Incidence, prevalence and risk factors for peritoneal carcinomatosis from colorectal cancer

Risk factors for metachronous peritoneal carcinomatosis after radical resection for patients with nonmetastatic pT3-4 colon cancer

BACKGROUND

Patients with nonmetastatic pT3-4 colon cancers are prone to develop metachronous peritoneal carcinomatosis (mPC). Risk factors for mPC and the influence of mutant kirsten rat sarcoma viral oncogene (KRAS)/neuroblastoma rat sarcoma (NRAS)/v-raf murine sarcoma viral oncogene homolog B1 (BRAF) and DNA mismatch repair (MMR) status on mPC remain to be described in these patients.

METHOD

All enrolled patients were identified from the prospectively collected colorectal cancer database of a tertiary referral hospital between 2013 and 2018. Multivariate analysis was used to identify risk factors associated with mPC.

RESULTS

Of the 1689 patients with nonmetastatic pT3-4 colon carcinoma, 8.4% (142/1689) progressed to mPC. Endoscopic obstruction (HR = 3.044, p < 0.001), elevated CA125 (HR = 1.795, p = 0.009), pT (T4a vs. T3, HR = 2.745, p < 0.001; T4b vs. T3, HR = 3.167, p = 0.001), pN (N1 vs. N0, HR = 2.592, p < 0.001; N2 vs. N0, HR = 4.049, p < 0.001), less than 12 lymph nodes harvested (HR = 2.588, p < 0.001), mucinous or signet ring cell carcinoma (HR = 1.648, p = 0.038), perineural invasion (HR = 1.984, p < 0.001), and adjuvant chemotherapy (HR = 1.522, p = 0.039) were strongly related to mPC but that mutant KRAS/NRAS/BRAF and MMR status was not associated with mPC.

CONCLUSION

This study identified the high-risk factors for mPC in patients with nonmetastatic pT3-4 colon carcinoma, and these factors should be considered in selective preventive therapy and close follow-up for patients subsequently deemed to have high risk for mPC.

Selection Criteria for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) Treatment in Patients with Peritoneal Metastases

Background: The standard treatment protocol for PIPAC consists of three procedures. Completion of treatment has been shown to be prognostic of improved survival. The aim of this study was to identify predictors for completion of treatment. Methods: Retrospective multicentric cohort study of patients with peritoneal metastases undergoing PIPAC in three PIPAC expert centers. Per protocol (PP) treatment was defined as patients receiving ≥3 PIPACs and was compared to patients receiving <3. Results: Overall, 183 patients had 517 PIPACs. The main reasons for stopping PIPAC were disease progression in 50% patients, bowel obstruction in 15%, patient’s refusal to pursue in 10%, conversion to cytoreductive surgery in 7%, and medical reasons in 8%. Overall, 95 patients (52%) had PP treatment. The PP median OS was 17 vs. 7 months, p = 0.001. PP patients had r ascites (410 ± 100 mL vs. 960 ± 188 mL, p = 0.001), no prior history of bowel obstruction (12% vs. 24%, p = 0.028), and more bimodal treatment (39% vs. 13%, p < 0.001). After multiple regression, bimodal treatment was found as an independent predictive factor for completing PP (OR = 4.202, 95%CI [1.813, 10.630], p < 0.001), along with prior bowel obstruction (OR = 0.389, 95%CI [0.153, 0.920], p = 0.037). Conclusion: The absence of ascites and prior bowel obstruction can help to select patients suitable for PIPAC. Best results seem to be achieved when PIPAC is combined with systemic chemotherapy.

Diagnosis of Peritoneal Carcinomatosis of Colorectal Origin Based on an Innovative Fuzzy Logic Approach

Colorectal cancer represents one of the most important causes worldwide of cancer related morbidity and mortality. One of the complications which can occur during cancer progression, is peritoneal carcinomatosis. In the majority of cases, it is diagnosed in late stages due to the lack of diagnostic tools capable of revealing the early-stage peritoneal burden. Therefore, still associates with poor prognosis and quality of life, despite recent therapeutic advances. The aim of the study was to develop a fuzzy logic approach to assess the probability of peritoneal carcinomatosis presence using routine blood test parameters as input data. The patient data was acquired retrospective from patients diagnosed between 2010-2021. The developed model focuses on the specific quantitative alteration of these parameters in the presence of peritoneal carcinomatosis, which is an innovative approach as regards the literature in the field and validates the feasibility of using a fuzzy logic approach in the noninvasive diagnosis of peritoneal carcinomatosis.

Multimodal CEA-targeted fluorescence and radioguided cytoreductive surgery for peritoneal metastases of colorectal origin

In patients with colorectal peritoneal metastases scheduled for cytoreductive surgery, accurate preoperative estimation of tumor burden and subsequent intraoperative detection of all tumor deposits remains challenging. In this study (ClinicalTrials.gov NCT03699332) we describe the results of a phase I clinical trial evaluating [¹¹¹In]In-DOTA-labetuzumab-IRDye800CW, a dual-labeled anti-carcinoembryonic antigen (anti-CEA) antibody conjugate that enables both preoperative imaging and intraoperative radioguidance and fluorescence imaging. Primary study outcomes are safety and feasibility of this multimodal imaging approach. Secondary outcomes are determination of the optimal dose, correlation between tracer uptake and histopathology and effects on clinical strategy. Administration of [¹¹¹In]In-DOTA-labetuzumab-IRDye800CW is well-tolerated and enables sensitive pre- and intraoperative imaging in patients who receive 10 or 50 mg of the tracer. Preoperative imaging revealed previously undetected lymph node metastases in one patient, and intraoperative fluorescence imaging revealed four previously undetected metastases in two patients. Alteration of clinical strategy based on multimodal imaging occurred in three patients. Thus, multimodal image-guided surgery after administration of this dual-labeled tracer is a promising approach that may aid in decision making before and during cytoreductive surgical procedures.

GECOP-MMC: phase IV randomized clinical trial to evaluate the efficacy of hyperthermic intraperitoneal chemotherapy (HIPEC) with mytomicin-C after complete surgical cytoreduction in patients with colon cancer peritoneal metastases

BACKGROUND

The French PRODIGE 7 trial, published on January 2021, has raised doubts about the specific survival benefit provided by HIPEC with oxaliplatin 460 mg/m² (30 minutes) for the treatment of peritoneal metastases from colorectal cancer. However, several methodological flaws have been identified in PRODIGE 7, specially the HIPEC protocol or the choice of overall survival as the main endpoint, so its results have not been assumed as definitive, emphasizing the need for further research on HIPEC. It seems that the HIPEC protocol with high-dose mytomicin-C (35 mg/m²) is the preferred regime to evaluate in future clinical studies.

METHODS

GECOP-MMC is a prospective, open-label, randomized, multicenter phase IV clinical trial that aims to evaluate the effectiveness of HIPEC with high-dose mytomicin-C in preventing the development of peritoneal recurrence in patients with limited peritoneal metastasis from colon cancer (not rectal), after complete surgical cytoreduction. This study will be performed in 31 Spanish HIPEC centres, starting in March 2022. Additional international recruiting centres are under consideration. Two hundred sixteen patients with PCI ≤ 20, in which complete cytoreduction (CCS 0) has been obtained, will be randomized intraoperatively to arm 1 (with HIPEC) or arm 2 (without HIPEC). We will stratified randomization by surgical PCI (1-10; 11-15; 16-20). Patients in both arms will be treated with personalized systemic chemotherapy. Primary endpoint is peritoneal recurrence-free survival at 3 years. An ancillary study will evaluate the correlation between surgical and pathological PCI, comparing their respective prognostic values.

