Department of Pathology

The Autopsy Division performs approximately 250 autopsies a year for a wide range of evaluations, including:

• Determine cause of death
• Confirm clinical diagnoses
• Evaluate the effects of therapy
• Study disease processes

The Autopsy Division strives for accuracy, completeness and timeliness in performing and reporting on autopsies. While the expertise and resources of the Feinberg School of Medicine and Northwestern Memorial Hospital are available for specialized consultations, the autopsy faculty has special expertise in areas that affect most patients, including:

• Cardiovascular disease
• Cancer
• Neuropathology
• Perinatal pathology

Cytopathology is a highly specialized branch of anatomic pathology that provides diagnoses of benign, precancerous and malignant lesions at the cellular level, using minimally invasive sampling methods. Board-certified cytopathologists, along with our cytotechnologists, trainees and laboratory staff, function as part of various multidisciplinary teams to provide patients with the highest standard of care. Cytopathology uses two major types of specimens, including:

• Fine needle aspiration biopsy (FNA): Like a blood draw, FNA is a minimally invasive way to obtain tissue from a mass lesion using a thin needle, with or without radiologic guidance. FNA is often accompanied by a core biopsy.
• Exfoliative cytology: Exfoliative cytology includes performing tests such as Pap tests and studies of body fluids, brushings and lavages, which use water or other solutions to extract cells. It involves procuring material for cancer screening, diagnostic purposes and staging, which determines the extent a tumor has spread.

Tissue obtained by the cytopathology laboratory may be used for specialized studies to provide specific diagnoses, prognostic information and eligibility for personalized drug therapy.

The Immunohistochemistry Division performs phenotypic studies, which help identify tumor cell types and give valuable information about potential treatment options and patient prognosis. These pathologists perform immunohistochemical staining, in situ hybridization and immunofluorescent staining on routinely processed paraffin-embedded tissue sections and on frozen tissue sections to determine to phenotype of individual cells and/or cell populations.

Surgical pathology provides the definitive diagnosis of disease in cases where tissue is surgically removed from a living patient. Two main types of surgical pathology specimens include:

• Biopsies
• Surgical resections

Biopsies are small pieces of tissue that fall into one of three categories:

• Core biopsies: Obtained through a large bore needle under ultrasound or imaging guidance
• Incisional biopsies: Removal of a small part of the suspicious lesion
• Excisional biopsies: Removal of the entire suspicious lesion

Surgical resection specimens are obtained by surgically removing the entire diseased organ or region, which may include several organs. The practice of surgical pathology is usually a combination of gross (visual or macroscopic) and microscopic examination of tissue, and may also involve leading-edge techniques or state-of-the-art molecular and genetic laboratory tests to evaluate the properties of the tissue and disease.

Surgical pathology analysis of these biopsy and surgical resection specimens is the gold standard to confirm a diagnosis and stage the extent of malignant disease. The other major function of the surgical pathology division is to perform rapid intraoperative consultations (frozen sections) to assist surgeons in charting the proper course during surgical procedures.

Examination of the fresh frozen-section specimens helps to:

• Provide a rapid microscopic analysis of the specimen
• Establish whether the entire area of disease has been successfully removed during surgery (examining the margins of the frozen section)
• Guide the progression of the surgical procedure

Our surgical pathology division reflects the various subspecialties of our highly qualified, board-certified pathologists. Subspecialization allows for increased experience and skill for the interpretation of challenging cases. Areas of extensive experience and subspecialization include:

• Breast pathology
• Cardiac pathology
• Gastrointestinal/hepatic pathology
• Genitourinary/renal pathology
• Gynecologic/reproductive pathology
• Perinatal pathology
• Thoracic/soft tissue/endocrine pathology

Many pathologists are also actively engaged in translational or laboratory research within their specialty.

Our breast pathology specialists provide comprehensive diagnostic expertise relating to the pathologic evaluation of benign and malignant disorders of the breast. These specialists evaluate all breast needle core biopsy specimens generated by breast imaging, all large surgical breast specimens (such as excisions, re-excisions and mastectomies) generated by breast surgery and offer second opinion breast consultation services. They also perform state-of-the-art analysis of predictive and prognostic breast tumor markers using a variety of immunohistochemical and molecular techniques.

The breast pathology section is a key component of the Lynn Sage Breast Cancer Center of Northwestern University that emphasizes an effective multidisciplinary approach to the care of patients with breast disease.

The Neuropathology division is responsible for interpreting the pathology in surgical specimens from the brain and spinal cord, including biopsies and resections. Clinicians use this information to plan treatment of patients with tumors, inflammatory and demyelinating conditions and other disease processes.

This division is also responsible for interpreting the pathology in brains and spinal cords during autopsy. Autopsy findings assist clinicians in understanding the disease process and the results of various diagnostic investigative procedures to optimize future processes.

