—It is well known that TRUS is neither sensitive nor specific in identifying prostatic cancer. Approximately one half of prostatic cancers greater than 1 cm in diameter are not visualized on TRUS and only 15% of hypoechoic lesions turn out to be cancer.1 These observations are further confirmed by our study that demonstrated that TRUS was not predictive of whether tumor was significant or insignificant. Furthermore, investigators at the Mayo Clinic also have shown that there is no difference in tumor extent whether a lesion was visualized or not visualized on TRUS.2 The rationale for the current TNM staging is not clear. We hope this issue will be reevaluated based on the evidence presented above, and in the future TRUS upstaging of nonpalpable lesions will be eliminated from this classification.
Epstein JI, Walsh PC, Carmichael M, Brendler CB. Use of Transrectal Ultrasound to Stage Prostate Cancer-Reply. JAMA. 1994;272(7):516-517. doi:10.1001/jama.1994.03520070034025