DISCUSSION

HIPEC with high-dose mytomicin-C, in patients with limited (PCI ≤ 20) and completely resected (CCS 0) peritoneal metastases, is assumed to reduce the expected risk of peritoneal recurrence from 50 to 30% at 3 years.

TRIAL REGISTRATION

EudraCT number: 2019-004679-37; Clinicaltrials.gov: NCT05250648 (registration date 02/22/2022, ).

Survival Outcomes After Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy in Patients with Synchronous Versus Metachronous Onset of Peritoneal Metastases of Colorectal Carcinoma

Background

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment option for peritoneal metastases (PM) from colorectal carcinoma (CRC). Because of considerable morbidity, optimal patient selection is essential. This study was designed to determine the impact of the onset of PM (synchronous vs. metachronous) on survival outcomes after CRS-HIPEC.

Methods

Patients undergoing CRS-HIPEC for colorectal PM in two academic centers in the Netherlands between 2010 and 2020 were eligible for inclusion. Patients were classified as synchronous (s-PM, i.e., diagnosis at time of presentation, staging, or primary surgery) or metachronous onset (m-PM, i.e., diagnosis during follow-up) of colorectal PM. Survival outcomes were compared between groups by Kaplan–Meier survival and Cox regression analyses.

Results

Of 390 included patients, 179 (45.9%) had synchronous onset of colorectal PM. These patients more often presented with higher TN-stage and poor differentiation/signet cell histology. Treatment with perioperative chemotherapy was more common in s-PM patients. m-PM patients experienced more serious postoperative complications (Clavien-Dindo ≥ III). There was no significant difference in disease-free survival (DFS) between s-PM (median 9 months, interquartile range [IQR] 5–15) and m-PM patients (median 8 months, IQR 5–17). Overall survival (OS) was significantly shorter for s-PM (median 28 months, IQR 11–48) versus m-PM patients (median 33 months, IQR 18–66, p = 0.049). Synchronous onset of PM was not independently associated with OS in a multivariable analysis.

Conclusions

Synchronous onset of colorectal PM was associated with poor tumor characteristics and more advanced disease, but was not an independent predictor of survival outcomes after CRS-HIPEC.

In Patients Undergoing CRS/HIPEC for Colorectal Adenocarcinoma with Peritoneal Metastases, Presence of Ascites on Computed Tomography Imaging is not a Prognostic Marker for Survival

Background

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a potentially curative treatment for patients with colorectal peritoneal metastases (CRPM). Patient selection is key to optimizing outcomes after CRS/HIPEC. The aim of this study was to determine the prognostic value of ascites diagnosed on preoperative imaging.

Methods

A prospective database of patients eligible for CRS/HIPEC between 2010 and 2020 was retrospectively analyzed. The presence of ascites, postoperative complications, overall survival (OS), disease-free survival (DFS), and completeness of cytoreduction were assessed. Univariable and multivariable logistic regression was performed to identify independent predictors for outcome.

Results

Of the 235 included patients, 177 (75%) underwent CRS/HIPEC while 58 (25%) were not eligible for CRS/HIPEC. In 42 of the 177 patients (24%) who underwent CRS/HIPEC, ascites was present on preoperative computed tomography (CT) imaging. Peritoneal Cancer Index (PCI) score was significantly higher in patients with preoperative ascites compared with patients without (11 [range 2–30] vs. 9 [range 0–28], respectively; p = 0.011) and complete cytoreduction was more often achieved in patients without ascites (96.3% vs. 85.7%; p = 0.007). There was no significant difference in median DFS and OS after CRS/HIPEC between patients with and without ascites {10 months (95% confidence interval [CI] 7.1–12.9) vs. 9 months (95% CI 7.2–10.8), and 25 months (95% 9.4–40.6) vs. 27 months (95% CI 22.4–31.6), respectively}.

Conclusions

Ascites on preoperative imaging was not associated with worse survival in CRS/HIPEC patients with CRPM. Therefore, excluding patients from CRS/HIPEC based merely on the presence of ascites is not advisable.

Update for Advance CAR-T Therapy in Solid Tumors, Clinical Application in Peritoneal Carcinomatosis From Colorectal Cancer and Future Prospects

Latest advances in the field of cancer immunotherapy have developed the (Chimeric Antigen Receptor) CAR-T cell therapy. This therapy was first used in hematological malignancies which obtained promising results; therefore, the use of CAR-T cells has become a popular approach for treating non-solid tumors. CAR-T cells consist of T-lymphocytes that are engineered to express an artificial receptor against any surface antigen of our choice giving us the capacity of offering precise and personalized treatment. This leaded to the development of CAR-T cells for treating solid tumors with the hope of obtaining the same result; however, their use in solid tumor and their efficacy have not achieved the expected results. The reason of these results is because solid tumors have some peculiarities that are not present in hematological malignancies. In this review we explain how CAR-T cells are made, their mechanism of action, adverse effect and how solid tumors can evade their action, and also we summarize their use in colorectal cancer and peritoneal carcinomatosis.

What is the Risk for Peritoneal Metastases and Survival Afterwards in T4 Colon Cancers?

BACKGROUND

Patients with T4 colon adenocarcinomas have an increased risk of peritoneal metastases (PM) but the histopathologic risk factors for its development are not well-described.

OBJECTIVE

The purpose of this study was to determine factors associated with PM, time to recurrence, and survival after recurrence among patients with T4 colon cancer.

PATIENTS AND METHODS

Patients with pathologic T4 colon cancer who underwent curative resection from 2005 to 2017 were identified from a prospectively maintained institutional database and classified by recurrence pattern: (a) none - 68.8%; (b) peritoneal only - 7.9%; (c) peritoneal and extraperitoneal - 9.9%; and (d) extraperitoneal only - 13.2%. Associations between PM development and patient, primary tumor, and treatment factors were assessed.

RESULTS

Overall, 151 patients were analyzed, with a median follow-up of 66.2 months; 27 patients (18%) developed PM (Groups B and C) and 20 (13%) patients recurred at non-peritoneal sites only (Group D). Median time to developing metastases was shorter for Groups B and C compared with Group D (B and C: 13.7 months; D: 46.7 months; p = 0.022). Tumor deposits (TDs) and nodal stage were associated with PM (p < 0.05), and TDs (p = 0.048) and LVI (p = 0.015) were associated with additional extraperitoneal recurrence. Eleven (41%) patients with PM underwent salvage surgery, and median survival after recurrence was associated with the ability to undergo cytoreduction (risk ratio 0.20, confidence interval 0.06-0.70).

CONCLUSION

PM risk after resection of T4 colon cancer is independently associated with factors related to lymphatic spread, such as N stage and TDs. Well-selected patients can undergo cytoreduction with long-term survival. These findings support frequent postoperative surveillance and aggressive early intervention, including cytoreduction.

Lobaplatin hyperthermic intraperitoneal chemotherapy plus cytoreduction and rechallenge using cetuximab for wild-type RAS peritoneal metastatic colon cancer: a case report and literature review

BACKGROUND

Synchronous peritoneal metastasis of colorectal cancer usually predicts a bleak prognosis. Hyperthermic intraperitoneal chemotherapy (HIPEC) and cytoreductive surgery (CRS) have brought a glimmer of hope to the treatment of peritoneal cancer. Few cases treated with lobaplatin have been reported in the literature and the regimen is controversial. In this case, the comprehensive treatment scheme of lobaplatin-based HIPEC plus CRS and rechallenge using cetuximab plus systemic chemotherapy is effective, especially for the patients with left colon cancer (wild-type RAS).

