Immunohistologic characterisation of benign lymphoepithelial-like breast lesions

Ten cases with benign breast lesion consisting of dense intralobular, perilobular, and perivascular lymphocytic infiltrates associated with lobular atrophy and sclerosis had been studied with 20 cases of breast cancers of similar average size and age group for characterisation of the predominant lymphocytic population using monoclonal antibodies. Documented immunologic disorders were present in 5 out of 10 cases [rheumatoid arthritis, diabetes mellitus, and thyrotoxicosis], B cell predominance was found in 8 cases while almost equal proportions of both T and B cells was found in 2 cases. Breast carcinoma cases with lymphocytic infiltrate showed predominance of T cell population which was also found around adjacent non neoplastic lobules and ducts. So it is postulated that characterisation of lymphocytic population in such benign lymphoepithelial lesions might be of help in differentiating them from the predominantly T cell infiltrate around benign lobule or duct associated with deeply seated breast malignancy

Laminin and fibronectin expression in breast carcinomas

Fourty nine cases of breast cancer were stained for laminin and fibronectin. These cases include 41 cases of invasive duct carcinoma [IDC], 6 cases of invasive lobular carcinoma [ILC], one intraduct carcinoma and one tubular carcinoma. Laminin loss was more frequently associated with poor tumour differentiation, being lost in 70.6% and 72 .7% of tumours of histologic grade II and III respectively as compared to 61.5% of tumors of grade I. Also laminin loss was associated with increased incidence of lymph node metastases. Lymph node metastases were present in 60% of laminin negative tumours compared to 38.5% of tumours with preserved although abnormal laminin. These findings point to a probable good prognostic value for laminin preservation in invasive breast cancer. However the presence of laminin in some cases of grade III with >/= 4 lymph node metastases open discussion about a possible role for laminin in promoting invasion and metastases in some cases of breast cancer. A scanty or absent fibronectin was found in the majority of ILC [5/6] in contrast to prominent diffuse stromal staining for fibronectin in 27 out of 41 cases of IDC. This difference in fibronectin staining may be related to the characteristic infiltrating pattern and different behaviour of lLC

Vimentin expression in malignant versus benign breast lesions

Benign breast lesions [16 cases] and breast carcinoma [39 cases] were stained for vimentin and cytokeration in consecutive sections. Occasional vimentin staining in less than 5% of breast epithelium was considered as a variant of normal. Vimentin positivity in 5% of epithelial cells was present in one case of fibrocystic disease with moderate epitheliosis as compared to 7 cases of IDC. ILC and intraduct carcinomas were vimentin negative. Vimentin positivity was found preferentially in histologic grade III [36.4%] as compared with grade II [13.3%] and grade I [10%]. Also vimentin positive tumours were associated with increased lymph node metastases [71.4% in vimentin positive tumours versus 51.6% in vimentin negative tumours]. Although the number of vimentin positive cases was small, the extent and intensity of staining were impressive and may be of biological impact on tumour behaviour as suggested from the preferential expression of vimentin in tumours with high histologic grade and more incidence of lymph node metastases. Also the knowledge of the group of epithelial tumours expressing vimentin, with breast cancer as a recent member in this group, is of considerable importance when using vimentin as a marker of cells of mesodermal origin only

Study on high endothelial venules [HEVs] in reactive lymph nodes versus non-Hodgkin's lymphomas

The number of post-capillary venules with high endothelial cells [HEVs] was studied in 10 cases of reactive lymph nodes and 20 cases of non.Hodgkin lymphomas [NHL]. Reactive lymph nodes showed higher numbers of HEVs [mean 7.14, SD 0.56] while it was much lower in NHL [mean 3.62, SD 1.57]. The number of HEVs was higher in low grade NHL than those of intermediate grade malignany. It was the least in diffuse large cell lymphoma [mean 1.3, SD 0.32]. A statistically significant difference [P< 0.001] was found between reactive hyperplasia and NHL cases. Also a significant difference [P<0.001] was found between follicular lymphoma [10 cases, mean 4.83. SD 0.61] and diffuse lymphoma [5 cases, mean 1.44. SD 0.41]. So the presence of HEVs with normal structure and with signs of active migration of lymphoid cells may facilitate the dissemination of lymphoma cells