[Follow-up after lung stereotactic radiotherapy]

Nowadays, bronchopulmonary stereotactic body radiotherapy is recommended as the standard of care in treating medically inoperable patients with curative intent according to guidelines of multiple organizations. Changes in lung density on computed tomography are common after stereotactic body radiotherapy and can confound the early detection of recurrence. Radiation-induced computed tomography lung changes after bronchopulmonary stereotactic body radiotherapy differ from those observed after conventionally fractionated radiotherapy. It is mandatory to standardize and simplify our clinical, radiological and functional evaluation criteria to better distinguish tumor progression and radiation-induced pneumonitis. We performed a literature review to describe post-stereotactic body radiotherapy findings on computed tomography and positron emission tomography, identify imaging characteristics that predict recurrence and propose a follow-up algorithm.