Estrogen receptor polymorphisms in tamoxifen-treated women with breast cancer.

In postmenopausal women with estrogen receptor (ER)-positive breast cancer, long-term tamoxifen administration has proved beneficial after surgical treatment and subsequent chemotherapy. One of the major adverse effects of tamoxifen is the development of endometrial pathology (polyps, endometrial hyperplasia and endometrial cancer). PvuII and XbaI polymorphisms of the estrogen receptor-alpha gene (ERalpha) and RsaI and AluI polymorphisms of the estrogen receptor-beta gene (ERbeta) have been associated with breast cancer. Thus the present study aimed to identify whether ER gene polymorphisms are associated with breast cancer stage or endometrial responsiveness to long-term tamoxifen treatment in 87 postmenopausal, tamoxifen-treated women with ER-positive breast cancer. The mean age of the patients was 58.7 +/- 4.7 years and the mean duration of tamoxifen treatment was 3.9 +/- 1.1 years. At diagnosis, the stage of breast cancer was determined as follows: 29 women (32%) at Stage I, 49 (58%) at Stage II and 9 (10%) at Stage III. The frequency distributions of the estrogen receptor polymorphisms in all women with breast cancer were not different from those predicted by the Hardy-Weinberg equilibrium hypothesis (p > 0.10). None of the ER polymorphisms studied was linked to either the presence of endometrial pathology or the stage of breast cancer.     

Protein kinase C alpha expression is inversely related to ER status in endometrial carcinoma: possible role in AP-1-mediated proliferation of ER-negative endometrial cancer

OBJECTIVE: Tamoxifen is the most widely used antiestrogen to treat all stages of estrogen-receptor (ER)-positive breast cancers. However, tamoxifen acts as a partial estrogen in the uterus and is known to increase the risk of endometrial cancer by two- to threefold. Recent evidence indicates that there is a connection between tamoxifen resistance and activation of the activator protein-1 (AP-1) pathway. We have previously reported a possible role for overexpression of protein kinase C alpha (PKCalpha), an upstream activator of the AP-1 pathway, in hormone-independent breast cancer and antiestrogen-stimulated endometrial tumors. We hypothesize that alterations of the PKC isozyme profile of endometrial carcinomas are similar to that of hormone-independent breast cancer and determine whether specific PKC isozyme alterations correlated with known clinicopathological features of endometrial cancer. METHODS: The PKC isozyme profile of endometrial carcinomas from 42 patients who were not previously exposed to antiestrogens was examined by Western blot. The relationship between PKC isozyme expression and key prognostic factors for endometrial carcinoma including hormone receptor status, tumor grade, stage, size, and depth of myometrial invasion was examined using the Spearman's rho correlation coefficient. RESULTS: As previously found in breast cancers, PKCalpha and estrogen receptor alpha (ERalpha) expression are inversely related (r(s) = -0.35, P = 0.046). We report significant inverse correlations among ER/progesterone receptor (PR) expression and tumor grade (r(s) = -0.49, P = 0.001 and r(s) = -0.44, P = 0.004, respectively), ER, and depth of myometrial invasion (r(s) = -0.40, P = 0.009). There were no other significant correlations between PKC isozyme expression and other key prognostic factors examined. CONCLUSION: This study indicates that, similar to what was previously observed in breast cancer, PKCalpha and ER expression is inversely related in endometrial cancer. PKCalpha expression may be a useful prognostic indicator in endometrial cancers. A model is offered which describes the putative role of PKCalpha overexpression in activation of the AP-1 pathway and increased proliferation of ER negative endometrial cancers.     

