Reproducibility of microvessel counts in breast cancer specimens

Abstract

Assessment of tumour vascularity in core biopsy specimens may be a useful predictor of response to primary therapy. This study addresses practical methodological issues regarding accuracy of tumour vascularity assessments in different breast cancer specimens. Issues addressed in the study are variation caused by (i) inherent observer variation in the method, (ii) tumour heterogeneity and (iii) previous surgical manipulation of tumours. Microvessel counts were performed by two observers on separate occasions and by two different observers. Counts were performed on core biopsies and tumour sections taken simultaneously ( n = 16) and with an intervening time interval ( n = 21). In addition core biopsies were obtained from the same tumour on two separate occasions ( n = 10). A highly significant correlation was found in counts performed by the same observers at different times and between two different observers. No significant correlation was found in counts of core biopsies and tumour sections taken either simultaneously or subsequently. No correlation was found between counts of sequential core biopsies. Study findings suggest that, although microvessel counts may be assessed reproducibly by the same and different observers, counts performed in core biopsies do not accurately reflect those of overall tumour, limiting their potential as predictive or prognostic markers. © 1999 Cancer Research Campaign

Three‐dimensional power Doppler imaging of early‐stage cervical cancer

“…It is arguable that the number of vessels counted in areas of high vascularity does not provide a global assessment of the tumor. The inability to accurately reproduce microvessel counts has been found in both breast29 and cervical cancers30. This is due in part to the experience of investigators, tumor vascular heterogeneity, and the selection of representative tumor blocks.…”

Angiogenesis induction and regression in human surgical wounds

“…Although much of the information is contradictory, there is consensus from a number of studies that CD31 is the most sensitive marker of vessel endothelium. 30,31 This antibody was used in combination with the Chalkley grid and is considered superior to similar methods that involve counting all vessels in the whole field of view, 32 as it is less subjective. 33 The main criticism of the Chalkley grid method is the subjectivity of choosing hot spots and variable reproducibility.…”

Effects of Raloxifene on Ki-67 and CD34 Antigen Expression in Breast Cancer

“…The results of the present study are unlikely to simply reflect tumor heterogeneity, which is a recognized problem of methodology. Studies investigating the effect of tumor heterogeneity on MVD in breast cancer specimens have focused on the use of core biopsies [24,25] , which contain a smaller tumor volume than the preoperative wedge biopsy carried out in the present study both prior to and following treatment. Nevertheless, events other than raloxifene may affect changes in proliferation and vascularity, since angiogenesis is a complex and dynamic process that is stimulated in situations other than tumor growth such as tissue hipoxia and previous surgical manipulation of the tumor as part of the process of wound healing, although the duration of such effects is not known [9] .…”

“…The 4-hydroxytamoxifen metabolite inactivates the ER transcriptional activation function 2 (TAF-2) gene which is predominant in the breast and activates TAF-1 predominantly in the endometrial cells. In contrast, raloxifene inactivates both TAF-1 and TAF-2, resulting in an antiestrogenic effect both on the breast and on the endometrium [6,25] .…”