Participants to the study will be assigned to 7 cohorts according to the stage of disease and planned antitumor treatment at time of study entry.

In all patients, 12 ml of blood sample will be collected in EDTA tube for analysis of biological biomarkers in different time points.

Participants to the study will be assigned to 5 cohorts according to the stage of disease and planned antitumor treatment at time of study entry.

Group 0 (set-up): blood sampling and rectal swab will be collected at a single time-point during the PC treatment. No follow-up is required.

Group 1a (control): the first blood sampling will be performed within 4 weeks since the negative biopsy; subsequent samplings will be done according to a schedule comparable to that of Group 1 up to 1 year or evidence of tumor, whichever occurs first.

Group 1, Group 2 and Group 3: the first blood sampling will be performed before radical treatment or HT start or CT start, on the basis of the planned antitumor therapy; subsequent sampling will be done after radical intervention at 4 weeks (only for Group 1) and then every 3 months (or more frequently if clinically indicated), up to 3 years or evidence of tumor recurrence/progression (radiological or biochemical), whichever occurs first.

At the time of recurrence/progression, patients of Group 1 could become part and could be followed as per Group 2, and patients of Group 2 could become part and could be followed as per Group 3.

Group Exo and Group Bio: blood sampling will be performed at a single time-point during the PC treatment. No follow-up is required.

Inclusion Criteria:

General inclusion criteria (for entering all groups)

• Age ≥ 18 years
• Histological diagnosis of prostate adenocarcinoma at different stages of disease (see Section 6.2) for which a treatment is indicated
• Written Informed Consent

Inclusion criterion only for entering Group 0

• Patients with a known diagnosis of CSPC or CRPC

Inclusion criterion only for entering Group 1a

• Patients that underwent biopsies for a suspect of PC, but resulted negative for cancer

Exclusion Criteria:

General exclusion criteria (for entering all groups)

• Active infection requiring treatment
• Decrease of general condition
• Concomitant severe comorbities
• Difficult socioeconomic conditions making regular follow up unfeasible.
• Need of concomitant steroids at study entry and during the study
• Diagnosis of second tumor in the previous 5 years

Exclusion criterion only for entering Group 0

• No antibiotic treatments in the previous 2 months before enrollment

Exclusion criteria only for entering Group 1

• Previous radical surgery and / or radical radiotherapy
• Previous hormonal treatments

Exclusion criteria only for entering Group 2

• No antibiotic treatments in the previous 2 months before enrollment (only in patients enrolling also for metagenomics and metabolomics)
• Previous hormonal treatments for advanced disease

Exclusion criterion only for entering Group 3

• No antibiotic treatments in the previous 2 months before enrollment (only in patients enrolling also for metagenomics and metabolomics analyses)

Patients with prostate adenocarcinoma at different stages of disease