title: Focus on the tumour periphery in MRI evaluation of soft tissue sarcoma: infiltrative growth signifies poor prognosis.
abstract: Purpose. Infiltrative microscopical peripheral growth of soft tissue sarcomas (STS) has been shown to be of prognostic importance and preoperative risk stratification could individualize neoadjuvant treatment. Patients and methods. We assessed peripheral tumour growth pattern on preoperative MRI from 78 STS. The findings were correlated to histopathology and to outcome. Results. The MRI-based peripheral tumour growth pattern was classified as pushing in 34 tumours, focally infiltrative in 25, and diffusely infiltrative in 19. All tumours with diffuse infiltration on MRI also showed microscopical infiltration, whereas MRI failed to identify infiltration in two-thirds of the microscopically infiltrative tumours. Diffusely infiltrative growth on MRI gave a 2.5 times increased risk of metastases (P = .01) and a 3.7 times higher risk of local recurrence (P = .02). Discussion. Based on this observation we suggest that MRI evaluation of STS should focus on the peripheral tumour growth pattern since it adds prognostic information of value for decisions on neoadjuvant therapies.
authors.affiliation: Department of Oncology, Institute of Clinical Sciences, Lund University Hospital, 221 85 Lund, Sweden.
authors.forename: Josefin
authors.initials: J
authors.lastname: Fernebro
authors.forename: Marie
authors.initials: M
authors.lastname: Wiklund
authors.forename: Kjell
authors.initials: K
authors.lastname: Jonsson
authors.forename: Pär-Ola
authors.initials: PO
authors.lastname: Bendahl
authors.forename: Anders
authors.initials: A
authors.lastname: Rydholm
authors.forename: Mef
authors.initials: M
authors.lastname: Nilbert
authors.forename: Jacob
authors.initials: J
authors.lastname: Engellau