AB0334 Neoplasm risk in a rheumatoid arthritis cohort: a retrospective study
Authors: C. Ambrósio, A. Barcelos
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> It is well known that the risk of neoplasms is increased in rheumatic patients, especially in Rheumatoid Arthritis (RA), SLE and inflammatory myopathies. Although the relationship between neoplasms and some factors involving the pathophysiology and immunomodulatory therapy of this diseases is well known, we still don't know all the mechanisms underlying this process. Thereby, this theme has been of ongoing interest and research. <h3>Objectives</h3> To determine whether the incidence of neoplasm is increased in patients with RA compared to a matched comparison cohort and to identify risk for any individual malignancy in RA. <h3>Methods</h3> A cohort of 243 RA patients, who fulfilled 1987 ACR criteria for RA and a comparison cohort, sex and age matched without RA (non-RA) were evaluated retrospectively for cancer occurrence. Demographic, epidemiological, clinical, laboratorial and imaging data were collected through medical record review. All paraneoplasic cases were excluded. Descriptive statistics were used to summarise data of the RA and comparator group. <h3>Results</h3> 243 RA patients (mean age 62,9 y, 68,7% female, mean disease duration 10,6 y) were enrolled. 148 RA patients had rheumatoid factor (RF) present and 120 had anti-citrullinated peptide (anti-ccp) positive. Erosions were present in 106 RA patients. The prevalence of neoplasms was similar in RA and non-RA groups (n=24 <i>vs</i> 23, p=0,8) and 5 of the deads occurred in the RA-neoplasm group were due to the cancer. Of the 24 neoplasms in RA group, 9 appeared after the RA diagnosis was established (mean 10 years) and 17 before (mean 9,65 years). In RA patients correlation was found between male sex and neoplasm (p=0,04) as well as absence of RF rheumatoid factor and neoplasm (p=0,049). No correlation was found between the presence of neoplasm and anti ccp presence or erosions (p=0,3 and p=0,51 respectively). In this study, the overall risk of neoplasms in patients with RA was not associated with conventional or biological DMARD's. No differences were found between the type of tumour in RA patients <i>vs</i> non-RA, except for colon cancer, more prevalent in RA patients (p=0,03). Only 21 non-RA patients vs 19 RA patients were smokers and for so, it wasn't possible to establish any correlations. <h3>Conclusions</h3> In this study we found a prevalence of colon cancer in RA patients, as was found in other studies whoever, the increased risk for lung cancer and lymphoma often reported, was not found. It seems that male sex and the absence of rheumatoid factor are responsible for an increased risk. However we have several limitations: a very small sample, the population of the study was predominately Caucasian. Further studies examining specific aspects such as treatments, smoking or other lifestyle factors are needed to investigate the underlying mechanisms for the increased or decreased risk of specific cancers observed in patients with RA compared with the general population. <h3>References</h3> [1] Raheel S, Crowson CS, Wright K, Matteson EL. Risk of malignant neoplasm in patients with incident Rheumatoid Arthritis 1980–2007 in relation to a comparator cohort: a population based study. Int J Rheumatol2016;(8):1–6. [2] Simon TA, et al. Incidence of malignancy in adult patients with rheumatoid arthritis: a meta-analisis. Arthritis Res Ther2015;1(17):212. <h3>Disclosure of Interest</h3> None declared