1.  Who appreciates ART is NO LESS than who creates it 
Connective tissue neoplasms
 Connective tissue neoplasms:
 Clinically, most of the benign connective tissue tumors present as swellings which maybe
indistinguishable from hyperplastic lesions
Histologically, oral connective tissue tumors resemble their counterparts occurring at other sites in the body
 Classification of connective tissue neoplasms according to the tissue of origin:
1. Tumors of fibrous tissue
2. Tumors of adipose tissue
3. Tumors of vascular tissue
4. Tumors of peripheral nerves
5. Granular cell tumor
6. Tumors of muscles
7. Malignant lymphoma
 Tumors of fibrous tissue
 True benign neoplastic overgrowths of fibrous tissue (true fibroma) in the oral cavity are rare since
clinically and histologically they can't reliably be distinguished from hyperplasias
** The term fibroma has been used inappropriately to describe reactive lesions (such as fibrous epulis
and Fibroepithelial polyp) but to avoid confusion the term is best avoided except for specific entities
such as the peripheral odontogenic fibroma (which is a true benign tumor)
 Malignant tumors (fibrosarcoma) are also rare in the oral cavity and they have a relatively good
prognosis {5 year survival rate is 70%}
** Sarcoma = cancer of bone, cartilage, fat, muscles or blood vessels
** Sarcomas show the cytological malignant features of cellular and nuclear pleomorphism,
mitotic figures and Hyperchromatism
 Other lesions of fibrous tissue:
 Fibrous histiocytoma  There is disagreement amongst pathologists as to whether this benign soft
tissue lesion represents a true neoplasm, a developmental defect, or a reactive process. Cells in
here show fibroblastic and histiocytic differentiation. These tumors have unpredictable behavior
from locally aggressive to malignant. They are rare in the oral cavity and if they occur, they arise
on the buccal mucosa and vestibule
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2.  Who appreciates ART is NO LESS than who creates it 
 Nodular fasciitis  This benign soft tissue lesion represents a reactive non-neoplastic process
BUT the cause is still unknown. It is rapidly-growing but self-limiting and it may be mistaken
for a fibrosarcoma histologically. It is rare in the oral cavity
 Peripheral odontogenic fibroma  It is an uncommon gingival mass. It can be confused
with peripheral ossifying fibroma (fibrous epulis). In contrast to the peripheral ossifying
fibroma, the peripheral odontogenic fibroma is a rare lesion. It present clinically as slowly
growing, solid, firmly attached gingival mass sometimes arising between teeth and sometimes
displacing teeth. It consists of cellular fibrous connective tissue with non-neoplastic islands of
odontogenic epithelium
 Fibromatosis  This term refers to a group of non-neoplastic infiltrating fibrous proliferations
with a biologic behavior and microscopic appearance intermediate between those of true
fibromas and fibrosarcomas. They have certain characteristics in common, including: absence of
cytological & clinical malignant features, histological proliferation of well-
differentiated fibroblasts, an infiltrative growth pattern, and aggressive clinical behavior with
frequent local recurrence
** Aggressive fibromatosis: it is a rare slowly growing proliferation that is locally aggressive and
doesn't show any metastatic potential. It can damage nearby structures causing organ dysfunction.
