Clinical history: 49yo M with no past medical history, presents with left then right neck lumps, a blocked left ear and intermittent blood-tinged saliva. Clinical examination reveals bilateral enlarged cervical lymph nodes. The largest one is a left level II cervical lymph node measuring 3-4 cm in size.
Ultrasound-guided fine needle aspiration of the left level II cervical lymph node was performed.
- Variably cohesive groups of uniform, moderately pleomorphic malignant cells
- Singly dispersed malignant cells are seen.
- The malignant cells have vesicular, occasionally eccentric nuclei, prominent nucleoli and generally scant cytoplasm.
- Smaller lymphocytes are seen in the background.
- No granulomas or necrosis present.
Diagnostic considerations at this point
- Metastatic poorly differentiated/undifferentiated carcinoma
- Non-Hodgkin lymphoma with medium to large cell morphology
- Metastatic melanoma
- Cell block shows singly scattered and very small clusters of tumour cells.
- The tumour cells are positive for AE1/3.
Nasoendoscopy shows diffuse postnasal space irregular prominence extending to bilateral fossa of Rosenmuller. A biopsy of the left postnasal space was taken and shows the following:
- Diffuse sheets of tumour cells with crush artefact
- The better-preserved tumour cells show enlarged and irregular vesicular nuclei, prominent nucleoli and scant cytoplasm.
- Admixed lymphocytes are seen.
- The tumour is positive for AE1/3 and EBER-ISH (as shown above).
- It is also positive for CAM5.2 and CD99 (the latter showing only cytoplasmic staining with no diffuse strong membranous staining).
- The tumour is negative for CD3, CD20, p63, p40, synaptophysin, chromogranin, CD56, S100, desmin and NUT1. INI1 is retained.
Diagnosis
Left postnasal space, biopsy: Non-keratinizing (nasopharyngeal) carcinoma, undifferentiated type (EBER-ISH positive)
- The tumour cells in the cervical lymph node FNA morphologically resemble those seen in the postnasal space biopsy.
- Like the postnasal space tumour, the tumour cells in the cervical lymph node FNA are also AE1/3 positive.
DIAGNOSIS
Left level II cervical lymph node, FNA:
Poorly differentiated/undifferentiated malignant cells present, compatible with metastatic non-keratinizing (nasopharyngeal) carcinoma, undifferentiated subtype
Case writer: Dr Nicholas Tan