Molecular Biomarkers for Breast Cancer Prognosis

Introduction A diagnosis of invasive breast carcinoma, usually made by mammography with pathologic assessment of a needle core biopsy, requires a series of decisions related to selection of most appropriate therapy. These decisions involve an assessment of traditional prognostic factors such as tumor size, grade, involvement of axillary lymph nodes by metastases, and breast cancer biomarker status including estrogen receptor-alpha (ER), progesterone receptor (PR), and human…

Clinical Prognosis and Staging of Breast Cancer

Introduction An estimated 281,550 women were diagnosed with invasive breast cancer and 49,290 women were diagnosed with in situ cancer in 2021 in the United States. One in eight women are expected to be diagnosed with breast cancer as compared to one in 833 men. It is estimated that 43,600 women in the United States succumbed to breast cancer in 2021. The overall mortality rate has…

Unusual and Rare Tumors of the Breast

Introduction The rare tumors of the breast are a heterogeneous group of typically triple-negative tumors. With some notable exceptions, these tumors are low grade and are relatively indolent despite their triple-negative status and frequent basal phenotype. These tumors can be divided into those with putative salivary gland analogs and those without. The nonsalivary gland type tumors include acinic cell carcinoma (ACC), tall cell carcinoma with reversed…

Mesenchymal Neoplasms of the Breast

Vascular Tumors Angiosarcoma Angiosarcomas (AS) are the most common sarcomas encountered in the breast. They account for <1% of all breast malignancies. They are divided into two categories: primary AS (idiopathic) and secondary AS. Secondary AS most often occur following radiation therapy, but they can also be associated with chronic lymphedema (Stewart-Treves syndrome). Primary AS typically occur in younger women aged 15 to 74 years (mean…

Lymphomas of the Breast

Definition and Epidemiology Malignant lymphoma arises within lymph nodes or develops outside of nodal tissues (extranodal). Primary extranodal presentation of lymphoma occurs in 20% to 30% of cases and involvement of the breast is uncommon. The diagnosis of primary breast lymphomas (PBL) requires fulfillment of three criteria: the lymphomatous infiltrate is closely associated with mammary tissue, an adequate histopathologic evaluation is performed, and systemic or antecedent…

Fibroepithelial Tumors and Hamartomas

Introduction Fibroepithelial lesions of the breast are biphasic neoplasms comprised of variable amounts of stroma and benign epithelial elements. This spectrum of entities includes fibroadenomas and phyllodes tumors. Hamartomas are composed of the lobular glands of normal breast tissue set within a circumscribed, often encapsulated-appearing, fibroadipose tissue mass. Given the resemblance of hamartomas to fibroepithelial lesions, they are discussed together in this chapter. Fibroepithelial lesions and…

Biomarkers

Introduction Breast cancer is a heterogeneous disease process. The World Health Organization recognizes many morphologic subtypes. By gene expression, invasive breast cancer is classified into at least four major subtypes: luminal A, luminal B, human epidermal growth factor receptor 2 (HER2)-positive, and triple-negative (ER/PR- and HER2-negative). The biology and the prognosis of these subtypes are vastly different. Genetic profiles of these cancer subtypes are also interlinked…

Infiltrating Carcinomas of the Breast

Introduction Breast cancer is the leading cause of cancer death in women worldwide (15.5%). It is also the leading cause of cancer in women worldwide (24.5%). An estimated 276,480 women developed breast cancer in 2020. The estimated mortality is 42,170. The etiology of breast cancer is multifactorial. In a screened population approximately 70% of cancers are hormone receptor (HR) (estrogen receptor [ER] and progesterone receptor [PR])-positive.…

Ductal Carcinoma In Situ

Introduction Over the past several decades, the widespread adoption of mammographic screening has had a significant impact on the incidence, diagnosis, classification, and treatment of ductal carcinoma in situ (DCIS). There has been a vast increase in the publications with regard to the definition, diagnostic criteria, and both short-term and long-term risks associated with specific histologic variants or types of in situ carcinoma of the breast.…

