Neuroendocrine differentiation in castration-resistant prostate cancer: A case report

Abstract

Abstract. The most common type of prostate cancer is acinar adenocarcinoma, which is androgen-dependent and, therefore, treated with chemical or surgical castration and androgen receptor inhibition. However, the disease usually progresses to castration-resistant prostate cancer (CRPC). A neuroendocrine pattern is frequently observed in the cellular composition of CRPC, which is considered to emerge as an effect of androgen deprivation therapy. This is the case report of a 69-year-old patient with prostate adenocarcinoma, who, after an initial period of disease control with radiotherapy and antiandrogens, was diagnosed with CRPC with high levels of prostate-specific antigen (PSA), unresponsive to androgen inhibition, with accompanying lung and osseous metastases. Bronchial biopsy of the lung metastasis revealed infiltration by non-small-cell adenocarcinoma of prostatic origin with neuroendocrine characteristics. On somatostatin receptor scintigraphy with 99m Tc-octreotide, there was high uptake by almost all known lung and osseous metastases. The patient was subsequently treated with a combination of docetaxel and octreotide, and a partial response was observed 6 months later, with reduction of the PSA level and the size of the lung metastasis. The aim of the present study was to provide a clinical example of the previously demonstrated, in vitro and in vivo, synergistic antitumor activities of docetaxel and octreotide in cases of CRPC selected by means of histological confirmation of their neuroendocrine nature and somatostatin receptor scintigraphy.

ACTH-secreting metastatic prostate cancer with neuroendocrine differentiation

“…These variable outcomes of docetaxel treatment can be clinically predicted by chromogranin A (CgA) response 21. Favourable response to docetaxel treatment in castration-resistant prostate cancer is associated with decreasing CgA, while rising CgA may be associated with poor prognosis 21. Nonetheless, CgA was not measured in our patient.…”

“…There is current evidence showing the effect of docetaxel in reducing tumour metastasis, on one hand, and increasing its resistance to treatment, contributing to metastasis, on the other hand 20. Although docetaxel has been shown to trigger neuroendocrine differentiation of prostate cancer, and thus treatment resistance and disease progression, it has also been shown to have a synergistic effect with octreotide in the treatment of castration-resistant prostate cancer with neuroendocrine differentiation and somatostatin receptor scintigraphy 16 21. These variable outcomes of docetaxel treatment can be clinically predicted by chromogranin A (CgA) response 21.…”

“…Although docetaxel has been shown to trigger neuroendocrine differentiation of prostate cancer, and thus treatment resistance and disease progression, it has also been shown to have a synergistic effect with octreotide in the treatment of castration-resistant prostate cancer with neuroendocrine differentiation and somatostatin receptor scintigraphy 16 21. These variable outcomes of docetaxel treatment can be clinically predicted by chromogranin A (CgA) response 21. Favourable response to docetaxel treatment in castration-resistant prostate cancer is associated with decreasing CgA, while rising CgA may be associated with poor prognosis 21.…”

Clinicopathological characteristics and survival outcomes in neuroendocrine prostate cancer

“…Most reports on NEPC are small sample size series or case reports. [ 14 – 17 ] Inadequate research has limited our ability to make definitive conclusions on clinical course, prognosis, and the most effective treatment. Thus, further studies are needed to increase our understanding of this important disease that may eventually help find novel therapies.…”