Molecular genetic characterization of tamoxifen-associated endometrial cancer

OBJECTIVES: The non-steroidal, selective estrogen receptor modulator tamoxifen is currently the most extensively used hormonal agent for the prevention and treatment of estrogen receptor-positive breast cancer. Epidemiologic studies and clinical trials have shown an increased risk of endometrial cancer with tamoxifen exposure; however, few studies have examined these tumors on a molecular level. We sought to elucidate the molecular genetic alterations found in tamoxifen-associated endometrial cancer. METHODS: Twenty-nine breast cancer patients with a history of tamoxifen use who subsequently developed endometrial cancer were retrospectively identified and matched for endometrial histologic subtype and grade to 29 endometrial cancers from breast cancer patients never exposed to tamoxifen. Endometrial tumor tissue was microdissected and genomic DNA extracted for each case. Direct DNA sequencing of the most commonly mutated genes in sporadic endometrial cancer, PTEN, K-RAS, TP53, and CTNNB1, was performed in addition to microsatellite instability (MI) studies. Fisher's Exact Test was utilized for statistical analyses. RESULTS: Of 29 tamoxifen-associated cancers, 10 (34.5%) contained PTEN mutations compared to 13 (44.8%) of the non-tamoxifen-associated cancers (P = 0.59). All PTEN mutations were found in tumors with endometrioid histology, reflecting what is seen in sporadic endometrial cancers. Mutations of K-RAS, TP53, and microsatellite instability were present in similar frequencies between the two breast cancer groups, and moreover, these were similar to mutational frequencies found in sporadic endometrial cancer. CONCLUSION: Tamoxifen and non-tamoxifen-associated endometrial carcinomas arising in women with breast cancer contain similar genetic alterations to those of sporadic endometrial carcinomas.     

Uterine side effects of treatment with tamoxifen

OBJECTIVE: To assess a causal the relationship between endometrial lesions and tamoxifen therapy in patients with breast cancer. DESIGN: Prospective longitudinal study and cross-sectional study. SETTING: Cancer prevention unit at Basurto Hospital, Bilbao. POPULATION AND METHODS: Three populations of breast cancer were studied: 43 before the beginning of tamoxifen; 78 after 5-72 months of tamoxifen, and 34 before tamoxifen and after 12-24 months of tamoxifen treatment (PAIRED GROUP). All of them were systematically studied with CO(2) diagnostic hysteroscopy and endometrial biopsy by the same clinician. RESULTS: Before tamoxifen, the following endometrial lesions were detected: endometrial polyps 9.3%; endometrial cysts 16.3%; synechiae 11.6%. In the paired group the ingestion of tamoxifen shows a direct causal effect with a significant increase in endometrial polyps (11.8% vs. 29.4%; OR=13; CI=7.9-18.1), in endometrial cysts (17.7% vs. 55.9%; OR=7.5; CI=5. 9-9.1) and in synechiae (14.7% vs. 35.5%; OR=8; CI=4.7-11.3). In the group under tamoxifen for 5-72 months, one endometrial carcinoma was detected. CONCLUSIONS: Breast cancer patients have a number of endometrial lesions before undergoing any hormonal therapy. Tamoxifen significantly increased benign endometrial lesions, usually after less than one year of treatment. No cases of endometrial carcinoma was found in our series of 34 patients with 1-2 years of tamoxifen treatment, and 1/78 in patients with 5-72 months of tamoxifen.     

Subsequent endometrial carcinoma with adjuvant tamoxifen treatment in Japanese breast cancer patients

Abstract. Nishimura N, Hachisuga T, Saito T, Kawarabayashi T. Subsequent endometrial carcinoma with adjuvant tamoxifen treatment in Japanese breast cancer patients.
This study aimed to detail the clinicopathologic features of endometrial carcinomas that developed in Japanese patients receiving adjuvant tamoxifen treatment for breast cancer patients. Ten endometrial carcinomas in tamoxifen-treated breast cancer patients were collected from two medical centers. The endometrial carcinomas included two stage Ia, four stage Ib, two stage Ic and two stage IIIc. Three tumors were Grade 1, six were Grade 2, and one was Grade 3. The tumor was limited to the endometrium in two cases. Myometrial invasion was limited to the inner half of the myometrium in five cases and involved the outer half in three. A mild degree of lymphovascular space invasion was identified in five cases. Deep cervical invasion was recognized in one case. The cell types comprised nine endometrioid adenocarcinomas and one serous carcinoma. Five of eight postmenopausal endometrial carcinomas were associated with polypoid endometrial lesions composed of cystically dilated atrophic and proliferative glands widely separated by fibrotic stroma. Two patients with retroperitoneal lymph node metastases died of endometrial cancer. One patient developed a contralateral breast cancer during tamoxifen treatment. No patient died of breast cancer. We did not demonstrate a higher frequency of either high-grade tumors or unfavorable histologic subtypes in tamoxifen-treated Japanese breast cancer patients.     

