The importance of integrating diagnostic modalities in patient selection for CRS-HIPEC in colorectal peritoneal metastases

BACKGROUND

Despite thorough preoperative work-up for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), so called open-close (OC) procedures as a result of irresectable disease remain common. Currently, diagnostic laparoscopy (DLS) is considered the gold standard, and consequently overrules the results of computed tomography (CT) scans; however, certain regions of the abdomen are difficult to assess and postoperative adhesion formation may further compromise staging during DLS.

PURPOSE

To determine whether better clinical assessment could be achieved by combining the results of DLS and preoperative CT scans during a multidisciplinary team (MDT) meeting.

MATERIAL AND METHODS

All patients who were eligible for CRS-HIPEC after DLS, but eventually underwent an OC procedure between 2010 and 2018 were selected. Radiological reassessment of CT scans was performed and combined with assessment of the DLS during a MDT meeting. The MDT was blinded for the outcome of the procedure (OC vs. CRS-HIPEC).

RESULTS

The majority of the OC procedures (69%) was correctly predicted by the MDT. In most patients (88%), this conclusion was based on the combination of the radiological and surgical peritoneal cancer index (PCI). CT was particularly accurate for detection of larger tumor deposits in the abdominal regions, as 84%-86% was detected. Assessment of lesions in the small bowel regions is troublesome; 72% of lesions are missed on the preoperative CT scan.

CONCLUSIONS

A combination of radiological and surgical assessment of the PCI may lead to improved preoperative patient selection for CRS-HIPEC.

Comparing patient reported abdominal pain between patients treated with oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy (PIPAC-OX) and primary colorectal cancer surgery

Oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy (PIPAC-OX) is an emerging palliative treatment for patients with unresectable colorectal peritoneal metastases. Previously, our study group reported that patients experienced abdominal pain for several weeks after PIPAC-OX. However, it is unknown how this compares to abdominal pain after regular colorectal cancer surgery. To provide some perspective, this study compared the presence of abdominal pain after PIPAC-OX to the presence of abdominal pain after primary tumor surgery. Patient reported abdominal pain scores (EORTC QLQ-CR-29), from two prospective, Dutch cohorts were used in this study. Scores ranged from 0 to 100, a higher score represents more abdominal pain. Abdominal pain at baseline and at four weeks after treatment were compared between the two groups. Twenty patients who underwent PIPAC-OX and 322 patients who underwent primary tumor surgery were included in the analysis. At baseline, there were no differences in abdominal pain between both groups (mean 20 vs. 18, respectively; p = 0.688). Four weeks after treatment, abdominal pain was significantly worse in the PIPAC group (39 vs 15, respectively; p < 0.001; Cohen's d = 0.99). The differential effect over time for abdominal pain differed significantly between both groups (mean difference: 19 vs - 3, respectively; p = 0.004; Cohen's d = 0.88). PIPAC-OX resulted in significantly worse postoperative abdominal pain than primary tumor surgery. These results can be used for patient counseling and stress the need for adequate analgesia during and after PIPAC-OX. Further research is required to prevent or reduce abdominal pain after PIPAC-OX.Trial registration CRC-PIPAC: Clinicaltrails.gov NCT03246321 (01-10-2017).

Phase I study of intraperitoneal irinotecan combined with palliative systemic chemotherapy in patients with colorectal peritoneal metastases

BACKGROUND

Patients with colorectal peritoneal metastases who are not eligible for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) owing to extensive peritoneal disease have a poor prognosis. It was hypothesized that these patients may benefit from the addition of intraperitoneal irinotecan to standard palliative systemic chemotherapy.

METHODS

This was a classical 3 + 3 phase I dose-escalation trial in patients with colorectal peritoneal metastases who were not eligible for CRS-HIPEC. Intraperitoneal irinotecan was administered every 2 weeks, concomitantly with systemic FOLFOX (5-fluorouracil, folinic acid, oxaliplatin)-bevacizumab. The primary objective was to determine the maximum tolerated dose and dose-limiting toxicities. Secondary objectives were to elucidate the systemic and intraperitoneal pharmacokinetics, safety profile, and efficacy.

