Presentation on theme: "What is the appropriate margin for focal therapy of prostate cancer when using MRI/MRSI for treatment planning? Proposed secondary study for ACRIN 6659."— Presentation transcript:
1 What is the appropriate margin for focal therapy of prostate cancer when using MRI/MRSI for treatment planning?Proposed secondary study for ACRIN 6659 dataFergus Coakley MD, Professor of Radiology and Urology,Chief, Abdominal Imaging, University of California San Francisco
2 ObjectiveDetermine the appropriate margin for focal therapy of prostate cancer when planned from MRI/MRSI
3 BackgroundIncreasing interest in focal therapy as “middle way” for prostate cancer treatmentActive surveillance – minimalistDefinitive treatment (RRP or RT) – high morbidityThree requirements for focal therapy:Clinical selection – no consensusRadiological selection – MRI criteria on next slideAdequate margin – purpose of this proposal
4 UCSF selection study88 patients with MRI/MRSI before RRP and with detailed tumor mapsMRI/MRSI reviewed by two independent readersDominant treatable foci = largest lesion & > 0.5ccResults:ALL visible lesions on T2 with ≥0.54 cm3 of concordant MRSI abnormality (n = 27 and 25 for reader 1 and 2, respectively) were correctly identified dominant treatable tumor foci
5 Proposal (two steps) Apply UCSF criteria to ACRIN database T2 visible & ≥0.54 cm3 concordant MRSITwo readers (remote or travel to ACRIN HQ?)Anticipate small number will meet criteria (<10?)Co-register digital pathology with T2Pick largest/best T2 image and “best match” pathology slideMorph gland outline on pathology to T2 (allows margin measurement using MRI calipers)Measure maximum margin (per quadrant and separate capsular from non-capsular?)
6 “Best match” T2 MRI and pathology slice Example“Best match” T2 MRI and pathology slice
9 Measure margins – maximum capsular and non-capsular plus by quadrant? ExampleMeasure margins – maximum capsular and non-capsular plus by quadrant?
10 AnalysisPresumably will be essentially descriptive – what margin would have encompassed all the tumors?Issues for discussion:Explore additional selection criteria?More than two reads?Can readings be done remotely?Who will fuse images and measure margins?Funding level? Travel and/or time?