title: ADC histogram analysis for adrenal tumor histogram analysis of apparent diffusion coefficient in differentiating adrenal adenoma from pheochromocytoma.
abstract: To determine the diagnostic performance of apparent diffusion coefficient (ADC) histogram analysis in diffusion-weighted (DW) magnetic resonance imaging (MRI) for differentiating adrenal adenoma from pheochromocytoma.
  
  
  
  We retrospectively evaluated 52 adrenal tumors (39 adenomas and 13 pheochromocytomas) in 47 patients (21 men, 26 women; mean age, 59.3 years; range, 16-86 years) who underwent DW 3.0T MRI. Histogram parameters of ADC (b-values of 0 and 200 [ADC200], 0 and 400 [ADC400], and 0 and 800 s/mm2[ADC800])-mean, variance, coefficient of variation (CV), kurtosis, skewness, and entropy-were compared between adrenal adenomas and pheochromocytomas, using the Mann-Whitney U-test. Receiver operating characteristic (ROC) curves for the histogram parameters were generated to differentiate adrenal adenomas from pheochromocytomas. Sensitivity and specificity were calculated by using a threshold criterion that would maximize the average of sensitivity and specificity.
  
  
  
  Variance and CV of ADC800were significantly higher in pheochromocytomas than in adrenal adenomas (P < 0.001 and P = 0.001, respectively). With all b-value combinations, the entropy of ADC was significantly higher in pheochromocytomas than in adrenal adenomas (all P ≤ 0.001), and showed the highest area under the ROC curve among the ADC histogram parameters for diagnosing adrenal adenomas (ADC200, 0.82; ADC400, 0.87; and ADC800, 0.92), with sensitivity of 84.6% and specificity of 84.6% (cutoff, ≤2.82) with ADC200; sensitivity of 89.7% and specificity of 84.6% (cutoff, ≤2.77) with ADC400; and sensitivity of 94.9% and specificity of 92.3% (cutoff, ≤2.67) with ADC800.
  
  
  
  ADC histogram analysis of DW MRI can help differentiate adrenal adenoma from pheochromocytoma.
  
  
  
  3 J. Magn. Reson. Imaging 2017;45:1195-1203.
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Tomokazu
authors: T
authors: Umanodan
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Yoshihiko
authors: Y
authors: Fukukura
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Yuichi
authors: Y
authors: Kumagae
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Toshikazu
authors: T
authors: Shindo
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Masatoyo
authors: M
authors: Nakajo
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Koji
authors: K
authors: Takumi
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Masanori
authors: M
authors: Nakajo
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Hiroto
authors: H
authors: Hakamada
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Aya
authors: A
authors: Umanodan
authors: Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.
authors: Takashi
authors: T
authors: Yoshiura
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging* / Q000473:pathology; D000293:Adolescent; D000310:Adrenal Gland Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D000311:Adrenal Glands / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010673:Pheochromocytoma / Q000000981:diagnostic imaging* / Q000473:pathology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
keywords: adenoma; adrenal gland neoplasms; apparent diffusion coefficient; diffusion-weighted MRI; histogram analysis; pheochromocytoma