Dson 6601 Connective Tissue Lesions In The Oral Cavity

Front 1

Fibrous Tissue Proliferations

Back 1

A focal connective tissue proliferation confined to the gingiva is generally called an epulis. These lesions
are reactive instead of neoplastic and are often associated with injury.

Front 2

Irritation Fibroma, (traumatic fibroma, focal fibrous hyperplasia)

Back 2

The irritation fibroma is the most common of all hyperplastic growths in the oral cavity. It generally results
from a long-term injury or irritation and represents, what in reality is no more than a form of scar. Irritation
fibromas are not true neoplasms, but simply exuberant hyperproliferations of collagen due to injury.
The most common site for the irritation fibroma, or focal fibrous hyperplasia is in the cheek. Other sites
include the tongue or gingiva. Ulceration can occur so that the lesions can become problematic and painful.
Low-grade chronic inflammation of these lesions is
The histopathogy of the irritation fibroma shows squamous epithelium overlying hyperplastic collagen with
a proliferation of endothelial cells, vascular channels, and fibroblasts. Some fibromas occasionally contain
giant cells and are termed giant cell fibromas. The treatment for irritation fibroma or focal fibrous
hyperplasia is surgical excision and the lesions rarely occur.

Front 3

Peripheral Ossifying Fibroma

Back 3

The peripheral ossifying fibroma generally presents as a nodule affecting the gingiva. It is a form of
reactive hyperplasia that frequently contains bone. It is generally thought to be a periodontal ligament or a
periosteal origin and they are related to long-term irritation in most instances. Women are affected more
often then men, usually in the third or fourth decades. Since the lesion arises from the periodontal ligament
structures or periosteum it is thought to have a somewhat more aggressive behavior than the typical
irritation fibroma.
Histologically, the POF is quite different as well, although, like the fibroma, the lesion is nodular and has a
connective tissue base, reactive bone fragments are prominent throughout the supporting collagen.
Epithelial rests of odontogenic origin may also be seen.
The treatment for the peripheral ossifying fibroma is surgical excision that has to include some portion of
the periodontal ligament. This lesion has a much higher recurrence than the typical irritation fibroma. There
are instances in which it is aggressive enough to extend into the periodontal ligament space, destroy bone
and necessitate extensive surgery.

Front 4

Peripheral Giant Cell Granuloma

Back 4

Like the previous two lesions, the peripheral giant cell granuloma is an extraosseous nodule that most often
affects the gingiva. Histologically, two cell types are usually seen. Connective tissue cells and vascular
cells. The connective tissue cells or fibroblasts and the endothelial cells often coalesce into multinucleated
giant cell forms, and they may surround sinusoidal spaces. These giant cells are the type that can also be
seen in the brown tumor of hyperparathyroidism, cherubism, and the central giant cell granuloma of bone.
The peripheral giant cell granuloma can be found in all age groups, but there is a peak incidence 25-30
years. It occurs in the anterior and posterior mandible, but it is more often found in the anterior molar
region. The lesions generally present as soft tissue, reddish brown, dome shaped swellings, which may be
ulcerated. Sometimes they can involve and encircle more than one tooth and they are aggressive enough to
invade the periodontal ligament, loosening teeth. Often a radiograph will show saucerized defects
surrounding the soft tissue excrescence.
Histologically, the lesion is composed of multinucleated giant cells ramifying throughout a well-
vascularized connective tissue stroma. Sometimes the tumors are laden with hemosiderin blood breakdown
products.
The treatment for the peripheral giant cell granuloma is typically surgical excision, although there has been
recent information in the literature suggesting that steroid injections may be helpful in reducing the size of
lesions. Recurrence rate is in the 12% range and occasionally the lesions recur necessitating extraction of
teeth.

Front 5

Pyogenic Granuloma

Back 5

A third lesion that should be considered here, not because it is a connective tissue lesion, but from a
differential diagnostic standpoint, is the pyogenic granuloma. The pyogenic granuloma may look clinically
identical to a peripheral giant cell granuloma or a peripheral ossifying fibroma and should be included in
the differential diagnosis when lesions are evaluated clinically. The pyogenic granuloma will be discussed
more fully under vascular lesions since it is largely a lesion of vascular tissue.

