CytoPage Quiz – 2024 Dec – NUS Pathweb

CytoPage Quiz 2024 Dec

Question:

Which of the following head and neck cytology specimens show malignant squamous cells?

Case A
Case B
Case C
Case D
None of the above

Case A (Papanicolaou, 400x): 72 year old Chinese man with a history of left alveolar SCC s/p resection and adjuvant radiotherapy. Right cervical LN, US-guided FNA.

Case B (Hemacolor, 400x): 30 year old Chinese lady with a painful left neck swelling for 3 weeks. US shows a 3 cm unilocular cystic lesion along the right neck. Right lateral neck lump, US-guided FNA.

Case C (Papanicolaou, 400x): 62 year old Malay man with a smoking history of 30 pack years, now presents with a right angle of jaw swelling for 6 months. US shows a 2.5 cm heterogenous solid-cystic lesion. Right parotid lump, US-guided FNA.

Case D (Hemacolour, 400x): 70 year old Chinese man presented with a right neck lump for 4 months’ duration. He also reported a significant loss of weight of over 10kg in the past 3 months, with loss of appetite. US reveals an enlarged 3 cm lymph node in the right neck, with cystic change. Other smaller sub-centimetre matted nodes can be seen. Right cervical LN, US-guided FNA.

Answer

Answer: Case D

Case D shows a mixed lymphoid background with atypical cells with orangeophilic cytoplasm in a case of metastatic squamous cell carcinoma to the lymph node.

Even though no known primary cancer was noted on history taking, examination findings, and initial investigations, squamous cell carcinomas of the oropharyngeal region can be rather insidious at onset, and it is not uncommon for patients to present upfront with metastases, with the metastatic deposit often the first sign of disease. In some cases (such as our patient), the metastatic deposit may be even larger than the primary tumour.

The patient subsequently underwent further imaging, which elicited a 1 cm base of tongue SCC.

In such cases, it may be prudent to obtain a cell block to perform p16 immunohistochemistry, if an oropharyngeal primary is suspected. The p16 for this case was ultimately negative.

Atypical cells can also be seen in non-malignant conditions. In case A, a large squamoid cell is seen with a bizarre cell shape as well as a bizarrely shaped nucleus. However, this cell is exhibiting radiation-induced changes. Do note that while radiation-induced changes can lead to bizarre cell shapes, enlarged cells, or nuclear pleomorphism, the general nuclear-to-cytoplasmic ratio for these cells tend to remain low. It would be important to look for a history of radiation to the affected area!

Case B shows bland squamous cells in an inflamed branchial cleft cyst.

Case C shows degenerate and orangeophilic cells which can be sometimes seen in Warthin tumour. Associated classical oncocytic cells are also present and are a helpful clue.