Anaesthesia in a Toxic Environment: Pressurised Intraperitoneal Aerosol Chemotherapy: A Retrospective Analysis

Consensus statement on safety measures for pressurized intraperitoneal aerosol chemotherapy

Objectives

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a promising treatment for peritoneal cancer that entails, however, potential risks for the caregivers in the operating room (OR). This study aimed to reach a consensus within the PIPAC community on a comprehensive safety protocol.

Methods

Active PIPAC centers were invited to participate in a two-round Delphi process on 43 predefined items: concise summaries of the existing evidence were presented together with questions formulated using the population, intervention, comparator, and outcome framework. According to the Grading of Recommendations Assessment, Development, and Evaluation, the strength of recommendation was voted by panelists, accepting a consensus threshold of ≥50% of the agreement for any of the four grading options, or ≥70% in either direction.

Results

Forty-seven out of 66 invited panelists answered both rounds (response rate 76%). The consensus was reached for 41 out of 43 items (95.3%). Strong and weak recommendations were issued for 30 and 10 items, respectively. A positive consensual recommendation was issued to activate laminar airflow without specific strength, neither strong nor weak. No consensus was reached for systematic glove change for caregivers with a high risk of exposure and filtering facepiece mask class 3 for caregivers with low risk of exposure.

Conclusions

A high degree of consensus was reached for a comprehensive safety protocol for PIPAC, adapted to the risk of exposure for the different caregivers in the OR. This consensus can serve as a basis for education and help reach a high degree of adherence in daily practice.

Histological regression of gastrointestinal peritoneal metastases after systemic chemotherapy

Objectives

Peritoneal metastases (PM) are relatively resistant to systemic chemotherapy, and data on histological response to therapy is rare. The aim of this study was to quantify the treatment response of PM after systemic chemotherapy.

Methods

Retrospective monocentric cohort study of 47 consecutive patients with PM from gastrointestinal origin undergoing surgery (cytoreduction: CRS + Hyperthermic IntraPEritoneal Chemotherapy [HIPEC] or Pressurized IntraPeritoneal Aerosol Chemotherapy [PIPAC]) after prior systemic chemotherapy from 1.2015 to 3.2019. Tumor response was assessed using the 4-scale Peritoneal Regression Grading System (PRGS) (4: vital tumor to 1: complete response).

Results

Patients had a median of 2 (range: 1-7) lines and 10 (3-39) cycles of prior systemic chemotherapy. A median of four biopsies (range: 3-8) was taken with a total of 196 analyzed specimens. Twenty-four biopsies (12%) showed no histological regression (PRGS4), while PRGS 3, two and one were diagnosed in 37 (19%), 39 (20%), and 69 (49%) specimens, respectively. A significant heterogeneity was found between peritoneal biopsies in 51% patients. PRGS correlated strongly with peritoneal spread (PCI, p<0.0001), and was improved in patients with more than nine cycles of systemic chemotherapy (p=0.04). Median survival was higher in patients with PRGS < 1.8 (Quartiles one and 2) than higher (Q3 and Q4), but the difference did not reach significance in this small cohort.

Conclusions

PRGS is an objective too to describe histological response of PM of GI origin after systemic chemotherapy. This response differs significantly between patients, allowing to distinguish between chemosensitive and chemoresistant tumors.