Hemangioendothelioma
Hemangioendothelioma, Epithelioid
Kasabach-Merritt Syndrome
Hemangiosarcoma
Neoplasms, Vascular Tissue
Vascular Neoplasms
Hemangioma
Endothelium, Lymphatic
Labyrinth Diseases
Ear Neoplasms
Sarcoma, Kaposi
Blue Toe Syndrome
Spinal Neoplasms
Fatal Outcome
Expression of L-selectin ligands by transformed endothelial cells enhances T cell-mediated rejection. (1/119)
Recent immunohistochemical studies have suggested that L-selectin ligands may be implicated in the infiltration of tumors and rejected transplants by lymphocytes. In the present study, polyoma-middle T Ag-transformed endothelial cells (H.end), which typically form in vivo immunogenic vascular tumors resembling Kaposi's sarcoma, were engineered to express L-selectin ligands by stable transfection with a cDNA encoding alpha(1,3/4)-fucosyltransferase (H.endft). The ability of these cells to form tumors in the s.c. tissues of normal and immunocompromised mice was then compared with that of H.end cells transfected with the hygromycin-resistance vector only (H. endhygro). H.endhygro cells rapidly formed local and metastatic tumors in normal syngeneic mice, leading to death within 2-3 mo postinjection. By contrast, tumors derived from H.endft cells displayed a slower rate of growth, an absence of metastasis, and marked lymphocyte infiltration. Animals bearing these tumors survived for a significantly longer duration than animals injected with H.endhygro cells. Alternatively, H.endft and H.endhygro cells formed tumors with comparable aggressiveness in immunocompromised mice, resulting in animal death within 3 wk of injection. H.endft but not H.endhygro cells supported L-selectin-dependent adhesion and cytolytic T cell activity in vitro. Taken together, our observations indicate that the in situ expression of fucosyltransferase may significantly influence the cellular immune response in endothelioma tumors. These results may be relevant in understanding the development of vascular opportunistic tumors such as Kaposi's sarcoma. (+info)In vivo gene therapy with interleukin-12 inhibits primary vascular tumor growth and induces apoptosis in a mouse model. (2/119)
Interleukin-12 is proposed to have anti-neoplastic activity on the basis of both its anti-angiogenic and immunologic effects. Gene gun therapy with interleukin-12 cDNA into the peritumoral area of immunocompetent 129/J mice with life-threatening primary vascular tumors reduced tumor volume 7.5-fold and almost tripled the duration of mouse survival, in contrast with luciferase-bombarded control mice. Epidermal expression of mouse interleukin-12 elevated tumoral and serum levels of interferon-gamma and tumor necrosis factor-alpha, increased the tumoral populations of T lymphocyte and natural killer cells, and induced tumor apoptosis. Gene transfer of interleukin-12 had little effect on tumor volumes and survival of tumor-bearing athymic nude mice, emphasizing the requirement for T cell directed cellular immunity. Peritumoral gene gun introduction of interleukin-12 may be a novel, cost-effective approach to limit the growth and associated mortality of life-threatening tumors. (+info)Formation of transformed endothelial cells in the absence of VEGFR-2/Flk-1 by Polyoma middle T oncogene. (3/119)
The middle T antigen of murine Polyomavirus (PymT) rapidly transforms endothelial cells leading to vascular malformations reminiscent of endothelial tumors or hemangiomas. Flk-1, a receptor tyrosine kinase which is activated upon binding of its ligand VEGF, is predominantly expressed in endothelial cells and essential for the formation of blood vessels since absence of Flk-1 prevents the development of mature endothelial cells in mice and in ES-cell differentiation experiments. To investigate the role of Flk-1 in PymT-induced vascular tumor formation, we studied the expression of Flk-1 and VEGF in PymT-transformed endothelial cells (Endothelioma cells, END. cells). The receptor and its ligand were both expressed in END. cells suggesting that a VEGF/Flk-1 autocrine loop might be causally involved in the formation of vascular tumors. To test this hypothesis, ES cells lacking Flk-1 were generated and the transforming potential of PymT was analysed after in vitro differentiation. Flk-1(-/-) END. cell lines were established which are morphologically identical to flk-1(+/+) END. cells and which express several markers characteristic for endothelial cells. This result suggests that PymT functionally replaces the requirement of Flk-1 in expansion and/or survival of endothelial progenitor cells. Therefore, flk-1(-/-) END. cells provide a powerful tool to dissect the downstream signaling pathways of Flk-1. (+info)The generation of endostatin is mediated by elastase. (4/119)
