Histological subtype and systemic metastases strongly influence treatment and survival in patients with synchronous colorectal peritoneal metastases

Combined peritoneal and liver metastases in colorectal cancer: A Dutch nationwide population-based analysis of incidence, treatment and survival

INTRODUCTION

The aim of this study was to determine the incidence, treatment patterns, survival and factors associated with curative treatment in colorectal cancer patients with combined liver and peritoneal metastases using Dutch population-based data.

MATERIALS AND METHODS

Data from the Netherlands Cancer Registry were used. All patients diagnosed with synchronous isolated peritoneal and liver metastasized colorectal adenocarcinoma between January 1, 2015 and December 31, 2021 were included. Multivariable regression analyses were performed to identify factors associated with receiving curative treatment. Survival rates were calculated for patients undergoing palliative and curative treatment separately.

RESULTS

Of 14627 patients with colorectal adenocarcinoma in the study period, 927 patients (6.3 %) had isolated liver and peritoneal metastases and were evaluated in this study. Mean age was 66.9 years, non-mucinous and non-signet-ring cell adenocarcinomas were most prevalent (89.0 %) and tumors were mostly located in the colon (92.1 %). Patients were treated with best supportive care (n = 254, 27,4 %), palliative treatment (n = 618, 66,7 %) or curative treatment (n = 55, 5,9 %). Median OS was 1.5 months, 11.3 months, and 32.6 months, respectively. Multivariable analysis showed that younger age (OR 0.95, p < 0.001) and up to 3 liver metastases (OR 0.13, p < 0.001) are positively associated with receiving curative treatment.

CONCLUSION

This population-based study provides a comprehensive overview of the incidence and treatment of patients with synchronous colorectal liver and peritoneal metastases. It shows that in a highly selected group of patients, curative treatment is associated with better overall survival.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Systematic review of risk factors, prognosis, and management of colorectal signet-ring cell carcinoma

BACKGROUND

Colorectal signet-ring cell carcinoma (CSRCC) is a rare clinical entity which accounts for approximately 1% of all colorectal cancers. Although multiple studies concerning this specific topic have been published in the past decades, the pathogenesis, associated risk factors, and potential implications on treatment are still poorly understood. Besides the low incidence, historically confusing histological criteria have resulted in confusing data. Nevertheless, the rising incidence of CSRCC along with relatively young age at presentation and associated dismal prognosis, highlight the actual interest to synthesize the known literature regarding CSRCC.

AIM

To provide an updated overview of risk factors, prognosis, and management of CSRCC.

METHODS

A literature search in the MEDLINE/PubMed database was conducted with the following search terms used: 'Signet ring cell carcinoma' and 'colorectal'. Studies in English language, published after January 1980, were included. Studies included in the qualitative synthesis were evaluated for content concerning epidemiology, risk factors, and clinical, diagnostic, histological, and molecular features, as well as metastatic pattern and therapeutic management. If possible, presented data was extracted in order to present a more detailed overview of the literature.

RESULTS

In total, 67 articles were included for qualitative analysis, of which 54 were eligible for detailed data extraction. CSRCC has a reported incidence between 0.1%-2.4% and frequently presents with advanced disease stage at the time of diagnosis. CSRCC is associated with an impaired overall survival (5-year OS: 0%-46%) and a worse stage-corrected outcome compared to mucinous and not otherwise specified adenocarcinoma. The systematic use of exploratory laparoscopy to determine the presence of peritoneal metastases has been advised. Surgery is the mainstay of treatment, although the rates of curative resection in CSRCC (21%-82%) are lower compared to those in other histological types. In case of peritoneal metastasis, cytoreductive surgery with hyperthermic intraperitoneal chemotherapy should only be proposed in selected patients.

CONCLUSION

CSRCC is a rare clinical entity most often characterized by young age and advanced disease at presentation. As such, diagnostic modalities and therapeutic approach should be tailored accordingly.

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.

Synchronous liver and peritoneal metastases from colorectal cancer: Is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy combined with liver resection a feasible option?

BACKGROUND

Traditionally, synchronous liver resection (LR), cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy for colorectal liver and peritoneal metastases have been contraindicated. Nowadays, clinical practice has promoted this aggressive treatment in selected cases. This study aimed to review surgical and survival results of an extensive surgical approach including CRS with hyperthermic intraperitoneal chemotherapy (HIPEC) and LR.