Approximately 10% of individuals with Gardner's syndrome have such tumors. Histologically it
resembles low-grade fibrosarcomas but it is very locally aggressive and tends to recur even after
complete resection
** Hereditary gingival fibromatosis (e.g. gingival
overgrowth, gingival hyperplasia): it develops as a
slowly growing, non-neoplastic, localized or
generalized enlargement of gingiva that, in severe
cases, may cover the crowns of the teeth. Enlarged
gingiva may be normal in color or erythematous,
and consists of dense fibrous tissue that feels firm
on palpation. Gingival excess results in pocketing
and periodontal problems (due to difficulties in
daily oral hygiene). The overgrowth may also result
in functional and esthetic concerns, create
Diastema, impede or delay tooth eruption, impede
speech & mastication and can prevent normal closure of lips
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3.  Who appreciates ART is NO LESS than who creates it 
** Causes of localized fibrous overgrowths of the oral mucosa:
A. Hyperplastic lesions:
- Epulides (fibrous, vascular, giant cell)
- Pyogenic granuloma
- Fibroepithelial polyp
- Denture irritation hyperplasia
- Papillary hyperplasia of the palate
B. Neoplastic and neoplastic-like lesions:
- Peripheral odontogenic fibroma
- Fibrous histiocytoma
- Nodular fasciitis
- Fibromatosis
- Fibrosarcoma
 Tumors of adipose tissue:
 True benign neoplastic overgrowths of adipose tissue (lipoma) present clinically as soft yellowish
swelling, most commonly in the cheek and tongue
Histologically, lipoma is composed of circumscribed mass of mature adipose tissue supported with
stroma which varies in amount considerably
Lipoma can be histologically in the form of:
*Fibrolipoma  Lipoma and fibrous tissue stroma
*Angiolipoma  Lipoma and vascular tissue stroma
*Myxolipoma  Lipoma and connective tissue stroma
** A typical feature of lipoma is that it floats when it is dropped in the fixative solution (e.g. formalin)
** Some infants and young children are presented to the clinic with ulcerated tumor-like masses of fat
in the buccal mucosa which aren't actually tumors but traumatic herniation of the buccal pad of fat
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4.  Who appreciates ART is NO LESS than who creates it 
 Malignant tumors (liposarcoma) are uncommon,
most arise in cheeks, floor of the mouth or the base
of the tongue, they generally have good prognosis.
They show the cytological malignant features of
cellular and nuclear pleomorphism, mitotic figures
and Hyperchromatism
 Tumors of vascular tissue:
2. Hemangioma:
 It is a benign proliferation of endothelial cells
 It is a common lesion, generally accepted to be hamartomatous rather than true neoplasm
** Hamartoma = a benign focal malformation where there's abnormal and excessive formation
of normal tissues
 Hemangiomas commonly arise in the head and neck area, involving the mucosa, muscles, bone,
or major salivary gland (e.g. juvenile Hemangioma in parotid gland which is the commonest
salivary gland tumor occurring in infants and children)
 Most of them present at birth or arise during early childhood
 Clinical presentation:
- Dark red-purple in color
- Elevated lesion that is either smooth or globular (resembling
punch of grapes), soft or hard
- Varies in size
- Most of them arise on the lips, tongue, cheeks and palate
- Typically, they blanch on pressure (get white when
pressurized with a glass plate), however some lesions have
thrombosis or calcifications (which may be detected
radiographically) and get hard and so they don't blanch
- The lesion is usually asymptomatic and it is solitary BUT if
multiple then we might think of something systemic like
generalized angiomatous syndrome
- Some patients report recent increase in size but this may be a
result of hemorrhage,
thrombosis or inflammation
- The lesion may occur
intrabony and it presents as
radiolucent like cyst
radiographically that is filled
with blood histologically
 Histopathological presentation:
- According to the size of vascular spaces, hemangiomas may be classified into capillary,
cavernous or mixed type
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5.  Who appreciates ART is NO LESS than who creates it 
- Vascular spaces are lined by endothelium and filled with red blood cells
- Some lesions show evidence of thrombosis or calcification
** Capillary Hemangioma  a type of blood
vessel malformation that has relatively small blood-
filled spaces (increased number of blood vessels). It
is the most common variant of Hemangioma which
appears as a raised red area of flesh anywhere on
the body and usually starts at birth, increase in size
rapidly in the first few months, then decrease in
size with age & mostly resolve at the age of 9 years
** Cavernous Hemangioma  a type of blood
vessel malformation that has relatively large blood-
filled spaces (increased size of blood vessels). They
can arise virtually anywhere in the body and unlike
the capillary hemangiomas; they can be disfiguring
and do not tend to regress. They may also lead to
spontaneous or traumatic bleeding and ulcerations
** Cellular Hemangioma  some lesions
(particularly in infants) may be more solid, highly