Endostatin, a potent inhibitor of angiogenesis and tumor growth, is a COOH-terminal fragment of collagen XVIII derived through cleavage of an Ala-His linkage by an as yet unidentified endostatin-processing enzyme. Endostatin was originally isolated from the conditioned medium of hemangioendothelioma (EOMA) cells. By investigating the processing of collagen XVIII to endostatin by EOMA cells, we show here that the generation of endostatin can be mediated by an elastase activity. We also show that several members of the elastase family can act as an endostatin-processing enzyme by specifically cleaving the Ala-His linkage and releasing endostatin from a precursor molecule. We further suggest that the generation of endostatin from collagen XVIII is at least a two-step process, involving a metal-dependent early step and an elastase activity-dependent final step. (+info)Hemangioendothelioma of the parotid gland in infants: sonography and correlative MR imaging. (5/119)
BACKGROUND AND PURPOSE: Hemangioendothelioma is the most common parotid gland tumor of childhood, and is diagnosed on clinical grounds, supported by imaging findings. Previous work has suggested that MR is the best imaging technique for assessment of parotid hemangioendothelioma. Demonstration of a reliable sonographic appearance would reduce the need for MR imaging in infants with this lesion. METHODS: We performed high-frequency sonography (including color Doppler and power Doppler imaging) in three patients, each with a diagnosis of parotid hemangioendothelioma confirmed by clinical follow-up. Two patients were also examined with MR imaging and labeled red cell scintigraphy. RESULTS: All sonographic studies showed a homogeneous mass enlarging and replacing most or all of the visualized parotid gland, with a lobular internal structure, fine echogenic internal septations, and a mildly lobulated contour. Color Doppler and power Doppler imaging showed extremely high vascularity within the mass. Correlative MR images in two infants showed a well-defined lesion with uniform intense contrast enhancement. Labeled red cell scintigraphy showed a well-defined area of intense activity. CONCLUSION: In the presence of a typical clinical history, sonography and clinical follow-up alone may prove to be sufficient for safe management of parotid hemangioendothelioma. MR imaging or labeled red cell scintigraphy may only be required if the sonographic features are atypical. These findings require confirmation in a larger series of patients. (+info)Vascular endothelial growth factor receptor-3 (VEGFR-3): a marker of vascular tumors with presumed lymphatic differentiation, including Kaposi's sarcoma, kaposiform and Dabska-type hemangioendotheliomas, and a subset of angiosarcomas. (6/119)
Recently, a novel monoclonal antibody to vascular endothelial growth factor receptor 3 (VEGFR-3), a tyrosine kinase receptor expressed almost exclusively by lymphatic endothelium in the adult, has been shown to react with a small number of cases of Kaposi's sarcoma (KS) and cutaneous lymphangiomas. We sought to extend these studies to a large number of well-characterized vascular neoplasms to evaluate diagnostic uses of this antibody and to determine whether it defines them in a thematic fashion. Formalin-fixed, paraffin-embedded sections from 70 vascular tumors were immunostained with antibodies to VEGFR-3 von Willebrand factor (vWF), and CD31. Anti-VEGFR-3 was positive in 23 of 24 KS, 8 of 16 angiosarcomas (AS), 6 of 6 kaposiform hemangioendotheliomas, 4 of 4 Dabska tumors, and 2 of 13 hemangiomas. Positively staining angiosarcomas were characterized either by a prominent lymphocytic component, a hobnail endothelial cell similar to that encountered in the Dabska tumor, or spindled areas resembling KS. No VEGFR-3 expression was noted in any cases of epithelioid hemangioendothelioma, pyogenic granuloma, littoral angioma, or stasis dermatitis. vWF expression was seen in 10 of 13 KS; 13 of 14 AS; 4 of 5 kaposiform hemangioendotheliomas; and all Dabska tumors, hemangiomas, lymphangiomas, epithelioid hemangioendotheliomas, vascular malformations, stasis dermatitis, and splenic littoral angiomas. CD31 expression was present in 12 of 13 KS, 13 of 14 AS, and in all other cases. Expression of VEGFR-3 is a very sensitive marker of KS, kaposiform, and Dabska-type hemangioendotheliomas, suggesting that all show at least partial lymphatic endothelial differentiation. Expression of VEGFR-3 does not reliably discriminate KS from AS. However, the expression of VEGFR-3 by certain AS having Kaposi-like areas, a prominent lymphocytic infiltrate, or hobnail endothelium may define subset(s) having phenotypic, if not pathogenetic and biologic, differences. (+info)Sedation for intractable distress of a dying patient: acute palliative care and the principle of double effect. (7/119)
Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded the Kenneth B. Schwartz Center at MGH. The Schwartz Center is a nonprofit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The Center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. The case presented is of a young man dying of recurrent epithelioid hemangioendothelioma, distressed with stridor and severe pain, whose poorly controlled symptoms were successfully treated with an infusion of propofol, titrated to provide effective comfort in the last few hours of the patient's life. The tenet of double effect, which allows aggressive treatment of suffering in spite of foreseeable but unintended consequences, is reviewed. The patient's parents were invited and contributed to the Rounds, providing compelling testimony to the power of the presence of clinicians at the time of death and the importance of open communication about difficult ethical issues. (+info)Treatment options for other hepatic malignancies. (8/119)
1. Resection rates for cholangiocarcinoma (unrelated to primary sclerosing cholangitis) have increased to 54% to 79%, and the subsequent 5-year survival rates are 24% to 31%. 2. Multimodality approaches involving various combinations of chemotherapy, irradiation, and surgery increasingly are being used to treat cholangiocarcinoma. 3. The role of liver transplantation in the management of cholangiocarcinoma is limited by the perception that it is inappropriate to use scarce organs when 5-year survival rates are 25%. 4. Liver transplantation is an important intervention in patients with tumors that remain unresectable after chemotherapy. The role of liver transplantation in patients with extrahepatic disease that responds to chemotherapy is controversial. Careful timing of surgery is required to avoid secondary drug resistance. 5. Liver transplantation has been successfully applied to a range of rare hepatic malignancies, but small numbers preclude strong recommendations on the appropriateness of this practice. (+info)Hemangioendothelioma is a rare type of vascular tumor, which means it arises from the endothelial cells that line the blood vessels. It can occur in various parts of the body, but it most commonly involves the soft tissues and bones. Hemangioendotheliomas are often classified as borderline malignant tumors because they can behave either indolently (like a benign tumor) or aggressively (like a malignant tumor), depending on their specific type and location.
There are several subtypes of hemangioendothelioma, including:
1. Epithelioid hemangioendothelioma: This subtype typically affects young adults and can involve various organs, such as the liver, lungs, or soft tissues. It tends to have a more indolent course but can metastasize in some cases.
2. Kaposiform hemangioendothelioma: This is an aggressive subtype that usually occurs in infants and children. It often involves the skin and soft tissues, causing local invasion and consumptive coagulopathy (Kasabach-Merritt phenomenon).
3. Retiform hemangioendothelioma: A rare and low-grade malignant tumor that typically affects the skin and subcutaneous tissue of adults. It has a favorable prognosis with a low risk of metastasis.
4. Papillary intralymphatic angioendothelioma (PILA): This is a rare, slow-growing tumor that usually occurs in the head and neck region of children and young adults. It has an excellent prognosis with no reported cases of metastasis or recurrence after complete surgical resection.
Treatment for hemangioendotheliomas typically involves surgical excision when possible. Other treatment options, such as radiation therapy, chemotherapy, or targeted therapies, may be considered depending on the tumor's location, size, and behavior. Regular follow-up is essential to monitor for potential recurrence or metastasis.
Epithelioid Hemangioendothelioma is a rare type of vascular tumor that can develop in various parts of the body, such as the liver, lungs, bones, and soft tissues. It is characterized by the abnormal growth of endothelial cells, which line the interior surface of blood vessels.
