A 68-year-old farmer from rural Maharashtra presents with a non-healing ulcer on the dorsum of his left hand for 8 months. He reports the lesion started as a small nodule that gradually enlarged and ulcerated. On examination, there is a 2.5 cm indurated, hyperkeratotic ulcer with raised, everted edges and a granulating base. There is regional lymphadenopathy. Dermoscopy shows atypical vessels and a hyperkeratotic surface. A skin biopsy reveals well-differentiated squamous cell carcinoma with invasion into the dermis. What is the most appropriate next step in management?

Explanation

## Clinical Presentation & Diagnosis This patient has a well-differentiated squamous cell carcinoma (SCC) of the skin with several high-risk features: **Key Point:** The presence of regional lymphadenopathy indicates potential nodal involvement, which mandates comprehensive staging and assessment. **High-Yield:** Risk factors for aggressive SCC include: - Size > 2 cm (this lesion is 2.5 cm) - Depth of invasion (dermal invasion present) - Poor differentiation (though this is well-differentiated, nodal involvement elevates risk) - Location on dorsal hand (sun-exposed, high-risk site) - Regional lymphadenopathy (stage III disease) ## Management Algorithm ```mermaid flowchart TD A[SCC with dermal invasion + lymphadenopathy]:::outcome --> B{Risk stratification}:::decision B -->|High-risk features present| C[Wide local excision 4-6 mm margins]:::action C --> D[Lymph node assessment]:::action D --> E{Nodal involvement?}:::decision E -->|Yes| F[Sentinel lymph node biopsy or regional dissection]:::action E -->|No| G[Follow-up surveillance]:::action B -->|Low-risk| H[Excision or Mohs]:::action ``` **Clinical Pearl:** The presence of palpable regional lymphadenopathy in SCC mandates formal nodal assessment—this is not optional. Sentinel lymph node biopsy (SLNB) or therapeutic lymph node dissection may be indicated depending on nodal involvement. **Key Point:** Wide local excision with adequate margins (4–6 mm for low-risk, up to 10 mm for high-risk lesions) is the gold standard for invasive SCC. Mohs micrographic surgery is reserved for specific anatomical sites (face, ears, lips) where tissue preservation is critical, but it does NOT replace nodal assessment. ## Why Option 1 (Topical 5-FU) Is Incorrect Topical 5-FU is suitable only for actinic keratosis and superficial SCC (Tis, T1a). This patient has invasive dermal SCC with nodal involvement—topical therapy is inadequate. ## Why Option 3 (Mohs Alone) Is Incorrect Mohs micrographic surgery provides excellent margin control but does NOT assess regional lymph nodes. With palpable adenopathy, nodal staging is mandatory and cannot be omitted. ## Why Option 4 (Interferon-Alpha) Is Incorrect Intralesional interferon is an adjunctive or palliative measure, not primary treatment for invasive SCC with nodal disease. It has no role in early-stage management. [cite:Robbins 10e Ch 25]