Disorders of the Skin

Introduction The breast is surfaced by skin, which can be affected by numerous conditions, both inflammatory and neoplastic. Some of these entities are specific to the breast skin, while other entities may diffusely involve the skin, including the skin of the breast. This chapter will attempt to concisely characterize some of the most common dermatologic conditions, benign and malignant, affecting the breast. Inflammatory Disorders Dermatitis Eczematous…

High-Risk and Premalignant Lesions of the Breast

Introduction Some breast lesions have been termed “high risk” for either (1) an immediate risk of breast cancer due to underdiagnosis by percutaneous biopsy or (2) a long-term increased risk of future breast cancer (hence the term “premalignant”). The classical lesions in this group are atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and lobular carcinoma in situ (LCIS). For decades, these lesions have been recognized…

Gynecomastia

Gynecomastia is a benign enlargement of the male breast due to proliferation of the glandular component. This common clinical condition, which may be unilateral or bilateral, presents as an incidental finding on routine physical examination, a painless unilateral or bilateral breast enlargement, or a painful and tender mass beneath the areolar region. This chapter focuses on the prevalence, clinical presentation, physiology, histopathology, pathophysiology, diagnosis, and treatment…

Mastitis and Breast Abscess

Management of patients with a breast abscess is an art, and each abscess has unique features that require familiarity by the treating physician. Breast abscesses can be frustrating for both the patient and the surgeon. Even for patients referred with chronic, recurring abscesses, the surgeon should initially repeat the breast conservative treatment that may have failed in the past, the purpose of which is to “get…

Etiology and Management of Benign Breast Disease

The aberrations of normal development and involution (ANDI) classification of benign breast disorder (BBD) provides an overall framework for benign conditions of the breast that encompasses both pathogenesis and the degree of abnormality. It is a bidirectional framework based on the fact that most BBDs arise from normal physiologic processes ( Table 14.1 ). The horizontal component defines BBD along a spectrum from normal to mild…

Breast Cancer Diagnosis and Techniques for Biopsy

In the United States, breast cancer is the most commonly diagnosed cancer in women (excluding skin cancer), and it is also the second leading cause of cancer death among women in the United States. Routine screening mammography has been proven to decrease breast cancer mortality, as noted in a 2020 study which found that performing screening mammography in women aged 40 to 49 years reduced mortality…

Breast Cancer Screening

The aim of screening is to improve survival by early detection of disease. Detection of early-stage disease in asymptomatic patients has the potential to improve outcomes by providing more effective treatment. Screening tests are not considered diagnostic, but rather identify a subset of the population that should undergo additional diagnostic tests to determine the presence or absence of disease. For a screening program to be effective,…

Clinical Encounter With the Patient

Breast disease encompasses a variety of benign and malignant disorders. Although fortunately the majority of breast complaints are ultimately benign, breast cancer is the most common cause of cancer and the second leading cause of cancer-related deaths among women in the United States. In 2021 an estimated 281,550 new cases of invasive breast cancer were expected to be diagnosed among US women, along with 49,290 new…

Breast Cancer Genetics: Syndromes, Genes, Pathology, Counseling, Testing, and Treatment

Introduction Soon after the French revolution (1789–99) Paris hosted the birth of modern scientific medicine. Prominent clinician-scientists working to understand the origins of human cancer collected cancer family histories and debated whether family cancer clusters proved that cancer was contagious or rather, was somehow transmitted from parent to offspring. Writing in 1851, the pioneer of modern diagnostic pathology, Hermann Lebert, suggested that “…children come into the…

Risk Reduction for Developing Breast Cancer

Identifying Women at Risk Chemoprevention can be defined as the use of natural or synthetic chemical agents to reverse, suppress, or prevent carcinogenic progression to invasive cancer. Epidemiologic data suggesting that breast cancer is preventable through drug intervention include time trends in cancer incidence and mortality, geographic variations and the effects of migration, identification of specific causative factors, and the observation that most human cancers do…

Carcinogenesis of Breast Cancer

Introduction The oldest documented case of human cancer dates back to 3000 BCE in ancient Egypt. The details were recorded on papyrus, and described a case involving a tumor of the breast. At the time, these tumors were believed to be incurable and “the curse of the Gods,” and this ideology persisted for thousands of years. Approximately 460 to 370 BCE, a Greek physician named Hippocrates…