RESULTS

Eighteen patients were treated. No dose-limiting toxicities were observed with 50 mg (4 patients) and 75 mg (9 patients) intraperitoneal irinotecan. Two dose-limiting toxicities occurred with 100 mg irinotecan among five patients. The maximum tolerated dose of intraperitoneal irinotecan was established to be 75 mg, and it was well tolerated. Intraperitoneal exposure to SN-38 (active metabolite of irinotecan) was high compared with systemic exposure (median intraperitoneal area under the curve (AUC) to systemic AUC ratio 4.6). Thirteen patients had a partial radiological response and five had stable disease. Four patients showed a complete response during post-treatment diagnostic laparoscopy. Five patients underwent salvage resection or CRS-HIPEC. Median overall survival was 23.9 months.

CONCLUSION

Administration of 75 mg intraperitoneal irinotecan concomitantly with systemic FOLFOX-bevacizumab was safe and well tolerated. Intraperitoneal SN-38 exposure was high and prolonged. As oncological outcomes were promising, intraperitoneal administration of irinotecan may be a good alternative to other, more invasive and costly treatment options. A phase II study is currently accruing.

Insights into synchronous peritoneal metastases from hepatobiliary origin: Incidence, risk factors, treatment, and survival from a nationwide database

INTRODUCTION

- This population-based study aimed to investigate incidence, risk factors, treatment, and survival of synchronous peritoneal metastases (PM) of hepatobiliary origin.

METHODS

- All Dutch patients diagnosed with hepatobiliary cancer between 2009 and 2018 were selected. Factors associated with PM were identified with logistic regression analyses. Treatments for patients with PM were categorized into local therapy, systemic therapy, and best supportive care (BSC). Overall survival (OS) was investigated using log-rank test.

RESULTS

- In total, 12 649 patients were diagnosed with hepatobiliary cancer of whom 8% (n = 1066) were diagnosed with synchronous PM (12% [n = 882/6519] in biliary tract cancer [BTC] vs. 4% [n = 184/5248] in hepatocellular carcinoma [HCC]). Factors that were positively associated with PM were the female sex (OR 1.18, 95% CI 1.03-1.35), BTC (OR 2.93, 95% CI 2.46-3.50), diagnosis in more recent years (2013-2015: OR 1.42, 95% CI 1.20-1.68; 2016-2018: OR 1.48, 95% CI 1.26-1.75), T3/T4 stage (OR 1.84, 95% CI 1.55-2.18), N1/N2 stage (OR 1.31, 95% CI 1.12-1.53) and other synchronous systemic metastases (OR 1.85, 95% CI 1.62-2.12). Of all PM patients, 723 (68%) received BSC only. Median OS was 2.7 months (IQR 0.9-8.2) in PM patients.

CONCLUSION

- Synchronous PM were found in 8% of all hepatobiliary cancer patients and occurred more often in BTC than in HCC. Most patients with PM received BSC only. Given the high incidence and dismal prognosis of PM patients, extended research in hepatobiliary PM is needed to achieve better outcome in these patients.

A propensity score-matched analysis of oncological outcome after systemic therapy for stage IV colorectal cancer: Impact of synchronous ovarian metastases

The reported incidence of synchronous and metachronous ovarian metastases (OM) from colorectal cancer (CRC) is ~3.4%. OM from CRC are often considered sanctuary sites due to their lower sensitivity to systemic treatment. It has thus been hypothesized that the presence of OM decreases overall survival. Therefore, the purpose of our study was to evaluate the impact of synchronous OM on overall survival in female patients with stage IV CRC treated with systemic therapy alone with palliative intent. The present study used data from the Netherlands Cancer Registry and included female CRC patients with synchronous systemic metastases who were treated with systemic therapy between 2008 and 2018. A subsample was created using propensity score matching to create comparable groups. Propensity scores were determined using a logistic regression model in which the dependent variable was the presence of OM and the independent variables were the variables that differed significantly between both groups. Our study included 5253 patients with stage IV CRC that received systemic therapy. Among these patients, 161 (3%) had OM while 5092 (97%) had extra-ovarian metastases only. Three-year overall survival rates did not show a significant difference between patients with OM compared to patients without ovarian metastases. Moreover, the propensity score-matched analysis showed that the presence of OM in patients treated with systemic therapy for stage IV CRC disease was not associated with decreased 3-year overall survival. However, the results of the present study should be interpreted with caution, due to its observational character and used selection criteria.

