The epithelial system of the breast consists of a ductal system and terminal ductal lobular units, both of which are lined by two cell layers: an inner layer of luminal epithelial cells facing the lumen and an outer layer of myoepithelial cells that sit on the basement membrane. The epithelial system of the breast can give rise to a variety of benign and malignant lesions that…
The term radial scar (RS) was first coined in the 1980s in a German paper by Hamperl. Page and Anderson first suggested using the term radial scar for lesions measuring up to 9 mm and the term complex sclerosing lesion (CSL) for larger lesions. Sloane and Mayers used a 10-mm cutoff for RS and CSL for larger lesions. However, one of the earliest published reports described…
An uncommon variant of intraductal papilloma that involves the nipple, florid papillomatosis was first described as a clinicopathological entity in 1955 by Jones. Alternative terms used for this entity include nipple adenoma , erosive adenomatosis , superficial papillary adenomatosis , subareolar duct papillomatosis of the nipple , and papillary adenoma . Occasionally, the term syringomatous adenoma has been used in older literature but is not recommended…
Introduction The term adenosis is used to describe a non-neoplastic lobulocentric proliferation of ductules with epithelial and myoepithelial cells, usually formed from the terminal duct lobular unit. The clinical presentation is variable and numerous microscopic variants have been described. Most are benign. This chapter discusses adenosis and addresses the involvement of adenosis by other pathological entities. Microglandular adenosis (MGA) is described separately later in this chapter.…
Papillary lesions of the breast encompass a heterogeneous group of epithelial lesions ranging from benign to malignant, and represent one of the most challenging diagnostic entities in breast pathology, constituting 21% of pathologist-initiated second-opinion referrals. Although their exact incidence is difficult to determine with accuracy given variable terminologies used over time, papillomas account for 8% to 10% of benign breast lesions and the incidence of papillary…
Fibroepithelial tumors represent some of the more common tumors in women of all ages. This class of lesions is unique to the dual, synchronous, proliferative capacities of both epithelial and stromal elements. Benign lesions, known as fibroadenomas, are marked by the epithelial and stromal elements proliferating in unison, while phyllodes tumors display asynchronous growth of the epithelial and stromal elements. There are lesions with overlapping features…
Introduction For diagnosing a majority of breast lesions, a high-quality hematoxylin-eosin (H&E) stained section is all that is needed. However, in our quest for improved diagnostic accuracy, immunohistochemistry (IHC) is frequently used in diagnostic breast pathology. The sheer volume and genuine difficulty of some cases, even for breast experts, result in frequent use of IHC in day-to-day practice. This chapter addresses diagnostic issues involving stromal invasion,…
The emergence of high-throughput omics technologies in the mid-1990s heralded the emergence of a new paradigm of personalized medicine. Researchers could now study dynamic biological systems, including cancers, in novel and comprehensive ways. Collaborations arose among basic scientists, clinical researchers, bioinformaticians, and biostatisticians, resulting in the development of a multitude of omics-based tests for use in oncology. The speed of technological advancement and the ability to…
Introduction This chapter is divided into three main sections. The first two include discussion of well-known prognostic/predictive markers—namely, steroid hormone receptors (estrogen and progesterone) and one of the most well-studied oncogenes in breast cancer, human epidermal growth factor receptor 2 or HER2 (ERBB2). These sections are followed by a brief discussion of other relevant single-gene and gene products that are being increasingly assessed in breast cancer.…
The world of imaging continues to change thanks to advances in the field of breast imaging. Improvements in diagnosis, imaging, computer-assisted detection, surgical approach, therapy, and staging, to name a few, have contributed to the growth of this important field. As the body of knowledge for breast cancer diagnosis and treatment expands, it is increasingly important for the various specialties involved in the care of breast…
Systematic screening of women by mammography and clinical examination has resulted in early diagnosis of breast cancer and a 25% to 30% decrease in mortality. Early breast cancer can be cured with locoregional treatment alone in some cases. However, subclinical metastases do occur, and in a significant percentage of women treated with an apparently curative locoregional therapy, distant metastases ultimately develop. Trying to determine which women…
The subspecialty of breast pathology has grown in complexity as the needs of the end users of our reports have increased in complexity. More sensitive imaging techniques have allowed for identification of clinically and often grossly nonapparent lesions. New surgical techniques have also given rise to new types of breast specimens that use more sophisticated tissue-preserving techniques, such as nipple-sparing and skin-sparing mastectomies. Staging and clinical…
Despite the long-standing worldwide attention given to the fight against breast cancer, this disease remains a serious illness that affects the physical and emotional well-being of many individuals around the world. As a global public health problem, breast cancer is a heterogeneous disease with a rather unpredictable outcome, ranging from an indolent tumor to a rapidly progressive disease with the ability to claim the life of…
Introduction Breast cancer is the most common cancer in American women other than skin cancers. The average woman in the United States has a lifetime risk of developing breast cancer of about 13%. The American Cancer Society estimates that about 281,550 new cases of invasive breast cancer will be diagnosed in women during 2021, and there will be approximately 49,290 new cases of ductal carcinoma in…
Breast infection is uncommon in the United States, yet it still occurs, even in neonates. It usually affects women between 18 and 50 years of age. Breast infections in adults can be divided into two basic types: lactational and nonlactational infections. The breast infection can extend to the skin overlying the breast, or it may be secondary to a primary skin infection such as a ruptured…
Benign, reactive, and inflammatory tumorous conditions of the breast are the most common reasons patients undergo breast biopsies. Benign conditions account for the majority of breast biopsies, and reactive or inflammatory conditions comprise the majority of pathological findings in this category. Inflammation-related changes and reactive changes that mimic neoplasia are commonly seen in fibrocystic changes (FCC), which is discussed in Chapter 18 . The conditions discussed…
Normal Breast The breasts are the distinguishing feature of mammals. The word mammal is derived from mamma which is the Latin term for breast. The breasts have evolved as milk-producing organs to provide appropriate nourishment for offspring and other benefits of nursing. Physiologically, this act serves to help involute the uterus; and psychologically, it helps to bond the mother and the offspring. Finally, the epigamic value…
Introduction Bone is one of the most common anatomic sites for metastases, along with the lungs and liver, and metastases are the most commonly diagnosed neoplasms encountered in the skeleton. Metastases are far more frequent in bone than are primary bone neoplasms. Although carcinomas of all types account for most metastatic deposits in the adult skeleton, melanomas, sarcomas, and even germ cell tumors may also metastasize…
Fibrous Dysplasia Clinical Features Fibrous dysplasia is a benign proliferation of fibro-osseous tissue that may be diagnosed at any age; most manifest in the second to third decades of life ( Table 24.1 ). Males and females are affected equally, and it may occur in all racial groups. Most (70%–80%) are solitary (monostotic), but a minority of patients have multiple bone involvement (polyostotic). Although symptoms vary depending…
Introduction A variety of cystic lesions may arise within bone ( Table 23.1 ). Additionally, many neoplasms may undergo secondary cystic changes, and adequate tissue sampling is therefore essential ( Table 23.2 ). In this chapter, we will address the clinical, radiographic, and pathologic features of simple (solitary, unicameral) bone cyst, aneurysmal bone cyst, subchondral bone cyst, and ganglion cyst of bone. Table 23.1 Cysts of Bone Simple…