Late cervical and vaginal clear cell adenocarcinoma in women exposed in utero to diethylstilbestrol: Evaluation and screening

OBJECTIVES

We aimed to evaluate the risk of cervical and vaginal clear cell adenocarcinoma (CCA) in women, aged 50 years or more, exposed in utero to diethylstilbestrol (DES) and contribute to a reevaluation of the recommendations for cervical and vaginal cancer and pre-cancer screening for these women.

METHODS

We carried out a retrospective review for patients received in a cancer institute. Two cohorts were consecutively studied, the first from 1970 to 2003 and the second from 2004 to 2021, and then linked.

RESULTS

During the first period, we observed 61 CCA cases, with a mean age at diagnosis of 23 years (7-42), 36 (59%) following DES exposure in utero. During the second period, we found 27 cases, with one case of DES exposure (4%) for a women diagnosed at the age of 40 years. The mean age of the second cohort was 38 years (14-79). For the seven women aged 50 years or more at the time of CCA diagnosis, DES exposure was excluded for five and considered unlikely for the other two.

CONCLUSION

In total, 88 cases of cervical or vaginal CCA were observed over a period of 51 years in a cancer center. The 37 cases associated with DES exposure represented approximatively one third of the CCA related to DES expected in France. DES exposure was improbable for the seven cases of CCA for women aged 50 years or more. These results do not support the hypothesis of late cervical or vaginal CCA in women exposed to DES in utero and indicate the need for larger multicentric studies. For the present, we propose specific screening for women exposed to DES in utero in terms of : 1) methods: association of cytology and hrHPV testing, with cervical and vaginal sampling, 2) timing : annual, or without exceeding a three-year interval, continuing after 65 years of age and after hysterectomy.

Prenatal diethylstilbestrol exposure and cancer risk in women

In the Diethylstilbestrol [DES] Combined Cohort Follow-up, the age- and calendar-year specific standardized incidence ratio [SIR] for clear cell adenocarcinoma [CCA] was 27.6 (95% confidence interval [CI] 7.51-70.6) for the exposed women. The SIR for breast cancer was 1.17 (95% CI 1.01-1.36) and the hazard ratio [HR] adjusted for birth year and cohort for comparison with the unexposed was 1.05 (95% CI 0.79-1.41). The SIR for pancreatic cancer was 2.43 (95% CI 1.21-4.34) and the adjusted HR for comparison with unexposed women was 7.16 (95% CI 0.84-61.5). There was little evidence of excess risk for other sites. There appeared to be a deficit in risk for endometrial cancer among the exposed (SIR 0.61; 95% CI 0.35-0.98), and an excess in the unexposed (SIR 1.55; 95% CI 0.95-2.40); the adjusted HR was 0.45 (95% CI 0.22-0.93) for the internal comparison. There was no overall excess cancer risk in exposed women compared with general population rates (1.06; 95% CI 0.95-1.17) or with unexposed participants (adjusted HR 1.03; 95% CI 0.84-1.25). These data do not support the suggestion that there is a diathesis of cancers in DES exposed female offspring The excess risk of breast and pancreatic cancers that we observed is concerning and warrants continued follow-up and mechanistic investigation. Environ. Mol. Mutagen. 60:395-403, 2019. Published 2017. This article is a US Government work and is in the public domain in the USA.

DES daughters in France: experts' points of view on the various genital, uterine and obstetric pathologies, and in utero DES exposure

BACKGROUND

Compensation of diethylstilbestrol exposure depends on the judicial system. In France, girls having been exposed to diethylstilbestrol are currently being compensated, and each exposure victim is being evaluated. Fifty-nine expert evaluations were studied to determine the causal relation between exposure to diethylstilbestrol and the pathologies attributable to diethylstilbestrol.

METHODS

The following were taken into consideration: age at the first signs of the pathology; age of the sufferer at the time of evaluation; the pathologies grouped into five categories: fertility disorders - cancers - mishaps during pregnancy - psychosomatic complaints - pathologies of "3rd generation DES victims"; submission of proof of DES exposure; the degree of causality determined (direct, indirect, ruled out).

