Zhao Qingli, Department of Urology, Shandong Qianfo Mountain Hospital: Prostatic intraepithelial neoplasia (PIN) refers to neoplastic changes in the lining epithelium of the prostate ducts and alveoli. This neoplasm is confined to the epithelial layer, hence the name intraepithelial neoplasm. Most studies have shown that high-grade PIN in puncture biopsy tissue is a high risk factor for subsequent detection of prostate cancer, while low-grade PIN is not. The detection rate of prostate cancer in secondary biopsies after a diagnosis of HGPIN in puncture biopsy tissue is approximately 30%. In comparison, the detection rate of prostate cancer was 20% in secondary biopsies after a diagnosis of benign prostate tissue and 16% in secondary biopsies after a diagnosis of low-grade PIN. After the diagnosis of HGPIN, most (80% to 90%) prostate cancers are detected on the first subsequent repeat biopsy. Repeat biopsies can re-detect HGPIN in 5% to 43% of cases. HGPIN with an atypical gland in the immediate vicinity has a greater risk of subsequent diagnosis of prostate cancer than HGPIN alone, with a mean detection rate of 53% for prostate cancer. Therefore, all men with this lesion should have a repeat biopsy. Serum PSA interest is inconclusive. There are no consistent data on whether the extent and histologic form of HGPIN may indicate the risk of subsequent detection of prostate cancer, and genetic abnormalities and/or immunophenotypes of HGPIN have not been used to determine the magnitude of the risk of subsequent detection of prostate cancer. The current general principle is to recommend that patients with isolated HGPIN should be re-biopsied within 0-6 months regardless of serum PSA levels and rectal exam findings. However, these principles may be changed in cases where there is HGPIN in the biopsy specimen but the associated data do not suggest a high risk indicator for prostate cancer. At least a systematic 6-point biopsy of the entire prostate should be performed when biopsied again, because HGPIN usually has high-risk indicators of prostate cancer throughout the prostate. Zhao Qingli, Department of Urology, Shandong Province Qianfo Mountain Hospital