This edition of Pathology Case Reviews deals with a range of pulmonary pathology diseases and conditions that reveal the broad spectrum of issues relating to lung anatomy and histology, inflammatory and neoplastic diseases, and innovations in molecular medicine and medical decision analysis. The lung is exposed to the outside environment, perfused by the entire cardiac output, and is sensitive to many systemic diseases, and consequently, pulmonary pathology represents a broad range of particular and systemic disease and syndromes. The pathologist understands that decision making in pulmonary pathology does not begin at the microscope, but rather, analogous to other critical organs and systemic conditions, the history, physical examination, including pulmonary function tests, and the radiographic images represent an important database to begin examination of available pulmonary gross review and histopathological analysis. The integration of the patient history, pulmonary function tests, radiographic images, and pathology should tell a unique coherent story to ensure a correct diagnosis. Diagnostic pulmonary pathology therefore represents a collaborative team approach where clinical colleagues and radiologists participate actively in the review of routine and challenging cases. Clinical information systems and electronic medical records may display clinical information, laboratory results, and radiographic images on anatomic pathology systems. Although many pathologists have these clinical information systems available to them, enhancing their appreciation of the total clinical picture, we recommend that diagnostic pathologists participate in clinical conferences and open direct discussions with their clinical peers to gain additional insight into their cases and appreciate the consequence of their pathological analysis and diagnostic decisions.
Fundamental to a working knowledge of pulmonary pathology are the concepts and insights of the pathological process underlying the disease condition. The pathology may be inflammatory/infectious or inflammatory/noninfectious, reactive or neoplastic, or primary or iatrogenic. The complete clinical database and the histopathological review should inform the pathologist with the temporal nature of the process, opportunities for intervention and reversal of the natural history of disease, insights into the etiology and mechanism of injury and host response, and prognostication of clinical behavior and outcome. In addition to discovering the presenting clinical database, pathologists should also seek out the clinical follow-up of their cases.
In this issue, we present 7 case studies, by recognized experts in the field of pulmonary pathology, which typify many of the considerations addressed in this Editorial. Dr Litzky’s group presents a case of diffuse interstitial lung disease with a near 2-decade follow-up. The case shows the importance of association of clinical, radiological information over time along with pathological review. It also shows an important mechanistic connection between chronic inflammatory processes and neoplasia. Dr Jones discusses 2 interesting cases of pulmonary crystal storing histiocytosis that include airspace, nodular, and interstitial disease in the differential diagnosis. Laboratory and radiographic imaging is critical for diagnosis and prognosis. Dr Roggli’s group introduces a case of sclerosing hemangioma of the lung, a pulmonary neoplasm in need of nomenclature review. The variable histological patterns challenge the diagnostic pathologist and awareness of radiographic features, histological types, immunohistochemical phenotyping, and ultrastructural analysis will aid in the differential diagnosis. Drs Ohori and Karunamurthy present an unusual case of a typical carcinoid tumor with neurogenic differentiation, similar to cases of abdominal neuroendocrine tumors having gangliocytic maturation. Drs Durra and Flieder demonstrate in their case study that squamous cell carcinomas may present as peripheral-based cancers, a feature usually appropriated by adenocarcinomas. Their work is well documented and reinforces the need for ancillary studies. Dr Nolan shares a case report of an adenocarcinoma with EML-4/ALK translocation and reviews the topic of this oncogene-driven malignancy and the opportunity for molecular pathway target–driven therapy. Finally, my colleague, Dr Rezaei and I review the topic of intraoperative consultations in lung pathology with an emphasis on decision analysis techniques.
We hope that you find the cases interesting, informative, and helpful in improving your clinical practice of pulmonary surgical pathology.