RESULTS

61% of the cases related to fertility disorders, 28.8% to cancer pathologies (clear-cell adenocarcinoma), 18.6% to mishaps during pregnancy, 8.5% to disorders resulting from preterm delivery, and 3.4% to psychosomatic disorders. Some cases involved a combination of two types of complaints. Indirect causality was determined in 47.1% of the cases involving primary sterility, in 66.7% involving secondary sterility, and in 5 out of 6 cases of total sterility. There is direct causality between in utero diethylstilbestrol exposure and vaginal or cervical clear cell adenocarcinoma. Causality is indirect in the case of disorders linked to prematurity in third generation victims.

CONCLUSION

Causality was determined by the experts on the basis of scientific criteria which attribute the presenting pathologies to diethylstilbestrol exposure. When other risk factors come into play, or when exposure is indirect (third generation), this causality is diminished.

The development of cervical and vaginal adenosis as a result of diethylstilbestrol exposure in utero

Exposure to exogenous hormones during development can result in permanent health problems. In utero exposure to diethylstilbestrol (DES) is probably the most well documented case in human history. DES, an orally active synthetic estrogen, was believed to prevent adverse pregnancy outcome and thus was routinely given to selected pregnant women from the 1940s to the 1960s. It has been estimated that 5 million pregnant women worldwide were prescribed DES during this period. In the early 1970s, vaginal clear cell adenocarcinomas (CCACs) were diagnosed in daughters whose mother took DES during pregnancy (known as DES daughters). Follow-up studies demonstrated that exposure to DES in utero causes a spectrum of congenital anomalies in female reproductive tracts and CCACs. Among those, cervical and vaginal adenoses are most commonly found, which are believed to be the precursors of CCACs. Transformation related protein 63 (TRP63/p63) marks the cell fate decision of Müllerian duct epithelium (MDE) to become squamous epithelium in the cervix and vagina. DES disrupts the TRP63 expression in mice and induces adenosis lesions in the cervix and vagina. This review describes mouse models that can be used to study the development of DES-induced anomalies, focusing on cervical and vaginal adenoses, and discusses their molecular pathogenesis.

Adverse health outcomes in women exposed in utero to diethylstilbestrol

BACKGROUND

Before 1971, several million women were exposed in utero to diethylstilbestrol (DES) given to their mothers to prevent pregnancy complications. Several adverse outcomes have been linked to such exposure, but their cumulative effects are not well understood.

METHODS

We combined data from three studies initiated in the 1970s with continued long-term follow-up of 4653 women exposed in utero to DES and 1927 unexposed controls. We assessed the risks of 12 adverse outcomes linked to DES exposure, including cumulative risks to 45 years of age for reproductive outcomes and to 55 years of age for other outcomes, and their relationships to the baseline presence or absence of vaginal epithelial changes, which are correlated with a higher dose of, and earlier exposure to, DES in utero.

RESULTS

Cumulative risks in women exposed to DES, as compared with those not exposed, were as follows: for infertility, 33.3% vs. 15.5% (hazard ratio, 2.37; 95% confidence interval [CI], 2.05 to 2.75); spontaneous abortion, 50.3% vs. 38.6% (hazard ratio, 1.64; 95% CI, 1.42 to 1.88); preterm delivery, 53.3% vs. 17.8% (hazard ratio, 4.68; 95% CI, 3.74 to 5.86); loss of second-trimester pregnancy, 16.4% vs. 1.7% (hazard ratio, 3.77; 95% CI, 2.56 to 5.54); ectopic pregnancy, 14.6% vs. 2.9% (hazard ratio, 3.72; 95% CI, 2.58 to 5.38); preeclampsia, 26.4% vs. 13.7% (hazard ratio 1.42; 95% CI, 1.07 to 1.89); stillbirth, 8.9% vs. 2.6% (hazard ratio, 2.45; 95% CI, 1.33 to 4.54); early menopause, 5.1% vs. 1.7% (hazard ratio, 2.35; 95% CI, 1.67 to 3.31); grade 2 or higher cervical intraepithelial neoplasia, 6.9% vs. 3.4% (hazard ratio, 2.28; 95% CI, 1.59 to 3.27); and breast cancer at 40 years of age or older, 3.9% vs. 2.2% (hazard ratio, 1.82; 95% CI, 1.04 to 3.18). For most outcomes, the risks among exposed women were higher for those with vaginal epithelial changes than for those without such changes.

