Catheter — Flexible Medical Tube

In oncology, a catheter is a medical device engineered from flexible materials such as silicone, polyurethane, or latex. It can be inserted into blood vessels, cavities, or organs depending on clinical need. Vascular catheters provide reliable access to the circulatory system, enabling the administration of chemotherapy, immunotherapy, blood products, and intravenous hydration without damaging peripheral veins.

Non-vascular catheters serve drainage and diagnostic purposes. For instance, urinary catheters drain the bladder during pelvic surgery or treatment-related urinary retention. Other drainage catheters may be positioned in the pleural or peritoneal spaces to manage malignant fluid accumulation, improving comfort and supporting continuous clinical assessment.

Catheters significantly improve comfort and treatment reliability. Many cancer therapies, particularly vesicant chemotherapy agents, can irritate small arm veins if given through a standard cannula. Catheters protect vein health and ensure drugs reach the circulation safely. They also facilitate continuous home infusions, allowing individuals to maintain everyday routines outside the hospital. Proper management of a catheter is vital, as careful maintenance prevents complications like blockages or bloodstream infections, keeping your therapy schedule on track.

A catheter is not a biological marker, so it is not evaluated via lab assays. However, objective tests guide its placement and maintenance. Imaging modalities such as ultrasound, fluoroscopy, or chest X-rays verify correct positioning before use. Laboratory monitoring includes complete blood counts to check infection risk, coagulation profiles to ensure safe insertion, and blood or fluid cultures if an infection is suspected at the catheter site.

Catheters are utilised across almost all oncology settings. They are particularly common in haematological malignancies such as leukaemia, lymphoma, and multiple myeloma, where intensive, multi-agent chemotherapy regimens are frequent. They are also standard in gastrointestinal cancers, such as colorectal or pancreatic cancer, which often require continuous infusions via portable pumps. Urinary and drainage catheters frequently assist individuals receiving treatment for bladder, prostate, ovarian, or advanced lung cancers.

Catheters are integral to delivering systemic therapies. They allow the safe infusion of vesicant chemotherapies, monoclonal antibodies, parenteral nutrition, and supportive anti-nausea medications. They also connect to ambulatory pumps for outpatient infusions, such as 46-hour fluorouracil regimens. Drainage catheters alleviate symptoms caused by malignant ascites or pleural effusions, restoring breathing comfort and mobility so patients remain fit enough to continue active cancer therapies.