The AVOCAT study: Bicalutamide monotherapy versus combined bicalutamide plus dutasteride therapy for patients with locally advanced or metastatic carcinoma of the prostate-a long-term follow-up comparison and quality of life analysis

Compare the efficacy and tolerability of dutasteride in combination with bicalutamide to bicalutamide monotherapy in the treatment of locally advanced and metastatic prostate cancer (PCa).

One-hundred-fifty PCa patients with locally advanced or metastatic disease were prospectively enrolled and randomly assigned to receive either bicalutamide monotherapy 150 mg once daily (79 patients) or bicalutamide 150 mg plus dutasteride 0. 5 mg once daily (71 patients). Treatment response was assessed by serum PSA level measurement, and standard procedures for diagnosis of clinical progression were used during follow-up. Patient-reported quality of life (QoL) was assessed using validated questionnaires (EORTC QLQ-C30 and QLQ-PR25).

At 3 years follow-up, PSA progression was found in 52 patients [65.8 %; 95 % confidence interval (CI) 55.4-76.3] in the monotherapy group compared to 38 patients (53.5 %; 95 % CI 41.9-65.1) in the combined therapy group (p = 0.134). At the time of analysis 37 men (46.8 %; 95 % CI 35.8-57.8) in the monotherapy group had died versus 30 men (42.3 %; 95 % CI 30.8-53.7) in the combined therapy group. Median survival time was 5.4 and 5.8 years, respectively (p = 0.694). There was no statistically significant difference in the presentation frequency of adverse events between groups (p = 0.683). QoL was good and comparable between the two groups.

Both therapies were well tolerated with a good QoL. However, despite a trend toward higher efficacy of the combined therapy, progression-free survival and overall survival was not significantly different between the groups. Further research on this therapy should be performed.

SpringerPlus. 2016 May 17*** epublish ***

Siebren Dijkstra, Wim P J Witjes, Erik P M Roos, Peter L M Vijverberg, Arno D H Geboers, Jos L Bruins, Geert A H J Smits, Henk Vergunst, Peter F A Mulders

Department of Urology, Radboud University Medical Center, Geert Grooteplein Zuid 10, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands., Department of Urology, Radboud University Medical Center, Geert Grooteplein Zuid 10, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands., Department of Urology, Antonius Hospital, Bolswarderbaan 1, P.O. Box 20.000, 8600 BA Sneek, The Netherlands., Department of Urology, St. Antonius Hospital, Koekoekslaan 1, P.O. Box 2500, 3435 CM Nieuwegein, The Netherlands., Department of Urology, Slingeland Hospital, Kruisbergseweg 25, P.O. Box 169, 7000 AD Doetinchem, The Netherlands., Department of Urology, Koningin Beatrix Hospital, Beatrixpark 1, P.O. Box 9005, 7100 GG Winterswijk, The Netherlands., Department of Urology, Rijnstate Hospital, Wagnerlaan 55, P.O. Box 9555, 6800 TA Arnhem, The Netherlands., Department of Urology, Canisius Wilhelmina Hospital, Weg Door Jonkerbos 100, P.O. Box 9015, 6532 SZ Nijmegen, The Netherlands., Department of Urology, Radboud University Medical Center, Geert Grooteplein Zuid 10, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.