Triphasic Learning Curve of Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is an effective but costly procedure for select patients with peritoneal malignancies. The impact of progression along a learning curve on the cost of these procedures is unknown.

PATIENTS AND METHODS

We performed a retrospective cohort study of patients undergoing CRS-HIPEC from 2016 to 2022 at a single quaternary center. Our study cohort was temporally divided into four equally sized volume quartiles (A, B, C, and D). We utilized cumulative sum plots and split-group analysis to characterize the institutional learning curve based on cost, operative time, length of stay, and morbidity. Multivariable linear regression was performed to estimate costs after adjusting for covariates. Bivariate analysis was performed using a Kruskal-Wallis test to compare continuous variables and a χ2 test to compare categorical variables.

RESULTS

Of 201 patients, the median age [interquartile range (IQR)] was 57 (47-65) years, 113 (56%) patients were female, 143 (71%) were white, and 107 (53%) had private insurance. Median operating room charge [US$42,639 (US$32,477-54,872), p < 0.001] varied between volume quartiles, peaking in quartile C. Stabilization was achieved for 86 cases for operating room cost, 88 cases for routine cost, 96 cases for length of stay, 103 cases for operative time, 120 cases for intensive care unit length of stay, and 150 cases for overall and serious morbidity. The actual operating room and routine costs were similar to predicted costs at the end of the study period.

CONCLUSIONS

The CRS-HIPEC learning curve is triphasic, with cost stability achieved relatively early compared with other markers of surgical proficiency.

Prognostic factors of early recurrence after complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND

Although cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) offer the potential for long-term survival in peritoneal carcinomatosis, outcomes following CRS/HIPEC vary significantly.

AIM

To identify the clinical factors associated with progression-free survival (PFS) after complete CRS/HIPEC in patients with colorectal/high-grade appendiceal, ovarian, and gastric cancers.

METHODS

We retrospectively evaluated the risk of recurrence within 1 year after CRS/HIPEC and its impact on overall survival (OS) in patients recruited between 2015 and 2020. Logistic regression models were used to assess the prognostic factors for the risk of recurrence within 1 year. Kaplan-Meier survival curves and Cox proportional hazards models were used to evaluate the association between recurrence and OS.

RESULTS

Of the 80 enrolled patients, 39 had an unfavorable PFS (< 1 year) and 41 had a favorable PFS (≥ 1 year). Simple logistic models revealed that the patients with a completeness of cytoreduction score of 0 (CC-0) or length of CRS ≤ 6 h had a favorable PFS [odds ratio (OR) = 0.141, P = 0.004; and OR = 0.361, P = 0.027, respectively]. In multiple logistic regression, achieving CC-0 was the strongest prognostic factor for a favorable PFS (OR = 0.131, P = 0.005). A peritoneal cancer index score > 12 was associated with a lower rate of achieving CC-0 (P = 0.027). The favorable PFS group had a significantly longer OS (median 81.7 mo vs 17.0 mo, P < 0.001).

CONCLUSION

Achieving CC-0 was associated with a lower early recurrence rate and improved long-term survival. This study underscores the importance of selecting appropriate candidates for CRS/HIPEC to manage peritoneal carcinomatosis.

First-line palliative systemic therapy alternated with oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy for unresectable colorectal peritoneal metastases: A single-arm phase II trial (CRC-PIPAC-II)

BACKGROUND

Palliative systemic therapy alternated with electrostatic precipitation oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy (ePIPAC) has never been prospectively investigated in patients with unresectable colorectal peritoneal metastases (CPM). The CRC-PIPAC-II study aimed to assess safety, feasibility and efficacy of such bidirectional therapy.

METHODS

This two-center, single-arm, phase II trial enrolled chemotherapy-naïve patients to undergo three treatment cycles, consisting of systemic therapy (CAPOX, FOLFOX, FOLFIRI, or FOLFOXIRI, all with bevacizumab) and oxaliplatin-based ePIPAC (92 mg/m2) with intravenous leucovorin (20 mg/m2) and 5-fluorouracil (400 mg/m2). Primary outcome were major treatment-related adverse events. Secondary outcomes included minor events, tumor response, progression-free survival (PFS) and overall survival (OS).

RESULTS

Twenty patients completed 52 treatment cycles. Fifteen major events occurred in 7 patients (35 %): 5 events (33 %) related to systemic therapy; 5 (33 %) related to ePIPAC; and 5 (33 %) were biochemical events. No treatment-related deaths occurred. All patients experienced minor events, mostly abdominal pain, nausea and peripheral sensory neuropathy. After treatment, radiological, pathological, cytological, and biochemical response was observed in 0 %, 88 %, 38 %, and 31 % of patients respectively. Curative surgery was achieved in one patient. Median PFS was 10.0 months (95 % confidence interval [CI] 8.0-13.0) and median OS was 17.5 months (95 % CI 13.0-not reached).

CONCLUSIONS

Combining palliative systemic therapy with oxaliplatin-based ePIPAC in patients with unresectable CPM was feasible and showed an acceptable safety profile. Treatment-induced response and survival are promising, yet further research is required to determine the additional value of ePIPAC to systemic therapy.

Development of a prediction model for recurrence in patients with colorectal peritoneal metastases undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

INTRODUCTION

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival outcomes for selected patients with colorectal peritoneal metastases (PM), but recurrence rates are high. The aim of this study was to develop a tool to predict recurrence in patients with colorectal PM that undergo CRS-HIPEC.

MATERIALS AND METHODS

For this retrospective cohort study, data of patients that underwent CRS-HIPEC for colorectal PM from four Dutch HIPEC centers were used. Exclusion criteria were perioperative systemic therapy and peritoneal cancer index (PCI) ≥20. Nine previously identified factors were considered as predictors: gender, age, primary tumor characteristics (location, nodal stage, differentiation, and mutation status), synchronous liver metastases, preoperative Carcino-Embryonal Antigen (CEA), and peritoneal cancer index (PCI). The prediction model was developed using multivariable Cox regression and validated internally using bootstrapping. The performance of the model was evaluated by discrimination and calibration.