cellular with little evidence of canalization, and thus
they are considered as immature stage of capillary
or cavernous Hemangioma, and it is difficult to
distinguish them from Pyogenic granuloma
(lobular capillary Hemangioma) clinically
3. Arteriovenous malformation:
 Abnormal connection between arteries and veins, bypassing the capillary system. This vascular
anomaly occurs in the central nervous system, but can appear in any other location
4. Sublingual varicosities:
 A condition where ranine veins get dilated and enlarged
 Varicosities starts at old age, its size increases with age and it doesn't tend to regress
5. Malignant vascular lesions:
 Kaposi sarcoma and angiosarcoma are rare but common in AIDS patients
6. Generalized angiomatous syndromes that may have oral lesions include:
 Sturge-weber syndrome:
- This is a congenital disorder in which the patient has:
1. Hemangioma of the face (port-wine stain) extending over one or more branches of
trigeminal nerve
2. Ipsilateral hemangiomas in the meninges over cerebral cortex
3. Contralateral convulsions affecting the limbs
** Hemangioma may also occur in the oral mucosa
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6.  Who appreciates ART is NO LESS than who creates it 
 Hereditary hemorrhagic telangiectasia:
- An autosomal disorder characterized by multiple knots
of dilated malformed and fragile capillaries in skin,
mucous membranes and may be the internal organs
- Frequent nose bleeding (epistaxis) is the commonest
presenting symptom
8. Lymphangioma:
 It is again generally accepted to be hamartomatous rather
than true neoplasm
 It is less common than Hemangioma
 It arises at birth or during early childhood
 It can occur anywhere in the oral cavity but are most
frequently seen on the tongue causing Macroglossia
 It is NOT red in color
 The surface of superficially located lesions shows numerous papillary projections or small
nodular masses
 If lesions get traumatized, it may undergo inflammation, calcification, or sudden increase in size
 Histopathological presentation:
 Consists of capillary or more common cavernous
endothelial lined spaces that contain lymph
 Superficially located lesions have the lymphatic spaces
extended close up to the overlying epithelium causing
it to bulge
 Cystic hygroma:
 It is a Lymphangiomatous malformation that occur early
in development of lymphatic system
 Lesions are detected at birth and present as large
fluctuant swelling often up to 10 cm in diameter
 They most frequently affect the head & neck region,
but may extend to involve the base of the tongue, the
floor of the mouth, and less commonly buccal mucosa
6/12

7.  Who appreciates ART is NO LESS than who creates it 
 Tumors of peripheral nerves:
1. Nerve sheath tumors:
1. Neurofibroma
- Solitary
- Multiple (neurofibromatosis)
2. Neurilemmoma (shwannoma)
2. Traumatic neuroma
3. Multiple mucosal neuroma
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1. Neurofibroma:
 It is a benign Schwann cell tumor arising from either
small cutaneous nerves (subcutaneous
Neurofibroma), or within larger nerves (Plexiform
Neurofibroma)
 It is a benign nerve sheath tumor in the peripheral
nervous system that arise either sporadically or in
association with neurofibromatosis type I (formerly
known as Von Recklinghausen’s disease)
 Neurofibromas arise from Schwann cells that
exhibit inactivation of the NF1 gene that codes for the
protein neurofibromin
 Neurofibroma is usually solitary BUT if it is associated
with neurofibromatosis type I then it is multiple
 Malignant transformation is a well-recognized
complication of multiple neurofibromas associated with
neurofibromatosis type I (5-15% of cases) but for the
solitary Neurofibroma it is rare
 Histopathological presentation:
 Neurofibroma shows considerable variation, but it
consists basically of Schwann cells and fibroblasts
with varying amount of collagen and mucoid tissue
 A few nerve fibers run through the lesion
 The lesion may be circumscribed or diffuse
 Plexiform neurofibromas:
- They are large cluster or mass of tumors arising
within or around the nerve trunk surrounded
by proliferation of Schwann cells & fibroblasts
- They are characteristic feature of
Neurofibromatosis type I
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8.  Who appreciates ART is NO LESS than who creates it 
- These lesions are difficult and sometimes impossible to routinely resect without causing
any significant damage to surrounding nerves and tissues
- About 10% of Plexiform neurofibromas undergo transformation into a malignant
peripheral nerve sheath tumor
 Neurofibromatosis type I (Von Recklinghausen’s disease):
 This genetic disease is either inherited (as familial condition or autosomal dominant) or
sporadic and occurs due to mutation in tumor suppressor gene (NF1)
 Clinical presentation:
- Multiple neurofibromas of cutaneous nerves
resulting in considerable disfigurement, the so-called
“Elephantiasis Neuromatosa”
- Intraorally: mucosal swellings (involving the
tongue or gingiva) and bone involvement (affecting
mental and inferior dental nerves in the mandible)
- “Café-au-lait” melanin pigmentation on the skin that
usually precede the neural
lesions
- Axillary freckling (axilla is a
non-sun exposed site!)
