False sonographic appearance of endometrial neoplasia in postmenopausal women treated with tamoxifen

Evaluation of endometrial thickness in breast cancer patients with tamoxifen treatment - Difference between 2-dimensional ultrasonography and elastosonography

OBJECTIVE

This study aimed to confirm the clinical significance of elastographic endometrium measurement in comparison with conventional ultrasonography for tamoxifen users with breast cancer.

MATERIALS AND METHODS

In this retrospective analysis, 98 women receiving tamoxifen as postoperative breast cancer treatment were included. Patient medical charts were reviewed, and related medical, obstetric, and gynecological information and histories relevant to breast cancer were evaluated. Patient clinical imaging data included endometrial thickness measurements using both conventional ultrasonography and elastography, and the differences between these two modalities in delta values were statistically analyzed along with possible influencing factors.

RESULTS

Endometrial thickness measured using 2-dimensional ultrasonography had a mean value of 5.81 mm (standard deviation [SD] = 3.09), and elastosonography showed a mean value of 3.07 mm (SD = 1.62). A paired t-test was conducted and a significant difference between them was confirmed (P-value <0.001). Logistic regression analysis revealed that age and duration of tamoxifen treatment significantly influenced the degree of difference between endometrial thickness measurements.

CONCLUSIONS

Elastosonography may be a more successful and useful tool for measuring actual endometrial thickness than generalized 2-dimensional ultrasonography. In clinical cases with limited use of elastosonography and consequent inability for thorough evaluation of endometrial thickness, practitioners should exercise caution in deciding whether or not to adopt invasive diagnostic procedures, such as endometrial curettage, especially for young patients of reproductive age or those with prolonged treatment of breast cancer with tamoxifen.

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.

Controversy about uterine effects and safety of SERMs: the saga continues

From the perspective of endometrial safety, there has been great controversy about what special management, if any, tamoxifen-treated patients should undergo. Periodic blind endometrial sampling or transvaginal ultrasound has been advocated by some. Because of the problems associated with either of these techniques alone, we recommended an approach that used transvaginal ultrasound and then proceeded to sonohysterography when the endometrial echo on transvaginal ultrasound was not reliably thin and distinct. The American College of Obstetricians and Gynecologists (ACOG), in its committee opinion, stated that patients receiving tamoxifen therapy should only have an annual pelvic exam with pap smear if they remain asymptomatic. Newer data suggest, however, that there are high- and low-risk groups that can be identified by pretreatment screening. Before tamoxifen therapy, 17% of patients have polyps. These patients have 17 times the incidence of atypical hyperplasia than those whose uterus was negative before tamoxifen therapy. Such findings call into question the validity of the only study of raloxifene where uterine safety was the primary endpoint. In that study, any woman with baseline endometrial findings other than pristinely negative (i.e., low risk) was excluded. However, other raloxifene studies without pretreatment screening show relative risk (RR) = 0.8 (95% CI = 0.2, 2.7) for endometrial carcinoma. This compares with the women over 50 years of age in the Breast Cancer Prevention Trial (National Surgical Adjuvant Breast and Bowel Project P-1) with tamoxifen when the RR = 4.01 (95% CI= 1.70, 10.90). The existence of potentially high- and low-risk groups should be taken into account in any future clinical trials looking at the endometrial safety of selective estrogen receptor modulators (SERMs).

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.

The effect of SERMs on the endometrium

Tamoxifen, the first clinically available SERM, was developed in 1966 and approved by the FDA (United States Food and Drug Administration) in 1978. It is the most prescribed antineoplastic drug in the world, with approximately 10 million women-use-years of experience. Tamoxifen has proved efficacious in all settings of breast cancer. However, in the mid-to-late 1980s, a series of letters to the editor and case reports announced an association between tamoxifen therapy in women with breast cancer and the development of endometrial carcinoma. Subsequently, in 1998, the observation of a significant 49% reduction in invasive breast cancer relative to placebo in a cohort of women at increased risk for the disease resulted in the early stopping of the National Surgical Adjuvant Breast and Bowel Project's (NSABP) P-1: Breast Cancer Prevention Trial (BCPT). Importantly, this was the first time that information became available about the effects of tamoxifen in healthy women, that is, women who did not already have breast cancer. In this healthy population, the relative risk of developing endometrial carcinoma in the tamoxifen arm was 2.54, although when stratified by age, in women over 50, the risk grew to 4.01. Thus, the risk appears to be confined to women over 50 because, in contrast, in women under 50 there was no statistically significant increase in the risk of endometrial carcinoma.

