Eileen - oral cancer, larynx anatomy Flashcards
What are the two main signs of precancerous and benign neoplastic disease?
Leukoplakia
Erythroplakia
Define leukoplakia.
A white patch or plaque that can’t be scraped off and can’t be characterised clinically or pathologically as any other disease
How many leukoplakial lesions are pre-malignant?
5-25%
Where a leukoplakial lesion most often found within the mouth?
Vermilion border of the lower lip
Buccaneers mucosa
Hard and soft palates
Not that often seen on the floor of the mouth
Describe erythroplakia
Red velvety patches of epithelial atrophy and pronounced dysplasia
Where is erythroplakia most commonly seen within the oral cavity?
On the buccal mucosa or the palate
What are the possible head and neck cancers?
Squamous cell carcinomas - 95%
Adenocarcinomas
Melanomas
Various carcinomas
How do SCCs arise pathologically?
Derived from epithelial lining - it’s an aggressive epithelial malignancy
May arise from existing dysplasia (erythroplakia or leukoplakia)
What is the long-term survival rate for squamous cell carcinoma - and why?
50%- it’s so low because oral cancer are often quite advanced by the time they are diagnosed - also, multiple primary tumours often develop
What are the risk factors for oral cancers?
Smoking Alcohol HPV - at least half of oral cancers (particularly if they involve the tonsils, base of tongue or the orophyarynx, involves oncogenic variants of HPV) Genetics Actinic radiation Nutritional deficiency
Why will HPV-associated HNSCC surpass that of cervical cancer in the next decade?
Anatomical sites of origin (tonsils, base of tongue, orophyarynx) aren’t readily accessible not to cytology cal screening - unlike the cervix
Describe the macroscopic structure of the HNSCC.
Raised modular lesions
Central ulceration with hard raised edges
Describe the microscopic structure of the HNSCC.
The tumour is well-differentiated and keratinising
Where are the sites that a HNSCC often forms?
Lips - recognised early and amenable to surgery Tongue - lateral border of anterior two thirds
Cheek or floor of mouth - asymptomatic, resulting in extensive local invasion and making surgical removal difficult
Describe the five stages of histological progression.
Normal Hyperplasia/hyperkeratosis Mild/moderate dysplasia Severe dysplasia/carcinoma in situ Squamous cell carcinoma
Why do people not often report lesions in their mouths?
Incomplete understanding that small, asymptotic lesions can have massive malignant potential
Dentists aren’t properly performing a basic oral cancer examination to achieve the early detection
How could more people with these lesions be identified at an earlier stage?
Health education programmes
Tools to improve screening methods
Dentists perform visual and tactile examination Identification of high risk individuals and implementation of efficient chemoprevention and molecular targeting strategies
What influences the time until diagnosis?
Socioeconomic status
Patient reluctance to go to a doctor
Professional delay in diagnosis and treatment
Where are the superficial lymph nodes and what do they drain?
They form a ring around the head
Drain the face and the scalp
Where are the occipital nodes and what do they drain?
Near the attachment of the trapezius to the skull
Associated with the occipital artery
Drain the posterior scalp and neck
Where are the post auricle nodes and what do they drain?
Posterior to the ear and near the attachment of the sternocleidomastoid muscle
Associated with the postauricular artery
Lymphatic drainage is from the postero-lateral part of the scalp
Where are the preauricular nodes and what do they drain?
Anterior to the ear
Associated with superficial temporal and transverse facial arteries
Drains the anterior auricle, anterolateral scalp and upper half of face, eyelids and checks
Where are the submandibular nodes and what do they drain?
Inferior to the border of the mandible
Associated with the facial artery
Drains the structures along the path of the facial artery, as well as gums, teeth and tongue
Where are the sub entail nodes and what do they drain?
Inferior and posterior to the chin
Drains the central part of the lower lip, chin, floor of mouth, tip of tongue and lower incisor teeth
Where do the occipital and postauricular lymph nodes drain to?
Superficial cervical lymph nodes
Where do the preauricular, submental and submandibular nodes drain to?
The deep cervical lymph nodes
Where are the superficial cervical lymph nodes, where do they drain to?
They run along the external jugular vein on the superficial surface of the sternocleidomastoid muscle
They drain to the deep cervical nodes
Where are the deep cervical lymph nodes, and where do they drain?
They form a chain along the internal jugular vein
Drain to jugular trunks - these empty into the right lymphatic duct on the right and the thoracic duct on the left
The tendon of which muscle divides the deep cervical lymph nodes in upper and lower groups?
Intermediate tendon of the omohyoid muscle
