Thanks for sharing your amazing deep knowledge of these assays. My level went from 1750 to 575, two different labs, one was at Quest and the second was at Sloan Kettering Memorial Cancer Center. I have had three cycles of chemo. The drop in CA 19-9 was an indicator that my current treatment was effective. For treatment of BRCA1 associated pancreatic cancer, they favor oxy platinum and gemcitabine as initial treatment but if the oxy platinum and 5-FU show good effect, to continue current treatment. The CT scan also showed some early benefit and the recommendation to continue current treatment. The side effects seem very manageable and I was glad not to have to change and have different side effects. I will have a reevaluation after 7-8 cycles of treatment to see if I have changed from borderline removable to being a surgical candidate.