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

OBJECTIVE

To assess whether there is a decrease in endometrial thickness following discontinuation of tamoxifen treatment as measured by ultrasound.

DESIGN

Prospective study.

SETTING

Department of Obstetrics and Gynaecology, Sapir Medical Centre, Kfar-Saba, Israel.

POPULATION

Fifty-eight postmenopausal women with breast cancer who were treated with tamoxifen.

METHODS

Transvaginal ultrasonographic measurements of endometrial thickness.

MAIN OUTCOME MEASURES

Evaluation of the changes of endometrial thickness and the frequency the endometrium reached a thickness of < or = 5 mm at different time intervals after stopping tamoxifen treatment.

RESULTS

There was a significant decrease in median thickness of the endometrium, within six months after stopping tamoxifen, from 7.75 mm measured at the last ultrasonographic study performed before tamoxifen discontinuation down to 5.2 mm (P = 0.002). There were no further reductions in endometrial thickness, and it remained constantly low in subsequent ultrasonographic studies which were performed at various times up to 30 months following the discontinuation of tamoxifen treatment. While taking tamoxifen, only 25-9% of the women had an endometrial thickness of < or = 5 mm. This proportion doubled in their first six months after stopping.

CONCLUSIONS

Median thickness of endometrial thickness significantly reduced within six months following tamoxifen discontinuation, and remained constantly low thereafter. This finding may support use of ultrasonographic imaging for the measurement of tamoxifen's effect on the endometrium of postmenopausal breast cancer patients.

Errors in the measurement of endometrial depth using transvaginal sonography in postmenopausal women on tamoxifen: random error is reduced using saline instillation sonography

OBJECTIVE

The endometrium in women on tamoxifen is often made irregular by small cysts. The aim of this study was to assess the accuracy and precision of the measurement of endometrial depth by transvaginal sonography.

METHODS

The endometrial depth from endometrial biopsies obtained with the resectoscope in 15 women receiving tamoxifen was compared to the endometrial depth measured by TVS. The inter-observer variability was measured in 58 women.

RESULTS

In those biopsies of sufficient quality to allow a measurement, the corresponding depth measurement obtained by ultrasound was up to 3 mm greater than the histological measurement. The interobserver variability for the measurement of endometrial depth using TVS was assessed in 58 postmenopausal women on tamoxifen. The interobserver variability deteriorated as the mean endometrial depth increased, probably because the increase in depth resulted from greater morphological changes within the endometrium such as cyst formation which resulted in an irregular endometrial/myometrial boundary. This may, however, be improved by performing saline instillation sonography. In a prospective study of 10 postmenopausal women, the interobserver variability was significantly greater during tamoxifen treatment compared to pretreatment.

CONCLUSIONS

On the basis of the above, if uterine surveillance using TVS were to be offered to postmenopausal women on tamoxifen, then the procedure should be augmented by saline instillation sonography if the endometrial depth is > 4 mm, as this will improve the measurement precision and also identify intrauterine pathology.

Discrepancy between ultrasonography and hysteroscopy and histology of endometrium in postmenopausal breast cancer patients using tamoxifen

BACKGROUND

The increased risk of endometrial carcinoma following the use of tamoxifen has stimulated studies on endometrial diagnostic screening methods. In tamoxifen users the endometrial thickening observed with transvaginal ultrasonography (TVU) frequently cannot be confirmed by hysteroscopy or histology.

