with OS (P<0.001).

CONCLUSIONS

Our study provides relevant prognostic information for the DPAM subtype in staging and prioritizing surgery; as even in apparently indolent disease, some patients have poorer survival. CA 19-9 elevation may also be useful in identifying patients who would potentially benefit from adjuvant therapy and/or closer post-operative surveillance. The potential role of CA 19-9 in mediating tumor cell adhesion and disease progression in PMP should be further investigated to deepen our understanding of the disease's inherent biological behavior. If a true relationship exists, CA 19-9 may be a conceivable target for immunotherapy.