CONCLUSIONS

In utero exposure of women to DES is associated with a high lifetime risk of a broad spectrum of adverse health outcomes. (Funded by the National Cancer Institute.).

Clear cell adenocarcinoma of the ovary associated with in utero diethylstilbestrol exposure: case report and clinical overview

BACKGROUND

Clear cell adenocarcinoma of the vagina and cervix were previously shown to be tumors occurring in female offspring exposed prenatally to diethylstilbestrol. This report describes the first clinical case of clear cell adenocarcinoma of the ovary linked to early diethylstilbestrol exposure in utero.

CASE

A 45-year-old woman presented with a self-discovered lump in the lower abdominal quadrant. She underwent surgery and staging that revealed clear cell adenocarcinoma confined to the left ovary. Foci of high-grade squamous neoplastic proliferation, inflammation, and a paratubal cyst were also present on the pathology specimen. Medical records established unequivocally that the patient's mother received diethylstilbestrol therapy throughout the pregnancy.

CONCLUSION

Our case is consistent with clear cell adenocarcinoma, probably related to diethylstilbestrol exposure in utero. It reinforces the need for continued vigilance in individuals prenatally exposed to this drug.

[Vaginal and cervical cancer due to diethylstilbestrol (DES); end epidemic]

OBJECTIVE

To determine the current situation regarding the epidemic of clear cell adenocarcinoma of the vagina and the uterine cervix (CCAC) in relation to the exposure in utero to diethylstilbestrol (DES).

DESIGN

Descriptive.

METHODS

Patients with CCAC of the uterine cervix or vagina born after 1946 and diagnosed in the period 1969-2005, were identified through the Nationwide network and registry of histo- and cytopathology in the Netherlands and from 2003 onwards through the Netherlands Cancer Registry. Exposure data and clinical data were obtained by means of questionnaires and medical records. The histology slides of tumours were reviewed. For the patients who did not provide consent, only the date of diagnosis and age at diagnosis were known (n = 10).

RESULTS

Up to 2005, 144 CCAC patients were registered. Age at diagnosis varied from 8-54 years (mean: 28 years). In the years 1981-2000, the number of new diagnoses in 4 successive 5-year periods was fairly stable (n=26-30) but it was considerably lower in 2001-2005 (n=13). Of the patients whose history of intrauterine exposure to DES was known, 62% had been exposed (76/122). The mean age at diagnosis was 24 years for exposed patients compared to 32 years for non-exposed patients. The 10-year survival rate was 78% (95% CI: 68-87) for exposed and 69% (95% CI: 56-82) for non-exposed patients.

CONCLUSION

Since 2000, the incidence of CCAC of the vagina and cervix has decreased markedly compared to the situation in the 1980s and 1990 s. In particular, the number of patients with CCAC exposed in utero to DES has decreased. Whether this decrease shall continue over the coming years remains to be seen.

Diethylstilbestrol (DES)-induced clear cell adenocarcinoma of the vagina metastasizing to the brain

BACKGROUND

Primary vaginal clear cell adenocarcinoma (CCA) is a rare gynecological malignancy occurring predominantly in young females with a history of diethylstilbestrol exposure in utero. Vaginal CCA commonly metastasizes to the lungs and the supraclavicular lymph nodes; however we present a rare case of diethylstilbestrol-induced vaginal CCA with cerebral metastases.

CASE DESCRIPTION

A 43-year-old woman with prenatal diethylstilbestrol exposure and history of vaginal CCA treatment 8 years prior to current presentation noted new onset headache and dizziness. MRI showed an enhancing mass in the right frontal lobe. Histopathology was consistent with CCA.

