title: PSA bounce after ¹²⁵I-brachytherapy for prostate cancer as a favorable prognosticator.
abstract: BACKGROUND
  Permanent low-dose-rate brachytherapy (BT) with iodine 125 is an established curative treatment for localized prostate cancer. After treatment, prostate-specific antigen (PSA) kinetics may show a transient rise (PSA bounce). Our aim was to investigate the association of PSA bounce with biochemical control.
  
  
  METHODS
  Patients treated with BT in Switzerland were registered in a prospective database. Only patients with a follow-up of at least 2 years were included in our analysis. Clinical follow-up and PSA measurements were assessed after 1.5, 3, 6, and 12 months, and annually thereafter. If PSA increased, additional follow-up visits were scheduled. Cases of PSA bounce were defined as a rise of at least 0.2 ng/ml above the initial PSA nadir with a subsequent decline to or below the initial nadir without treatment. Biochemical failure was defined as a rise to nadir + 2 ng/ml.
  
  
  RESULTS
  Between March 2001 and November 2010, 713 patients with prostate cancer undergoing BT with at least 2 years of follow-up were registered. Median follow-up time was 41 months. Biochemical failure occurred in 28 patients (3.9 %). PSA bounce occurred in 173 (24.3 %) patients; only three (1.7 %) patients with PSA bounce developed biochemical failure, in contrast to 25 (4.6 %) patients without previous bounce (p < 0.05). The median time to bounce was 12 months, the median time to biochemical failure was 30 months. The median bounce increase was 0.78 ng/ml. Twenty-eight patients with bounce (16.5 %) had a transient PSA rise of + 2 ng/ml above the nadir.
  
  
  CONCLUSIONS
  In most cases, an early increase in PSA after BT indicates PSA bounce and is associated with a lower risk of biochemical failure.
authors.affiliation: Department of Urology, Cantonal Hospital St. Gallen, Rorschacher Strasse 95, 9007, St. Gallen, Switzerland. daniel.engeler@kssg.ch.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Engeler
authors.affiliation: Department of Urology, Cantonal Hospital St. Gallen, Rorschacher Strasse 95, 9007, St. Gallen, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schwab
authors.affiliation: Department of Radiation Oncology, Lindenhofspital Berne, Berne, Switzerland.
authors.forename: Armin F
authors.initials: AF
authors.lastname: Thöni
authors.affiliation: Department of Urology, Hirslanden Klinik Aarau, Aarau, Switzerland.
authors.forename: Werner
authors.initials: W
authors.lastname: Hochreiter
authors.affiliation: Department of Urology, Klinik Uroviva Bülach, Bülach, Switzerland.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Prikler
authors.affiliation: Department of Urology, Cantonal Hospital Zug, Zug, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Suter
authors.affiliation: Department of Urology, Cantonal Hospital Lucerne, Lucerne, Switzerland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Stucki
authors.affiliation: Department of Radiation Oncology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Johann
authors.initials: J
authors.lastname: Schiefer
authors.affiliation: Department of Radiation Oncology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Ludwig
authors.initials: L
authors.lastname: Plasswilm
authors.affiliation: Department of Urology, Cantonal Hospital St. Gallen, Rorschacher Strasse 95, 9007, St. Gallen, Switzerland.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Schmid
authors.affiliation: Department of Radiation Oncology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Paul Martin
authors.initials: PM
authors.lastname: Putora
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D001918:Brachytherapy; D003131:Combined Modality Therapy; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000175:diagnosis; D011379:Prognosis; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy / Q000532:radiotherapy*; D013557:Switzerland
chemical_list: D014408:Biomarkers, Tumor; D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen
keywords: Biochemical relapse; Brachytherapy; PSA bounce; Prognosis; Prostate cancer