METHODS

PubMed, EMBASE, and Web of Science databases were matched to find the available literature on this topic. The search period was limited to 10 years (January 2010-January 2021). A threshold of case series of 10 patients or more was applied.

RESULTS

In the search period, out of 114 studies found about liver and peritoneal metastases from colorectal cancer, we found 18 papers matching the inclusion criteria. Higher morbidity and mortality were reported for patients who underwent such an extensive surgical approach when compared with patients who underwent only cytoreductive surgery and HIPEC. Also, survival rates seem worse in the former than in the latter.

CONCLUSION

The role of combined surgical strategy in patients with synchronous liver and peritoneal metastases from colorectal cancer remains controversial. Survival rates and morbidity and mortality seem not in favor of this option. A more accurate selection of patients and more restrictive surgical indications could perhaps help improve results in this subgroup of patients with limited curative options.

Comprehensive Treatment Algorithms of the Swiss Peritoneal Cancer Group for Peritoneal Cancer of Gastrointestinal Origin

Peritoneal cancer (PC) is a dire finding, yet in selected patients, long-term survival is possible. Complete cytoreductive surgery (CRS) together with combination immunochemotherapy is essential to achieve cure. Hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC) are increasingly added to the multimodal treatment. The Swiss Peritoneal Cancer Group (SPCG) is an interdisciplinary group of expert clinicians. It has developed comprehensive treatment algorithms for patients with PC from pseudomyxoma peritonei, peritoneal mesothelioma, gastric, and colorectal origin. They include multimodal neoadjuvant treatment, surgical resection, and palliative care. The indication for and results of CRS HIPEC and PIPAC are discussed in light of the current literature. Institutional volume and clinical expertise required to achieve best outcomes are underlined, while inclusion of patients considered for CRS HIPEC and PIPAC in a clinical registry is strongly advised. The present recommendations are in line with current international guidelines and provide the first comprehensive treatment proposal for patients with PC including intraperitoneal chemotherapy. The SPCG comprehensive treatment algorithms provide evidence-based guidance for the multimodal care of patients with PC of gastrointestinal origin that were endorsed by all Swiss clinicians routinely involved in the multimodal care of these challenging patients.

Effect of hyperthermic intraperitoneal chemotherapy in combination with cytoreductive surgery on the prognosis of patients with colorectal cancer peritoneal metastasis: a systematic review and meta-analysis

Background

Peritoneal metastasis often occurs in patients with colorectal cancer peritoneal metastasis, and the prognosis is poor. A large body of evidence highlights the beneficial effects of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) on survival, but to date, there is little consensus on the optimal treatment strategy for patients with colorectal cancer peritoneal metastasis. The purpose of this study is to evaluate the impact of CRS + HIPEC on survival and provide reference for the treatment of patients with colorectal cancer peritoneal metastasis.

Methods

This systematic review and meta-analysis is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The PubMed, Embase, Cochrane, Web of Knowledge, and ClinicalTrials.gov databases were screened from inception of the review to March 11, 2022. Ten studies were included in qualitative and quantitative analysis.

Results

A total of 3200 patients were enrolled in the study, including 788 patients in the CRS and HIPEC groups and 2412 patients in the control group, of which 3 were randomized controlled trials and 7 were cohort studies. The 3 randomized controlled studies were of high quality, and the quality scores of the 7 cohort studies were all 7 or above, indicating high quality. The results showed that the OS of CRS + HIPEC group was higher than that of control group (HR: 0.53, 95% CI: 0.38–0.73; P < 0.00001, I² = 82.9%); the heterogeneity of the studies was large. The subgroup analysis showed that the OS of CRS and HIPEC group was higher than that of PC group (HR: 0.37, 95% CI: 0.30–0.47; P = 0.215, I² = 31%) and higher than that in CRS group (HR: 0.73, 95% CI: 0.49–1.07; P = 0.163, I² = 44.8%); the heterogeneity of the studies was low. In the OPEN group, the OS of THE CRS and HIPEC groups was higher than that in the control group (HR: 0.51, 95% CI: 0.38–0.70; P = 0.353, I² = 3.9%); OPEN group showed lower heterogeneity. The OS of 60–100-min group was higher than that in the control group (HR: 0.65, 95% CI: 0.49–0.88; P = 0.172, I² = 37.4%); the heterogeneity of the studies was low. Sensitivity analysis showed that there was no significant difference in the results of the combined analysis after each study was deleted. The results of publication bias showed that the P-value of Egger and Begg tests was 0.078 > 0.05, indicating that there is no publication bias.

