H&N

Question 1

AFIP grading for MEC

Answer 1

Cystic component <20%: 2
PNI: 2
Necrosis: 3
at least 4mits/10hpf: 3
Anaplasia/atypia: 4
Grade:
0-4: LG
4-6: IG
>6 : HG

Question 2

Etiology of nasopharyngeal carcinoma

Answer 2

EBV

Question 3

Predisposing factors to NPC

Answer 3

1: genetic susceptibility - china, southeast asia, inuit peoples

Diet, poor hygiene, exposure to tobacco smoke, wood, grass, incense

Question 4

WHO classification of NPC

Answer 4

Nonkeratinizing (diff and undiff - subtyping here has no clinical or prognostic value)
Keratinizing SCC
Basaloid SCC

Question 5

Histology of nonkeratinizing NPC

Answer 5

Differentiated subtype: multilayered and plexiform patterns. Can resemble urothelium, cells have well-developed borders and euchromatic nuclei
Undifferentiated subtype (“lymphoepithelioma”): sheets and nests with syncytial pattern. Cells pale and vesicular nuclei and prominent nucleoli. May have spindling. Lymphocytes surround and infiltrate nests

Question 6

Histology of Keratinizing SCC variant of NPC

Answer 6

Resembles SCC arising in other H&N sites

Question 7

Histology of Basaloid SCC variant of NPC

Answer 7

2 components
- population of basaloid cells with scant cytoplasm and hyperchromatic nuclei. Los of mits and necrosis, often comedo. Commonly has mucin pools and stromal hyalinization
- differentiated SCC-type component

Question 8

Typical patterns of spread of NPC

Answer 8

Local spread into cranial vault, paranasal sinuses, intratemporal fossa, orbit
High rate of spread via lymphatics to regional LNs - most common is jugulodigastric (level IIa). Presentation of neck mass in NPC is seen in 42%
Distant mets to lungs, liver, bone (ribs/spine), in disproportionately high %

Question 9

Treatment and prognosis for patients with NPC

Answer 9

Treatment - EBRT
Prognosis - Tumor stage most important prognostic facvtor - Stage I DF5yS 98%, Stage IV 73%
Tumor type - nonkeratinizing CAs associated with better prognosis than keratinizing SCCI

Question 10

IHC for NPC

Answer 10

PanCK+
p63, p40, CK5/6+
EVER ISH+
S100, HMB45, MelanA, CD45, p16 -

Question 11

Classify fungal infections of sinonasal tract and classify features of each

Answer 11

Noninvasive:
- Fungal ball (mycetoma): not causing allergic response, typically unilateral, usually Asp
- Allergic fungal sinusitis: Allergic response, peripheral eosinophilia, elevated IgE, may be locally destructive, allergic-type mucin
Invasive:
- Acute: association with diabetes, immunosuppression, may have vascular invasion and spread to CNS; high rate of mortality
- Chronic: Usually immunocompetent, commonly diabetes. Slowly progressive, low grade invasive infection, typically Aspergillus fumigates