Introduction:

Taxotere remains a common treatment modality for metastatic castrate resistant prostate cancer (mCRPC). Little data exists on the predictive value of C-11 choline PET following treatment with taxotere. We sought to investigate whether evaluation of patients with C-11 choline PET scan after a full course of taxotere was predictive of progression free-survival.

Methods:

We retrospectively identified 77 mCRPC patients who were treated with a full course of 6 cycles of taxotere and were evaluated with a C-11 choline PET scan before treatment and after full course of taxotere chemotherapy between 2011-2017. Patients receiving or have received prior second generation ADT or prior chemotherapy were excluded. Complete response was defined as complete SUV resolution of the index lesion and a PSA nadir of ≤0.2 ng/ml following completion of a full taxotere course.

Results:

A table of clincopathologic variables is seen in Table 1. Median progression- free survival was 33.97 months (95% CI 26.02 - 38.57) in complete response group versus 9.53 months in incomplete response group (95% CI 5.09 - 11.49, p=0.001). Progression-Free survival is seen in Figure 1. Patients who respond incompletely to a full course of taxotere, have 2.4 times risk of developing progressive disease than patients who respond completely (p=0.001).

Conclusion:

Predicting progression-free survival after treatment for mCRPC is a challenging endeavor. We provide our experience with C-11 choline PET scan to help guide post-taxotere treatment counseling. Patients with incomplete response, either biochemically or radiographically on C-11 Choline PET, after full course of taxotere treatment are at significantly higher risk or disease progression and may benefit from a change in treatment modality or combination therapy.

Funding: NA