Conclusions

CRS + HIPEC can improve the survival rate of patients with colorectal cancer peritoneal metastasis

Microsatellite and RAS/RAF Mutational Status as Prognostic Factors in Colorectal Peritoneal Metastases Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) leads to prolonged survival for selected patients with colorectal (CRC) peritoneal metastases (PM). This study aimed to analyze the prognostic role of micro-satellite (MS) status and RAS/RAF mutations for patients treated with CRS.

METHODS

Data were collected from 13 Italian centers with PM expertise within a collaborative group of the Italian Society of Surgical Oncology. Clinical and pathologic variables and KRAS/NRAS/BRAF mutational and MS status were correlated with overall survival (OS) and disease-free survival (DFS).

RESULTS

The study enrolled 437 patients treated with CRS-HIPEC. The median OS was 42.3 months [95% confidence interval (CI), 33.4-51.2 months], and the median DFS was 13.6 months (95% CI, 12.3-14.9 months). The local (peritoneal) DFS was 20.5 months (95% CI, 16.4-24.6 months). In addition to the known clinical factors, KRAS mutations (p = 0.005), BRAF mutations (p = 0.01), and MS status (p = 0.04) were related to survival. The KRAS- and BRAF-mutated patients had a shorter survival than the wild-type (WT) patients (5-year OS, 29.4% and 26.8% vs 51.5%, respectively). The patients with micro-satellite instability (MSI) had a longer survival than the patients with micro-satellite stability (MSS) (5-year OS, 58.3% vs 36.7%). The MSI/WT patients had the best prognosis. The MSS/WT and MSI/mutated patients had similar survivals, whereas the MSS/mutated patients showed the worst prognosis (5-year OS, 70.6%, 48.1%, 23.4%; p = 0.0001). In the multivariable analysis, OS was related to the Peritoneal Cancer Index [hazard ratio (HR), 1.05 per point], completeness of cytoreduction (CC) score (HR, 2.8), N status (HR, 1.6), signet-ring (HR, 2.4), MSI/WT (HR, 0.5), and MSS/WT-MSI/mutation (HR, 0.4). Similar results were obtained for DFS.

CONCLUSION

For patients affected by CRC-PM who are eligible for CRS, clinical and pathologic criteria need to be integrated with molecular features (KRAS/BRAF mutation). Micro-satellite status should be strongly considered because MSI confers a survival advantage over MSS, even for mutated patients.

Outcomes of Combined Peritoneal and Local Treatment for Patients with Peritoneal and Limited Liver Metastases of Colorectal Origin: A Systematic Review and Meta-Analysis

Background

Almost half of all colorectal cancer (CRC) patients will experience metastases at some point, and in the majority of cases, multiple organs will be involved. If the peritoneum is involved in addition to the liver, the current guideline-driven treatment options are limited. The reported overall survival ranges from 6 to 13 months for the current standard of care (systemic treatment). This study aimed to evaluate morbidity and clinical long-term outcomes from a combined local treatment of hepatic metastases with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) used to treat peritoneal metastases.

Methods

A systematic search was performed in PubMed, Embase.com, Web of Science, and Cochrane. Studies evaluating the clinicopathologic data of patients who had both peritoneal and hepatic metastases treated with CRS-HIPEC were included provided sufficient data on the primary outcomes (overall and disease-free survival) were presented. The quality of included studies was assessed using the Methodological Index for Non-Randomized Studies (MINORS).

Results

Patients treated for peritoneal and liver metastases (PMLM group) had a pooled mean survival of 26.4 months (95% confidence interval [CI] 22.4–30.4 months), with a 3-year survival rate of 34% (95% CI 26.7–42.0%) and a 5-year survival rate of 25% (95% CI 17.3–33.8%). Surgical complications occurred more frequently for these patients than for those with peritoneal metastasis only (40% vs 22%; p = 0.0014), but the mortality and reoperation rates did not differ significantly.

Conclusion

This systematic review showed that CRS and HIPEC combined with local treatment of limited liver metastasis for selected patients is feasible, although with increased morbidity and an association with a long-term survival rate of 25%, which is unlikely to be achievable with systemic treatment only.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-10925-y.

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.

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.

