Transcript Intermittent Androgen Deprivation Therapy (IADT) in the Treatment

Intermittent Androgen Deprivation Therapy (IADT)
in the Treatment of Prostate Cancer (PCa)
after Biochemical Failure
W. Mermershtain, Y. Zalcberg, K.Rouvinov, I.Gusakova, S.Ariad
Department of Oncology, Soroka University Medical Center, and Faculty of
Health Science, Ben-Gurion University of the Negev, Beer-Sheva, Israel
Background: Androgen-deprivation therapy (ADT) has progressed since 1941 when surgical
castration was shown to improve PCa outcomes. Gonadotropin-releasing hormone agonists were
discovered in 1971 and are now the mainstay of PCa treatment. The well-known side effect profile
of ADT has significant quality-of-life (QoL) implications such as sexual dysfunction, hot flushes,
and fatigue. The strategy behind IADT, therefore, is to alternate androgen blockade with treatment
cessation, allowing hormonal recovery between treatment periods.
Objective: To evaluate the efficacy and tolerability of IADT and assess its value in the
treatment of PCa.
Material and Methods: 65 PCa pts previously treated with Radical Prostatectomy, EBRT, or BT
with biochemical failure were treated with IADT. Treatment included Bicalutamide 50mg/d, days 128 and one injection of LHRH–agonist (usually Suprefact depot 9.9mg or Zoladex 10.8mg). The
average age was 76 years (range 62-86). The average follow-up time was 39.5 months (range 4-80).
Results: The average interval to biochemical failure was 15.4, 14.1 and 12.3 months for the
first, second and third relapses, respectively. The average PSA serum level before IADT was
4.08ng/ml; at first nadir - 0.15ng/ml, at first and second re-initiation - 1.8ng/ml, - 2.7ng/ml, and at
first and second nadirs - 0.21ng/ml and 0.29ng/ml, respectively. Total testosterone serum levels
between treatment cycles (randomly investigated in 50% of pts) were normalized in many, but
not all patients.
Conclusion: IADT is a valid treatment option in non-metastatic PCa patients with locally
advanced disease, and improves QoL during off-therapy periods.