Perioperative Systemic Therapy Versus Cytoreductive Surgery and HIPEC Alone for Resectable Colorectal Peritoneal Metastases: Patient-Reported Outcomes of a Randomized Phase II Trial

BACKGROUND

As part of a randomized phase II trial in patients with isolated resectable colorectal peritoneal metastases (CPMs), the present study compared patient-reported outcomes (PROs) of patients treated with perioperative systemic therapy versus cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) alone. Also, PROs of patients receiving perioperative systemic therapy were explored.

PATIENTS AND METHODS

Eligible patients were randomized to perioperative systemic therapy (experimental) or CRS-HIPEC alone (control). PROs were assessed using EORTC QLQ-C30, QLQ-CR29, and EQ-5D-5L questionnaires at baseline, after neoadjuvant treatment (experimental), and at 3 and 6 months postoperatively. Linear mixed modeling was used to compare five predefined PROs (visual analog scale, global health status, physical functioning, fatigue, C30 summary score) between arms and to longitudinally analyze PROs in the experimental arm.

RESULTS

Of 79 analyzed patients, 37 (47%) received perioperative systemic therapy. All predefined PROs were comparable between arms at all timepoints and returned to baseline at 3 or 6 months postoperatively. The experimental arm had worsening of fatigue [mean difference (MD) + 14, p = 0.001], loss of appetite (MD + 15, p = 0.003), hair loss (MD + 18, p < 0.001), and loss of taste (MD + 27, p < 0.001) after neoadjuvant treatment. Except for loss of appetite, these PROs returned to baseline at 3 or 6 months postoperatively.

CONCLUSIONS

In patients with resectable CPM randomized to perioperative systemic therapy or CRS-HIPEC alone, PROs were comparable between arms and returned to baseline postoperatively. Together with the trial's previously reported feasibility and safety data, these findings show acceptable tolerability of perioperative systemic therapy in this setting.

The Impact of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS-HIPEC) versus Conventional Surgery on Patient-Reported Outcomes: A Comparative Cohort Study between the CAIRO6 Trial and the PROCORE Study

Purpose-To compare patient-reported outcomes (PROs) of patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for colorectal peritoneal metastases to PROs of colorectal cancer (CRC) patients undergoing conventional surgery. Methods-Data were extracted from the CAIRO6 trial (CRS-HIPEC group) and the PROCORE study (conventional surgery group). Nine predefined PROs (derived from the EORTC QLQ-C30 questionnaire) were compared at baseline, in the early postoperative period and one year postoperatively, with correction for treatment with systemic therapy using linear mixed modeling. Results-In total, 331 patients were included: 71 in the CRS-HIPEC group and 260 in the conventional surgery group. All predefined PROs (fatigue, diarrhea, C30 summary score, Global Health Status, physical, role, emotional, cognitive, and social functioning) did not differ significantly between the groups at all three timepoints, and differential effects over time for all PROs did not differ significantly between the groups. Significant worsening of fatigue, C30 summary score, physical and role functioning (both groups), and cognitive and social functioning (conventional surgery group only) was present in the early postoperative period. All scores returned to baseline at one year postoperatively, except for physical and cognitive functioning in the conventional surgery group. Emotional functioning improved postoperatively in both groups compared to baseline. Conclusion-Despite a more extensive procedure with greater risk of morbidity, CRS-HIPEC in patients with colorectal peritoneal metastases did not have a greater negative impact on PROs than conventional surgery in patients with CRC. Further, systemic therapy did not affect these PROs. These findings may facilitate future patient counseling and shared decision making in clinical practice.

The impact of an open or laparoscopic approach on the development of metachronous peritoneal metastases after primary resection of colorectal cancer: results from a population-based cohort study

BACKGROUND

This study aimed to assess the impact of open or laparoscopic resection of primary colorectal cancer (CRC) on the development of metachronous colorectal peritoneal metastases (CPM) in a population-based cohort.

