title: Evaluation of the larynx for tumour recurrence by diffusion-weighted MRI after radiotherapy: initial experience in four cases.
abstract: Radiotherapy-induced changes in the soft tissues of the neck hamper the early detection of persistent or recurrent tumour by clinical examination and imaging procedures. Diffusion-weighted (DW) MRI is a non-invasive technique capable of probing tissue properties by measuring the movement of water. The purpose of the ongoing study is to examine the usefulness of DW-MRI for differentiation of persistent or recurrent tumour from post-radiotherapeutic sequelae or complications. Four patients, suspected of tumour recurrence after radiotherapy for laryngeal squamous cell carcinoma, were examined using a DW-MRI sequence on a clinical 1.5 T MR system prior to surgery. In two patients, the DW-MRI images showed an asymmetric hyperintense lesion on b1000 images with low apparent diffusion coefficient (ADC)-value, compatible with tumour on histopathology. All surrounding tissue presented high ADC values and absent signal on the b1000 images, histopathologically correlating to post-radiotherapeutic changes. The images of the third and fourth patient showed absent or minimal symmetric hyperintensity of the laryngeal soft tissues on the b1000 images and high ADC-values. In these cases, the histopathological diagnosis of radionecrosis was made and no tumour was found. In all four cases, differentiation of tumoral tissue from radiotherapy-induced tissue alterations was possible with DW-MRI.
authors.affiliation: Department of Radiology, University Hospitals Leuven, Leuven, Belgium.
authors.forename: V
authors.initials: V
authors.lastname: Vandecaveye
authors.forename: F
authors.initials: F
authors.lastname: de Keyzer
authors.forename: V
authors.initials: V
authors.lastname: Vander Poorten
authors.forename: K
authors.initials: K
authors.lastname: Deraedt
authors.forename: H
authors.initials: H
authors.lastname: Alaerts
authors.forename: W
authors.initials: W
authors.lastname: Landuyt
authors.forename: S
authors.initials: S
authors.lastname: Nuyts
authors.forename: R
authors.initials: R
authors.lastname: Hermans
mesh_terms: D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D007822:Laryngeal Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*