Hemangiomas are tumorlike malformations composed of seemingly disorganized masses of endothelium-lined vessels that are filled with blood and connected to the main blood vascular system.They have been described in almost all locations in and about the oral cavity and face and may involve deep structures such as the jaw and facial bones, salivary glands, muscles,and the temporomandibular joint, as well as the surface mucosa and skin. They may occur as isolated lesions in the oral cavity (Figure 7-10), as multiple lesions affecting different parts of the body, and in association with other developmental anomalies in the various angiomatous syndromes described below. They range from simple red patches (nevus flammeus, port-wine stain)(Figure 7-11, A) or birthmarks (nongeneti-
cally transmitted embryologic mishaps),which do not raise the mucosal or skin surface, to large fungating masses, which bury teeth and cause serious deformity and disfiguration. Small lesions may be clinically indistinguishable from pyogenic granulomas and superficial venous varicosities. Both cavernous and capillary types have been described; the former consists of relatively large blood-filled lakes, and the latter consists of masses of proliferating vessels of capillary dimension. In both cases, there is a simple endothelial lining to the vascular channels and little connective-tissue stroma. Such lesions characteristically bleed profusely when traumatized.
Many hemangiomas are evident at birth, and they frequently increase in size with general bodily growth. The filling of previously empty vascular channels also accounts for an increase in the size of these lesions, and such changes sometimes occur very rapidly following trauma. While such growth is to be distinguished from neoplasia, this distinction may not be easy to make clinically, and the clinician will quite reasonably sometimes be concerned that what is assumed to be a hamartomatous lesion may be developing a neoplastic tendency. Diascopy is the technique of applying pressure to a suspected vascular lesion to visualize the evacuation of coloration, a finding that supports the fact that patent blood-filled spaces constitute the lesion. If compression fails to evacuate the pigmentation, the lesion could be extravasated blood or some other type of intrinsic or extrinsic pigment that has been deposited in the tissues (see Chapter 6, “Pigmented Lesions of the Oral Mucosa”).
When located on the surface of the skin or oral mucous membrane, hemangiomas are usually readily identified. Large lesions are warm and may even be pulsatile if associated with a large vessel. Hemangiomas of the tongue (see Figure 7-10) and gingiva are often covered by unusually rugose epithelium. Differentiation should be made from vascular inflammatory hyperplasias, sublingual varicosities (varicosities of the superficial veins on the ventral surface of the tongue that are common after 50 years of age), pigmented nevi, telangiectasias of various etiologies, and hematomas. Centrally located heman-
giomasmust be distinguished from the many osteolytic tumors and cystlike lesions that affect the jaws, as well as from both congenital and acquired arteriovenous aneurysms of the jaw. Care should be taken in excising or performing biopsies on hemangiomas, partly because of their tendency to uncontrolled hemorrhage and partly because of the difficulty of knowing the extent of the lesion, only a small part of which may be evident in the mouth.
Gingival hemangiomas may connect with similar lesions in the jawbone, and radiographic examination of the bone may not always reveal an abnormality of the trabecular architecture. Most such lesions are observed clinically as multilocular radiolucencies; therefore, when this radiographic pattern is observed, the lesion should be aspirated. Some central hemangiomas of bone represent arteriovenous malformations, and the blood coursing through them is under arterial pressure. A bright red aspirate is highly suggestive of central hemangioma and requires that imaging studies be instituted to confirm the clinical impression. Computed tomography, Doppler and conventional ultrasonography,radionuclide-labeled red cell scintigraphic scanning,and superselective microangio graphyare used to define the extent of bony hemangiomas, and radiographic examination of the affected tissues may reveal not only bony defects but also phleboliths in the cheek that mark the location of abnormal vessels. Hemorrhage from centrally located hemangiomas of the jaw is especially difficult to control, and surgery on hemangiomas should be attempted only when provision has been made beforehand to control any untoward hemorrhage that may occur (typed and crossmatched blood, splints, and means of tying off branches of the external carotid artery). In general, electrocoagulation and cryosurgery cause less postoperative hemorrhage than incision with a scalpel causes.