MATERIALS AND METHODS

This was a retrospective, population-based study of CRC patients who underwent open or laparoscopic resection of the primary tumour in the Netherlands between January 1st and June 30th 2015. Patients with synchronous metastases were excluded. CPM were considered metachronous if diagnosed ≥ 90 days after resection of primary CRC. Multivariable cox regression analysis was performed to correct for tumour location, histology, differentiation, and stage, nodal stage, tumour perforation, primary surgery type, and unclear resection margins.

RESULTS

In total, 1516 CRC patients underwent open resection and 3236 CRC patients underwent laparoscopic resection, with a 3-year cumulative incidence of metachronous CPM of 7.3% and 3.7%, respectively (p < 0.001), after median follow-up of 42 months. Open surgical approach was significantly associated with the development of metachronous CPM: HR 1.4 [95%CI 1.1-1.8]. Other prognostic factors were mucinous adenocarcinoma histology (HR 1.6, 95%CI 1.0-2.5), T4 stage (HR 3.2, 95%CI 2.3-4.5), N1 stage (HR 2.9, 95%CI 2.1-4.0), and N2 stage (HR 4.2, 95%CI 2.9-6.1).

CONCLUSIONS

Patients treated with open resection had a significantly higher risk to develop metachronous CPM than patients treated with laparoscopic resection. The mechanisms underlying this phenomenon remain unknown but might be related to differences in per-operative specimen handling, tumour spill, surgical trauma and pro-inflammatory response. This finding might imply the need for a personalized follow-up after primary resection of CRC.

Patient-reported outcomes during repetitive oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy for isolated unresectable colorectal peritoneal metastases in a multicenter, single-arm, phase 2 trial (CRC-PIPAC)

BACKGROUND

CRC-PIPAC prospectively assessed repetitive oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy (PIPAC-OX) as a palliative monotherapy (i.e., without concomitant systemic therapy in between subsequent procedures) for unresectable colorectal peritoneal metastases (CPM). The present study explored patient-reported outcomes (PROs) during trial treatment.

METHODS

In this single-arm phase 2 trial in two tertiary centers, patients with isolated unresectable CPM received 6-weekly PIPAC-OX (92 mg/m²). PROs (calculated from EQ-5D-5L, and EORTC QLQ-C30 and QLQ-CR29) were compared between baseline and 1 and 4 weeks after the first three procedures using linear mixed modeling with determination of clinical relevance (Cohen's D ≥ 0.50) of statistically significant differences.

RESULTS

Twenty patients underwent 59 procedures (median 3 [range 1-6]). Several PROs solely worsened 1 week after the first procedure (index value - 0.10, p < 0.001; physical functioning - 20, p < 0.001; role functioning - 27, p < 0.001; social functioning - 18, p < 0.001; C30 summary score - 16, p < 0.001; appetite loss + 15, p = 0.007; diarrhea + 15, p = 0.002; urinary frequency + 13, p = 0.004; flatulence + 13, p = 0.001). These PROs returned to baseline at subsequent time points. Other PROs worsened 1 week after the first procedure (fatigue + 23, p < 0.001; pain + 29, p < 0.001; abdominal pain + 32, p < 0.001), second procedure (fatigue + 20, p < 0.001; pain + 21, p < 0.001; abdominal pain + 20, p = 0.002), and third procedure (pain + 22, p < 0.001; abdominal pain + 22, p = 0.002). Except for appetite loss, all changes were clinically relevant. All analyzed PROs returned to baseline 4 weeks after the third procedure.

CONCLUSIONS

Patients receiving repetitive PIPAC-OX monotherapy for unresectable CPM had clinically relevant but reversible worsening of several PROs, mainly 1 week after the first procedure.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT03246321; Netherlands trial register: NL6426.

Treatment Strategies and Prognosis of Patients With Synchronous or Metachronous Colorectal Peritoneal Metastases: A Population-Based Study

BACKGROUND

This study aimed to compare treatment strategies and survival of patients with synchronous colorectal peritoneal metastases (CPM) and patients with metachronous CPM in a nationwide cohort.