Front 6

Inflammatory Fibrous Hyperplasia

Back 6

Inflammatory fibrous hyperplasia is an over-exuberant proliferation of fibrous connective tissue associated
with a diffuse chronic inflammatory response, most often due to long-term injury. The most common cause
for the inflammatory fibrous hyperplasia is ill-fitting dentures. These lesions generally occur along denture
flanges and have been termed epulis fissuratum.
Clinically, inflammatory fibrous hyperplasia can involve maxillary or mandibular ridges and present as
flabby, soft, freely movable tissue.
Histologically, the lesion is composed of stratified squamous epithelium with marked acanthotic rete ridges
overlying a fibrous connective tissue stroma that is chronically inflamed. The lesions are usually treated by
surgical excision if they are large and extensive. Occasionally, if they are small, they can be treated by
rebasing or relining the denture.

Front 7

Inflammatory Papillary Hyperplasia

Back 7

Inflammatory papillary hyperplasia is a lesion that is also related to redundant proliferation of tissue, most
often the presenting as small papillary nodules affecting the palate. The most common cause once again is
an ill-fitting denture. The response to irritation is most often a palatal corrugate papillary appearing growth
that is cobblestone or mushroom-like. The lesions are generally non-tender and red rather than white. They
can become white after long-term irritation and hyperkeratosis. Differential diagnostic considerations in a
long-term smoker who may present with papillary lesions of papillary hyperplasia include verrucous
carcinoma a form of cancer.
Histopathologically, papillary hyperplasia is composed of polypoid epithelium with finger-like projections
and a chronically inflamed connective tissue stroma. Treatment is usually wide surgical excision,
electrocautery, or laser surgery. This process has no malignant predisposition.

Front 8

Hyperplastic Gingivitis

Back 8

Hyperplastic gingivitis, also known as focal or generalized fibrous hyperplasia of the gingiva most often
occurs during puberty and pregnancy, in which case it is termed pregnancy or puberty gingivitis. It is in
reality no more than an excessive fibrous hyperplasia with inflammation.
Histologically, the lesion is composed of keratinizing squamous epithelium overlying chronically inflamed
fibrous connective tissue with marked vascularity.
The treatment for the disorder is dental prophylaxis, scaling or polishing. The lesions generally dissipate
after therapy. In instances of pregnancy or puberty the lesions will persist until the patient is brought to
term, or puberty is completed. In some instances surgical recontouring of the gingiva may be necessary to
treat the disorder.

Front 9

Hereditary Gingival Fibromatosis

Back 9

Hereditary gingival fibromatosis is generalized hyperplasia of the gingiva, which is a disorder associated
with not simply hyperplastic gingiva, but also craniofacial developmental anomalies, epilepsy, mental
retardation and hypertrichosis. The exact mechanism of the disease is not understood but it appears to be
restricted to fibroblast. There are two modes of inheritance, autosomal dominant and autosomal recessive.
In this disorder the gingiva becomes markedly enlarged to the point that it can actually cover the incisal or
occlusal surfaces of the teeth.
Facial anomalies, such as hypertelorism or a widening of the spaces between the eyes can be noted. In most
instances the gingival enlargement begins at puberty and shows progressive proliferation. Eruption of teeth
is most often normal.
Histologically, the tissue is composed of keratinized squamous epithelium overlying relatively dense
collagen with some proliferating fibroblasts and inflammation. Treatment is usually gingivectomy.
Sometimes the lesions are recurrent and multiple surgical procedures have to be employed. Oral hygiene
improvement does not seem to influence the degree of hyperplasia in these patients.

Front 10

Drug-Induced Gingival Hyperplasia

Back 10

Drug induced gingival hyperplasia is a form of fibrous hyperplasia in patients who are on long-term doses
of cyclosporine and nifedipine. It has also been referred to in the past as Dilantin hyperplasia, but this term
is not appropriate since the hyperplasia can be related to a host of other drugs, including the cyclosporines
that are used in transplantation, and Nifedipine, a calcium channel blocker used in cardiac patients. The
gingival enlargement due to these drugs can cause swelling in the interdental papilla area. Generally it
becomes evident within the first year of administration of the drug. Occasionally one sees pseudopocketing
around the crowns of teeth.
Histologically, the lesions show hyperplastic response in which there is keratinized squamous epithelium,
with elongated rete ridges, dense mature collagen, and widely spaced spindle shaped fibroblasts.
Inflammation is variable.
The treatment for this disorder is usually localized gingivectomy or gingivoplasty. Fibrous changes slowly
recur if the drugs are continued. The hyperplasia may be accelerated by the accumulation of plaque and
calculi, so oral hygiene maintenance is imperative for these patients.

