Development of castration resistance in prostate cancer patients treated with luteinizing hormone-releasing hormone analogues (LHRHa): results of the ANARESISTANCE study.

PURPOSE: Evaluate the percentage of patients with prostate cancer treated with luteinizing hormone-releasing hormone analogues (LHRHa) that develop castration resistance after a follow-up period of 3 years. The secondary objective is to evaluate the variables potentially related to the progression to castration resistant prostate cancer (CRPC). METHODS: A post-authorization, nation-wide, multicenter, prospective, observational, and longitudinal study that included 416 patients treated with LHRHa between 2012 and 2017 is presented. Patients were followed for 3 years or until development of CRPC, thus completing a per-protocol population of 350 patients. A Cox regression analysis was carried out to evaluate factors involved in progression to CRPC. RESULTS: After 3 years of treatment with LHRHa 18.2% of patients developed CRPC. In contrast, in the subgroup analysis, 39.6% of the metastatic patients developed CRPC, compared with 8.8% of the non-metastatic patients. The patients with the highest risk of developing CRPC were those with a nadir prostate-specific antigen (PSA) > 2 ng/ml (HR 21.6; 95% CI 11.7-39.8; p < 0.001) and those receiving concomitant medication, most commonly bicalutamide (HR 1.8; 95% CI 1-3.1, p = 0.0431). CONCLUSIONS: The proportion of metastatic patients developing CRPC after 3 years of treatment with LHRHa is consistent with what has been previously described in the literature. In addition, this study provides new findings on CRPC in non-metastatic patients. Concomitant medication and nadir PSA are statistically significant predictive factors for the time to diagnosis of CRPC, the nadir PSA being the strongest predictor.

First evidence of oncologic neuropathic pain prevalence after screening 8615 cancer patients. Results of the On study.

BACKGROUND: Thirty percent to ninety percent of cancer patients suffer from pain, including neuropathic pain (NP), which results in great burden for cancer patients. Thus, it was of great interest to determine NP prevalence in cancer patients in Spain, to raise awareness of the condition, and aiming to improve management of cancer NP. PATIENTS AND METHODS: A 1-month follow-up prospective epidemiological multicenter study was conducted to assess prevalence and management of NP in Spanish oncologic units. The first 10 cancer patients at each unit diagnosed with NP by the validated Douleur Neuropathique 4 questionnaire (DN4) were recruited. RESULTS: Of 8615 screened patients, 2567 (30%) suffered from pain. From these, 33% had NP according to investigators and 19% according to DN4 test. Three hundred and sixty-six patients (mean age 62.6 years; 61.2% male) were recruited. Pain decrease at 1 month was greater in patients with metastases (P<0.01) and depended on treatment (P<0.05), with 'oxycodone' showing 50.4% pain relief. CONCLUSIONS: NP prevalence in cancer pain is 33%. DN4 reports only about half the cancer NP cases diagnosed by clinicians. Pharmaceutical treatment of cancer pain, including NP, has a greater effect in patients with metastases and seems to depend on the specific treatment used.