Mohs Micrographic Surgery as the Standard of Care for Nail Unit Squamous Cell Carcinoma

Abstract

BACKGROUND There is no established standard of care for treatment of nail unit squamous cell carcinoma (SCC). OBJECTIVE The aim of the study is to further characterize the clinical characteristics and diagnostic considerations of nail unit SCC and to examine the outcomes of patients with nail unit SCC treated with Mohs micrographic surgery (MMS). MATERIALS AND METHODS A retrospective review was conducted of patients treated for nail unit SCC with MMS from January 1, 2006, to December 30, 2016. Demographic data were collected along with lesion characteristics, treatment characteristics, and follow-up results. RESULTS Forty-two cases of nail unit SCC were treated with MMS. Recurrences were observed in 3 patients (7.1%). Recurrent cases were treated with MMS. There were no cases of distant metastases, subsequent recurrence, or death. Two of 3 recurrences occurred in patients with histologic features of verruca vulgaris. CONCLUSION Mohs micrographic surgery provides an excellent cure rate for the treatment of nail unit SCC. This technique offers the greatest ability to achieve histological clearance while maximizing tissue sparing, thereby reducing unnecessary amputations and patient morbidity.

Nail Unit Squamous Cell Carcinoma: Updates on Diagnosis, Surgical Approach, and the Use of Mohs Micrographic Surgery

“…These recurrent cases were then successfully treated with another round of MMS. 17 This study's cure rate was comparable to the cure rate of MMS for SCC in other cutaneous areas. Goldminz and Bennett 24 demonstrated a cure rate of 92% in their case series of 25 patients.…”

“…They reported a 78% cure rate with an average time to recurrence of 47 months. 23 In a series of 42 cases of NSCC treated with MMS, Gou et al 17 noted a cure rate close to 93%. In their study, recurrences were observed in only 3 patients (7.1%).…”

“…3,16 Unfortunately, there are no large case series to demonstrate the cure rate or effectiveness of these methods. 17 In one study, the authors did not recommend use of photodynamic therapy or topical modalities such as imiquimod cream 5% or fluorouracil cream 5% as first-line treatments of NSCC due to the difficulty in ensuring complete treatment of the sulci of the lateral and proximal nail folds. 18 More evidence in the literature supports surgical approaches, including wide local excision, MMS, and digital amputation.…”

Two discrete bands of longitudinal melanonychia on one fingernail

“…3 Although there are currently no standardized guidelines for treatment of nail unit SCC, the literature suggests MMS should be the primary method of treatment. 2 Our patient did not have evidence of bony invasion or metastatic disease and was treated with MMS of the nail bed and nail matrix with healing by secondary intention (Fig 3). Three months after surgery, there was no evidence of recurrence or complications.…”

“…It is a more aggressive approach to treatment and can be considered when MMS is not available. 2 MMS – Correct. Performing MMS on the nail unit can be difficult and time consuming but has been associated with high cure rates and maximum tissue sparing.…”