Larynx

Question 1

Vocal cord polyp

Answer 1

• Common benign laryngeal lesion, also known as laryngeal nodule or singer’s nodule
• Patients of all ages, even in pediatric population
• More common in heavy smokers, patients with history of chronic irritant inhalation or singers, due to inflammation, allergic or immunologic causes, possibly secondary to hemorrhage
• Can be secondary to irritation from gastroesophageal reflux disease

Macro:
* Smooth
* Round
* 1 - 3 mm growths on true vocal cords, often on anterior third

Micro:
* Polyps and nodules are histologically indistinguishable, although polyps tend to be larger
* Early stage lesions –> myxoid edematous stromal changes and fibroblastic proliferation
* Later stage lesions –> stromal hyalinization and telangiectatic blood vessels
* Overlying squamous mucosa is usually unremarkable or can show mild reactive atypia

Question 2

Laryngeal Papilloma

Answer 2

• Benign, exophytic squamous epithelial proliferation
• Composed of branching papillary fronds
• Central fibrovascular cores lined by hyperplastic nonkeratinizing squamous epithelium
• Usually associated with low risk human papilloma virus (HPV) infection; in particular, genotypes 6 and 11

Clinical:
Can be divided into 4 subtypes:
* juvenile solitary
* juvenile multiple –> tends to spread to epiglottic and subglottic area
* adult solitary
* adult multiple
* Children: triad of progressive hoarseness, stridor and breathing difficulty
* Adults: most commonly hoarseness
* Symptoms tend to be more severe in children, due to the rapid growth of lesions and propensity for airway obstruction
* In severe cases, patients develop airway obstruction and respiratory distress

Macro:
* Can be solid or multiple, variable size
* Exophytic cauliflower-like, sessile or pedunculated pinkish-whitish masses with bosselated surfaces
* Mucosa appears velvety in microscopic (small) papillomas

Micro:
* Finger-like projections or multiple fronds with a central fibrovascular core
* Covered by benign hyperplastic stratified squamous epithelium
* Basal and parabasal hyperplasia
* Increased mitotic figures in the basal and parabasal layers
* Koilocytic changes in upper layer: may be pronounced or subtle
* Surface keratinization: absent to minimal
* Malignant transformation is characterized by aberrant (paradoxical) keratinization, marked cytological atypia, focal necrosis, increased mitoses and atypical mitoses not limited to the basal and parabasal layers, as well as invasive growth pattern

Question 3

Laryngeal Carcinoma

Answer 3

Risks
* Tobacco smoke
* Alcohol
* Coal dust
* Asbestos
* Ionising radiation
* HPV
* FHx

Sites
* Glottis - 51%
* Supraglottis - 32%
* Overlapping lesion of larynx - 4%
* Subglottis - 2%
* Laryngeal cartilage - 1%

Micro:
Mostly Squamous
* Invasion indicated by desmoplasia around malignant squamous cells, often with keratinization at periphery
* Progression of columnar epithelium areas is similar to squamous cell carcinoma of cervical or lung
* Progression of vocal cord tumors is similar to squamous cell carcinoma of skin or esophagus
* Well, moderate or poorly differentiated, based on degree of keratinization, pearl formation, intercellular bridges and mitotic activity
* Smaller tumors are usually better differentiated