The treatment of hemangiomascontinues to be a difficult problem fraught with the danger of uncontrollable hemorrhage. Conventional surgical techniques have been largely replaced by cryosurgeryand laser surgery,often preceded by the injection of sclerosing solutions.Also, intravascular embolization with plastic spheres is now a commonly used and successful approach. Although radiation can be used to sclerose these lesions,the risk of inducing neoplastic and other degenerative changeslater in life is very high, and its use is now generally contraindicated, particularly in children. Many of the reported cases of malignant change in hemangiomas undoubtedly are the results of radiation treatment. Intralesional injection of corticosteroids is sometimes a successful alternative to surgery for hemangiomas in infants.
When located on the surface of the skin or oral mucous membrane, hemangiomas are usually readily identified. Large lesions are warm and may even be pulsatile if associated with a large vessel. Hemangiomas of the tongue (see Figure 7-10) and gingiva are often covered by unusually rugose epithelium. Differentiation should be made from vascular inflammatory hyperplasias, sublingual varicosities (varicosities of the superficial veins on the ventral surface of the tongue that are common after 50 years of age), pigmented nevi, telangiectasias of various etiologies, and hematomas. Centrally located heman-
giomasmust be distinguished from the many osteolytic tumors and cystlike lesions that affect the jaws, as well as from both congenital and acquired arteriovenous aneurysms of the jaw. Care should be taken in excising or performing biopsies on hemangiomas, partly because of their tendency to uncontrolled hemorrhage and partly because of the difficulty of knowing the extent of the lesion, only a small part of which may be evident in the mouth.
Gingival hemangiomas may connect with similar lesions in the jawbone, and radiographic examination of the bone may not always reveal an abnormality of the trabecular architecture. Most such lesions are observed clinically as multilocular radiolucencies; therefore, when this radiographic pattern is observed, the lesion should be aspirated. Some central hemangiomas of bone represent arteriovenous malformations, and the blood coursing through them is under arterial pressure. A bright red aspirate is highly suggestive of central hemangioma and requires that imaging studies be instituted to confirm the clinical impression. Computed tomography, Doppler and conventional ultrasonography,radionuclide-labeled red cell scintigraphic scanning,and superselective microangio graphyare used to define the extent of bony hemangiomas, and radiographic examination of the affected tissues may reveal not only bony defects but also phleboliths in the cheek that mark the location of abnormal vessels. Hemorrhage from centrally located hemangiomas of the jaw is especially difficult to control, and surgery on hemangiomas should be attempted only when provision has been made beforehand to control any untoward hemorrhage that may occur (typed and crossmatched blood, splints, and means of tying off branches of the external carotid artery). In general, electrocoagulation and cryosurgery cause less postoperative hemorrhage than incision with a scalpel causes.
The treatment of hemangiomascontinues to be a difficult problem fraught with the danger of uncontrollable hemorrhage. Conventional surgical techniques have been largely replaced by cryosurgeryand laser surgery,often preceded by the injection of sclerosing solutions.Also, intravascular embolization with plastic spheres is now a commonly used and successful approach. Although radiation can be used to sclerose these lesions,the risk of inducing neoplastic and other degenerative changeslater in life is very high, and its use is now generally contraindicated, particularly in children. Many of the reported cases of malignant change in hemangiomas undoubtedly are the results of radiation treatment. Intralesional injection of corticosteroids is sometimes a successful alternative to surgery for hemangiomas in infants.
Hemangiomas of the skin and oral mucous membrane often coexist with similar lesions of the central nervous system and the meninges.A variety of such angiomatous syndromes have been described, with eponyms applied to both complete and incomplete variants of each syndrome. Although the skin and oral lesions are the most deforming and disfiguring lesions, the central nervous system lesions are often associated with serious problems of epilepsy, hemiplegia, mental retardation, and retinal changes.