OBJECTIVE

The aim was to investigate the relationship between TVU and hysteroscopic and histologic endometrial findings in postmenopausal patients using tamoxifen.

METHODS

Fifty-three asymptomatic postmenopausal tamoxifen-using breast cancer patients underwent a gynecological examination combined with TVU. Patients with an endometrial thickness of >5 mm were offered hysteroscopy and endometrial biopsy.

FINDINGS

Thirty-one patients (58%) had an endometrial thickness of >5 mm with enhanced, inhomogeneous echogenicity. Hysteroscopy was performed in 22 patients and 3 underwent hysterectomy. Seven of 22 patients had endometrial polyps, histologically characterized by cystically dilated glands lined with atrophic epithelium and periglandular stromal condensation. Histology of the three hysterectomy specimens showed a similar picture of atrophic luminal epithelium, covering dilated glands lined with atrophic epithelium and surrounded by dense stroma, which resembled the histology of the endometrial polyps. In all three specimens the histologically measured endometrial thickness corresponded with that on TVU.

INTERPRETATION

Tamoxifen can induce specific endometrial changes consisting of cystically dilated glands with periglandular stromal condensation while the overlying epithelium remains atrophic. The changes occur either in the endometrium itself or as a protrusion of the endometrium, i.e., as endometrial polyps. These findings explain the discrepancy between ultrasound, hysteroscopy, and histology. Due to the high number of false-positive findings, TVU is not an effective screening instrument in these patients.

Uterine surveillance of asymptomatic postmenopausal women taking tamoxifen

The aim of this study was to assess the ability of transvaginal sonography (TVS) and office hysteroscopy with sharp curettage to characterize the morphological changes in the uteri of asymptomatic postmenopausal women taking long-term tamoxifen for breast cancer. The overall acceptability of a single-visit screening clinic for these women was also evaluated. Fifty-eight women were recruited from patients undergoing regular follow-up at the Leicester Royal Infirmary for breast cancer. A single-visit clinic was acceptable to 94.8% of these women. Transvaginal sonography detected endometrial thickness of greater than 5 mm in 84.5% of cases, but there was no relationship between total tamoxifen exposure and endometrial thickness. Transvaginal sonography also detected uterine lesions such as fibroids and endometrial cysts in 34.5% of cases. Hysteroscopy detected the latter uterine lesions in 53.4% of cases, with three cases (5.2%) of endometrial polyps also being identified in these women. Sharp curettage sampling of the endometrium produced specimens sufficient for diagnosis in 84.5% of cases; 70.7% of specimens were reported as showing types of 'quiescent' endometrium with 13.8% of specimens showing 'active' endometrium. In the latter group, there was a case of complex hyperplasia detected and also a case with granulomatous endometritis. For each histopathological diagnosis identified, there was a wide range of endometrial thickness recorded by TVS. A single-visit screening clinic involving TVS and hysteroscopy with sharp curettage was acceptable to asymptomatic women taking tamoxifen. However, hysteroscopy was more effective than TVS in detecting endometrial lesions such as polyps, fibroids and cystic areas. Although TVS detected endometrial thickness greater than 5 mm in the majority of cases, there were no malignancies detected and, for each histopathological classification, there was a wide range of endometrial thickness associated. Thus, the isolated use of TVS is insufficient for screening the endometria of these women.

The role of ultrasound in the detection of endometrial pathologies in asymptomatic postmenopausal breast cancer patients with tamoxifen treatment

Transvaginal ultrasonography is an effective diagnostic procedure, and thus, it can reasonably be used to determine which asymptomatic, postmenopausal breast cancer patient with tamoxifen treatment will require endometrial sampling. Overall, it seems that the contribution of pulsed Doppler flow in the diagnosis of endometrial pathologies in such patients is nonconclusive. It is suggested that sonohysterography is a useful diagnostic tool for the assessment of specific endometrial pathologies, especially of space-occupying lesions in the endometrial cavity, in such patients.

