To examine pain in cancer patients referred for specialized palliative care, we described pain characteristics and medication on admission, examined changes in pain during the first week, and searched for predictors of initial pain intensity and treatment outcome. On arrival in the department (T0) and after one week (T1), pain was evaluated with the Edmonton Symptom Assessment System (ESAS) and EORTC QLQ-C30. Analgesics were recorded. We investigated the associations between initial pain scores as well as differences from T0 to T1, and clinical and sociodemographic parameters, initial medication, and medical interventions. Of 267 eligible patients, initial pain scores were obtained from 175. Initial pain scores were high, although 81% of patients received opioid treatment at T0. Bone metastases, neuropathic pain, mixed pain pathophysiology, and breakthrough pain were associated with higher initial pain scores. Pain scores decreased during the first week. No single parameter convincingly predicted a better or worse outcome of pain treatment.