Epithelioid Hemangioendothelioma is classified as a borderline malignant tumor, meaning it has the potential to behave in a benign or malignant manner. The tumor typically grows slowly and may remain localized for an extended period, but it can also metastasize (spread) to other parts of the body.
The epithelioid variant of Hemangioendothelioma is named for its distinctive appearance under a microscope. The tumor cells are large and have an epithelial-like morphology, which means they resemble the cells that make up the outer layer of the skin and other organs.
Clinical presentation and management of Epithelioid Hemangioendothelioma depend on the location and extent of the tumor. Treatment options may include surgery, radiation therapy, chemotherapy, or a combination of these approaches. Regular follow-up is essential to monitor for any signs of recurrence or progression.
Kasabach-Merritt syndrome (KMS) is a rare but serious condition characterized by the combination of a large hemangioma or tufted angioma (benign vascular tumors) with severe thrombocytopenia (low platelet count) and consumptive coagulopathy (a disorder of blood clotting).
The syndrome is named after the two physicians who first described it in 1940. It primarily affects infants, with about 70% of cases diagnosed before the age of one month.
In KMS, the hemangioma or tufted angioma grows rapidly and becomes a consumptive coagulopathy due to platelet trapping within the lesion, leading to profound thrombocytopenia. This can result in bleeding complications, which can be life-threatening if not promptly treated.
The treatment of KMS typically involves a combination of medical management (such as corticosteroids, interferon, and vincristine) and surgical intervention to remove the hemangioma or tufted angioma. In some cases, embolization of the lesion may also be considered.
Hemangiosarcoma is a type of cancer that arises from the cells that line the blood vessels (endothelial cells). It most commonly affects middle-aged to older dogs, but it can also occur in cats and other animals, as well as rarely in humans.
This cancer can develop in various parts of the body, including the skin, heart, spleen, liver, and lungs. Hemangiosarcomas of the skin tend to be more benign and have a better prognosis than those that arise internally.
Hemangiosarcomas are highly invasive and often metastasize (spread) to other organs, making them difficult to treat. The exact cause of hemangiosarcoma is not known, but exposure to certain chemicals, radiation, and viruses may increase the risk of developing this cancer. Treatment options typically include surgery, chemotherapy, and/or radiation therapy, depending on the location and stage of the tumor.
A neoplasm of vascular tissue is an abnormal growth or mass of cells in the blood vessels or lymphatic vessels. These growths can be benign (non-cancerous) or malignant (cancerous). Benign neoplasms, such as hemangiomas and lymphangiomas, are typically not harmful and may not require treatment. However, they can cause symptoms if they grow large enough to press on nearby organs or tissues. Malignant neoplasms, such as angiosarcomas, are cancerous and can invade and destroy surrounding tissue, as well as spread (metastasize) to other parts of the body. Treatment for vascular tissue neoplasms depends on the type, size, location, and stage of the growth, and may include surgery, radiation therapy, chemotherapy, or a combination of these.
Vascular neoplasms are a type of tumor that develops from cells that line the blood vessels or lymphatic vessels. These tumors can be benign (non-cancerous) or malignant (cancerous). Benign vascular neoplasms, such as hemangiomas and lymphangiomas, are usually harmless and may not require treatment unless they cause symptoms or complications. Malignant vascular neoplasms, on the other hand, are known as angiosarcomas and can be aggressive, spreading to other parts of the body and potentially causing serious health problems.
Angiosarcomas can develop in any part of the body but are most commonly found in the skin, particularly in areas exposed to radiation or chronic lymph edema. They can also occur in the breast, liver, spleen, and heart. Treatment for vascular neoplasms depends on the type, location, size, and stage of the tumor, as well as the patient's overall health. Treatment options may include surgery, radiation therapy, chemotherapy, or a combination of these approaches.
A hemangioma is a benign (noncancerous) vascular tumor or growth that originates from blood vessels. It is characterized by an overgrowth of endothelial cells, which line the interior surface of blood vessels. Hemangiomas can occur in various parts of the body, but they are most commonly found on the skin and mucous membranes.
