TOPLINE:

A nationwide Swedish register-based study revealed that individuals with systemic sclerosis had a higher risk for hematologic malignancies. Myeloid malignancies typically presented around disease onset, whereas lymphoid malignancies appeared years later, and the risk was highest among men and patients aged 18-49 years at diagnosis.

METHODOLOGY:

• Researchers conducted a nationwide cohort study (2004-2020) using data from Swedish administrative healthcare registers to compare the risk for hematologic malignancies between patients with systemic sclerosis and those without.
• Incident systemic sclerosis was defined as two outpatient visits or hospitalizations with a main diagnosis code; 1720 patients with incident systemic sclerosis and 16,983 matched comparators from the general population were observed for 11,480 and 131,021 person-years, respectively.
• The mean age in the cohorts was 58.7-58.8 years, and majority of participants (81%) were women.
• Participants were stratified by sex and age at diagnosis, and patterns of incidence of hematologic malignancies were explored over time since the diagnosis of systemic sclerosis.
• All hematologic malignancies were identified using the Swedish Cancer Register.

TAKEAWAY:

• Compared with individuals without systemic sclerosis, those with the condition had more than double the risk for hematologic malignancies (hazard ratio [HR], 2.2; 95% CI, 1.4-3.1), with B-cell malignancies showing the strongest association (HR, 3.0; 95% CI, 1.7-4.8).
• Men with systemic sclerosis had a higher risk for hematologic malignancies (HR, 3.1; 95% CI, 1.4-5.7) than women (HR, 1.9; 95% CI, 1.2-2.9).
• The association was most pronounced in individuals aged 18-49 years at diagnosis (HR, 7.7; 95% CI, 3.5-14.3).
• Most hematologic malignancies were diagnosed a few years after the diagnosis of systemic sclerosis, with a median time to diagnosis of 2.6 years; myeloid malignancies presented close to the diagnosis of systemic sclerosis (median time, 0.1 years), whereas lymphoid malignancies appeared later (median time, 3.1 years).

IN PRACTICE:

“This study provides valuable insights for clinicians monitoring patients with SSc [systemic sclerosis] at risk of hematological malignancies and may aid in developing targeted cancer screening algorithms. Despite the increased risk, the absolute risk remains low, emphasizing the need for selective screening and reassuring patients about their individual risk levels,” the authors wrote.

SOURCE:

The study was led by Karin Gunnarsson, MD, Karolinska Institutet, Stockholm, Sweden. It was published online on November 11, 2025, in RMD Open.

LIMITATIONS:

The study lacked information on some possible confounders such as immunodeficiencies or genetic factors, leading to residual confounding. Information on clinically relevant features such as serologic profile and systemic sclerosis subtype, which are known to correlate with cancer risk, was absent. The study did not analyze or adjust for use of immunosuppressive medications, which may have influenced the risk for hematologic malignancies.

DISCLOSURES:

The study received funding from the Swedish Research Council, Swedish Cancer Society, and Swedish Rheumatism Association. Some authors disclosed receiving speaker honoraria from, serving on advisory boards of, and engaging in ongoing discussions about potential research collaborations or having other ties with various pharmaceutical companies; all relationships are unrelated to the present study.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.