Benign Neoplasms Flashcards
Epithelial
HPV
Human Papilloma Virus (HPV) etiology. All are papillary or verrucous growths.
- Papilloma
exophytic, often pedunculated, pink to white, most common site: soft palate.
- Verruca vulgaris (common wart) usually HPV2, similar to papilloma.
Many patients have verruca on hands.
- Condyloma Acuminatum“venereal warts” usually HPV 6/11, often multiple,
less exophytic than papillomas.
All these benign epithelial tumors treated by removal.
Epithelial
Keratoacanthoma (KA)
Clinical and histological features similar to skin cancer (squamous cell carcinoma),
considered reactive, not neoplastic.
Sun exposed areas of head and neck, ↑ older patients, 10% on lips/have been
reported intraorally. Rapid growth, often umbilicated with rolled borders
Natural history: Involution and healing.
Mesenchymal
most look identical clinically and present as asymptomatic, slowly growing submucosal masses
Treatment of most benign mesenchymal tumors is excision.
Mesenchymal
Connective Tissue
1. Fibroma
2. Lipoma
3., Verruciform xanthoma
Connective Tissue
- Fibroma
most common but covered in reactive tumors
- Lipoma
Benign neoplasm of fat, may appear yellowish, very common in skin, less so orally
- Verruciform xanthoma
Reactive lesion with predilection for hard palate or gingiva. Most common orally but reported on skin and genitals
Surface irregular (verrucous, “verruciform”)
Pink to white
Histology: Epithelium displays papillary hyperplasia. Connective tissue papillae contain phagocytic cells which have engulfed lipid (xanthoma cells)
Mesenchymal
Muscle
1. Leiomyoma
2. Rhabdomyoma
3. Granular cell tumor
4. Congenital epulis of the newborn
Muscle
- Leiomyoma (angioleiomyoma) (vascular leiomyoma)
Benign neoplasm of smooth muscle
Common in uterus (“fibroids”), rare orally, most normal color, can be reddish to purple
- Rhabdomyoma
Benign neoplasm of skeletal muscle,↑ heart, rare orally, ↑ tongue
- Granular cell tumor
Originally thought to arise from muscle (granular cell myoblastoma) now thought to be of nerve origin, possibly sheath.
Common in skin and orally,
↑↑ tongue (most common site) but can affect other sites, may be firm and “fixed”, not freely movable on palpation.
Histology: Large polygonal cells with granular cytoplasm, about 1/2 cause overlying epithelium to react in a pattern that simulates carcinoma called pseudoepitheliomatous hyperplasia (PEH)
- Congenital epulis of the newborn
Congenital tumor of anterior alveolar ridge
Mx: Md/2:1 F:M/8-10:1
Varied size
Histology: Identical cells to granular cell tumor but cells don’t react to immunohistochemical markers for nerve, No PEH
May regress if incompletely “excised”
Mesenchymal
Nerve (5)
- Traumatic Neuroma
2. Neurofibroma
Neurofibromatosis
3. Neurilemmoma
4. Melanotic neuroectodermal tumor of infancy
5. Multiple Endocrine Neoplasia Type 3 (MEN 3) (2b)
- Traumatic Neuroma
not neoplasm but aberration of healing following trauma.
Mass of tangled regenerating nerve in scar tissue
↑ lateral and anterior borders of tongue, lower lip, at mental foremen palpation produces pain
- Neurofibroma
Benign neoplasm occurring in a nerve and composed of Schwann cells, axons and fibrous tissue
Can occur in most tissues and organs of body, including oral cavity, soft tissue and bone, most asymptomatic
Neurofibromatosis (Von Recklinghausens Disease of Skin) a developmental condition of neuroectoderm ranging from simple skin pigmentation to widespread involvement of central and peripheral nervous system. 1/2 inherited as autosound dominant trait, other 1/2 somatic mutations.
(Gene for most on chromosome #17)
Neurofibromas of skin and mucosa
Light brown skin pigmentation (cafe-au-lait spots)
Axillary freckling, pigmentary defects of iris (Lisch spots)
1-5% of patients develop malignancy in their neurofibromas.
- Neurilemmoma (Schwannoma)
Benign encapsulated neural neoplasm arising within the sheath or
neurilemma of a peripheral nerve painless, often freely movable
Histology: Encapsulated neoplasm
Antoni A: Acellular areas of replicated basement membrane
material surrounded by Schwann cell nuclei
Antoni B: Haphazardly arranged spindled Schwann cells in
loose stroma.
- Melanotic neuroectodermal tumor of infancy
Neural crest tumor occurring almost exclusively in jaws but does occur in extragnathic sites.
Most congenital - 1 year, anterior jaws, ↑ Mx.
Rapidly growing destructive radiolucency, often pigmented (melanin)
tumor cells produce VMA (Vanilymandelic Acid) in serum and urine.
Tx: Aggressive curettage 10-20% recur.
- Multiple Endocrine Neoplasia Type 3 (MEN 3) (2b)
95% of patients with mutation of RET gene, a proto-oncogene on chromosome 10.
50% - inherited as autosomal dominant
50% somatic mutation
a. Mucosal neuromas (predates other tumors)
b. Medullary carcinoma of thyroid
c. Pheochromocytoma of adrenal medulla
