What is the recommended approach for skin cancer removal in a patient with epidermolysis bullosa?

Skin Cancer Removal in Epidermolysis Bullosa

Surgical excision is the standard treatment for squamous cell carcinoma (SCC) in patients with epidermolysis bullosa (EB), and all cases must be discussed at a multidisciplinary meeting with dermatology, plastic surgery, histopathology, and oncology before proceeding. 1

Multidisciplinary Team Approach

• Every EB patient with SCC requires multidisciplinary team discussion before treatment to review histology and plan staging and surgical approach 1
• The core team must include: dermatologist, plastic surgeon, histopathologist, and oncologist 1
• This collaborative approach is essential given the complexity of managing fragile skin, aggressive tumor biology, and high recurrence rates in EB patients 1

Pre-Operative Tumor Assessment

Primary Tumor Imaging

• For SCCs ≥5 cm or overlying difficult anatomical sites (tendons, nerves, vessels), obtain MRI to assess tumor extent 1
• If MRI unavailable, use CT scanning as second-line imaging 1
• This imaging is critical because EB-associated SCCs are often more aggressive and deeper than they appear clinically 1

Regional Lymph Node Evaluation

• If lymph nodes are clinically palpable, perform ultrasound-guided fine needle aspiration (FNA) to assess for metastatic disease 1
• If FNA is inconclusive after repeated attempts, proceed to surgical biopsy 1
• Important caveat: EB patients frequently have enlarged lymph nodes from chronic inflammation and wound infection, not malignancy 1
• If FNA is negative, re-examine lymph nodes every 3 months and rebiopsy if further enlargement occurs 1
• Clinical evaluation may be difficult with significant axillary scarring; ultrasound evaluation is helpful in these cases 1

Sentinel Lymph Node Biopsy Considerations

• Sentinel lymph node biopsy (SLNB) may be performed but has limited utility in EB patients 1
• All reported SLNB cases in EB have been negative for nodal SCC to date 1
• No evidence exists that SLNB results inform prognosis or that regional lymph node clearance in SLNB-positive patients influences clinical outcome 1

Staging for Distant Metastases

Staging is required for:

• Primary SCC ≥5 cm in maximum diameter 1
• Symptoms suggesting metastatic spread (localized bone pain, deranged liver function tests, breathlessness) 1

Staging approach (in order of preference):

1. FDG-PET with CT scanning is the preferred modality 1
   • Critical interpretation note: Nonspecific isotope uptake occurs in EB from chronic wounds, reactive lymph nodes, esophagus, and bone marrow; combination with CT helps clarify significance 1
2. If PET unavailable, use CT or MRI of chest, abdomen, and pelvis 1
3. If CT unavailable, use abdominal ultrasonography and/or bone scanning 1

Surgical Treatment Options

Primary Surgical Approaches

Surgical excision is the standard treatment, with several technique options: 1

• Wide local excision 1
• Mohs micrographic surgery 1
• Amputation of digit or limb 1

No evidence demonstrates superiority of one technique over another; choice depends on anatomical location, tumor size, and functional considerations 1

Critical Decision-Making

• Open discussion with the patient is paramount to balance the need for extensive or radical surgery against functionality and ability to perform activities of daily living 1
• In some cases, amputation may be favored over wide excision when more aggressive surgery is believed to reduce recurrence risk, but functional considerations and patient preference must guide decisions 1

Wound Closure Options

Multiple approaches exist without clear evidence of superiority: 1

• Partial or full-thickness skin grafting 1
• Allografts or artificial skin equivalents 1
• Healing by secondary intention 1
• Choice depends on wound size, anatomical location, availability of intact donor skin, and availability of alternative graft materials 1

Regional Lymph Node Management

• If lymph node biopsy is positive for metastatic SCC, perform regional lymph node dissection, ideally at the same time as primary tumor excision 1
• Elective nodal dissection (without proven nodal involvement) should NOT be performed due to morbidity from regional lymphedema, which exacerbates blistering, chronic wounds, and exudate levels in EB patients 1
• Regional lymph node clearance should be undertaken if nodal disease is confirmed, though no evidence shows it affects prognosis; however, removal may reduce subsequent ulceration and local complications from tumor deposits 1

Anesthetic Considerations

• Use face mask for general anesthesia when possible to avoid airway complications from intubation trauma in patients with fragile mucous membranes 2
• Surgical treatment is challenging for both surgeon and anesthetist due to skin fragility and abnormal tumor bed 2

Alternative Treatment Modalities

Radiotherapy

• Radiotherapy may be useful for palliation in inoperable EB SCCs or for subcutaneous, lymph node, and distant metastases 1
• Must be delivered in smaller fractions to minimize risk of severe skin desquamation in EB patients 1

Electrochemotherapy

• Electrochemotherapy (ECT) with bleomycin has shown promise as an alternative treatment, with complete response in some cases and mild adverse effects (local pain, erythema, ulceration) 3
• This represents a potential option when surgery carries excessive risk 3

Systemic Therapy

• Conventional chemotherapy may provide some palliative benefit but risks may outweigh benefits 1
• EGFR antagonists and tyrosine kinase inhibitors may be useful for palliation in advanced EB SCCs 1

Common Pitfalls to Avoid

• Do not perform elective lymph node dissection without proven nodal disease – the morbidity from lymphedema will worsen the patient's EB symptoms 1
• Do not rely solely on clinical examination of lymph nodes – chronic inflammation causes frequent false positives; always confirm with FNA or biopsy 1
• Do not misinterpret PET scan results – remember that chronic EB wounds cause nonspecific uptake that can mimic metastatic disease 1
• Do not underestimate the need for preoperative imaging in large tumors (≥5 cm) or those over critical anatomical structures 1
• Do not proceed with surgery without multidisciplinary team input – the complexity of these cases requires collaborative planning 1