Her2/neu/cerbB2 GENE AMPLIFICATION IN UROTHELIAL CARCINOMA VARIANTS AND NON UROTHELIAL CARCINOMAS OF THE BLADDER

ABSRACT

Bladder cancer is the seventh most common cancer worldwide, with an estimated 260, 000 new cases occurring each year in men and 76,000 in women. According to the World Health Organisation (WHO),  there are eleven different variants of infiltrating Urothelial Carcinoma, these include; UC with squamous differentiation, UC glandular differentiation, UC with trophoblastic differentiation, nested UC, microcystic UC, micropapillary UC, and the lymphoepithelioma-like variant.mNon-urothelial carcinomas include small cell carcinomas, adenocarcinomas and squamous cell carcinoma

The aim of this study is to establish whether amplification of the Her2 gene is present in certain rare types of bladder cancers;the variants of urothelial carcinoma and the non-urothelial carcinomas of the bladder.

Both Immunohsitochemical and Fluorescence in situ hybridization methods we used for this study. A mean Her2 copy number was calculated for each case, based on the counting of signals in 40 tumour cells per case.  The mean Her2 copy number calculated for all 25 cases scored was 2.99, with a range from 1.47 to 4.45. Twelve of 25 (48%) cases showed 2+ staining and 5 (20%) showed 1+ staining.  A total of 7 (32%) were completely negative, showing no cell membrane staining, and in 1 case (4%; Case 25) the results were undeterminable due to the presence of nuclear staining in tumour cells.  This study showed poor correlation between immunohistochemical expression of the Her2 protein and FISH analysis of the Her2 gene in some types of bladder cancer

Bladder cancer is the seventh most common cancer worldwide, with an estimated 260, 000 new cases occurring each year in men and 76,000 in women. It is the 4th most common cancer for men and 10th common cancer among women.  Bladder cancer is an aggressive disease with an increasing incidence.  There are many different factors which can contribute to bladder cancer the most important among them is cigarette smoking.  Other potential risk factors include occupational exposure to aniline dyes (usually male patients), chronic infections such as that caused by Schistosoma haematobium, Arsenic, and medicinal drugs such as the chemotherapeutic agent cyclophosphamide.