Sometimes, parts of our body grow too much.
This can make a small lump. Some lumps are not bad. They stay in one spot. Other lumps can be bad. They can spread to other places. Doctors help us stay well. Have you ever felt a bump?
Sometimes, parts of our body grow too much.
This can make a small lump. This growth is called a neoplasm.
Some lumps are not bad. They stay in one spot. These are called benign. A skin mole is one kind.
Other lumps are bad. They can spread to other places. These are called cancer.
Lumps can happen when cells grow too fast. This happens because of damage to the cells.
Doctors use special tools to see these lumps. They want to help us stay well.
A neoplasm is an abnormal growth of body tissue.
This growth is not like the healthy tissue around it. It keeps growing even if the original trigger is gone. This often forms a mass. We call this mass a tumor.
There are different kinds of neoplasms. Benign neoplasms are not cancer. They stay in one place and do not turn into cancer. Skin moles are one example.
Some growths are more serious. These are malignant neoplasms. We call these cancers. They can invade and destroy nearby tissue. They can also spread to other parts of the body.
Why do these growths happen? It often starts with DNA damage. DNA is the code inside our cells. When this code changes, cells may divide too much. This can happen from many things. Tobacco smoke or UV light from the sun can cause damage.
Sometimes, the cells cannot fix their own DNA. This is because of a problem with DNA repair. If the repair system fails, damage builds up. This can lead to cancer.
Doctors use tools like CT scans to study these growths. They want to see how they work and how to help.
A neoplasm is an abnormal and excessive growth of body tissue. The word comes from Ancient Greek words meaning "new formation."
This growth is different from the healthy tissue around it. It does not coordinate its growth with the rest of the body. Even if the original trigger for the growth is removed, it keeps growing. This often forms a solid or fluid-filled mass. We often call this mass a tumor or a neoplasm.
There are several main groups of these growths. Benign neoplasms are non-cancerous and stay in one place. Examples include skin moles or uterine fibroids. They do not turn into cancer. Some growths are called carcinoma in situ. These are localized and do not destroy nearby tissue, but they might turn into cancer later. Malignant neoplasms are what we call cancer. These can invade and destroy the tissue around them. They can also form metastases, which means they spread to other parts of the body.
Scientists have studied how these growths work for a long time. They use math and mechanics to understand them. For example, they look at vascular tumors like hemangiomas. These are made of blood or lymph vessels. Researchers view them as a solid skeleton made of sticky cells. This skeleton holds an organic liquid in the spaces between cells. Recent experiments show that active growth usually happens at the outer edges. They also found that stiff tissue nearby can stop a tumor from growing.
Many factors can cause these growths to start. A major cause is DNA damage within a single cell. DNA is the code that tells cells how to work. On average, a human cell has more than 10,000 new damages every day. Some things make this damage happen more often. Tobacco smoke and UV light from the sun can cause damage. An infection called Helicobacter pylori can also contribute to gastric cancer. High levels of bile acids in the colon are another factor.
Sometimes the body's natural repair system fails. Most cancers are sporadic, meaning they are not passed down through families. About 70% of malignant neoplasms fall into this group. In these cases, the cells have a hard time fixing their DNA. This can happen because of genetic mutations or epigenetic alterations. Epigenetic alterations are changes that silence the genes meant to repair DNA. When repair genes like MGMT or MLH1 are silenced, damage builds up quickly. This build-up leads to more mutations and more abnormal growth.
A neoplasm is a type of abnormal and excessive tissue growth. The term comes from Ancient Greek words meaning "new formation."
This process, called neoplasia, occurs when tissue grows in an uncoordinated way. It does not follow the normal patterns of the surrounding healthy tissue. Even if the original trigger for the growth is removed, the neoplasm continues to grow abnormally. These growths often form a mass, which is frequently called a tumor.
While the words are often used as synonyms, a tumor can be a solid or fluid-filled cystic lesion. A mass is a term used when a lesion is at least 20 mm in diameter. A nodule is a term for a lesion smaller than 20 mm.
Neoplasms are classified into four main groups by the ICD-10 system. The first group is benign neoplasms, which are non-cancerous. These are circumscribed and localized, meaning they stay in one place. Examples include uterine fibroids, osteophytes, and melanocytic nevi, which are skin moles.
The second group is in situ neoplasms, such as carcinoma in situ. These are localized and do not invade or destroy nearby tissue, but they may transform into cancer over time. The third group is malignant neoplasms, which are commonly known as cancers. These invade and destroy surrounding tissue and may form metastases. If left untreated, malignant neoplasms are generally fatal. The fourth group includes neoplasms of uncertain or unknown behavior.
Many neoplasms are monoclonal, meaning they originate from a single cell. This single population of cells carries the same genetic or epigenetic anomaly. This characteristic is known as clonality. In lymphoid neoplasms, such as lymphoma or leukemia, scientists prove clonality through specific tests. For B cell lesions, they look for the amplification of a single immunoglobulin gene rearrangement. For T cell lesions, they examine the T cell receptor gene. Proving clonality is now a necessary step to identify a lymphoid cell proliferation as neoplastic.
Tumors occur because of accumulated genetic and epigenetic alterations within single cells. These changes cause cells to divide and expand uncontrollably. DNA damage is the primary cause of malignant neoplasms. On average, a single human cell experiences more than 10,000 new damages every day due to cellular metabolism. External factors can increase this rate. Tobacco smoke increases DNA damage, which is a likely cause of lung cancer. UV light from solar radiation causes damage that contributes to melanoma. The infection Helicobacter pylori produces reactive oxygen species that damage DNA, contributing to gastric cancer.
Scientists also study the mechanics of how these growths expand. Vascular tumors, like hemangiomas or lymphangiomas, are made of blood or lymph vessels. Researchers model these as an amalgam of a solid skeleton of sticky cells and an organic liquid. This liquid fills the spaces where cells grow. Studies using this model show that active growth is often restricted to the outer edges of the tumor. They also found that the stiffening of underlying normal tissue can inhibit tumor growth.
Most malignant neoplasms are "sporadic cancers," meaning they have no hereditary component. About 70% of cancers fall into this category. While many sporadic cancers do not have a mutation in a DNA repair gene, many have epigenetic alterations. Epigenetic alterations can silence the expression of genes that are supposed to repair DNA. For example, in many colorectal cancers, the MGMT gene is not mutated but is silenced by methylation. This methylation of the MGMT promoter region reduces the gene's expression. When DNA repair gene expression is reduced, DNA damages accumulate at much higher levels.
This accumulation of damage leads to increased frequencies of mutation. These mutations and epigenetic alterations can create "field defects." A field defect is a patch of normal-appearing tissue that already contains multiple alterations. These defects serve as precursors to the disordered growth seen in malignant neoplasms. Once a cancer is established, it often possesses genome instability. This instability allows the cancer to continue evolving and producing sub-clones within the tumor.
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