caa a22 4500 605494630 CHVBK 20210128100527.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s00261-015-0524-7 doi (NATIONALLICENCE)springer-10.1007/s00261-015-0524-7 Pancreatic neuroendocrine tumors: correlation between histogram analysis of apparent diffusion coefficient maps and tumor grade [Elektronische Daten] [Jose Pereira, Elsa Rosado, Maria Bali, Thierry Metens, Shih-Li Chao] Purpose: To explore the role of histogram analysis of apparent diffusion coefficient (ADC) MRI maps based on entire tumor volume data in determining pancreatic neuroendocrine tumor (PNT) grade. Methods and Materials: Retrospective evaluation of 22 patients with PNTs included low-grade (G1; n=15), intermediate-grade (G2; n=4), and high-grade (G3; n=3) tumors. Regions of interest containing the lesion were drawn on every section of the ADC map containing the tumor and summated to obtain histograms for entire tumor volume. Calculated histographic parameters included mean ADC (mADC), 5th percentile ADC, 10th percentile ADC, 25th percentile ADC, 50th percentile ADC, 75th percentile ADC (ADC75), 90th percentile ADC (ADC90) and 95th percentile ADC (ADC95), skewness and kurtosis. Histogram parameters were correlated with tumor grade by repeated measures analysis of variance with Tukey-Kramer post hoc comparisons. Results: The mADC, ADC75, ADC90, and ADC95 were significantly higher in G1 tumors (1283±267; 1404±300; 1495±318; 1562±347×10−6mm2/s) compared to G2 (892±390; 952±381; 1036±384; 1072±374×10−6mm2/s) and to G3 tumors (733±225; 864±284; 1008±288; 1152±192×10−6mm2/s) (p value <0.05). Skewness and kurtosis were significantly different between G1 (0.041±0.466; 2.802±0.679) and G3 (1.01±1.140; 5.963±4.008) tumors (p value <0.05). Tumor volume (mL) was significantly higher on G3 (55±15.7) compared to G1 (1.9±2.7) and G2 (4.5±3.6) tumors (p value <0.05). In this small sample size, we did not detect statistically significant parameters between G2 (n=4) and G3 (n=3) tumors. Conclusions: Histographic analysis of ADC maps on the basis of the entire tumor volume can be useful in differentiating histologic grades of PNTs. Springer Science+Business Media New York, 2015 Pancreatic nationallicence Neuroendocrine nationallicence Histogram nationallicence ADC nationallicence Pereira Jose Department of Radiology, Centro Hospitalar de Lisboa Central, Lisbon, Portugal aut Rosado Elsa Department of Radiology, Hospital Fernando Fonseca, Amadora, Portugal aut Bali Maria Department of Radiology, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium aut Metens Thierry Department of Radiology, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium aut Chao Shih-Li Department of Radiology, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium aut Abdominal Imaging Springer US; http://www.springer-ny.com 40/8(2015-10-01), 3122-3128 0942-8925 40:8<3122 2015 40 261 https://doi.org/10.1007/s00261-015-0524-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00261-015-0524-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Pereira Jose Department of Radiology, Centro Hospitalar de Lisboa Central, Lisbon, Portugal aut NATIONALLICENCE 700 1- Rosado Elsa Department of Radiology, Hospital Fernando Fonseca, Amadora, Portugal aut NATIONALLICENCE 700 1- Bali Maria Department of Radiology, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium aut NATIONALLICENCE 700 1- Metens Thierry Department of Radiology, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium aut NATIONALLICENCE 700 1- Chao Shih-Li Department of Radiology, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium aut NATIONALLICENCE 773 0- Abdominal Imaging Springer US; http://www.springer-ny.com 40/8(2015-10-01), 3122-3128 0942-8925 40:8<3122 2015 40 261