What is the next step in managing an adult with a supraclavicular lymph node (LN) greater than 2cm and inconclusive Fine Needle Aspiration Cytology (FNAC) results?

Core Needle Biopsy is the Next Step

For an adult with a supraclavicular lymph node >2cm and two inconclusive FNAC results, core needle biopsy should be performed before considering excisional biopsy or proceeding directly to open biopsy. 1

Rationale for Core Needle Biopsy

Why FNAC Alone is Insufficient

• Supraclavicular lymphadenopathy carries a 71-92% malignancy rate in adults, making definitive tissue diagnosis critical 2, 3
• FNAC has a 21% non-diagnostic rate for supraclavicular nodes, and your patient has already had two inconclusive attempts 2
• When FNAC is non-diagnostic despite adequate sampling (which two attempts suggest), the next step is obtaining more tissue architecture, not repeating the same procedure 3

Advantages of Core Needle Biopsy Over Other Options

• Core needle biopsy provides histological architecture that FNAC cannot, which is essential for distinguishing lymphoma subtypes from metastatic carcinoma and for molecular profiling 3, 4
• Core needle biopsy has 92% sensitivity for lymphoma diagnosis compared to 74% for FNAC, making it superior when lymphoma is in the differential 5
• It allows for immunohistochemistry, flow cytometry, and next-generation sequencing studies that are increasingly necessary for treatment planning in the era of precision medicine 4

Why Not Excisional Biopsy First

• The American Academy of Otolaryngology-Head and Neck Surgery guidelines explicitly recommend FNA (or core biopsy as an extension) instead of open biopsy for neck masses at increased risk for malignancy 1
• Open biopsy should be reserved for when less invasive methods fail, and you haven't yet exhausted tissue sampling options 1
• If this proves to be metastatic squamous cell carcinoma from an occult head and neck primary, examination under anesthesia of the upper aerodigestive tract should precede open biopsy to identify the primary site 1

Clinical Algorithm

Immediate Next Steps

1. Order ultrasound-guided core needle biopsy of the supraclavicular node 5, 4
2. Request tissue for multiple studies: routine histology, immunohistochemistry panel, and consider requesting tissue banking for potential molecular studies 4
3. Obtain CT neck with contrast (if not already done) to evaluate for a primary site and assess the full extent of lymphadenopathy 1

If Core Biopsy is Also Non-Diagnostic

• Proceed to excisional biopsy, but only after examination under anesthesia of the upper aerodigestive tract if imaging suggests possible head and neck primary 1
• Ensure the incision is planned to allow subsequent complete lymph node dissection if needed 1

Critical Pitfalls to Avoid

• Do not prescribe empiric antibiotics without clear signs of bacterial infection (warmth, erythema, fever, tenderness), as this delays malignancy diagnosis and provides false reassurance 1
• Do not assume a cystic component on imaging means benign disease—cystic metastases from HPV-positive oropharyngeal squamous cell carcinoma commonly present as supraclavicular masses in younger adults without traditional risk factors 1
• Do not proceed directly to open biopsy without attempting core needle biopsy first, as this violates established guidelines and increases morbidity 1

Role of Multidisciplinary Team Discussion

• While MDT discussion is valuable, it should not delay obtaining definitive tissue diagnosis 1
• Present the case to head and neck MDT after core biopsy results are available, as this allows for more informed treatment planning 1
• MDT review becomes essential if the diagnosis remains uncertain after core biopsy or if complex surgical planning is needed 1