MRI surveillance for musculoskeletal sarcoma recurrence: is axial-only imaging good enough?

Abstract

The goal of this study is to compare the sensitivity, accuracy, and specificity of detection of musculoskeletal sarcoma local recurrence (LR) using axial-only MRI compared with multiplanar MRI. This retrospective study included 101 patients (47 with pathology-proven LR, 54 without recurrence) who underwent pre- and post-operative MRIs between 2013 and 2023 at a single academic center. Three fellowship-trained musculoskeletal radiologists independently reviewed anonymized MRIs. Initial review included only the axial sequences from the surveillance MRIs. Secondary review following a 6-month washout included all sequences from the multiplanar surveillance MRIs. No statistically significant differences in accuracy, sensitivity, and specificity were observed between axial-only and complete (multiplanar) MRI analyses (p > 0.05). Accuracy of LR detection with axial-only vs. complete (multiplanar) MRI was 94.5% vs. 93.1% (Reader 1), 87.1% vs. 91.1% (Reader 2), and 82.7% vs. 86.1% (Reader 3). LR size ranged from 0.7 to 8.9 cm (mean 3.2 cm, median 2.6 cm). All missed recurrences when using axial-only surveillance MRI measured < 2 cm. Inter-reader agreement improved from 0.768 (axial-only) to 0.834 (complete MRI). Surveillance MRI using axial sequences alone demonstrated comparable accuracy, sensitivity, and specificity to multiplanar MRI for detecting musculoskeletal sarcoma LR.