RESULTS

In total, 408 patients were included. During the follow-up, recurrence of disease occurred in 318 patients (78%). Significant predictors of recurrence were PCI (HR 1.075, 95% CI 1.044-1.108) and primary tumor location (left sided HR 0.719, 95% CI 0.550-0.939). The prediction model for recurrence showed fair discrimination with a C-index of 0.64 (95% CI 0.62, 0.66) after internal validation. The model was well-calibrated with good agreement between the predicted and observed probabilities.

CONCLUSION

We developed a prediction tool that could aid in the prediction of recurrence in patients with colorectal PM who undergo CRS-HIPEC.

Metastatic Colorectal Cancer Treated with Combined Liver Resection, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy (HIPEC): Predictive Factors for Early Recurrence

BACKGROUND

Selection of colorectal cancer patients with concomitant peritoneal (PM) and liver metastases (LM) for radical treatment with cytoreductive surgery (CRS), including liver resection and hyperthermic intraperitoneal chemotherapy (HIPEC), needs improvement. This retrospective, monocentric study was designed to evaluate the predictive factors for early recurrence, disease-free survival (DFS), and overall survival (OS) in such patients treated in a referral center.

METHODS

Consecutive colorectal cancer patients with concomitant LM and PM treated with curative intent with perioperative systemic chemotherapy, simultaneous complete CRS, liver resection, and HIPEC in 2011-2022 were included. Clinical, radiological (before and after preoperative chemotherapy), surgical, and pathological data were investigated, along with long-term oncologic outcomes. A multivariate analysis was performed to identify predictive factors associated with early recurrence (diagnosed <6 months after surgery), DFS, and OS.

RESULTS

Of more than 61 patients included, 31 (47.1%) had pT4 and 27 (40.9%) had pN2 primary tumors. Before preoperative chemotherapy, the median number of LM was 2 (1-4). The median surgical PCI (peritoneal carcinomatosis index) was 3 (5-8.5). The median DFS and OS were 8.15 (95% confidence interval [CI] 5.5-10.1) and 34.1 months (95% CI 28.1-53.5), respectively. In multivariate analysis, pT4 (odds ratio [OR] = 4.14 [1.2-16.78], p = 0.032]) and pN2 (OR = 3.7 [1.08-13.86], p = 0.042) status were independently associated with an early recurrence, whereas retroperitoneal lymph node metastasis (hazard ratio [HR] = 39 [8.67-175.44], p < 0.001) was independently associated with poor OS.

CONCLUSIONS

In colorectal cancer patients with concomitant PM and LM, an advanced primary tumor (pT4 and/or pN2) was associated with a higher risk of early recurrence following a radical multimodal treatment, whereas RLN metastases was strongly detrimental for OS.

Prognostic value of specific KRAS mutations in patients with colorectal peritoneal metastases

BACKGROUND

There is little evidence on KRAS mutational profiles in colorectal cancer (CRC) peritoneal metastases (PM). This study aims to determine the prevalence of specific KRAS mutations and their prognostic value in a homogeneous cohort of patients with isolated CRC PM treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

MATERIALS AND METHODS

Data were collected from 13 Italian centers, gathered in a collaborative group of the Italian Society of Surgical Oncology. KRAS mutation subtypes have been correlated with clinical and pathological characteristics and survival [overall survival (OS), local (peritoneal) disease-free survival (LDFS) and disease-free survival (DFS)].

RESULTS

KRAS mutations occurred in 172 patients (47.5%) out of the 362 analyzed. Two different prognostic groups of KRAS mutation subtypes were identified: KRASMUT1 (G12R, G13A, G13C, G13V, Q61H, K117N, A146V), median OS > 120 months and KRASMUT2 (G12A, G12C, G12D, G12S, G12V, G13D, A59E, A59V, A146T), OS: 31.2 months. KRASMUT2 mutations mainly occurred in the P-loop region (P < 0.001) with decreased guanosine triphosphate (GTP) hydrolysis activity (P < 0.001) and were more frequently related to size (P < 0.001) and polarity change (P < 0.001) of the substituted amino acid (AA). When KRASMUT1 and KRASMUT2 were combined with other known prognostic factors (peritoneal cancer index, completeness of cytoreduction score, grading, signet ring cell, N status) in multivariate analysis, KRASMUT1 showed a similar survival rate to KRASWT patients, whereas KRASMUT2 was independently associated with poorer prognosis (hazard ratios: OS 2.1, P < 0.001; DFS 1.9, P < 0.001; LDFS 2.5, P < 0.0001).

CONCLUSIONS

In patients with CRC PM, different KRAS mutation subgroups can be determined according to specific codon substitution, with some mutations (KRASMUT1) that could have a similar prognosis to wild-type patients. These findings should be further investigated in larger series.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastases from Colorectal Cancer-An Overview of Current Status and Future Perspectives

Peritoneal metastases (PM) are observed in approximately 8% of patients diagnosed with colorectal cancer, either synchronously or metachronously during follow-up. PM often manifests as the sole site of metastasis. PM is associated with a poor prognosis and typically shows resistance to systemic chemotherapy. Consequently, there has been a search for alternative treatment strategies. This review focuses on the global evolution of the combined approach involving cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for the management of PM. It encompasses accepted clinical guidelines, principles for patient selection, surgical and physiological considerations, biomarkers, pharmacological protocols, and treatment outcomes. Additionally, it integrates the relevant literature and findings from previous studies. The role of CRS and HIPEC, in conjunction with other therapies such as neoadjuvant and adjuvant chemotherapy, is discussed, along with the management of patients presenting with oligometastatic disease. Furthermore, potential avenues for future development in this field are explored.

