What is long-term survival in patients with peritoneal metastasis from gastric, pancreatic, or colorectal cancer? A study of patients treated with systemic chemotherapy and pressurized intraperitoneal aerosol chemotherapy (PIPAC)

Charlotte G Kryh-Jensen; Claus W Fristrup; Alan P Ainsworth; Sönke Detlefsen; Michael B Mortensen; Per Pfeiffer; Line S Tarpgaard; Martin Graversen

doi:10.1515/pp-2023-0038

What is long-term survival in patients with peritoneal metastasis from gastric, pancreatic, or colorectal cancer? A study of patients treated with systemic chemotherapy and pressurized intraperitoneal aerosol chemotherapy (PIPAC)

Pleura Peritoneum. 2023 Dec 14;8(4):147-155. doi: 10.1515/pp-2023-0038. eCollection 2023 Dec.

Authors

Charlotte G Kryh-Jensen^{1

2}, Claus W Fristrup^{1

2}, Alan P Ainsworth^{1

2}, Sönke Detlefsen^{1

3

4}, Michael B Mortensen^{1

2

4}, Per Pfeiffer^{1

4

5}, Line S Tarpgaard^{1

4

5}, Martin Graversen^{1

2

4

6}

Affiliations

¹ Odense PIPAC Center (OPC), Odense University Hospital, Odense, Denmark.
² Upper GI & HPB Section, Department of Surgery, Odense University Hospital, Odense, Denmark.
³ Department of Pathology, Odense University Hospital, Odense, Denmark.
⁴ Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark.
⁵ Department of Oncology, Odense University Hospital, Odense, Denmark.
⁶ OPEN - Odense Patient Data Explorative Network, Odense University Hospital, Region of Southern Denmark, Odense, Denmark.

Abstract

Objectives: A definition of long-term survival (LTS) in patients with peritoneal metastasis (PM) from gastric cancer (GC), pancreatic cancer (PC) or colorectal cancer (CRC) treated with systemic chemotherapy and pressurized intraperitoneal aerosol chemotherapy (PIPAC) is lacking. We aimed to define LTS and investigate characteristics and treatment response in patients who reached LTS in data from two prospective trials.

Methods: Retrospective study of patients with GC-, PC-, or CRC-PM from the prospective PIPAC-OPC1 and PIPAC-OPC2 studies. The definition of LTS was based on published systematic reviews and randomized controlled trials. LTS was defined at the time point where 25 % of the patients were alive in these studies. Histology based response was evaluated by the mean Peritoneal Regression Grading Score (PRGS) using biopsies obtained prior to PIPAC 3, and defined by a mean PRGS of ≤2.0 or a decrease of mean PRGS of ≥1, compared to baseline.

Results: LTS was defined at 21 (GC), 15 (PC), and 24 (CRC) months. Fifty-one (47.2 %) patients (nine GC, 17 PC, 25 CRC) reached LTS calculated from the date of PM diagnosis. All but one received palliative chemotherapy before PIPAC, and 37 % received bidirectional treatment. More than 90 % of the LTS patients had response according to PRGS. The mOS from PIPAC 1 was 23.3, 12.4, and 28.5 months for GC, PC, and CRC LTS patients.

Conclusions: Patients with PM from GC, PC, and CRC treated with systemic chemotherapy and PIPAC can reach LTS and most show histological response. Causality must be further investigated.

Keywords: PIPAC; PRGS; long-term survival; peritoneal metastasis; response evaluation.