When an indentation, or “dent,” appears on the breast surface, especially when the arms are lifted, it is medically referred to as skin retraction, tethering, or dimpling. This symptom occurs because raising the arms stretches the skin and underlying tissues, making any area of localized tension more visible. While the appearance of a new change can cause concern, this visible pulling effect is a mechanical symptom that requires professional evaluation to determine its exact origin. The symptom itself is caused by a structural issue beneath the surface, which could be related to a variety of benign or malignant conditions.
The Anatomy Behind the Symptom
The physical structure that allows a dent to form is a network of connective tissues called Cooper’s ligaments, also known as the suspensory ligaments of the breast. These fibrous bands extend through the fatty and glandular tissue, connecting the deep fascia covering the chest muscle to the dermis layer of the skin. They provide internal support and maintain the breast’s shape.
When the arms are raised, the pectoralis muscles beneath the breast contract, pulling the skin taut and placing tension on the Cooper’s ligaments. If a mass or localized area of scar tissue has infiltrated or shortened these ligaments, the movement pulls the skin inward. This mechanical tethering creates the visible dimple or puckering, which often disappears when the arm is lowered. The simple maneuver of raising the arms is a physical examination technique specifically designed to unmask this underlying structural issue.
Benign Causes of Skin Dimpling
It is important to recognize that a dent in the breast is not always indicative of a serious condition, as several non-cancerous issues can cause localized tissue changes. One common benign cause is fat necrosis, a condition where fatty tissue becomes damaged and dies, often following trauma, surgery, or radiation therapy. The body attempts to repair this damaged area by replacing it with firm, hardened scar tissue.
This resulting scar tissue can contract and pull on the nearby Cooper’s ligaments, leading to visible skin dimpling. Fat necrosis may present as a firm, sometimes tender, lump with overlying dimpled or bruised skin. Previous surgical procedures, such as biopsies, lumpectomies, or cosmetic surgeries, can also result in internal scar tissue. In these cases, the localized retraction occurs as the tissue heals and contracts over time, and the pulling is a harmless consequence of the body’s healing process.
Malignant Causes and Associated Symptoms
The most significant cause of a dent in the breast is an underlying malignancy, particularly invasive breast cancer. A cancerous tumor that grows within the breast tissue can invade and shorten the Cooper’s ligaments, causing them to pull the skin inward. This specific type of tethering is a classic sign often seen in advanced tumors like Invasive Ductal Carcinoma.
In some aggressive cases, such as with Inflammatory Breast Cancer, the dimpling can present as a more widespread, pitted texture known as peau d’orange, or “orange peel” skin. This appearance is not caused by the tumor directly shortening the ligaments but by cancer cells blocking the lymphatic vessels in the skin, leading to fluid accumulation and swelling. This generalized edema causes the skin pores to become prominent, creating the pitted texture.
When a dimple is caused by cancer, it is frequently accompanied by other noticeable changes that act as warning signs. These associated symptoms include:
- A newly developed, fixed, and often painless lump beneath the skin.
- Nipple retraction or inversion that was not previously present.
- Persistent redness or swelling that covers a third or more of the breast.
- Unusual discharge from the nipple.
Recognizing these accompanying symptoms alongside skin dimpling is paramount for timely intervention.
Necessary Steps for Diagnosis
Any new or concerning change to the breast’s appearance, including skin dimpling, necessitates a prompt consultation with a healthcare provider. The diagnostic process begins with a thorough clinical breast examination, where the provider assesses the area and performs maneuvers like raising the arms to confirm the retraction. Imaging tests are then ordered to visualize the internal structure of the breast.
Initial imaging typically involves a diagnostic mammogram, often with specialized views to better capture the area of skin change, and a breast ultrasound to evaluate any detected masses as solid or fluid-filled. Depending on these findings, a Magnetic Resonance Imaging (MRI) scan may also be used to provide a detailed map of the breast tissue. If a suspicious mass is identified, a definitive diagnosis is secured through a biopsy, where a small tissue sample is removed using a fine needle or core needle under imaging guidance. The tissue is then analyzed by a pathologist to determine if the cause is benign scar tissue or a cancerous growth.