Front 11

Indeterminate Proliferations

Back 11

There are a group of indeterminate fibrous proliferations that occur in the oral cavity that are thought to be
somewhere between reactive growths, such as a fibroma, and malignant growths, such as fibrosarcoma.
These disorders result in proliferative fibrous growths that can be quite destructive, but are not malignant.
Two of these disorders will be discussed here.

Front 12

Desmoplastic Fibroma

Back 12

The desmoplastic fibroma is a benign fibrous infiltrative proliferation resulting in very dense mature
collagen, most often found in the mandible of young patients. The lesion can be quite aggressive and may
necessitate mandibular resection. The recurrence rate is in the 25% range.

Front 13

Nodular Fasciitis

Back 13

Nodular fasciitis has also been termed pseudosarcomatous fasciitis because microscopically it looks like a
sarcoma or malignancy. This lesion most often occurs as a spindle cell proliferation affecting the oral
mucosa and has a local recurrence rate in the 20% range.

Front 14

Benign Fibrous Histiocytoma

Back 14

Benign fibrous histiocytoma is a fibrous proliferation that also exhibits histiocytic proliferation. The lesions
that occur can be in soft tissue or bone and they present as nodular swellings or radiolucencies.
Microscopically, the lesions often have, what is known as, a storiform pattern with a cartwheel or pinwheel
accumulation of fibrohistiocytic cells. The lesions are treated by wide excision and 20% recurrence within
the first two years is common.

Front 15

Fibrosarcoma

Back 15

The final fibrous connective tissue growth of importance to us here is the fibrosarcoma, which is a
malignant neoplasm of fibroblastic cells. Considering the spectrum of lesions we have covered, from the
benign fibroma, through the intermediate lesions, such as benign fibrous histiocytoma and nodular fasciitis,
the fibrosarcoma is the aggressive end of the spectrum. Fibroblasts become malignant in this particular
tumor, resulting in a life-threatening disorder. It may affect the soft tissue more often than bone. They grow
rapidly and may be associated with pain, paresthesia, or bleeding. Root resorption and tooth displacement
are common when they involve bone and there may be marked expansion of the cortex. Fibrosarcoma is a
highly cellular lesion, histopathologically, and is composed of a proliferation of atypical appearing
fibroblasts arranged in what is known as a herringbone pattern. Histologically, mitotic activity is prominent
and the cells often have a foamy cytoplasm.
Fibrosarcomas are treated by aggressive therapy, which may include surgery, radiation therapy and/or
chemotherapy. The prognosis is always poor and even with radical wide excision, which is the treatment
of choice; the lesions are most often lethal within a 5-7 year period.

Front 16

Neural Tissue Tumors

Back 16

Nerve tumors are relatively common in the oral cavity and generally arise from a reactive or neoplastic
proliferation of the cells that surround the nerve axis cylinder. When there is injury to this site, a host of
nerve lesions can occur, from benign processes, such as traumatic or amputation neuromas through
malignant processes, such as neuro fibrosarcoma. Nerve proliferation can be classified as hyperplasia,
hamartomas, benign neoplasms and malignant neoplasms.

Front 17

Hyperplasia: Traumatic Neuroma

Back 17

This lesion is a painful, nodular growth, resulting from a proliferation of nerve and fibrous connective
tissue from the nerve sheath that results because of a failed attempt of the nerve fibers to unite, after they
have been severed. The traumatic neuroma is also often referred to as an amputation neuroma. When two
nerve segments are displaced an intermediate segment of axis cylinder elongation with accompanying
nerve sheath results that includes a proliferation of Schwann cells and perineural fibroblasts. This
incomplete attempt to reunify the segment results in a fibrous union that is most often painful. The most
common site for a traumatic neuroma is along the distribution of the mental nerve and most often the
patient will give a history of trauma or laceration of the nerve.
Histologically, the traumatic neuroma represents a form of hyperplasia, so that microscopically there is a
proliferation of axis cylinders, Schwann cells and enveloping perineurium. The nerve bundles are arranged
in an oval, elongated, sort of torturous pattern when seen microscopically.
The treatment for the traumatic neuroma is usually surgical excision and recurrence is possible, but after
complete excision, uncommon.

