Rosen's Breast Pathology, 4e

I NTRODUC T I ON

The Pathologist as a Specialist in Breast Carcinoma Care The development and application of a concept of localized pathology laid the groundwork for modern specialism by providing a number of foci of interest in the field of medicine. Each such focus of interest, that is, a disease or the diseases of an organ or region of the body, provided a nucleus around which could gather the results of clinical and pathological investigation . —From The Specialization of Medicine by George Rosen, MD , 1944. Impressive advances have been made in the past 60 years to detect, treat, and cure breast carcinoma. Major milestones include the development of mammography for early detec- tion, the refinement of image-based needle biopsy of non- palpable lesions, the introduction of computed tomography (CT) and magnetic resonance imaging (MRI) of the breast, the shift from mastectomy to breast conservation therapy for almost all patients, technologic advances in radiotherapy, improved chemotherapy regimens for primary treatment and as an adjuvant modality, the demonstration that anti- estrogenic compounds can inhibit the development and progression of breast carcinoma, the introduction of sentinel lymph node mapping for axillary staging, and technologic advances that make gene expression profiling possible. The growth of medical specialization in the last half of the 20th century has had a profound influence on these accomplish- ments by fostering multidisciplinary clinical practice and research. Specialism in all aspects of medical care has revolution- ized the role of the surgical pathologist. Rather than foster- ing professional independence, specialization in medicine has created circumstances in which the specialist, delivering a limited segment of medical care, is increasingly dependent on the assistance of colleagues who have acquired comple- mentary expertise. This situation is epitomized by the mul- tidisciplinary approach that is now standard for treating breast diseases. Inherent in this circumstance is the expecta- tion that each member of the team is capable of delivering optimal specialty care. A corollary effect is the growing pres- sure for subspecialization in diagnostic pathology in aca- demic centers and in large community hospital centers. This process will be furthered by growing awareness on the part of patients and patient advocacy organizations that accurate and comprehensive pathology diagnosis is fundamental to effective treatment and research in breast diseases. Even when considered in the context of advances in diagnosis that have been facilitated in recent decades by immunohistochemistry and molecular analysis, micro- scopic examination of hematoxylin and eosin–stained tis- sue sections combined with gross inspection remains the most cost-effective diagnostic procedure for breast diseases.

Pathologists generate an important part of the information used for therapeutic decisions. The complex multifacto- rial description of breast pathology now considered to be standard practice has expanded the diagnostic report from a brief one- or two-line statement to a catalog of data that may be several pages in length. Immunohistochemistry makes it possible to determine whether prognostic and therapeutic markers are present by microscopic examination, and these observations are part of the pathologist’s report. The ex- panded role of pathologists in the management of breast dis- eases requires their active participation as part of the clinical care team. Pathologists who diagnose breast specimens need to be aware of how various components of their reports are relevant to treatment decisions. Coincidental with these medical developments has been the growing involvement of patients in making decisions about their treatment. This, in turn, has led to greater pub- lic awareness of the importance of information contained in pathology reports. For the untrained layperson to read and interpret a pathology report, it is necessary to learn and understand a new vocabulary, a daunting task that is not necessarily made easier by the frequently conflicting and unfiltered information available from the Internet. Surgeons, oncologists, and radiotherapists are experts at interpreting pathology reports for their patients and at explaining the significance of the data. Nonetheless, a sub- stantial number of patients with breast diseases want an explanation from the pathologist who issued the report or they seek out another pathologist, often with specialized expertise, for a second-opinion review. In this way, patholo- gists increasingly participate in direct patient care and pa- tient education, a vital public service. Second Opinions in Breast Pathology Surgical pathologists in general practice provide accurate diagnoses for the great majority of the breast specimens they encounter without the assistance of intramural or extramu- ral consultation. Nonetheless, pathology departments that do not have a dedicated breast pathology subsection should have a built-in mechanism for obtaining second opinions internally through conferencing or other quality assurance programs. As evidenced by a number of papers published in recent years, there is growing recognition of the importance of having an intradepartmental peer-review quality assur- ance program in order to minimize diagnostic errors. 1–3 Procedures have been described for internal review shortly after the diagnosis was officially reported 4 and for pre-sign- out review. 5 For detailed discussions of quality assurance issues in surgical pathology, the reader should consult the aforementioned articles and references cited therein.

xiii