Hemangiomas can be classified into two main types:
1. Capillary hemangioma (also known as strawberry hemangioma): This type is more common and typically appears during the first few weeks of life. It grows rapidly for several months before gradually involuting (or shrinking) on its own, usually within the first 5 years of life. Capillary hemangiomas can be superficial, appearing as a bright red, raised lesion on the skin, or deep, forming a bluish, compressible mass beneath the skin.
2. Cavernous hemangioma: This type is less common and typically appears during infancy or early childhood. It consists of large, dilated blood vessels and can occur in various organs, including the skin, liver, brain, and gastrointestinal tract. Cavernous hemangiomas on the skin appear as a rubbery, bluish mass that does not typically involute like capillary hemangiomas.
Most hemangiomas do not require treatment, especially if they are small and not causing any significant problems. However, in cases where hemangiomas interfere with vital functions, impair vision or hearing, or become infected, various treatments may be considered, such as medication (e.g., corticosteroids, propranolol), laser therapy, surgical excision, or embolization.
The lower extremity, also known as the lower limb, consists of the bones that make up the leg and foot. In humans, these bones include:
1. Femur: This is the thigh bone, and it is the longest and strongest bone in the human body.
2. Patella: Also known as the kneecap, this is a small triangular bone located at the front of the knee joint.
3. Tibia: This is the larger of the two bones in the lower leg, also known as the shin bone.
4. Fibula: This is the smaller of the two bones in the lower leg, located on the lateral side of the tibia.
5. Tarsal bones: These are seven small bones located in the foot, which articulate with the tibia and fibula to form the ankle joint.
6. Metatarsal bones: These are five long bones located in the midfoot, which connect to the phalanges (toes) at one end and the tarsal bones at the other.
7. Phalanges: These are fourteen small bones located in the toes, similar in structure to the phalanges in the fingers of the hand.
Together, these bones provide support, stability, and mobility to the lower extremity, allowing for activities such as walking, running, and jumping.
The endothelium is a thin layer of cells that lines the interior surface of blood vessels and lymphatic vessels. The lymphatic endothelium, specifically, is the type of endothelial cell that forms the walls of lymphatic vessels. These vessels are an important part of the immune system and play a crucial role in transporting fluid, waste products, and immune cells throughout the body.
The lymphatic endothelium helps to regulate the movement of fluids and cells between the tissues and the bloodstream. It also contains specialized structures called valves that help to ensure the unidirectional flow of lymph fluid towards the heart. Dysfunction of the lymphatic endothelium has been implicated in a variety of diseases, including lymphedema, inflammation, and cancer metastasis.
Labyrinth diseases refer to conditions that affect the inner ear's labyrinth, which is the complex system of fluid-filled channels and sacs responsible for maintaining balance and hearing. These diseases can cause symptoms such as vertigo (a spinning sensation), dizziness, nausea, hearing loss, and tinnitus (ringing in the ears). Examples of labyrinth diseases include Meniere's disease, labyrinthitis, vestibular neuronitis, and benign paroxysmal positional vertigo. Treatment for these conditions varies depending on the specific diagnosis but may include medications, physical therapy, or surgery.
Ear neoplasms refer to abnormal growths or tumors that occur in the ear. These growths can be benign (non-cancerous) or malignant (cancerous) and can affect any part of the ear, including the outer ear, middle ear, inner ear, and the ear canal.
Benign ear neoplasms are typically slow-growing and do not spread to other parts of the body. Examples include exostoses, osteomas, and ceruminous adenomas. These types of growths are usually removed surgically for cosmetic reasons or if they cause discomfort or hearing problems.
Malignant ear neoplasms, on the other hand, can be aggressive and may spread to other parts of the body. Examples include squamous cell carcinoma, basal cell carcinoma, and adenoid cystic carcinoma. These types of tumors often require more extensive treatment, such as surgery, radiation therapy, and chemotherapy.
It is important to note that any new growth or change in the ear should be evaluated by a healthcare professional to determine the nature of the growth and develop an appropriate treatment plan.
Kaposi sarcoma (KS) is a type of cancer that causes abnormal growths in the skin, lymph nodes, or other organs. It is caused by the Kaposi sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV8). There are several forms of KS, including:
1. Classic KS: This form primarily affects older men of Mediterranean, Middle Eastern, or Ashkenazi Jewish descent. It tends to progress slowly and mainly involves the skin.
