Background The pathogenetical association between autoimmunity and cancer has been previously described.
Objectives In this study we aimed to better describe the complex relationship between autoimmunity and neoplastic diseases in a retrospective cohort from our outpatient Immunorheumatology clinic. In particular we aimed to identify those immune conditions the diagnosis of which is associated to an increased risk of being diagnosed for a cancer within 2 years before and after the rheumatological syndrome onset.
Methods We evaluated 3975 clinical records from 1st January 2005 to 30th November 2012. We used non immune-mediated conditions (fibromyalgia and osteoarthritis) as controls. We included in the analysis only patients with at least 2 years of follow-up.
Results We reported 144/1750 cases of cancer in the general population (8.2% [6.91 – 9.49]), 41/702 of which (5.9% [4.16–7.64]) in control group. The prevalence of cancer was increased in patients affected by Sjogren's Syndrome (18.3% [8.52–28.08]; OR 3.62 [1.75–7.48]), Dermatomyositis/Polimyositis (42.9% [6.24–79.56]; 12.09 [2.65–55.8]), Vasculitis (18.8% [9.23–28.37]; 3.70 [1.81–7.52]) and Polimyalgia Rheumatica (24.0% [15.63–32.37]; 5.09 [2.92–8.88]). Logistic regression identified all these diagnosis, age >65 and male sex as independent risk factors for neoplastic disease.
Conclusions DM/PM, vasculitis and PMR show an increased risk of neoplasms during the whole observation period and a high prevalence of symptoms remission after cancer treatment as expected for a paraneoplastic manifestation; vice versa Sjogren's Syndrome seems to be more likely a causal factor for cancer (in particular lymphoma), since the risk is increased exclusively in the prospective follow-up and the treatment of cancer is not associated to a remission of rheumatological symptoms.
Disclosure of Interest None declared