Video-based postural alignment improves accuracy of breath hold treatment delivery in breast cancer patients

Adjuvant radiotherapy can be considered the standard of care for patients diagnosed with primary breast cancer who have undergone breast-conserving surgery. Left breast cancer receiving adjuvant deep inspiration breath hold (DIBH) were evaluated. A technique for monitoring patient position during DIBH is the surface guided radiation therapy (SGRT) as Vision AlignRT. The aim of this study was to estimate setup accuracy with AlignRT compared to AlignRT Advance in a cohort of patients undergoing DIBH treatment of breast cancer.

One hundred and fifty-four patients were studied. Patient positioning was informed using SGRT and verified by cone beam computed tomography (CBCT). Patients were divided into groups (G) based on treatment volume and version of Vision AlignRT. Comparison was performed by two tailed t-test. Data were deemed as statistically significant if p < 0.001.

The setup error for all patients treated with DIBH radiotherapy (RT) was calculated by CBCT. For left breast treatments, the interfractional displacement in the longitudinal and vertical directions was significantly (p < 0.001) reduced in patients positioned with the advanced version. For breast and supraclavicular lymph node chain and/or internal mammary chain treatments, interfractional displacement in the lateral and vertical directions was significantly (p < 0.001) reduced when the advanced version was used, while for longitudinal displacement the reduction was not significant.

Positioning with AlignRT Advance is more accurate for either left breast only or left breast and supraclavicular lymph node chain and/or internal mammary chain treatments.