Autor: |
E J, Small, D M, Reese, B, Um, S, Whisenant, S C, Dixon, W D, Figg |
Rok vydání: |
1999 |
Předmět: |
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Zdroj: |
Clinical cancer research : an official journal of the American Association for Cancer Research. 5(7) |
ISSN: |
1078-0432 |
Popis: |
Granulocyte macrophage colony-stimulating factor is a pleiotropic cytokine capable of inducing systemic immune responses against experimental and human tumors. To evaluate the efficacy of GM-CSF treatment in patients with hormone-refractory prostate cancer, we conducted sequential Phase II studies in 36 men with progressive disease after androgen deprivation and antiandrogen withdrawal. In a first cohort of patients (n = 23), GM-CSF was administered s.c. at a dose of 250 microg/m2 daily for 14 days of a 28-day treatment period. After we observed oscillating prostate-specific antigen (PSA) responses in several patients in this first cohort, a second trial was performed in which patients (n = 13) received maintenance GM-CSF (250 microg/m2 three times weekly) after the first 14 days of daily GM-CSF. All patients were treated until disease progression. Response was assessed by evaluation of serial changes in serum PSA and sequential imaging studies. In cohort I, 10 of 22 patients (45%) had a PSA versus time plot with a sawtooth pattern, with PSA declining during GM-CSF therapy and climbing during the off-therapy period; 5 patients had at least two consecutive declines in PSA, with a median response duration of 3.5 months. All but one patient in cohort II experienced a decline in PSA (median decline, 32%), but a PSA decline greater than 50% and sustained for more than 6 weeks was seen in only one patient, who had a99% decline in PSA and an improvement in bone scan lasting for 14+ months. Changes in PSA levels could not be attributed to direct or indirect effects of GM-CSF on the PSA assay or down-regulation of PSA expression by GM-CSF. Toxicity was very mild, consisting primarily of transient constitutional symptoms and injection site reactions. These data suggest that GM-CSF may have antitumor activity in advanced prostate cancer, and the use of GM-CSF may be a confounding variable when PSA responses are used as an end point in clinical trials evaluating new regimens for the treatment of advanced prostate cancer. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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