Systemic lupus erythematosus (SLE) patients have a higher risk for certain cancers — including cervical, thyroid, ovarian, and oral cancer, as well as lymphoma, multiple myeloma, and leukemia — than the general population, emphasizing the importance of cancer screening programs as part of SLE management.
The findings of the study, “Systemic lupus erythematosus is a risk factor for cancer: a nationwide population-based study in Korea,” were published in Lupus.
SLE, the most prevalent form of lupus, is a chronic autoimmune disease characterized by behavioral and psychological symptoms including pain, fatigue, depression, and impaired cognition. Previous studies have suggested that SLE patients are more likely to be affected by certain types of cancers, including non-Hodgkin’s lymphoma, lung, liver, and vaginal cancer.
“However, some studies have found a decreased risk of some hormone-sensitive cancers, such as breast, ovarian, and endometrial cancer, in SLE patients. However, whether patients with SLE have increased or decreased risk of breast cancer remains unclear,” the researchers said.
In this study, investigators set out to characterize the relationship between SLE and cancer in the entire Korean population.
The nationwide, retrospective, cohort study involved 21,016 SLE patients and 105,080 age- and sex-matched controls without SLE. The cohort was selected from the Korean National Health Insurance Service (NHIS) database between 2008 and 2014.
Over a follow-up period of seven years, 763 (3.36%) SLE patients and 2,667 (2.54%) controls developed cancer. The incidence risk of cancer was higher in SLE patients compared to controls (6.427 vs 4.466). Incidence risk refers to the chance of a disease happening over a defined period of time.
After accounting for age and sex, SLE patients showed a 44% higher risk of developing cancer. No differences in cancer risk were found between female and male SLE patients.
SLE patients at higher risk for cancer were younger (under 40) and male, being 12 and 29 times more likely of developing lymphoma than control subjects.
Looking at different cancer types, researchers found that SLE patients were more likely to develop cervical, thryoid, ovarian, and oral cancer, as well as lymphoma, leukemia, and multiple myeloma than controls.
On the other hand, no significant differences in the risk of stomach, colorectal, liver, pancreatic, lung, breast, prostate, biliary, laryngeal, renal, bladder, nerve, and skin cancer were found between SLE patients and controls.
While the mechanisms leading to increased risk of cancer in SLE patients are yet to be fully understood, the findings highlight the need for cancer screening programs among this patient population.
“In conclusion, SLE is an independent risk factor for malignancy, especially cervical, thyroid, ovarian, oral … as well as lymphoma, multiple myeloma, and leukemia. The importance of cancer screening programs should be emphasized in SLE patients,” the scientists concluded.