Beyond haematuria in uro oncology: imaging biomarkers lag behind needs

Abstract

Haematuria is the presence of red blood cells in the urine, and it is an important symptom in the diagnosis and treatment of renal and urological disease. Haematuria, which can be suspected on the basis of urine colour, is confirmed by the use of qualitative and/or semiquantitative urine strips to test for occult blood and by microscopic examination of urine sediment. Haematuria can be either microscopic or gross. Microscopic haematuria is the finding of more than three red blood cells per high-powered field in at least two out of three different urine samples collected at different times, whereas gross haematuria is the term used when blood present in urine is visible to the naked eye. Haematuria can originate from the kidneys or urinary tract and bladder [1]. A prospective analysis of the diagnostic yield from over 4,000 patients attending a protocol-driven haematuria clinic demonstrated that 1,950 (48.5%) had microscopic haematuria and 2,073 (51.5%) had macroscopic haematuria. Of the 1,950 patients with microscopic haematuria, 153 (7.8%) had urinary tract calculi, 19 (1.0%) had renal cell cancer (RCC), 3 (0.2%) had upper tract transitional cell cancer (TCC), 73 (3.7%) had bladder TCC, while 87.3% had no detectable cause of the haematuria. The overall prevalence of malignancy in patients with microscopic haematuria was 4.8%. Of the 2,073 patients with macroscopic haematuria, 183 (8.8%) had urinary tract calculi, 41 (2.0%) had RCC, 10 (0.5%) had upper tract TCC, 342 (16.5%) had bladder TCC, while 1,497 (72.2%) had no identifiable cause of their haematuria [2]. Most RCCs are discovered incidentally during CT imaging performed for other reasons. Around 70% of renal cortical tumours are confined to the kidney and 30% will develop into metastatic disease at some time during their course. Of these tumours, one in four will be benign, another one in four will be indolent (with limited metastatic potential), and approximately two in four will be malignant carcinomas. As reported by O’Connor et al. of the Department of Radiology, Cork University Hospital, Republic of Ireland [3], RCC is the most common malignant neoplasm of the kidney, accounting for up to 90% of renal neoplasms and up to 3% of all neoplasms. It is more common in men than in women (3:2 ratio), has a peak incidence between 60 and 70 years of age, and is associated with smoking, obesity, and antihypertensive therapy. TCC accounts for 10% of upper urinary tract neoplasms. Although TCC is most likely to occur in the bladder, the ureters have been reported to be involved in 2%, and the renal pelvis in 5% of patients. TCC may also have a multifocal presentation. Synchronous tumours occur in up to 2% of renal and 9% of ureteric lesions, with metachronous lesions typically occurring in the bladder in up to 50% of patients with upper ureteric tumours on presentation. Imaging is required for primary diagnosis of TCC and is commonly used for the detection of synchronous and metachronous lesions. Bladder neoplasia is the fifth most common cancer in Europe and the fourth most common in the United States. TCC of the bladder also occurs more commonly in men than in women, is associated with smoking (incidence up to fourfold greater than in nonsmokers), exposure to chemicals such as benzene and 2