The pathologist and the clinical oncologist: a new effective partnership in assessing tumor prognosis.

During the past 20 years, we have witnessed a progressive radical change in the role of the pathologist vis à vis several aspects of clinical oncology. From the traditional description by light microscopy of resected specimens and study of tumor classifications, the modern pathologist has expanded his domain of action which now results in deeper and more effective interactions with the surgeon, radiotherapist and medical oncologist. The wide application of fine-needle biopsy has substantially improved early diagnosis of primary neoplasms and local and distant recurrences. The histogenetic classification based on type of tissue formed by the tumor rather than type of tissue from which tumor arises, the results of pathologic staging as well as the degree of tumor cell necrosis following primary chemotherapy are now being correlated with treatment outcome. The assessment of tumor grade and ploidy can allow more accurate selection of patient subgroups at high risk of early relapse. Last but not least, the morphologic recognition of certain types of iatrogenic morbidity helps in the reassessment of given drug combinations. During the past decade, pathologists have contributed to the development of several new investigative techniques whose first applications, in most instances, were in laboratories dedicated to basic research. More recently, some pathologists have begun to explore the feasibility of applying these same techniques to clinical cancer research. Modern sophisticated technology, including flow cytometry, immunohistochemistry and monoclonal antibodies, can now provide research physicians with important prognostic indicators such as tumor cell proliferative activity, steroid receptor status, occult distant micrometastases, immunologic phenotypes and gene amplification. By fulfilling several new tasks, which have contributed to the knowledge of the natural history of many tumors, the pathologist has become an integral part of the team planning new treatment strategies and evaluating their final outcome.