Photo Credit: Joyce Grace
Patients with lymphedema have twice the risk for skin cancer when compared with patients without lymphedema.
“For patients with nonmelanoma skin cancer, lymphedema is relatively common in lower extremities, and the fact that it has a risk factor for skin cancers warrants a need for screening in this patient population in order to control the lymphedema,” explains Afsaneh Alavi, MD. “To our knowledge, this is the first large-scale study evaluating the association between lower-extremity lymphedema and skin cancer, Dr. Alavi says. “Skin cancers are the most common cancer type, and it is important to recognize the risk factors, not only from a prevention perspective but also for identifying potential therapeutic targets.”
Based on the clinical observation, Dr. Alavi and colleagues identified multiple cases of skin cancer in patients with lower-extremity lymphedema and recognized the challenges in managing both lymphedema and skin cancer, along with the possible delay in diagnosis. They aimed to show whether lymphedema is a risk factor for skin cancer and whether surveillance is necessary.
Clinicians Need to Be Aware of the Association
“We identified 4,437 patients with lower-extremity lymphedema and compared them with a cohort of patients without lower-extremity lymphedema to quantify the incidence and duration of cancer and the type of cancer,” Dr. Alavi says. The study included all patients with the phrase “lower-extremity lymphedema” and with a diagnosis code for the condition in their EHR, plus age-, sex-, and race-matched controls without lymphedema. The researchers used the Kaplan-Meier curve to evaluate the time to develop the first skin cancer for the lymphedema cohort and controls. They used a Cox proportional hazards regression model to calculate HRs.
“We observed that the lymphedema group had a significantly increased risk for skin cancer (Table),” Dr. Alavi points out. “For the subset of patients with unilateral lymphedema, the lymphedematous extremity was 2.65 times as likely as the nonlymphedematous lower extremity to have skin cancer, particularly basal cell carcinoma (BCC). However, all studied forms of skin cancer, including BCC, squamous cell carcinoma, and angiosarcoma, were more common in the lymphedema group.” She adds that clinicians caring for patients with lower-extremity lymphedema should be aware of this increased risk and monitor at-risk patients accordingly.
Studies Needed to Understand Pathogenesis of Cancer in This Population
For future research, the study team hopes to raise awareness of the need for a high index of suspicion for skin cancer at anatomical sites with lymphedema. “It is important to educate clinicians who are dealing with patients with lymphedema or who are working in wound care clinics to be familiar with skin cancers and have access to immediate skin biopsy when needed,” she notes. “Patients with lymphedema have twice the risk for skin cancer than patients without lymphedema.”
Additionally, the study team concurs that future studies and investigations are needed to understand the pathogenesis of cancer in this population to help guide individualized management of skin cancer in patients with lymphedema. “This is particularly crucial to determine whether cancers on lymphedematous lower extremities are histologically and prognostically different from cancers on lower extremities that are not lymphedematous,” Dr. Alavi says.
