Adenocarcinoma of the breast is a term encompassing several types of tumors such as ductal and lobular carcinomas. An asymptomatic painless mass is usually the only symptom in the early stages, whereas an array of constitutional and localized symptoms may be seen in more advanced disease. Mammography and other imaging studies, such as magnetic resonance imaging (MRI) and ultrasonography, together with biopsy, are used to make the diagnosis.
With almost 250,000 new cases in the United states and about 1,380,000 new cases throughout the world, breast cancer is the most common female malignancy, but it is also one of the most lethal tumors (almost 41,000 deaths estimated in the US in 2016) [1] [2]. Countries of the developing world exhibit a much higher mortality rate compared to the Western world, primarily because of a delayed diagnosis and late initiation of treatment [2] [3] [4] [5]. Studies have identified that between 3-8 months may pass from the onset of symptoms to the diagnosis in the developing world, compared to 30-48 days in Western countries [4]. As the majority of breast cancer tumors start as glandular tumors (adenocarcinomas), the term adenocarcinoma of the breast can be used to describe two main types of tumors - lobular and ductal carcinomas [6]. Numerous risk factors have been evaluated in the pathogenesis of breast cancer, but exposure to ionizing radiation, use of exogenous ovarian hormones, and excessive alcohol consumption have emerged as the most important ones [3] [7]. The main symptom of breast cancer is the presence of a lump in the breast, which may be accompanied by edema (either locally or in the armpit, suggesting dissemination of the tumor into the proximal lymph nodes) [6]. In addition, localized pain, inversion or retraction of the nipple, breast tenderness and discomfort are reported [6]. Constitutional complaints (fatigue, malaise, weakness) and distant pain (suggesting metastatic spread) are seen in more advanced stages of the disease [8].
A detailed patient history and a complete physical examination are considered to be essential steps in the initial workup of breast cancer patients. During the patient interview, physicians should obtain key information about the onset and progression of symptoms and assess whether any of the mentioned risk factors (exposure to ionizing radiation, previous biopsies of the breast, use of oral contraceptives or post-menopausal hormonal supplements, and alcohol consumption are present [3]. A thorough family history, which may identify breast cancer or a history of other malignancies within the family, is also important [3]. The physical examination, however, is essential. A full inspection and palpation of both breasts is necessary in order to confirm the exact site of the mass, exclude enlargement of axillary lymph nodes, and evaluate the appearance of both the nipples (discharge, or anatomical changes such as inversion or retraction) and the surrounding skin (peau d'orange is a highly specific finding in advanced breast cancer where the skin resembles an orange peel) [3] [6]. Once a presumptive diagnosis is made based on clinical findings, imaging studies should be employed. Mammography is by many authors still regarded as the principal method for detection of lesions in the breast, and its use is indicated in all women who present with a palpable mass on physical examination [3] [9]. Additional procedures that can be used are magnetic resonance imaging (MRI) and ultrasonography, both used to assess the exact size and determine the tumor stage [3] [9] [10]. To determine the exact type of the tumor, a biopsy (either fine needle, core needle or excisional) is necessary [9] [11].