Typically a case is likely to present with an FNA or biopsy from a suspicious lymph node and on imaging shows a tumour eroding in the nasal region. The differential diagnosis is likely to include the following:
- Distinct epidemiology – seen particularly in China (Hong Kong) and Africa
- Keratinising SCC, Non-keratinising SCC and Undifferentiated pattern. Undifferentiated nasopharyngeal carcinoma is associated with abundant lymphocytes and is sensitive to radiotherapy.
- The undifferentiated form typically shows large epithelial cells with oval and round vesicular nuclei with indistinct cell borders in a syncytial pattern and with abundant normal appearing T-lymphocytes.
- Small primary + cervial lymph nodes, little destruction or spread beyond site of origin. Mitoses, necrosis & vascular invasion not a prominent feature.
- Associated with EBV therefore shows EBER +ve. Also shows high molecular weight cytokeratin positivity (CK5/6). CK7 neg.
- Typically presents with nodal metastasis
- Rare pleomorphic carcinoma and is usually EBV negative, non keratinising and shows no significant lymphocytic infiltrate.
- Large primary +/- cervical lymph nodes, with marked destruction & spread beyond site of origin. Trabeculae, nests, sheets. Very prominent mitoses, necrosis, vascular invasion.
- Typically presents with nodal metastasis.
- IHC – EBV, CK5/6 & 13 neg. CK7 sometimes positive.
Squamous Cell Carcinoma
Non Hodgkin’s (large cell) lymphoma
Robbins and Cotran. Pathologic Basis of Disease. 8th Ed. 751pg
Gattuso et al. Differential Diagnosis in Surgical Pathology. 2nd Ed.
Dabbs. Diagnostic Immunohistochemistry. 2nd Ed.