METHODS

All patients from the Netherlands Cancer Registry with synchronous or metachronous CPM whose primary colorectal cancer (CRC) was diagnosed between 1 January and 30 June 2015 were included in the study. Treatments were categorized as (A) cytoreductive surgery and hyperthermic intraperitoneal chemotherapy [CRS-HIPEC]; (B) palliative treatment; or (C) best supportive care. Overall survival (OS) for all the patients and disease-free survival (DFS) for those who underwent CRS-HIPEC were compared between the two groups.

RESULTS

Of 7233 patients, 743 had a diagnosis of CPM, including 409 patients with synchronous CPM and 334 patients with metachronous CPM. The median OS was 8.1 months for the patients with synchronous CPM versus 12 months for the patients with metachronous CPM (p = 0.003). After multivariable correction, OS no longer differed between the patients with synchronous CPM and those with metachronous CPM (HR 1.03 [0.83-1.27]). The patients with metachronous CPM more often underwent CRS-HIPEC than the patients with synchronous CPM (16 % vs 8 %; p = 0.001). The two groups did not differ statistically in terms of DFS and OS (median DFS, 21.5 vs 14.1 months, respectively; p = 0.094; median OS, 37.8 vs. 35.8 months, respectively; p = 0.553).

CONCLUSION

This population-based study showed that survival for the patients with synchronous CPM and patients with metachronous CPM did not significantly differ. This suggests that a similar prognosis may be expected for patients selected for treatment regardless of the onset of CPM.

Ovarian metastases from colorectal cancer in young women: a systematic review of the literature

BACKGROUND AND PURPOSE

In female colorectal cancer patients, a mean proportion of synchronous and/or metachronous ovarian metastases of 3.4% was described. Previous literature showed that young or premenopausal women (≤ 55 years of age) may be more frequently affected. Once ovarian metastases are diagnosed, the prognosis of the patient is generally dismal, with 5-year survival varying from 12 to 27%. The present study is aimed at determining the proportion of young or premenopausal women diagnosed with colorectal cancer who presented with or developed ovarian metastases by reviewing the current literature on this topic.

METHODS

This review was performed by querying MEDLINE and EMBASE databases using a combination of terms: "colorectal neoplasms, colorectal cancer, ovarian neoplasms, Krukenberg tumor, young adult, young age, premenopause." Studies that indicated ovarian metastases, either synchronous or metachronous (or a combination of the two), in young women were retrieved and analyzed.

RESULTS

The review identified 14 studies encompassing 3379 young or premenopausal female colorectal cancer patients. In this selected group of patients, a mean proportion of ovarian metastases of 4.6% [95% CI: 4.0;5.4] was found.

CONCLUSIONS

This review showed that approximately one in twenty young female colorectal cancer patients will present with or develop ovarian metastases. Since outcome of this specific oncological pathology is often dismal, this finding is clinically relevant. It demonstrates the need to develop strategies to lower the incidence of ovarian metastases with adequate treatment and counseling of these patients.

Incidence, Treatment, and Survival of Synchronous Peritoneal Metastases in Pancreatic Cancer: Update of a Nationwide Cohort

OBJECTIVE

The aim of the study was to gain insight in the incidence, treatment, and survival of patients with synchronous pancreatic peritoneal metastases.

METHODS

All patients diagnosed with pancreatic cancer between 2008 and 2018 in the Netherlands Cancer Registry were evaluated. The patients were subcategorized as (1) synchronous peritoneal metastases, (2) synchronous systemic metastases, and (3) no metastases.

RESULTS

In total, 25,334 patients with pancreatic cancer were included. Among them, 3524 (14%) presented with synchronous peritoneal metastases, 10,659 (42%) with systemic metastases, and 11,151 (44%) without metastases at the time of diagnosis. The proportion of the patients diagnosed with peritoneal metastases increased over time (11%, 2008; 16%, 2018; P < 0.001). Of these patients, 964 (27%) received cancer treatment and 2560 (73%) received best supportive care. The median overall survival in patients with peritoneal metastases, systemic metastases, and without metastases was 1.9, 2.4, and 8.0 months, respectively (P < 0.001). In the patients with peritoneal metastases, the median overall survival was 5.0 months when undergoing cancer treatment and 1.3 months with best supportive care (P < 0.001).

