What is the correct approach for treating basal cell carcinoma (BCC) on the nose?

Treatment of Basal Cell Carcinoma on the Nose

For BCC on the nose, Mohs micrographic surgery or excision with complete margin assessment is the treatment of choice, with preservation of nasal vestibular structures being critical during excision, and radiotherapy being a viable option for periocular lesions when surgery is contraindicated or refused. 1

Analysis of Each Option

Option A: Preservation of Mucosa/Vestibular Skin - CORRECT

When excising nasal BCC, preservation of the nasal vestibule mucosa and vestibular skin is essential for maintaining nasal function and preventing stenosis. 2 The nasal vestibule represents a critical anatomical boundary that must be respected during reconstruction. 2

• Surgical planning for nasal BCC requires classification of the lateral nasal region into anatomical units, with individual reconstruction performed according to these units to achieve favorable functional and cosmetic outcomes. 3
• The nasal region tolerates various reconstruction techniques including primary closure (33% of cases), advancement flaps (28%), rotation flaps (15%), and transposition flaps (11%), all of which must respect vestibular anatomy. 2

Option B: Radiotherapy Near Medial Canthus - CORRECT

Radiotherapy is an effective treatment option for BCC near the medial canthus, particularly in patients who are unwilling or unable to tolerate surgery. 1

• RT achieves 5-year cure rates of 91.3% for primary BCC and 90.2% for recurrent disease, with long-term local control rates ranging from 84-96%. 1
• Studies specifically report good outcomes following RT treatment of BCC on periorbital skin. 1
• RT is often reserved for patients over 60 years due to concerns about long-term sequelae, but remains a valid option when surgery poses excessive risk. 1
• Critical caveat: RT is contraindicated for re-treatment of BCC that has recurred following previous RT. 1

Option C: Curettage is Best Option - INCORRECT

Curettage and electrodesiccation is absolutely contraindicated for nasal BCC and is never the "best option" for this location. 1, 4

• The nose is classified as a high-risk H-zone location where curettage shows recurrence rates of 19-27% even when mistakenly used. 4, 5
• ED&C is only appropriate for properly selected low-risk tumors in non-terminal hair-bearing locations, preferably on trunk and extremities. 4
• No histologic margin assessment is possible with ED&C, making it unsuitable for tumors requiring margin verification like those on the nose. 4
• If subcutaneous fat is reached during curettage, the procedure must be abandoned and surgical excision performed instead. 1, 4

Optimal Treatment Algorithm for Nasal BCC

First-Line Treatment

Mohs micrographic surgery (or excision with complete circumferential peripheral and deep margin assessment) is the standard of care for nasal BCC. 1, 2

• Nasal BCC requires on average 1.8 Mohs stages to achieve tumor-free margins. 2
• Morpheaform BCC on the nose has incomplete excision rates of 61.5% with standard excision, mandating Mohs surgery. 6
• The nose and ears are associated with the highest rates of positive surgical margins (50-61.5% for aggressive subtypes), making complete margin assessment essential. 6

Second-Line Treatment

For non-surgical candidates, radiotherapy achieves excellent cure rates with proper technique. 1

• Historical concerns about radionecrosis on the nasal bridge (where thin skin overlies bone) have been addressed with modern RT techniques. 1
• RT can be used successfully on many facial sites including the nose, with careful compromise between tumor destruction and acceptable radionecrosis risk (<5%). 1

Critical Surgical Considerations

• Aggressive nasal BCC requires careful examination with MRI and CT imaging to assess extent before surgery. 3
• The larger the aggressive BCC, the smaller the achievable histopathological safety margins become. 3
• Perineural infiltration is evident in approximately 17% of nasal BCCs (56 of 321 cases), requiring adjuvant RT if extensive large-nerve involvement is present. 1, 2

Common Pitfalls to Avoid

• Never use curettage for facial BCC, as the nose is a high-risk location with unpredictable subclinical extension. 4, 5
• Do not assume 4mm margins are adequate - these are only for low-risk BCC, and nasal location automatically elevates risk regardless of size. 1, 5
• Do not perform complex tissue rearrangement closures (like adjacent tissue transfers) until clear margins are verified, as re-excision through a flap is problematic. 1
• Avoid RT in patients with basal cell nevus syndrome, as it may promote growth of new BCCs. 1