Malignancies associated with systemic sclerosis

Abstract

The outcome of systemic sclerosis (SSc) has become more favorable during the past years. Respiratory failure or renal crisis became less frequent, therefore more attention should be paid to long-term comorbidities, such as malignancies secondary to scleroderma. The incidence of malignant lymphoproliferative diseases, as well as that of solid tumors are higher in a number of rheumatic diseases including SSc. Some cytotoxic agents, primarily cyclophosphamide used in the treatment of SSc, as well as exposure to chemicals or smoking may further increase cancer risk. We also present malignancies in 218 scleroderma patients undergoing follow-up in our department were assessed for secondary malignancies. Although the number of SSc patients with tumor is relatively small, we compared our cohort to the Health for All Hungarian database and calculated standard incidence ratios (SIR). We identified 11 cases of malignancy in 10 SSc patients (4.6%). One patient had two types of tumor: breast cancer before the onset of SSc and later malignant lymphoma. Half of SSc patients with cancer belonged to the diffuse cutaneous (dcSSc) subtype. The mean age at onset of SSc was 54.6years, while that at the diagnosis of malignancy was 61.5years. The mean disease duration of scleroderma at the time of cancer diagnosis was 6.6years. Five patients died, 4 due to the underlying malignancy. Among the five surviving patients, the mean survival time was 4.9years. Altogether 3 patients had non-Hodgkin's lymphoma, 2 had bronchial cancer, 2 had breast cancer, one had leiomyosarcoma of the leg, one had esophageal cancer, one had cervix cancer and one had skin cancer. In comparison to the Health for All database, the overall SIR of all malignancies in SSc was 1.07 (CI: 0.82–1.38) varying between 5.8 and 52.4 in different tumor types. Only one cancer patient received cyclophosphamide therapy. In conclusion, secondary tumors including lung, skin and breast cancer, as well as lymphomas are more common in SSc than in the general population. The adequate treatment and follow-up of scleroderma patients may help us to lower the risk of malignancies secondary to SSc.