Comparison of transrectal ultrasound and magnetic resonance imaging in the staging of prostate cancer.

A group of 32 patients with a histological diagnosis of prostate cancer underwent transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) to stage the disease. TRUS was more sensitive in the detection of tumour and in the detection of direct extracapsular spread. MRI was more sensitive in the detection of tumour involvement of the seminal vesicles and bladder base. MRI allowed the detection of lymphadenopathy and bone metastases in the lumbosacral spine and pelvis. During MRI the short tau inversion recovery (STIR) sequence was found to be particularly useful for the detection of tumour spread. TRUS and MRI are complementary investigations and for the accurate staging of prostatic malignancy both investigations should be used.