Effects of peripherally inserted central catheter on dosimetry of the blood vessel region in volumetric modulated arc therapy planning for lung cancer

Abstract

Abstract Objective A peripherally inserted central catheter (PICC) is a safe and effective drug delivery method of chemoradiotherapy for lung cancer. However, the risk of vascular damage to patients who require PICC implantation during radiotherapy may be increased. This study compared dosimetry differences in the blood vessel region, as well as the planning target volume and other organs at risk between two volumetric modulated arc therapy plans with and without a PICC for lung cancer. The aim of which was to provide guidance for clinicians to select the proper PICC implantation time. Methods A total of 10 male patients with PICCs who received chemoradiotherapy for lung cancer in Cancer Hospital Chinese Academy of Medical Sciences, Shenzhen Center between 1 January 2019 and 30 November 2019 were included. The prescription dose was 50 Gy in 25 fractions. Two volumetric modulated arc therapy plans, with and without a PICC, were designed for each selected patient on a Varian Eclipse 13.6™ planning system. Statistical analysis of the blood vessel dose distribution of the PICC region and the target dose distribution, including the homogeneity index and conformity index, as well as irradiation doses to the lungs, heart, esophagus, and spinal cord, was carried out for the two groups and the differences were compared. Results When comparing the two plans, the mean dose (Dmean) of the PICC region for the plan with PICC was lower than that for the plan without(P = 0.01). The conformity index of the target, the maximum dose (Dmax) and minimum dose (Dmin) of the blood vessel of the PICC region, ranged from 2 to 20% in both groups, with no significant difference (conformity index: P = 0.87, Dmax: P = 0.81, Dmin: P = 0.83). There was no statistically significant difference in the D2% (P = 0.34) and D98% (P = 0.30) of the target, V20% (P = 0.34) and V30% (P = 0.34) of the heart, Dmax (P > 0.05) and Dmin (P > 0.05) of the esophagus, V5% (P = 0.34), V20% (P = 0.33), V30% (P = 0.17), and Dmean (P = 0.33) of the lungs, and Dmax (P = 0.34) of the spinal cord between the two groups of plans. Conclusion Despite the lack of significance in the dose distribution of the target and organs at risk, the effect of dosimetry in the blood vessel region of the PICC is obvious. As a result, the PICC will affect the dose distribution of the blood vessel region of the PICC and the target close to the PICC region. It is inadvisable to implant a PICC during radiation therapy.

Keywords

• dosimetry of blood vessel region
• peripherally inserted central catheter
• volumetric modulated arc therapy