Precancerous lesion of the endometrium and endometrial morphology in patients with tamoxifen therapy

The endometrioid type of endometrial adenocarcinoma,(type 1-carcinoma) is estrogen-dependent and frequently associated with endometrial hyperplasia. The nomenclature of these hyperplasias is currently under discussion. The highest risk for metachronous carcinoma is associated with atypical hyperplasia of the endometrium as detected in fractional curettings. In postmenopausal patients treatment should consist of abdominal hysterectomy. The so-called type 2-carcinomas, serous-papillary and clear-cell type, do not demonstrate a similar association with precursor lesions. Pathological findings in patients treated with Tamoxifen include endometrial atrophy and fibro-cystic endometrial polyps, sometimes with cellular metaplasias. Patients with breast cancer and tamoxifen treatment have an increased risk of endometrial carcinoma. In some of these patients it could be argued whether the carcinoma has developed in a proceeding endometrial hyperplasia.     

Gynaecological Complications of Women Treated with Tamoxifen for Breast Cancer

Summary: We present 6 cases illustrating some of the gynaecological complications associated with tamoxifen treatment of women with breast cancer. The first 2 represent cases of myometrial hypertrophy secondary to tamoxifen use, a postmenopausal woman and a premenopausal women with recurrent carcinoma of the breast. The third is a case of probable ovulation induction in a perimenopausal woman with recurrent breast cancer who was commenced on tamoxifen 20 mg daily. The other 3 cases illustrate some of the endometrial effects associated with tamoxifen therapy in women with a history of breast cancer, namely cystic glandular hyperplasia, endometrial polyps and endometrial cancer.     

An unusual type of endometrial cancer, related to tamoxifen?

Tamoxifen, which is increasingly being used in breast cancer patients, has been associated with an elevated frequency of endometrial carcinoma. To our knowledge not a single case of uterine serous papillary carcinoma (USPC) has been documented during tamoxifen treatment. No conclusions as to a causal relationship are yet being made, but if it is due to tamoxifen, we should advise a strategy for prevention, because this subtype is not as curable as endometrioid carcinoma.     

DNA-content in endometrial carcinoma of tamoxifen-treated breast cancer patients

DNA measurements and histopathologic evaluation were performed in 17 patients treated with adjuvant tamoxifen for early breast cancer and who developed endometrial carcinoma during or after the tamoxifen therapy. The tumors were exclusively characterized by euploid DNA content except for two cases, one mixed mesodermal sarcoma, a highly malignant and rare tumor, and one adenocarcinoma. Although the use of adjuvant tamoxifen therapy most likely enhances the risk of developing endometrial carcinoma, the beneficial effects of adjuvant breast cancer treatment is of well-known clinical importance. The hazards of giving long-term tamoxifen seem to be low since the endometrial tumors were associated with low-grade malignancy and euploid DNA pattern.     

p27 and cyclin D1 abnormalities in uterine papillary serous carcinoma

OBJECTIVE: The expression status of p27 and cyclin D1 was examined in 21 uterine papillary serous carcinoma (UPSC) specimens to determine the role of these genes in the development of this disease. The status of p53, p16, Rb, and K-ras was also determined in these tissues so that a marker profile for UPSC could be compared with the published marker profile for other forms of endometrial and ovarian cancer. METHODS: Immunohistochemistry was performed on 21 UPSC tissue sections to determine the expression status of p27, cyclin D1, p53, p16, and Rb. K-ras mutations were identified by restriction fragment length polymorphism analysis of DNA isolated from the UPSC sections. RESULTS: All specimens displayed at least one molecular abnormality. A high incidence of p27 alterations were observed, with reduced p27 expression measured in 16 of 21 (76%) tumors, followed by p53 alterations observed in 13 of 21 (62%) tumors. The p27 abnormalities occur at an early stage of the disease, with 63% (5/8) of Stage I cases displaying reduced p27 expression. Cyclin D1 overexpression was observed in 4 of 21 (19%) specimens, whereas p16, Rb, and K-ras abnormalities were each observed in 2 of 21 specimens (10%). Both K-ras mutations were at codon 12. The p16 and Rb abnormalities coexisted in the same specimens. CONCLUSION: UPSC tumors display a high incidence of p27 abnormalities, suggesting that p27 abnormalities play an important role in the development of this disease. Our results also indicate that cyclin D1 overexpression is involved in the development of a small number of UPSC cases. A comparison of our results with reports by other authors suggests that UPSC shares molecular marker alterations with both ovarian cancer and endometrioid adenocarcinoma.     

