Radiopharmaceutical Oncology Care Supported by Ultrasound-Guided Superior Vena Cava-Right Atrial Junction Port Tip Positioning in Adult Cancer Patients

Abstract

Background:

In this single-center retrospective study, the authors evaluated whether real-time ultrasound-guided positioning of an implantable venous access port catheter tip at the superior vena cava-right atrial junction (SVC-RAJ) reduces the risk of catheter-related thrombosis (CRT) in adult patients with cancer and developed a multivariable risk prediction model to support individualized prevention.

Methods:

Clinical data from 600 consecutive patients who underwent port implantation at Zhongshan People’s Hospital were analyzed. Patients were grouped according to final catheter tip position (SVC-RAJ versus non-SVC-RAJ), and CRT incidence was compared between groups.

Results:

The overall incidence of CRT was 30.33% (182/600) and was significantly lower in the SVC-RAJ group than in the non-SVC-RAJ group (22.42% vs. 38.73%, p < 0.001). In multivariable analysis, catheter tip positioning at the SVC-RAJ remained an independent protective factor (odds ratio = 0.517, 95% confidence interval [CI]: 0.353–0.756). Age, body mass index (BMI), tumor stage, neutrophil-to-lymphocyte ratio, D-dimer level, catheterization duration, and prophylactic anticoagulation status were also independently associated with CRT. A nomogram integrating these variables demonstrated good discrimination (area under the curve = 0.866, 95% CI: 0.837–0.895), with a sensitivity of 70.33% and a specificity of 85.89%. Performance across specific age or BMI strata was not separately evaluated in this study, and further stratified validation in larger datasets is needed to assess model consistency across demographic subgroups.

Conclusions:

These findings support ultrasound-guided SVC-RAJ positioning as a clinically relevant strategy for reducing CRT risk and maintaining reliable venous access in contemporary oncology care pathways.