Incidence of leukopenia after intraperitoneal vs combined intravenous/intraperitoneal chemotherapy in pseudomyxoma peritonei.

Aim: To investigate the clinical impact of post-hyperthermic intraperitoneal chemotherapy (HIPEC) leukopenia, intraperitoneal and combined intravenous/intraperitoneal drug administrations were compared.

Methods: Two patient cohorts were retrospectively analyzed regarding the incidence of postoperative leukopenia. The first cohort (n = 32) received Mitomycin C (MMC)-based HIPEC intraperitoneally (35 mg/m² for 90 min) and the second cohort (n = 10) received a bi-directional therapy consisting of oxaliplatin (OX) (300 mg/m(2) for 30 min) intraperitoneally and 5-fluorouracil (5-FU) 400 mg/m² plus folinic acid 20 mg/m² intravenously. The following data were collected retrospectively: Age, sex, length of operation, length of hospital stay, amount of resection including extent of peritonectomy, peritoneal cancer index, CC (completeness of cytoreduction)-status and leukocyte-count before cytoreductive surgery (CRS) and HIPEC, on days 3, 7 and 14 after CRS and HIPEC. HIPEC leukopenia was defined as < 4000 cells/m³.

Results: Leukopenia occurred statistically more often in the MMC than in the OX/5-FU-group (10/32 vs 0/10; P = 0.042). Leukopenia set-on was on day 7 after CRS and MMC-HIPEC and lasted for two to three days. Three patients (33%) required medical treatment. Patients affected by leukopenia were predominantly female (7/10 patients) and older than 50 years (8/10 patients). The length of hospital stay tended to be higher in the MMC-group without reaching statistical significance (22.5 ± 11 vs 16.5 ± 3.5 d). Length of operation (08:54 ± 01:44 vs 09:48 ± 02:28 h) were comparable between patients with and without postoperative leukopenia. Prior history of systemic chemotherapy did not trigger post-HIPEC leukopenia. Occurrence of leucopenia did not trigger surgical site infections, intraabdominal abscess formations, hospital-acquired pneumonia or anastomotic insufficiencies.

Conclusion: Surgeons must be aware that there is a higher incidence of postoperative leukopenia in MMC-based HIPEC protocols primarily affecting females and older patients.