Quality and Value of Subspecialty Reinterpretation of Thoracic CT Scans of Patients Referred to a Tertiary Cancer Center.

INTRODUCTION: Patients referred to tertiary cancer centers often present with imaging studies performed and interpreted at other health care institutions. Although reinterpretation of imaging performed at another health care institution can reduce repeat imaging, unnecessary radiation dose, and cost, the benefit is uncertain. The purpose of this study is to evaluate the quality of initial imaging studies of patients seeking a second opinion at a tertiary cancer center, to compare the accuracy of initial interpretations to reinterpretations performed by subspecialty trained radiologists at a tertiary oncologic center, and to determine the potential impact on patient management.
METHODS: An institutional review board-approved retrospective, single-institution database review was performed in 120 new patients presenting to the thoracic surgery clinics at our institution from 2010 through 2013, with initial chest CTs performed at another institution. Two thoracic radiologists blinded to the interpretation independently assessed the quality and performed a reinterpretation of 52 CTs. Fisher's exact tests were used to compare the frequency with which clinically important staging parameters appeared in the reinterpretations and initial reports. Discrepancies between the reinterpretations and initial interpretations were adjudicated independently by two thoracic radiologists at different tertiary cancer institutions to determine which interpretations were more accurate. The impact of discrepancies on clinical management was evaluated based on National Comprehensive Cancer Network guidelines.
RESULTS: Of the 52 CTs, 32 (62%) were of inadequate image quality for staging. In 17 of 52 (33%), discrepancies were identified between reinterpretations and initial interpretations. For discrepancies, the reinterpretation was judged to be more accurate for staging than the initial interpretation. In nine of these patients, staging parameters were omitted in the initial interpretations that precluded adequate staging. In the remaining eight patients, six were upstaged, one was downstaged, and one was unchanged by the reinterpretation.
CONCLUSIONS: Imaging studies from outside institutions are of variable image quality and often not adequate for appropriate staging of thoracic malignancies. Reinterpretation can decrease repeat imaging and associated technical costs. Additionally, the accuracy of staging is improved by reinterpretation of CTs by subspecialty trained radiologists and can significantly impact clinical management.