A 62-year-old man from Delhi presents with a 1.5 cm pearly nodule with central ulceration and rolled edges on the right cheek. Dermoscopy shows arborizing vessels. He has no systemic symptoms or evidence of metastatic disease on examination. What is the most appropriate next step in management?

## Clinical Diagnosis The clinical presentation is classic for **basal cell carcinoma (BCC)**: pearly nodule with central ulceration (rodent ulcer), rolled edges, and dermoscopic arborizing vessels on the cheek — a sun-exposed, cosmetically sensitive facial site. ## Why Mohs Micrographic Surgery is the Best Next Step **Key Point:** The cheek is considered a **high-risk anatomical zone** for BCC (along with the nose, eyelids, lips, ears, and temples). For facial BCCs — even those <2 cm — Mohs micrographic surgery (MMS) is the **gold standard** per NCCN and BAD guidelines because: 1. **100% margin assessment** — Mohs examines the entire peripheral and deep margin (vs. ~1% sampled in standard excision), giving the highest cure rate (~99% for primary BCC) 2. **Tissue-sparing** — critical on the face for cosmesis and function 3. **Definitive treatment in a single procedure** — combines excision + histopathology simultaneously 4. **Facial location = high-risk zone** — recurrence on the face carries significant morbidity; MMS minimises this risk **High-Yield:** NCCN guidelines classify BCC on the face (excluding low-risk zones) as **high-risk**, for which MMS is the preferred treatment regardless of size. ## Why Not Other Options? | Option | Reason Not Preferred | |---|---| | **Wide local excision with 5 mm margins under GA** | Unnecessarily aggressive (GA adds morbidity); does not offer 100% margin control; inferior cure rate vs. Mohs on the face | | **Topical imiquimod 5%** | Suitable only for small (<2 cm) **superficial** BCCs; contraindicated for nodular BCC with ulceration; not appropriate for facial high-risk lesions | | **Excisional biopsy with 3 mm margins + histopathology** | A two-step approach (biopsy then re-excision) is suboptimal; 3 mm margins on the face are inadequate for nodular BCC and do not guarantee complete excision; Mohs achieves diagnosis and treatment simultaneously | ## Risk Stratification Summary | Feature | This Patient | Risk Level | |---|---|---| | Location | Cheek (facial H-zone adjacent) | High | | Size | 1.5 cm | Intermediate | | Subtype (clinical) | Nodular with ulceration | Intermediate–High | | Borders | Well-defined | Lower risk | **Clinical Pearl:** Per Harrison's Principles of Internal Medicine and NCCN guidelines, any BCC on the face — particularly with ulceration — warrants Mohs micrographic surgery as the preferred definitive treatment due to the combination of high cure rates, tissue preservation, and real-time margin control. [cite: Harrison's 21e Ch 72; NCCN Guidelines BCC v2.2024; Robbins 10e Ch 25]