Oral Pathology in Clinical Dental Practice. Robert E. Marx
Nature of disease
Premalignant alterations in the epithelium from genetic alterations in the basal cell layer due to either carcinogens, human papillomaviruses, heredity, or errors in cellular division.
Predilections
Mostly seen in adults but may be rarely seen in patients with congenital dysplastic syndromes. No sex or racial predilection is known. More commonly seen on the lateral border of the tongue or floor of the mouth.
Clinical features
A white or red-white surface lesion without induration. Pain is not usually present. Ulceration is not present unless a focal area of invasive carcinoma exists within the lesion.
Radiographic presentation
None.
Differential diagnosis
Benign hyperkeratosis, lichen planus, and candidiasis should be considered along with invasive squamous cell carcinoma.
Microscopic features
The basement membrane should be intact, and a variable degree of inflammation is seen beneath the basement membrane. The epithelium will show varying degrees of nuclear pleomorphism and cell size and a lack of cellular maturation from the basement membrane to the surface. Mitotic figures and individual cell keratinization may also be seen.
Suggested course of action
Suspicious lesions should be biopsied or referred to an oral and maxillofacial surgeon for evaluation, biopsy, and treatment.
Treatment
After confirmation by biopsy, a wide local excision with frozen section assessment of margins is accomplished. If multiple sections of the main specimen identify an area of invasive squamous cell carcinoma, the area is re-treated with a re-excision and a neck dissection is considered after a metastatic workup is accomplished.
Hypertrophic and Striaform Lichen Planus
Nature of disease
A mild T cell–mediated autoimmune disease that attacks the basal cell layer and basement membrane at the interface between the epithelium and the subjacent connective tissue.
Predilections
Adults over 40 years of age. No sex or racial predilection is known. Mostly seen on the buccal mucosa but may also be seen on the tongue and attached gingiva.
Clinical features
The striaform type presents as asymptomatic, lacy white lines referred to as Wickham striae. The hypertrophic type presents as an asymptomatic, irregular white hyperkeratotic patch.
Radiographic presentation
None.
Differential diagnosis
The striaform type is distinctive but may resemble hereditary benign intraepithelial dyskeratosis or candidiasis. The hypertrophic type appears most like clinical leukoplakia, and therefore epithelial dysplasia, carcinoma in situ, proliferative verrucous leukoplakia, verrucous carcinoma, and invasive squamous cell carcinomas should be considered.
Microscopic features
Both will show acanthosis with hyperkeratosis and a bandlike infiltrate subjacent to the basement membrane consisting of mostly (≥90%) lymphocytes as well as a disrupted basement membrane.
Suggested course of action
Clinically apparent striaform lichen planus requires reassurance to the patient of the usual mild and nonprogressive nature of the disease as well as its nonpremalignant biology. Hypertrophic lichen planus requires an incisional or excisional biopsy to rule out more serious diseases.
Treatment
No specific treatment is required.
Secondary Syphilis (Mucous Patches)
Nature of disease
The systemic second phase of an infection caused by Treponema pallidum.
Predilections
In adults, secondary syphilis is a systemic progression from a primary syphilis lesion known as a chancre. In newborns, secondary syphilis arises from transplacental transmission from an infected mother to the fetus, and thus the child is born with secondary syphilis. No sex or racial predilection is known.
Clinical features
In adults, the lesions will appear as asymptomatic, flat, red-white lesions or patches of erythema with a pale peripheral ring. In newborns and children, T pallidum usually causes developmental disturbances such as the classic triad of mulberry molars, notched incisors, and tapered incisors (screwdriver teeth) known as Hutchinson’s triad. Additionally, saber-shaped shins, rhagades, interstitial keratitis, and a saddle nose deformity may variably be seen.
Radiographic presentation
None.
Differential diagnosis
Mucous patches of secondary syphilis will appear similar to candidiasis and lichen planus. Erythema multiforme may also be considered if skin lesions are present.
Microscopic features
Biopsies of mucous patches will usually show a plasma cell infiltration among a proliferation of small blood vessels.
Suggested course of action
Suspected cases should be referred to an infectious disease specialist and/or submitted for serologic testing for a VDRL (Venereal Disease Research Lab) test and an FTA (fluorescent treponemal antibody) absorption test.
Treatment
Secondary syphilis is usually treated with one dose of 1.2 to 2.4 million units of benzathine penicillin intramuscularly. In penicillin-allergic patients, doxycycline 100 mg orally twice daily for 14 days or oral erythromycin 500 mg four times daily for 14 days can be substituted.
Hereditary