What is the optimal number of library plans in ART for locally advanced cervical cancer?

PURPOSE: Library-of-plans ART is used to manage daily anatomy changes in locally advanced cervical cancer. In our institute, the library contains 2 VMAT plans for patients with large cervix-uterus motion. Increasing this number could be beneficial for tissue sparing, but is burdensome while the dosimetric gain is yet unclear. This study's aim is to determine the optimal number of plans at an individual patient level. MATERIAL AND METHODS: Data of 14 treated patients were analyzed. Plan libraries were created containing 1-4 VMAT plans. Pre-treatment extent of uterus motion was defined by the 99th percentile of the Hausdorff distance (HD99). For dosimetric evaluations, OARs were contoured in daily CBCT scans, plan selection was simulated, and the V45Gy and V40Gy parameters were recorded. RESULTS: Moderate to strong correlations were found between HD99 and the volume of spared OARs. All patients benefitted from adding a 2nd plan, as is the clinical practice. For patients with a HD99 between 30 and 50mm, a 3-plan library reduced the composite V40Gy with 11-21ml compared to a 2-plan library. CONCLUSION: Patients with large uterus motion (HD99>30mm) would benefit from an extension of the plan library to 3. HD99 is an easy-to-implement criteria to select those patients pre-treatment.

Dynamics of patient reported quality of life and symptoms in the acute phase of online adaptive external beam radiation therapy for locally advanced cervical cancer.

OBJECTIVE: For locally advanced cervical cancer patients, treated with External Beam Radiotherapy (EBRT), Quality of Life (QoL) questionnaires arefrequently used to evaluate treatment-related symptoms and functioning scales. Currently, it is unknown how those evolve during the radiation treatment course. In this prospective study we report on weekly-captured patient-reported QoL and symptoms during image-guided adaptive radiotherapy (IGART) of cervical cancer patients. MATERIAL AND METHODS: Between January 2012 and September 2016, all locally advanced cervical cancer patients treated with IGART and brachytherapy with or without chemotherapy or hyperthermia, were eligible. QoL was assessed at baseline; weekly during the first five weeks of treatment; 1week, 1 and 3months after treatment, using the EORTC QLQ-C30 and the QLQ-CX24 questionnaires. Comparisons were made with an age-matched norm population. RESULTS: Among the 138 (70%) responders, most symptoms showed a moderate-to-large increase, reaching a maximum at the end of treatment, or first week after treatment with return to baseline value at 3months after treatment. While most symptoms gradually increased during the first five weeks, diarrhea and bowel cramps already markedly increased within the first three weeks to reach a plateau at the 5th week of treatment. Global health and functioning were temporarily decreased and returned to a plateau at baseline level 3months after treatment, except for cognitive functioning. CONCLUSION: A profound impact on QoL was observed during the radiation treatment course, temporarily affecting functioning. The maximum impaired was reached at the end of EBRT.