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VASCULAR TUMORS VASCULAR TUMORS
| Date post: | 30-Nov-2014 |
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VASCULAR TUMORS
VASCULAR TUMORS
Classification
-Benign tumors
Heamangioma
Malformations
Non neoplastic proliferations
-Intermediate grade
Kaposi sarcoma
hemangioendothelioma
Malignant tumors
Hemangioendiotelioma
Angiosarcoma
Hemangiomas
Hemangiomas are the most common tumors of the head and neck in infancy and childhood, comprising approximately 7% of all benign soft tissue tumors .
Development
The hemangioma is a true vascular tumor that results from a overgrowth of normal vascular tissue .
It exhibits relatively rapid early growth until approximately 6 to 8 months of age (proliferative phase), followed by regression by 5 to 9 years of age (involutory phase).
It grows by “endothelial proliferation”. During the rapid growth phase, an increased number of mast cells is seen within the endothelial wall.
The majority of the hemangiomas in infants are noted by the parent within the first month of life.
Hemangiomas are initially noticed as an erythematous, macular patch, which progresses through a rapid proliferative phase whereby it changes its color and grows faster than the commensurate growth of the child.
By the time the patient is 12 months of age most hemangiomas have shown signs of involution. The process of involution is normally slow and will not be completed until the age of 5 to 9 years.
Clinical presentation
Hemangiomas are found in the superficial tissue, the deep tissue, or both and may affect organ systems such as the liver, lung, spleen, and gastrointestinal tract.
Deep hemangiomas involve muscle or visceral organs and, are more difficult to diagnose. Therefore, further diagnostic studies are required.
Intra-osseous hemangiomas are extremely rare. However the soft tissue lesion may deform the underlying skeleton.
The predilection for females is approximately a 3 :1 ratio.
Clinical presentation
On examination, the superficial hemangioma usually consists of a raised, reddish to purple tumor with a distinct margin.
In contrast, deep subcutaneous hemangiomas often have a deep bluish hue with normal overlying skin, making diagnosis more difficult.
Both the lesions are firm to palpation and do not pulsate or exhibit any thrills or bruits.
Investigations
Computed tomography (C. T .Scan) and Magnetic resonance imaging ( M. R. I) imaging techniques are used as diagnostic aids to document the extent of the deep hemangiomas.
Arteriography is rarely indicated for the diagnosis of a hemangiomas.
A proliferation of vascular channels filled with red blood cells, shown here beneath skin.
Management
Observation and parental support are the initial approaches in the management of maxillofacial hemangiomas.
If functional compromise such as visual change, airway or masticatory compromise, bleeding, ulceration, or infection occurs intervention is necessary.
This may initially involve cortico-steroids for rapidly proliferating lesions or therapy with interferon alfa-2a.
Surgery is generally reserved for small lesions and as a secondary procedure after initial therapy and involution.
Treatment modalities include routine excision, injection of sclerosing agents, cryotherapy, and ablation using an argon laser.
Lymphangiomas
Lymphangiomas are malformations of the lymphatic system, which is the network of vessels responsible for returning to the venous system excess fluid from tissues.
These malformations can occur at any age and may involve any part of the body, but 90% occur in children less than 2 years of age and involve the head and neck.
-Capillary lymphangiomas
Capillary lymphangiomas are composed of small, capillary-sized lymphatic vessels and are characteristically located in the epidermis.
-Cavernous lymphangiomas
Composed of dilated lymphatic channels, cavernous lymphangiomas characteristically invade surrounding tissues.
-Cystic hygromasCystic hygromas are large, macrocystic lymphangiomas filled with straw-colored, protein-rich fluid.
-Hemangiolymphangioma
hemangiolymphangiomas are lymphangiomas with a vascular component.
-Lymphangiomas may also be classified into microcystic, macrocystic, and mixed subtypes, according to the size of their cysts.
Microcystic lymphangiomas
Microcystic lymphangiomas are composed of cysts, each of which measures less than 2 cm3 in volume.
Macrocystic lymphangiomasMacrocystic lymphangiomas contain cysts measuring more than 2 cm3 in volume.Mixed lymphangiomasLymphangiomas of the mixed type contain both microcystic and macrocystic components.
Glomus tumor
A glomus tumor (also known as a "solitary glomus tumor,"solid glomus tumor or glomangioma) is a rare benign neoplasm arising from the glomus body and mainly found under the nail, on the fingertip or in the foot.
