Extra-tumoral breast tissue in breast-cancer patients: variations with a family history of breast cancer. WHO Collaborative Study of Neoplasia and Steroid Contraceptives.

In order to study the relationship between benign breast changes, a family history of breast cancer and breast cancer, extratumoral breast tissue from 1259 breast-cancer patients in the WHO Collaborative Study of Neoplasia and Contraceptives was classified histologically. The occurrence of ductal hyperplasia, ductal atypia, sclerosing adenosis, adenosis, lobular atypia, lactational metaplasia, cysts, apocrine metaplasia, apocrine hyperplasia and atypia, duct ectasia and the epithelial-stromal ratio was evaluated as absent, mild, moderate or marked, along with registration of the quality and number of slides. Information on occurrence of cancer in the family was available for patients' mothers and grandmothers. Logistic-regression analyses showed that the prevalence odds ratios for lactational metaplasia, cysts, duct ectasia and calcification were significantly increased in patients with a family history of breast cancer. Apocrine metaplasia and hyperplasia were not significantly increased. The prevalence rates of ductal atypia (ductal carcinoma in situ and atypical ductal hyperplasia), ductal hyperplasia, sclerosing adenosis, adenosis and high epithelial-stromal ratio did not differ significantly among patients with or without a family history of breast cancer. A family history of other types of cancer did not influence the occurrence of any of the benign components. The findings in the present study are strikingly similar to those in our earlier comparison of extra-tumoral breast tissue in patients from countries with high and low risk of breast cancer. It is reasonable to conclude from this that a history of breast cancer in a woman's mother or grandmother and the factors leading to higher risk of breast cancer in some countries than in others have similar effects on the morphologic evolution of breast cancer through benign and pre-cancerous changes.

Extratumoral breast tissue in breast cancer patients: a multinational study of variations with age and country of residence in low- and high-risk countries. WHO Collaborative Study of Neoplasia and Steroid Contraceptives.

With the aim of elucidating the relationships between breast cancer, risk factors and benign breast changes, extratumoral breast tissue in 1,506 women from the WHO Collaborative study of neoplasia and steroid contraceptives was studied histologically. Patients came from 3 countries with a high incidence of breast cancer (Israel, East Germany and Australia) and 6 low-risk countries (Thailand, China, Philippines, Mexico, Chile and Colombia). Ductal atypia, ductal hyperplasia, adenosis, lobular atypia, apocrine metaplasia, apocrine hyperplasia, apocrine atypia, cysts, duct ectasia, inflammatory reaction, calcification, lactational change and epithelial-stromal ratio were classified as absent/mild/moderate/marked. Prevalence odds ratios were calculated by logistic regression analyses. Increasing frequency with age was found for ductal hyperplasia, sclerosing adenosis, apocrine metaplasia and cysts, while adenosis, lactational change and the epithelial-stromal ratio decreased with age. No significant difference between high- and low-risk countries was found for ductal hyperplasia or sclerosing adenosis. Compared with cases from high-risk countries, those from low-risk countries had a significantly lower prevalence of apocrine metaplasia, apocrine hyperplasia and cysts, and a significantly higher prevalence of ductal atypia. When seen in conjunction with other studies, the results suggest that ductal hyperplasia and sclerosing adenosis have similar roles in cancer development in high- and low-risk countries and that the factors responsible for international differences in breast cancer may exert their effect by influencing the initial development of these changes. They also suggest a delayed progression from noninvasive to invasive carcinoma in low-risk countries.