Targeted delivery of cathepsin-activatable near-infrared fluorescence probe for ultrahigh specific imaging of peritoneal metastasis

Inadequate cytoreductive surgery (CRS) has been identified as a prognostic factor for poor patient outcomes in cases of peritoneal metastasis. While imaging probes are used to identify peritoneal metastasis to facilitate CRS, many of these probes exhibit high background signals, resulting in a significant delay in achieving a satisfactory tumor-to-normal ratio (TNR) due to prolonged clearance time. In this study, we designed a novel fluorescent probe named Tras-AA-Cy NH2, which enables the relatively rapid imaging of subcutaneous tumors and peritoneal tumors while maintaining a high TNR. Mechanistically, Tras-AA-Cy NH2 exhibits selective targeting towards the Human epidermal growth factor receptor 2 on the surface of cancer cells. Following internalization, it undergoes enzymatic cleavage catalyzed by the overexpressed cathepsin, leading to the subsequent release of near-infrared fluorophores. Consequently, Tras-AA-Cy NH2 achieved a TNR of 7.8 at 6 h and 21.4 at 24 h in subcutaneous tumor mice. Even after 522 h of in vivo circulation, the TNR remained above 5, indicating an ultralong imaging time window. It is noteworthy that Tras-AA-Cy NH2 has demonstrated successful utilization for peritoneal tumor-specific imaging and further affirmed its tumor tissue-specific recognition capability using human resected tissues. In summary, these findings underscore the rational design of Tras-AA-Cy NH2 for visualizing peritoneal tumors.

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.

Effect of BRAF mutation on the prognosis for patients with colorectal cancer undergoing cytoreductive surgery for synchronous peritoneal metastasis

Background

KRAS/BRAF mutations (mutKRAS/mutBRAF) are unfavorable prognostic factors for colorectal cancer (CRC) metastases to the liver and lungs. However, their effects on the prognosis for patients with synchronous peritoneal metastasis (S-PM) of CRC after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are controversial. In the study, we aimed to determine the effects of mutKRAS/mutBRAF on the prognosis for patients with S-PM who received CRS.

Methods

A total of 142 patients diagnosed with S-PM between July 2007 and July 2019 were included in this study. The demographics, mutKRAS/mutBRAF status, overall survival (OS), and progression-free survival (PFS) of the patients were evaluated. The Kaplan-Meier method and log-rank test were used to estimate the difference in survival between groups.

Results

Among 142 patients, 68 (47.9%) showed mutKRAS and 42 (29.5%) showed mutBRAF. The median OS values were 8.4 and 34.3 months for patients with mutBRAF and BRAF wild-type, respectively (P < 0.01). However, KRAS status was not significantly associated with median OS (P = 0.76). Multivariate analysis revealed carcinoembryonic antigen, CRS, HIPEC, and mutBRAF as independent predictors for OS. Based on these findings, a nomogram was constructed. The C-index was 0.789 (95% confidence interval, 0.742-0.836), indicating good predictive ability of the model. Furthermore, the 1- and 2-year survival calibration plots showed good agreement between the predicted and actual OS rates. The area under curves of the 1- and 2-year survival predictions based on the nomogram were 0.807 and 0.682, respectively. Additionally, mutBRAF was significantly associated with lower PFS (P < 0.001).

Conclusions

mutBRAF is an independent prognostic risk factor for S-PM. The established nomogram predicted the OS of patients with CRC having S-PM with high accuracy, indicating its usefulness as a valuable prognostic tool for the designated patient cohort.

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.

Stage IV Colorectal Cancer Management and Treatment

(1) Background: Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related mortality worldwide. Up to 50% of patients with CRC develop metastatic CRC (mCRC). Surgical and systemic therapy advances can now offer significant survival advantages. Understanding the evolving treatment options is essential for decreasing mCRC mortality. We aim to summarize current evidence and guidelines regarding the management of mCRC to provide utility when making a treatment plan for the heterogenous spectrum of mCRC. (2) Methods: A comprehensive literature search of PubMed and current guidelines written by major cancer and surgical societies were reviewed. The references of the included studies were screened to identify additional studies that were incorporated as appropriate. (3) Results: The standard of care for mCRC primarily consists of surgical resection and systemic therapy. Complete resection of liver, lung, and peritoneal metastases is associated with better disease control and survival. Systemic therapy now includes chemotherapy, targeted therapy, and immunotherapy options that can be tailored by molecular profiling. Differences between colon and rectal metastasis management exist between major guidelines. (4) Conclusions: With the advances in surgical and systemic therapy, as well as a better understanding of tumor biology and the importance of molecular profiling, more patients can anticipate prolonged survival. We provide a summary of available evidence for the management of mCRC, highlighting the similarities and presenting the difference in available literature. Ultimately, a multidisciplinary evaluation of patients with mCRC is crucial to selecting the appropriate pathway.

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.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy with Intra-Operative Radiotherapy for Patients with Locally Advanced or Locally Recurrent Rectal Cancer and Peritoneal Metastases

Purpose: To assess the safety and long-term outcome of a multimodality treatment consisting of radical surgery, intra-operative radiotherapy (IORT), and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for patients with locally advanced rectal cancer (LARC) or locally recurrent rectal carcinoma (LRRC) and peritoneal metastases (PM). Methods: The present study was a single-center cohort study, including all consecutive patients undergoing this treatment in a tertiary referral center for LARC, LRRC, and PM. Postoperative complications, intensive care stay (ICU stay), and re-admission rates were assessed as well as disease-free survival (DFS) and overall survival (OS). Results: A total of 14 LARC and 16 LRRC patients with PM were included in the study. The median ICU stay was 1 day, and 57% of patients developed a severe postoperative complication. No 90-day mortality was observed. Median DFS was 10.0 months (Interquartile Range 7.1-38.7), and median OS was 31.0 months (Interquartile Range 15.9-144.3). Conclusions: As postoperative complications and survival were in line with treatments that are accepted for LARC or LRRC and PM as separate procedures, we conclude that combined treatment with IORT and CRS-HIPEC should be considered as a treatment option for selected patients with LARC or LRRC and peritoneal metastases in tertiary referral centers.

Validation of a Nomogram to Predict Recurrence in Patients with Mucinous Neoplasms of the Appendix with Peritoneal Dissemination After Cytoreductive Surgery and HIPEC

BACKGROUND

Survival of patients affected by mucinous appendiceal neoplasms with peritoneal dissemination (PD) is mainly related to histopathological features. However, prognostic stratification is still a concern, as the clinical course of the disease is often unpredictable. The aim of this study is to construct and externally validate a nomogram predicting disease-free survival (DFS) in mucinous appendiceal neoplasms with PD treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

PATIENTS AND METHODS

Patients treated in two referral centers were included: Hospital General Universitario Gregorio Marañón, Madrid, Spain (derivation cohort) and Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy (validation cohort). Cox regression analysis identified factors associated with shorter DFS in the derivation cohort. The nomogram performance was externally evaluated in the validation cohort using concordance index and calibration plots. Histology was classified according to the Peritoneal Surface Oncology Group International (PSOGI).

