OBJECTIVE: The aim of this study was to determine the reproducibility of the HERCEP-test (Dako Co. Carpintería Ca) for the assessment of HER-2/neu protein overexpression in archival tissues samples of women with ductal invasive breast carcinoma. MATERIALS AND METHODS: The study population was 40 retrospective and consecutive cases of women with ductal invasive breast carcinoma. The tumors were graded by the Elston and Ellis modified Scarf, Bloom and Richardson score. For immunohistochemical studies, 4 microns thick sections were cut and were immunostained with the HERCEP-test kit. We evaluated the overexpression using the numeric score approved for the FDA of USA, ranging from 0 to 3+ reflecting the intensity and pattern of the immunohistochemical signal present in 10% or more of tumor cells. The slides were reviewed twice independently and blinded by two pathologists. The second assessment was made two months after the first one. The level of inter and intraobserver was quantitated using kappa statistics. RESULTS: The interobserver agreement was 0.98 and the intraobserver agreement was 1.00 and 0.87 respectively. There was no significant differences in the assessment of the different scores of the numeric scale. CONCLUSION: The reproducibility of the numeric score evaluated was excellent.
OBJECTIVE: The aim of this study was to determine the reproducibility of the HERCEP-test (Dako Co. Carpintería Ca) for the assessment of HER-2/neu protein overexpression in archival tissues samples of women with ductal invasive breast carcinoma. MATERIALS AND METHODS: The study population was 40 retrospective and consecutive cases of women with ductal invasive breast carcinoma. The tumors were graded by the Elston and Ellis modified Scarf, Bloom and Richardson score. For immunohistochemical studies, 4 microns thick sections were cut and were immunostained with the HERCEP-test kit. We evaluated the overexpression using the numeric score approved for the FDA of USA, ranging from 0 to 3+ reflecting the intensity and pattern of the immunohistochemical signal present in 10% or more of tumor cells. The slides were reviewed twice independently and blinded by two pathologists. The second assessment was made two months after the first one. The level of inter and intraobserver was quantitated using kappa statistics. RESULTS: The interobserver agreement was 0.98 and the intraobserver agreement was 1.00 and 0.87 respectively. There was no significant differences in the assessment of the different scores of the numeric scale. CONCLUSION: The reproducibility of the numeric score evaluated was excellent.