Estrogen and progesterone receptors in the endometrium of postmenopausal breast cancer patients treated with tamoxifen and progestogens

Are endometrial polyps from pre-menopausal women similar to post-menopausal women? An immunohistochemical comparison of endometrial polyps from pre- and post-menopausal women

OBJECTIVE

Do endometrial polyps from pre- and post-menopausal women have similar immunohistochemical expression of oestrogen and progesterone receptors (ER, PR) and markers of cellular proliferation/apoptosis (Ki67 and Bcl-2).

DESIGN

Prospective cohort study. Non-parametric statistical analysis was used.

SETTING

Polyps recruited from women attending an out-patient hysteroscopy clinic in a UK district general hospital.

PATIENTS

Fourteen pre-menopausal and 16 post-menopausal women who presented with abnormal bleeding with endometrial polyps.

INTERVENTIONS

Immunohistochemical staining was performed on endometrial polyps.

MAIN OUTCOME MEASURES

Significant differences or correlations between hormone receptor expression (oestrogen and progesterone) and cell growth indices (Ki67 and Bcl-2).

RESULTS

Endometrial polyps from pre- and post-menopausal women had significant differences in their expression of hormone receptors and Ki67. However, polyps from both groups of women had similarly increased levels of Bcl-2, an inhibitor of apoptosis.

CONCLUSIONS

Pre- and post-menopausal polyps exhibit differing hormone receptor and proliferation markers, presumably a result of their hormonal milieu. However, both groups appear to have lost the usual control mechanisms for apoptotic regulation, this appears to be responsible for their growth.

An immunohistochemical comparison of endometrial polyps from postmenopausal women exposed and not exposed to HRT

OBJECTIVE

Our study set out to test the null hypothesis that oestrogen containing continuous combined hormone replacement therapy (HRT) would not affect the hormone receptor expression (oestrogen and progesterone receptors-ER, PR) or markers of cell proliferation/apoptosis (Ki67 and Bcl-2) in endometrial polyps from postmenopausal women exposed and not exposed to HRT.

DESIGN

Immunohistochemical staining for ER, PR, Ki67 and Bcl-2 was performed on polyps obtained from two groups of postmenopausal women.

SETTING

Polyps were obtained from postmenopausal women attending an outpatient hysteroscopy clinic in a district general hospital (Bradford Royal Infirmary, UK).

POPULATION

Twenty-five postmenopausal women presenting with abnormal bleeding subsequently diagnosed with endometrial polyps (16 from women not exposed to HRT, 9 from women exposed to HRT).

METHODS

Semiquantitative immunohistochemistry was performed.

MAIN OUTCOME MEASURES

Significant differences or correlations in either hormone receptor expression or markers of cell proliferation/apoptosis between the two groups of polyps.

RESULTS

There were no significant differences for hormone receptor expression (ER and PR) between endometrial polyps exposed and not exposed to HRT. Bcl-2 expression was higher than Ki67 in both groups, but polyps from HRT users had increased levels reflecting decreased apoptosis in these polyps.

CONCLUSIONS

HRT has no demonstrable effect on polyp ER and PR expression. However, HRT does appear to inhibit apoptosis and cell proliferation in endometrial polyps, which may affect polyp growth.

Does tamoxifen therapy affect the hormone receptor expression and cell proliferation indices of endometrial polyps? An immunohistochemical comparison of endometrial polyps from postmenopausal women exposed and not exposed to tamoxifen

OBJECTIVE

This study set out to test the null hypothesis that tamoxifen therapy would not affect the hormone receptor expression (oestrogen and progesterone receptors-ER and PR) or markers of cell proliferation/apoptosis (Ki67 and Bcl-2) of endometrial polyps from postmenopausal women exposed and not exposed to tamoxifen.

METHODS

Endometrial polyps were prospectively obtained from women presenting with abnormal bleeding attending an out-patient hysteroscopy clinic who subsequently underwent endometrial polypectomy (16 from postmenopausal women not exposed to tamoxifen, 9 from women exposed to tamoxifen). Immunohistochemical staining for ER, PR, Ki67 and Bcl-2 was performed on polyps from both groups of women. Non-parametric statistical analysis was used (Mann-Whitney and Spearmans rank correlation).

RESULTS

Endometrial polyps from tamoxifen users had significantly lower oestrogen receptor but increased progesterone receptor and Bcl-2 expression. There were no significant differences for proliferation markers (Ki67) between postmenopausal endometrial polyps exposed and not exposed to tamoxifen.

