Atlas of Anatomic Pathology with Imaging

The prime task of anatomic pathology (autopsy pathology and surgical pathology) is to identify structural (morphologic) abnormalities—both gross and microscopic—to relate these to functional disturbances and thus to identify diseases or disease combinations (“syndromes”). The requirement for such a “functional morphology” is a solid knowledge of the normal anatomy of organs and tissues, as well as physiologic and biochemical reaction patterns and their alterations in disease. The following basic principles need to be considered in anatomic pathology: (a) The development of morphologic lesions (i.e., “morphogenesis”) is time and dose dependent; that is, physiologic and chemical alterations require a certain duration and intensity to produce visible changes. (b) Morphologic lesions are most typical at the center of the pathologic insult, with less typical changes toward the periphery; in addition, secondary reactions (e.g., inflammation) may add to the picture of alterations in the periphery. However, if the central lesion consists of tissue necrosis (death of tissue), only the combination of central and peripheral lesions may allow the correct diagnosis. (c) Despite the large number of various pathogenic insults, the living organism has only a limited number of basic morphologic patterns in use to react to or fend off an insult. Such patterns consist of dystrophy and atrophy, apoptosis and necrosis, inflammation and immune reactions, hypertrophy and hyperplasia, and dysplasia, atypia, and neoplasia. To reach the final and conclusive diagnosis of a patient’s ailment, any pathologic findings must be interpreted in the context of other physical and biochemical data (i.e., “clinicopathologic correlation”).

Diseases of the heart and blood vessels constitute a leading cause of morbidity and mortality throughout the world. Most cases arise from complications of atherosclerosis, hypertension, and diabetes mellitus, but other forms of cardiovascular disease also are common.

This chapter discusses six common entities of respiratory disease: obstructive and restrictive disorders of gas exchange, infectious and inflammatory diseases, immunologic disorders, vascular diseases of the lung, tumors of the lung and pleura, and miscellaneous other diseases of the respiratory tract.

This chapter presents representative photographs of common diseases in the esophagus, stomach, small and large intestines, appendix, and rectum. Most of the diseases discussed here are infectious or neoplastic; a few others appear that students should be able to identify. A few microscopic photographs are added to support the understanding of gross lesions.

The liver is the largest solid visceral organ in the body and the most important “chemical factory,” with functions that cannot be replaced by any artificial means. Functions of the liver can essentially be divided into three major groups: synthetic, metabolic, and exocrine. The liver is the key organ in the metabolism of nutrients (glycogens, proteins, fats) and of exogenous chemical materials (drugs, toxins). It has enormous compensatory capacity and regenerative ability. Damage to the liver may not be detected until the late stage, and it is practically impossible for the anatomic pathologist to state exactly how much of the liver parenchyma must be destroyed before liver failure occurs. Massive destruction of the liver parenchyma or severe disorganization of its normal architecture may ultimately lead to hepatic failure. In fulminant liver failure, liver transplantation is by far the only rescue.

The genitourinary system consists of the two kidneys, two ureters, urinary bladder, and male and female genital organs. This chapter covers the urinary system and the male genital tract.

This chapter presents various diseases of the female sex organs, including the vulva, vagina, uterus and adnexa (ovary and salpinges), placenta, and breast. Discussed are common diseases, including congenital abnormalities, infection and inflammation, diseases related to endocrine disorders and to pregnancy, and both benign and malignant tumors.

This chapter discusses gross lesions of the hematopoietic and lymphatic systems (HLS), which are discussed together because they are derived from the same stem cell population. Both also serve similar functions, providing tools for host defense and maintaining internal homeostasis and bodily intactness. Such diverse functions determine a variety of delicate stages of cellular differentiation in the HLS; consequently, a multiplicity of functional disorders and diseases may arise. The number of typical gross lesions is rather limited, however, and a final classification of diseases must rely on detailed microscopic studies in combination with immunologic cell typing and molecular techniques. This chapter focuses only on gross pathologic features as a starter (including some representative radiologic images). The student is advised to supplement the studies of gross anatomy by consulting textbooks of hematopathology.

This chapter focuses primarily on diseases that are seen in a classic department of orthopedics. It does not include acute traumatic diseases (e.g., fractures) more common in a trauma center.

The skin, a large and complex organ, is exposed to more damaging agents than any other tissue. It therefore exhibits a very wide range of inflammatory disease patterns and reactions to infectious agents, as well as a large number of tumors. The breadth of dermatopathology is consequently immense, and a knowledge of dermatopathology in correlation to the clinical details of dermatology is a necessary prerequisite for definite diagnosis. This chapter provides a simple outline of the important patterns of inflammatory and infectious dermatoses and describes some important and common tumors that occur in the skin.

This chapter presents representative images of common diseases of the major endocrine organs. Some of these disorders are also described in other chapters, including the chapters on the genital tract, the central nervous system (pituitary), the gastrointestinal and respiratory systems (carcinoids), and the lymphatic tissues (thymus). Most disorders of the endocrine system become evident clinically on the basis of hypersecretion of hormones (hyperfunction), hyposecretion of hormones (hypofunction), or the presence of mass lesions, which may be evident on physical examination or radiologic studies. Hyperfunction is generally associated with hyperplasia or benign or malignant tumors, whereas hypofunction is generally associated with atrophy of the affected endocrine gland or with various destructive lesions that impair endocrine function. Some endocrine disorders have an infectious origin; others are the result of autoimmune mechanisms. In some instances, autoimmunity may underlie the development of hyperfunctional states, such as Graves’ disease, or hypofunctional states, such as Hashimoto’s disease.

This chapter discusses common anatomic features of diseases of the ear, nose, and throat, covering separately the individual regions of the ear; the oral cavity and salivary glands; the nose and paranasal sinuses; the nasopharynx, oropharynx, hypopharynx, and esophagus; the larynx and trachea, and the neck. Because of space limitations, only key changes can be outlined, and the reader is referred for further information to major textbooks.

Caries is an infectious disease (Streptococcus mutans, Lactobacillus, Actinomyces, etc.) that causes demineralization of hard dental tissues (enamel, dentin, and cementum). Four factors are necessary for the formation of caries: a tooth surface, bacteria in a biofilm called plaque, carbohydrates, and time. Under healthy oral conditions, there is a balance between demineralization through plaque and remineralization through saliva or fluoridated toothpaste. Poor oral hygiene or excessive consumption of sugar or acidic foods will shift this balance. In addition, some diseases (especially autoimmune connective tissue disorders) and medications (tricyclic antidepressants, antihypertensive agents, antiallergy drugs, etc.) predispose patients to develop caries because the flow of saliva is reduced.

Not too long ago, neuropathology was a subspecialty based mostly in academic centers, not anymore. With the advent of MRI, brain lesions are discovered early in their development, and the need for diagnostic biopsies has increased exponentially. On the other hand, the aging of the world populations makes familiarization with neurodegenerative diseases imperative.

Ophthalmic pathology focuses on specific elements of the eye, such as the conjunctiva, cornea, uvea, lens, retina, and optic nerve. The types of diseases resemble those of other organs, including congenital, degenerative and atrophic, inflammatory and immunologic, and hyperplastic and neoplastic diseases.