2. Endemic KS: Found in parts of Africa, this form predominantly affects children and young adults, regardless of their HIV status.
3. Immunosuppression-associated KS: This form is more aggressive and occurs in people with weakened immune systems due to organ transplantation or other causes.
4. Epidemic KS (AIDS-related KS): This is the most common form of KS, seen primarily in people with HIV/AIDS. The widespread use of antiretroviral therapy (ART) has significantly reduced its incidence.
KS lesions can appear as red, purple, or brown spots on the skin and may also affect internal organs such as the lungs, lymph nodes, or gastrointestinal tract. Symptoms vary depending on the location of the lesions but often include fever, fatigue, weight loss, and swelling in the legs or abdomen. Treatment options depend on the extent and severity of the disease and may involve local therapies (e.g., radiation, topical treatments), systemic therapies (e.g., chemotherapy, immunotherapy), or a combination of these approaches.
Blue toe syndrome, also known as acrocyanosis or digital ischemia, is a medical condition characterized by the bluish discoloration of the toes due to insufficient blood supply. This can occur due to various reasons such as chilblains, vasospasms, blood clots in the small arteries of the feet, or certain medications that affect blood flow. Prolonged exposure to cold temperatures, smoking, and underlying health conditions like Raynaud's disease, Buerger's disease, or autoimmune disorders can increase the risk of developing blue toe syndrome. Severe cases may require medical intervention such as medication, surgery, or lifestyle changes to improve blood flow and prevent tissue damage.
Liver neoplasms refer to abnormal growths in the liver that can be benign or malignant. Benign liver neoplasms are non-cancerous tumors that do not spread to other parts of the body, while malignant liver neoplasms are cancerous tumors that can invade and destroy surrounding tissue and spread to other organs.
Liver neoplasms can be primary, meaning they originate in the liver, or secondary, meaning they have metastasized (spread) to the liver from another part of the body. Primary liver neoplasms can be further classified into different types based on their cell of origin and behavior, including hepatocellular carcinoma, cholangiocarcinoma, and hepatic hemangioma.
The diagnosis of liver neoplasms typically involves a combination of imaging studies, such as ultrasound, CT scan, or MRI, and biopsy to confirm the type and stage of the tumor. Treatment options depend on the type and extent of the neoplasm and may include surgery, radiation therapy, chemotherapy, or liver transplantation.
Spinal neoplasms refer to abnormal growths or tumors found within the spinal column, which can be benign (non-cancerous) or malignant (cancerous). These tumors can originate in the spine itself, called primary spinal neoplasms, or they can spread to the spine from other parts of the body, known as secondary or metastatic spinal neoplasms. Spinal neoplasms can cause various symptoms, such as back pain, neurological deficits, and even paralysis, depending on their location and size. Early diagnosis and treatment are crucial to prevent or minimize long-term complications and improve the patient's prognosis.
A fatal outcome is a term used in medical context to describe a situation where a disease, injury, or illness results in the death of an individual. It is the most severe and unfortunate possible outcome of any medical condition, and is often used as a measure of the severity and prognosis of various diseases and injuries. In clinical trials and research, fatal outcome may be used as an endpoint to evaluate the effectiveness and safety of different treatments or interventions.
The thoracic vertebrae are the 12 vertebrae in the thoracic region of the spine, which is the portion between the cervical and lumbar regions. These vertebrae are numbered T1 to T12, with T1 being closest to the skull and T12 connecting to the lumbar region.
The main function of the thoracic vertebrae is to provide stability and support for the chest region, including protection for the vital organs within, such as the heart and lungs. Each thoracic vertebra has costal facets on its sides, which articulate with the heads of the ribs, forming the costovertebral joints. This connection between the spine and the ribcage allows for a range of movements while maintaining stability.
The thoracic vertebrae have a unique structure compared to other regions of the spine. They are characterized by having long, narrow bodies, small bony processes, and prominent spinous processes that point downwards. This particular shape and orientation of the thoracic vertebrae contribute to their role in limiting excessive spinal movement and providing overall trunk stability.