The fact that itch may be associated with internal malignancy has previously been suspected. A recent study looked back at over 16,000 adult patient seen at the Johns Hopkins Health System from 2013-2017. They compared those with itch vs those without. Patients with pruritus (itch) were significantly more likely to have concomitant malignancy than those without pruritus. Most strongly associated were cancers of the liver, gallbladder and biliary tract, hematopoietic (blood) system, and skin. The study did not identify which came first, malignancy or itch, and did not identify the cause of the itch. Was it primarily the malignancy or the treatment or some other factor that cased the itching? None the less, the association has been confirmed such that patients with long term itching of no other apparent cause should be considered for a work up to rule out the most commonly associated malignancies..
Journal of the American Academy of Dermatology
Association Between Itch and Cancer in 16,925 Pruritus Patients: Experience at a Tertiary Care Center
J Am Acad Dermatol 2018 Sep 11;[EPub Ahead of Print], VA Larson, O Tang, S Stander, S Kang, SG Kwatra