Front 18

Multiple Endocrine Neoplasia Syndrome

Back 18

This syndrome, which may often be seen abbreviated as MEN syndrome is an autosomal dominant
condition affecting the parathyroid glands, pancreas, thyroid, and adrenal glands. One variant of the
syndrome, which is known as MEN-IIB syndrome is associated with multiple neuromas of the mucous
membrane surfaces. Patients with this form of the syndrome will exhibit have multiple mucosal neuromas
most often on the tongue. The lesions present as small nodular excrescencies.
Histologically, they appear similar to the traumatic neuroma. Patients with this syndrome often develop
malignant neoplasms, including medullary carcinoma of the thyroid gland and pheochromocytoma of the
adrenal medulla. Often the initial diagnosis of the syndrome is related to identification of mucosal
neuromas on the tongue.
The treatment for the oral component of the disorder is to remove the neuromas in the oral cavity

Front 19

Neurilemoma

Back 19

The neurilemoma is a benign well-demarcated neoplastic process of nerve sheath or Schwann cell origin.
Clinically the lesions can present as soft tissue nodular swellings or as bony lesions within the mandible or
maxilla. The central bony lesions are quite rare. Neurilemomas can also affect the acoustic nerve, in which
they are called acoustic neuromas. Most often they are not associated with pain and present as nodular firm
raised swellings.
Histologically, the neurilemoma is made up of two cell types Antoni A type tissue, which presents as
parallel rows of palisading nuclei and Antoni B type tissue, which is composed of oval nuclei with a dense
vacuolated surrounding cytoplasm. These two cell types, arranged in a palisading pattern, are diagnostic of
the tumor. There are multiple variations of this tumor, including the so-called palisaded neuroma, which
occurs on the hard palate.
The treatment for the neurilemoma is surgical excision and the recurrence rate is generally in the 10%
range.

Front 20

Neurofibroma

Back 20

The neurofibroma is a benign nerve neoplasm that is composed of a proliferation of perineural fibroblasts
arranged in a random fashion and set in a myxoid background. A variation of neurofibroma is known as
multiple neurofibromatosis or von Recklinghausen’s disease, in which there are multiple neurofibromas of
the skin and aberrant skin pigmentation. These lesions can undergo malignant transformation, but rarely.
The neurofibroma generally presents as a nodular fibrous swelling affecting the buccal mucosa or lips,
although it can occur within bone. Most lesions are identified in adults rather than children and they show
no sex predilection. They may be firm or quite soft to palpation. With neurofibromatosis the patients may
have up to 100 on their skin at any one time.
Often when the lesions present in the oral cavity they present as small nodular excrescencies or pendulous
swellings. Neurofibromatosis, whether multiple or singular are often associate with brown pigmentations
on the skin called café au lait spots. These macular pigmentations are focal accumulations of melanin and
often part of the von Recklinghausen’s syndrome. Repeated surgical excision of multiple neurofibromas
may predispose the patient to malignant transformation into neurogenic sarcoma. It is thought that
somewhere between 3-6% of all patients with neurofibromatosis will manifest malignant nerve sheath
transformation.
Occasionally neurofibromas can occur within bone, in which case they are referred to as central
neurofibromas. Radiographically they are well-circumscribed swellings found within the bony
compartment. They can be unilocular or multilocular and rarely cause penetration of the cortex.
Histologically, neurofibromas are composed of a haphazard accumulation of spindle shaped cells that
stream throughout a collageneous product.
The treatment for these oral tumors is usually wide, local excision and recurrence is common. Multiple
recurrences may be associated with malignant transformation.

Front 21

Granular Cell Tumor (Granular Cell Myoblastoma)

Back 21

The granular cell tumor is a submucosal mass most often affecting the tongue. It is characterized by a non-
painful swelling, generally on the ventral surface of the tongue. The lesion is rare in other sites. It
sometimes has an orange or yellow tinge to it when it is seen clinically. The lesion is thought to arise from
Schwann cells and therefore it is often classified as a nerve tumor, although in the past it has been called a
granular cell myoblastoma that suggests a muscle origin. Men are more commonly affected. Occasionally
multiple granular cell tumors can be seen.
The histopathology of this tumor is quite unique, consisting of keratinizing squamous epithelium overlying
collagen that is infiltrated with an abundance of foamy appearing granular cells. One common feature of
this tumor is that the overlying epithelium undergoes marked pseudoepitheliomatous hyperplasia. This
hyperplastic response is often misconstrued as malignancy and in some cases an erroneous diagnosis of
squamous cell carcinoma has been made. The granular cells in this tumor are thought to emanate from
nerve sheath cells, and immunohistochemical stains most often support nerve sheath origin.
The treatment for the granular cell tumor is simple local excision and recurrences are exceedingly rare.

