Differentiation of prostate cancer from benign lesions using strain index of transrectal real-time tissue elastography

• Published in: European journal of radiology 2012-05, Vol.81 (5), p.857-862
• Main Authors: Zhang, Yan, Tang, Jie, Li, Yan-mi, Fei, Xiang, Lv, Fa-qin, He, En-hui, Li, Qiu-yang, Shi, Huai-yin
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Algorithms; Computer Systems; Diagnosis, Differential; Elastic Modulus; Elasticity Imaging Techniques - methods; Elastography; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Male; Middle Aged; Prostatic neoplasm; Prostatic Neoplasms - diagnostic imaging; Prostatic Neoplasms - physiopathology; Radiology; Rectum - diagnostic imaging; Rectum - physiopathology; Reproducibility of Results; Sensitivity and Specificity; Strain index; Ultrasound
• ISSN: 0720-048X; 1872-7727
• DOI: 10.1016/j.ejrad.2011.02.037

Abstract Objective This study was to assess the diagnostic value of strain index (SI) for transrectal real-time tissue elastography (TRTE) on differentiating malignant from benign lesions in the prostate peripheral zone. Methods 83 patients suspected of having prostate cancer (PCa) underwent transrectal ultrasonography (TRUS) and TRTE examinations. The lesions in the prostate peripheral zone detected by TRTE were set as the regions of interest (ROI) for strain ratio (SR) measurement (SRA). The moderate texture tissues without lesion were set as the reference ROI for SR measurement (SRB). Then, SI (SRB/SRA) of total lesions (ASI) and local lesion (PSI) were calculated, and the diagnostic values of ASI and PSI on differentiating benign from malignant lesions were assessed respectively. Results The range of PSI was 2.23–67.21 (29.97 ± 15.58) in malignant tumors and 0. 4–43.6 (7.79 ± 8.75) in benign lesions (AUC = 0.90), while the range of ASI was 2.84–47.9 (8.38 ± 12.20) in malignant tumors and 0.4 –2.79 (5.85 ± 7.29) in benign lesions (AUC = 0.62). There was significant difference of PSI values between the benign and malignant lesions ( P < 0.01). At the cutoff value of 17.44, PSI yielded the highest sensitivity (74.5%) and specificity (83.3%) for discriminating PCa from benign lesions. The capability of PSI in the diagnosis of PCa improved with the increase of Gleason scores. Conclusion PSI is one of the elasticity parameters obtained easily by TRTE, it can provide more information in the differentiation of prostate peripheral zone lesions.