Simultaneous subungual melanoma in situ of both thumbs

Nail unit melanoma treated with Mohs micrographic surgery: Technique, local recurrence rate, and surgical outcomes

BACKGROUND

Nail unit melanoma (NUM) is increasingly treated with digit-sparing surgery, but few published case series describe Mohs micrographic surgery (MMS) for NUM.

OBJECTIVE

To describe the surgical technique, local recurrence rates, and reconstruction method for a large series of NUM treated with MMS using melanoma antigen recognized by T cells-1 immunostaining.

METHODS

Biopsy-proven NUM treated with MMS-melanoma antigen recognized by T cells-1 were identified from a prospectively maintained database (2008-2023). Primary outcome was local recurrence rate. Secondary outcomes included rate of subclinical spread and rate of ablative versus reconstructive amputation.

RESULTS

Sixty-nine NUM were identified, including 51 melanomas in situ (73.9%) and 18 invasive melanomas (26.1%) with mean Breslow thickness of 1.07 mm (range 0.2-5.4 mm). One local recurrence (1/69, 1.4%) occurred during a mean follow-up time of 38.2 months. Subclinical spread (>1 Mohs stage) was common (38/69, 55.1%). Amputation was rarely necessary to clear the melanoma (5/69, 7.2%), but amputation at different levels was performed to reconstruct 33 cases (33/69, 47.8%) with extensive exposed bone.

LIMITATIONS

Single center cohort and lack of patient-reported outcomes.

CONCLUSION

MMS treats NUM with low local recurrence rates. Amputation is rarely necessary to obtain clear tumor margins, but it may be necessary or desirable to reconstruct MMS defects with extensive exposed bone.

Mohs Micrographic Surgery Is Equivalent to Nail Unit Excision or Amputation for Melanoma In Situ of the Nail Unit: A Systematic Review and Meta-Analysis

BACKGROUND

Local recurrence (LR) rates of melanoma in situ (MIS) of the nail apparatus treated with different surgical modalities are unknown.

OBJECTIVE

To evaluate the differences in LR rates of nail apparatus MIS treated with Mohs micrographic surgery (MMS) versus nail unit excision (NUE) versus amputation.

METHODS

Studies of nail/subungual MIS treated with MMS, NUE, or amputation were identified through multiple literature databases, including PubMed, MEDLINE, Embase, Web of Science, and Cochrane Library. Pooled data were assessed through meta-analyses and Fisher exact test.

RESULTS

Of 280 studies identified, 20 met inclusion criteria (7 comparative studies and 13 single-arm studies). Among the 7 comparative studies, the LR was 4.38% (5/114) after NUE and 2.94% (1/34) after amputation (odds ratio: 0.937; 95% CI: 0.237-3.703). In the 13 noncomparative studies, 23 patients underwent MMS (pooled LR estimate: 11.07%; 95% CI: 3.22%-31.81%) and 140 patients underwent NUE (pooled LR estimate:8.04%, 95% CI: 4.43%-14.16%). The difference in LR rate between MMS, NUE, and amputation was not statistically significant ( p = .578).

CONCLUSION

Local recurrence of nail/subungual MIS in cases treated with MMS was not statistically different than in cases treated with NUE and was comparable to amputation. Further studies investigating the use of MMS for the treatment of nail/subungual MIS are warranted.

Blue Nail Discoloration: Literature Review and Diagnostic Algorithms

Blue nail discoloration is a distinctive clinical presentation, and diagnosis is challenging given the broad differential diagnosis. A comprehensive review of the literature describing blue discoloration of one or multiple nails was performed using the PubMed, Embase, Scopus, and Web of Science databases. A total of 245 publications were included and grouped based on involvement of a single nail (monodactylic) or multiple nails (polydactylic). Monodactylic blue discoloration was associated with tumors or benign nevi, most commonly glomus tumors, followed by blue nevi and less commonly melanomas. Polydactylic blue discoloration was frequently associated with medications (such as minocycline, zidovudine, and hydroxyurea), toxic and exogenous exposures (such as silver), and other medical conditions (such as HIV/AIDS and systemic lupus erythematous). Patients presenting with blue nail discoloration warrant a thorough history, physical examination, and workup to rule out malignancy, systemic disease, or toxic exposure. We present diagnostic algorithms for monodactylic and polydactylic blue nail discoloration to guide workup and treatment plans.

Mohs micrographic surgery for nail unit tumours: an update and a critical review of the literature

Mohs micrographic surgery (MMS) is a good treatment option for epithelial neoplasms, especially when localized in areas where tissue conservation is crucial, such as the nail unit (NU). MMS is a method of radical excision offering high cure rates due to the margin control and functional preservation. Our aim is to provide a review on the use of MMS for the treatment of the most common nail tumours. We revised the current literature on the use of MMS to treat malignant neoplasms (Bowen's disease, squamous cell carcinoma, melanoma, basal cell carcinoma, keratoacanthoma, carcinoma cuniculatum) and benign neoplasms (onychomatricoma and glomus tumour). MMS represents a successful surgical option for nail tumours, firstly in terms of tissue conservation: the NU anatomy is complex and the preservation of the component structures is imperative for its functionality. Secondly, due to the surgical radicality, which is essential not only for the clearing of malignant tumours, but also for benign cases, in order to reduce recurrences. Although a conservative treatment of NU melanoma with MMS has been proposed, in our experience, the conservative approach with functional surgery is a good option for the treatment of non-invasive melanoma (in situ and Ia).

Tips for diagnosis and treatment of nail pigmentation with practical algorithm

The observation of a black-brown pigmentation of the nail is often alarming for the patient and for the clinician, as they are aware that it can be a possible clinical manifestation of melanoma of the nail apparatus. Luckily, however, nail melanoma is a much less frequent cause of brown-black nail color than other melanocytic and nonmelanocytic pigmentations, which include subungual hematoma, exogenous pigmentations, and melanonychia due to benign conditions. A correct clinical history and careful examination help the clinician to distinguish the different conditions and to decide the correct management of melanonychia both in children and in adults.