RESULTS

The derivation cohort included 95 patients, and the validation cohort 348. Five-year DFS rates were 51.5 and 62%, respectively. Cox regression analysis (derivation cohort) identified PSOGI histology of the peritoneal components, number of preoperative elevated tumor marker, and peritoneal disease extent, as assessed by peritoneal carcinomatosis index, to be predictors of DFS. The model's predictive capacity was higher than that of PSOGI classification alone, with respective concordance indexes of 0.702 ± 0.023 and 0.610 ± 0.018 (validation cohort). The nomogram approximated the perfect model in the calibration plots at 3- and 5-year DFS.

CONCLUSIONS

An easy-to-use model that provides better prognostic stratification than histopathological features has been constructed. This nomogram may help clinicians in individualized survival predictions and informed clinical decision-making.

Development and Validation of a Novel Prognostic Nomogram Combined With Desmoplastic Reaction for Synchronous Colorectal Peritoneal Metastasis

Purpose

The prognostic value of desmoplastic reaction (DR) has not been investigated in colorectal cancer (CRC) patients with synchronous peritoneal metastasis (SPM). The present study aimed to identify whether DR can predict overall survival (OS) and develop a novel prognostic nomogram.

Methods

CRC patients with SPM were enrolled from a single center between July 2007 and July 2019. DR patterns in primary tumors were classified as mature, intermediate, or immature according to the existence and absence of keloid-like collagen or myxoid stroma. Cox regression analysis was used to identify independent factors associated with OS and a nomogram was developed subsequently.

Results

One hundred ninety-eight and 99 patients were randomly allocated into the training and validation groups. The median OS in the training group was 36, 25, and 12 months in mature, intermediate, and immature DR categories, respectively. Age, T stage, extraperitoneal metastasis, differentiation, cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and DR categorization were independent variables for OS, based on which the nomogram was developed. The C-index of the nomogram in the training and validation groups was 0.773 (95% CI 0.734–0.812) and 0.767 (95% CI 0.708–0.826). The calibration plots showed satisfactory agreement between the actual outcome and nomogram-predicted OS probabilities in the training and validation cohorts.

Conclusions

DR classification in the primary tumor is a potential prognostic index for CRC patients with SPM. The novel prognostic nomogram combined with DR classification has good discrimination and accuracy in predicting the OS for CRC patients with SPM.

Differences in the distribution of peritoneal metastases in right- versus left-sided colon cancer on MRI

PURPOSE

Right-sided colon tumors with peritoneal metastases (PM) are associated with a poorer prognosis than left-sided tumors. We hypothesized that a different pattern of spread could be characterized with abdominopelvic MRI. The objective of this study was to explore the spread of PM in relation to the primary tumor location on MRI.

METHODS

This is a retrospective cohort study of patients with PM from colon cancer referred to be considered for CRS-HIPEC at a single tertiary referral center. Patients with colon cancer were eligible if they had undergone an abdominopelvic MRI scan following a clinical diagnosis of PM. The frequency of affected PCI regions on MRI (MRI-PCI) was assessed and compared between tumor sidedness.

RESULTS

One hundred eighteen patients were included with a median age of 65 (IQR: 56-72). 46% percent were male. The median MRI-PCI was 10 (IQR: 5-16) and 8 (IQR: 4-11) for right- and left-sided tumors, respectively (p = 0.39), and the median number of affected regions was 4 (IQR: 2-7 for right-sided and IQR 2-5 for left-sided tumors). PM was most frequently found close to the primary tumor. The odds ratio of patients with PM of left sided to be affected with PM in the upper abdominal regions was 0.42 (95% CI: 0.20-0.90) and with PM on the small bowels or mesentery was 0.42 (95% CI: 0.19-0.92) over a patient with PM of right-sided colon cancer.

CONCLUSION

MRI can help to assess the spread of PM in colonic cancer. In right-sided tumors, the small bowel and upper abdominal regions are more frequently affected.

Effect of HIPEC on Peritoneal Recurrence in Peritoneal Metastasis Treated With Cytoreductive Surgery: A Systematic Review

BACKGROUND

Peritoneal metastasis (PM) is a late-stage manifestation of intra-abdominal malignancies. The current standard of care indicates that cure can only be achieved with cytoreductive surgery (CRS) which is often indicated with concurrent adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC). However, the utility of HIPEC within subsets of PM is not fully understood. We seek to compare the effectiveness of HIPEC in improving peritoneal recurrence rates in PM of different origins.

METHODS

We conducted a systematic review of trials on the PubMed, EMBASE, and Cochrane databases, last searched in August 2021. Biases were assessed using the Cochrane Collaboration's tool for assessing the risk of bias in randomized trials as well as the Methodological Index for Non-Randomized Studies (MINORS) framework.

RESULTS

7 gastric PM studies, 3 ovarian PM studies, and 3 colorectal PM studies were included. Recurrence-free survival was improved in the HIPEC + CRS cohort in 5 gastric trials but only 1 ovarian trial and none of colorectal origin.

DISCUSSION

Our findings indicate decent effectiveness of HIPEC in gastric PM, but limited utility in ovarian and colorectal PM. Limitations in the current literature are attributed to the paucity of data available, a lack of homogeneity and consideration of novel and personalised treatment regimens. We implore for further studies to be conducted with a focus on patient selection and stratification, and suggest a reframing of approach towards modern molecular and targeted therapeutic options in future studies of HIPEC.

SYSTEMATIC REVIEW REGISTRATION

https://www.researchregistry.com/browse-the-registry#registryofsystematicreviewsmeta-analyses/registryofsystematicreviewsmeta-analysesdetails/60c1ffff0c1b78001e8efbe3/, identifier reviewregistry1166.