Patients with colorectal peritoneal metastases and high peritoneal cancer index may benefit from cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND

Peritoneal cancer index (PCI) >20 is often seen as a contraindication for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with peritoneal metastases (PM) from colorectal cancer. The aim of this study was to compare the overall survival in colorectal PM patients with PCI >20 and PCI ≤20 treated with CRS and HIPEC to those having open-close/debulking procedure only.

METHODS

All patients with colorectal PM and intention to treat with CRS and HIPEC in Uppsala Sweden 2004-2017 were included. Patients scheduled for CRS and HIPEC were divided into three groups, PCI >20, PCI ≤20, and those not operated with CRS and HIPEC stated as open-close including those treated with palliative debulking.

RESULTS

Of 201 operations, 112 (56%) resulted in CRS and HIPEC with PCI ≤20, 45 (22%) in CRS and HIPEC with PCI >20 and 44 (22%) resulted in open-close/debulking. Median survival for CRS and HIPEC and PCI >20 was 20 months (95%CI 14-27 months) with 7% surviving longer than 5 years (n = 3). For CRS and HIPEC and PCI ≤20 the median survival was 33 months (95%CI 30-39 months) with 23% (n = 26) surviving >5years. The median survival for open-close was 9 months (95%CI 4-10 months), no one survived >5years.

CONCLUSION

Patients with PM from colorectal cancer and PCI >20 that were treated with CRS and HIPEC experience a one year longer and doubled overall survival compared with open-close/debulking patients. In addition to PCI, more factors should be taken into account when a decision about proceeding with CRS or not is taken.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

Meta-analysis of prognostic factors for patients with colorectal peritoneal metastasis undergoing cytoreductive surgery and heated intraperitoneal chemotherapy

Background

Up to 15 per cent of colorectal cancers present with peritoneal metastases (CPM). Cytoreductive surgery and heated intraperitoneal chemotherapy (CRS + HIPEC) aims to achieve macroscopic tumour resection combined with HIPEC to destroy microscopic disease. CRS + HIPEC is a major operation with significant morbidity and effects on quality of life (QoL). Improving patient selection is crucial to maximize patient outcomes while minimizing morbidity and mortality. The aim of this study was to identify prognostic factors for patients with CPM undergoing CRS + HIPEC.

Methods

A systematic search of MEDLINE, Embase and Cochrane Library electronic databases was performed using terms for colorectal cancer, peritoneal metastasis and CRS + HIPEC. Included studies focused on the impact of prognostic factors on overall survival following CRS + HIPEC in patients with CPM.

Results

Twenty-four studies described 3128 patients. Obstruction or perforation of the primary tumour (hazard ratio (HR) 2·91, 95 per cent c.i. 1·5 to 5·65), extent of peritoneal metastasis as described by the Peritoneal Carcinomatosis Index (PCI) (per increase of 1 PCI point: HR 1·07, 1·02 to 1·12) and the completeness of cytoreduction (CC score above zero: HR 1·75, 1·18 to 2·59) were associated with reduced overall survival after CRS + HIPEC.

Conclusion

Primary tumour obstruction or perforation, PCI score and CC score are valuable prognostic factors in the selection of patients with CPM for CRS + HIPEC.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Role of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Appendiceal Tumors and Colorectal Adenocarcinomas

Peritoneal surface disease (PSD) has historically been used interchangeably with the term peritoneal carcinomatosis (PC) and has a dismal natural history. A variety of malignant pathologies, including colorectal and appendiceal primary tumors, can disseminate throughout the peritoneal cavity, leading to bowel obstruction and death. In general, peritoneal spread from high-grade appendiceal and colorectal primaries has the potential of hepatic and distant spread and best classified as PC. Low-grade appendiceal tumors are better categorized as PSD, due to low cellularity, high mucin production, and lack of potential spread outside the peritoneal cavity. Growing international experience with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) over the past 30 years has presented a therapeutic option to patients with PSD from colorectal and appendiceal tumors that can provide significant disease control, as well as potential for previously unattainable long-term survival. The proliferation of HIPEC centers and ongoing prospective trials are helping to standardize HIPEC techniques and patient selection.

