Neoplasm/Tumor
A neoplasm, commonly called a tumor, is an abnormal growth of tissue resulting from uncontrolled cell division. Neoplasms can be benign (non-cancerous) or malignant (cancerous) and can occur in virtually any tissue or organ in the body. While benign tumors grow slowly and remain localized without spreading, malignant tumors can invade surrounding tissues and metastasize to distant sites. Detection and characterization of neoplasms through imaging is crucial for determining appropriate treatment and prognosis.
What is it?
Neoplasms develop when normal cellular growth regulation mechanisms fail, leading to uncontrolled proliferation of cells. Normally, cells grow, divide, and die in an orderly fashion, with new cells replacing old or damaged ones. In neoplasms, this balance is disrupted—cells continue to divide when they shouldn’t, fail to die when they should, or both. This results in the accumulation of excess tissue forming a mass or tumor. Neoplasms are broadly classified as benign or malignant based on their behavior and cellular characteristics under microscopic examination.
Benign neoplasms are typically slow-growing, well-circumscribed masses that remain localized to their site of origin. They do not invade surrounding tissues or spread to distant sites, though they can still cause problems by compressing nearby structures or producing hormones. Examples include lipomas (fatty tumors), fibromas (fibrous tissue tumors), adenomas (glandular tumors), and many others. Malignant neoplasms, or cancers, are characterized by uncontrolled growth, ability to invade adjacent tissues, and potential to metastasize (spread) to distant organs through blood or lymphatic vessels. They are named based on their tissue of origin: carcinomas arise from epithelial cells (skin, organ linings), sarcomas from connective tissues (bone, muscle, fat), leukemias from blood-forming cells, and lymphomas from lymphatic system cells. Risk factors for developing neoplasms include genetic predisposition, environmental exposures (tobacco, radiation, certain chemicals), chronic inflammation, certain infections (HPV, hepatitis, H. pylori), and lifestyle factors such as diet, obesity, and physical inactivity.
Important to Know
Symptoms of neoplasms vary dramatically depending on their location, size, and whether they are benign or malignant. Some tumors cause no symptoms and are discovered incidentally during imaging for other reasons. Common symptoms that may indicate a neoplasm include a palpable lump or mass, unexplained pain, bleeding or discharge, persistent cough or hoarseness, changes in bowel or bladder habits, unexplained weight loss, fatigue, or symptoms related to compression of specific organs. Diagnosis typically involves imaging studies (CT, MRI, PET-CT, or ultrasound) to visualize the tumor and assess its characteristics, followed by biopsy to obtain tissue for pathological examination, which definitively determines whether the tumor is benign or malignant and identifies its specific type. Treatment depends on numerous factors including tumor type, location, size, grade, stage (for malignant tumors), and patient factors. Options include surgical removal (curative for many benign tumors and localized cancers), radiation therapy, chemotherapy, targeted molecular therapies, immunotherapy, or combinations of these approaches. For benign tumors, observation without treatment may be appropriate if they are not causing symptoms. Advances in precision medicine now allow many malignant tumors to be treated with therapies targeted to specific genetic mutations in the tumor cells. Early detection through screening programs and imaging significantly improves outcomes for many cancer types.