This document discusses high-grade prostatic intraepithelial neoplasia (HGPIN) and other proposed pre-cancerous lesions in the prostate. HGPIN is considered the lesion most strongly associated with increased risk of later prostate cancer. The review discusses the morphological spectrum and clinical importance of these lesions, particularly HGPIN. Evidence from various studies indicates HGPIN is more closely related to prostate cancer than benign prostate tissue.

1. Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Rodolfo Montironi, Roberta Mazzucchelli, Antonio Lopez-Beltran, Liang Cheng and Marina Scarpelli Nature Clinical Practice Urology (2007) 4 , 321-332 doi:10.1038/ncpuro0815 Nature Clinical Practice Urology (2007) 4 , 321-332 doi:10.1038/ncpuro0815 Nature Clinical Practice Urology (2007) 4 , 321-332 doi:10.1038/ncpuro0815

2. Summary Various findings in prostate tissue indicate raised risk of later prostate cancer, and, of all these, the finding of high-grade prostatic intraepithelial neoplasia on repeated biopsy is most strongly associated. This Review discusses the morphologic spectrum and clinical importance of these proposed preneoplastic lesions and conditions of the prostate, especially high-grade prostatic intraepithelial neoplasia.

3. Figure 1 Morphological spectrum for normal prostate to high-grade prostatic intraepithelial neoplasia Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815

4. Figure 2 High-grade prostatic intraepithelial neoplasia with neuroendocrine differentiation Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815

5. Figure 3 Atypical basal-cell hyperplasia (adenosis) Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815

6. Figure 4 Adenocarcinoma originating from high-grade prostatic intraepithelial neoplasia Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815

7. Figure 5 The effect of androgen ablation on high-grade prostatic intraepithelial neoplasia Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815

8. Figure 6 Focal atrophy with high-grade prostatic intraepithelial neoplasia and adenocarcinoma Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815

9. Table 1 Risk of detection of carcinoma on needle core repeat biopsy Montironi R et al . (2007) Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate Nat Clin Pract Urol 4: 321 – 332 doi:10.1038/ ncpuro0815