Factors Predicting the Prolonged Duration of Off-treatment in Intermittent Androgen Deprivation of Prostate Cancer Treatment / 대한비뇨기과학회지

ABSTRACT

PURPOSE: The goal of intermittent androgen deprivation (IAD) therapy in prostate cancer patients is to delay the disease progression and improve the survival rate. Therefore, the duration of off-treatment is very important for the effective treatment outcome of IAD. We analyzed factors that influence the duration of off-treatment in IAD. MATERIALS AND METHODS: We reviewed the medical records of 45 patients with prostate cancer who had completed at least 1 cycle of IAD. Uni- and multi-variate tests were used to determine the factors, which are predictive to the duration of off-treatment. These factors included the patient's age, biopsy Gleasons score, initial PSA, presence of bone metastasis, PSA levels at 3 months following on-treatment and at 3 months following off-treatment, and the duration of on-treatment. RESULTS: The average follow up duration was 34 months (15-71 months). The average off-treatment duration of each cycle was 11.1 (4-40), 7.5 (4-14), and 5.6 (3-10) months for the 1st, 2nd and 3rd cycles, respectively. Independent factors associated with the extension of duration of off-treatment, by univariate tests, included initial PSA value, PSA values at 3 months following on-treatment, PSA at 3 months following off- treatment, and duration of on-treatment. The duration of off-treatment was inversely related to the serum PSA level at the start, 3 months following on-treatment, and 3 months following off-treatment, while it was directly related to the duration of on- treatment by multivariate tests. CONCLUSIONS: The pretreatment serum PSA level and the serum PSA level at 3 months following on-treatment and off-treatment were valuable predictors for the duration of off-treatment in IAD.