A hypoechoic mass is not a medical condition but rather the appearance of dense tissue during an ultrasound. While this mass may be indicative of a cancerous tumor, it may also be a cyst or a harmless overgrowth of tissue. As such, the treatment of this mass is completely reliant on its specific cause.

The comparative nature of diagnostic ultrasound testing is particularly useful for discovering a hypoechoic mass in soft tissue. As a result, the majority of these masses are found in breast tissue. Causes of these dark areas include cysts, benign fibroadenomas, or cancerous growths.

The discovery of a hypoechoic mass in breast tissue is normally followed by a microscopic examination of the cells within the lump. When possible, cells are removed by inserting a needle into the area and drawing the sample into an attached syringe. The presence of clear fluid generally indicates a cyst; lack of this fluid points to a solid tumor. If the lump cannot be successfully tested using this method, a surgical procedure, called a biopsy, will be preformed to remove and test of a portion of the growth. If the growth is small, it may be entirely removed during the operation.

Usually, a hypoechoic mass caused by a breast cyst will require no further treatment. If the cyst becomes painful, however, draining by needle aspiration or surgical removal of the cyst may be necessary. Reoccurring or multiple cysts may be prevented with oral contraceptives.

Most commonly, a solid tumor in the breast is the result of an overgrowth of glandular tissue. These harmless growths can occur as tumors called adenomas in many areas of the body, but they are frequently referred to as fibroadenomas when they affect the breast. Like a breast cyst, this type of hypoechoic mass rarely requires medical intervention. Surgical removal of the adenoma may be done for aesthetic reasons.

When cancerous cells are found within a hypoechoic mass, surgical removal of the tumor is often required. As most cancer cells lack the ability to repair themselves, cell-destroying therapies such as radiation and chemotherapy may be prescribed. Radiation therapy is often preferred in early-stage cancers because the side effects are much more tolerable than chemotherapy. In late-stage or radiation-resistant cancers, systematic chemotherapy is frequently recommended.

Although hypoechoic masses are most commonly diagnosed in the breast, diagnostic ultrasounds can discover these growths in other parts of the body. Most frequently, these growths are benign adenomas that require medical intervention only if they become so large as to interfere with surrounding organs. The treatment of a cancerous growth is much the same regardless of tumor location.