CASE PRESENTATION

A 49 year-old man with signet ring cell carcinoma of sigmoid colon with extensive abdominal metastasis (wild-type RAS) was hospitalized with prolonged abdominal pain, distention and abdominal mass. After receiving HIPEC with lobaplatin and XELOX regimen combined with cetuximab for eight cycles, the patient had been treated with the FOLFIRI regimen and cetuximab for 24 cycles, which discontinued due to myelosuppression. Because the disease recurred unfortunately 4 months later, the FOLFIRI + cetuximab regimen was initiated again and stopped after two cycles. Intestinal obstruction occurred 1 month later, so open total colectomy, CRS + HIPEC and ileorectal anastomosis were performed. Capecitabine adjuvant chemotherapy was administered, followed by the maintenance therapy with FOLFIRI + cetuximab regimen. After that, the patient has been in relatively stable condition. By August 2021, the overall survival is more than 45 months, which displays significant curative effect.

CONCLUSION

For peritoneal metastasis from left colon cancer, the management with CRS + lobaplatin HIPEC and rechallenge of systemic chemotherapy plus targeted medicine based on gene detection can dramatically improve prognosis and extend the overall survival.

Use of ascitic CEA levels as a predictive value for distant metastasis in high-risk stage II and III colorectal cancer

PURPOSE

This study aimed to analyze the effect of ascitic carcinoembryonic antigen (CEA) levels on the long-term oncologic outcomes of colorectal cancer (CRC) following curative treatment.

METHODS

A total of 191 patients with stage II/III CRC were included. CEA was analyzed on the peritoneal fluid samples taken at the start of each surgery. Long-term oncologic outcomes were analyzed using known risk factors for recurrence in CRC.

RESULT

Multivariate analysis of recurrence showed that lymphatic invasion (hazards ratio (HR) 2.7, 95% confidence interval (CI) 1.1-7, p = 0.038), vascular invasion (HR 2.8, 95% CI 1.2-6.3, p = 0.013), mucinous cancer (HR 3.6, 95% CI 1.3-10.1, p = 0.017), and peritoneal fluid CEA exceeding 5 ng/dl (odds ratio 3.1, 95% CI 1.2-7.7, p = 0.017) were significant risk factors. There were 14 patients with liver metastasis, 11 of whom had high ascitic CEA levels and no peritoneal metastasis. Additionally, eight had lung metastasis, and seven of them had high ascitic CEA levels.

CONCLUSION

High ascitic CEA levels showed significantly lower disease-free survival and were significantly associated with distant metastasis in the lung and liver.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: A Systematic Review

BACKGROUND

Combined treatment modality of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is emerging as an alternative option for colorectal peritoneal metastases, but there is ambiguity regarding patient selection, treatment protocols, and efficacy.

OBJECTIVE

To elaborate on the patient characteristics, hyperthermic intraperitoneal chemotherapy protocol and health outcomes in colorectal peritoneal metastases patients undergoing a combination of hyperthermic intraperitoneal chemotherapy and cytoreductive surgery and provide guidance for future studies.

DATA SOURCES

A Medline search for English language studies published between 2004 and 2019.

STUDY SELECTION

Medical subject headings and key terms, including: hyperthermic intraperitoneal chemotherapy, colorectal peritoneal metastases, colorectal cancer and combinations thereof as per guidelines.

MAIN OUTCOME MEASURES

Overall survival, disease-free survival, and morbidity and mortality rates.

RESULTS

Of the 26 included studies, 42% were published between 2016 and 2019. More than half of the studies were retrospective in nature and conducted in tertiary specialized centers outside of the United States. The median age range was 44 to 62 years. Mitomycin C-based therapy was seen in 50% of studies. Mean weighted median disease-free survival for 11 studies was 15 months (9 to 36 months). Median OS ranged from 12 to 63 months, with an average of 33.6 months among 20 studies. Overall morbidity varied from 11% to 56%, with a weighted mean of 29% in 18 studies. Mortality ranged from 0 to 34%, with a weighted mean of 4% in 15 studies.

LIMITATIONS

Despite careful study selection, variability in methodology of the included studies can limit review findings.

CONCLUSION

Due to study heterogeneity, and a recent large, randomized trial showing no overall benefit, use of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy in colorectal peritoneal metastases patients is highly controversial. Further standardized controlled studies can help uniformly define and build consensus among the medical community on patient eligibility and the optimal hyperthermic intraperitoneal chemotherapy techniques.

PROSPERO

Registered on March 3, 2020, CRD42020146942.

Treatment for Peritoneal Metastasis of Patients With Colorectal Cancer

From the perspective of survival outcomes, the cancer survival of colorectal cancer (CRC) in the whole stage has improved. Peritoneal metastasis (PM) is found in approximately 8% to 15% of patients with CRC, with a poorer prognosis than that associated with other sites of metastases. Randomized controlled trials and up-to-date meta-analyses provide firm evidence that cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) could significantly improve overall survival compared with systemic chemotherapy alone in selected patients with CRC-PM. Practical guidelines recommend that the management of CRC-PM should be led by a multidisciplinary team carried out in experienced centers and consider CRS plus HIPEC for selected patients. In this review, we aim to provide the latest results of land mark studies and an overview of recent insights with regard to the management of CRC-PM.

Severe pulmonary complications after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy are common and contribute to decreased overall survival

BACKGROUND AND OBJECTIVES

Extensive abdominal surgery is associated with the risk of postoperative pulmonary complications. This study aims to explore the incidence and risk factors for developing postoperative pulmonary complications after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy and to analyze how these complications affect overall survival.

METHODS

Data were collected on 417 patients undergoing surgery between 2007 and2017 at Uppsala University Hospital, Sweden. Postoperative pulmonary complications were graded according to the Clavien-Dindo classification system where Grade ≥ 3 was considered a severe complication. A logistic regression analysis was used to analyze risk factors for postoperative pulmonary complications and a Cox proportional hazards model to assess impact on survival.

RESULTS

Seventy-two patients (17%) developed severe postoperative pulmonary complications. Risk factors were full thickness diaphragmatic injury and/or diaphragmatic resection [OR 5.393, 95% CI 2.924-9.948, p = < 0.001]. Severe postoperative pulmonary complications, in combination with non-pulmonary complications, contributed to decreased overall survival [HR 2.285, 95% CI 1.232-4.241, p = 0.009].

CONCLUSIONS

Severe postoperative pulmonary complications were common and contributed to decreased overall survival. Full thickness diaphragmatic injury and/or diaphragmatic resection were the main risk factors. This finding emphasizes the need for further research on the mechanisms behind pulmonary complications and their association with mortality.

Peritoneal Metastasis: Current Status and Treatment Options

Simple Summary

Surgical and locoregional treatments of peritoneal metastasis, e.g., from colorectal cancer, has gained increasing acceptance after the publication of excellent patient outcomes from many groups around the world. Apart from systemic chemotherapy and surgical removal of the tumor, locoregional therapies such as HIPEC or PIPAC may improve tumor control. Understanding the molecular characteristics of peritoneal metastasis is crucial to evolve future therapeutic strategies for peritoneal metastasis. This includes the genetic background of PM, which is often different from other sites of metastasis, and promotes peritoneal dissemination and the growth of tumor cells. Growing knowledge and insight into the physiology of the peritoneal tumor microenvironment and the specific role of the immune system in this compartment may provide a critical step to move locoregional therapy to the next level. This review summarizes the current knowledge and highlights the molecular characteristics of peritoneal metastasis.

