Safety and feasibility of 3-month interval access and flushing for maintenance of totally implantable central venous port system in colorectal cancer patients after completion of curative intended treatments.

Patients with colorectal cancer (CRC) treated with curative intent surgery undergo continuous fluorouracil (5-FU) infusion-based chemotherapy using totally implantable central venous port system (TICVPS) in cases with high risk of recurrence. Approximately 30% of patients relapse after therapy completion, especially within 2 years. Hence, many patients with high risk CRC keep the TICVPS for 6 to 24 months after treatment with regular intervals of TICVPS flushing. However, little is known about the proper interval duration of the port. The aim of this study is to investigate whether a 3 months extended interval is safe and if port maintenance is feasible.A retrospective cohort was compiled of patients with CRC who underwent curative intent surgery and perioperative chemotherapy using TICVPS between 2010 and 2017. The primary end point was TICVPS maintenance rate, including maintenance of TICVPS for at least 6 months, planned TICVPS removal after 6 months, and regaining the use of TICVPS at the time of recurrence.A total of 214 patients with CRC underwent curative intent treatments during the study period. Among them, 60 patients were excluded, including 6 patients for early recurrence within 3 months and 54 patients with violation of flushing interval. Finally, 154 patients were analyzed. Mean flushing interval was 98.4 days (95% confidence interval [CI], 96.2-100.6; range, 60-120). In December 2018, 35 patients kept the TICVPS, 92 patients had planned removal, 25 patients reused the TICVPS, and 2 patients had to unexpectedly remove the TICVPS due to site infection and pain. Thus, the functional TICVPS maintenance rate was 98.8% (152/154). Thirty-eight patients relapsed, and 30 patients were treated with intravenous chemotherapy. Among them, 25 patients (83.3%) reused the maintained TICVPS without a reinsertion procedures.Our study demonstrated that 3-month interval access and flushing is safe and feasible for maintaining TICVPS during surveillance of patients with CRC. An extended interval up to 3 months can be considered because it is compatible with CRC surveillance visit schedules.