The effects of tamoxifen on the endometrium, blood flow of the uterine arteries and serum lipoprotein (a) levels in postmenopausal women

The purpose of this study was to evaluate the effect of tamoxifen therapy on the endometrium by transvaginal color Doppler sonography and on lipid profile focusing on lipoprotein (a) [Lp(a)] levels. Seventy-five postmenopausal breast cancer patients were examined by transvaginal color Doppler sonography and serum Lp(a) levels. Lipid parameters were measured after overnight fasting. Forty of the patients were treated with tamoxifen (20-30 mg/day) for at least 1 year. The remaining 35 patients did not receive tamoxifen and were used as controls. Statistical analysis was performed using t-test and Mann-Whitney U-test (Systat version 5.0). The patients receiving tamoxifen had significantly thicker endometrium (7.9 +/- 3.6 mm) compared to the control group (4.5 +/- 1.8 mm) (p < or = 0.001). The mean pulsatility index and resistance index of the uterine arteries in the tamoxifen group were 2.063 +/- 0.49 and 0.83 +/- 0.07, respectively, and were significantly lower than those of the control group (2.69 +/- 0.16 and 0.88 +/- 0.02) (p < 0.001). In addition, tamoxifen decreased total cholesterol (p < 0.001) and low-density lipoprotein cholesterol (p <0.001) and apolipoprotein B (p < 0.05) significantly. Tamoxifen also increased high density lipoprotein cholesterol (p < 0.05) and apolipoprotein A-I (p < 0.05). These results indicate that tamoxifen stimulates the endometrium and acts as an anti-atherogenic agent in postmenopausal women.

Tamoxifen and secondary tumours. An update

The nonsteroidal antiestrogen tamoxifen is the most widely used anticancer drug. In women with breast cancer, adjuvant therapy with tamoxifen reduces relapse and improves overall survival. In advanced breast cancer, the response rate is more than 50% in hormonal dependent disease. In women treated with adjuvant tamoxifen the incidence of new primary breast cancers is decreased. This latter observation has led to the initiation of prevention trials. In 1989 the first report from a large prospective randomised trial showed a significant increase of endometrial carcinoma among women treated with adjuvant tamoxifen. This effect may be linked to the somewhat paradoxical estrogenic properties of tamoxifen. The endometrial effects should be considered in the long term use of tamoxifen, and should also be taken into account in the evaluation of the prevention trials. Animal data indicate that tamoxifen can induce tumours in other organ systems, for example the liver, but no increase in primary liver cancer has been reported from the randomised trials. In some of these trials an increase in other gastrointestinal cancers (e.g. colon and gastric carcinoma) has been observed. The mechanism behind this may be different from that of the endometrium. In animal systems, tamoxifen has shown to induce DNA damage, with formation of DNA adducts. The risk of secondary gastrointestinal cancer needs to be further evaluated. The adverse effects of tamoxifen have led to the development of new anti-estrogenic drugs and other estrogen reducing agents (e.g. aromatase inhibitors).

Use of transvaginal sonography in the evaluation of endometrial hyperplasia and carcinoma

Published studies relating to the use of transvaginal sonography (TVS) in the evaluation of endometrial hyperplasia and carcinoma were reviewed. Approximately 80 percent of all curettage procedures performed for postmenopausal bleeding result in benign diagnoses, therefore, if a noninvasive modality such as TVS can be accurately used to determine endometrial thickness measurements below which pathology is less likely, sampling may be avoided. The largest study evaluating endometrial measurements in postmenopausal women with bleeding, known as the Nordic trial, found that for a cut-off value of < or = 4 mm, 96 percent sensitivity and 68 percent specificity was achieved. Another study evaluated endometrial echomorphology in addition to measurement and found that the combined approach improved the predictability of pathologic findings. TVS may also be used to assess the depth of myometrial invasion in patients already diagnosed histologically with endometrial carcinoma. Although MRI is considered the established tool in the presurgical evaluation of the patient with carcinoma, TVS was found to perform only slightly less accurately than MRI. The published studies regarding TVS and/or MRI are reviewed. Finally, the use of TVS in conjunction with a new modality, sonohysterography, in the evaluation of patients on tamoxifen therapy, is discussed. Although the published cut-off values for endometrial thickness measurements do not apply to this group of patients, a procedure whereby sterile saline is injected into the uterine cavity, via a thin catheter, provides additional information regarding endometrial contours. Once the procedure is performed, the supposed complex endometrial echo seen on TVS is often found to actually be located in the subendometrial myometrium and the endometrium itself is thin and regular. The role for TVS is well established in the search for endometrial hyperplasia and carcinoma, as well as evaluating the presence of myometrial invasion once the diagnosis is made.

