Five-year effectiveness of low-dose-rate brachytherapy: comparisons with nomogram predictions in patients with non-metastatic prostate cancer presenting significant control of intra-and periprostatic disease
Jörg S. Zimmermann, MD1,2,, Rudolf Osieka, MD3, Thorsten Bruns, MD4, Helge Hollberg, MD5, Bastian Wiechmann, MD3, Olaf Netzbandt, MD4, Jörg Sablotny, MD4, Michael Malade, MD4, Matthias Heitz, MD4, Fritz Bernhardt, MD4, Jörg Tiemann, MD4, Marc Wilkens, MD4, Tom Brüske, MD6, Utz Welker, MD7, Volker Heinemann, MD3, Petra Zimmermann, MD1, Salvador Fernandez de la Maza, MD2, Dietrich Pfeiffer, MD8, Prof. Roland Tauber, MD9, Dorothea Thomas, PhD1,2,, Christos Moustakis, PhD1,2,10
1Praxis für Brachytherapie, Praxiszentrum Alstertal, Hamburg, 2 Katholisches Marienkrankenhaus, Hamburg, 3Urologikum Hamburg, 4Urology practice, Hamburg, 5Urology practice, Buxtehude, 6Urology practice, Ahrensburg, 7Urology practice, Itzehoe, 8Department of Urology, Asklepios-Klinik Barmbek, Hamburg, 9Department of Urology, Asklepios-Klinik St. Georg, Hamburg, 10Klinik für Strahlentherapie, Abteilung Medizinische Physik, Universitätsklinik Münster, Germany
Purpose: To assess the effectiveness of low-dose-rate (LDR) brachytherapy in patients with localized prostate cancer and to compare the outcome with predictions from Kattan and Partin nomograms at 60 months after seed im- plantation.
Material and methods: One thousand, one hundred and eighty-seven patients with localized prostate cancer at low-, intermediate-, or high-risk of progression received LDR brachytherapy using iodine-125 seeds with curative intent, applied as monotherapy or in combination with external beam radiation therapy (EBRT), and/or androgen deprivation therapy (ADT). At 60 months after seed implantation, data of 1,064 patients (1,058 alive + 6 who died of prostate cancer) were analyzed for biochemical progression-free survival (bPFS) based on prostate-specific anti- gen (PSA) levels using the Phoenix definition. Five-year bPFS probabilities were determined for various risk group classifications (d’Amico, Mt. Sinai, MSKCC/Seattle, NCCN). Outcomes were also compared to patient-individual- ized nomogram predictions of 5-year bPFS (Kattan 2002) and probability of organ-confined disease (Kattan 2002, Partin 2007).
Results: Overall, 93.3% (993/1,064) of the patients were free of biochemical progression within 5 years, while the average 5-year bPFS probability according to the Kattan nomogram was significantly lower (85%, p < 0.001). Outcomes were significantly better than Kattan nomogram predictions in the subgroup of patients with monotherapy as well as in patients additionally treated with EBRT. Comparison of the overall outcome with nomogram predictions for organ-con- fined disease (Kattan nomogram: 50%; Partin nomogram: 65%) revealed a significant probability of LDR brachytherapy to destroy periprostatic tumor spread (p < 0.001) in all risk group constellations, even in high-risk patients.
Conclusions: The results indicate high effectiveness of LDR brachytherapy in all risk groups, significantly better than predicted with the Kattan nomogram in most subgroups. The significant superiority of LDR brachytherapy com- pared to nomogram predictions of organ-confined disease suggests that LDR brachytherapy effectively controls both intra- and periprostatic disease.