Nail unit squamous cell carcinoma in people with immunosuppression

Nail unit squamous cell carcinoma (NUSCC) is uncommon and diagnosis is often initially incorrect or delayed. Immunosuppression appears important in the clinical behaviour of NUSCCs.

To highlight the frequency and nature of immunosuppression in a case series of patients with NUSCC, and identify the distinguishing characteristics in this subgroup.

Clinical, photographic and histological details were reviewed for all patients with NUSCC, over a 16-year period in a university dermatology department.

Forty-three patients were identified and seven (16%) were immunosuppressed. Patients with immunosuppression presented at a younger age (mean 52 vs. 63 years, P = 0.08) and sooner (mean 9 vs. 65 months, P < 0.001) than immunocompetent patients, and had a higher frequency of polydactylous disease [four of seven (57%) vs. two of 36 (6%), P < 0.001], relapse at the same site [two of seven (29%) vs. 0], and recurrent disease at other sites [four of seven (57%) vs. 0].

Immunosuppression plays a role in the development and clinical behaviour of NUSCCs. Clinicians should have a low threshold for early biopsy of nail dystrophies, particularly in those with immunosuppression. These patients are at higher risk of relapse and recurrent disease and therefore require prolonged follow-up.