Vascular tumors are abnormal growths composed of cells that form blood or lymph vessels. These growths can develop in various parts of the body, including the skin, internal organs, and tissues beneath the skin. They represent a diverse group of conditions, each with distinct characteristics and behaviors.
What Are Vascular Tumors?
Vascular tumors are defined by their origin from endothelial cells, which line the inside of blood vessels, or from lymphatic vessel cells. These growths are distinct from vascular malformations, which are developmental errors in blood vessel formation rather than proliferative growths. Vascular tumors are categorized primarily as either benign (non-cancerous) or malignant (cancerous), with benign forms being much more common.
Benign vascular tumors, also known as angiomas, are slow-growing and do not spread to other parts of the body. They are composed of blood vessel cells and can vary widely in appearance and location. These non-cancerous growths may cause symptoms due to their size or position, but they do not pose a direct threat to life by spreading.
Malignant vascular tumors, such as angiosarcomas, are less common but are aggressive and can spread rapidly. These cancerous growths originate from the lining of blood vessels and can affect various organs and tissues throughout the body. The distinction between benign and malignant forms is a primary concern for diagnosis and treatment planning due to their differing implications for patient health.
Common Types of Vascular Tumors
Hemangiomas are common benign vascular tumors, particularly in infants. Infantile hemangiomas often appear weeks after birth as a red spot, characterized by a rapid growth phase followed by spontaneous regression, fading during early childhood. They are the most common type of vascular tumor in children, accounting for over 90% of hemangiomas.
Vascular malformations differ from hemangiomas as they are present at birth and grow proportionally with the child, without a phase of spontaneous regression. These malformations involve errors in the development of blood vessels and can include arteriovenous malformations (AVMs), which are abnormal connections between arteries and veins, as well as venous malformations and lymphatic malformations. Unlike tumors, malformations do not consist of a solid mass but rather dilated, often fluid-filled channels.
Angiosarcomas are rare but aggressive malignant vascular tumors. They can form in blood vessels or lymph vessels in any part of the body, often appearing in soft tissue near the skin, or in deeper organs like the liver, spleen, or lung. Angiosarcomas are characterized by high vascularity and rapid proliferation, requiring prompt and aggressive treatment due to their cancerous nature.
Recognizing Symptoms and Diagnosis
Vascular tumors present with a wide range of symptoms depending on their size, location, and type. A tumor on the skin might appear as a visible lesion, such as a red or bluish discoloration, or a raised lump. Internal tumors, however, may cause pain, swelling, or functional impairment if they press on nerves or organs. For example, tumors in the pulmonary artery can lead to difficulty breathing or shortness of breath.
The diagnostic process begins with a physical examination and a review of health history. Imaging techniques play a key role in characterizing these tumors, with ultrasound often used for superficial lesions to assess vascularity. Magnetic Resonance Imaging (MRI) is a comprehensive tool for detailing the lesion, evaluating adjacent structures, and assessing its blood flow characteristics. CT scans also provide detailed information on tumor size, location, and any associated features like calcifications or hemorrhage.
While imaging provides valuable insights, a biopsy remains the definitive method for confirming the diagnosis and determining the specific type of vascular tumor. This procedure involves removing cells or tissue for microscopic examination. In some cases, a biopsy may not be necessary if imaging and clinical presentation are highly characteristic of a common benign tumor like an infantile hemangioma.
Management and Treatment Options
The approach to managing vascular tumors is individualized, based on the tumor’s type, size, location, symptoms, and whether it is benign or malignant. For many benign, asymptomatic lesions, observation may be sufficient, involving regular monitoring for changes.
Medical therapies are used for certain types of vascular tumors. Beta-blockers are commonly prescribed for some hemangiomas to help reduce their size. For malignant tumors like angiosarcomas, chemotherapy and radiation therapy may be employed to target cancerous cells, aiming to control tumor growth and prevent further spread.
Surgical removal is an option for accessible tumors causing problems like pain or functional impairment, or for malignant tumors that can be fully excised. Procedures like embolization or sclerotherapy are also utilized, particularly for vascular malformations or tumors with high blood flow. Embolization involves blocking the blood vessels supplying the tumor with special materials, while sclerotherapy involves injecting a substance to shrink and collapse abnormal vessels.