[Polyneuropathic pain therapy with a patient suffering from generalized castrate- resistant prostate cancer -  clinical case report].

BACKGROUND: Tapentadol is a µ -opioid receptors agonist as well as an inhibitor of noradrenaline reuptake. This pharmacologic profile of tapentadol makes it a suitable drug of choice in nociceptive and neuropathic pain control.

CASE REPORT: This clinical report pressents a 65year old man with poorly differentiated prostate cancer -  Gleason score 8 (4 + 4) with metastatic bone disease. Besides the initial application of bisphosphonates, the patient had been treated with androgen deprivation therapy (cyproterone acetate + leuprolide acetate) for the period of 18 months. This therapy was terminated due to an increase of PSA levels. Subsequently, the patient underwent palliative docetaxelbased chemotherapy. There were eight cycles applied with positive clinical and laboratory effect. However, the further application was limited by the averse effects, namely the peripheral neuropathy manifested by pain in arms and legs. The peripheral neuropathy had progressive tendency even after the end of chemotherapy, and supportive treatment with gabapentin and amitryptiline failed to succeed. Four months after zoledronic acid monotherapy, the patient was started on tapentadol in 50-mg dose b.i.d., consequently escalated to 100 mg b.i.d. (to this point, 25 µg of transdermal fentanyl were used for pain management). Significant relief from neuropathic discomfort was observed three weeks from the onset of tapentadol therapy. Patients state of health normalized within three months after the initiation of therapy. Consequently, the patient was able to receive docetaxel chemotherapy again, without any neuropathic pain exacerbation on the maintenance dose of tapentadol 50 mg b.i.d.

CONCLUSION: Tapentadol administration resulted in stable and longtime relief from neuropathic pain which is a frequent side effect in the course of castrate-resistant prostate cancer therapy with taxanes.