Sonographic evaluation of the uterus in postmenopausal women receiving tamoxifen: characterization of mid-uterine abnormalities

BACKGROUND

Tamoxifen is known to exert agonist estrogenic effects on the uterus. Its use in postmenopausal women has also been associated with various endometrial and uterine abnormalities that can be detected by endovaginal sonography.

OBJECTIVE

To study postmenopausal patients receiving tamoxifen who were referred for evaluation following the detection of abnormal uterine findings by endovaginal sonography.

METHODS

Fifty-two women treated with tamoxifen for breast cancer who were found to have an abnormal uterine sonogram constituted the study population. Uterine sonograms were reviewed and clinical and sonographic data were correlated with the results of the histologic examinations.

RESULTS

Forty-five women demonstrated a thickened mid-uterine structure. Of these, in thirty-nine patients (87%) either no tissue of scant fragments of normal endometrium were obtained on curettage, and six women (13%) had endometrial hyperplasia. Seven women had fluid loculation lined by thin endometrium. Their subsequent histologic examination was normal. The sonograms of the women who demonstrated an appearance of a thickened endometrium but no neoplasia, characteristically demonstrated hyperechogenic cystic area with no midline echo.

CONCLUSIONS

Among 52 postmenopausal patients receiving tamoxifen presented with an abnormal uterine sonogram, 39 (75%) women were found to have a thick mid-uterine structure resembling a thickened endometrium without histologic evidence of neoplasia. This phenomenon can be characterized by typical sonographic features, and may be differentiated from other uterine abnormalities.

Ultrasonographic appearance of endometrium in postmenopausal breast cancer patients receiving tamoxifen

OBJECTIVES

To assess the ultrasonographic appearance and associated pathological changes of the endometrium in postmenopausal breast cancer patients with tamoxifen therapy.

STUDY DESIGN

Forty-eight postmenopausal breast cancer patients receiving 20 mg/day tamoxifen for 6-84 months (mean 29) and 38 control breast cancer patients without any hormonal treatment were examined by transvaginal ultrasonography and endometrial biopsy. Any thickening of the endometrium with cystic formations or homogeneous endometrial thickening > 10 mm detected by ultrasonography was defined as abnormal endometrial appearance. Homogeneous endometrial thickening < 10 mm without cystic formations was accepted as normal. Statistical analysis was performed using the Student's t-test and Mann-Whitney U test.

RESULTS

The two groups were similar in age and menopausal period. The patients on tamoxifen therapy had a thicker endometrium (8.6 +/- 6.6 mm) than the non-treated women (4.8 +/- 3.1 mm), which was found to be a statistically significant difference (P < 0.01). The sonographic evaluations showed abnormal endometrial appearance in 8 cases of tamoxifen treated women while the others revealed homogeneous thickness < 10 mm without cystic formations or a thin linear echo with or without fluid in the endometrial cavity. All 8 patients with cystic appearance had endometrial thickness > 10 mm. Only 1 patient had endometrial cancer on biopsy and no pathology was observed in the remaining 7 patients. In the control group, only 1 patient had abnormal ultrasonographic finding who had insufficient endometrial tissue on biopsy.