Front 22

Congenital Gingival Granular Cell Tumor

Back 22

The congenital granular cell tumor most often occurs on the gingiva and has been referred to in the past a
congenital epulis of the newborn. It usually occurs in newborns and affects the anterior maxilla or mandible
as a nodular swelling. It is more common in females than males and presents as a pedunculated mass
emanating from the ridge. It may grow up to many centimeters in diameter.
The congenital epulis is of nerve sheath origin and histopathologically consists of large granular cells
identical to those seen in a granular cell tumor. However, with this tumor there is no evidence of
pseudoepitheliomatous hyperplasia and the lesions are negative for S-100 protein, whereas in the granular
cell tumor they are positive.
The treatment for this lesion is surgical excision to the base of the lesion and recurrences are very rare.

Front 23

Neuroectodermal Tumor of Infancy

Back 23

This lesion, which was once thought to be a tumor of odontogenic origin, is actually a pigmented neoplasm
that most often affects the anterior maxilla and arises from cells derived from the primitive neural crest.
The lesion most often presents as a pigmented swellings of the maxilla, usually in patients before six
months of age. The surfaces of the lesions may be brown, black or otherwise pigmented. The tumor is
occasionally seen in other anatomic sites in the body, including the shoulder, scapula, mediastinum and
perineum.
The histopathology of the lesion is unique in that two cell types are seen. Large dark granular cells arranged
in an alveolar pattern in the connective tissue, and smaller cells containing pigment which are also
distributed throughout the connective tissue stroma. The tumor is generally treated by surgical excision and
curettage, and recurrence is rare.

Front 24

Malignant Neoplasms of Nerve Origin

Back 24

Malignant neoplasms of nerve origin are generally referred to as neurogenic sarcomas and they arise from
perineural fibroblasts or Schwann cells usually from some associated nerve trunk. They are rare in the oral
cavity and are highly cellular tumors. The treatment for neurogenic sarcoma is generally wide surgical
excision, but hematogenous metastases occur in at least 50% of the cases. Even with aggressive surgery,
most patients succumb to the disease process.

Front 25

Muscle Tumors

Back 25

Muscle tumors can be benign or malignant. Benign lesions that arise from striated muscle are termed
rhabdomyomas. Those that are benign and of smooth muscle origin are termed leiomyomas. The malignant
variants of these are rhabdomyosarcoma, (malignant smooth striated muscle tumor) and leiomyosarcoma
(malignant smooth muscle tumor).

Front 26

Leiomyoma

Back 26

The leiomyoma is a benign neoplasm of smooth muscle origin that is rare within the oral cavity and usually
arises from the smooth muscles surrounding blood vessels. The lesions are usually firm, movable and
present as submucosal nodules. Differentiation of leiomyoma from neurofibroma is often difficult
microscopically. These lesions are usually treated by local excision.

Front 27

Rhabdomyosarcoma

Back 27

The rhabdomyosarcoma is a malignant neoplasm of striated muscle that can occur in three cell types,
embryonal, alveolar, and pleomorphic. All forms of the tumor have an exceedingly poor prognosis.
Although the rhabdomyosarcoma is a frequently a lethal neoplasm, improved surgery, radiation therapy and
multiple drug chemotherapy have made the prognosis for this disease process better in the past ten years.

Front 28

Adipose Tissue Tumors

Back 28

The most common tumors of adipose tissue are the lipoma, which is a benign fat cell tumor. The
liposarcoma is its malignant counterpart. The latter is an exceedingly rare fat cell tumor

Front 29

Lipoma

Back 29

The lipoma usually presents in the oral cavity as a soft yellowish swelling. The lesion has no sex
predilection and most lipomas appear in the superficial connective tissue of the cheek or floor of the mouth.
Occasionally herniated buccal fat pads can be misdiagnosed as lipomas. When multiple fat cell tumors in
the oral cavity occur the disorder is knows as multiple lipoblastomatosis.
Histopathology, the lesion is composed of univacuolated fat cells set in a connective tissue stroma. The
treatment is generally surgical excision or enucleation and recurrence is rare.