CONCLUSIONS

This case report highlights the necessity of close extended follow-up in patients with a history of vaginal CCA and demonstrates the potential for spread of primary vaginal CCA to the brain.

Detection of chromosomal aberrations by fluorescence in situ hybridization in cervicovaginal biopsies from women exposed to diethylstilbestrol in utero

Epidemiologic studies have associated estrogens with human neoplasms such as those in the endometrium, cervix, vagina, breast, and liver. Perinatal exposure to natural (17beta-estradiol [17beta-E(2)]) and synthetic (diethylstilbestrol [DES]) estrogens induces neoplastic changes in humans and rodents. Previous studies demonstrated that neonatal 17beta-E(2) treatment of mice results in increased nuclear DNA content of cervicovaginal epithelium that precedes histologically evident neoplasia. In order to determine whether this effect was associated with chromosomal changes in humans, the frequencies of trisomy of chromosomes 1, 7, 11, and 17 were evaluated by the fluorescence in situ hybridization (FISH) technique in cervicovaginal tissue from 19 DES-exposed and 19 control women. The trisomic frequencies were significantly elevated in 4 of the 19 (21%) DES-exposed patients. One patient presented with trisomy of chromosomes 1, 7, and 11, while trisomy of chromosome 7 was observed in one patient. There were two patients with trisomy of chromosome 1. Trisomy of chromosomes 1, 7, 11, and 17 was not observed in the cervicovaginal tissue taken from control patients. These data suggest that DES-induced chromosomal trisomy may be an early event in the development of cervicovaginal neoplasia in humans.

[Vagina cancer in a young woman exposed to diethylstilbestrol: case report and literature review]

We analyzed a 20 year-old patient case exposed in utero to diethylstilbestrol, as probably predisposed factor in vaginal cancer. The histopathological report of the incisional biopsy was clear cell vaginal adenocarcinoma, stage III, widespread to the pelvic wall, with metastasis to regional lymph nodes, and lack of distant metastasis. We decided surgical management: protocolized laparotomy, peritoneal washing, retroperitoneal node biopsies and a radical hysterectomy, Piver III, with two thirds parts of vagina. By poor prognosis we decided to offer an adjuvant management, with systemic chemotherapy.

The health effects of diethylstilbestrol revisited

Although diethylstilbestrol has not been prescribed commonly for more than 25 years, its effects on the health of exposed persons are still important. In this article, we summarize current information about the major health effects of diethylstilbestrol exposure and delineate implications for nurses. Nurses can help to identify persons at risk from prior diethylstilbestrol exposure, facilitate comprehensive assessments of persons exposed to diethylstilbestrol, and share current information about diethylstilbestrol.

Six Cases of Women with Diethylstilbestrol in Utero Demonstrating Long-Term Manifestations and Current Evaluation Guidelines

Diethylstilbestrol (DES), a nonsteroidal estrogen, was widely used in the United States from 1940 through 1971 to prevent pregnancy loss. In the late 1960s, an association was made with an increased incidence of clear cell adenocarcinoma in young women exposed in utero to DES. Additional study of these women over the next 35 years has shown an increased risk of other health problems including intraepithelial neoplasia, ectopic pregnancy, first trimester spontaneous abortion and second trimester pregnancy loss. The National Institutes of Health continues to fund studies to follow cohorts of DES-exposed mothers, daughters, sons and third generation children. The Centers for Disease Control have conducted a large DES Education Project and have established guidelines for management. The following six cases studies illustrate common problems seen in DES exposed daughters and management of problems encountered.

