Long-Term Survival and PSA Control with Radiation and Immunotherapy for Node Positive Prostate Cancer

Table 1

ELISPOT PSA-specific T cells for patients with node positive disease at various time points during vaccination. Patient 1 is the only patient with detectable PSA-specific T cells prior to starting vaccination. It should be noted that the post-4 immune responses were obtained mid-radiation, and unlike the other time points, this blood was prepared from a peripheral blood draw rather than an apheresis sample. Interestingly, radiation has been shown to upregulate markers on the tumor facilitating tumor specific T-cell trafficking which may impact peripheral circulation of antigen specific T-cells (reviewed in [4]). It is possible that either of these variables could have impacted the measured immune response. *Post-2 cycles.

Time Point	Patient 1	Patient 2	Patient 3	Patient 4
Pre-vaccine	1/50,000	1/200,000	<1/200,000	1/150,000
Post-3 cycles	1/37,500	1/54,545	1/50,000	<1/200,000^∗
Post-4 cycles	<1/200,000	<1/200,000	<1/200,000	Data not available
Post-5 cycles	1/24,000	1/66,667	<1/200,000	1/12,000
Post-8 cycles	1/15,789	1/22,222	1/46,154	Data not available