Ultrasonographic measurement of endometrial changes following discontinuation of tamoxifen treatment in postmenopausal breast cancer patients

Endometrial pathology in breast cancer patients: Effect of different treatments on ultrasonographic, hysteroscopic and histological findings

Breast cancer patients have an increased risk of endometrial pathology. To investigate whether the incidence of endometrial abnormalities and their clinicopathological features were affected by receiving tamoxifen (TAM), non-steroidal aromatase inhibitors (AIs) or no treatment (NT), 333 peri/postmenopausal breast cancer patients, who were referred to the Department of Gynecological, Obstetrical Sciences and Reproductive Medicine for gynecological assessment, were reviewed retrospectively. Transvaginal ultrasonographic (TVUS), hysteroscopic and histological findings were investigated. Endometrial histological findings included: atrophy in 61, 94.3 and 55.6% of cases in the TAM, AIs and NT groups, respectively; polyps in 30.9, 31.4 and 42.2% of cases in the TAM, AIs and NT groups, respectively; hyperplasia in 3% of patients in the TAM group and 11.1% of patients in the NT group; and cancer in 3.8% of cases in the TAM group and 11.1% of cases in the NT group. There was a significant correlation between the duration of TAM treatment and the severity of endometrial pathology. In all groups, there was a significant correlation between hysteroscopic and histological findings with regard to the diagnosis of endometrial atrophy, polyps, hyperplasia and cancer (P<0.001). In conclusion, these data revealed that there was a higher incidence of endometrial pathology in the NT group compared with the TAM group, which was significant for endometrial hyperplasia and cancer. The chance of developing high-risk histological subtypes of endometrial cancer was independent of TAM use. Lastly, although there was no significant difference in recurrent vaginal bleeding and mean endometrial thickness between the TAM and AIs groups, patients receiving AIs did not exhibit hyperplastic, dysplastic or neoplastic changes in the endometrium. This study indicates that breast cancer patients require screening for endometrial pathology; TVUS alone is useful in asymptomatic patients, however, in patients where the endometrial line is irregular or its thickness is >3 mm, hysteroscopy with directed biopsy is the appropriate diagnostic method.

Long-term endometrial effects in postmenopausal women with early breast cancer participating in the Intergroup Exemestane Study (IES)--a randomised controlled trial of exemestane versus continued tamoxifen after 2-3 years tamoxifen

BACKGROUND

The antiestrogen tamoxifen may have partial estrogen-like effects on the postmenopausal uterus. Aromatase inhibitors (AIs) are increasingly used after initial tamoxifen in the adjuvant treatment of postmenopausal early breast cancer due to their mechanism of action: a potential benefit being a reduction of uterine abnormalities caused by tamoxifen.

PATIENTS AND METHODS

Sonographic uterine effects of the steroidal AI exemestane were studied in 219 women participating in the Intergroup Exemestane Study: a large trial in postmenopausal women with estrogen receptor-positive (or unknown) early breast cancer, disease free after 2-3 years of tamoxifen, randomly assigned to continue tamoxifen or switch to exemestane to complete 5 years adjuvant treatment. The primary end point was the proportion of patients with abnormal (> or =5 mm) endometrial thickness (ET) on transvaginal ultrasound 24 months after randomisation.

RESULTS

The analysis included 183 patients. Two years after randomisation, the proportion of patients with abnormal ET was significantly lower in the exemestane compared with tamoxifen arm (36% versus 62%, respectively; P = 0.004). This difference emerged within 6 months of switching treatment (43.5% versus 65.2%, respectively; P = 0.01) and disappeared within 12 months of treatment completion (30.8% versus 34.7%, respectively; P = 0.67).

CONCLUSION

Switching from tamoxifen to exemestane significantly reverses endometrial thickening associated with continued tamoxifen.

Evaluation of endometrial thickness in hormone receptor positive early stage breast cancer postmenopausal women switching from adjuvant tamoxifen treatment to anastrozole

Evaluation of endometrial thickness by transvaginal ultrasonography (TVUS) in postmenopausal estrogen receptor positive breast cancer patients treated with anastrozole after tamoxifen therapy. This study included 70 postmenopausal estrogen receptor positive breast cancer patients who switched to anastrozole after tamoxifen; patients had endometrial thickness >4mm and no endometrial malignancy. Endometrial thickness was measured after anastrozole treatment. Endometrial thickness during anastrozole therapy was lower than after tamoxifen therapy (p<0.001); the mean reduction in endometrial thickness was 4.5mm (+/-3.0). Cystic endometrial appearance was more frequent in patients under tamoxifen than in those under anastrozole (p<0.001). Duration of tamoxifen therapy was not correlated to the endometrial thickness at the time of its suspension. Duration of tamoxifen therapy and endometrial thickness at the time of tamoxifen suspension was correlated to the relative reduction of endometrial thickness during anastrozole therapy. Anastrozole reverses tamoxifen-induced increased endometrial thickness and sonographic endometrial cystic appearance.