Fluorescence-guided surgery in colorectal cancer; A review on clinical results and future perspectives

BACKGROUND

Colorectal cancer is the fourth most diagnosed malignancy worldwide and surgery is one of the cornerstones of the treatment strategy. Near-infrared (NIR) fluorescence imaging is a new and upcoming technique, which uses an NIR fluorescent agent combined with a specialised camera that can detect light in the NIR range. It aims for more precise surgery with improved oncological outcomes and a reduction in complications by improving discrimination between different structures.

METHODS

A systematic search was conducted in the Embase, Medline and Cochrane databases with search terms corresponding to 'fluorescence-guided surgery', 'colorectal surgery', and 'colorectal cancer' to identify all relevant trials.

RESULTS

The following clinical applications of fluorescence guided surgery for colorectal cancer were identified and discussed: (1) tumour imaging, (2) sentinel lymph node imaging, (3) imaging of distant metastases, (4) imaging of vital structures, (5) imaging of perfusion. Both experimental and FDA/EMA approved fluorescent agents are debated. Furthermore, promising future modalities are discussed.

CONCLUSION

Fluorescence-guided surgery for colorectal cancer is a rapidly evolving field. The first studies show additional value of this technique regarding change in surgical management. Future trials should focus on patient related outcomes such as complication rates, disease free survival, and overall survival.

Lymph Node Metastases from Visceral Peritoneal Colorectal Metastases are Associated with Systemic Recurrence

BACKGROUND

Visceral peritoneal colorectal metastases (VPCMs) may further metastasize to lymph nodes that drain those organs. The rate of lymph node metastases (LNMs) from VPCMs and their clinical and prognostic significance are unknown.

METHODS

This study retrospectively analyzed the authors' institutional databases of 160 patients with peritoneal colorectal metastases who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Patients with LNM-VPCM (n = 12) were identified by pathologic reports, and both their short- and long-term outcomes were compared with those of patients without LNM-VPCM.

RESULTS

The clinical presentation and primary tumor pathologic characteristics did not differ between the two groups. The patients with LNM-VPCM had a higher tumor burden (measured by the peritoneal carcinomatosis index [PCI]) and visible remnant disease compared with those who had no LNM-VPI (10 vs 5.5 [p = 0.03] vs 33.3% vs 6.8% [p = 0.007], respectively). The postoperative outcomes also were comparable. The patients with LNM-VPCM had a shorter overall survival (OS) than those without LNM-VPCM (median OS, 22.5 months; 95% confidence interval [CI], 15.1-29.9 months vs 40.1 months; 95% CI, 38.1-42 months; p = 0.02). However, only tumor grade and PCI were predictors of OS in the multivariate analysis (hazard ratio [HR], 2.33 [p = 0.001]; 1.77 [p = 0.03], respectively). The study showed that LNM-VPCM was associated with systemic but not peritoneal recurrence compared with non-LNM-VPCM (81.8% vs 51.6% for systemic recurrence, respectively; p = 0.05).

CONCLUSION

The small distinct group of patients defined by LNM-VPCM were prone to systemic recurrence. Given its correlation with systemic recurrence, LNM-VPCM may indicate the need for adjuvant treatment.

Prognostic Value of KRAS Gene Mutation on Survival of Patients with Peritoneal Metastases of Colorectal Adenocarcinoma

Objective

The main objective of the study was to determine the effect of the presence of mutation in the KRAS gene on the survival in patients with colorectal cancer (CRC) and peritoneal metastases (PM).

Materials and Methods

A retrospective cohort study was performed. Patients diagnosed with CRC with synchronous or metachronous PM between January 2006 and December 2019 were included. Data on the histopathological, clinical, and treatment factors were collected. The effect of each variable on survival was evaluated by Cox regression.

Results

A total of 149 patients were included (64 women (43%) and 85 men (57%); mean age, 63 years). The long-term survival rate at 36 months was 24% (median, 21 months). KRAS mutation was detected in 75 patients (50.3%). Kaplan-Meier analysis estimated that likelihood of survival was higher in patients with wild-type KRAS tumours (35%) than in mutated-type KRAS (14%) (median: 28 vs. 15, respectively) (P=0.001). Within the categories into which the peritoneal cancer index (PCI) was classified, survival at 36 months depended on the KRAS status. Survival in wild-type KRAS tumours with PCI 1-10 was 71% and with PCI 11-20 was 26%, while in mutant-type KRAS tumours, survival was 41% and 4%, respectively (P=0.025). In the multiple regression analysis, the KRAS mutation was revealed to have an independent prognostic value (HR: 2.144; 95% CI: 1.342-3.424).

Conclusion

The mutational status of the KRAS gene has demonstrated a strong association with survival and prognostic utility in patients with CRC with PM.

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.

The Characteristics of 206 Long-Term Survivors with Peritoneal Metastases from Colorectal Cancer Treated with Curative Intent Surgery: A Multi-Center Cohort from PSOGI

Simple Summary

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy improves survival in selected patients with peritoneal metastases from colorectal cancer (CRC). However, the characteristics of long-term survivors are not well documented. This study set out to investigate the patient characteristics associated with the long-term survival of peritoneal metastases from CRC. We retrospectively analyzed 206 long-term survivors who underwent CRS for peritoneal metastases from CRC. We found that most long-term survivors showed low peritoneal cancer index (PCI), low PCI of small bowel subsets, and complete cytoreduction (CC-0), while some exhibited characteristics considered associated with poor prognosis.

Abstract

Background: We conducted this study to review the patient characteristics associated with long-term survival in patients with peritoneal metastases from colorectal cancer who underwent cytoreductive surgery (CRS). Methods: We retrospectively investigated patients with peritoneal metastases from CRC treated with curative intent surgery with or without hyperthermic intraperitoneal chemotherapy at 13 institutions worldwide between January 1985 and April 2015 and survived longer than five years after the first CRS for peritoneal metastases. Clinical and oncological features and therapeutic parameters were described and analyzed. Results: Two hundred six long-term survivors were available for study. The median peritoneal cancer index (PCI) of this cohort was 4 (interquartile range (IQR), 2–7), and the median score of the small bowel regions of the PCI (SB-PCI) was 0 (IQR, 0–2). Complete cytoreduction (CC-0) was achieved in 180 (87.4%) patients. Recurrence was observed in 122 (59.2%) patients at a median of 1.8 (IQR, 1.2–2.6) years. Conclusions: While most long-term survivors showed low PCI/SB-PCI and CCR-0, some had characteristics considered associated with poor prognosis. Curative intent treatments may be considered in well-informed and fit patients showing negative factors affecting survival outcome.

