Functional surgery may reduce recurrence risk in nail unit melanoma

Functional surgery may be an attractive option in patients with nail unit melanoma who have a Breslow thickness less than 0.8 mm, according to a study.

“Functional surgery, rather than amputation, is a treatment option for minimally invasive nail unit melanoma, but its indication requires clarification,” Byung Ho Oh, MD, PhD, of the department of dermatology and cutaneous biology research institute at Yonsei University College of Medicine, Seoul, South Korea, and colleagues wrote.

In the retrospective review of 140 patients with nail unit melanoma, Oh and colleagues assessed optimal cutoff points of Breslow thickness for stratifying recurrence risk. The analysis included 33 patients who underwent amputation and 107 who underwent functional surgery at a tertiary referral center between 2008 and 2022.

Mean Breslow thickness values were 3.14 mm ± 2.62 mm in the amputation group and 0.7 mm ± 1.36 mm in the functional surgery group.

Patients who underwent amputation were followed for a mean duration of 3.97 ± 3.19 years, whereas those in the functional surgery group were followed for 3.8 ± 2.62 years.

The recurrence rate in the amputation arm was 30.3%, whereas 21.5% of those in the functional surgery arm experienced this outcome. The 5-year recurrence-free survival rates were 57.9% (95% CI, 40.2%-83.4%) for amputation and 74.8% (95% CI, 65.5%-85.4%) for functional surgery, according to the findings.

The rates of distant disease were 30.3% for amputation and 7.48% for functional surgery. Five-year distant-disease-free survival rates were 57.9% (95% CI, 40.2%-83.4%) in the amputation group and 88.8% (95% CI, 81.6%-96.7%) in the functional surgery group.

A number of factors demonstrated associations with recurrence or distant disease, including male sex, greater Breslow thickness, amelanotic color, ulcers and nodules.

The optimal cutoff for stratification of recurrence risk after surgery was determined to be a Breslow thickness of 0.8 mm (OR = 5.32; 95% CI, 2.04-13.85).

The applicability of the findings is limited by the small sample size.

“Functional surgery is suggested for nail unit melanoma without amelanotic color, nodules and ulcers,” the researchers wrote. “However, nail unit melanoma with [at least] 0.8 mm invasion depth shows greater recurrence risk after functional surgery.”