What is the recommended workup for a patient suspected of having squamous cell carcinoma (SCC)?

Workup for Squamous Cell Carcinoma

Begin with a diagnostic biopsy of any suspicious lesion to confirm the diagnosis histologically before initiating any treatment, as this is essential for establishing the diagnosis, determining high-risk features, and guiding appropriate management. 1

Initial Clinical Assessment

History and Physical Examination

• Perform a complete skin examination to identify additional concurrent precancers or other skin cancers at sun-exposed sites 2
• Conduct a regional lymph node examination specifically for squamous cell carcinoma, as nodal metastasis significantly impacts prognosis and treatment 2
• Document duration and symptoms of the lesion, particularly for chronic non-healing wounds 2
• Assess for immunosuppression history (HIV, organ transplantation, immunosuppressive therapy) as this increases risk 3

Diagnostic Biopsy

• Obtain tissue biopsy as the mandatory first step using shave biopsy or excisional biopsy techniques 1
• Ensure the biopsy includes deep reticular dermis, as infiltrative histology may only be present at deeper advancing margins and superficial biopsies frequently miss this aggressive component 2
• The specimen must be adequate in size and depth to provide pathology elements for accurate diagnosis and risk stratification 1

Critical Pitfall: Never treat suspected SCC with cryotherapy or other modalities without first obtaining a diagnostic biopsy, as this leads to inadequate treatment and loss of prognostic information needed for appropriate follow-up 1

Risk Stratification

After histopathological confirmation, classify the tumor as low-risk or high-risk based on clinical and pathological parameters 1:

High-Risk Features to Identify:

• Tumor size ≥2 cm (or ≥5 cm for extensive disease) 2
• Poor differentiation on histology 2
• Perineural invasion 2
• Depth of invasion into subcutaneous tissue 2
• Location on high-risk anatomic sites (ear, lip, temple) 2

Lymph Node Assessment

For Palpable or Suspicious Lymph Nodes:

• Perform fine-needle aspiration (FNA) or core-needle biopsy of clinically suspicious neck masses or regional lymph nodes 2
• If FNA is negative in head and neck region, consider reevaluation with imaging, repeat FNA, or open lymph node biopsy 2
• If FNA is negative in trunk/extremity region but clinical suspicion remains high, proceed to open biopsy 2
• Ultrasound-guided FNA improves diagnostic accuracy for accessible lymph nodes 3

For Non-Palpable Lymph Nodes in High-Risk Cases:

• Consider imaging studies to detect subclinical lymph node metastases 4
• Sentinel lymph node biopsy may be considered in select high-risk cases, though its role remains evolving 2, 4

Important Note: Elective nodal dissection without proven nodal involvement should not be performed due to associated morbidity 2

Imaging Studies

For Primary Tumor Assessment:

• Larger tumors (≥5 cm) or those overlying difficult anatomical sites should be imaged to assess extent and involvement of underlying structures (tendons, nerves, vessels) 2
• MRI is the investigation of choice; if unavailable, use CT scanning 2
• For oropharyngeal SCC: obtain high-resolution cross-sectional imaging with contrast-enhanced CT of the neck or MRI 2

For Distant Metastasis Staging:

Indicated for tumors ≥5 cm or symptoms suggesting metastatic spread (bone pain, abnormal liver function, breathlessness) 2:

• PET-CT is preferred where available for comprehensive staging 2
• If PET-CT unavailable, obtain CT or MRI of chest, abdomen, and pelvis 2
• Chest evaluation with chest CT or PET-CT should be performed as the next diagnostic step 2
• If CT unavailable, consider abdominal ultrasonography and/or bone scanning 2

Imaging Caveat: In certain populations (e.g., epidermolysis bullosa patients), PET scanning may show nonspecific uptake from chronic wounds, reactive lymph nodes, or inflammation; combination with CT helps clarify significance 2

Additional Workup for Specific Presentations

For Oropharyngeal SCC:

• Perform fiberoptic laryngopharyngoscopy as part of multidisciplinary evaluation 2
• Conduct high-risk HPV testing routinely on biopsy of primary site or lymph nodes 2
• Obtain pretreatment speech and swallowing consultation with objective measurements using modified barium swallow study, video-fluoroscopic swallowing study, or fiberoptic endoscopic evaluation 2

For Deep Extension Suspected:

• Perform preoperative imaging to assess extent of soft tissue or bony involvement when skin cancers present with appearance of deep extension into bone or orbit 2

Multidisciplinary Discussion

All patients with confirmed SCC should be discussed at a multidisciplinary meeting involving dermatologist, surgeon, histopathologist, and oncologist for review of histology and planning of staging and treatment 2

For oropharyngeal cases, the team should include head and neck surgeon, radiation oncologist, medical oncologist, dentist, rehabilitative specialists, social work, and pain/palliative care specialists 2

Follow-Up Planning

• After diagnosis and treatment, monitor for recurrence and new skin cancers 1
• Annual skin examinations at minimum are recommended for all patients with history of SCC 1
• For high-risk patients or those with prior SCC, more frequent surveillance (every 3-6 months) may be warranted 2