1. Dosimetry doesn't seem to predict the control of organ-confined prostate cancer after I-125 brachytherapy. Evaluation in 150 patients.
- Author
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Gastaldi E, Chiono L, Gallo F, Schenone M, Ninotta G, Chiarlone R, Ghiso G, and Giberti C
- Subjects
- Aged, Biomarkers, Tumor blood, Biopsy, Dose-Response Relationship, Radiation, Follow-Up Studies, Humans, Male, Middle Aged, Neoplasm Staging, Patient Selection, Prostate-Specific Antigen blood, Prostatic Neoplasms blood, Prostatic Neoplasms diagnostic imaging, Prostatic Neoplasms pathology, Radiography, Radiometry, Retrospective Studies, Risk Assessment, Surveys and Questionnaires, Treatment Failure, Treatment Outcome, Brachytherapy adverse effects, Iodine Radioisotopes therapeutic use, Prostatic Neoplasms radiotherapy
- Abstract
Objective: To evaluate the dose-response relationship (D90 >144 Gy: probable absence of biochemical failure) in patients with prostate cancer treated by iodine-125 (I-125) brachytherapy., Material and Methods: From May 1999 to December 2006, 150 patients were treated by I-125 brachytherapy. The median follow-up was 60 months. All patients had clinical stage T1-T2, PSA < or =10 ng/ml, Gleason Scores < or = 3+3=6, IPSS >14 ml/sec. and prostate weight <50 gr. Implantation was ultrasound-guided, using a real-time technique and loose seeds of I-125 (dose 160 Gy). After 30 days, a post-implantation assessment was performed by pelvic CT scan for a definitive evaluation of the D90. All patients were subjected to clinical evaluation, PSA dosage and compilation of IPSS and IEFF questionnaires. In the event of biochemical failure (ASTRO), a prostate biopsy was performed. A D90 >144 Gy was considered the cut-off in order to predict the absence of biochemical failure., Results: Biochemical failure was observed in 9 patients: 5 with positive and 4 with negative prostate biopsies. The D90 >144 Gy cut-off was not achieved in 18 patients at the post-implantation assessment, however only 2 of them (one of whom had a positive biopsy) had biochemical failure (11.1%). On the other hand, only 2 of the 9 patients with biochemical failure had a D90 < 144 Gy while 6 patients had D90 >150 Gy, 5 with positive prostate biopsies., Conclusions: In our experience, the D90 >144 Gy cut-off does not seem to predict, in a reliable way, the control of prostate cancer following brachytherapy. Limitations of the analysis were the number of the patients, the learning curve, dosimetry processing and the relatively short follow-up.
- Published
- 2009