Estrogen receptor expression in an endometrial stromal sarcoma after tamoxifen therapy

INTRODUCTION: Several cases of low-grade endometrial stromal sarcomas in women with breast cancer have been reported to be associated with tamoxifen therapy. Estrogen receptor expression has been used to characterize the partial estrogenic action of tamoxifen on the endometrium and has been found in tamoxifen-associated endometrial pathologies. CASE: A low-grade endometrial stromal sarcoma in a woman with a history of breast cancer treated with adjuvant tamoxifen is presented. Steroid receptor studies performed on the tumor were negative for estrogen and positive for progesterone. CONCLUSION: The absence of estrogen receptor expression suggests that endometrial stromal sarcomas are not necessarily caused by the estrogenic properties of tamoxifen.     

Does tamoxifen use affect prognosis in breast cancer patients who develop endometrial cancer?

OBJECTIVE: The use of tamoxifen to prevent breast cancer and decrease recurrence is not controversial. However, the effect that tamoxifen may have in women with a history of breast cancer in whom endometrial cancer develops is unclear. The purpose of this study was to estimate whether a history of tamoxifen use is a prognostic factor for such patients. METHODS: Between 1990 and 2002, patients seen at The University of Texas M. D. Anderson Cancer Center with a history of breast cancer who developed endometrial cancer were identified. Medical records were reviewed to identify clinical, pathologic, and outcome information. RESULTS: Eighty-nine patients with a history of breast cancer in whom endometrial carcinoma developed were identified. Fifty-two percent (46/89) had a history of tamoxifen use (median duration 48 months; range 2-120 months). There were no significant differences in the clinical or pathologic features between tamoxifen users and nonusers. A history of tamoxifen use was associated with a shorter interval from breast cancer to endometrial cancer diagnosis (77.2 versus 121.3 months for nonusers; P =.01). There was no significant difference in overall survival between tamoxifen users and nonusers (39.2 months versus 48.3 months, P =.27), and there was no difference in endometrial cancer-specific survival duration between tamoxifen users and nonusers (55.7 versus 51.0 months, P =.92). CONCLUSION: Among tamoxifen users, the interval from breast cancer to endometrial cancer diagnosis was significantly shorter than that in nonusers. In this cohort, a history of tamoxifen use was not associated with a worse overall or disease-specific survival.     

Failure of megestrol acetate to reverse tamoxifen induced endometrial neoplasia: two case reports

Abstract. Rose PG, Brandewie EV, Abdul-Karim FW. Failure of megestrol acetate to reverse tamoxifen induced endometrial neoplasia: two case reports.
Tamoxifen's agonist effect on the endometrium has been associated with an increased incidence of endometrial carcinoma. It has been suggested that this agonist effect may be averted by the concomitant use of a progestational agent. We report two patients with breast cancer receiving tamoxifen who developed endometrial carcinoma and atypical endometrial hyperplasia, respectively. In one patient, this occurred despite the use of concomitant megestrol acetate. In the other patient, tamoxifen-associated endometrial hyperplasia persisted and progressed despite cessation of tamoxifen and initiation of megestrol acetate therapy. These cases may have implications for strategies to avert tamoxifen induced endometrial neoplasia.     

