COPENHAGEN – Patients with venous leg ulcers have an increased risk of occult cancer – especially hematologic and immune-related malignancies, according to a Danish nationwide cohort study.
The risk of newly detected cancer was greatest during the first 89 days after diagnosis of a venous leg ulcer. Indeed, during that initial period the risk of being diagnosed with a hematologic cancer was 3.48-fold greater than expected based upon Danish Cancer Registry data, Dr. Sigrun Alba Johannesdottir Schmidt reported at the annual congress of the European Academy of Dermatology and Venereology.
It’s reasonable to assume that the vast majority of cancers identified within a year following diagnosis of a venous leg ulcer were probably present at the time when the ulcer was first diagnosed, meaning venous leg ulcers can serve as a red flag for occult cancer.
However, it’s also worth noting that the increased risk of hematologic malignancies persisted, albeit to a lesser degree, for up to 10 years. This suggests that venous ulceration could also have a carcinogenic effect. It’s biologically plausible that a venous leg ulcer could promote development of cancer through a variety of mechanisms, including inflammation, alteration of plasma viscosity and the adhesive properties of blood cells, and disruptions of venous pressure that encourage direct neoplastic invasion, according to Dr. Schmidt of Aarhus (Denmark) University.
She presented a Danish national patient registry study, which included all 29,705 patients with a first-time inpatient, outpatient, or emergency department diagnosis of a venous leg ulcer during 1982-2010. Fifty-five percent of them were age 70 years or older at the time of ulcer diagnosis. And 42% had moderate to very severe comorbid conditions based upon their Charlson Comorbidity Index score. During a median of 5.1 years of follow-up, or a total of 203,453 person-years, their overall risk of a first-time cancer diagnosis was significantly increased by 11%,compared with the general Danish population.
The malignancy risk was strongly time-dependent . However, the absolute risk of cancer was relatively low: less than 1% within the first 90 days after diagnosis of a venous leg ulcer. The number of patients who would need to be examined for a possible malignancy at the time of diagnosis of a venous leg ulcer in order to diagnosis one excess cancer was 146.
Dr. Schmidt indicated she would defer to experts in cost-benefit analysis as to whether an extensive work-up for occult malignancy is worthwhile in patients with a newly diagnosed venous leg ulcer, given the low absolute risk of cancer.
She reported having no financial conflicts of interest regarding her study, which was conducted with Danish institutional research funds.