A tumor, or neoplasm, is abnormal tissue that develops because of excessive cell growth.
Illustration by Julie Bang for Verywell Health
When Is a Tumor Cancer?
All tumors are triggered by abnormal, often excessive, cell growth.
Illustration by Julie Bang for Verywell Health
This is part of a process known asmetastasis, and its what makes cancer so dangerous.
It’s typical for cancerous tumors break through the tissue from which they originate and invade other areas.
Benign tumorstypically grow more gradually and dont spread.
They can be benign, malignant, or precancerous.
A precancerous tumor could become malignant over time.
Other tumor markers are genetic mutations.
Certain mutations can affect any gene involved in cancer starting or progressing.
Characteristics and Symptoms
Some tumors cause few or no symptoms.
Others have telltale signs and characteristics.
The following are the typical appearance and sensations of common tumors, as well as how they form.
Appearance
You may not notice a tumor at all at first, especially if its internal.
You might also notice skin changes, whether its a bleeding lump or a scaly growth.
Sensation
Many benign tumors are asymptomatic (i.e., show no symptoms).
However, if they grow larger, they might press on surrounding body parts near the affected area.
Most cancers are associated with aging and appear after age 50.
There are many risk factors for developing a malignant tumor.
To make a definitive diagnosis, you may also be asked to undergo other tests.
Even after being removed by chemotherapy or surgery, some tumors may grow back.
When this happens with a malignant tumor, its known as cancer recurrence.
You may need further treatment(s) to remove the recurring tumor.
Summary
A tumor is an external or internal lump resulting from excessive cell growth.
Tumors can be cancerous (malignant), precancerous, or noncancerous (benign).
Other possible treatments for malignant tumors include chemotherapy, radiation therapy, immunotherapy, and targeted cancer medications.
American Cancer Society.What is cancer?
Patel A.Benign vs malignant tumors.JAMA Oncol.
2020;6(9):1488. doi:10.1001/jamaoncol.2020.2592
National Cancer Institute.Tumor list.
National Cancer Institute.Tumor markers.
Last updated: December 7, 2023.
National Cancer Institute.Tumor necrosis factor.
American Cancer Society.Oncogenes, tumor suppressor genes, and DNA repair genes.
American Cancer Society.Signs and symptoms of cancer.
Cancer Research UK.Age and cancer.
Cancer Research UK.Why some cancers come back.