Long-term follow-up of postmenopausal breast cancer patients following discontinuation of tamoxifen therapy

BACKGROUND

There is a need to evaluate the extent of endometrial pathologies that might develop in postmenopausal breast cancer patients following discontinuation of tamoxifen (TAM) therapy.

METHODS

The medical records of 153 postmenopausal breast cancer patients who remained untreated following discontinuation of tamoxifen therapy were evaluated for various clinical features, for endometrial thickness measurements, as detected by transvaginal ultrasonography, and for various endometrial pathologies detected. The last endometrial thickness measurement performed before discontinuation of tamoxifen was compared with endometrial thickness measured following discontinuation of tamoxifen.

RESULTS

Patients were followed for 37.5+/-31.3 months. There was a gradual and significant decrement of endometrial thickness measured at the last ultrasonographic study performed before cessation of tamoxifen, compared to that observed in all four ultrasonographic studies performed following discontinuation of tamoxifen (P=0.001). Endometrial thickness gradually and significantly decreased in correlation with the time intervals of the four ultrasonographic studies performed following discontinuation of tamoxifen (P=0.001). Overall, 40 hysteroscopies were performed in 38 (24.8%) patients. No tissue was obtained in 18 (11.8%) patients. Overall endometrial pathologies were diagnosed in 22 (14.4%) patients. Benign endometrial polyps were the most frequent endometrial pathology recovered: 17 (11.1%) patients. No endometrial malignancy was diagnosed. The rate of endometrial pathologies considerably decreased with the extension of time following discontinuation of tamoxifen therapy.

CONCLUSIONS

Long-term follow-up of postmenopausal breast cancer patients who remained untreated following discontinuation of TAM therapy did not reveal any malignant endometrial pathology. Only few benign endometrial pathologies were diagnosed, which became fewer in time.

Aromatase inhibitors reverse tamoxifen induced endometrial ultrasonographic changes in postmenopausal breast cancer patients

OBJECTIVE

Aromatase inhibitors may decrease endometrial thickness in breast cancer patients previously having short-term tamoxifen treatment. There is a necessity to find out if aromatase inhibitors can also decrease endometrial thickness in patients previously treated with long-term tamoxifen treatment.

METHODS

Prospective comparison of the last ultrasonographic endometrial thickness measurement taken before discontinuation of long-term tamoxifen treatment in 36 postmenopausal breast cancer patients, with further measurements, performed following aromatase inhibitors administration.

RESULTS

There was a significant decrement of endometrial thickness, following 36.2 +/- 16.8 months of tamoxifen treatment, from a mean value of 9.1 +/- 5.8 mm, measured at the last ultrasonographic measurement performed before discontinuation of tamoxifen treatment, down to a mean value of 6.0 +/- 5.0 mm, measured following 5.8 +/- 5.8 months of aromatase inhibitors therapy (P = 0.001). A second ultrasonographic measurement performed in 8 patients following of additional 7.5 +/- 4.0 months of aromatase inhibitors treatment revealed further decrement of mean endometrial thickness to 4.8 +/- 2.1 mm (P = 0.002 compared to baseline). In 28 patients (77.8%), endometrial thickness was reduced following the administration of aromatase inhibitors, in four patients (11.1%) there was no change in endometrial thickness and four (11.1%) patients demonstrated an increase of endometrial thickness.

CONCLUSIONS

Aromatase inhibitors may reverse endometrial thickening induced by long-term tamoxifen treatment in postmenopausal breast cancer patients.

Changes in the sonographic appearance of the uterus after discontinuation of tamoxifen therapy

OBJECTIVE

The purpose of this study was to assess the duration of sonographically detected changes in the endometrium of women with a history of tamoxifen use.

