(ChemotherapyAdvisor) – CT-guided percutaneous biopsies are warranted in patients with a new lung lesion and a known primary malignancy to detect second malignancies or benign etiologies such as infection and inflammation, investigators reported during the Society of Interventional Radiology’s 37th Annual Scientific Meeting in San Francisco, CA, USA, on March 25.
Amin et al. conducted a retrospective review of CT-guided biopsies performed between October 2010 and October 2011 at the University of Chicago Medical Center. The goal of the study was to determine incidence of alternative etiology among patients with a known primary malignancy — intrathoracic or extrathoracic— presenting with newly imaged lung lesions referred to the radiology department for image-guided biopsy to confirm metastasis.
Of 104 patients identified, pathology data were subsequently collected from 55 patients with a history of a known primary cancer in whom metastatic disease to the lung was suspected or questioned.
Twenty (36%) of the 55 patients biopsied yielded results discordant with the initial prebiopsy suspicion for metastatic disease, they reported. After eliminating seven nondiagnostic biopsies and three biopsies performed to obtain more tissue for an assay of diagnostic markers, the rate of discordant results was 44%.
Among the discordances, 50% were interpreted as a second primary malignancy, 30% as inflammatory/abscess, and 15% as other lesions compatible with benign processes, such as organizing pneumonia, or fibrosis/scarring.