This study aims to identify patients with low-risk prostate cancer (ISUP Grade Group 1) eligible for active surveillance who are at higher risk of upgrading to ISUP Grade Group 2 or higher at confirmatory biopsy one year after diagnosis. Patients with low-risk ISUP GG1 tumors will be selected and undergo:

• PSMA PET with calculation of SUVmax and PRIMARY-Likert score
• Whole Exome Sequencing (WES) analysis on diagnostic prostate biopsies
• Immunohistochemistry on diagnostic prostate biopsies
• Confirmatory biopsy one year after diagnosis, as recommended by international guidelines This prospective, monocentric, single-arm interventional study will assess the predictive accuracy of a multivariable model integrating next-generation imaging and molecular biomarkers to improve risk stratification in active surveillance patients.

Inclusion Criteria:

• Histologically proven low-risk PCa (PSA ≤10 ng/ml; clinical stage ≤T2a, and biopsy ISUP GG 1)
• Non-metastatic status at study inclusion (patient enrollment).
• No prior or concomitant androgen deprivation therapy
• Ability to understand a written informed consent and willingness to sign it.

Exclusion Criteria:

• Unable to tolerate a PSMA-PET scan
• Unwillingness to be managed with AS
• Receipt of neoadjuvant or curative-intent therapies
• Pacemaker
• Inability to obtain the FFPE prostate biopsy specimens from the initial biopsy