CONCLUSIONS

Patients with pancreatic cancer are increasingly diagnosed with synchronous peritoneal metastases. Given the current dismal prognosis, research to improve treatment is designated for this patient category.

Synchronous peritoneal metastases from lung cancer: incidence, associated factors, treatment and survival: a Dutch population-based study

Peritoneal metastases (PM) from lung cancer are rare and it is unknown how they affect the prognosis of patients with lung cancer. This population-based study aimed to assess the incidence, associated factors, treatment and prognosis of PM from lung cancer. Data from the Netherlands Cancer Registry were used. All patients diagnosed with lung cancer between 2008 and 2018 were included. Logistic regression analysis was performed to identify factors associated with the presence of PM. Cox regression analysis was performed to identify factors associated with the overall survival (OS) of patients with PM. Between 2008 and 2018, 129,651 patients were diagnosed with lung cancer, of whom 2533 (2.0%) patients were diagnosed with PM. The European Standardized Rate of PM increased significantly from 0.6 in 2008 to 1.4 in 2018 (p < 0.001). Age between 50 and 74 years, T3-4 tumour stage, N2-3 nodal stage, tumour morphology of a small cell lung cancer or adenocarcinoma, and the presence of systemic metastases were associated with the presence of PM. The median OS of patients with PM was 2.5 months. Older age, male sex, T3-4 tumour stage, N2-3 nodal stage, not receiving systemic treatment, and the presence of systemic metastases were associated with a worse OS. Synchronous PM were diagnosed in 2.0% of patients with lung cancer and resulted in a very poor survival.

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

Importance

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

Objective

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

Design, Setting, and Participants

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

Interventions

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

Main Outcomes and Measures

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

Results

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

Conclusions and Relevance

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

Trial Registration

ClinicalTrials.gov Identifier: NCT02758951.

Systemic therapy in addition to cytoreduction and hyperthermic intraperitoneal chemotherapy for colorectal peritoneal metastases: recent insights from clinical studies and translational research

There is a lack of randomized or high-quality intention-to-treat cohort studies addressing the role of systemic therapy in addition to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) as part of the treatment of colorectal peritoneal metastases (PM). Therefore, the choice whether or not to treat patients with systemic therapy is currently mainly based on expert opinion. As a result, treatment with neoadjuvant and/or adjuvant systemic therapy is implemented in various ways around the world. The aim of this review was to provide an overview of recent insights with regard to the systemic treatment of PM of colorectal origin obtained from clinical studies and translational research.

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

Importance

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

Objective

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

Design, Setting, and Participants

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

Exposures

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

Main Outcomes and Measures

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

Results

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

Conclusions and Relevance

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

Comparison of the Peritoneal Cancer Index and Dutch region count as tools to stage patients with peritoneal metastases of colorectal cancer

BACKGROUND

Extent of peritoneal metastases (PM) is among the most powerful prognostic factors for survival after cytoreductive surgery (CRS). This study aimed to compare the Peritoneal Cancer Index (PCI) and the Dutch region count as tools for staging PM of colorectal cancer. The Dutch region count is a simpler classification that distinguishes seven rather than 13 abdominal regions. Presence or absence of PM is recorded.

METHODS

This was a retrospective cohort study in two tertiary referral centres in the Netherlands. Consecutive patients with colorectal PM who were intentionally treated with CRS and subsequent hyperthermic intraperitoneal chemotherapy in 2016 and 2017 were included. The PCI and Dutch region count were both recorded during laparotomy. Correlation between scoring tools was calculated using Spearman's rank correlation coefficient. Diagnostic values were calculated for different cut-off values of the PCI, alongside the Dutch region count. The correlation of both scores was determined for the exploration and validation cohorts separately.

RESULTS

In the exploration and validation cohorts, 73 and 85 patients respectively were included. Spearman's correlation coefficients of 0·897 and 0·961 were observed for continuous scores of the Dutch region count and PCI in the exploration and validation group respectively. A cut-off value of 20 for the PCI score and 5 for the Dutch region count showed 91·9 and 94·5 per cent sensitivity, and 81·8 and 91·7 per cent specificity, respectively.

