3341. Role of Contrast-Enhanced Susceptibility-Weighted Imaging (CE-SWI) for the Assessment of Response and Progression in Desmoid Fibromatosis
Authors* Denotes Presenting Author
Raul Valenzuela *;
The University of Texas MD Anderson Cancer Center
Elvis Duran Sierra;
The University of Texas MD Anderson Cancer Center
Mathew A. Canjirathinkal;
The University of Texas MD Anderson Cancer Center
Colleen M. Costelloe;
The University of Texas MD Anderson Cancer Center
John E. Madewell;
The University of Texas MD Anderson Cancer Center
William A. Murphy Jr.;
The University of Texas MD Anderson Cancer Center
Behrang Amini;
The University of Texas MD Anderson Cancer Center
Objective:
Subjective clinical imaging evaluations often consider progressive desmoid tumors to have a higher proportion of T2 hyperintense and T1 shortened enhancing components, whereas responding or mature more collagenized tumors demonstrate a higher proportion of T2 hypointense nonenhancing parts. This study aimed to determine the utility of the novel use of contrast-enhanced susceptibility-weighted imaging (CE-SWI) as a single sequence capable of simultaneously separating the T1 shortening enhancing, T2 hyperintense immature, and the T2 hypointense collagenized mature components, using volumetric measurements and first-order radiomic features.
Materials and Methods:
This pilot study included 10 single-lesion extremity desmoid fibromatosis patients undergoing standard-of-care MRI examinations, including CE-SWI, performed between March 2021 and May 2023. Three-dimensional manual tumor segmentation was performed using the MIM commercial software in 48 volumes of interest. Maximum diameter, volume, and modified Choi (mChoi) measurements were computed from CE-SWI and T2-STIR sequences. In addition, five first-order radiomic features, including mean, skewness, kurtosis, and 10th and 90th percentiles, were computed using in-house developed software CARPI-AF (Cancer Radiomic and Perfusion Imaging Automated Framework).
Results:
Two patients displayed progression by the T2-based RECIST reference standard. In the same group, concordant progression was detected by CE-SWI volume and mChoi at an average of 4.5 months earlier than T2-based RECIST. Eight patients were classified as stable disease by T2-based RECIST. No cases of concordant stability were observed by T2 or CE-SWI-based volume or Choi. From the T2-based stable RECIST group, discrepant progression was determined in four patients by an increase of greater than 25% of T2-based volume (in three patients) and CE-SWI-based volume (in two patients). From the T2-based stable RECIST group, a discrepant positive response was determined in four patients predicted by CE-SWI mChoi (in three patients) and T2 mChoi (in four patients).
Conclusion:
This study suggests that trained cancer radiologists tend to be relatively insensitive to early volumetric progression and sensitive to signal-based (mChoi) response assessment. The novel use of CE-SWI-based volumetric and mChoi measurements could improve the prediction of response/progression in desmoid tumors by providing a better evaluation using tri-dimensional tumor size assessment and increased discrimination between the collagenized mature component and the enhancing immature components, respectively, with predominant T2 hypointense collagenized mature-responding and T2 hyperintense immature-progressive disease. CE-SWI tends to outperform T2, demonstrating a higher proportion of 90th-percentile voxels, which are typically dominant in immature tumor components.
