Cancer incidence in Familial Mediterranean Fever: A retrospective analysis

Familial Mediterranean Fever (FMF) is the most common hereditary monogenic fever syndrome that is characterized by recurrent attacks of fever and polyserositis. Anti-inflammatory drugs, with colchicine being the first-line therapy, have been used in the management of FMF. This study aims to evaluate the risk of cancer in Turkish FMF patients.

We retrospectively screened the cancer-related outcomes of our study group which consisted of Turkish FMF patients registered at our division. Cancer estimates of the Turkish population were published by the Turkish Ministry of Health in the Turkey Cancer Statistics Report 2018. Standardized incidence rates (SIR) were calculated to compare the cancer incidence observed in our study group with the expected cancer incidence of the Turkish population. Subgroup analyses were conducted on the subgroups, based on gender and usage of biological agents.

Our study included 1734 FMF patients, 1054 (60.8 %) of whom were females. The total follow-up was 68,784 person-years. Cancer was observed in 35 (2 %) of these patients. Turkish FMF patients had a significantly lower incidence of cancer, compared with the overall Turkish population [SIR 0.64 (95 % CI 0.46-0.89), p < 0.01]. No significant association was found between cancer and biological agent therapies in FMF patients.

Findings from our study indicate that the risk of cancer was decreased by 36 % in Turkish patients with FMF, compared with the outcomes of the overall Turkish population. Life-long exposure to anti-inflammatory drugs, primarily colchicine, may be the underlying reason for this outcome. Further studies are needed for the confirmation and explanation of this association.