Jaw, oral cavity, oropharynx

Question 1

What is the differential diagnosis of basaloid carcinomas of the head and neck?

Answer 1

1. Basaloid SCC (squamous markers+)
2. HPV-related oropharyngeal SCC (squamous markers+, p16+/HPV+)
3. Adenoid cystic (solid) - HMWCK+, CK7+, p63/p40+ in peripheral, myoep+, MYB translocation, SOX10+, ckit+
4. Basal cell adenocarcinoma (salivary gland) - CK7+, HMWCK+/-, patchy p40/myoep markers, LEF1/nuclear beta cat+/-
5. Small cell carcinoma - NE markers+, TTF1+/-, CK7+/-
6. Adamantinoma-like Ewing sarcoma (HMWCK+, CK7-, p40+, myoep-, CD99+, NKX2.2+

Question 2

What biomarker is important in oropharyngeal/tonsillar SCC?

Answer 2

HR-HPV/p16: associated with favourable prognosis and superior chemo- and radiosensitivity,

p16 IHC - needs 70% nuclear/cytoplasmic positivity

Question 3

What syndrome can odontogenic keratocysts be associated with?

Answer 3

NBCCS (if multiple)