Oral Cancers (Exam II)

Question 1

What are the General Features of oral carcinomas ?

Answer 1

General features:

• Most common tumors of oral cavity are EPITHELIA, originating from surface cells in mouth.
• Squamous Cell Carcinoma account for over 95% of oral cancers.
• Oral cancers accounts for ~5% of ALL malignant tumors in men & ~2% in women.
• Oral cancers more COMMON in MEN than women (greater alcohol & tobacco use)
• Average age is 50-70 yrs old. (Unusual under age of 40)
• MOST common cancer in men in India (40%).
• Due to chewing Paan, a combo of Betel leaves & Areca nuts (BOTH precancerous to oral cavity)

Question 2

What are the various risk factors of oral carcinomas ?

Answer 2

1. Tobacco (both smoking & chewing): MAJOR cause of ORAL cancers in U.S.
2. Alcohol: potentiates carcinogenic effect of tobacco
3. Sunlight/UV light: cancers of lips
4. Dental irritation & poor oral hygiene
5. Immunosuppression (renal & suppression): potentiated by other risk factors
6. Leukoplakia & erythroplakia: precancerous lesions that lead to oral cancers.
7. HPV: STI cause benign (papillomas) & malignant (squamous cell) cancers, those originating in back of throat & tonsils.

• Strong link between HPV serotype 16 & 18 causing both oral & cervical cancers (both have squamous cell lining)
• Most cases of oral cancer due to HPV also have history of present/ past tobacco use

8. EBV: Found in small percentage of oral cancers ( EBV linked to hairy leukoplakia)

Question 3

General features of Cancer of the tongue?

Answer 3

• Cancer of the tongue:
• ~25-30% of all oral cancers
• MOST common site in oral cavity
• Most common location of occurrence is LATERAL & VENTRAL aspect of anterior 2/3rds (most mobile portion of tongue).
• Main etiology is tobacco & alcohol when cancer found anterior.
• Most common clinical appearance is painless ulcerated or exophytic mass.

Question 4

General features of Cancer of lower lip?

Answer 4

• ~20-25% of all oral cancers
• ~10% of cases also present with cancer on the upper lip.
• Less common occurrence in women which might relate to the protective effect of lipstick use from the sun.
• Higher survival rates, b/c it occurs on a cosmetic/aesthetic location which leads to earlier diagnosis

Question 5

General features of Cancer of the floor of the mouth?

Answer 5

• ~20% of all oral cancers
• Most common sites of occurrence is along the anterior aspect of the floor, near lingual frenulum.
• Etiology linked to tobacco & alcohol.
• Presents as ulcerated mass w/ pain, bleeding, excessive salivation
• Chance of invasion into underlying mandibular bone ( ~15-30% of cases)

Question 6

General features of Cancer of gingiva & alveolar ridge?

Answer 6

• ~6% of oral cancers
• Lower jaw/ mandibular gingiva involvement is more common than upper jaw/ maxillary gingiva.
• Edentulous areas are more commonly affected
• Presents w/ nonspecific findings, including a sore throat & difficulty opening the mouth.
• Most common clinical appearance is an ulcerated or exophytic mass.

Question 7

General features of Cancer of the hard palate?

Answer 7

• ~ 3% of oral cancers.
• RAREST primary intramural sites for development in U.S.
• In southern India, hard palate is among more common primary site because of reverse smoking (lit end inside mouth)
• Etiology linked to tobacco & alcohol use
• Presents as ulcerative or exophytic lesion w/ or w/out pain and/or bleeding
• 1/3rd of cases present w/ underlying bone invasion (late manifestation)

Question 8

Cancer of buccal mucosa

Answer 8

• ~2% of oral cancers
• Early lesions may present as irregular leukoplakic or erythroplakic plaques
• Advanced lesions appear as ulcerative & infiltrative exophytic masses
• Majority arise in middle to posterior portion of cheek/buccal mucosa w/ spread to alveolar ridge, upper & lower jaw bones, tonsils & palate.
• Etiology linked to smoking & chewing tobacco, snuff dipping & alcohol use.

Question 9

What is the MOST common locations of oral cancers related to alcohol and tobacco vs. those due to HPV?