METHODS

Patients with breast cancer who had a history of tamoxifen use and documented pelvic sonographic studies were identified by means of clinic databases in both the Section of Gynecological Oncology and the Section of Obstetrical and Gynecological Ultrasound, University of Chicago, between January 1, 1996, and March 30, 2004. Of the 99 patients who met study criteria, 34 had discontinued tamoxifen use before the sonographic evaluation. Each patient's age, gravity and parity, weight, ethnicity, duration and dose of drug use, interval from drug discontinuation until sonographic evaluation, and uterine pathologic findings were reviewed. Endometrial thickness as assessed by pelvic sonography was examined in relation to duration of tamoxifen use and time from discontinuation of the drug. Statistical analysis was performed with linear regression and mixed effect linear regression models.

RESULTS

Endometrial thickness increased with increasing duration of tamoxifen use at a rate of 0.75 mm/y. The mean endometrial thickness after approximately 5 years of tamoxifen use was 12 mm (range, 6-21 mm). After discontinuation of tamoxifen, endometrial thickness decreased by 1.27 mm/y.

CONCLUSIONS

Endometrial thickness as measured by pelvic ultrasound examination increases with the duration of tamoxifen use. After discontinuation of the drug, the measured thickness decreases but at a very slow rate.

The value of transvaginal ultrasonography in the prediction of endometrial pathologies in asymptomatic postmenopausal breast cancer tamoxifen-treated patients

OBJECTIVE

There is no established ultrasonographic endometrial cutoff value for the diagnosis of endometrial pathologies in asymptomatic postmenopausal tamoxifen (TAM)-treated patients. We attempted to seek the most accurate cutoff value.

MATERIALS AND METHODS

Multiple ultrasonographic cutoff points were evaluated by logistic regression analysis based on 279 patients who had transvaginal ultrasonographic examinations followed by endometrial histopathological analysis. Performance characteristics were calculated with correlation to the endometrial histological findings. We also calculated how many endometrial pathologies could have been left undiagnosed and the number of endometrial samplings, with different cutoff values, which could have been avoided.

RESULTS

There was a gradual increase in specificity and a gradual decrease in sensitivity of the ultrasonographic studies with the increase of endometrial thickness. More overall and more various endometrial pathologies were identified with the increase in cutoff values. The best cutoff value appeared to be 15 mm (sensitivity 37.9%, specificity 87.2%, positive predictive value 63.0%, and negative predictive value 70.2%). However, by avoiding performance endometrial sampling up to this cutoff value, 62.2% endometrial pathologies including 48 endometrial polyps, one case of endometrial hyperplasia with atypia, and one case of endometrial cancer may have been left undiagnosed. At the same time, endometrial sampling in 78.5% of cases may have been avoided.

CONCLUSION

In asymptomatic postmenopausal breast cancer tamoxifen-treated patients, the use of wider ultrasonographic endometrial cutoff values could be associated not only with the performance of fewer endometrial samplings, but also with a higher possibility of endometrial pathologies, including endometrial cancers, being left undiagnosed.

The value of sonohysterography in the prediction of endometrial pathologies in asymptomatic postmenopausal breast cancer tamoxifen-treated patients

BACKGROUND

The study evaluated the efficacy of sonohysterography in identifying endometrial pathologies in asymptomatic postmenopausal tamoxifen (TAM)-treated patients by evaluating its performance characteristics.

MATERIALS AND METHODS

Multiple assessments of sonohysterography evaluations of intrauterine mass diameter were evaluated by logistic regression analysis based on overall 85 patients (who had transvaginal ultrasonographic endometrial thickness of >/=8 mm) followed by hysteroscopy and endometrial histological findings. Performance characteristics were calculated with correlation to the endometrial histological findings.

RESULTS

The mean endometrial thickness was 14.6 +/- 6.2 mm, and the mean intrauterine mass diameter detected by SIS was 11.6 +/- 10.4 mm. There was a gradual decrease in sensitivity and gradual increase in specificity of the SIS studies with the increase in intrauterine mass diameter. False-negative and false-positive of SIS were 2.4% and 8.2%, respectively. ROC curve analysis of intrauterine mass revealed 5 mm as the best accurate cutoff value for the diagnosis of endometrial pathologies, with a sensitivity of 74.1%, specificity of 93.0%, and positive predictive value of 88.3% and negative predictive value of 84.2%. The risk of endometrial pathology was elevated by 1.37-fold, with any additional millimeter of diameter of the intrauterine mass. The mean diameter of the intrauterine mass gradually increased the greater the severity of the histological findings.

