3TMPO (Triple-Tracer Strategy Against Metastatic Prostate Cancer

Inclusion Criteria:

1. Male ≥ 18 years old
2. Histologically or cytologically proven PCa with or without neuroendocrine differentiation at initial diagnosis
3. Castration-resistant prostate cancer with serum testosterone ≤ 50 ng/dL (1.73 nM) anytime while on androgen deprivation therapy
4. Evidence of disease progression on prior therapy or watchful waiting. Disease progression is defined by meeting at least one of the following criteria:

   1. PSA progression defined by a minimum of 2 consecutive rising PSA levels with an interval of ≥1 week between each assessment where the PSA value at screening should be ≥1ng/ml.
   2. Soft tissue disease ONLY progression\* defined by RECIST 1.1: 1) at least 20% increase in the diameter of target lesions and 2) an absolute increase of ≥ 5 mm of the sum.
   3. Soft tissue disease ONLY progression\* defined as the appearance of at least one new lesion (soft tissue).
   4. Bone disease ONLY progression\* defined by two or more new lesions on bone scan.
5. Metastatic disease documented by at least 3 active lesions on whole body bone scan and/or measurable soft tissue on CT-scan (lymph nodes and visceral lesions). Metastatic lesions on imaging are defined by RECIST 1.1, either:

   * ≥ 10 mm on CT scan or caliper (for lymph nodes, see below)
   * ≥ 20 mm on chest X-ray
   * lymph node ≥ 15 mm or ≥ 10 mm and having grown by ≥ 5 mm from baseline CT
   * any metastasis described on bone scan counts as a lesion
6. Able and willing to provide signed informed consent in French or English and to comply with protocol requirements.

Exclusion Criteria:

1. Another non-cutaneous malignancy or melanoma diagnosed in the past 5 years;
2. Currently under a randomized-controlled trial with unknown allocation;
3. Limited survival prognosis (ECOG ≥3);
4. Patients under dialysis;
5. Any disease or condition limiting the patient's capacity to execute the study procedures, based on the investigators' opinion.