Answer 9

Alcohol & tobacco in order from MOST common to least common:

1. TONGUE (Most Common)
2. Lower Lip
3. Floor of Mouth
4. Gingiva and Edentulous Alveolar Ridge
5. Hard Palate
6. Buccal Mucosa (Least Common)
   - Typically more anterior in the oral cavity

HPV
- Most common sites: TONSILS, base of tongue, back of throat (oropharynx), uvula, more posterior regions of oral cavity

Question 10

Define **Leukoplakia vs. Erythroplakia and their relation to cancers

Answer 10

• BOTH are PRE-CANCEROUS lesions that lead to oral cancers
• Leukoplakia = White Plaques
• Precancerous:
• asymptomatic white patch on surface of mucous membrane (not a tumor) can result in malignant transformation to squamous cell carcinoma
• EQUAL frequency in BOTH sexes
• More common after 3rd decade (30+)
• Not a diagnosis
• Cancerous:
• Locations: Buccal Mucosa, Tongue, floor of mouth
• Plaques Characteristics: solitary or multiple, vary in size, can’t be removed by scraping
• 10% = superficial
• 8% = invasive
• 20% = malignant
• Risk Factors:
• smoking
• chewing tobacco
• alcohol use

Question 11

Define **Leukoplakia vs. Erythroplakia and their relation to cancers

Answer 11

• Erythroplakia:
• More PRECANCEROUS & LESS common than Leukoplakia
• Red or dysplastic leukoplakia
• Red, velvety & eroded area w/in oral cavity mucosa
• Epithelial changes are atypical & have higher risk of malignant transformation (50%)
• SAME risk factors of Leukoplakia
• EARLY buccal mucosal lesions may present as leukoplakia or erythroplakia plaques

Question 12

Major differences between oral cancers caused by *****HPV and those related to alcohol and tobacco

Answer 12

HPV = benign papillomas or malignant
squamous cell carcinomas

-Serotypes linked to oral cancers:

• Genital (veneral) warts (condyloma acuminatum): HPV-6 & 8
• HPV 16 & 18: Oral squamous cell cancers, squamous cell cancers of cervix, penis & anus
• Most common sites: TONSILS, base of tongue, back of throat (oropharynx), uvula, more posterior regions of oral cavity
• Oral HPV+ tumors occur in YOUNG age groups than non-HPV tobacco-related groups & in white males & in non-smokers
• HPV group is the FASTEST-growing segment of oral cancer population
• # HPV related oral cancers is inc. b/c of oral sex
• Synergistic effect of tobacco, ethanol in HPV related group of oral cancers
• MORE susceptible to radiation therapy than tobacco related through = better survivability
• Most cases of oral cancer due to HPV also have a history of past or present tobacco use!

Question 13

Major differences between oral cancers caused by HPV and those related to *****alcohol and tobacco

Answer 13

• Alcohol/Tobacco (smoking and chewing) use
• Common sites: anterior in oral cavity, floor of mouth, hard palate, buccal mucosa
• Main etiology of tongue cancer is tobacco & alcohol use when found anterior
• # of tobacco related oral cancers is dec. b/c of inc. tobacco awareness
• LESS susceptible to radiation therapies
• MORE common in men b/c of increased use
• MORE common in older individuals (50-70 yo, rare before 40)
• Oral cancer is single most common cancer in MEN of India (40%) b/c of Paan, Betel Leaves, Areca Nuts

Question 14

What are the Clinical features of oral cancers and most common histologic type?

Answer 14

• MOST common TUMOR of ORAL cavity: Epithelial from surface cells w/in mouth
• MOST common ORAL cancer: Squamous cell carcinoma (95%)
• Locations (MOST to LEAST common): TONGUE > lower lip > floor of mouth > gingiva & edentulous alveolar ridge > hard palate > buccal mucosa
• SMALL lesions = asymptomatic w/ minimal clinical findings & vague symptoms
• LARGE lesions = local or referred pain depending on location, difficulty swallowing/speaking/chewing/opening → exhibit bleeding & anemia
• Lesions begin as superficial (in-situ) & takes months/years to progress to invasive lesions
• Lesions= raised, firm, pearly-white, w/ central necrosis & rolled borders
• Metastatic = bone, muscle, skin, lymph nodes, distant organs, weight loss, and S/S related to metastatic site
• Main sites of METASTASIS: SUBMANDIBULAR, superficial, deep cervical lymph nodes
• Most common blood-borne metastasis causing death: LIVER, lungs, GI, bone