Incidental Findings of Malignancy of the Chest by Single Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT-CT MPI): One Year Follow-up Report

Abstract

INTRODUCTION. We recently reported 6 cases of pulmonary/hilar malignancies as the result of incidental findings (IF) on CT attenuation correction (CTAC) during SPECT-CT MPI. In this study, we examined clinical features, diagnostic procedures and clinical outcome on all patients who were had malignancies or significant IF that required further follow-up. 

METHODS. Of 1098 consecutive patients who underwent cardiac SPECT-CT MPI from 9/1/2017 to 8/31/2018, their MPI and CTAC were reviewed contemporaneously.  Patients with known history of prior pulmonary or chest malignancy were excluded. 

RESULTS. A total of 79 (7.2%) patients were identified to have significant IF on CTAC; after diagnostic CT, 47 patients were found to have significant findings that warranted further follow-up and included in this study. Eight patients (0.73%) were found to have malignancy of the chest because of IF on the CTAC.   There was no statistical difference in baseline characteristics and cancer risk factors among patients who were found to have cancer vs those without.  At the time of diagnosis, 4 patients were found to have cancer at advanced stage who all died within 12 months while 3 others had lung cancer of early stage and 1 mantle cell lymphoma were alive at a mean follow-up of 17.5+/-2.1 months. Biopsy for tissue diagnosis were performed safely: with needle biopsy, major complication occurred in 1 patient (1/9 or 11.1%); none with surgical biopsy.

CONCLUSIONS. This study underscores the importance of reviewing CTAC images obtained during cardiac SPECT-CT MPI to potentially detect clinically important incidental findings.