** Neurofibromas in here
transform into malignancy in
5-15% of cases
** Neurofibromas carry
increased incidence of malignant transformation upon surgical removal  thus NO
surgery should be done!
** If there's multiple giant cell lesions  suspect neurofibromatosis type I or primary
hyperparathyroidism
2. Neurilemmoma (Schwannoma):
 It is a benign Schwann cell tumor that is an encapsulated
 It is a benign nerve sheath tumor that is very homogeneous and consisting only of Schwann cells
 Nerve fibers don’t pass through the lesion BUT may be found over the capsule
 Within the lesion, spindle-shaped cells are often arranged in parallel bundles with palisaded nuclei
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9.  Who appreciates ART is NO LESS than who creates it 
3. Traumatic neuroma:
 It is a non-neoplastic disorganized mass consisting of
nerve fibers, Schwann cells and scar tissue that arise at the
end of a severed nerve
 It is an exaggerated nerve regeneration process which
usually presents as a small nodule
 Clinical presentation:
 Slowly growing
 Firm in consistency
 Fixed to surrounding structures
 Painful to palpation
** It is uncommon in the oral cavity although nerves
are frequently traumatized or severed following
extractions or minor surgery (usually occurs in relation
to large nerves, such as the ones related to the mental
foramen)
4. Multiple mucosal nueroma:
 Multiple neuromas of peripheral nerves in oral mucosa are a feature of multiple endocrine
neoplasia syndrome type III (also referred to as Type IIb) in which patients have:
 Multiple mucosal neuromas
- These neuromas are clinically and histologically similar to traumatic neuromas
- These neuromas may be the first presenting sign and may precede thyroid cancer
 Phaecromocytoma (tumor of adrenal gland cortex)
 Medullary thyroid carcinoma (the most important feature since this carcinoma is
aggressive and fatal!)
** The tumor is due to RET oncogene mutation, and those who have family history of the
syndrome may be tested for RET oncogene mutation, and if the result is positive this indicates
the need for prophylactic thyroidectomy
 Granular cell tumor:
 Was previously called {granular cell myoblastoma}, because it was thought to be of muscle origin.
BUT nowadays it is accepted to be of neural origin
 Etiology: it is a benign neoplasm probably due to proliferation of Schwann cells
 Clinical presentation:
 Slowly growing swelling
 Firm in consistency
 Fixed to the overlying mucosa and deep structures
 Painless
 Arises most commonly in the tongue
 Multiple tumors may occur
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10.  Who appreciates ART is NO LESS than who creates it 
 Histopathological presentation:
 Non encapsulated
 Composed of sheets and strands of large cells with
granular eosinophilic cytoplasm
** Granules represent Lysosomes, vacuoles, or residual
bodies
 The surface epithelium commonly shows may show
Psuedo-epitheliomatous hyperplasia that may be
mistaken with malignancy
 The presence of striated muscle fibers between the granular cells may suggest invasion but the
lesion is entirely benign
 Tumors of muscles:
 The following tumors have been reported in the oral cavity but they are rare:
 Of smooth muscles: Leiomyoma (benign), leiomyomatous hamartoma, leiomyosarcoma (malignant)
 Of skeletal muscles: Rhabdomyoma (benign) , rhabdomyosarcoma (malignant)
 Malignant lymphoma:
 It is a neoplastic proliferation of the cells of the lymphoreticular system
 The majority of malignant lymphomas in the head and neck arise in lymphoid tissue, the cervical lymph
nodes are most often affected followed by the lymphoid structures of Waldeyers' ring
 Lymphomas are usually classified into:
 Hodgkin’s lymphoma (characterized by Reed Sternberg cells)
 Non-Hodgkin’s lymphoma (B cell types, T and NK cell types)
A. Hodgkin’s lymphoma:
 Accounts for 30% of all malignant lymphomas
 Affects young age group
 Distribution: almost nodal and cervical lymph nodes are involved in about 75% of the cases
 Etiology: is unknown but genetic factors and viral infection (EBV) have been suggested
 Lesions are mostly part of disseminated malignancy