CONCLUSIONS

Tamoxifen can produce a sonographic image of the endometrium that resembles endometrial neoplasia. It is suggested that the discrepancy between the sonographic findings and histology may be the result of the stromal edema of the endometrium from tamoxifen treatment. Until more data are gathered, all postmenopausal breast cancer patients who are being treated with tamoxifen should have a periodic ultrasonographic examination and those presenting with a sonogram suggestive of endometrial pathology should undergo biopsy.

Transvaginal ultrasonography and endometrial changes in postmenopausal breast cancer patients receiving tamoxifen

OBJECTIVES

To assess an estrogenic effect of tamoxifen on the uterus and to evaluate the usefulness of transvaginal ultrasonography for identifying tamoxifen-induced endometrial pathology.

METHODS

One hundred and two postmenopausal breast cancer patients without gynecological symptoms were examined by transvaginal ultrasonography. Forty-eight patients were treated with tamoxifen and 54 patients served as reference. An endometrial thickness of > or = 6 mm (double-layer) was used as cut-off point for further hysteroscopic and histologic examination.

RESULTS

Thirty percent of the women taking tamoxifen had evidence of an abnormal postmenopausal endometrium compared with 6% in the reference group (P = 0.005). Those patients receiving tamoxifen had a significantly thicker endometrium (median 6.0 mm versus 2.0 mm; P < 0.001), a larger uterine volume (median 93 cm3 versus 72 cm3; P = 0.03) and more uterine fluid (12% versus 2%; P = 0.005). Furthermore, an ultrasonographic suspect 'Swiss-cheese' endometrial pattern was noted in almost a quarter of the patients treated with tamoxifen, but this was clearly not associated with intracavitary pathology.

CONCLUSIONS

Our data indicate that tamoxifen stimulates the uterine body and endometrium. The data also indicate that the ultrasonographic endometrial appearance during tamoxifen therapy may be misleading and that a high percentage (46%) of false-positive results occur. Therefore, in asymptomatic postmenopausal breast cancer patients taking tamoxifen, the findings on ultrasonography should be interpreted with caution.

Sonohysterography of the uterine cavity: preliminary investigations

OBJECTIVE

To compare sonohysterography (SH), in the exploration of the uterine cavity, with classical transvaginal sonography (TVS), hysterography (HSG), and hysteroscopy.

STUDY DESIGN

104 consecutive patients evaluated for uterine disorders underwent both TVS and SH. SH was obtained by distension of the uterine cavity with the instillation of an isotonic saline solution; 36 patients also underwent HSG; 82 women underwent surgery. Histologic findings were considered as gold standard. The criteria used to compare these methods were sensitivity, specificity, and negative and positive predictive values (NPV, PPV) for identifying pathology.

RESULTS

3 instillation failures occurred. SH was found to be more effective (sensitivity 94%, specificity 98%) than HSG (sensitivity 67%, specificity 94%). The difference between TVS and SH was less marked, SH showing some superiority (sensitivity 88%, specificity 98%) to TVS (sensitivity 77%, specificity 93%).

CONCLUSION

SH represents an improvement over conventional TVS and is fully capable of replacing HSG for the study of the uterine cavity.

The endocrine prevention of breast cancer

A clear explanation for the high incidence of breast cancer in modern women is now possible. The risk of breast cancer rises steeply from menarche until menopause. Associated with the reproductive process, the ovary, including the corpus luteum, produces substantial amounts of estrogen and progesterone, both of which induce growth of the breast epithelium. This sex-steroid-driven breast epithelial cell proliferation increases the risk of carcinogenesis by accelerating the occurrence of somatic genetic errors. Postmenopausally, as there is little cell proliferation, the breast epithelium is more "resistant" to mutagenic effects, and breast cancer risk rises at a low rate. Unfortunately, the genetic errors accumulated during the premenopausal period are not lost following menopause, and breast cancer risk remains high. Sex-steroid antagonists, such as tamoxifen, may reduce breast cancer incidence both by blocking breast epithelial cell proliferation and by direct antitumor effects on clinically occult breast cancers. The rationale for a contraceptive designed to reduce breast cell proliferation by decreasing premenopausal sex-steroid exposure is presented.