Perioperative Systemic Chemotherapy, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy in Patients With Colorectal Peritoneal Metastasis: Results of the Prospective Multicenter Phase 2 COMBATAC Trial

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) as parts of an interdisciplinary treatment concept including systemic chemotherapy can improve survival of selected patients with peritoneal metastatic colorectal cancer (pmCRC). Nevertheless, the sequence of the therapeutic options is still a matter of debate. Thus, the COMBATAC (COMBined Anticancer Treatment of Advanced Colorectal cancer) trial was conducted to evaluate a combined treatment regimen consisting of preoperative systemic polychemotherapy + cetuximab followed by CRS + HIPEC and postoperative systemic polychemotherapy + cetuximab.

PATIENTS AND METHODS

The COMBATAC trial is a prospective, multicenter, open-label, single-arm, single-stage phase 2 trial. Twenty-six patients with synchronous or metachronous colorectal or appendiceal peritoneal carcinomatosis were included. Enrollment was terminated prematurely by the sponsor because of slow recruitment. Progression-free survival as primary end point and overall survival were estimated by the Kaplan-Meier method. Also evaluated were morbidity according to Common Terminology Criteria for Adverse Events v4.0 and feasibility of the combined treatment concept.

RESULTS

Median progression-free survival for the intention-to-treat population (n = 25) was 14.9 months. Median overall survival was not reached during the study duration. Ninety-two adverse events were documented in 16 patients, including 14 serious adverse events in 9 patients. The overall morbidity rate was 64%, and the grade 3/4 morbidity rate was 44%. Of all grade 3/4 morbidity events, 36.4% were related to systemic chemotherapy and 22.7% to surgery, whereas 40.9% were not directly related. There was no treatment-related mortality.

CONCLUSION

The results of the COMBATAC trial show that the multimodal treatment concept consisting of perioperative systemic chemotherapy and CRS + HIPEC is safe and feasible. Progression-free survival in selected patients with colorectal or appendiceal peritoneal metastasis might be improved.

Prognostic impact of the number of lymph nodes examined in different stages of colorectal mucinous adenocarcinoma

BACKGROUND

Mucinous adenocarcinoma (MC) is a special kind of colorectal adenocarcinoma that occurs more frequently in young patients and females, but the prognostic effect of lymph nodes in MC patients is unclear. This population-based study was conducted to analyze the prognostic value of the number of lymph nodes examined in different stages of colorectal MC.

METHODS

We included 17,001 MC patients from the Surveillance, Epidemiology, and End Results program database between 2003 and 2013, of which 12,812 (75%) had >12 lymph nodes examined.

RESULTS

Compared to the group with insufficient lymph nodes examined, patients with more lymph nodes (>12) examined tended to come from east and central America, were more frequently female and young, were diagnosed after 2008, had larger-sized tumors of less differentiated grade and in later stages, had not received radiation therapy and had more positive nodal status. Patients with more lymph nodes (>12) examined demonstrated significantly better survival than those with insufficient lymph nodes examined only in stages II and III (stage II: overall, P<0.001; cancer-specific, P<0.001; stage III: overall, P=0.093; cancer-specific, P=0.032), even though the overall (P<0.001) and cancer-specific survival (P<0.001) showed significant differences between the two groups. Both univariate (overall, HR=0.739, 95% CI=0.703-0.777, P<0.001; cancer-specific, HR=0.742, 95% CI=0.698-0.788, P<0.001) and multivariate (overall, HR=0.601, 95% CI=0.537-0.673, P<0.001; cancer-specific, HR=0.582, 95% CI=0.511-0.664, P<0.001) Cox proportional hazards models verified the association between >12 lymph nodes examined and better survival.

CONCLUSION

More number of lymph nodes (.12) examined significantly increased the survival probability of MC patients in stages II and III, but had no significant influence on patients in stages I and IV, indicating the effect of number of lymph nodes examined was a stage-dependent prognostic factor in clinical utility.

[Surgical treatment of peritoneal metastases of colorectal cancer]