 Prognosis: depends on the clinical staging and histological grading and it decreases as the
lesion proceeds from lymphocyte-predominant to lymphocyte-depleted
 Overall survival rate is 50-70%
 Clinical presentation:
- Progressive painless enlargement of lymph nodes
 Histological presentation:
- Histological diagnosis depends on identification of
Reed- Sternberg cells which are regarded as the
neoplastic component
- Reed Sternberg cell is a large cell with either a
double or bilobed nucleus, the two nuclei lying
side by side to produce a “mirror image” effect
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11.  Who appreciates ART is NO LESS than who creates it 
- Histopathological types of Hodgkin’s lymphoma:
 Lymphocyte predominant  Few Reed-Sternberg cells and many lymphocytes 
good prognosis
 Mixed cellularity
 Nodular sclerosis
 Lymphocyte depletion  Numerous Reed-Sternberg cells and extensive fibrosis 
poor prognosis
B. Non-Hodgkin’s lymphoma:
 Much less common
 Lesions may remain solitary or they may disseminate
 Increased incidence reported in AIDS patients
 Divided into two main groups depending on the cells of origin:
1. B cell malignant lymphoma (the majority of malignant lymphoma cases are of this group)
2. T / NK cell lymphoma
 Non-Hodgkin’s lymphomas arising in lymphoid tissues other than lymph nodes (extra-nodal
lymphomas) are much less common than nodal tumors, but may arise in the oral soft tissues,
salivary glands, and jaw bones, e.g.:
– MALT lymphoma  have better prognosis than nodal lymphomas and lesions remain
localized for long periods and disseminate only late in the course of the disease
– Salivary gland associated lymphoma  this arise in the gland lymphoid tissue, or as a
result of malignant transformation in Sjögren Syndrome & myoepithelial Sialadenitis
– Bone
** Mucosal lesions present as soft, fleshy, often ulcerated swellings
** Burkitt's lymphoma is of particular interest since this type of malignant lymphoma
commonly presents as a jaw tumor
 Burkitt’s Lymphoma:
- It is a malignant lymphoma of B-cell type that is either endemic or sporadic, and in both
cases there is activation of an oncogene
** The Chromosomal abnormality in Burkitt’s lymphoma is reciprocal translocation of
chromosome 8 with chromosome 14, which may results in activation c-myc oncogene
** Without treatment, Burkitt's lymphoma is a rapidly fatal condition
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12.  Who appreciates ART is NO LESS than who creates it 
- Endemic cases:
 In Africa and affects mainly children between 2-14 yrs
 There is strong evidence that infection with the (EBV) is a causal factor and that
malaria is a cofactor
 The disease is usually multifocal, but a jaw tumor is the presenting symptom in over
half the cases
 In the jaws, lesions usually arise posteriorely and are more frequent in the maxilla
than the mandible, but more than one quadrant maybe involved
 Tumors are rapidly growing, and are often of massive size, producing gross facial
disfigurement
 In the maxilla, tumors extend into sinuses, nose, naso-pharynx and orbit
 Teeth in the area are loosened, displaced, and maybe exfoliated
- Sporadic cases:
 In non-African countries
 No (EBV) association
 Abdominal lesions predominate and jaws lesions are uncommon
- Histological presentation:
 A tumor of B-cell type
 Consists of small, darkly-staining
malignant lymphoid cells scattered amongst
pale-staining non-neoplastic macrophages
producing a "starry sky" pattern
 NK/T cell lymphoma:
- It is an uncommon condition
- The nasal NK/T cell lymphoma is a distinct entity and it may cause extensive
destruction of mid-facial structures and can extend into adjacent structures, including the
oral cavity
** Nasal NK/T cell lymphoma was reported
under a variety of terms in the past, including:
Angiocentric T cell lymphoma and lethal
midline granuloma
- It arises in nose/paranasal sinuses and presents
with nasal obstruction, epistaxis, and progresses
to extensive necrosis
- EBV is found in some neoplastic cells which
indicates that it may have a role in the
pathogenesis of the disease
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