Pressurized intraperitoneal aerosol chemotherapy with oxaliplatin (PIPAC-OX) in patients with colorectal peritoneal metastases: a systematic review

Pressurized intraperitoneal aerosol chemotherapy with oxaliplatin (PIPAC-OX) is increasingly used as a palliative treatment option for patients with colorectal peritoneal metastases (CPM). The present study aimed to systematically review all clinical studies reporting safety and efficacy outcomes of PIPAC-OX in patients with CPM. PubMed, EMBASE, The Cochrane Library, and CINAHL were systematically searched to identify all clinical studies that included at least one patient with CPM treated with PIPAC-OX and reported one of the following outcomes: Adverse events, tumor response, quality of life, secondary cytoreductive surgery, progression-free survival, overall survival, and environmental safety of PIPAC-OX. Results were narratively described. Of 28 included studies, only 14 non-comparative studies separately reported at least one outcome of PIPAC-OX for CPM, of which only two studies specifically focused on this group. These 14 studies reported adverse events (5 studies), tumor response (5 studies), secondary cytoreductive surgery (4 studies), progression-free survival (1 study), overall survival (5 studies), and environmental safety (2 studies). Except for 5 studies (describing 26 patients), none of the included studies stratified their results for PIPAC-OX monotherapy and PIPAC-OX with concomitant systemic therapy, and none of the studies reporting survival outcomes stratified results for line of palliative treatment, complicating interpretation. No PIPAC-OX related deaths were reported. No occupational platinum was detected during PIPAC-OX. The available evidence regarding PIPAC-OX for CPM is limited and difficult to interpret. Despite these limitations, PIPAC-OX appears safe in patients with CPM and safe for operating personnel. To increase insight in the role of PIPAC-OX in this setting, investigators of ongoing and future studies are encouraged to report separate outcomes of PIPAC-OX for CPM, to stratify their results for PIPAC-OX monotherapy and PIPAC-OX with concomitant systemic therapy, and to stratify survival results for line of palliative treatment.