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) may significantly improve overall survival in selected patients with peritoneal metastases of colorectal cancer. For good oncological results complete macroscopic cytoreduction is crucial; furthermore, a linear correlation between peritoneal tumor load, as determined by the peritoneal cancer index (PCI) and overall survival has been demonstrated; therefore, surgical treatment should be initiated as early as possible. Synchronous resection of up to three liver metastases may be performed safely and with good results and no influence on the morbidity. With respect to intraperitoneal chemotherapy, mitomycin C and oxaliplatin are most commonly used and may be regarded as equal; however, for perioperative chemotherapy study results are so far inconclusive with some trials hinting at decreased overall survival following neoadjuvant chemotherapy. Adjuvant therapy is likely to improve overall survival if at least 6 cycles are applied. Early detection of peritoneal metastases is difficult at present but might be facilitated in the future by the use of liquid biopsies, which may detect circulating free tumor-specific DNA or RNA. In the meantime, planned second-look laparotomy should be considered for patients at high risk of peritoneal recurrence. In addition, several international studies are currently evaluating the concept of adjuvant or prophylactic HIPEC. The CRS and HIPEC may be repeated in cases of recurrence and should be considered in suitable patients, applying the same criteria as for primary CRS and HIPEC. A recurrence-free interval of >2 years is associated with a significantly better prognosis.

Patient selection for cytoreductive surgery and HIPEC for the treatment of peritoneal metastases from colorectal cancer

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a viable option for selected patients with peritoneal metastases (PM) from colorectal origin, resulting in long-term survival and even cure in some cases. However, adequate patient selection for this treatment is currently one of the major challenges. The aim of this review is to provide a comprehensive overview of clinically relevant factors associated with overall survival. This may help to guide clinicians through the complex interplay of patient, tumor, and treatment characteristics to adequately select patients who benefit the most from this extensive surgical treatment. First, basic principles of colorectal PM and the CRS and HIPEC treatment will be discussed. According to available literature, especially extent of peritoneal disease, completeness of cytoreduction, and signet ring cell histology have great influence on the outcome after CRS and HIPEC. Other factors that seem to have a negative prognostic value are the presence of liver metastases and the absence of treatment with neo-adjuvant systemic therapy. Prognostic models combining the above-mentioned factors, such as the Colorectal Peritoneal Metastases Prognostic Surgical Score nomogram, may provide clinically relevant tools to use in everyday practice.

Prognosis and value of preoperative radiotherapy in locally advanced rectal signet-ring cell carcinoma

As well known, signet-ring cell carcinoma (SRCC) is a rare histological subtype of colorectal adenocarcinoma, which has been associated with poor prognosis and resistant to non-surgery therapy compared with common adenocarcinoma. In this study, we assessed the effect of preoperative radiotherapy (PRT) for locally advanced rectal SRCC in a large patient group from the Surveillance, Epidemiology, and End Results program (SEER, 1988–2011) database. SRCC was found in 0.9% (n = 622) rectal cancer (RC) patients in our study. In the PRT setting, SRCC had significantly worse cancer-specific survival than mucinous adenocarcinoma and nonmucinous adenocarcinoma patients (log-rank, P < 0.001). In terms of SRCC, stage III RC patients benefited from PRT (log-rank, P < 0.001) while stage II did not (P = 0.095). The multivariate Cox proportional hazard model showed that PRT was an independent benefit factor in stage III rectal SRCC patients (HR, 0.611; 95% CI, 0.407–0.919; P = 0.018). In conclusion, SRCC was an independent predictor of poor prognosis in stage III RC patients, but not in stage II. In the PRT setting of locally advanced RC, SRCC patients had significantly worse prognosis. PRT was an independent prognostic factor associated with improved survival in stage III rectal SRCC.

Therapeutic options for peritoneal metastasis arising from colorectal cancer

Peritoneal metastasis is a common sign of advanced tumor stage, tumor progression or tumor recurrence in patients with colorectal cancer. Due to the improvement of systemic chemotherapy, the development of targeted therapy and the introduction of additive treatment options such as cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), the therapeutic approach to peritoneal metastatic colorectal cancer (pmCRC) has changed over recent decades, and patient survival has improved. Moreover, in contrast to palliative systemic chemotherapy or best supportive care, the inclusion of CRS and HIPEC as inherent components of a multidisciplinary treatment regimen provides a therapeutic approach with curative intent. Although CRS and HIPEC are increasingly accepted as the standard of care for selected patients and have become part of numerous national and international guidelines, the individual role, optimal timing and ideal sequence of the different systemic, local and surgical treatment options remains a matter of debate. Ongoing and future randomized controlled clinical trials may help clarify the impact of the different components, allow for further improvement of patient selection and support the standardization of oncologic treatment regimens for pmCRC. The addition of further therapeutic options such as neoadjuvant intraperitoneal chemotherapy or pressurized intraperitoneal aerosol chemotherapy, should be investigated to optimize therapeutic regimens and further improve the oncological outcome.