Malignancy in systemic lupus erythematosus

Abstract

Objective. To estimate the risk of cancer in patients with systemic lupus erythematosus (SLE).Methods. Patients with SLE (n = 724) have been followed prospectively, for 24 years, at the University of Toronto Lupus Clinic. The diagnosis of cancer was confirmed by histologic or autopsy reports. Standardized rates of cancer and standardized incidence rates (SIR) (ratio of observed-to-expected cancers) were used to estimate the risk for cancers.Results. Twenty-four cancers were identified in 23 SLE patients (3.2%) during 7,233 patient-years of followup. Compared with the Ontario population, the overall estimated risk for all cancers was not increased in the lupus cohort (SIR 1.08, 95% confidence interval 0.70-1.62). A 4

Malignancy in Systemic Lupus Erythematosus

“…The earliest clinical evidence of an association of cancer with systemic lupus erythematosus came from case and case series reports (12)(13)(14)(15). Since then, cohort studies (16)(17)(18)(19)(20)(21)(22) have produced sorne evidence of increased cancer risk in systemic lupus erythematosus patients, although the conclusions have not been uniform (23)(24)(25).…”

“…Attempts to accurately estimate the cancer risk in systemic lupus erythematosus have most often been done with clinical cohorts (18)(19)(20)(21)(22)(23)(24)(25). In a clinical cohort, the subjects have a definite diagnosis of systemic lupus erythematosus, either by American College of Rheumatology criteria (26) or by clinicaljudgment (generaIly, this would mean a patient has definite signs oflupus, such as classic kidney involvement, but doesn't fit exact American College of Rheumatology criteria.…”

“…In a clinical cohort, the subjects have a definite diagnosis of systemic lupus erythematosus, either by American College of Rheumatology criteria (26) or by clinicaljudgment (generaIly, this would mean a patient has definite signs oflupus, such as classic kidney involvement, but doesn't fit exact American College of Rheumatology criteria. As systemic lupus erythematosus is a relatively rare condition (incidence has been estimated at 4.8 per 100,000 (1)) the size ofthese cohorts have been smaIl, (ranging from 116 (25) to 724 (24) confirmed by a sub-specialist. AIso, even if the diagnoses of systemic lupus erythematosus were accurate, a cohort assembled in this fashion would select for a particular group of systemic lupus erythematosus patients (those that had been admitted to hospital), not the entire population of systemic lupus erythematosus patients.…”

“…Thus, limitations in these clinical series and cohort studies have been small sample size (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25), inclusion of a cohort not representative of the general systemic lupus erythematosus population (16;17), reliance solely on either self-report or chart review (21)(22)(23)(24) without registry linkage, and absence of an appropriate age-adjusted population comparison group (13)(14)(15).…”

Role of radiation therapy in patients with a diagnosis of both systemic lupus erythematosus and cancer

“…SLE patients, by virtue of their disease, have basic defects in immune function that could be increased by the immunosuppressive therapy they receive. Several cohort studies showed an increase of non-Hodgkin's lymphoma (2,3) and of squamous cell skin cancer, especially in patients whose followup was longer than 15 years (4).…”