Front 30

Liposarcoma

Back 30

Liposarcoma is the malignant counterpart of lipoma. It is exceedingly rare in the oral cavity. When
liposarcomas occur they usually present as multilobular lesions in the sublingual or buccal mucosal regions.
The histopathology of the liposarcoma demonstrates cellular pleomorphism as opposed to the benign fat
cell appearance of lipoma. The treatment is usually radical excision and the lesions are usually lethal in the
long run.

Front 31

Vascular Tissue Tumors

Back 31

The two most significant tumors affecting the vascular compartment of the body are hemangiomas and
lymphangiomas. Hemangiomas arise directly from endothelial cells of blood vessels while lymphangiomas
arise from the lining endothelial cells of lymphatic vessels. The lesions most often have a red, purple, or
blue appearance clinically. Lesions can occur in soft tissue or in bone. In soft tissue they tend to often have
a bumpy or corrugated appearance. When they occur in the bone, the mandible is the favorite site. When
they occur in the oral cavity, the tongue is the favorite site. One characteristic feature of both lesions is that
they appear to grow from within the body of the tissue as opposed to being “stuck” on the tongue as with
the fibroma or pyogenic granuloma.

Front 32

Pyogenic Granuloma

Back 32

The pyogenic granuloma is an exceedingly common lesion of the oral mucous membranes that is a
reparative hyperplasia. It is a fast growing reactive benign proliferation of endothelial cells, usually found
on the gingiva and frequently related to excessive hormonal expression during pregnancy. The lesions are
generally not, as the name would apply, a direct reaction to microorganisms but instead growths resulting
from chronic irritation. The lesions generally appear as soft tissue nodules affecting the gingiva, and they
frequently ulcerated. When the lesions are seen during pregnancy, they are generally referred to as
pregnancy tumors. They can range in size from a few millimeters up to 3-4 cm in diameter and can reach a
size that is quite dramatic in less than one week. The lesions also can arise from extraction sites or from
areas where the oral cavity is injured, from a bite for instance.
This histopathology of pyogenic granuloma is quite dramatic in that the vascular component of the lesion is
the dominant histologic feature. Microscopically, dilated vascular channels, endothelial cells, granulation
tissue, and hemorrhage are prominent. The lesion can be confused with Kaposi sarcoma because of the
marked vascularity. Kaposi sarcoma is the malignant vascular disorder seen in association with AIDS.
The treatment for pyogenic granuloma is usually excision to the base of the lesion. Recurrence is quite
common in the 15-20% range.

Front 33

Hemangioma

Back 33

The hemangioma is a proliferation of capillary or cavernous spaces affecting the collagenous tissues of the
body, most frequently seen in children. As previous noted, it is usually identified in the oral cavity in the
tongue. Occasionally lesions consistent with a hemangioma clinically turn out to be hamartomatous lesions
or lesions over proliferation of tissue that is normally present in an anatomic site, and not a true neoplasm.

Front 34

Variations of hemangioma

Back 34

The oral varix is no more than a venous dilation affecting the oral cavity that becomes hyperplastic
resulting in a purple swelling or spot.
There are certain syndromes that are associated with hemangiomas in the oral cavity. One significant
disorder is Sturge-Weber syndrome or encephalotrigeminal angiomatosis. This disorder is characterized by
the so-called unilateral port-wine stain on the face and can be a significant problem therapeutically
Arteriovenous (AV) malformations do occur in the head and neck region and represent malformations in
which there is a confluence of both arterial and venous components. The most common site in the head and
neck region is the mandible.
The histopathology of the hemangioma can either be capillary or cavernous. Capillary hemangiomas are
composed histologically of small vascular channels while cavernous hemangiomas are composed of large
vascular spaces or channels. Both types are all lined by endothelial cells and usually filled with red cell
aggregates.
The typical hemangioma usually requires treatment, but the AV malformation is rarely treated since
surgical intervention can result in uncontrolled hemorrhage and death. The lesions are usually diagnosed
using studies that include Doppler angiography or contrast time-lapsed angiography.
Treatment can include surgery, induced immobilization of the feeder vessels, or cryosurgery. All of these
lesions are problematic because they have recurrence rates in the 15-20% range.

