Oral administration of vinorelbine can overcome intractable endovenous-vinorelbine-associated acute tumor pain

Vinorelbine (VNR, 5’-nor-anhydro-vinblastin)-associated acute tumor pain is a well-recognized complication of VNR administration in cancer patients. Although often responsive to NSAIDs and opioids, it can cause treatment discontinuation when intractable [1, 2, 3, 4]. Although the pathogenesis of this complication is unknown, the onset immediately after or during VNR administration suggests a relation between the symptoms and the peak of VNR blood concentration. Oral administration of VNR obtains a six-times-lower peak of blood concentration than intravenous administration, with a Cmax reached 1.5–3 h after drug intake [5]. According to this pharmacokinetic profile, we hypothesized that an oral administration of VNR could overcome VNR-associated pain symptoms. A shift from intravenous to oral VNR was done in two patients with non-small-cell lung cancer (NSCLC) who experienced VNR-related acute tumor pain despite prophylaxis with NSAIDs and opioids.