FREQUENCY OF DISTRIBUTION OF OESTROGEN AND PROGESTERONE RECEPTOR POSITIVITY IN BREAST CANCER IN UNIVERSITY OF BENIN TEACHING HOSPITAL (U.B.T.H), BENIN-CITY, NIGERIA

Abstract

Introduction/Aim: The expression of steroid hormone receptors in breast carcinoma is
emerging as an important prognostic factor as well as a predictor of likely response to
hormonal modulatory therapy. For example, patients with ER-positive tumours derive
significant benefit from 5 years use of tamoxifen in reducing the odds of recurrence and
death, whereas women with ER-negative tumours do not. However in Nigeria as in most
other developing countries, there is a dearth of information, principally because of the lack of
immunohistochemical test facilities, on the pattern and prevalence of steroid hormone
receptor expression in breast cancer and patients are therefore blindly placed on tamoxifen
therapy. The aim of this study is to determine the prevalence of oestrogen receptor and
progesterone receptor positivity among histologically diagnosed breast cancers at the
University of Benin Teaching Hospital, Benin City, Nigeria.
Materials and Method: Cases of breast carcinomas received in the department of
Histopathology, University of Benin Teaching Hospital, between 2003-2007 were used for
this study. Relevant information was obtained from the records in the Surgical day books of
the department. Sections of representative paraffin-embedded blocks (by H&E slides
assessment) were recut for histological grading and immunohistochemistry. The
immunohistochemical technique employed was the immunoperoxidase method. The panel of
antibodies was for oestrogen and progesterone receptors.
Results: A total of 135 cases were studied. The female to male ratio was 44:1 with an overall
mean age of 48.3 years. Invasive ductal carcinoma, NOS was the most common histological
type (81.5%). Eighty percent of cases were categorized as grades 2 and 3 tumours. The
steroid hormone receptor positivity was 17%. Oestrogen and Progesterone receptor positivity
were 14.1% and 9.6% respectively. There was a statistically significant association between
hormone receptor status and the grade of tumour ( χ2 = 6.37, df = 2, p = 0.04).

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Conclusion: This study shows a relatively low steroid hormone receptor positivity of breast
cancer in this group of patients, a finding that would portend a poor prognostic effect.
Furthermore, it would appear that the current habit of a non-discriminatory hormonal
treatment for all patients with breast cancer is superfluous and will not yield maximum
benefit in our environment. We would suggest therefore that steroid hormone receptor status
be determined before treatment in each case. There is the need to determine the
immunohistochemical patterns of breast cancer in other centres that treat breast cancer
patients. From the wider cohorts studies it will be possible to confirm or refute our finding of
low steroid hormone receptor expression pattern in Nigerian breast cancer cases.