Cardiovascular Tumours and Tumour-Like Lesions

Understand the basic terminology applying to benign and malignant tumours
Understand the principles of morphological tumour diagnosis, grading and staging

• Growth Disorders

Note that while neoplasm and tumour do have subtly different meanings (as described in the above post), many people use them interchangeably. I will try and stick to the definitions I gave in the above linked post.

Discuss the common neoplasms of the heart

Neoplasms in the heart are rare, and malignant neoplasms are even rarer. The most common heart neoplasm is a myxoma, which is a benign neoplasm. Myxomas are usually located in the atrium, particularly in the left atrium, near the fossa ovalis. They may be sessile, meaning that they basically look like a lump coming out of the wall of the heart, or they may be pedunculated, meaning that they are joined to the side of the wall via a stalk. Pedunculated myxomas look a little bit like a wrecking ball. Roughly 10% of people with myxomas have a genetic syndrome called Carney's complex.

Discuss the common neoplasms of the blood vessels

Neoplasms of the blood vessels are much more common than neoplasms of the heart. Most benign neoplasms are haemangiomas (from blood vessels), but there are also glomus tumours (from cells surrounding endothelial cells and lymphangiomas (from lymph vessels). Malignant neoplasms of blood vessels tend to be sarcomas, rather than carcinomas. In this post, I will discuss haemangiomas, Kaposi Sarcoma, and angiosarcoma.

Juvenile haemangiomas are haemangiomas acquired before or around the time of birth. Haemangiomas that are present at birth are called congenital haemangiomas and usually disappear over the first year of life. Haemangiomas that arise a few weeks after birth (usually due to changes induced by switching from prenatal to postnatal circulation) are called infantile haemangiomas. Infantile haemangiomas, which are usually found on the head and neck, tend to grow rapidly before fading and usually disappear by age 10.

There are three main types of acquired haemangiomas (i.e. haemangiomas acquired later in life). The three main types are capillary haemangiomas, cavernous haemangiomas, and lobular capillary haemangiomas (also known as pyogenic granulomas). Capillary haemangiomas, as the name suggests, primarily affect capillaries and are found in the skin and subcutaneous tissues. Cavernous haemangiomas primarily affect veins and can be large enough to compress surrounding structures. Lobular capillary haemangiomas are often found on the skin, gums, and oral mucosa. Also, despite the fact that lobular capillary haemangiomas are also called pyogenic granulomas, they do not form pus, nor do they form granulomas.

Kaposi Sarcoma is an intermediate-grade neoplasm, meaning that it is only locally aggressive and/or has a low risk of metastasis. There are four main forms of Kaposi Sarcoma: classic, endemic African, transplant-associated, and HIV-associated. All four forms are due to Human Herpes Virus 8 (HHV8) and progress from the patch stage through to the plaque stage and finally through to the nodule stage.

Angiosarcoma is a malignant neoplasm, meaning that it is locally aggressive and has a high risk of metastasis. They can occur nearly anywhere, but usually in the skin, soft tissue, breast, and liver. Liver angiosarcomas are often associated with environmental exposure to carcinogens, such as arsenic, and can take a long time to form. Angiosarcomas are quite aggressive and the five-year survival rate is fairly low, at only around 30%.

Discuss the common non-neoplastic tumour-like lesions and malformations of the CVS

There are many lesions that look like neoplasms but aren't, and since it's important to know what you're dealing with when patients present with something lumpy, I'll discuss them here.

Several vascular malformations can look like tumours. Tumour-like vascular malformations in slow-flowing vessels include naevus flammeus, also known as a "firemark" or "Port Wine stain," and congenital lymphangioma, which may be associated with chromosomal abnormalities. Tumour-like vascular malformations in fast-flowing blood vessels include cerebrovascular arteriovenous malformation.

Varicose veins are dilated and tortuous veins that have incompetent venous valves, resulting in pooling of blood and veins that stick out. Varicose veins usually occur in superficial veins of the leg and thigh, but can also occur in other vessels such as oesophageal veins and anorectal veins. In fact, haemorrhoids are essentially just varicose veins in the anus. If veins in the scrotum or spermatic cord are dilated, this is called varicocoele.