Setting up a lung stereotactic body radiotherapy service in a tertiary center in Eastern India: The process, quality assurance, and early experience.

ABSTRACT

CONTEXT Stereotactic body radiotherapy (SBRT) is increasingly being used for early-stage lung cancer and lung oligometastases. AIMS: To report our experience of setting up lung SBRT and early clinical outcomes. SETTINGS AND DESIGN: This was a retrospective, interventional, cohort study. SUBJECTS AND METHODS: Patients were identified from multidisciplinary tumor board meetings. They underwent four-dimensional computed tomography-based planning. The ROSEL trial protocol, the Radiation Therapy Oncology Group (RTOG) 0236, and the UK-Stereotactic Ablative Body Radiotherapy Consortium guidelines were used for target volume and organs-at-risks (OARs) delineation, dosimetry, and plan quality assessment. Each SBRT plan underwent patient-specific quality assurance (QA). Daily online image guidance using KVCT or MVCT was done to ensure accurate treatment delivery. STATISTICAL ANALYSIS USED Microsoft Excel 2010 was used for data analysis. RESULTS: Fifteen patients were treated to one or more lung tumors. One patient received helical tomotherapy in view of bilateral lung oligometastases at similar axial levels. All the remaining patients received volumetric modulated arc therapy (VMAT)-based treatment. The prescription dose varied from 40 to 60 Gy in 5-8 fractions with alternate-day treatment. The mean and median lung V20 was 5.24% and 5.16%, respectively (range, 1.66%-9.10%). The mean and median conformity indexes were 1.02 and 1.06, respectively (range, 0.70-1.18). After a median follow-up of 17 months, the locoregional control rate was 93.3%. CONCLUSIONS: SBRT was implemented using careful evaluation of OAR dose constraints, dosimetric accuracy and plan quality, patient-specific QA, and online image guidance for accurate treatment delivery. It was safe and effective for early-stage nonsmall cell lung cancer and lung metastases. Prospective data were collected to audit our outcomes.