Band 10, Heft 2

There is growing interest in the role of the microbiome in carcinogenesis, but few studies examine the microbiome of pseudomyxoma peritonei (PMP). This scoping review summarises the microorganisms identified in PMP samples and examines the evidence of their role in disease outcomes. The methodology was developed in accordance with the PRISMA-ScR framework and checklist. Nine relevant studies were included. Microbiological testing was performed on PMP samples from 85 patients. At the phylum level, Proteobacteria was detected in greatest relative abundance in tumour tissue, cellular and acellular mucin. The relative proportion of different phyla more closely resembled the gut microbiome in inflammatory bowel disease than in a healthy gut. High-grade specimens showed significantly higher bacterial density than low-grade specimens and non-neoplastic non-perforated appendix specimens. Survival data of 58 patients were published, correlating outcomes to pre-operative antibiotic administration. Observed differences were not statistically significant. There is evidence of an altered bacterial profile in PMP samples compared to a healthy gut microbiome, the significance of which is unclear. Significant methodological challenges remain in this field of study. This scoping review supports the need for further analysis of the PMP bacterial profile, using methodologies that incorporate controls and deliver taxonomic resolution at species level.

Objectives This study aims to evaluate the clinical impact of introducing an Enhanced Recovery After Surgery (ERAS) protocol in the management of patients undergoing cytoreductive surgery (CRS), with or without hyperthermic intraperitoneal chemotherapy (HIPEC). By addressing a population at high risk of postoperative complications and delayed recovery, the study seeks to determine whether ERAS can improve short-term outcomes, optimize perioperative care, and promote faster and safer recovery in a standardized, evidence-based manner across multiple centers. Methods The EPICH study is a multicenter, prospective, interventional trial conducted across 20 centers in Italy. A total of 300 patients undergoing CRS±HIPEC will be enrolled in two sequential phases: standard perioperative care followed by ERAS protocol implementation. The primary endpoint is the mean hospital length of stay (LOS). Secondary endpoints include postoperative complications, ICU admission, readmission rates, bowel function recovery, mortality, and patient-reported quality of recovery. The ERAS protocol includes prehabilitation, anemia and nutritional optimization, intraoperative fluid and pain management, and early mobilization and oral feeding. Data will be analyzed using random-effects linear models to account for center-level variation and confounding factors. Results Preliminary evidence suggests that the ERAS protocol may help reduce mean hospital LOS, postoperative complications, and ICU stays, as well as support faster bowel recovery and improved patient-reported outcomes—findings that this study seeks to validate. Conclusions The EPICH study could provide robust evidence supporting the adoption of ERAS as the standard of care for patients undergoing CRS±HIPEC, with potential benefits in terms of improved recovery, reduced complications, and decreased healthcare resource utilization.

Objectives Surgical staging procedures are used to select patients with peritoneal metastases for surgery. We aimed to evaluate the impact of surgical staging procedures and the risk of abdominal wall recurrences in patients with peritoneal metastases scheduled for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). Methods Data were collected from a prospective maintained HIPEC register January 2012–December 2019. Patients with colorectal peritoneal metastases were included. Information about surgical staging procedures was registered. Results were then compared with those registered at definite CRS-HIPEC surgery and survival was analysed in relation to surgical staging procedures. Results In total, 138 patients were included, of whom 32 had undergone a surgical staging procedure before CRS-HIPEC. Median overall survival in the surgical staging group was 1.89 years and in the non-staging group 3.07 years (p=0.060). In the surgical staging group, eight patients developed abdominal wall recurrences (25 %) compared with three (3 %) in the non-staged group. Eight staged patients (25 %) were considered inoperable at definite surgery (open-close). PCI score (p<0.001) was higher at definite surgery in patients who had undergone a staging laparoscopy. Factors associated with shorter overall survival in multivariate analysis were: open and close, PCI ≥21 and presence of signet ring cells. However, a staging procedure was not associated with a shorter overall survival. Conclusions Surgical staging procedures is a valuable assessment of inoperability, though at the expense of more frequent abdominal wall recurrences. Imaging-based strategies may provide useful insights into whether surgical staging is the most effective approach for patient selection.