CONCLUSIONS

Tamoxifen has a significant affect on hormone receptor expression and markers of apoptosis in endometrial polyps. The results support the hypothesis that tamoxifen promotes polyp growth by inhibiting apoptosis. The mechanism for this does not appear to be oestrogen receptor mediated.

Cancer of the endometrium: current aspects of diagnostics and treatment

Background

Endometrial cancer represents a tumor entity with a great variation in its incidence throughout the world (range 1 to 25). This suggests enormous possibilities of cancer prevention due to the fact that the incidence is very much endocrine-related, chiefly with obesity, and thus most frequent in the developed world. As far as treatment is concerned, it is generally accepted that surgery represents the first choice of treatment. However, several recommendations seem reasonable especially with lymphadenectomy, even though they are not based on evidence. All high-risk cases are generally recommended for radiotherapy.

Methods

A literature search of the Medline was carried out for all articles on endometrial carcinoma related to diagnosis and treatment. The articles were systematically reviewed and were categorized into incidence, etiology, precancerosis, early diagnosis, classification, staging, prevention, and treatment. The article is organized into several similar subheadings.

Conclusions

In spite of the overall good prognosis during the early stages of the disease, the survival is poor in advanced stages or recurrences. Diagnostic measures are very well able to detect asymptomatic recurrences. These only seem justified if patients' chances are likely to improve, otherwise such measures increases costs as well as decrease the patients' quality of life. To date neither current nor improved concepts of endocrine treatment or chemotherapy have been able to substantially increase patients' chances of survival. Therefore, newer concepts into the use of antibodies e.g. trastuzumab in HER2-overexpressing tumors and the newer endocrine compounds will need to be investigated. Furthermore, it would seem highly desirable if future studies were to identify valid criteria for an individualized management, thereby maximizing the benefits and minimizing the risks.

The effects of tamoxifen on the female genital tract

Tamoxifen is an effective and relatively non-toxic compound used in palliative and adjuvant treatment of breast cancer. More recently its preventive role in breast cancer has also been demonstrated. However, tamoxifen use is related to some increase in the risk of endometrial cancer and to a significant rise in the incidence of benign endometrial pathologies. The activity of tamoxifen against breast cancer is mainly achieved by blocking the oestrogen receptor, whereas the effect of this compound on the female genital tract is mostly related to its agonistic properties. Despite numerous studies no effective methods of tamoxifen-user surveillance have been developed and currently no active screening for endometrial cancer, apart from yearly gynaecological examination, is recommended in these patients. In other parts of the genital tract, tamoxifen increases the risk of some benign conditions and may cause difficulties in the interpretation of cervical smears. Further studies are warranted to develop more effective surveillance and methods decreasing the detrimental effects of tamoxifen on the female genital tract.

The early response of the postmenopausal endometrium to tamoxifen: expression of estrogen receptors, progesterone receptors, and Ki-67 antigen

OBJECTIVE

To enlighten the early response of endometrium to tamoxifen by assessing the expression of estrogen receptors, progesterone receptors, Ki-67, and the histological response in endometria from normal postmenopausal women treated for 21 days with tamoxifen.

DESIGN

A total of 40 women, scheduled to undergo vaginal hysterectomy because of uterine prolapse, were randomly assigned to the tamoxifen group (20 mg/day; 20 women) or the control group (20 women). Samples were obtained from the upper and the lower thirds of the uterine cavity. Standard immunohistochemical staining of estrogen and progesterone receptors and of Ki-67 was performed on frozen sections. Staining was assessed using semiquantitative immunoreactivity scores.

RESULTS

Simple endometrial hyperplasia was diagnosed in 18 of the 20 samples exposed to tamoxifen compared with only 2 of the 20 controls ( P< 0.0005). Staining was increased in both the epithelium and stroma in the tamoxifen samples, a difference that was significant for estrogen receptors in glandular epithelium (180 +/- 80 v 110 +/- 110; P< 0.05). Also, Ki-67 antigen was expressed more frequently in both glandular epithelium ( P< 0.05) and stroma ( P< 0.05) in the tamoxifen samples.

CONCLUSIONS

Tamoxifen rapidly up-regulated the cell proliferation markers, an effect that was associated with enhanced growth as confirmed by increased expression of estrogen receptors and Ki-67, in addition to a high incidence of glandular hyperplasia.