A mass is a type of abnormal growth of tissue. Masses generally provide no useful function and grow at the expense of healthy tissues. Masses are also sometimes considered to be tumors. Tumors are classified as either benign (slow-growing and often harmless depending on the location) or malignant (faster-growing and likely to spread to other parts of the body and cause problems). Malignant tumors are what we call cancer.

Abnormalities of the immune system, which usually detects and blocks aberrant growth, can sometimes lead to tumors. Other causes include radiation, genetic abnormalities, certain viruses, sunlight, tobacco, benzene, certain poisonous mushrooms, and aflatoxins (a poison produced by an organism which sometimes grows on peanut plants). Tobacco causes more deaths from cancer than any other environmental agent.

What Are the Symptoms of a Mass?

Symptoms of a mass or tumor usually depend on its type and location. For example, lung tumors can cause coughing, shortness of breath, or chest pain while tumors of the colon can cause weight loss, diarrhea, constipation and blood in the stool. Some tumors produce no symptoms, but symptoms that often accompany tumors include: fevers, chills, night sweats, weight loss, loss of appetite, fatigue, and malaise.

Like the symptoms, the signs of tumors vary based on their site and type. When a tumor is found, a biopsy is sometimes performed to determine if the tumor is benign or malignant. Depending on the location and size of the tumor, the biopsy may be a simple procedure or a serious operation. Some patients with tumors undergo CT scans or MRI to determine the exact location of the tumor and its extent. More recently, positron emission tomography (PET) scans have been used to visualize tumors, especially those of a malignant nature.

How is a Mass Treated?

Treatment of masses or tumors also varies based upon their type, whether they are benign or malignant, and their location. If the tumor is benign (meaning it has no potential to spread) and is located in a "safe" area where it will not cause symptoms or disturb the proper functioning of the organ, sometimes no treatment is needed. Sometimes benign tumors may be removed for cosmetic reasons, or because they are located in a location that is bothersome to the patient (such as under a bra strap or waistband).

If the tumor is malignant and confined to one location, the goal of treatment is usually surgical removal of the tumor. If the tumor has spread to local lymph nodes only, sometimes these can also be removed.