GIT – Oral cavity

Dr.CSBR.Prasad, M.D.,

HERPES SIMPLEX VIRUS INFECTIONS

• Orofacial herpetic infections - HSV-1• Rarely HSV-2• Acute herpetic gingivostomatitis • Abrupt onset • Vesicles and ulcerations • Occompanied by lymphadenopathy, fever,

anorexia, and irritability

Morphology • Vesicles filled with clear, serous fluid • May ulcerate - red-rimmed, shallow ulcers• Microscopy: Tzanck prep

– Intranuclear viral inclusions – Multinucleate polykaryons

• spontaneously clear within 3 to 4 weeks • Dormant in the local ganglia (e.g., the trigeminal)• In some individuals - reactivated to produce the mild cold sore • The influences predisposing to activation:

– Exposure to ultraviolet light, – Upper respiratory tract infections– Pregnancy / menstruation– Immunosuppression and – exposure to Extremes of Temperature

Tzanck prep3Ms of Herpes: Molding, Margination of chromatin and Multinucleation

Recurrent herpetic stomatitis • Groups of small (1–3 mm) vesicles• Sites:

– The lips (Herpes labialis)– Nasal orifices– Buccal mucosa– Gingiva, and – Hard palate

• They resemble primary infections but are much more limited in duration, are milder, usually dry up in 4 to 6 days, and heal within a week to 10 days

Recurrent herpetic stomatitis

ORAL CANDIDIASIS (THRUSH)

• Three factors seem to influence the likelihood of a clinical infection:– Immune status of the individual– The strain of C. albicans present; and – Composition of an individual's oral flora

• There are three major clinical forms:– Pseudo-membranous (thrush)– Erythematous, and – Hyperplastic

• Most comon in individuals with immunosuppression– Diabetes mellitus– Organ or bone marrow transplant recipients, – Neutropenia– Chemotherapy-induced immunosuppression, or – AIDS– Broad-spectrum antibiotics

DEEP FUNGAL INFECTIONS • Fungi include:

– Histoplasmosis– Blastomycosis– Coccidioidomycosis– Cryptococcosis– Zygomycosis, and – Aspergillosis

• Patients who are immunocompromised due to:– Diabetes mellitus (esp. DKA)– AIDS – Therapies for cancer and – Organ transplantation

Precancerous Lesions

• LEUKOPLAKIA • ERYTHROPLAKIA • Submucus fibrosis

Erythroplakia

Submucus fibrosis

Submucus fibrosis

Major culprit - Gutka

Case

Oral cancer

• HNSCC is an aggressive epithelial malignancy • Sixth most common neoplasm in the world today• Very common in our country• Despite numerous advances in Tx - overall long-term survival

has remained at less than 50% for the past 50 years• The 5-year survival rate:

– Early-stage oral cancer 80%– Late-stage diseas 18%

• “field cancerization” - The rate of second primary tumors in these patients has been reported to be 3% to 7% per year

• Early detection of all premalignant lesions is critical for the long-term survival of these patients

Pathogenesis

• Tobacco• Alcoholism• HPV types 6, 16,18• Actinic radiation

Etiology: 8S 8S of oral cancer

• Syphilis• Sharp tooth• Spices• Smoking (Tobacco)• Sun light (actinic damage)• Beetle nut chewing

Molecular progression of oral cancer

Sites for oral cancer – [in the order of frequency]

Verrucous carcinoma

Microscopy

Favoured site for metastasis

• Mediastinal lymphnodes• Lung • Liver• Bones

• Note: Most commonly they tend to metastasize in the head neck regions

END