Perineal talc exposure and epithelial ovarian cancer risk in the Central Valley of California

Perineal talc use has been suggested as a possible risk factor for ovarian cancer based on its structural similarity to asbestos, a known human carcinogen. A population-based epidemiologic case-control study of epithelial ovarian cancer (EOC) was conducted in 22 counties of Central California that comprise the reporting area for 2 regional cancer registries. Telephone interviews were conducted with 256 cases diagnosed in the years 2000-2001 and 1,122 controls frequency-matched on age and ethnicity. The interview obtained information on demographic factors, menstrual and reproductive experience, exogenous hormone use, surgical history and family history of cancer. Questions on perineal talc use included frequency of use, duration of use and specific years when talc was used. Multivariate-adjusted odds ratio (OR) and 95% confidence intervals (CI) were derived from unconditional logistic regression. The OR for ever use of talc was 1.37 (CI = 1.02-1.85) compared to never users. However, no dose response association was found. Tubal ligation (TL) modified the effect of talc on EOC such that women with TL had an OR of 0.88 (CI = 0.46-1.68) associated with perineal talc use, whereas women with no TL had an OR of 1.54 (CI = 1.10-2.16). Talc use and EOC risk was highest in women with serous invasive tumors (OR = 1.77; CI = 1.12-2.81). This study provides some support for the hypothesis that perineal talc use is associated with an increased risk of EOC.

Endobronchial clear cell adenocarcinoma occurring in a patient 15 years after treatment for DES-associated vaginal clear cell adenocarcinoma

BACKGROUND

Clear cell adenocarcinoma (CCA) of the vagina and cervix in young women is associated with prenatal exposure to diethylstilbestrol (DES). Parenchymal pulmonary metastases are known to occur following treatment of the primary tumor. Most recurrences present within 2 to 3 years of the initial diagnosis.

CASE

This is a case report of a solitary endobronchial clear cell adenocarcinoma occurring 15.3 years after the initial diagnosis of DES-induced CCA.

CONCLUSIONS

This case suggests that management of clear cell cancer survivors should involve long-term follow-up because of the potential for the appearance of a new focus of clear cell adenocarcinoma.

Clinical implications of DES

Once prescribed to pregnant women to prevent risk of spontaneous abortion, diethylstilbestrol (DES) is now associated with an increased risk of breast cancer, clear cell adenocarcinoma (CCA) of the vagina and cervix, and reproductive anomalies. This article will summarize the potential long-term health implications of DES, the role of nurse practitioners in identifying exposed individuals, and proper clinical management.

Diethylstilbestrol (DES) update: recommendations for the identification and management of DES-exposed individuals

Diethylstilbestrol (DES) was etiologically linked to clear cell adenocarcinoma of the vagina in 1971. This article reviews on-going research and emerging information relevant to DES-related health risks, thereby enabling women's health care providers to maintain an evidence-based practice for their DES-exposed patients. To accomplish these goals, the Center for Disease Control and Prevention (CDC) has initiated a national education campaign. This article describes the reasons for this new initiative, the target audiences, the DES historical framework (including major studies and findings), and populations that are affected. Clinical steps for the identification and management of the DES-exposed individual and resultant implications for midwifery and women's health practices are reviewed.

Mutations in the VHL gene from potassium bromate-induced rat clear cell renal tumors

Potassium bromate (KBrO(3)) is a rat renal carcinogen and a major drinking water disinfection by-product in water disinfected with ozone. Clear cell renal tumors, the most common form of human renal epithelial neoplasm, are rare in animals but are inducible by KBrO(3) in F344 rats. Detection of cytoplasmic periodic acid-Schiff-positive granules in clear cell tumors, indicative of glycogen accumulation, provides evidence of their biochemical similarity to human counterparts. Mutation in the coding region of the von Hippel-Lindau (VHL) gene is frequently detected in human clear cell renal carcinomas. Detection of VHL mutations in KBrO(3)-induced rat renal tumors could enhance the relevancy of these rat renal tumors for human health risk assessment. Formalin-fixed paraffin-embedded control tissues and renal tumors from male F344 rats exposed to KBrO(3) in the drinking water for 2 years were examined microscopically and were microdissected for DNA extraction. The coding sequence and a promoter region of the VHL gene were examined by polymerase chain reaction-single strand conformation polymorphism and/or DNA sequencing. Two of nine clear cell renal tumors carried the same C to T mutation at the core region of the Sp1 transcription factor binding motif in the VHL promoter and one of four untreated animals had C to T mutation outside the highly conserved core region. Mutation in the VHL coding sequence was only detected in one tumor. No VHL mutations were observed in three chromophilic tumors. KBrO(3)-induced rat renal tumors are morphologically similar to their human counterpart but the genetic basis of tumorigenesis is different.