Abstract

Peritoneal metastasis (PM) originating from gastrointestinal cancer was considered a terminal disease until recently. The advent of better systemic treatment, a better understanding of prognostic factors, and finally, the advent of novel loco-regional therapies, has opened the door for the multimodal treatment of PM. These strategies, including radical surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) showed surprisingly good results, leading to the prolonged survival of patients with peritoneal metastasis. This has triggered a significant body of research, leading to the molecular characterization of PM, which may further help in the development of novel treatments. This review summarizes current evidence on peritoneal metastasis and explores potential novel mechanisms and therapeutic approaches to treat patients with peritoneal metastasis.

Primary and metastatic peritoneal surface malignancies

Peritoneal surface malignancies comprise a heterogeneous group of primary tumours, including peritoneal mesothelioma, and peritoneal metastases of other tumours, including ovarian, gastric, colorectal, appendicular or pancreatic cancers. The pathophysiology of peritoneal malignancy is complex and not fully understood. The two main hypotheses are the transformation of mesothelial cells (peritoneal primary tumour) and shedding of cells from a primary tumour with implantation of cells in the peritoneal cavity (peritoneal metastasis). Diagnosis is challenging and often requires modern imaging and interventional techniques, including surgical exploration. In the past decade, new treatments and multimodal strategies helped to improve patient survival and quality of life and the premise that peritoneal malignancies are fatal diseases has been dismissed as management strategies, including complete cytoreductive surgery embedded in perioperative systemic chemotherapy, can provide cure in selected patients. Furthermore, intraperitoneal chemotherapy has become an important part of combination treatments. Improving locoregional treatment delivery to enhance penetration to tumour nodules and reduce systemic uptake is one of the most active research areas. The current main challenges involve not only offering the best treatment option and developing intraperitoneal therapies that are equivalent to current systemic therapies but also defining the optimal treatment sequence according to primary tumour, disease extent and patient preferences. New imaging modalities, less invasive surgery, nanomedicines and targeted therapies are the basis for a new era of intraperitoneal therapy and are beginning to show encouraging outcomes.

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) in peritoneal sarcomatosis-A systematic review and meta-analysis

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) play an important role in the treatment of various peritoneal surface malignancies, but its efficacy in peritoneal sarcomatosis (PS) remains unknown. Hence, we performed a systematic review and meta-analysis to investigate outcomes of CRS-HIPEC in PS, in accordance with PRISMA guidelines. 16 studies with a total of 320 patients were included in the meta-analysis. Pooled mean length of hospital stay after CRS-HIPEC was 16.0 days (95% CI: 12.2-19.8) and rate of serious complications was 17.4% (95% CI: 9.8-26.3). The median DFS was 12.0 months (95% CI: 8.0-16.0) and the 5-year DFS was 21.8% (95% CI: 13.2-31.7). Overall pooled median OS was 29.3 months (95% CI: 23.8-34.8), with a 5-year OS of 35.3% (95% CI: 26.3-44.8). Subgroup analysis showed that patients with CC-0 cytoreduction had a higher median OS of 34.6 months (95% CI: 23.2-45.9). Median OS for patients with a primary tumour histology of leiomyosarcoma and liposarcoma was 33.5 months (95% CI: 15.9-51.1) and 39.1 months (95% CI: 20.8-57.5) respectively. The site of recurrence was locoregional in 57.3% (95% CI: 38.9-74.8), distant in 17.3% (95% CI: 3.9-35.6), and both in 17.4% (95% CI: 5.8-32.2). In conclusion, our results suggest that CRS-HIPEC may improve outcomes in a select group of PS patients.

Clinical and Molecular Features in Patients Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Carcinosis from Colorectal Cancer

PURPOSE

Careful patient selection plays a crucial role in avoiding overtreatment and further increases survival rates in patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for colorectal cancer (CRC) with peritoneal metastases (PM).

METHODS

The clinical and molecular factors influencing survival in patients who had undergone CRS with HIPEC between January 2015 and December 2018 were analyzed.

RESULTS

Sixty-six patients underwent CRS with HIPEC during the study period. The median overall survival (OS) was 36 months, with a 3-year OS of 43%. Multivariate analysis revealed increased PCI (HR: 1.21; 95% CI: 1.02-1.41; p = 0.020), right-sided primary tumor (HR: 3.01; 95% CI: 1.27-7.13; p = 0.017), and BRAF V600E mutation (HR: 4.55; 95% CI: 1.21-17.21; p = 0.025) as independent predictors for worse OS.

CONCLUSION

In addition to confirming the prognostic role of PCI, our study extends the role of BRAF mutation and right primary tumor location as markers for worse prognosis.

Comparison of model fit and discriminatory ability of M category as defined by the 7th and 8th editions of the tumor-node-metastasis classification of colorectal cancer and the 9th edition of the Japanese classification

Background

In transitioning from the 7th edition of the tumor‐node‐metastasis classification (TNM‐7) to the 8th edition (TNM‐8), colorectal cancer with peritoneal metastasis was newly categorized as M1c. In the 9th edition of the Japanese Classification of colorectal, appendiceal, and anal carcinoma (JPC‐9), M1c is further subdivided into M1c1 (without other organ involvement) and M1c2 (with other organ involvement). This study aimed to compare the model fit and discriminatory ability of the M category of these three classification systems, as no study to date has made this comparison.

Methods

The study population consisted of stage IV colorectal cancer patients who were referred to the National Cancer Center Hospital from 2000 to 2017. The Akaike information criterion (AIC), Harrell's concordance index (C‐index), and time‐dependent receiver operating characteristic (ROC) curves were used to compare the three classification systems. Subgroup analyses, stratified by initial treatment year, were also performed.

Results

According to TNM‐8, 670 (55%) patients had M1a, 273 (22%) had M1b, and 279 (23%) had M1c (87 M1c1 and 192 M1c2 using JPC‐9) tumors. Among the three classification systems, JPC‐9 had the lowest AIC value (JPC‐9: 10546.3; TNM‐7: 10555.9; TNM‐8: 10585.5), highest C‐index (JPC‐9: 0.608; TNM‐7: 0.598; TNM‐8: 0.599), and superior time‐dependent ROC curves throughout the observation period. Subgroup analyses were consistent with these results.

Conclusions

While the revised M category definition did not improve model fit and discriminatory ability from TNM‐7 to TNM‐8, further subdivision of M1c in JPC‐9 improved these parameters. These results support further revisions to M1 subcategories in future editions of the TNM classification system.

Seeing the whole picture: Added value of MRI for extraperitoneal findings in CRS-HIPEC candidates

PURPOSE

In colorectal cancer (CRC) patients the selection of suitable cytoreductive surgery and hyperthermic peritoneal chemotherapy (CRS-HIPEC) candidates is based on the location and extent of peritoneal metastases (PM) and presence of extraperitoneal metastases. MRI is increasingly being used to accurately assess the extent of PM, however, the significance of extraperitoneal findings in these scans has never been evaluated before.

METHODS

CRC patients who had undergone an additional MRI scan after standard work-up with CT for preoperative staging between January 2016-January 2020 were selected. CT and MRI reports were reviewed for new abdominopelvic extra-peritoneal findings on MRI (MR-EPF) and MR-EPFs concerning lesions previously indicated as equivocal (uncertain benign/malignant) on CT. Reference standard were surgical results or follow-up imaging.

