What is a tumor? These abnormal growths may affect organs, bones, glands and tissues. No part of the body is safe from tumor development, but not all tumors are life-threatening.

What Is a Tumor?

The National Cancer Institute defines a tumor as, “An abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should.” This solid mass contains millions of cells —many of which are an abnormal shape. These cells also have abnormal DNA and chromosomes.

How Do Tumors Form?

The body is always making new cells to replace old or damaged ones. In the natural course of things, damaged cells die off and are replaced by healthy cells.

Sometimes, cells don’t die off as they should. In other instances, new cells grow and multiply faster than expected. Tumors form when these cells collect and become a mass.

Factors in Tumor Development

Anyone, at any age, may develop a tumor. However, there are certain risk factors that make tumor development more likely. These include:

  • Certain gene mutations such as BRCA-1 and BRCA-2 genes for breast and ovarian cancer
  • Family history of some cancer types
  • Smoking
  • Excessive alcohol consumption
  • Toxin exposure
  • Radiation
  • Obesity
  • Immune disorders
  • Too much sun exposure

Some tumors result from viruses. Cervical cancer and most anal cancers result from infection with the human papillomavirus. The same holds for many genital tumors — both male and female. Some liver cancers are caused by hepatitis B or C infections.

Benign and Malignant Tumors

Tumors are either benign or malignant. Benign tumors are non-cancerous that tend to grow slowly and do not spread to other tissues or areas of the body. Uterine fibroids are common benign tumors.

That is not the case with malignant cancerous tumors. These tumors may spread rapidly, destroying the tissues they invade.

Tumor Symptoms

Tumor symptoms may or may not prove obvious. Some people may feel a mass in the body. Many women discover lumps in their breasts that are later diagnosed as tumors. Always see your doctor right away if you notice any unusual lumps or growths on your body.

Tumors located more deeply within the body are not palpable. Tumor symptoms may include:

  • Pain
  • Unexplained weight loss
  • Fatigue
  • Appetite loss
  • Fever
  • Chills
  • Night sweats

Detecting Tumors

When it comes to tumors, an early diagnosis often makes all the difference in the outcome. If a cancerous tumor is detected before it has a chance to spread (metastasize) treatment can save the life of the patient.

Screening tests are initially used to detect tumors. These include:

  • X-rays
  • Ultrasounds
  • Computed tomography scans
  • Magnetic resonance imaging

After a tumor is identified on an imaging test, doctors take blood and urine samples to measure hormone and chemical levels. These samples are sent to pathologists for diagnosis.

The doctor conducts a biopsy to obtain a tissue sample of the growth. These biopsy samples are sent to pathologists who examine them under a microscope to detect cancer. The pathology report details the cancer type, whether it has spread and the grade. The latter refer to how the tumor cells compare to healthy cells. Well differentiated cells resemble healthy cells which can mean a better prognosis. The report reveals the stage of the tumor based on size, location and whether it has spread. Tumor markers — such as hormone receptors — are also indicated in the pathology report.

Treatment depends on whether the tumor is benign or malignant, as well as the size, type and grade of the mass. Treatment options may include:

  • Surgical removal
  • Chemotherapy
  • Radiation
  • Immunotherapy

Even a benign tumor can require surgical removal. Although, the patient will not need to go through the other therapies designed to combat cancer.

Contact Us

At Yosemite Pathology and Precision Pathology, we are your efficient, quality-focused partner for patient care. For more than 70 years, we have advanced anatomic pathology in the Western United States. More than 20 board certified anatomic pathology specialists are currently part of our practice. Our expertise in anatomic pathology covers not only basic surgical pathology and cytology, but also extends to a variety of subspecialties. We offer a broad range of specialties, including breast, gynecologic, hematology, thyroid, urologic and other pathologies. For more information about our services, contact us today.

Jane Meggitt’s work has appeared in dozens of publications including USA Today, Zack’s, Financial Advisor, nj.com, The Houston Chronicle and The Nest. She is a graduate of New York University.


National Cancer Institute – Tumor

Cleveland Clinic – Tumor: What Is It, Types, Symptoms, Treatment & Prevention (clevelandclinic.org)

MedlinePlus – Tumor