Front 35

Lymphangioma

Back 35

Lymphangioma is a benign proliferation of vessels that are of lymphatic origin. They occur superficially
within the oral cavity and can also affect the neck. Lesions that affect the neck are generally seen in young
children before the age of two, in which case they are called cystic hygroma.
The histopathology of lymphangioma is somewhat different from that of a hemangioma since the vascular
spaces often hug the tissue epithelial interface as large dilated spaces filled with lymph material or
proteinaceous coagulum. With hemangiomas the endothelial cell proliferation and vascular spaces tend to
be deeper in the connective tissue.
The treatment of lymphangiomas is to usually wait and watch approach. Most lesions revert spontaneous
during or after puberty. Occasionally that doesn’t happen and surgical intervention with cryosurgery or
laser surgery has to be entertained.

Front 36

Angiosarcoma and Kaposi Sarcoma

Back 36

The angiosarcoma is the malignant counterpart of a hemangioma. The lesions are rapidly growing and lined
by endothelial cells. They are usually seen in young patients and have a very poor prognosis. The most
commonly encountered angiosarcoma of the oral cavity, Kaposi sarcoma, is associated with AIDS. Kaposi
sarcoma as opposed to angiosarcoma is generally multifocal in the oral cavity. The lesions are rapidly
growing, aggressive, and metastasize readily. Kaposi sarcoma in the absence of HIV infection is relatively
rare, but it can be seen as a solitary skin lesion, usually in older men, and most often on the legs. Kaposi
sarcoma in the oral cavity usually presents as a flat macular purple plaque, or as an elevated nodular purple
lesion. The lesions are quite vascular and most commonly affect the palate, followed by the gingiva.
The histopathology of Kaposi sarcoma differs from that of the typical hemangioma or pyogenic granuloma
in that the slit-like vascular channels and spaces, which are lined by endothelial cells, become exceedingly
hyperplastic. The endothelial cells began to become arranged back-to-back and they take on a pleomorphic
appearance. The tumor has altered nuclear cytoplasmic ratios, lack of mitotic activity and cytologic atypia.
The treatment for Kaposi sarcoma in HIV positive individuals, who have multicentric or multifocal disease,
involves either injection with sclerosing agents such as Vincristine or Vinblastine or low dose radiation
therapy. The lesions will shrink but only for a limited period of time. After six months to one year, they
recur. In most cases the patients die from the complications of the disease, although protease inhibitor
therapy is resulting in marked improvement.

Front 37

Osseous and Cartilaginous Tissues

Back 37

Bone and cartilaginous tumors of the jaw will be discussed under the heading of fibro-osseous lesions in
the second semester of this course. There are, however, a few lesions that need to be discussed at this point
since they are connective tissue lesions that best fit in the classification here.

Front 38

Soft Tissue Osteoma

Back 38

The osteoma of soft tissue usually presents as a soft tissue growth affecting submucosal tissues in the oral
cavity. These osteomas are often associated with the syndrome known as Gardner syndrome. This
syndrome includes supernumerary impacted teeth, facial bone osteomas, cutaneous nodules or fibroids, and
polyps of the intestine. These polyps have a precancerous potential. The calcified lesions that occur in the
oral cavity may present as diffuse multifocal osteomas of the jaws. The subcutaneous nodules of the skin
are actually hamartomas. The polyps of the colon can undergo malignant transformation into
adenocarcinoma about 15% of the time.
Histologically, osteomas are composed of compact laminar bone. The treatment for the osteomas is
surgical excision if they impair function. Otherwise they are left to grow in a self-limiting fashion

Front 39

Osseous and Cartilaginous Choristoma

Back 39

The osseous and cartilaginous choristomas arise that as firm soft tissue nodules in the oral cavity, with a
central nidus of calcified metaplasia. Histologically, they consist of soft tissue surrounding bone or
cartilage, which can be in any phase of development, from immature woven bone or cartilage through
mature lamella bone. The treatment is surgical excision.

Front 40

Myositis Ossificans

Back 40

Myositis ossificans is a disorder in which trauma precipitates osseous metaplasia within muscle resulting in
a calcified product within the muscular compartment. The most commonly affected regions in the oral
cavity are the masseter and pterygoid muscles.
Histologically, the lesion consists of proliferating fibrous connective tissue inside muscle with thin delicate
aggregates of associated bone. The treatment is usually surgical excision to remove the calcified mass. The
lesion has no malignant potential.
Malignant bone tumors, including osteosarcoma, will be discussed with fibro-osseous lesions in Semester
II.