Findings in female offspring of women exposed in utero to diethylstilbestrol

OBJECTIVE

To examine a group of women (third-generation daughters) whose mothers were exposed in utero to diethylstilbestrol (DES) and compare their findings on pelvic examination with those noted in their mothers.

METHODS

Letters were mailed to women documented to have been exposed in utero to DES who had given birth to a female offspring, inviting them to have their daughters come in for a detailed history and pelvic examination. Records of the mothers whose daughters appeared for examination were reviewed, and findings noted at the time of their initial examination were recorded. Detailed pelvic examination of the third-generation daughters included colposcopic examination and iodine staining of the vagina and cervix and Papanicolaou smear. The findings observed in these women were compared with those noted in their mothers at the time of their mothers' first examination.

RESULTS

Twenty-eight third-generation daughters were examined. Three of the daughters were delivered from one mother. Review of the mothers' records indicated that 16 (61.5%) of the mothers exposed to DES during their pregnancy demonstrated structural changes of the cervix, upper vagina, or vaginal epithelial changes consisting of adenosis, nonstaining vaginal epithelium after application of iodine solution, or white epithelium within the vagina. None of the daughters were found to have changes usually associated with DES exposure.

CONCLUSION

The absence of abnormalities in the lower genital tract in third-generation women compared with the high frequency of these abnormalities in their mothers suggests that third-generation carryover effects of in utero DES exposure are unlikely.

Order-restricted dose-related trend tests

Methods of isotonic regression are proposed to increase the power of common trend tests in situations where a monotonicity constraint is imposed upon the dose-response function. Isotonic versions of Cochran-Armitage type trend tests for binary response data are developed, and the bootstrap method is used in finding the empirical distributions of the test statistics and their critical values. The isotonic likelihood ratio test with a survival adjustment is also proposed. This survival adjustment can be applied to the likelihood ratio test for either the order-restricted or unrestricted parameter cases. To achieve the isotonic modifications, an amalgamation algorithm is applied when the observed dose-response is non-monotonic. A Monte Carlo simulation study comparing these trend tests shows the advantages of the isotonic modifications and survival adjustment. By applying the proposed methods to data from a toxicology and carcinogenesis study conducted as part of the National Toxicology Program, the effect of CI Pigment Red 23 is investigated.

Concurrent primaries of vaginal clear cell adenocarcinoma and endometrial adenocarcinoma in a 39-year old woman with in utero diethylstilbestrol exposure

Diethylstilbestrol (DES) was used widely in the late 1940s in an attempt to prevent adverse pregnancy outcomes. In 1971 the US Food and Drug Administration proscribed its use for pregnancy support secondary to its association with clear cell adenocarcinoma of the vagina. Several studies in animal models demonstrated an association with endometrial cancer among offspring following in utero DES exposure. To date, there is only one case report of endometrial cancer in women exposed to DES in utero. We present the first case, to our knowledge, of a woman exposed to DES in utero who presented with double primaries of clear cell cancer of the vagina concomitant with endometrial cancer.

[Synthetic estrogen as a endocrine disruptor--diethylstilbestrol and oral contraceptives]

Recently, considerable attention has been focused on certain environmental contaminants, endocrine disruptors, of industrial origin that may mimic the action of estrogen. Oral contraceptives containing ethynylestradiol, a synthetic estrogen, have been suspected to have adverse environmental effects since prenatal exposure to diethylstilbestrol, another synthetic estrogen, was reported to be associated with clear cell adenocarcinoma of the vagina in female offspring. In terms of magnitude and extent, such exposures to synthetic estrogens are now considered virtually insignificant compared with the secretion and excretion of natural estrogens from humans. However, as is the case with all other chemicals, continuous and rational risk assessment and risk management of these synthetic estrogens must be made.

