Breast cancer is overwhelmingly linked to hormonal changes and age, making it exceptionally rare in children and adolescents. When a lump is found in a young person’s breast area, it is almost always due to a benign or developmental cause. This article explains the statistics behind this rarity, details the common causes of breast masses in young people, and describes the specific types of rare malignancies that can occur.
How Rare is Pediatric Breast Cancer
Breast cancer accounts for less than one percent of all cancers diagnosed in children and adolescents. The incidence rate is extremely low, estimated at around 0.1 cases per 100,000 individuals under the age of 20. For teenagers between 15 and 19 years old, the incidence is approximately one in a million.
The low incidence occurs because the most common forms of adult breast cancer are driven by hormones like estrogen and progesterone. Pediatric breast tissue is still developing and is not typically exposed to the long-term hormonal stimulation seen in adults, which is a major factor in typical breast cancer development. The few malignancies that appear in this age group are often biologically different from the invasive ductal carcinoma seen in older adults.
Common Causes of Breast Lumps in Young People
Nearly all breast masses found in children and adolescents are benign growths related to normal pubertal development. The most frequent cause of a palpable lump in an adolescent girl is a fibroadenoma, an overgrowth of glandular and connective tissue. These masses are typically smooth, firm, rubbery, and easily moveable beneath the skin, accounting for approximately 95% of all breast lesions in adolescents.
In younger girls, premature thelarche is a common finding, involving the early development of breast buds. This developmental process presents as a small, firm, and sometimes tender lump beneath the nipple. The appearance of breast buds is a normal physiological stage.
Breast cysts, which are simple fluid-filled sacs, can also occur, though they are more common in women approaching menopause. In young people, these cysts may fluctuate in size or tenderness with the menstrual cycle, but they are non-cancerous and do not increase the future risk of malignancy. For adolescent boys, a breast lump is most often due to gynecomastia, a temporary swelling of the breast tissue caused by normal hormonal shifts during puberty.
Malignant Tumors That Can Affect the Pediatric Breast
When a malignancy does occur, it is often a specific type that differs from the typical adult disease. The most frequently reported primary malignancy in the pediatric age group is Secretory Carcinoma, also known as juvenile breast carcinoma. This type is generally slow-growing and tends to have a more favorable outlook compared to most adult breast cancers.
Another category of concern is the Phyllodes tumor, which develops from the connective tissue within the breast. While the vast majority are benign, they can occasionally be borderline or malignant, and they tend to grow much faster than fibroadenomas. Sarcomas, which are cancers of the connective tissues, may also affect the breast area, including Rhabdomyosarcoma.
In some cases, a breast mass is a sign of metastatic disease, meaning the cancer originated elsewhere and spread to the breast tissue. Primary cancers like leukemia, neuroblastoma, or other soft tissue sarcomas can metastasize to the breast in children. This secondary spread is sometimes more common than a primary breast cancer diagnosis in this age group.
When to Seek Medical Attention and Diagnosis
Any new or changing lump in the breast area should be evaluated by a medical professional to ensure a proper diagnosis. Certain characteristics of a mass warrant more immediate attention and require prompt medical assessment:
- A lump that is rapidly increasing in size.
- A mass that feels hard and fixed, meaning it does not move freely under the skin.
- Skin changes like dimpling, puckering, or scaling.
- Any unusual nipple discharge, especially if it is bloody.
The diagnostic process begins with a physical examination, followed by imaging. Ultrasound is the primary tool for evaluating pediatric breast masses because it avoids radiation exposure and is effective for imaging dense breast tissue. If imaging reveals suspicious features, such as irregular margins or a size greater than three centimeters, a core needle biopsy may be necessary for a definitive diagnosis.