TY - JOUR T1 - Cancer-associated Dermatomyositis: Does the PD-1 Checkpoint Pathway Play a Role? JF - The Journal of Rheumatology JO - J Rheumatol SP - 731 LP - 732 DO - 10.3899/jrheum.180007 VL - 45 IS - 6 AU - MOISES LABRADOR-HORRILLO AU - ALBERT SELVA-O’CALLAGHAN Y1 - 2018/06/01 UR - http://www.jrheum.org/content/45/6/731.abstract N2 - Cancer-associated myositis represents a unique opportunity to study the complex relationship between cancer and autoimmunity. It is well recognized that dermatomyositis (DM) is the inflammatory myopathy most often associated with cancer. In clinical practice, nearly one-third of patients with DM present with associated malignant disease, and the remainder may harbor an occult cancer that could develop in the near future, or never appear1,2. The immune system likely has a role in determining which of these outcomes will ensue.Management of a patient with DM is difficult, because an occult malignancy may not always be detected by the available screening tools. One explanation for the uncertainty regarding the development of malignant disease in these patients is the concept of 3 sequential phases in the relationship between cancer and the immune system: elimination, equilibrium, and escape3. In this framework, patients with cancer-associated DM can be viewed in different ways. First, they can be seen as DM patients with concurrent malignant disease, which would indicate that elimination of the malignancy by the immune system has failed. Second, the patients could have an occult malignancy, but the immune system maintains a tight balance to prevent it from full development to cancer. This is the equilibrium phase, which can last for decades and helps explain the higher incidence of cancer in patients with DM even years after the … Address correspondence to Dr. M. Labrador-Horrillo, Vall d’Hebron General Hospital, Internal Medicine, Passeig Vall d’Hebron, 119-129 Barcelona, 08035 Spain. E-mail: mlabrador{at}vhebron.net. ER -