CONCLUSIONS

Sonohysterography improves the accuracy of diagnosis of intrauterine mass in asymptomatic postmenopausal tamoxifen-treated patients. The size of the intrauterine mass correlates with the severity of the endometrial pathology.

Significance of secondary ultrasonographic endometrial thickening in postmenopausal tamoxifen-treated women

BACKGROUND

Ultrasonography has a limited value in endometrial assessment for identification of endometrial pathologies in postmenopausal tamoxifen-treated patients.

METHODS

We compared the rate of endometrial pathologies and the mean +/- SD of endometrial thickness diagnosed after the first and second transvaginal ultrasonographic studies performed on 55 postmenopausal tamoxifen-treated patients with secondary endometrial thickening (Group I). This rate was also compared with 46 similar patients without secondary thickening (Group II). We also compared the mean +/- SD of endometrial thickness detected in various ultrasonographic studies, as well as various clinical features.

RESULTS

A significantly higher rate of endometrial pathologies, including two cases of endometrial cancer identified in gynecologically asymptomatic patients (3.6%), was diagnosed in Group I after the second study compared with the first study (52.7% and 9.1%, respectively; P = 0.001) and compared with those diagnosed after the second study in Group II (30.4%; P = 0.03). There was a significant increase (74.7 +/- 115%) in endometrial thickness after the second study compared with the first study performed on Group I (10.7 +/- 5.53 mm and 16.59 +/- 5.53 mm, respectively; P = 0.0001) and a significant difference in endometrial thickness demonstrated in the second study performed on Groups I and II (16.59 +/- 5.53 mm and 11.4 +/- 3.91 mm, respectively; P = 0.001). There were no significant differences in the time elapsed since the diagnosis of breast carcinoma and from the beginning of tamoxifen treatment to the performance of the first ultrasonographic study as well as the time elapsed between the first and second studies performed.

CONCLUSIONS

A significant increase (> 50%) in secondary endometrial thickening, measured ultrasonographically, in postmenopausal tamoxifen-treated patients, is associated with a high rate of endometrial pathologies, including endometrial cancer.

Postmenopausal bleeding: value of imaging

Endovaginal sonography in combination with HSG is an effective screening tool in evaluating patients with postmenopausal bleeding. Endovaginal sonography is highly sensitive for detecting endometrial carcinoma and can identify patients at low risk for endometrial disease obviating the need for endometrial sampling in this subgroup of patients. In patients with abnormal findings at sonography, a detailed morphologic analysis can be used to determine which patients can undergo blind endometrial sampling successfully versus those who would benefit from hysteroscopic guidance. In patients in whom endovaginal sonography and HSG are inadequate, MRI may provide additional information on the appearance of the endometrium, particularly in patients in whom endometrial sampling is difficult (eg, patients with cervical stenosis).

Tamoxifen, screening and new oestrogen receptor modulators

Tamoxifen is a selective oestrogen receptor modulator (SERM) with anti-oestrogenic properties in the breast and oestrogenic effects in tissues such as bone and the cardiovascular system. It is an excellent breast cancer drug for all stages of the disease. Its SERM profile makes it a valuable alternative to hormone replacement therapy, especially for women at high risk of breast cancer. Tamoxifen, however, increases the incidence of benign and malignant lesions of the uterus. Secondary prevention of these, early detection and treatment, is feasible but not cost-effective in breast cancer patients because potential endometrial risks do not outweigh beneficial effects in the breast. This may be different in healthy women with an as yet unknown benefit on breast cancer mortality. We review the literature on the importance of tamoxifen's endometrial lesions and balance available evidence on whether and how best to screen them. In a subset of tamoxifen users it seems advisable to assess the uterine cavity prior to intake with a yearly endometrial assessment as pointed out, starting 3 years after initiation of treatment. In most cases there is endometrial thickening on ultrasonographic assessment and additional tests such as hydrosonography or hysteroscopy are required to confirm an empty atrophic uterus as remains the case in most asymptomatic women on tamoxifen. Newer compounds, such as raloxifene, have a similar SERM profile to tamoxifen but are neutral on the uterus. This has recently been proven by 3 years of endometrial follow-up data. Longer endometrial safety will hopefully confirm these early findings. Whether other SERMs in development are better, and which of them is better for the breast, is to be demonstrated in ongoing studies.