RESULTS

In 158 included patients 60 MR-EPFs (in 58/158 patients) were noted: twenty-six (43%) were new findings and thirty-four (57%) were equivocal findings on CT. Of the 34 equivocal findings 27 were 'rejected/less likely malignant' and 7 'confirmed/more likely malignant' based on MRI. In 29 patients (18%) the MR-EPFs had direct influence on treatment planning. Three patients (2%), eligible for CRS-HIPEC on CT, were deemed inoperable due to MR-EPFs.

CONCLUSION

MRI had an added value in more than a third of the patients due to abdominopelvic extraperitoneal findings that were undetected or indeterminate on CT and therefore influenced the treatment in a substantial part of the patients. Combined with the known accurate detection of peritoneal disease on MRI, MRI seems a logical addition to the diagnostic workup of potential CRS-HIPEC candidates.

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.

Outcomes of Stenting as a Bridge to Surgery in Malignant Colonic Obstruction, With Emphasis on Perforation Rate and Clinical Success

BACKGROUND

Colonic stent placement in acute malignant obstruction has proven to be an alternative for emergency surgery. It has been associated with reduced stoma creation and postoperative morbidity. Concerns have risen that manipulation of the tumor and risk of perforation might result in lower disease-free survival. Therefore, we investigated the long-term outcomes of stenting as a bridge to surgery in these patients, with emphasis on clinical success of the stenting procedure.

METHODS

We performed a comparative study in the Rijnstate Hospital in Arnhem, The Netherlands. Data were collected from patients who underwent colonic stenting procedures or acute surgical resection due to malignant obstruction performed between 2007 and 2015. Patients treated with palliative intent were excluded.

RESULTS

We included 92 patients, 66 underwent stent placement and 26 had an acute surgical resection. Technical and clinical success rates of the stenting procedures were 94% and 82%, respectively. No significant differences in demographic, tumor or stenting characteristics were found for patients with clinically (un)successful stent placement or stent-related perforations. Patients with unsuccessful stent procedures or perforation had higher rates of open procedures and rescue colostomy. Survival rates were similar for patients who underwent stent placements compared with acute resection. We found no significant differences in survival between patients with successful compared with unsuccessful procedures or perforation.

CONCLUSIONS

Survival rates of patients who underwent colonic stenting are similar to those of patients who had an acute resection. No negative effects on survival were observed for clinically failed stenting procedures or stent-related perforations.

Hyperthermic Intraperitoneal Chemotherapy for Ovarian and Colorectal Cancer: A Review

Importance

The peritoneal surface is a common site of disease in ovarian and colorectal cancer. Peritoneal metastases carry a poor prognosis, despite maximal therapeutic efforts, including surgical removal of tumor deposits and intravenous chemotherapy. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a single intraoperative procedure that delivers chemotherapy directly into the abdominal cavity, leading to high intracellular drug concentration at the peritoneal surface. This review describes the current knowledge regarding the mechanism of action, safety, and efficacy of HIPEC in the treatment of peritoneal metastases from epithelial ovarian and colorectal cancers and explores current knowledge gaps.

Observations

Toxic effects of HIPEC are limited. Evidence from a randomized trial shows improved recurrence-free and overall survival after HIPEC in patients with ovarian cancer who are ineligible for primary cytoreductive surgery (CRS). The effect of HIPEC for patients with ovarian cancer undergoing primary CRS or CRS for recurrent disease has not yet been determined, and results of ongoing trials must be awaited. A recent study in patients with peritoneal metastases from colorectal cancer did not show a benefit of HIPEC when added to perioperative chemotherapy.

Conclusions and Relevance

Based on available evidence, various international guidelines include the option to add HIPEC to interval CRS for patients with stage III ovarian cancer. The role of HIPEC in colorectal cancer is less well defined. Future studies will need to tailor patient selection, timing, and optimal regimens of HIPEC to improve the effectiveness of this specialized treatment in ovarian, colorectal, and other tumor types.

A Comprehensive Overview of Colon Cancer- A Grim Reaper of the 21st Century

A few decades ago, the incidence of colorectal cancer (CRC) was low and is now the fourth in the list of deadly cancers producing nearly a million deaths annually. A population that is aging along with risk factors such as smoking, obesity, sedentary lifestyle with little or no physical activity, and non-healthy food habits of developed countries can increase the risk of colorectal cancer. The balance in gut microbiota and the metabolites produced during bacterial fermentation within the host plays a significant role in regulating intestinal diseases as well as colorectal cancer development. Recent progress in the understanding of illness resulted in multiple treatment options such as surgery, radiation, and chemotherapy, including targeted therapy and multitherapies. The treatment plan for CRC depends on the location, stage and grade of cancer as well as genomic biomarker tests. Despite all the advancements made in the genetic and molecular aspects of the disease, the knowledge seems inadequate as the drug action as well as the wide variation in drug response did not appear strongly correlated with the individual molecular and genetic characteristics, which suggests the requirement of comprehensive molecular understanding of this complex heterogeneous disease. Furthermore, multitherapies or a broad spectrum approach, which is an amalgamation of the various promising as well as effective therapeutic strategies that can tackle heterogeneity and act on several targets of the disease, need to be validated in clinical studies. The latest treatment options have significantly increased the survival of up to three years in the case of advanced disease. The fact that colorectal cancer is developed from a polypoid precursor, as well as the symptoms of the disease that occur at an advanced stage, underlines how screening programs can help early detection and decrease mortality as well as morbidity from CRC.

A Prediction Model for Metachronous Peritoneal Carcinomatosis in Patients with Stage T4 Colon Cancer after Curative Resection

(1) Background: The aim of this study was to develop a prediction model for assessing individual mPC risk in patients with pT4 colon cancer. Methods: A total of 2003 patients with pT4 colon cancer undergoing R0 resection were categorized into the training or testing set. Based on the training set, 2044 Cox prediction models were developed. Next, models with the maximal C-index and minimal prediction error were selected. The final model was then validated based on the testing set using a time-dependent area under the curve and Brier score, and a scoring system was developed. Patients were stratified into the high- or low-risk group by their risk score, with the cut-off points determined by a classification and regression tree (CART). (2) Results: The five candidate predictors were tumor location, preoperative carcinoembryonic antigen value, histologic type, T stage and nodal stage. Based on the CART, patients were categorized into the low-risk or high-risk groups. The model has high predictive accuracy (prediction error ≤5%) and good discrimination ability (area under the curve >0.7). (3) Conclusions: The prediction model quantifies individual risk and is feasible for selecting patients with pT4 colon cancer who are at high risk of developing mPC.

Recurrence patterns and their effects on clinical outcomes after R1 resection of colorectal liver metastases: a propensity score-matched analysis

PURPOSE

The prognostic significance of the surgical margin status remains controversial for patients who undergo hepatectomy for colorectal liver metastases. This study evaluated the influence of R1 resection on recurrence patterns and prognosis in these patients.

METHODS

Between January 2001 and December 2016, 232 consecutive Japanese patients underwent initial hepatic resection for colorectal liver metastases. Their medical records were reviewed to evaluate recurrence and survival outcomes.

RESULTS

Relative to patients with R0 resection, patients with R1 resection had significantly poorer recurrence-free survival (RFS) and overall survival (OS). However, after propensity score matching, there were no significant differences in RFS and OS associated with the margin status. Nevertheless, R1 resection was associated with a significantly higher incidence of intrahepatic recurrence and early recurrence, while R0 resection was associated with a significantly higher re-resection rate for hepatic recurrence. Only eight of 55 patients with R1 resection developed recurrence at the R1 resection margin, whereas 36 patients developed recurrence at other sites/organs.

