Fernanda Dias Gonzalez Guindalini MD, Abstract Co-Author: Grant, Siemens AG

Marcos Paulo Ferreira Botelho MD, Abstract Co-Author: Grant, Siemens AG

Keyur Parekh MD, Presenter: Grant, Siemens AG

Adeel Rahim Seyal MD, Abstract Co-Author: Grant, Siemens AG

Hamid Chalian MD, Abstract Co-Author: Nothing to Disclose

Vahid Yaghmai MD, Abstract Co-Author: Nothing to Disclose

To compare the reproducibility of mRECIST and volumetric quantification of viable tissue within HCC lesions after locoregional therapy.

This HIPAA compliant retrospective study was IRB approved. Fifty-eight patients with known diagnosis of HCC treated with 90Y radioembolization and follow-up MDCT study after the treatment were included. Two independent radiologists measured the viable tissue within the lesion, defined as arterially enhancing component, using both mRECIST and volumetric quantification, assessed manually and with semi-automated segmentation software, respectively. Paired t-test, Lin’s concordance correlation coefficient (rc), and precision were used to assess intra- and interobserver reproducibility.

Fifty-eight HCC lesions in 58 patients, 43 males (74.1%) and 15 females (25.9%), were evaluated. The mean age was 67.1+11.8 years. Intraobserver comparison showed comparable volumetric measurements of the viable tissue (P=0.744) while mRECIST measurements were significantly different (P=0.025). Concordance correlation coefficient was excellent for volumetry (rc=0.999) and moderate for mRECIST (rc=0.953) with higher precision of 22.8% for volumetry in comparison with 32.0% for mRECIST. Interobserver comparison showed comparable measurements for mRECIST (P=0.306) and volumetry (P=0.463) but concordance correlation coefficient for volumetric measurement of the viable tissue was excellent (rc=0.999) while it was moderate for mRECIST (rc=0.918). Volumetric measurement also had better precision (12.0%) compared to mRECIST (35.5%).

Volumetric quantification of the viable tissue in HCC lesions demonstrated better inter- and intraobserver correlation as well as precision in comparison with mRECIST.

Necrosis in treated HCC can have heterogeneous distribution. Volumetric quantification of viable tissue demonstrated better agreement between readers than mRECIST.

Gonzalez Guindalini, F, Botelho, M, Parekh, K, Seyal, A, Chalian, H, Yaghmai, V, Reproducibility of mRECIST and Volumetric Quantification of Viable Tissue in HCC Lesions.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13044407.html