title: Extracranial Soft-Tissue Tumors: Repeatability of Apparent Diffusion Coefficient Estimates from Diffusion-weighted MR Imaging.
abstract: Purpose To assess the repeatability of apparent diffusion coefficient (ADC) estimates in extracranial soft-tissue diffusion-weighted magnetic resonance imaging across a wide range of imaging protocols and patient populations. Materials and Methods Nine prospective patient studies and one prospective volunteer study, performed between 2006 and 2016 with research ethics committee approval and written informed consent from each subject, were included in this single-institution study. A total of 141 tumors and healthy organs were imaged twice (interval between repeated examinations, 45 minutes to 10 days, depending the on study) to assess the repeatability of median and mean ADC estimates. The Levene test was used to determine whether ADC repeatability differed between studies. The Pearson linear correlation coefficient was used to assess correlation between coefficient of variation (CoV) and the year the study started, study size, and volumes of tumors and healthy organs. The repeatability of ADC estimates from small, medium, and large tumors and healthy organs was assessed irrespective of study, and the Levene test was used to determine whether ADC repeatability differed between these groups. Results CoV aggregated across all studies was 4.1% (range for each study, 1.7%-6.5%). No correlation was observed between CoV and the year the study started or study size. CoV was weakly correlated with volume (r = -0.5, P = .1). Repeatability was significantly different between small, medium, and large tumors (P < .05), with the lowest CoV (2.6%) for large tumors. There was a significant difference in repeatability between studies-a difference that did not persist after the study with the largest tumors was excluded. Conclusion ADC is a robust imaging metric with excellent repeatability in extracranial soft tissues across a wide range of tumor sites, sizes, patient populations, and imaging protocol variations. Online supplemental material is available for this article.
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Winfield
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Nina
authors.initials: N
authors.lastname: Tunariu
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Mihaela
authors.initials: M
authors.lastname: Rata
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Keiko
authors.initials: K
authors.lastname: Miyazaki
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Neil P
authors.initials: NP
authors.lastname: Jerome
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Michael
authors.initials: M
authors.lastname: Germuska
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Blackledge
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: David J
authors.initials: DJ
authors.lastname: Collins
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Johann S
authors.initials: JS
authors.lastname: de Bono
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Yap
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Nandita M
authors.initials: NM
authors.lastname: deSouza
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Doran
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Dow-Mu
authors.initials: DM
authors.lastname: Koh
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Martin O
authors.identifier: 0000-0002-0756-5368
authors.initials: MO
authors.lastname: Leach
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Christina
authors.initials: C
authors.lastname: Messiou
authors.affiliation: From the Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Division of Clinical Studies (J.S.d.B., T.A.Y.), the Institute of Cancer Research and Royal Marsden Hospital, London, England; MRI Unit (J.M.W., N.T., M.R., K.M., N.P.J., M.G., M.D.B., D.J.C., N.M.d.S., S.J.D., D.M.K., M.O.L., C.M., M.R.O.) and Drug Development Unit (J.S.d.B., T.A.Y.), the Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, England.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Orton
mesh_terms: D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging*