FDG-PET and stereotactic body radiotherapy (SBRT) for stage I non-small-cell lung cancer

Surgical salvage following stereotactic body radiotherapy for early-stage NSCLC

“…Presently, we are unable to accurately characterise the radiological changes seen following SBRT [3], particularly at the site of treatment where marked inflammatory and fibrotic changes may resemble or obscure signs of recurrent disease [7]. Although a healthy level of clinical suspicion for recurrence should be maintained, false positives are possible (as in patient D) and the potential morbidity of unnecessary major surgery should be kept in mind.…”

Salvage surgery after high-dose radiotherapy

“…The appearance of a zone of consolidation on chest computed tomography (CT) could be radiation pneumonitis, radiation fibrosis, persisting tumor growth or local recurrence (25). Tumor serum markers as carcinoembryonic antigen (CEA) and fluorodeoxyglucose positron-emission tomographic (FDG-PET) images may be helpful in the differential diagnosis although increased FDG-uptake may persist up to 2 years after SRT without evidence of recurrence (26,27).…”

Radiotherapy and Immunotherapy Combinations in Non-small Cell Lung Cancer: A Promising Future?

“…A potential challenge after either SABR or immunotherapy when given as single agent therapies is progressive disease as defined by RECIST criteria which is in fact pseudo-progression and appears indicative of immune effector cell infiltration into the tumour prior to eventual tumour response [47]. Pseudo-progression following SABR in the treatment of stage 1 lung cancer may be observed for up to 1 year after treatment, even when PET/CT is used to reassess the treated area and low grade FDG uptake may remain and increase in intensity for up to 1 year after treatment [48]. In a recent study of Pembrolizumab as monotherapy in the treatment of melanoma, RECIST 1.1 under-estimated the clinical response rates in up to 15% of patients [49][50].…”