CONCLUSION

Among patients with similar characteristics, R1 resection does not affect long-term outcomes. This suggests that R1 resection itself is not a cause of a poor prognosis, but rather a potent indicator of aggressive tumor biology.

Risk of metachronous peritoneal metastases in patients with pT4a versus pT4b colon cancer: An international multicentre cohort study

INTRODUCTION

With evolving treatment strategies aiming at prevention or early detection of metachronous peritoneal metastases (PM), identification of high-risk colon cancer patients becomes increasingly important. This study aimed to evaluate differences between pT4a (peritoneal penetration) and pT4b (invasion of other organs/structures) subcategories regarding risk of PM and other oncological outcomes.

MATERIALS AND METHODS

From eight databases deriving from four countries, patients who underwent curative intent treatment for pT4N0-2M0 primary colon cancer were included. Primary outcome was the 5-year metachronous PM rate assessed by Kaplan-Meier analysis. Independent predictors for metachronous PM were identified by Cox regression analysis. Secondary endpoints included 5-year local and distant recurrence rates, and 5-year disease free and overall survival (DFS, OS).

RESULTS

In total, 665 patients with pT4a and 187 patients with pT4b colon cancer were included. Median follow-up was 38 months (IQR 23-60). Five-year PM rate was 24.7% and 12.2% for pT4a and pT4b categories, respectively (p = 0.005). Independent predictors for metachronous PM were female sex, right-sided colon cancer, peritumoral abscess, pT4a, pN2, R1 resection, signet ring cell histology and postoperative surgical site infections. Five-year local recurrence rate was 14% in both pT4a and pT4b cancer (p = 0.138). Corresponding five-year distant metastases rates were 35% and 28% (p = 0.138). Five-year DFS and OS were 54% vs. 62% (p = 0.095) and 63% vs. 68% (p = 0.148) for pT4a vs. pT4b categories, respectively.

CONCLUSION

Patients with pT4a colon cancer have a higher risk of metachronous PM than pT4b patients. This observation has important implications for early detection and future adjuvant treatment strategies.

Differences in Sociodemographic Disparities Between Patients Undergoing Surgery for Advanced Colorectal or Ovarian Cancer

BACKGROUND

Cytoreductive surgery (CRS) for ovarian cancer with peritoneal metastases (OPM) is an established treatment, yet access-related racial and socioeconomic disparities are well documented. CRS for colorectal cancer with peritoneal metastases (CRPM) is garnering more widespread acceptance, and it is unknown what disparities exist with regards to access.

METHODS

This retrospective cross-sectional multicenter study analyzed medical records from the National Cancer Database from 2010 to 2015. Patients diagnosed with CRPM or ORP only and either no or confirmed resection were included. Patient- and facility-level characteristics were analyzed using uni- and multivariable logistic regressions to identify associations with receipt of CRS.

RESULTS

A total of 6634 patients diagnosed with CRPM and 14,474 diagnosed with OPM were included in this study. Among patients with CRPM, 18.1% underwent CRS. On multivariable analysis, female gender (odds ratio [95% CI] 2.04 [1.77-2.35]; P < 0.001) and treatment at an academic or research facility (OR 1.55 [1.17-2.05]; P = 0.002) were associated with CRS. Among patients with OPM, 87.1% underwent CRS. On multivariable analysis, treatment at facilities with higher-income patient populations was positively associated with CRS, while age (OR 0.97 [0.96-0.98]; P < .0001), use of nonprivate insurance (OR 0.69 [0.56-0.85]; P = 0.001), and listed as Black (OR 0.62 [0.45-0.86]; P = 0.004) were negatively associated with CRS.

CONCLUSION

There were more systemic barriers to CRS for patients with OPM than for patients with CRPM. As CRS becomes more widely practiced for CRPM, it is likely that more socioeconomic and demographic barriers will be elucidated.

Interleukin 10 level in the peritoneal cavity is a prognostic marker for peritoneal recurrence of T4 colorectal cancer

Peritoneal recurrence (PR) is a major relapse pattern of colorectal cancer (CRC). We investigated whether peritoneal immune cytokines can predict PR. Cytokine concentrations of peritoneal fluid from CRC patients were measured. Patients were grouped according to peritoneal cancer burden (PCB): no tumor cells (≤ pT3), microscopic tumor cells (pT4), or gross tumors (M1c). Cytokine concentrations were compared among the three groups and the associations of those in pT4 patients with and without postoperative PR were assessed. Of the ten cytokines assayed, IL6, IL10, and TGFB1 increased with progression of PCB. Among these, IL10 was a marker of PR in pT4 (N = 61) patients based on ROC curve (p = 0.004). The IL10 cut-off value (14 pg/mL) divided patients into groups with a low (7%, 2 of 29 patients) or high (45%, 16 of 32 patients) 5-year PR (p < 0.001). Multivariable analysis identified high IL10 levels as the independent risk factor for PR. Separation of patients into training and test sets to evaluate the performance of IL10 cut-off model validated this cytokine as a risk factor for PR. Peritoneal IL10 is a prognostic marker of PR in pT4 CRC. Further research is necessary to identify immune response of intraperitoneal CRC growth.

CD244+ polymorphonuclear myeloid‑derived suppressor cells reflect the status of peritoneal dissemination in a colon cancer mouse model

Despite the recent development of chemotherapeutic agents, the prognosis of colorectal cancer (CRC) patients with peritoneal dissemination (PD) remains poor. The tumor immune microenvironment (TIME) has drawn attention as a key contributing factor of tumor progression. Of TIME components, myeloid-derived suppressor cells (MDSCs) are considered to play a responsible role in the immunosuppressive characteristics of the TIME. MDSCs are classified into two major subsets: Monocytic MDSCs (M-MDSCs) and polymorphonuclear MDSCs (PMN-MDSCs). Therefore, we hypothesize that MDSCs would play important roles in the PD-relevant TIME and PD progression. To address this hypothesis, we established PD mouse models. As the PD nodules consisted scarcely of immune cells, we focused on the peritoneal cavity, but not PD nodule, to evaluate the PD-relevant TIME. As a result, intraperitoneal PMN-MDSCs were found to be substantially increased in association with PD progression. Based on these results, we phenotypically and functionally verified the usefulness of CD244 for identifying PMN-MDSCs. In addition, the concentrations of interleukin (IL)-6 and granulocyte-colony stimulating factor (G-CSF) were significantly increased in the peritoneal cavity, both of which were produced by the tumors and thought to contribute to the increases in the PMN-MDSCs. In vivo depletion of the PMN-MDSCs by anti-Ly6G monoclonal antibody (mAb) significantly inhibited the PD progression and reverted CD4⁺ and CD8⁺ T cells in the peritoneal cavity and the peripheral blood. Collectively, these results suggest that the targeted therapy for PMN-MDSCs would provide not only new therapeutic value but also a novel strategy to synergize with T-cell-based immunotherapy for CRC-derived PD.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in the management of peritoneal surface malignancies - An evidence-based review

BACKGROUND

Traditionally, peritoneal surface malignancies (PSM) were considered terminal diseases because of their advanced nature, therefore, systemic chemotherapy was given with palliative intent only. As a result, very poor survival outcomes were observed. But with the introduction of complete Cytoreductive surgery (CRS) and Hyperthermic intraperitoneal chemotherapy (HIPEC), the scenario has changed dramatically.

