Assessment of the bone scan index in a randomized placebo-controlled trial of tasquinimod in men with metastatic castration-resistant prostate cancer (mCRPC)1A.J.A. and R.K. contributed equally to this work.

Abstract

BSI and BSI changes over time were independently associated with OS in men with mCRPC. A delay in objective radiographic bone scan progression with TASQ is suggested; prospective evaluation of BSI progression and response criteria in phase 3 trials of men with mCRPC is warranted.

Analytic Validation of the Automated Bone Scan Index as an Imaging Biomarker to Standardize Quantitative Changes in Bone Scans of Patients with Metastatic Prostate Cancer

“…Variables such as image count corresponding to scanning time and interpatient-dependent attenuation factors can cause noise in BSI interpretations, and this noise can affect the reliability of the on-treatment BSI change as a quantitative biomarker. In previous studies, the on-treatment BSI change has been reported as the percentage of BSI change, BSI doubling time, and BSI difference (5,14,15), but none of the studies have accounted for the noise in BSIs that results from the inherent variability of the bone scan procedure.…”

Validation of the Association of RECIST Changes With Survival in Men With Metastatic Castration-Resistant Prostate Cancer Treated on SWOG Study S0421

“…It is noteworthy that tasquinimod did not yield an extension of OS in a phase III trial despite an improvement in BSI and radiographic progression-free survival in preceding phase II trials. 27–29 Additionally, multiple phase III trials combining docetaxel with biologic agents have not demonstrated increments in survival despite preliminary evidence for benefits mostly in terms of PSA and bone scan changes (and not RECIST changes) in preceding phase II trials. 4–8, 30 Indeed, the phenomena of early PSA spikes coupled with the probability of early bone scan flares, prompted the PCWG to recommend a minimum of 12 weeks of therapy before making clinical decisions regarding continuation of a regimen.…”

Integration of Bone and Computed Tomography Scans to Assess Bone Metastasis in Metastatic Castration-Resistant Prostate Cancer

“…Indeed, despite an improvement in BSI and radiographic PFS (which mostly consisted of BS progression) with tasquinimod (an investigational antiangiogenic and immune-modulating drug), this agent did not yield an extension of OS in a phase III trial. [18][19][20] Bone-directed positron-emission tomography imaging using new radiolabeled tracers such as sodium fluoride, fluorothymidine, choline, and prostate-specific membrane antigen also only provide an indirect measure of tumor burden and might be limited by the flare response and/or costs. [21][22][23][24][25][26][27][28] Magnetic resonance imaging might have better sensitivity and specificity than BS but suboptimal whole-body coverage and costs are again limitations.…”

“…The data set with appropriate imaging and follow-up included 28 patients evaluable for the primary analysis with 18 Tables 1 and 2. The mean (standard deviation) age of these patients was 71.4 (9.8) and 13 of 26 (50.0%) with available data had Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 1, with the remaining 13 (50%) having an ECOG PS of 0.…”