Sturge-Weber syndrome(encephalofacial or encephalotrigeminal angiomatosis) is probably the most common of these malformations (see Figure 7-11). It is characterized by angiomatosis of the face (nevus flammeus), with a variable distribution sometimes matching the dermatomes of one or more trigeminal nerve divisions; leptomeningeal angiomas, particularly of the parietal and occipital lobes of the brain, with associated characteristic intracranial calcifications; contralateral hemiplegia; and one or more of the neurologic symptoms just mentioned. Oral changes occur in 40% of cases of this syndrome and may include massive growths of the gingiva and asymmetric jaw growth and tooth eruption sequence (due to differential blood flow to the affected area). Since many patients with this syndrome are treated for many years with phenytoin (Dilantin) as an anticonvulsant, a distinction needs to be made in these patients between gingival hypertrophy due to phenytoin and that due to angiomatous changes, particularly if gingivectomy is planned.The intraoral lesions in this syndrome classically occur on the same side of the body as other angiomas in the patient, but the classic pattern is not always found in either the distribution or the expression of the various components of the syndrome. Fortunately, this serious malformation is not of hereditary origin (compare with Rendu-Osler-Weber syndrome or hereditary hemorrhagic telangiectasia). Other (rarer) angiomatous syndromes are Maffucci’s syn-
drome(multiple angioma of the skin and enchondromas of bone) and von Hippel-Lindau disease(a familial syndrome involving hemangioblastomas in the retina and cerebellum, pancreatic and renal cysts, renal adenomas, hepatic hemangiomas, and multiple endocrine neoplasia)(see pertinent section). Conditions such as Sturge-Weber syndrome and von Hippel-Lindau disease, which involve a visible congenitally acquired external lesion (ie, a birthmark or “phakos”) and other systemic anomalies, are sometimes referred to as phakomatoses.
Many reviews and case reportsof both isolated oral hemangiomas and the various angiomatous syndromes are available and attest to the problems associated with treating these non-neoplastic lesions.
Sturge-Weber syndrome(encephalofacial or encephalotrigeminal angiomatosis) is probably the most common of these malformations (see Figure 7-11). It is characterized by angiomatosis of the face (nevus flammeus), with a variable distribution sometimes matching the dermatomes of one or more trigeminal nerve divisions; leptomeningeal angiomas, particularly of the parietal and occipital lobes of the brain, with associated characteristic intracranial calcifications; contralateral hemiplegia; and one or more of the neurologic symptoms just mentioned. Oral changes occur in 40% of cases of this syndrome and may include massive growths of the gingiva and asymmetric jaw growth and tooth eruption sequence (due to differential blood flow to the affected area). Since many patients with this syndrome are treated for many years with phenytoin (Dilantin) as an anticonvulsant, a distinction needs to be made in these patients between gingival hypertrophy due to phenytoin and that due to angiomatous changes, particularly if gingivectomy is planned.The intraoral lesions in this syndrome classically occur on the same side of the body as other angiomas in the patient, but the classic pattern is not always found in either the distribution or the expression of the various components of the syndrome. Fortunately, this serious malformation is not of hereditary origin (compare with Rendu-Osler-Weber syndrome or hereditary hemorrhagic telangiectasia). Other (rarer) angiomatous syndromes are Maffucci’s syn-
drome(multiple angioma of the skin and enchondromas of bone) and von Hippel-Lindau disease(a familial syndrome involving hemangioblastomas in the retina and cerebellum, pancreatic and renal cysts, renal adenomas, hepatic hemangiomas, and multiple endocrine neoplasia)(see pertinent section). Conditions such as Sturge-Weber syndrome and von Hippel-Lindau disease, which involve a visible congenitally acquired external lesion (ie, a birthmark or “phakos”) and other systemic anomalies, are sometimes referred to as phakomatoses.
Many reviews and case reportsof both isolated oral hemangiomas and the various angiomatous syndromes are available and attest to the problems associated with treating these non-neoplastic lesions.