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Purpose: The aim of this work was to assess the accuracy of kilovoltage (kV) cone-beam computed tomography (CBCT)–based setup corrections as compared with orthogonal megavoltage (MV) portal image-based corrections for patients undergoing external-beam radiotherapy of the prostate. Methods and Materials: Daily cone-beam CT volumetric images were acquired after setup for patients with three intraprostatic fiducial markers. The estimated couch shifts were compared retrospectively to patient adjustments based on two orthogonal MV portal images (the current clinical standard of care in our institution). The CBCT soft-tissue based shifts were also estimated by digitally removing the gold markers in each projection to suppress the artifacts in the reconstructed volumes. A total of 256 volumetric images for 15 patients were analyzed. Results: The Pearson coefficient of correlation for the patient position shifts using fiducial markers in MV vs. kV was (R2 = 0.95, 0.84, 0.81) in the left–right (LR), anterior–posterior (AP), and superior–inferior (SI) directions, respectively. The correlation using soft-tissue matching was as follows: R2 = 0.90, 0.49, 0.51 in the LR, AP and SI directions. A Bland-Altman analysis showed no significant trends in the data. The percentage of shifts within a ±3-mm tolerance (the clinical action level) was 99.7%, 95.5%, 91.3% for fiducial marker matching and 99.5%, 70.3%, 78.4% for soft-tissue matching. Conclusions: Cone-beam CT is an accurate and precise tool for image guidance. It provides an equivalent means of patient setup correction for prostate patients with implanted gold fiducial markers. Use of the additional information provided by the visualization of soft-tissue structures is an active area of research. [Copyright &y& Elsevier]

Choroidal metastases secondary to urothelial carcinoma are extremely rare and are usually associated with an extremely poor prognosis. We present a case of an 88-year-old man with newly diagnosed urothelial carcinoma of the bladder who presented with acute loss of vision before commencing definitive concurrent chemoradiotherapy to the bladder. Ophthalmological examination demonstrated bilateral choroidal metastases. He received palliative radiotherapy to the orbits and completed his planned radiotherapy to the bladder. He remained disease-free at last follow-up 4 years after the completion of treatment. We review the literature particularly with regard to diagnosis and management of choroidal metastases. Choroidal metastases should be considered in a patient with a history of urothelial cancer presenting with new onset of eye symptoms.