CONCLUSION

The Dutch region count correlated well with the PCI score, and may help to simplify reporting of the extent of peritoneal disease.

Long-term survival after hyperthermic intraperitoneal chemotherapy using mitomycin C or oxaliplatin in colorectal cancer patients with synchronous peritoneal metastases: A nationwide comparative study

OBJECTIVES

In the Netherlands, limited variability exists in performance of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) among centers treating colorectal peritoneal metastases (PM), except for the intraperitoneal drug administration. This offers a unique opportunity to investigate any disparities in survival between the two most frequently used HIPEC regimens worldwide: mitomycin C (MMC) and oxaliplatin.

METHODS

This was a comparative, population-based cohort study of all Dutch patients diagnosed with synchronous colorectal PM who underwent CRS-HIPEC between 2014 and 2017. They were retrieved from the Netherlands Cancer Registry. Main outcome was overall survival (OS). The effect of the intraperitoneal drug on OS was investigated using multivariable Cox regression analysis.

RESULTS

In total, 297 patients treated between 2014 and 2017 were included. Among them, 177 (59.6%) received MMC and 120 (40.4%) received oxaliplatin. Only primary tumor location was different between the two groups: more left-sided colon in the Oxaliplatin group (47.5% vs. 33.3%, respectively, p=0.048). The 1-, 2- and 3-year OS were 84.6% vs. 85.8%, 61.6% vs. 63.9% and 44.7% vs. 53.5% in patients treated with MMC and oxaliplatin, respectively. Median OS was 30.7 months in the MMC group vs. 46.6 months in the oxaliplatin group (p=0.181). In multivariable analysis, no influence of intraperitoneal drug on survival was observed (adjusted HR 0.77 [0.53-1.13]).

CONCLUSIONS

Long-term survival between patients treated with either MMC or oxaliplatin during CRS-HIPEC was not significantly different.

Concomitant intraperitoneal and systemic chemotherapy for extensive peritoneal metastases of colorectal origin: protocol of the multicentre, open-label, phase I, dose-escalation INTERACT trial

INTRODUCTION

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) has become standard of care for patients with peritoneal metastases of colorectal origin with a low/moderate abdominal disease load. In case of a peritoneal cancer index (PCI) score >20, CRS-HIPEC is not considered to be beneficial. Patients with a PCI >20 are currently offered palliative systemic chemotherapy. Previous studies have shown that systemic chemotherapy is less effective against peritoneal metastases than it is against haematogenous spread of colorectal cancer. It is suggested that patients with peritoneal metastases may benefit from the addition of intraperitoneal chemotherapy to systemic chemotherapy. Aim of this study is to establish the maximum tolerated dose of intraperitoneal irinotecan, added to standard of care systemic therapy for colorectal cancer. Secondary endpoints are to determine the safety and feasibility of this treatment and to establish the pharmacokinetic profile of intraperitoneally administered irinotecan.

METHODS AND ANALYSIS

This phase I, '3+3' dose-escalation, study is performed in two Dutch tertiary referral centres. The study population consists of adult patients with extensive peritoneal metastases of colorectal origin who have a good performance status and no extra-abdominal metastases. According to standard work-up for CRS-HIPEC, patients will undergo a diagnostic laparoscopy to score the PCI. In case of a PCI >20, a peritoneal access port will be placed in the abdomen of the patient. Through this port we will administer intraperitoneal irinotecan, in combination with standard systemic treatment consisting of 5-fluorouracil/leucovorin with oxaliplatin and the targeted agent bevacizumab. Therapy consists of a maximum of 12 cycles 2-weekly.

ETHICS AND DISSEMINATION

This study protocol is approved by a research medical ethics committee (Rotterdam, Netherlands) and the Dutch Competent Authority (CCMO, The Hague, Netherlands). The results of this trial will be submitted for publication in a peer-reviewed scientific journal.

TRAIL REGISTRATION NUMBER

NL6988 and NL2018-000479-33; Pre-results.

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

Background

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

Methods

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

Discussion

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

Trial registration

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