Please login or create an account. If you do not have access to this content, you will be shown a 30 second preview and licensing options.
- Presentation
Diagnosis and Treatment of Nail Unit Squamous Cell Carcinoma
Description
The talk reviewed state-of-the-art diagnosis and treatment of nail unit squamous cell carcinoma, emphasizing that it can mimic many benign nail disorders, including warts, chronic paronychia, onycholysis, and longitudinal melanonychia or erythronychia, so clinicians should maintain a high index of suspicion and biopsy recalcitrant lesions. Risk factors include high-risk HPV, smoking, chronic trauma, occupational exposures, and immunosuppression, with HPV implicated in many cases and surveillance remaining important. Diagnosis is best made with full-thickness sampling, often using a nail wedge biopsy or avulsion-assisted biopsy that reaches bone when needed; nail clipping findings such as atypical parakeratosis may support suspicion but do not replace biopsy. Imaging is not routinely recommended for all patients because it can yield false positives or negatives and should be used selectively. For treatment, complete surgical excision with clear margins is the cornerstone, with Mohs surgery considered the gold standard when available and wide or en bloc excision effective when not. Recurrence rates after surgery are generally low, even in larger series, though immunosuppressed patients may recur more often. If bone is involved, careful bony margin management with tools like bone cutters may avoid unnecessary amputation. Key takeaways were: biopsy suspicious nail lesions early, obtain full-thickness specimens, and prioritize margin-controlled surgical treatment.
View moreConclusions
- Nail unit squamous cell carcinoma has highly variable clinical appearances, so persistent or unusual nail lesions should be approached with a low threshold for biopsy.
- High-risk HPV appears to be a major associated factor in many cases of nail unit squamous cell carcinoma, and patients may need long-term surveillance for recurrence and other HPV-related disease.
- Full-thickness sampling is essential for diagnosis because superficial biopsies can miss invasive disease and produce false-negative results.
- Nail wedge biopsy or similarly deep, well-mapped excisional sampling is the preferred diagnostic approach when nail unit SCC is suspected.
- Routine imaging is not supported for every patient with suspected or confirmed nail unit squamous cell carcinoma and should be reserved for selected cases.
- Complete surgical excision is the mainstay of treatment and is associated with lower recurrence than non-surgical therapies.
- Mohs micrographic surgery is presented as the gold standard when available because it offers excellent cure rates and low recurrence.
- If Mohs surgery is not available, en bloc or wide local excision can still be curative when clear margins are achieved.
- Amputation is generally reserved for cases with confirmed bony invasion at the deep margin, but careful bone-margin techniques may sometimes avoid it.
- Maintaining the nail plate during Mohs and carefully managing nail-fold anatomy can improve specimen quality and margin interpretation.
- Overall, the key message is to suspect early, biopsy deeply, confirm clear margins, and favor surgery for definitive management.
- J Am Acad Dermatol. 2019 Dec;81(6):1358-1370.
- Skin Appendage Disord 2024;10:199-206.
- Dermatologic Surgery 46(11): p 1375-1381, November 2020.
- Starace M, et al. Dermatol Pract Concept. 2018;8(3):238-244.
- Lambertini, et al. JEADV 2018, 32, 1638-1644.
- Shimizu A, et al. J Am Acad Dermatol 2019;81:1358-70.
- Dika E., et al. Dermatol Surg 2019;45:365-370.
- Dijksterhuis A, et al. J Hand Surg Am. 2018;43(4):374e379.
- Dermatologic Surgery 48(3):p 267-273, March 2022.
- Texas Dermatol Surg 2020;46:725-732
- Penn J Am Acad Dermatol. 2024 Apr;90(4):832-833.
- JAMA Dermatol. 2017;153(5):442-448