METHODOLOGY

An objective electronic database search was performed in Pubmed, NLM Catalog, Google scholar, Bookshelf, and Pubmed Central published in the time period from 2000 till 2020. All the randomized studies were included. In the absence of randomized studies, both prospective and retrospective studies were included. The outcomes of HIPEC were measured in terms of median survival, disease-free survival, overall survival, complications and drug toxicities.

RESULTS

CRS and HIPEC are considered the standard of care for PMP and MPM even in the absence of level 1 evidence due to lack of an effective alternative treatment. In colorectal and gastric cancer, several phase-three trials are showing overall survival benefit in selected cases while there is a prophylactic and palliative role of HIPEC in gastric cancer. Three reported phase 3 trials showed positive results in ovarian cancer. In peritoneal sarcomatosis, the role of HIPEC is yet to be proven.

CONCLUSION

The patient selection is the key to the successful outcomes after HIPEC. HIPEC should be performed by the experienced surgeons in specialized centres with a strong critical care and intensive care support to reduce the morbidity and mortality. Ongoing trials and future directions will prove to be an indispensable arm in the oncological armamentarium.

Outcomes following synchronous liver resection, cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for colorectal liver and peritoneal metastases: A bi-institutional study

PURPOSE

Synchronous liver resection, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for colorectal liver (CRLM) and peritoneal metastases (CRPM) has traditionally been contraindicated. However, latest practice promotes specialist, multidisciplinary-led consideration for select patients. This study aimed to evaluate the perioperative and oncological outcomes of synchronous resection in the management of CRLM and CRPM from two tertiary referral centres.

METHOD

This bi-institutional, retrospective, cohort study included patients undergoing simultaneous liver resection, CRS and HIPEC for metastatic colorectal cancer from 2013 to 2020. Patients treated with ablative liver techniques, staged operative approaches and extra abdominal disease were excluded. Overall survival (OS) and disease-free survival (DFS) rates were assessed. Univariate and multivariate analyses identified variables associated with survival and major morbidity (Clavien-Dindo grade III/IV).

RESULTS

Twenty-three patients were included. The median peritoneal carcinomatosis index (PCI) was 9 (range 0-22). There were two major liver resections and 21 minor resections. CC-0 resections were achieved in all patients. Major morbidity occurred in 7 patients. There were no deaths at 90 days. PCI was independently associated with morbidity (p = 0.04). PCI >10 (p = 0.069), major morbidity (p = 0.083) and presence of KRAS mutation (p = 0.052) approached significance for poor OS. Median follow up was 21 months (4-54 months). Median OS was 37 months, 3-year survival 54%, and median DFS 18 months.

CONCLUSION

Synchronous liver resection, cytoreductive surgery and HIPEC is feasible in selected patients with low-volume CRPM and CRLM. Increasing PCI is associated with postoperative major morbidity, and should be considered during operative planning.

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.

New insights in the pathology of peritoneal surface malignancy

Pathology is central to the management of peritoneal surface malignancy. This article highlights some recent advances that have had an impact on patient management or could do so in the near future. Malignant peritoneal mesothelioma, particularly the epithelioid subtype, is amenable to radical therapy in selected cases, and factors such as ki67 proliferation index, expression of BAP1 and mutation in CDKN2A show promise as prognostic indicators. Our understanding of multicystic mesothelioma has improved in recent years; it is a true neoplasm for which surgery may be indicated. Serous carcinomas involving the peritoneum are now known to originate from tubal epithelium. They are of two distinct types, high grade and low grade, which are now recognized as different neoplasms with distinctive features, oncogenesis and behavior. Pseudomyxoma peritonei (PMP) is an unusual condition that usually arises from an appendiceal mucinous neoplasm. Recent consensus in the classification and nomenclature of these lesions is discussed, including the distinction between low grade and high grade appendiceal mucinous neoplasms (HAMN), and the diagnostic criteria for appendiceal adenocarcinoma. PMP is divided into four prognostic groups: acellular mucin, low grade mucinous carcinoma peritonei, high grade mucinous carcinoma peritonei, and high grade mucinous carcinoma peritonei with signet ring cells. The pseudomyxoma microbiome is a promising area for clinical intervention but has been the subject of little research activity. Goblet cell adenocarcinoma (previously known as 'goblet cell carcinoid') is a distinctive type of appendiceal adenocarcinoma. Its behavior correlates with histologic features, but no general consensus for classification has been reached.

Nasogastric- vs. percutaneous gastrostomy tube for prophylactic gastric decompression after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

Objectives

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with postoperative gastroparesis and ileus. In 2015, our practice shifted from using percutaneous gastrostomy tubes (PGT), to nasogastric tubes (NGT) for prophylactic gastric decompression after CRS-HIPEC. This study aimed to compare these methods for length of stay (LOS) and associated complications.

Methods

Patients that underwent CRS-HIPEC for peritoneal metastases from colorectal cancer between 2014 and 2019 were included. Cases were grouped based on receiving NGT or PGT postoperatively. Multivariable linear regression determined the independent effect of decompression method on LOS, thereby adjusting for confounders.

Results

In total, 179 patients were included in the analyses. Median age was 64 years [IQR:54–71]. Altogether, 135 (75.4%) received a NGT and 44 (24.6%) received a PGT. Gastroparesis occurred significantly more often in the PGT group (18.2 vs. 7.4%, p=0.039). Median LOS was significantly shorter for patients with a NGT (15 [IQR:12–19] vs. 18.5 [IQR:17–25.5], p<0.001). PGT was independently associated with longer LOS in multivariable analysis (Beta=4.224 [95%CI 1.243–7.204]). There was no difference regarding aspiration, pneumonia and postoperative mortality between groups.

Conclusions

NGT should be preferred over PGT for gastric decompression after CRS-HIPEC as it is associated with fewer gastroparesis and shorter LOS.

CD31 and D2-40 Contribute to Peritoneal Metastasis of Colorectal Cancer by Promoting Epithelial-Mesenchymal Transition

Background/Aims

Colorectal cancer (CRC) patients often exhibit peritoneal metastasis, which negatively impacts their prognosis. CD31 and D2-40 have recently been suggested to be predictors of breast cancer prognosis, but their role in colorectal peritoneal metastasis (CRPM) remains unknown.

Methods

The expression profiles of CD31 and D2-40 were analyzed in CRC patients with or without CRPM and in CRC cell lines with increasing metastatic potential. Overexpression and short hairpin RNA knockdown assays were performed in CRC cells, and the effects of these alterations on epithelial-mesenchymal transition (EMT) in vitro, growth of xenograft tumors in vivo, and peritoneal metastasis potential in a mouse model of CRPM were examined.

Results

The expressions of CD31 and D2-40 were upregulated in CRC tumor tissues and was elevated further in tumor tissues from patients with CRPM. CD31 and D2-40 expression levels exhibited increasing trends parallel to the EMT potential of CRC cells. CD31 and D2-40 are essential for CRC cell EMT in vitro as well as for xenograft tumor growth and peritoneal metastasis in vivo.

Conclusions

CD31 and D2-40 contribute to CRPM by promoting EMT and may serve as prognostic markers and therapeutic targets for CRC, particularly in patients with peritoneal metastasis.