Construction and validation a nomogram to predict overall survival for colorectal signet ring cell carcinoma

To construct and validate a nomogram to predict the overall survival (OS) of colorectal signet ring cell carcinoma (SRCC). The potentially eligible cases were obtained against the SEER database from 2004 to 2015. Log-rank test and Cox analysis were conducted to identify the independent prognostic factors for predicting OS. The identified prognostic factors were later integrated for the construction of an OS prediction nomogram. Altogether 2904 eligible cases were identified, and the median survival time was 18 (range: 0–155) months. As suggested by multivariate analysis, age, primary site, grade, tumor size, T stage, N stage, M stage, surgery, lymph node dissection and chemotherapy were identified as the independent factors for predicting OS. Afterwards, the above variables were incorporated into the nomogram. The C-index indicated better discriminatory ability of the nomogram than AJCC 8th TNM staging and SEER summary stage systems (both P < 0.001). Calibration plots further showed good consistency between the nomogram prediction and actual observation. The time independent area under the curves (tAUCs) for 3-year and 5-year OS in nomogram were larger than AJCC and SEER summary stage system. The constructed nomogram could potentially predict the survival of colorectal SRCC individuals.

Prospective correlation of the radiological, surgical and pathological findings in patients undergoing cytoreductive surgery for colorectal peritoneal metastases: implications for the preoperative estimation of the peritoneal cancer index

AIM

The peritoneal cancer index (PCI) is one of the strongest prognostic factors in patients undergoing cytoreductive surgery (CRS) for colorectal peritoneal metastases. Using pathological evaluation, however, the disease extent differs in a large proportion of patients. Our aim was to study the correlation between the radiological (rPCI), surgical (sPCI) and pathological (pPCI) PCI in order to determine factors affecting the discordance between these indices and their potential therapeutic implications.

METHOD

From July 2018 to December 2019, 128 patients were included in this study. The radiological, pathological and surgical findings were compared. A protocol for pathological evaluation was followed at all centres.

RESULTS

All patients underwent a CT scan and 102 (79.6%) had a peritoneal MRI. The rPCI was the same as the sPCI in 81 (63.2%) patients and the pPCI in 93 (72.6%). Concordance was significantly lower for moderate-volume (sPCI 13-20) and high-volume (sPCI > 20) disease than for low-volume disease (sPCI 0-12) (P < 0.001 for sPCI; P = 0.001 for pPCI). The accuracy of imaging in predicting presence/absence of disease upon pathological evaluation ranged from 63% to 97% in the different regions of the PCI. The pPCI concurred with the sPCI in 86 (68.8%) patients. Of the nine patients with sPCI > 20, the pPCI was less than 20 in six.

CONCLUSION

The rPCI and sPCI both concurred with pPCI in approximately two thirds of patients. Preoperative evaluation should focus on the range in which the sPCI lies and not its absolute value. Radiological evaluation did not overestimate sPCI in any patient with high/moderate-volume disease. The benefit of CRS in patients with a high r/sPCI (> 20) who respond to systemic therapies should be prospectively evaluated.

Clinical and Radiologic Predictors of a Pathologic Complete Response to Neoadjuvant Chemotherapy (NACT) in Patients Undergoing Cytoreductive Surgery for Colorectal Peritoneal Metastases: Results of a Prospective Multi-center Study

BACKGROUND

Patients undergoing cytoreductive surgery for colorectal peritoneal metastases who have a pathologic complete response (pCR) to neoadjuvant chemotherapy experience a significantly longer survival than those with residual disease. This response is known only after surgery. This study aimed to examine clinical and radiologic predictors of a pCR.

METHODS

From July 2018 to December 2019, the study prospectively enrolled 120 patients. The clinical and radiologic findings were compared between patients with and without a pCR. A protocol for pathologic evaluation was followed.

RESULTS

A pCR was observed in 34 patients (28.3%). Receiver operating characteristic (ROC) curves showed that patients with a surgical Peritoneal Cancer Index (sPCI) of 3 or lower had an 80% probability of experiencing a pCR, and that patients with a radiologic PCI (rPCI) of 2 or lower had a 70% probability of experiencing a pCR. A pCR was correctly predicted for 47% of the patients by imaging and for 44.4% of the patients by surgical evaluation. The site of primary tumor, the timing of peritoneal metastasis (PM), histology, tumor marker positivity, and mutations in known poor prognostic genes (KRAS) did not differ between the patients with and those without pCR. The primary tumor showed residual disease in 23.5% and regional nodes in 26.4% of the patients with pCR.

CONCLUSIONS

The rPCI and sPCI concurred with a pCR in less than 50% of the patients. The patients with a lower PCI had greater concordance. An sPCI of 3 or lower was predictive of a pCR in 80% of the patients. The impact of KRAS mutations on pCR should be evaluated in a larger series. The predictors of pCR and response to systemic chemotherapy should be incorporated in prognostic scores used to select patients for surgery.

Cytoreductive surgery and HIPEC for malignant ascites from colorectal cancer - a randomized study

INTRODUCTION

The efficacy of different timings of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) in controlling malignant ascites caused by peritoneal carcinomatosis of colorectal cancer (CRC) is not well defined. The study aims to investigate the clinical efficacy and safety of different timings of CRS with HIPEC for malignant ascites caused by peritoneal carcinomatosis from CRC.

MATERIALS AND METHODS

This was a preliminary randomized controlled study performed at the Intracelom Hyperthermic Perfusion Therapy Center of the Cancer Hospital of Guangzhou Medical University (China) from December 2008 to December 2016. The patients were randomized to: CRS, followed by HIPEC (CRS+HIPEC; n = 14), and ultrasound-guided HIPEC, followed by CRS 1 to 2 weeks later (HIPEC+ delayed cytoreductive surgery (dCRS) group, n = 14). The endpoints were complete remission rate of ascites, successful complete CRS rate, and overall survival.

