Question

A primary care physician refers a $65$-year-old retired chemical worker to the urology service due to alarming urinary changes. Over the preceding four weeks, the patient noted three distinct episodes where his entire urinary stream was bright red. He reports no associated pain during urination, flank discomfort, fever, or weight loss. He has a history of essential hypertension and smoked one pack of cigarettes daily for $40$ years before quitting recently. In the clinic, his vital signs are stable. Examination of the abdomen and external genitalia shows no abnormalities, and digital rectal examination reveals a smooth, non-enlarged prostate. A catheter-free urinalysis demonstrates $>50$ red blood cells per high-power field, with absent leukocyte esterase. A multiphasic computed tomography urogram is subsequently performed, which outlines normally functioning kidneys and pristine ureters without any solid masses or nephrolithiasis. Which of the following is the most appropriate next step in management?