Background Nail unit squamous cell carcinoma (nSCC) is a malignant subungual tumour. Although it has a low risk of metastasis and mortality, the tumour has a significant local recurrence rate. There is insufficient data to determine whether functional surgery is less effective than amputation for nSCC that does not involve the bone. Objectives We aimed to investigate existing data on the outcomes of functional surgery and amputation for nSCC without bone invasion. Materials and Methods We carried out an extensive search in PubMed, Embase, Cochrane Library, Web of Science, and Scopus for appropriate English-language academic papers, starting with the creation of individual resources until February 23, 2023. The main outcome was local recurrence. Initially, 2191 studies related to nSCC were selected. Information from every research study was retrieved and subdivided, comprising the year of publication, period, number of patients, age, gender distribution, tumour stage, type of intervention, number of recurrences, and follow-up period. Results Ten independent studies (319 lesions) were finally selected. Mohs micrographic surgery was the most reported surgical modality, followed by wide surgical excision and amputation. Local recurrence rates between Mohs micrographic surgery, wide surgical excision and amputation treatment were nearly identical. Other surgical methods included limited surgical excision, partial ablation, and limited excision until the clearing of margins, with recurrence rates up to 50%. Conclusions Given the functional impairment and psychological distress associated with phalanx amputation, functional surgery, including Mohs micrographic surgery and wide surgical excision , should be the preferred therapy for nSCC without bone involvement. Amputation should remain the preferred therapy for nSCC that involves the bone. Partial excision should be avoided. Further studies on whether Mohs micrographic surgery or wide surgical excision is a better option for nSCC not involving the bone are required.
Keywords: amputation; functional surgery; nail disease.; squamous cell carcinoma; systematic review.