Tissue Microarray Analysis of HER2 copy number changes in Ovarian cancer

Abstract

This study was accomplished inMedicalUniversity– Pathologoanatomic  Department of the Clinic of Thoracic Surgery.Sofia,. Bulgarian, were collected the paraffin blocks, by using new technology Tissue microarrays (TMA) and Fluorescence In Situ Hybridization (FISH)) on different   type of ovarian tumors .  The method of FISH applied on TMA with HER1 and HER2 specific probes proved itself as the most commonly used and valuable analysis for routine HER2 status detection and copy number changes . The results showed in out of all 603  ovarian carcinomas examined, the number of successfully hybridized for HER2  oncogene is 303 (50.2%) 192  of them are malignancies tumors(179 epithelial and 13 non epithelial ) ,18 low malignant ovarian tumors( just epithelial ), 93 – Benign ovarian tumors(77 epithelial and 16 non epithelial ) . We established HER2 amplification in malignancies tumors only 20  (10.41%) ,19 (10.61%) epithelial and  in 1 (7.69%) non epithelial ) .  There is no amplification in tumors with low malignant potential and Benign ovarian tumors. While we found HER2 gains  in malignancies tumors , low malignant ovarian tumors and Benign ovarian tumors only 19  , malignancies 14 about (7.29%) ,low malignant 2 (11.11%) and in Benign ovarian tumors 3 (3.22% ).

Epithelial malignant tumors among the highest incidence of HER2 amplification was detected in Clear cell carcinomas 2 (28.57%) and rank them Endometrioid 2 (16.66%), Serous 9 (10.46%), undifferentiated tumors 2 (11.11%) and mixed(combined) 2 (11.76%), Mucinous 1 (6.25%) and Unclassification 1 (4.55%). HER2 amplification was found in 1 of 13 non epithelial malignant tumors, Sex-cord stromal tumours 1 (7.69%). HER2 gains  in malignancies tumors was detected in serous 5 (5.81%) ,endometrioid 1 (8.33%) , undifferentiated 2 (11.11%) , mixed (combined) 2 ( 11.7%) and mucinous1 (6.25%), in low malignant ovarian tumors was detected HER2 gain only  in mucinous 2 (11.11%) and Benign ovarian tumors only in serous 3 (7.69% ).Were preserved at the grouping of tumor samples according to the WHO classification.