pTNM Stage Distribution in Breast Cancer: A Population-Based Survey in Northern Italy

Abstract

Aims and background The role of distribution by stage at diagnosis in breast cancer has been considered in many studies, with particular regard to evaluation of prognosis, impact of screening programs and quality of care. Nevertheless, international comparisons of descriptive data can be hampered by lack of homogeneity in staging methods. The TNM is presently the most common staging system used all over the world, although some criticism have been raised recently against its pragmatic value. The present study reports a population-based survey of pathologic TNM distribution in incident cases of female breast cancer in the Verona province, a geographical area of northern Italy covered by cancer registration. Methods All histologically proven incident cases of breast cancer were identified in the study period 1988-1990 and classified as for tumor size and nodal involvement according to the pathological TNM criteria. The type of surgical treatment was also registered for all cases diagnosed in 1990. Results one thousand two hundreds and fifty-four invasive and in situ breast cancers were observed and pT1 cases accounted for 44.4%. Nodal involvement was present in 41.5% of invasive cancers. A surgical treatment was performed in 1213 patients (96.7%). Axillary dissection was reported in 1080 cases, 820 of them (76.6%) having 10 or more lymph nodes examined. Radical mastectomy accounted for 74% of the 458 breast cancers diagnosed in 1990 and 31.6% of the eligible cases were conservatively treated. Conclusions Cancer registries should be encouraged to report data on stage distribution in breast cancer (and in other malignancies). This practice could improve international comparisons and give an essential contribution to studies on survival, screening programs and quality of care.