RESULTS

Malignant ascites in all patients showed complete remission; the total effective rate was 100%. Complete CRS was not feasible in any patient. The median follow-up of the 2 groups was 41.9 and 42.3 months in the CRS+HIPEC and HIPEC+dCRS groups, respectively. Overall survival was 14.5 (95%CI: 7-19 months) and 14.3 months (95%CI: 4-21 months) (P > .05). The adverse effects of HIPEC were manageable.

CONCLUSIONS

CRS+HIPEC and HIPEC+dCRS have the same efficacy in controlling malignant ascites caused by CRC and peritoneal carcinomatosis. The timing of CRS and HIPEC does not prolong the survival of patients with peritoneal carcinomatosis from CRC, even when a complete CRS is not feasible.

Identification of pharmacogenetic biomarkers for efficacy of cytoreductive surgery plus hyperthermic intraperitoneal mitomycin C in patients with colorectal peritoneal metastases

INTRODUCTION

Mitomycin C (MMC) is commonly used in patients with colorectal peritoneal metastases (CPM) treated with cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (CRS + HIPEC). MMC requires metabolic activation prior to exert its cytotoxic effect of which the main activating enzymes are NQO1 and POR. However, not all patients are able to activate MMC for example due to polymorphisms in the genes encoding these enzymes. The aim of this study was to investigate the association of NQO1∗2, NQO1∗3, and POR∗28 with the efficacy of CRS + HIPEC with MMC in patients with CPM.

METHOD

A retrospective follow-up design was used to study genetic association in patients with histologically proven CPM treated with CRS + HIPEC with MMC with respect to peritoneal recurrence rate after 3 months (primary endpoint), after 6 months, disease-free survival and overall survival. Genetic polymorphisms NQO1∗2, NQO1∗3, and POR∗28 were tested for association.

RESULTS

A total of 253 patients were included. In NQO1∗3 carriers the peritoneal recurrence rate 3 and 6 months after HIPEC was significantly higher than in wild type patients, respectively 30.0% vs 3.8% (p = 0.009) and 40.0% vs 12.1% (p = 0.031). In line with these results, NQO1∗3 was associated with a shorter disease-free survival (HR 2.04, 95% CI [1.03-4.03]). There was no significant association with overall survival (HR 1.42, 95% CI [0.66-3.07]).

CONCLUSION

Carriership of the NQO1∗3 allele is associated with worse peritoneal recurrence rate and disease-free survival. These results suggest that individualization of patients treated with CRS + HIPEC based upon pharmacogenetics may be beneficial.

The Pathologic Peritoneal Cancer Index (PCI) Strongly Differs From the Surgical PCI in Peritoneal Metastases Arising From Various Primary Tumors

BACKGROUND

The surgical peritoneal cancer index (sPCI) is calculated based on a subjective evaluation of the extent of peritoneal disease during surgery. The pathologic PCI (pPCI) may be a more accurate and objective method for determining the PCI. This study aimed to compare the sPCI and pPCI and to study the potential pitfalls and clinical implications of using the pPCI.

METHODS

This prospective study (July to December 2018) included all patients undergoing cytoreductive surgery (CRS). The pPCI was calculated for each patient and compared with the sPCI. The impact of potential confounding factors on the difference between pPCI and sPCI was evaluated.

RESULTS

Among 191 patients undergoing CRS at four centers, the pPCI and sPCI were concordant for 37 patients (19.3%). The pPCI was lower than the sPCI for 125 patients (65.4%) and higher for 29 patients (15.1%). The concordance between the two groups was maximum for gastric cancer (38.8%) and colorectal cancer (27.6%) and least for mesothelioma (6.7%) and rare primary tumors (5.6%) (p = 0.04). The difference was 0 to 3 points for 119 patients (62.3%), 4 to 5 points for 27 patients (14.1%), and more than 5 points for 45 patients (23.5%). The rate of concordance was not influenced by the use of neoadjuvant chemotherapy (NACT) (p = 0.4), but the difference was greater when NACT was used (p = 0.03).

CONCLUSIONS

The pPCI strongly differs from the sPCI for patients undergoing CRS for peritoneal disease and may provide a more accurate evaluation of the peritoneal disease extent. Further studies are needed to determine its prognostic value compared with sPCI, and consensus guidelines are needed for calculating it.

Status of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in patients with peritoneal carcinomatosis from colorectal cancer

Peritoneal carcinomatosis (PC) was previously considered an incurable disease with a poor survival outcome. As our understanding of its biology evolved, the paradigm of the management of PC from colorectal cancer (CRC) has changed, including the combination of macroscopic disease control, cytoreductive surgery (CRS), maximal regional chemotherapy to treat residual microscopic disease, and hyperthermic intraperitoneal chemotherapy (HIPEC). As with many surgical innovations, CRS with HIPEC has evolved faster than data to support it, leaving many skeptics and critics. This review highlights the recent evidence of current practice and outcome of CRS with HIPEC. Furthermore, it also summarizes the ongoing clinical trials and potential future progress of this treatment modality.

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.

P.R.O.P.S. - A novel Pre-Operative Predictive Score for unresectability in patients with colorectal peritoneal metastases being considered for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC)

Background

Twenty to thirty percent of planned cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC) procedures are abandoned intra-operatively. Pre-operative factors associated with unresectability identified previously were used to develop a Pre-Operative Predictive Score (PROPS), which was compared with current selection criteria—Peritoneal Surface Disease Severity Score (PSDSS), Verwaal’s Prognostic Score (PS) and Colorectal Peritoneal Metastases Prognostic Surgical Score (COMPASS), to determine which score provides the best prediction for unresectability.

Methods

Fifty-six patients with peritoneal metastases of colorectal origin were included. Beta-coefficient values of significant variables (p < 0.05) were determined from multivariate analysis to develop PROPS. PROPS, PSDSS, PS and COMPASS were compared using a receiver operating characteristic curve to calculate its accuracy, sensitivity and specificity.

