1. Patients who cannot lie still for at least 30 minutes or comply with imaging.
2. Previous dasatinib for prostate cancer or other condition, eg CLL
3. Allergy to dasatinib or darolutamide
4. Use of drugs that interact with interact pharmacologically with dasatinib within 1 week of study entry eg Use of CYP3A4 inducers (e.g. dexamethasone, phenytoin, carbamazepine, rifampicin, phenobarbital or St John's Wort) and use of CYP3A4 substrates with narrow therapeutic index (e.g. astemizole, terfenadine, cisapride, pimozide, quinidine, bepridil or ergot analogues.
5. Use Concomitant use of H2 antagonists or proton pump inhibitors.
6. Current or previous (within the last 6 months) pleural effusion
7. Use of paracetamol during the study period
8. Subjects may not have any of the following: Clinical evidence of uncontrolled heart failure, myocardial infarction, or angina within the previous 6 months; prolonged QT interval Fridericia's (QTcF) > 450msec; history of unstable ventricular arrhythmias (ventricular tachycardia, ventricular fibrillation, or torsades de pointes); concomitant use of drugs known to cause torsades de pointes [quinidine, procainamide, disopyramide, amiodarone, sotalol, ibutilide, dofetilide, erythromycins, clarithromycin, chlorpromazine, haloperidol, mesoridazine,thioridazine, pimozide, cisapride, bepridil, droperidol, methadone, arsenic, chloroquine, domperidone, halofantrine, levomethadyl,pentamidine, sparfloxacin, lidoflazine] (these agents must have been discontinued at least 7 days prior to starting dasatinib)
9. Subjects may not be enrolled with any of the following: History of a significant bleeding disorder unrelated to cancer, including diagnosed congenital bleeding disorders (e.g., von Willebrand's disease), and diagnosed acquired bleeding disorder within one year (e.g., acquired anti-factor VIII antibodies); GI bleeding from any cause within 3 months