Intraperitoneal Chemotherapy for Peritoneal Metastases: Technical Innovations, Preclinical and Clinical Advances and Future Perspectives

(1) Background: Tumors of the peritoneal serosa are called peritoneal carcinosis. Their origin may be primary by primitive involvement of the peritoneum (peritoneal pseudomyxoma, peritoneal mesothelioma, etc.). This damage to the peritoneum can also be a consequence of the dissipation of cancers-in particular, digestive (stomach, pancreas, colorectal, appendix) and gynecological (ovaries) ones in the form of metastases. The aim of the treatment is a maximal reduction of the macroscopic disease called "cytoreduction" in combination with hyperthermic intra-abdominal chemotherapy to treat residual microscopic lesions. (2) Methods: In this narrative review, we fundamentally synthetize the evolution of this process over time and its impact on clinical applications. (3) Results: Over the last past decade, different evolutions concerning both delivery modes and conditions concerning hyperthermic intra-abdominal chemotherapy have been realized. (4) Conclusion: The final objective of these evolutions is the improvement of the global and recurrence-free survival of primary and secondary malignant peritoneal pathologies. However, more large randomized controlled trials are needed to demonstrate the efficacy of such treatments with the help of molecular biology and genetics.

Combination of tumor cell anti-adhesion and anti-tumor effect to prevent recurrence after cytoreductive surgery in a mice model

One of the main problems of colorectal cancer is not the treatment of the primary tumor but the metastatic stage. Means of metastatic spread is the invasion of the peritoneal cavity which leads to peritoneal metastasis (PM). PM cannot be easily cured, and the current treatments is rather heavy, combining cytoreductive surgery with intravenous and intraperitoneal chemotherapy. This therapeutic procedure is associated with significant morbidity, altered patient quality of life and poor prognosis. We postulated that development of a prophylactic treatment could be of high interest in this context. In this study, we formulated an anti-adhesive thermogel which contains chemotherapeutics to play a role of a barrier against tumor cells implantation, avoiding their adhesion and treating the remaining tumor cells with chemotherapy intraperitoneally in a mice model of PM. The bioavailability of the thermogel was tested intraperitoneally in mice. No sign of toxicity was observed in terms of change in body weight, anatomopathology and blood biomarkers. In vitro experiments proved that the thermogel induced limited adhesion of the tumor cells. Loading of oxaliplatin (Ox) and 5-Fluorouracil (5-FU) into the thermogel were able to significantly decreased peritoneal carcinomatosis index (PCI) (-58%) and ascites (-70%) in a murine model of peritoneal metastases. These pre-clinical results confirmed that smart thermogel associated with standard chemotherapy 5-FU and Ox could be a good candidate to decrease the risk of tumor cell implantation during cytoreductive surgery and prevent future metastatic process.

Review of systemic chemotherapy in unresectable colorectal peritoneal carcinomatosis

Colorectal cancer remains the third most common malignancy in Australia with the peritoneum being the second most common metastatic site. Colorectal peritoneal carcinomatosis (CPC) can be treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy but this is only limited to a small subset of patients. Those with inoperable disease have a particularly poor prognosis. While the ideal systemic regimen has not been defined, 5-fluorouracil-based chemotherapy regimens appear to provide overall and progression free survival benefits. The role of targeted agents such as bevacizumab (vascular endothelial growth factor inhibitor) or cetuximab (epidermal growth factor inhibitor) in the setting of CPC is still evolving. Currently, retrospective analyses have shown promising results for the use of bevacizumab in addition to systemic chemotherapy but similar results have not been seen with cetuximab or panitumumab. However, there is significant heterogeneity in the trial data, lack of prospective randomized controlled trials and demonstrated treatment variability based on age and tumour characteristics. This review summarises the current literature in regard to treatment in the unresectable CPC setting as well as discussing issues with the current data and highlighting the need for further trials.

Thirty-three long-term survivors after cytoreductive surgery in patients with peritoneal metastases from colorectal cancer: a retrospective descriptive study

BACKGROUND

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival in selected patients with peritoneal metastasis (PM) from colorectal cancer (CRC). However, little has been reported on characteristics and clinical course of long-term survivors with CRC-PM beyond 5 years. The objective of this study was to identify the clinical and oncological features affecting long-term survival of CRC-PM after comprehensive treatment.

METHODS

Between January 1990 and April 2015, CRC-PM patients who underwent CRS with or without HIPEC in two Japanese tertiary hospitals were analyzed. Clinicopathological parameters and therapeutic details for long-term survivors (patients surviving ≥ 5 years after CRS) were described and compared with those for non-survivors (patients surviving < 5 years).

RESULTS

The study identified 236 patients with CRC-PM who underwent CRS, with a median follow-up period of 2.5 years. Thirty-three patients (14.0%) were considered as long-term survivors. Compared with non-survivors, long-term survivors had a lower median peritoneal cancer index (PCI) [4 (1-27) vs 9 (0-39), p < 0.001]. Complete cytoreduction (CCR-0) was achieved in all long-term survivors, with a significantly higher rate [33/33 (100%) vs 141/203 (69.8%), p < 0.001]. Metachronous onsets of PM were more frequently observed in the long-term survivor group [26/33 (78.8%) vs 103/203 (50.3%), p = 0.018]. Regarding histopathology, long-term survivors more frequently had mucinous adenocarcinoma than non-survivors [8/33 (24.2%) vs 27/203 (13.3%)] and less likely exhibited poorly differentiated or signet ring cell carcinoma [2/33 (6.1%) vs 48/203 (23.7%)] (p < 0.001).

CONCLUSIONS

One in seven patients with CRC-PM achieved the long-term milestone after CRS. A long-term survival was associated with the presence of low PCI, CCR-0, metachronous onset, and mucinous histology.

Results of systematic second-look surgery plus hipec in perforated or pt4 colon cancer. Case series

Background

Perforated or pT4 colonic tumors have a bad prognosis with a high rate of relapse, including peritoneal relapse (20–30%). Our aim is to analyze the effectiveness of Second Look surgery (SLS) + hyperthermic intraperitoneal chemotherapy (HIPEC) in these patients for early treatment of peritoneal relapse (PR) or for preventing it.

Patients and methods

Patients previously operated for colon cancer, either pT4 or perforated (M0), with no evidence of disease at any level after adjuvant chemotherapy, who undergo systematic SLS + HIPEC (Oxaliplatin 30 min) one year after the initial surgery.

Results

Since February 2014 to July 2018, we performed SLS + HIPEC in 42 patients with M0, either pT4 (n = 33) or perforated (n = 9) colon cancer. Although during SLS there were suspicious lesions in 15 cases (37.5%), they were histologically confirmed in only 4 (9.5%). Histologically confirmed peritoneal relapse (PR) rate at SLS was 6% in pT4 (2/33) and 22.2% in perforated tumors (2/9). Prophylactic HIPEC was performed in all the cases. There was no postoperative mortality. Grade III-IV morbidity occurred in 19% (8/42). With a median follow-up of 33.8 months after primary tumor surgery, 6/42 patients (14.3%) presented peritoneal relapse (PR). 3-year peritoneal disease free survival was 86%, with 3-year disease free survival of 78.6% and 5-year overall survival (OS) of 97.4%.

Conclusion

Peritoneal relapse and survival rates are remarkable in these groups of, a priori, very bad prognosis, which could suggest a beneficial effect of HIPEC.

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Prospective study trying to decrease peritoneal relapse in perforated or pT4 CRC.

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20–30% of perforated or pT4 CRC develop peritoneal metastases in the follow-up.

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We find peritoneal disease at Second Look surgery before seen in the image tests.

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Second-Look Surgery + HIPEC decreases peritoneal relapse and gets better survival.