绝经后乳腺癌患者服用他莫昔芬发生子宫内膜息肉危险因素的探讨

目的:探讨绝经后因乳腺癌服用他莫昔芬(TAM)与子宫内膜息肉发生的相关性。方法:随诊了46例绝经后服用TAM超过6个月的妇女,其中22例经宫腔镜手术及内膜病理证实为内膜息肉(A组),24例宫腔镜检查未发现息肉(B组)。比较2组服用TAM的时间、剂量,经阴道超声波(TVS)检查的结果,并分析与子宫内膜癌相关的危险因素。结果:息肉组妇女的体重明显重于非息肉组(P=0.013),且比非息肉组服用TAM的时间长,TAM的累计剂量增加(P值均为0.002)。经阴道超声波检查示息肉组子宫内膜增厚或者宫内异常回声的发生率明显高于非息肉组(P=0.019)。结论:肥胖,长期服用TAM超过2年或累计剂量超过15g是绝经后妇女服用TAM发生子宫内膜息肉的高危因素。TVS提示内膜增厚或者宫内异常回声有诊断价值,可作为预测内膜息肉发生的指标。     

The prognostic value and clinical utility of estrogen and progesterone receptors in endometrial carcinoma

In the United States, endometrial carcinoma is the most common gynecologic malignancy, and accounts for 4,900 deaths per year in the United States. While this disease has relatively good cure rates, there is motivation to describe other determinants, which may help in the treatment of this disease. Attempts have been made to correlate hormone receptor status with disease-free intervals and survival in patients with endometrial carcinoma. The weight of evidence seems to support that of the two hormone receptors, progesterone is the more significant predictor of patient outcome. If hormone receptors are to be used in the management of endometrial carcinoma, they should be determined by immunohistochemistry. In the adjuvant setting, patients with progesterone positive tumors are more amenable to treatment with progestational agents than are patients with receptor negative tumors. Future areas of research include the use of tamoxifen and selective estrogen receptor modulators in the chemoprevention and treatment of endometrial carcinoma.     

Ovarian cysts in postmenopausal tamoxifen-treated breast cancer patients with endometrial thickening detected by transvaginal sonography

OBJECTIVE: To investigate the frequency of ovarian cysts in tamoxifen-treated postmenopausal breast cancer patients with endometrial thickening detected by transvaginal sonography. METHODS: Medical records and transvaginal sonographies of 38 postmenopausal women treated for breast cancer with adjuvant tamoxifen therapy who had undergone endometrial sampling due to abnormal endometrial thickness were reviewed retrospectively. RESULTS: During the study period five of 38 tamoxifen-treated postmenopausal patients (13.2%) had ovarian cysts. The mean tamoxifen treatment interval of the patients with an ovarian cyst was 22.4 +/- 18.4 months (p = 0.17). The mean endometrial thickness of the patients with an ovarian cyst was 12.6 +/- 5.9 mm (p = 0.17). Endometrial biopsy detected six cases of abnormal endometria, including endometrial carcinoma (n = 1), endometrial polyp (n = 1) and simple endometrial hyperplasia without atypia (n = 4). Three patients with ovarian cysts underwent laparatomy revealing simple cysts on histopathological examination. Two patients with ovarian cysts declined laparatomy and are currently under follow-up. CONCLUSION: Ovarian cysts a common side-effect of tamoxifen treatment in postmenopausal tamoxifen-treated breast cancer patients. Transvaginal sonography should be performed to detect any concomitant endometrial pathology.     

Tamoxifen and giant endometrial polyps

Tamoxifen is a synthetic non-steroid anti-estrogen that has been used effectively for several years in the adjuvant treatment of breast cancer. Although its therapeutic effect is due to its anti-estrogenic properties, the drug also shows modest type B estrogen-receptor agonist activity during the menopausal period in which estrogens are at a low level. Owing to the fall in estrogen levels in menopause, tamoxifen provokes an up-regulation of both estrogen and progesterone receptors at an endometrial tissue is a direct consequence of this. This proliferation, which is the result of an inappropriate response of the basal layer and the basis for the onset of hyperplasia and polyps in the tissue. At standard therapeutic dosages, tamoxifen in postmenopausal women is associated with the onset of alterations in the vaginal and endometrial epithelium. Cases of endometrial hyperplasia, endometrial polyps, adenomyosis, endometriosis and fibromyomas are described in the literature. Endometrial polyps represent the most common pathology associated with TAM in women with previous breast cancer in menopause. The estrogenic stimulus to polyps following TAM treatment may be considerable, resulting in their growth to sizeable proportions, causing metrorrhagia and suspected neoplastic pathology. Two cases of patients receiving adjuvant treatment with tamoxifen for previous breast cancer, who presented two giant endometrial polyps of uncommon dimension, are reported.     