Results

PROPS consisted of nine patient and tumour factors which were categorised into three groups: (i) poor tumour biology: previous inadequate resection, underwent multiple lines of chemotherapy and poorly differentiated or signet cell histology; (ii) heavy tumour burden: abdominal distension, palpable abdominal mass and computed tomography findings of ascites, small bowel disease and/or omental thickening; and (iii) active tumour proliferation: elevated tumour markers. Overall, PROPS achieved 86% accuracy with 100% sensitivity and 68% specificity, PSDSS achieved 85% accuracy with 100% sensitivity and 63% specificity, PS achieved 73% accuracy with 100% sensitivity and 68% specificity and COMPASS achieved 61% accuracy with 27% sensitivity and 100% specificity.

Conclusions

PROPS is more effective in predicting unresectability as compared to PSDSS, PS and COMPASS, and has the added advantage of using solely pre-operative factors.

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.

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.

Cytoreduction plus hyperthermic intraperitoneal chemotherapy for peritoneal carcinomatosis in colorectal cancer patients: a single-center cohort study

Background

In this study, we report our experience of cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) in patients with peritoneal carcinomatosis (PC) from colorectal cancer (CRC), focusing on the factors affecting survival.

Methods

All patients with surgically treated PC from colorectal cancer and with no involvement of other organs referred to our institute from March 2005 to December 2017 were included in the analysis.

Results

Thirty-eight patients underwent CRS-HIPEC, and all had a completeness of cytoreduction score of 0 (CC0). The median operating time was 645 min (interquartile range [IQR] 565–710). Five patients (13.1%) had Clavien-Dindo grade > 2 postoperative complications. Median overall survival (OS) was 60 months. In the Cox regression for OS, calculated on the CRS-HIPEC group, the peritoneal cancer index (PCI) > 6 (hazard ratio [HR] 4.48, IQR 1.68–11.9, P = 0.003) and significant nodal involvement (N2) (HR 3.89, IQR 1.50–10.1, P = 0.005) were independent prognostic factors. Median disease-free survival (DFS) was 16 months. Only N2 (HR 2.44, IQR 1.11–5.36, P = 0.027) was a significantly negative prognostic factor for DFS in multivariate analysis.

Conclusions

CRS-HIPEC can substantially improve survival. However, patients with high PCI (PCI > 6) and significant nodal involvement (N2) may not benefit from the procedure.

Historical perspective: Two decades of progress in treating metastatic colorectal cancer

Colorectal cancer is the third most commonly diagnosed cancer in the United States. While screening methods strive to improve rates of early stage detection, 25% of patients have metastatic disease at the time of diagnosis, with the most common sites being the liver, lung, and peritoneum. While once perceived as hopeless, the last two decades have seen substantial strides in the medical, surgical, and regional therapies to treat metastatic disease offering significant improvements in survival.

Systematic Review of Variations in Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Peritoneal Metastasis from Colorectal Cancer

Background: Cytoreductive surgery (CRS), followed by hyperthermic intraperitoneal chemotherapy (HIPEC), combines radical surgery with abdominal heated chemotherapy, constituting a multimodal treatment approach. Since clear standards for HIPEC conduct in colorectal carcinoma (CRC) are lacking, we aimed to provide a comprehensive structured survey. Data sources and study eligibility criteria: A systematic literature search was performed in PubMed, with keywords “HIPEC” and “colorectal cancer”, according to established guidelines. Articles were systematically screened, selecting 87 publications complemented by 48 publications identified through extended search for subsequent synthesis and evaluation, extracting inter alia details on used drugs, dosage, temperature, exposure times, and carrier solutions. Results: Compiled publications contained 171 reports on HIPEC conduct foremost with mitomycin C and oxaliplatin, but also other drugs and drug combinations, comprising at least 60 different procedures. We hence provide an overview of interconnections between HIPEC protocols, used drugs and carrier solutions as well as their volumes. In addition, HIPEC temperatures and dosing benchmarks, as well as an estimate of in vivo resulting drug concentrations are demonstrated. Conclusions and implications: Owing to recent developments, HIPEC conduct and practices need to be reassessed. Unfortunately, imprecise and lacking reporting is frequent, which is why minimal information requirements should be established for HIPEC and the introduction of final drug concentrations for comparability reasons seems sensible.

The impact of radiological retroperitoneal lymphadenopathy on survival after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for colorectal peritoneal metastases

OBJECTIVES

To investigate the impact of retroperitoneal lymphadenopathy (RPLP) on pre-operative CT scan on overall survival (OS) and disease-free survival (DFS) after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for peritoneal metastases (PM) of colorectal cancer.

BACKGROUND

In patients with PM enlarged retroperitoneal lymph nodes (RPLP) are usually considered extra-regional lymph node metastases and therefore these patients may be excluded from CRS-HIPEC. This is a clinical dilemma since it is often hard to obtain histology from these nodes.

METHODS

In this multicenter, retrospective study all consecutive patients with colorectal PM treated with CRS-HIPEC between 2004 and 2013 were included. The preoperative CT-scan was re-analyzed for the presence of RPLP based on the radiological appearance of enlarged lymph nodes. Outcomes were OS and DFS. Kaplan-Meier methods and Cox regression modeling were used to analyze the impact of RPLP on OS and DFS.

RESULTS

In 25 of 401 patients (6.1%) RPLP was observed on the preoperative CT-scan. Patient, tumor and surgical characteristics did not statistically significantly differ between groups with and without RPLP. After a median follow-up of 46 months, the one-, three- and five-year survival was 80%, 59%, 38% and 90%, 50%, 36% in the group with and without RPLP respectively. Median OS (47 vs. 35 months, logrank: p = 0.70) and median DFS (14 vs. 15 months, logrank: p = 0.81) did not statistically significantly differ between groups. In multivariable analysis, RPLP did not significantly influence survival.

CONCLUSION

Enlarged retroperitoneal lymph nodes on a pre-operative CT-scan should not automatically exclude patients from CRS-HIPEC.

Malignant Bowel Obstruction: Reappraising the Value of Surgery

Urgent palliative surgery in the setting of advanced malignancy is associated with significant morbidity, mortality, and cost. Malignant bowel obstruction is the most frequent indication for such intervention. Traditional surgical dogma is often invoked to justify associated risks and cost, but little evidence exists to support surgical over nonsurgical approaches. Evolving evidence may provide more meaningful guidance for treatment selection.

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.