Inclusion Criteria:

- Histologically proven diagnosis of prostate cancer

- Evidence of PSA progression despite castrate levels of testosterone (<50 ng/dL)
following orchiectomy or during therapy with luteinizing hormone releasing hormone
agonists (LHRH-a)

- Patients with non-metastatic or stable metastatic disease

- Chromogranin A elevation above normal range (confirmed by a second evaluation at
least 1 week later) [cut off levels will be > 20 U/L for enzyme linked immunosorbent
(ELISA) assay and > 100 ng/ml for immunoradiometric (IRMA) assay]

Exclusion Criteria:

- Patients who according to the investigator opinion are candidates to be treated
immediately with chemotherapy (e.g. docetaxel)

- First line treatment with antiandrogen in monotherapy

- Visceral metastasis

- Previous or concomitant treatment with a somatostatin analogue