Carcinosarcoma, endometrial intraepithelial carcinoma and endometriosis after tamoxifen therapy in breast cancer

The fourth case of heterologous mesodermal tumour of the uterine corpus, that developed, years following tamoxifen therapy for breast cancer in a postmenopausal woman with no previous pelvic irradiation, is presented with coincidental endometriosis and endometrial intraepithelial carcinoma. This coincidence after tamoxifen treatment appears to be an indication for the possible carcinogenic potency of tamoxifen.     

Update on clinical role of tamoxifen

PURPOSE OF REVIEW: Breast cancer is the most common malignancy amongst women in the United States and decreased mortality over the past decade has been attributed to a combination of screening and adjuvant therapies. There has been a resurgence of interest in hormonal therapies and this article discusses the clinical status of tamoxifen in the context of emerging alternative agents for treatment and prevention of breast cancer. RECENT FINDINGS: Tamoxifen has served as a prototype for the development of selective estrogen receptor modulators at the laboratory-clinical interface. Molecular technologies have permitted elucidation of mechanisms for tissue specific action and led to newer selective estrogen receptor modulators with potentially greater antitumour efficacy and attenuated uterotrophic profile. Publications over the past 12 months have emphasized the risks of thromboembolism and endometrial carcinoma associated with tamoxifen use which has accelerated application of other hormonal agents for treatment of advanced disease and as neoadjuvant therapy. This article reviews the current role of tamoxifen in the treatment of early and advanced breast cancer together with its potential for chemoprevention. Models for quantitative risk assessment are being developed to identify women for whom chemoprotection is justified. SUMMARY: Recent data showing a survival advantage for the aromatase inhibitor letrozole compared with tamoxifen in the advanced setting and improvement in disease-free survival for the aromatase inhibitor anastrozole versus tamoxifen as adjuvant treatment may herald a major shift in standard first-line endocrine therapies for both advanced and early disease and ultimately chemoprevention of breast cancer. Other agents including newer SERMs and pure antiestrogens are undergoing phase III clinical trials and future endocrine and biological therapies are likely to include more selective and targeted therapies, which may be efficacious in both hormone-sensitive and receptor-negative disease.     

Endometrial pathology of 104 postmenopausal breast cancer patients treated with tamoxifen

OBJECTIVE: To investigate the effects of tamoxifen on the endometrium in postmenopausal breast cancer patients. METHODS: Endometrial thickness was measured by transvaginal sonography and endometrial biopsies were done in 104 postmenopausal breast cancer cases who were treated with tamoxifen. Histopathologic findings were discussed. RESULTS: Mean endometrial thickness was 11.7+/-5.9 mm and duration of tamoxifen administration was 35.3 months. Four endometrial cancers, 17 endometrial hyperplasias, 25 proliferative endometrium, 5 endometrial polyps in the endometrial biopsies. We observed atrophic endometrium in 53 of the cases. Only one case with endometrial polyps was observed as a premalignant lesion when the endometrium was less than 5 mm, 51% of the cases had thicker endometrium (more than 10 mm) and 32% of these cases had malignant and premalignant endometrium. We found a significant correlation with the duration of tamoxifen and age (p<0.05). One hundred and two of our cases were asymptomatic; only 2 out of 4 endometrial cancer cases had vaginal spotting. A significant relation was noticed between endometrial thickness and duration of tamoxifen treatment (p=0.025). CONCLUSION: It was concluded that positive endometrial findings and endometrial thickness were due to continuous unopposed tamoxifen treatment and our findings support the hypothesis that tamoxifen increases the risk of endometrial carcinoma and premalignant changes.