When compared to general population, patients with rheumatoid arthritis are at higher risk of some malignancies (especially lymphomas and lung cancer). Genetic predisposition, chronic inflammatory stimuli and viral infections are some of the reasons untreated patients are at higher risk. Clinical studies and national/international registries collect the data about the malignancies with higher incidence (such as lung, skin and breast cancer) but on the other hand, malignancies with lower incidence (such as sarcomas) are rarely reported. We report a case of a 47-year-old male with a history of a malignant intracranial chondrosarcoma/osteochondroma who developed seropositive rheumatoid arthritis. Due to progression of erosions, the patient was initialy treated with conventional synthetic Disease-Modifying Antirheumatic Drugs (csDMARDs) and later on with rituximab. The patient's rheumatoid arthritis went and remained in remission on maintenance therapy with rituximab (every 6-8 months) and low-dose methotrexate with no relapse of malignant intracranial chondrosarcoma/osteochondroma. Rituximab should be considered as a treatment option in patients with rare and agressive malignancies, such as sarcomas.
Keywords: Case-based review; Chondrosarcoma; Malignancy; Rheumatoid arthritis; Rituximab.