UroToday.com- Docetaxel chemotherapy is associated with improved survival in men with androgen-independent prostate cancer (AICaP). In the Taxotere Study 327 men, 46% of patients treated on a schedule of every 3 weeks, were able to complete the planned initial course of chemotherapy without disease progression or unacceptable toxicity. In the journal Cancer, Dr. Beer and investigators report on data from the ASCENT trial (AICaP Study of Calcitriol Enhancing Taxotere) that suggests that some patients are candidates for intermittent application of chemotherapy.
The ASCENT trial design incorporated intermittent chemotherapy for selected patients. Men with chemotherapy-naïve, metastatic AICaP were treated with calcitriol (45g) or placebo followed by docetaxel with dexamethasone administered weekly for 3 consecutive seeks of a 4-week cycle. Treatment was continued until disease progression, unacceptable toxicity, or patient request. Intermittent chemotherapy was an option for patients who reached a PSA level <4.0ng/ml and it was resumed when the PSA level rose by 50% and was >2.0ng/ml, or other evidence of disease progression.
A total of 45 of 250 patients (18%) were eligible and participated in the intermittent protocol. Of these, 20% of patients were treated with high-dose calcitriol and 16% were treated with placebo in combination with docetaxel. Eligible patients began chemotherapy after a median of 22 weeks. Of the 45 patients, 38 completed the first treatment holiday and 36 were retreated. At last follow-up, 7 patients remained on a treatment holiday. The median duration of the first chemotherapy holiday was 18 weeks (20 weeks for those on calcitriol and 16 weeks for placebo treated patients). Thirty-three of the 36 participants who resumed treatment after an initial treatment holiday were evaluable for PSA response and 15 of these responded with a >50% reduction in the serum PSA from their post-holiday baseline. Fifteen patients also met the criteria for stable PSA for at least 12 weeks and 3 patients had disease progression.
This is the first study reporting on intermittent chemotherapy in patients with AICaP and suggests that it can be offered selectively.
Beer TM, Ryan CW, Venner PM, Petrylak DP, Chatta GS, Ruether JD, Chi KN, Young J, Henner WD, On Behalf of the ASCENT (AIPC Study of Calcitriol Enhancing Taxotere) Investigators