Breast cancer in Western Australia in 1989: IV. Summary of histopathological assessment in 655 cases.

This study was part of a population-based survey of all cases of breast cancer diagnosed in Western Australia in 1989. The paper concerns histopathology reporting by pathologists in 655 cases of carcinoma of the breast in that year, before the introduction of mammographic screening programmes. Pathological features of the neoplasms are documented, and the extent to which information known to be of clinical or prognostic importance was included in the reports is analysed. 96.5% of all pathology reports included information on breast cancer subtype and, in 98.6% of cases with axillary dissection, the number of lymph nodes dissected, and the number containing metastatic tumor was stated. In 83.7% of cases of invasive carcinoma exact tumor dimensions were recorded. In 44.9% of cases histological grade was recorded, and information about excision margins was present in 60% of reports overall. The reporting of pathological features in many instances was limited by the way in which the specimen was handled prior to reception. At the time of the study, views about the importance of many aspects of histological assessment were still evolving. Even now, for example, consensus is still being reached on the value of histological grading in predicting prognosis and whether reliable histological assessment of such factors as extent of DCIS and completeness of excision of DCIS is possible. The introduction of mammographic screening since 1989 has provided a focus for wider discussion about the value of histological information in prognostication and patient management. A case is made to support the use of "check lists" for surgical pathology reports in cases of breast cancer.