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Active surveillance before radiotherapy: Outcome and predictive factors for multiple biopsies before treatment
Alexandre Alcaidinho1, Guila Delouya1, Jean-Paul Bahary1
1Department of Radiation Oncology, Centre hospitalier de l'Université de Montréal, Montreal, QC, Canada.
Introduction:
We aimed to investigate whether patients on active surveillance (AS) had worse outcomes than patients who received immediate treatment with radiotherapy and whether a Gleason grade progression on repeat biopsy influenced outcome.
Methods:
From our institutional database, we identified 2001 patients treated between 2005 and 2019 with primary external beam radiation therapy or brachytherapy. Biochemical recurrence (BCR) was analyzed in relation to clinical factors such as a Gleason grade progression or having multiple biopsies vs. only one biopsy. Patients on AS were identified as those who had undergone ≥2 biopsies. We used log-rank tests for univariate analysis (UVA) and Cox regression analysis for multivariable analysis (MVA).
Results:
Of 2001 patients, 374 (19%) patients had ≥2 biopsies before treatment, of which 48% presented with a Gleason grade progression of mostly to Gleason 3+4 (36%); 32% had a cancer volume increase on biopsy and 16% had no significant change on biopsy. For patients with ≥2 biopsies, median time from first biopsy to treatment was 22.0 months (interquartile range [IQR] 14.7-36.1). By UVA, patients with Gleason grade progression (n=105) had a worse BCR-free rate (p=0.02) than patients who had no grade progression on repeat biopsy or only one biopsy. On MVA, this effect was lost. Having ≥2 biopsies was not a significant negative prognostic factor on UVA (p=0.2) or MVA.
Conclusions:
In our experience, radiotherapy after a period of AS, even with Gleason grade progression, did not lead to worse outcomes compared to patients who had radiotherapy after only one biopsy.

