Squamous Cell Carcinoma in Situ of the Nail Unit: Current Evidence and Recommendations for Patient Centered Treatment.

Squamous cell carcinoma in situ of the hand and nail is an infrequent tumor but represents the majority of hand and nail malignancies. While the conventional treatments of invasive nail unit squamous cell carcinoma include Mohs micrographic surgery, wide local excision, or distal digit amputation, no standardized management paradigm for in situ disease exists and the necessity of surgical options is debated. This review aims to discuss the most commonly reported treatment methods and critically assess relevant management considerations in order to facilitate appropriate treatment decisions for nail unit SCCis across dermatologic practice settings. Assessment of the current literature reveals insufficient evidence to determine a standardized treatment for nail unit squamous cell carcinoma in situ. Rather, management is greatly impacted by multiple factors including the presence of subungual involvement, surgical candidacy, importance of curative treatment, and patient preferences regarding cosmesis and function versus cure. When cure is desired, Mohs micrographic surgery is the treatment of choice in most cases. In the setting of desired curative intent, but poor surgical candidacy, radiotherapy may be effective and provide a reasonable chance of functional and cosmetic preservation. Other methods including photodynamic therapy, electrodesiccation and curettage, cryotherapy, and intralesional chemotherapeutics may be appropriate in specific circumstances, but are generally limited by lack of evidence or impracticalities. Lastly, observation with palliation may be appropriate when considering exceedingly rare disease-related mortality.

Management of a Unique Presentation of a Common Dermatologic Condition.

CONTEXT: Skin rashes are a common complaint seen in the primary care setting. There are many dermatologic conditions which a primary care provider (PCP) should be able to recognize and manage. One such condition is granuloma annulare (GA), which commonly presents as smooth, annular plaques on the trunk and/or extremities. Rashes like GA rarely present as unique variants and may be difficult for PCPs to determine from patient history and physical exam alone. Patch granuloma annulare (patch GA) is an example that may clinically mimic a cutaneous lymphoma known as mycosis fungoides (MF). PCPs should ideally be able to recognize the utility of performing a skin biopsy and/or referring the patient to a dermatologist when history and physical exam alone are insufficient. The histologic findings of skin biopsies often become essential in establishing a proper diagnosis and guiding patient management in unique dermatologic variants. EXAMPLE CASE: The patient in this clinical practice report is a Caucasian female in her late 60s who presented to a dermatology clinic with a two-year history of a worsening widespread eruption on her trunk and extremities. She had been evaluated previously by her PCP about 4 months prior and, without obtaining skin biopsies, treated her with a medium potency topical corticosteroid cream. The eruption had spread over her hips, buttocks, back, thighs, wrists, and elbows. Multiple skin biopsies of affected sites were taken by the second author and revealed findings consistent with patch GA. The patient was started on topical betamethasone dipropionate 0.05% ointment twice daily and noted marked improvement of her symptoms. CONCLUSIONS: Although GA is a benign condition of the skin that may be readily detected by PCPs, skin biopsies may be necessary to establish a proper diagnosis when this condition presents as a unique variant (e.g., patch GA). Therapy for patch GA often begins with a trial of high-potency topical steroid therapy in combination with ultraviolet light exposure, depending on disease severity and patient preference. Early evaluation with a skin biopsy by her PCP or an earlier referral to a dermatologist to have skin biopsies performed likely would have helped establish a prompter diagnosis and treatment plan for this patient.

Impact of Biopsy Technique on Clinically Important Outcomes for Cutaneous Melanoma: A Systematic Review and Meta-analysis.

We performed a systematic review and meta-analysis to examine the relationship between the type of biopsy technique employed in the diagnosis of cutaneous melanoma and 4 clinically important outcomes: melanoma-specific mortality, all-cause mortality, Breslow tumor depth, or melanoma recurrence. Our database was obtained by searching PubMed, Ovid MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews, and the Cochrane Library from inception until December 6, 2019. Studies were identified that compared biopsy techniques used to diagnose cutaneous melanoma with any of our study outcomes. We included 7 observational studies for our meta-analysis after screening 3231 titles and abstracts. Pooled data identified a significantly higher all-cause mortality in the punch biopsy group (risk ratio [RR], 1.520; P=.02). A higher, but nonsignificant, rate of melanoma-specific mortality (RR, 1.96; P=.22) and melanoma recurrence (RR, 1.20; P=.186) was also found for the punch biopsy group. Breslow tumor thickness was not significantly lower for punch incision (standardized mean difference, -0.42; P=.27). We found limited evidence for differences in clinically important outcomes across the spectrum of the most common methods employed in clinical practice for the initial diagnosis of cutaneous melanoma. A small, but significant, increase (P=.02) in all-cause mortality with punch biopsies was not seen for the other outcomes and was most likely due to small sample sizes and demographic differences in the included studies and unlikely represents a clinically important outcome. Our findings support the use of existing clinical practice guidelines for evaluating pigmented lesions suspicious for cutaneous melanoma.