The Evolving Role of Shear Wave Elastography in the Diagnosis and Treatment of Prostate Cancer

To forego misdiagnosis and biopsy-related complications, we explore a novel technique that embraces tissue elasticity to circumvent the current limitations in the accurate, non-invasive detection of prostate cancer. A MEDLINE® database search of literature pertinent to prostate elastography published in the last five years was guided using the following terms: tissue elasticity, ultrasound elastography, strain elastography, magnetic resonance elastography, and shear wave elastography. Ultrasound shear wave elastography (SWE) utilizes the propagation of induced shear waves to provide a quantitative measurement of elasticity of soft tissue. Studies attempting to prove SWE as a strong predictor of malignant prostatic tissue have validated its high specificity and sensitivity compared to the sub-50% range observed with magnetic resonance imaging or transrectal ultrasound. Because its median positive predictive value is also much higher than the sub-40% range attributed to more conventional techniques, SWE yields reduced false-negative biopsy rates. It furthermore exhibits higher intraobserver reproducibility compared to conventional ultrasound. Recent treatments have also utilized SWE for noninvasive prostate cancer tissue ablation. Future improvements include standardized cutoff ranges for quantifying elasticity of malignant tissue. The implementation of a scoring system to predict cancer aggressiveness and prognosis may eliminate the need for unwarranted repeat biopsies postdiagnosis.