September 25, 2025 Author : Cátia Ribeiro (general surgery) Breast diseases encompass a wide variety of conditions that can affect breast tissue, ranging from benign lesions to malignancies (cancer). Understanding them is essential for early diagnosis, appropriate monitoring, and treatment (when necessary) to achieve the best clinical outcome. Breast diseases can be divided into two major clinical groups: Benign Malignant Benign breast diseases Benign breast conditions are very common, representing about 80% of breast lesions identified in clinical or imaging exams. This means that for every 10 alterations detected, 8 are benign in origin, which is important for reassuring patients and guiding medical follow-up. Among these benign conditions, the following stand out: Fibroadenomas These benign tumors represent approximately 25% of benign lesions; They occur especially in women between 20 and 30 years of age; They are characterized by well-defined, painless masses; In rare cases, some fibroadenomas may present atypical characteristics or accelerated growth. This is the case with phyllodes tumors and giant fibroadenomas, which require specialized investigation and, sometimes, surgery. Breast cysts Cystic changes can range from small, painless formations to painful lesions, often associated with hormonal fluctuations. They are formed by fluid-filled cavities and can be divided into simple and complex cysts. Simple cysts Simple breast cysts have thin walls, homogeneous contents, and are painless. They generally do not have suspicious features on imaging tests. Simple cysts generally require only observation and monitoring, as they have a low risks of malignancy. If they are symptomatic or large in volume, aspiration of the fluid content is usually sufficient to relieve symptoms. Complex cysts Complex breast cysts have thicker walls, septa, calcifications, or heterogeneous contents. These factors may raise suspicion of a more serious change. In these cases, a biopsy may be necessary to categorize the lesion. Complex or suspicious cysts may require biopsy for further investigation and, in rare cases, surgical intervention if a neoplasia (malignant) is suspected or if the patient presents with persistent symptoms. Ductal and lobular hyperplasia Ductal and lobular hyperplasia are benign cell proliferations that, while not cancerous, require monitoring due to the increased risk of developing into malignancy. Mastitis and abscesses Mastitis and abscesses are inflammatory processes, often related to breastfeeding, that can cause pain, redness, and breast enlargement. Malignant breast pathologies Breast cancer is a well-known reality for the Portuguese population. About 7,000 women were affected in 2020, causing at least 1,800 deaths. The successful treatment of this condition is significantly linked to its early diagnosis. Early-stage cancer treatment has high cure rates, significantly reducing mortality. A physical examination and screening mammogram are essential for early diagnosis. Screening is recommended for asymptomatic patients, and the most important exam is a mammogram. It is a painless and simple exam that provides important information for diagnosis. The Breast Cancer Screening Program has been implemented in Portugal, providing easy and timely access to mammography for early diagnosis. The Direção Geral de Saúde updated its recommendations for breast cancer screening in December 2024. Women between 45 and 74 years of age are eligible. If the screening result is negative, screening should be repeated every 2 years. Breast cancer is a pathology that encompasses several types. The most common types include: Invasive ductal carcinoma : accounts for approximately 80% of cases, originating in the milk ducts of the breast and can infiltrate adjacent tissues. Invasive lobular carcinoma : develops in the breast lobes, often has diffuse growth and is difficult to detect in the early stages. Non-invasive carcinomas (ductal or lobular in situ) : precursor lesions with the potential to develop into invasive cancer. Other types : for example, tubular, mucinous, medullary, and inflammatory carcinomas, which have varying characteristics and prognoses. Risk factors Breast cancer has recognized risk factors and is associated with the Western lifestyle. However, the main risk factors are considered non-modifiable, such as gender and age. Known risk factors are: Being female (most important risk factor); Age; Personal and family history of breast cancer; Genetic alterations; Early menarche and late menopause; Nulliparity; Age at first pregnancy after 31 years of age; Use of hormone replacement therapy; Obesity; Sedentary lifestyle; Alcohol consumption; Smoking. Only 5% to 10% of diagnosed breast cancers appear to have genetic and hereditary characteristics. Prevention Primary prevention involves adopting healthy lifestyle habits, such as a balanced diet, regular exercise, weight control, and reduced alcohol consumption. Performing screening at the recommended ages, as well as periodic breast self-examination, combined with clinical and imaging exams whenever indicated, helps in the early detection of suspicious changes. Assessing genetic risk factors is also crucial for implementing more intensive surveillance strategies. Diagnosis A proper diagnosis is based on a combination of clinical history, physical examination, imaging tests (mammography, breast ultrasound, and MRI), and, when indicated, histopathological biopsies. Biopsies are essential for diagnostic confirmation and classify lesions according to their malignant potential. Treatment Benign pathologies often require clinical observation or surgical intervention, highlighting the importance of periodic follow-up. For malignancies , treatment involves a multidisciplinary approach, including surgery, radiotherapy, chemotherapy, hormone therapy, and targeted therapies. Documented scientific advances in this area have led to better results, both in terms of efficacy and patient quality of life. Meet the general surgery clinical team from Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