They account for less than 2% of all soft tissue tumors. Glomus tumors were first described by Hoyer in 1877, while the first complete clinical description was given by Masson in 1924.
Histologically, glomus tumors are made up of an afferent arteriole, anastomotic vessel, and collecting venule. These lesions should not be confused with paragangliomas, which were formerly also called glomus tumors in now-antiquated clinical usage.
Vascular Malformations
Vascular malformations are present at birth and unlike hemangiomas, do not go through a a “rapid proliferative phase” and they do not “involute”.
They grow commensurately with the patient.
Vascular Malformations - Types
Vascular malformations may be capillary, venous, arterial, or combinations of these.
Approximately 31% of these malformations are found in the head and neck region.
Vascular Malformations are divided into two categories: Low-flow and High-flow lesions.
Capillary, venous, and lymphatic malformations exhibit “low flow lesions”.
Arterial and arterio-venous malformations exhibit “high flow” and are capable of severe hemorrhage with significant morbidity.
Vascular malformations are thought to “result when there is interruption at a particular stage of development of a vessel”.
The type of vascular malformation that results depends on the stage at which normal morphogenesis is interrupted.
Thus, vascular malformations are sub-classified by tissue type into capillary, venous, arterial, lymphatic, and combinations thereof, with the type of malformation that develops depending on the type of tissue affected during abnormal development.
This results in recruitment of “collateral vessels” and dilatation of involved vessels.
Unlike the hemangioma, the vascular malformation exhibits a steady increase in growth, without signs of involution.
Clinical presentation
In many cases, the diagnosis of a vascular malformation can be made from the patient’s history.
Although present at birth, these lesions are often not identified immediately, but only later on when the lesion enlarges enough to be clinically identifiable. This is particularly true for intra-bony lesions.
Venous malformations are bluish, soft and easily compressible, and auscultation reveals no bruits.
These malformations can vary from superficial, localized, mucosal spongy ectasis to complex invasive lesions that permeate tissue planes and alter the regional anatomy.
Any maneuver that increases venous pressure (e.g.Valsalva maneuver or supine positioning) can temporarily enlarge a venous malformation.
The clinical absence of “pulsations or a thrill” generally indicates a low flow Venous vascular malformation.
Phleboliths that may be noted on radiographic examination are found only in low flow lesions.
Bacillary angiomatosis
is a form of angiomatosis associated with bacteria of the Bartonella genus
BA is characterised by the proliferation of blood vessels, resulting in them forming tumour-like masses in the skin and other organs
Kaposi Sarcoma
Kaposi's sarcoma is a tumor caused by human herpesvirus 8 (HHV8, also known as Kaposi's sarcoma-associated herpesvirus, KSHV).
It became more widely known as one of the AIDS-defining illnesses in the 1980s.
The viral cause for this cancer was discovered in 1994.
Although KS is now well-established to be caused by a viral infection, there is widespread lack of awareness of this even among persons at risk for KSHV/HHV-8 infection.
Abundant small branching blood vessels. Spindle cells.Intracellular hyaline globsExtravasated RBCs
Hemangioendothelioma
Hemangioendothelioma is used to describe a group of vascular neoplasms that may be considered benign as well as malignant, depending on the specific group member's activity.
Epithelioid sarcoma-like hemangioendothelioma
Spindle-cell hemangioendothelioma
Kaposiform hemangioendothelioma
Endovascular papillary angioendothelioma
Infantile hemangioendothelioma
Characteristic budding, hobnail-like endothelial cells visible.
Angiosarcoma
Angiosarcoma is a malignant neoplasm of endothelial-type cells that line vessel walls. This may be in reference to blood (hemangiosarcoma) or lymphatic vessels (lymphangiosarcoma).
The images show abundant small blood vessels lined by large atypical endothelial cells
Hemangiopericytoma
A hemangeopericytoma (HPC) is a type of soft tissue sarcoma that originates in the pericytes in the walls of capillaries. When inside the nervous system, although not strictly a meningioma tumor, it is a meningeal tumor with a special aggressive behavior. It was first characterized in 1942
Tumor cells can be fibroblastic, myxoid, or pericytic. These tumors, in contrast to meningiomas, do not stain with epithelial membrane antigen.
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