Intrauterine exposure to diethylstilbestrol: long-term effects in humans

DES is the most carefully scrutinized EDC and its history provides valuable insights into the current evaluation of less well-studied EDCs. This review summarizes the health effects of prenatal exposure to diethylstilbestrol (DES) and emphasizes the role of DES as the first endocrine disrupting chemical (EDC). Vaginal clear cell adenocarcinoma (CCAC), the most severe consequence of prenatal exposure to DES, affected only 0.1% of exposed females, while the far more prevalent teratogenic and reproductive effects of DES were only discovered when DES daughter were screened for CCAC. Initial studies, conducted before most DES daughters had tried to conceive, examined vaginal cancer and vaginal, cervical and uterine abnormalities. Subsequently, several controlled studies demonstrated the increased risk of adverse reproductive outcomes in DES daughters. While most DES daughters can eventually experience a live birth, this is less likely in women with genital tract abnormalities, in whom there is a two-thirds chance that each pregnancy will be unsuccessful. In DES sons, who have been far less studied, results suggest male reproductive toxicity, but are less consistent. The importance of dose and gestational age at initial exposure are discussed, and the implications of DES findings for the evaluation of risks from current EDCs emphasized.

Modifying effects of ethinylestradiol but not methoxychlor on N-ethyl-N-nitrosourea-induced uterine carcinogenesis in heterozygous p53-deficient CBA mice

It is unknown whether endocrine-disrupting chemicals (EDCs) with estrogenic activities have any modifying effects on uterine carcinogenesis. In our previous study, we established a uterine-carcinogenesis model that is useful for detecting tumor-modifying effects of EDCs by the administration of N-ethyl-N-nitrosourea (ENU) to female heterozygous p53-deficient CBA mice [p53 (+/-) mice]. To investigate the effects of ethinylestradiol (EE) and methoxychlor (MXC) on development of ENU-induced uterine tumors, female p53 (+/-) mice and their wild-type littermates [p53 (+/+) mice] received an intraperitoneal injection of 120 mg/kg body weight (bw) of ENU, followed, in Group 1, by no further treatment; in Group 2, by a diet containing 1 ppm EE; in Group 3, by a diet containing 5 ppm EE for 4 weeks and 2.5 ppm EE thereafter; and in Group 4, by a diet containing 2000 ppm MXC for 26 weeks. Uterine proliferative lesions that were induced were composed of both endometrial-stromal and epithelial-cell types. Endometrial stromal sarcomas were induced in p53 (+/-) mice of Groups 1 to 4, and the incidence (87%) in Group 3 was significantly increased compared to Group 1 (47%). Atypical hyperplasias (clear-cell type) of the endometrial gland in p53 (+/-) mice were seen at incidences of 0, 14, 60, and 0% in Groups 1, 2, 3, and 4, respectively, while their incidence in p53 (+/+) mice was 0, 7, 53, and 0%, respectively, with a significant difference between Groups 1 and 3 in both cases. One p53 (+/-) mouse in Group 3 also had an adenocarcinoma consisting of clear cells, and the PCNA labeling indices of the clear-cell atypical hyperplasias, and this endometrial adenocarcinoma, were higher than those of glandular hyperplasias. The present study suggests that 2.5 ppm EE, but not MXC, exerts tumor-promoting effects on stromal and epithelial proliferative lesions of the uteri in p53 (+/-) mice initiated with ENU.

Hyperestrogenism: a relevant risk factor for the development of cancer from endometriosis

OBJECTIVE

Endometriosis is extremely common in developed countries. Obesity is a major health concern and may cause hyperestrogenism. Hormonal replacement, particularly unopposed estrogens after hysterectomy, is becoming popular. Because endometriosis is ectopic endometrium, hyperestrogenism (either endogenous or exogenous) may cause hyperplasia or transformation into cancer. This study was conducted to describe the main clinical and pathologic features of malignancies in endometriosis and define the treatment and outcome and to compare patients who had cancer arising in endometriosis with patients who had endometriosis but no cancer.

