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

Purpose: We aimed to determine the value of laparoscopy to assess the intra-abdominal tumor extent and predict complete cytoreduction. Methods: All patients at our department in the period from 2017 to 2021 that underwent laparoscopy to assess peritoneal metastasis and subsequent open exploration with the intention to perform cytoreductive surgery (CRS) with HIPEC were retrospectively identified in a continuously maintained database. Results: Forty-three patients were analyzed. Peritoneal cancer index (PCI) determination by laparoscopy compared to open surgery was overestimated in five patients (11.6%), identical in eleven patients (25.6%), and underestimated in 27 patients (62.8%). PCI differences were independent of surgeons, tumor entities, and prior chemotherapy. Thirty-four patients (79.1%) were determined eligible for CRS with HIPEC during open exploration, whereas nine patients (20.9%) underwent a non-therapeutic laparotomy. Complete or almost complete cytoreduction was achieved in 33 patients (76.7%). In one patient, completeness of cytoreduction was not documented. Conclusions: We demonstrate a moderate agreement according to weighted Cohen’s kappa analysis of PCI values calculated during laparoscopy and subsequent open exploration for CRS with HIPEC. Uncertainty of PCI assessment should therefore be kept in mind when performing laparoscopy in patients with peritoneal metastasis.

Oncolytic virotherapy with measles vaccine virus (MeV) already has been demonstrated to be safe. However, early clinical results pointed out the necessity for an enhancement of oncolytic effectiveness of MeV-based virotherapeutics. In our work, we are developing an armed measles vaccine virus (MeV-SCD) encoding a suicide fusion gene of yeast cytosine deaminase/uracil phosphoribosyltransferase, converting the nontoxic prodrug 5-fluorocytosine (5-FC) to the chemotherapeutic drug 5-fluorouracil (5-FU). To preclinically investigate what an optimal prodrug-assisted therapeutic regimen might look like, we added 5-FC at various time points after infection with MeV-SCD and either let the prodrug remain in the tumor cell culture medium continuously for various time periods (“continuous” 5-FC application) or applied it only temporarily for defined shorter periods of time (“pulsed” 5-FC application); we also varied the time point at which 5-FC was added after infection with MeV-SCD. As a result, addition of the prodrug at early times postinfection (e.g., at 3 hr postinfection) was found to be inferior concerning the overall oncolytic effectiveness when compared with addition of 5-FC at later time points (e.g., at 24 hr postinfection). Next, oncolytic effectiveness was found to correlate positively with the overall duration of incubation of MeV-infected tumor cells with 5-FC. Of note, this was true despite our finding that addition of the prodrug could also exert an inhibitory effect on the generation of infectious progeny viral particles, that is, on virus replication. These findings should be helpful for the rational design of further trials (preclinical, clinical) using suicide gene armed virotherapeutics, such as MeV-SCD.

Background: Pancreatic ductal adenocarcinoma (PDAC) is a common fatal disease with unfavorable prognosis, even after oncological resection. To improve survival, adding hyperthermic intraperitoneal chemotherapy (HIPEC) has been suggested. Whether HIPEC entails disproportional short-term mortality is unknown and a prospectively determined adverse events profile is lacking. Since both pancreatic resection and HIPEC may relevantly influence morbidity and mortality, this uncontrolled single-arm, open-label, phase I/II pilot trial was designed to assess the 30-day mortality rate, treatment feasibility, and adverse events connected with HIPEC after oncological pancreatic surgery. Methods: This trial recruited patients scheduled for PDAC resection. A sample size of 16 patients receiving study interventions was estimated to establish a predefined margin of treatment-associated short-term mortality with a power of > 80%. Patients achieving complete macroscopic resection received HIPEC with gemcitabine administered at 1000 mg/m² body surface area heated to 42 °C for 1 hour. Results: Within 30 days after intervention, no patient died or experienced any adverse events higher than grade 3 that were related to HIPEC. Furthermore, treatment-related adverse events were prospectively documented and categorized as expected or unexpected. This trial supports that the actual mortality rate after PDAC resection and HIPEC is below 10%. HIPEC treatment proved feasible in 89% of patients allocated to intervention. Pancreatic fistulas, as key complications after pancreas surgery, occurred in 3/13 patients under risk. Conclusion: Combined pancreas resection and gemcitabine HIPEC proved feasible and safe, with acceptable morbidity and mortality. Based on these results, further clinical evaluation can be justified. Registration Number: NCT02863471 (http://www.clinicaltrials.gov).

Background: Extralevator abdominoperineal excision (ELAPE) is a relatively new surgical technique for low rectal cancers, enabling a more radical approach than conventional abdominoperineal excision (APE) with a potentially better oncological outcome. To date, no standard exists for reconstruction after extended or extralevator approaches of abdominoperineal (ELAPE) resection for lower gastrointestinal cancer or inflammatory tumors. In the recent literature, techniques with myocutaneous flaps, such as the VY gluteal flap, the pedicled gracilis flap, or the pedicled rectus abdominis flaps (VRAM) are primarily described. We propose a tailored concept with the use of bilateral adipo-fasciocutaneous inferior gluteal artery perforator (IGAP) advancement flaps in VY fashion after ELAPE surgery procedures. This retrospective cohort study analyzes the feasibility of this concept and is, to our knowledge, one of the largest published series of IGAP flaps in the context of primary closure after ELAPE procedures. Methods: In a retrospective cohort analysis, we evaluated all the consecutive patients with rectal resections from Jan 2017 to Sep 2021. All the patients with abdominoperineal resection were included in the study evaluation. The primary endpoint of the study was the proportion of plastic reconstruction and inpatient discharge. Results: Out of a total of 560 patients with rectal resections, 101 consecutive patients with ELAPE met the inclusion criteria and were included in the study evaluation. The primary direct defect closure was performed in 72 patients (71.3%). In 29 patients (28.7%), the defect was closed with primary unilateral or bilateral IGAP flaps in VY fashion. The patients’ mean age was 59.4 years with a range of 25–85 years. In 84 patients, the indication of the operation was lower rectal cancer or anal cancer recurrence, and non-oncological resections were performed in 17 patients. Surgery was performed in a minimally invasive abdominal approach in combination with open perineal extralevatoric abdominoperineal resection (ELAPE) and immediate IGAP flap reconstruction. The rate of perineal early complications after plastic reconstruction was 19.0%, which needed local revision due to local infection. All these interventions were conducted under general anesthesia (Clavien–Dindo IIIb). The mean length of the hospital stay was 14.4 days after ELAPE, ranging from 3 to 53 days. Conclusions: Since radical resection with a broad margin is the standard choice in primary, sphincter-infiltrating rectal cancer and recurrent anal cancer surgery in combination with ELAPE, the choice technique for pelvic floor reconstruction is under debate and there is no consensus. Using IGAP flaps is a reliable, technical, easy, and safe option, especially in wider defects on the pelvic floor with minimal donor site morbidity and an acceptable complication (no flap necrosis) rate. The data for hernia incidence in the long term are not known.