Octreoscan (O) and cold somatostatin-analogue effectiveness in advanced androgen deprivation refractory prostate cancer (ADPRC)

Abstract

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Objectives: To assess neuroendocrine features of ADRPC lesions and to relate O results with therapeutical effect of SA, we submitted 32 patients (pts) with ADPRC to O study. All pts had CT or Bone scan-proven bone, lymph-nodal or parenchimal metastases.

Methods: All pts were intravenously injected with 185 MBq of 111In-Pentetreotide. 4, 24 and 48 hours whole body and abdomen and pelvis O SPECT scan were obtained. SPECT were reconstructed by OSEM method (6 iterations). Performance status and bone pain, together with CgA and PSA serum levels were evaluated at baseline and after 3 months of SA therapy.

Results: CgA was elevated in 20/32 pts, whereas PSA in 26/32 pts. 13/32 pts had elevation of both markers and O scan resulted positive in all of them. O scan was positive in 25/32 pts, of whom 19 had CgA elevation and 21 PSA increase. 14/16 bone metastatic pts showed O uptake. O showed pathological findings in 6/7 liver metastatic pts, 3/5 lung metastatic pts, 1/3 pancreatic metastatic pts, 4/11 loco-regional lymph-nodes and 8/11 extra-regional lymph-nodes metastatic pts. Only a limited number of metastatic areas were characterized by SA uptake. Worth of note, the extension of O positive foci does not correlates with CgA levels. 4 pts experienced pain relief and/or performance status improvement after 3 months of SA therapy. Although O positive scans as well as serum markers levels alone were not predictor of SA responsiveness, all pts SA responders showed O positive scan and both high serum CgA and PSA levels.

Conclusions: O scan characterized prostate cancer metastatic lesions, expressing SA receptors. SA therapy responders presented association between O scan positivity and high serum levels of both PSA and CgA.