Patients will be enrolled after the completion of systemic therapy and after completion of the restaging follow up, which is the time period from 4 weeks to 3 months after discontinuation of the chemotherapy. Once patients are enrolled to extended interval PAC flushes, they will be followed for one year. At the end of the year patients will return to standard PAC flushes. If patients experience any PAC malfunction, it would be considered a PAC failure and the flushing will reverted back to the schedule recommended by the manufacturer.