Objectives This explorative porcine study investigated the immediate postoperative response of inflammatory protein markers and ischemic metabolites in peritoneal abdominal wall tissue during and after hyperthermic intraperitoneal chemotherapy (HIPEC) assessed by microdialysis. Methods Eight cancer-free female pigs underwent imitation cytoreductive surgery (CRS) followed by HIPEC (90 min) using a carboplatin dosage of 800 mg/m 2 . A subperitoneal microdialysis catheter was placed in the abdominal wall to sample inflammatory protein markers and ischemic metabolites. During and after HIPEC, dialysates and blood samples were collected over 8 h. Inflammatory protein expression levels were quantified using Proximity Extension Assay (Olink Target 96 Inflammation panel). In addition, concentrations of ischemic metabolites were quantified using a CMA600 microdialysis analyzer. Results An immediate response of 27 proteins, including proteins from the TNF family, early inflammatory chemokines, pro- and anti-inflammatory proteins, was found within the first 30 min after HIPEC initiation. This was followed by a modest and relatively constant inflammatory response. Glycerol concentrations tended to decrease during the sampling period, while glucose showed more stable levels. Constant hyperlactatemia exceeding the plasma levels was seen during and after HIPEC, with no significant tissue ischemia as indicated by the lactate/pyruvate ratios. Conclusions In a porcine model, CRS with HIPEC leads to an immediate and relatively constant increased inflammatory and ischemic peritoneal tissue short-time response. The explorative findings contribute to the debate on the value of HIPEC in combination with CRS and call for future studies to further investigate the inflammatory and metabolic tissue responses.

Objectives Synchronous peritoneal metastasis (PM) represents an advanced stage of colorectal cancer (CRC), indicating extensive tumor spread. Visceral adipose tissue (VAT) has been linked to cancer development and progression. This study aims to explore the relationship between VAT and occult synchronous PM in CRC patients before surgery. Methods We enrolled 681 CRC patients, with 419 in the primary cohort (356 non-metastatic and 63 with PM) and 262 in the validation cohort (239 non-metastatic and 23 with PM). Clinical characteristics and laboratory measurements were collected prior to surgery. Adipose and muscle tissues were delineated on preoperative contrast-enhanced computed tomography (CT) images. The association between visceral adipose tissue and synchronous PM was assessed using univariate and multivariate logistic regression analyses. Results In the primary cohort, 419 patients were diagnosed with CRC, with 63 presenting with PM. Patients with PM had higher visceral adipose tissue index (VATI) levels compared to those without PM. Additionally, there was a trend towards increased PM incidence with elevated VATI. Multivariate logistic regression analysis confirmed that higher VATI was independently associated with PM. These findings were consistent in the validation cohort. Conclusions VATI is an independent risk factor for occult synchronous PM in patients with CRC.

Objectives To evaluate the implementation, compliance, and impact of the enhanced recovery after surgery (ERAS) protocol on perioperative outcomes in patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for Stage IIIc ovarian cancer. Methods From September 2020 to March 2022, the ERAS protocol (62 perioperative and special consideration guidelines) was prospectively implemented in 75 patients. Based on compliance rates, patients were divided into three groups: Group A (<70 %, 13 patients), Group B (70 %–80 %, 52 patients), and Group C (>80 %, 10 patients). Compliance rates, length of stay, postoperative complications, and readmission rates were analyzed. Ethical committee approval was obtained. Results The cohort’s average compliance was 74.5 %, with group averages of 68.4 %, 74.4 %, and 82.5 % (p<0.001). Tolerance to normal diet (p=0.008), postoperative ileus (p=0.161), and mobilization rates (p<0.001) improved with higher compliance. Higher compliance also led to shorter hospital stays (p=0.008) and ICU stays (p<0.001). Complications like ileus and infections were lowest in Group C. No significant differences were found in re-surgery or mortality. Conclusions Implementation of the ERAS protocol in patients undergoing CRS and HIPEC for Stage IIIc ovarian cancer is feasible and associated with improved postoperative outcomes. Higher compliance with ERAS guidelines significantly reduced length of hospital and ICU stay, enhanced early mobilization, and improved tolerance to diet, while also decreasing postoperative complications. Compliance above 80 % is necessary for achieving optimal outcomes and protocol modifications may improve compliance.