2603 - Clinical Characteristics of Catheter-Related Thrombosis in Caprini-Stratified Moderate/High-Risk Lung Cancer Patients with PICC: A Preliminary Clinical Observation

Purpose/Objective(s): Peripherally Inserted Central Catheter (PICC)-related thrombosis (CRT) remains a critical complication in lung cancer patients undergoing radiotherapy. While the Caprini Risk Assessment Model is established for venous thromboembolism stratification, the clinical characteristics and outcomes of CRT in moderate-to-high-risk patients managed with standard catheter locking regimens are not well elucidated. This study aims to establish baseline data on CRT incidence, coagulation dynamics, and safety in Caprini-stratified patients to justify optimized individual prophylaxis.

Materials/Methods: A quasi-experimental, non-concurrent controlled study was conducted involving eligible lung cancer patients with PICCs admitted to the Radiation Oncology center from October 2025 to January 2026. Patients were stratified via the Caprini scale into a Moderate-Risk group (score 3-4) receiving pulsed saline locking, and a High-Risk group (score =5) receiving 5 U/mL heparin sodium locking. Primary endpoints included CRT incidence (confirmed by blinded ultrasonography and symptoms) and coagulation markers (D-dimer, fibrinogen) monitored at 2 weeks, 1 month, and catheter removal. Safety outcomes included catheter patency and bleeding events.

Results: A total of 29 patients (20 Moderate-Risk; 9 High-Risk) completed the study. The incidence of CRT was substantial in both groups: 20.0% (4/20) in the Moderate-Risk group and 22.2% (2/9) in the High-Risk group, with no significant difference observed. Thromboses were predominantly located in the basilic, subclavian, and axillary veins. Patients developing CRT exhibited characteristic spikes in D-dimer (1.2–8.9 times baseline) and fibrinogen (0.8–2.1 times baseline). Regarding safety, no locking-related bleeding events occurred, and no abnormal flushing resistance was noted, despite varying degrees of blood reflux.

Conclusion: Lung cancer patients stratified as moderate-to-high risk by the Caprini scale exhibit a high incidence of CRT despite conventional locking with saline or low-dose heparin. While these standard regimens pose no bleeding risk, they appear suboptimal for thrombosis prevention in this specific population. These findings provide critical baseline evidence supporting the need for differentiated strategies, such as higher-concentration heparin (10 U/mL), which will be evaluated in the subsequent phase of this study.