Chemotherapy is an essential component of breast cancer treatment. Frequent intravenous injections may lead to phlebitis and limited venous access, therefore implantable venous ports are increasingly used. The choice of port placement side in breast cancer patients is controversial, especially when mastectomy or radiotherapy is planned. This retrospective cohort study compares one-year patency, complications (infection, thrombosis, skin necrosis), and functional outcomes of ports implanted via the right internal jugular vein in patients with right versus left breast cancer.

Breast cancer is the most common malignancy among women worldwide. Chemotherapy remains a cornerstone of treatment, whether in neoadjuvant or adjuvant settings. Despite advancements in drug formulations, repeated intravenous injections frequently result in phlebitis and loss of venous access. As a result, many patients and physicians prefer the use of totally implantable venous access devices (ports). These devices consist of a catheter and a chamber, allowing direct administration of chemotherapy into a central vein, reducing endothelial damage.

However, ports carry risks including infection, venous thrombosis, skin necrosis, and mechanical failure. In breast cancer patients who undergo mastectomy or radiotherapy, the optimal side for port implantation is controversial. Some surgeons avoid the ipsilateral side due to concerns about complications, while others report no additional risk when proper technique is used.

This retrospective cohort study evaluates the patency and safety of ports implanted through the right internal jugular vein in patients with right- and left-sided breast cancer treated in Gorgan medical centers between 2017 and 2024. Patient records will be reviewed to collect demographic information, tumor laterality, type of breast surgery (mastectomy vs. breast-conserving surgery), use of radiotherapy, type of port, and follow-up outcomes. Complications including infection, thrombosis, and skin necrosis will be recorded. The primary endpoint is one-year port patency; secondary endpoints include complication rates and associations with clinical variables such as age, stage, smoking status, and prior radiotherapy.

This study aims to clarify whether the side of breast cancer affects the outcomes of right internal jugular port implantation, and to provide evidence to guide decision-making regarding optimal port placement in breast cancer patients requiring chemotherapy.

Inclusion Criteria:

• Female patients with breast cancer (right or left side)
• Underwent chemotherapy port implantation via right internal jugular vein between 2017-2024 in Gorgan medical centers

Exclusion Criteria:

• Prior neck surgery or radiotherapy involving right jugular area
• Incomplete medical records

All breast cancer patients receiving right internal jugular venous port implantation in Gorgan medical centers (2017-2024).

The individual participant data will not be shared because of patient privacy concerns and institutional policies.