272. H/N Cancer

Question 1

H/N Cancer

• epidemiology
• Risk Factors

Answer 1

Epi: RARE (3% of all new cancers are in oral cavity and pharynx), but 6th leading cause of cancer death, M > F, 65% long term survival

RF

1. AGE >50
2. TOBACCO
3. ALCOHOL
4. VIRAL: EBV (nasopharyngeal) and HPV (oropharyngeal)
5. Plummer-Vinson Syndrome (Iron deficiency, glossitis, esophageal webs(
6. Fam Hx (RARE) [Fanconi Anemia]

Question 2

What are the 2 large and distinct subtypes of H/N Cancer?

Answer 2

1. HPV - Related
   - HPV 16 and viral oncogenes (E6/7 - p53/Rb)
   - overexpression of P16 due to E7 binding Rb = disrupts Rb-E2F interaction
   - restricted to oropharynx
   - distinct mLc markers
   - GOOD prognosis
   - pts: young, healthy
2. Enviro - Related
   - Enviro mutagens (smoking, alcohol)
   - throughout oral mucosa/field cancerization
   - distinct mLc markers
   - POOR prognosis
   - secondary cancers common in field

Question 3

H/N CP, dx

Answer 3

• Lesion in mouth
• Hoarsenss, Sore throat
• difficulties in chewing, swallowing, speaking
• palpable mass in neck
• Ear pain (Otalgia)
• Cranial neuropathies

Dx: Indirect Laryngoscopy (use mirrors to look), Laryngoscopy + FNA Biopsy, Panendoscopy (larynx, esophagus, bronchus) under anesthesia
Path: SCC +/- keratinization: poorly differentiated, hyperchromatic nuclei, high N:C ratio, KERATIN PEARLS
HPV: stains p16
CT - assess extent, LAD
PET/CT - staging

Question 4

H/N Cancer staging

Answer 4

TNM
T1, T2 - small localized
T3 - large invading adjacent structures
T4 - locally advanced and invading

N1: ipsilateral single LN <3cm
N2: large or multiple LN <6cm
N3: LN > 6cm

Stage IVC - Metastatic Disease (distant mets)
- Stage IVA/B are only locally advanced

Question 5

H/N Cancer Tx

• by stage
• adverse effects

Answer 5

Early Stage (I, II, localized): RT or Surgery (80-90% have long term survival/cure)

Locally Advanced (III - IVB): multimodality tx (surgery, chemotx, RT) - chemo preferred due to better QoL than in surgery, adding chemo to RT improves survival

Metastatic/Recurrent: NO surgery/RT - needs PALLIATIVE chemo, immune tx, targeted tx

Radiation causes MUCOSAL TOXICITY
RT: Skin Toxicity (hyperpigmentation, dry, moist desquamation, maculopapular skin lesions)
- xerostomia, tooth caries, loss of taste, osteonecrosis

Question 6

Prognosis: Which cancers in H/N have better survival?

Answer 6

HPV+ better survival
- detect with E6/E7 mRNA detection

HPV - worse prognosis, field cancerization (rise of secondary cancers in same field - cancerous and precancerous)