The Perinatal Pathology division is responsible for examining placentas and fetal specimens in surgical pathology. Prentice Women’s Hospital has one of the largest obstetrics services in the country, with more than 13,000 deliveries annually. Therefore, this specialized perinatal pathology service is important to obstetricians and neonatologists who care for the mothers and babies.

Additionally, this division is responsible for performing autopsies in cases of perinatal and/or neonatal death. A majority of these autopsies are performed on stillborn fetuses and establishing a probable cause of death in these cases is very important for clinicians and families.

Cardiac pathology is the subspecialty of surgical pathology that focuses on diagnosing and characterizing pathology specimens related to cardiovascular conditions and diseases.

Gastrointestinal/hepatic pathology is the subspecialty of surgical pathology that focuses on diagnosing and characterizing diseases of the gastrointestinal tract and the accessory organs, such as the pancreas, biliary tract and liver.

Genitourinary/renal pathology is the subspecialty of surgical pathology that focuses on diagnosing and characterizing diseases of the urinary tract and the male genital tract. Renal pathology focuses on disorders of the kidney.

Gynecologic/reproductive pathology is the subspecialty of surgical pathology that focuses on the study and diagnosis of diseases of the female reproductive tract.

Thoracic pathology is the subspecialty of surgical pathology that focuses on diagnosing diseases of the lung, pleura and mediastinum. Soft tissue pathology deals with characterizing neoplastic and non-neoplastic disease of the soft tissues, including the muscles, tendons, fascia, connective tissues and adipose tissue. Endocrine pathology primarily works with the organs of the endocrine system, including the thyroid, parathyroid glands and adrenal glands.

The Blood Bank division of the clinical laboratory performs blood typing and cross-matching and provides blood components for patients who need transfusions. The Blood Bank provides red blood cells, platelets and plasma to treat anemia, bleeding disorders and hemorrhage in trauma and surgery. Additionally, the Blood Bank provides special diagnostic testing for patients with auto-antibodies against their own red blood cells and for pregnant women at risk of making antibodies which could attack their babies' red blood cells.

The Chemistry division is responsible for measuring the levels of various molecules relevant to disease in blood or other bodily fluids. Data generated in the chemistry laboratory are used to monitor a patient’s:

• Health status
• Disease progression
• Drug levels
• Response to treatment

The Cytogenetics Division performs conventional cytogenetic and fluorescence in situ hybridization (FISH) analysis to detect chromosome and gene abnormalities in forms of cancer. These genetic assessments are critical in establishing a diagnosis that helps clinicians determine optimal treatment protocols, in monitoring treatment response and disease status and in determining disease risk stratification and prognosis.

The clinical Flow Cytometry laboratory offers crucial diagnostic data used in management of leukemia, lymphomas and other diseases. The lab measures multiple molecules on or in individual cells that are related to the lineage and differentiation of cells in the blood, bone marrow and lymphoid organs. These measurements are also used by clinicians to monitor a patient’s immune status in the wake of certain treatments.

The Hematology and Hematopathology division measures and evaluates the cells in the blood and also in other bodily fluids, such as cerebrospinal fluid. The data generated in the Hematology lab is used to monitor patient health and to evaluate patients with disease, particularly those with disorders that may affect the blood.

The Hematopathology section provides comprehensive diagnostic expertise in evaluating benign and malignant disorders of the blood, bone marrow, lymph nodes and other tissues. This section is a member of the multidisciplinary team that provides care for patients with hematologic diseases that are seen at Northwestern Memorial Hospital.

The Hemostasis/Coagulation division is responsible for measuring the hemostatic properties of blood and platelets in blood relevant to health and disease. This division performs high-volume screening as well as specialized lab testing. Clinicians use data generated here to screen for disorders of hemostasis and thrombosis, and to monitor responses to various replacement, antiplatelet and/or anticoagulation therapies.

The Immunology division is responsible for measuring the levels, in blood and other bodily fluids, of various auto-antibodies (antinuclear antibodies) and other antibodies, paraproteins and anomalous synthesis of immunoglobulins.

The clinical Microbiology laboratory offers state-of-the-art infectious disease laboratory diagnosis and consultation services for clinical staff and physicians.

Our laboratory expertise includes:

• Bacteria identification and susceptibility testing
• Mycology
• Mycobacteriology
• Parasitology
• Molecular microbiology
• Molecular epidemiology

The Molecular Diagnostics division is responsible for nucleic acid—DNA- and RNA-based—diagnosis in four areas:

• Genetics
• Infectious diseases
• Hematopathology
• Solid tumors

Team members collaborate with other sub-specialist pathologists to provide integrated, multimodal analyses of genes and tissues in virtually all areas of human health and disease.

The Virology division provides a full range of diagnostic services for the detection and monitoring of viral infections and for the determination of immune response to viral antigen exposure. The data gathered in Virology is used by clinicians to make the diagnosis of viral infection, assess the response to antiviral therapy and to determine a patient's immune status to viral pathogens.