METHODS

Patients who had tumors from endometriosis diagnosed from 1986 to 1997 were analyzed retrospectively. Each patient was matched with two control patients (endometriosis without cancer) treated during the same study interval. Clinical and epidemiologic variables were compared to identify risk factors for the development of cancer.

RESULT

We identified 31 patients with cancer developing from endometriosis. Fifteen women were obese, 9 had a history of endometriosis, and 9 were taking unopposed estrogen. Endometrioid adenocarcinoma was the most common histologic type (16 patients). When the patients with cancer were compared with controls, no significantly higher risk for the development of cancer was found with prolonged use of unopposed estrogens or with higher body mass index, but a trend was observed. When obesity and use of unopposed estrogens were considered together, the difference was statistically significant (P = 0.05).

CONCLUSION

Hyperestrogenism, either endogenous or exogenous, is a significant risk factor for the development of cancer from endometriosis. The prevalences of endometriosis, obesity, and use of hormonal replacement therapy in women in developed countries are increasing, and this trend justifies the assumption that cancer developing in endometriosis might become more common in the future.

The endometrium in breast cancer patients on tamoxifen

We restudied histologically and immunohistochemically 17 endometrial carcinomas, 2 malignant mixed tumors and 180 endometria with benign changes during or after tamoxifen therapy. The carcinomas were subtyped according to the 1994 WHO-classification. Endometrial biopsies were taken only if the endometrial thickness was > 8 mm sonographically, when a polyp was seen, or for postmenopausal bleeding. About half of the endometrial specimens showed simple or cystic atrophy, 55-76% had cystic-atrophic polyps or regressive hyperplasia. Depending upon the dose of tamoxifen, 7-19% (30 mg) to 27-36% (20 mg) showed moderate glandular proliferation. 20-33% had foci of mucinous, clear cell or serous-papillary metaplasia. 68-70% revealed diffuse extensive fibrosis of the endometrial stroma. None of 11 patients biopsied before starting tamoxifen therapy had advanced endometrial glandular proliferation in the second endometrial biopsy after tamoxifen treatment. None of the 19 endometrial neoplasms after tamoxifen therapy was of the endometrioid type: 11 were mucinous adenocarcinomas, 4 clear cell carcinomas, 2 serous-papillary carcinomas, one carcinosarcoma and one malignant Mullerian mixed tumor. The reasons for discrepancies between suspicious sonograms and endometrial atrophy are discussed.

Hormone replacement therapy and risk of epithelial ovarian cancer

It has been suggested that oestrogen replacement therapy is associated with risk of epithelial ovarian cancer of the endometrioid type. Using data from an Australian population-based case-control study, the relation between unopposed oestrogen replacement therapy and epithelial ovarian cancer, both overall and according to histological type, was examined. A total of 793 eligible incident cases of epithelial ovarian cancer diagnosed from 1990 to 1993 among women living in Queensland, New South Wales and Victoria were identified. These were compared with 855 eligible female controls selected at random from the electoral roll, stratified by age and geographic region. Trained interviewers administered standard questionnaires to obtain detailed reproductive and contraceptive histories, as well as details about hormone replacement therapy and pelvic operations. No clear associations were observed between use of hormone replacement therapy overall and risk of ovarian cancer. Unopposed oestrogen replacement therapy was, however, associated with a significant increase in risk of endometrioid or clear cell epithelial ovarian tumours (odds ratio (OR) 2.56; 95% confidence interval (CI) 1.32-4.94). In addition, the risk associated with oestrogen replacement therapy was much larger in women with an intact genital tract (OR 3.00; 95% CI 1.54-5.85) than in those with a history of either hysterectomy or tubal ligation. Post-menopausal oestrogen replacement therapy may, therefore, be a risk factor associated with endometrioid and clear cell tumours in particular. Additionally, the risk may be increased predominantly in women with an intact genital tract. These associations could reflect a possible role of endometriosis in the development of endometrioid or clear cell ovarian tumours.

von Hippel-Lindau gene mutations in N-nitrosodimethylamine-induced rat renal epithelial tumors

BACKGROUND

Mutations in the von Hippel-Lindau (VHL) gene are common in human clear cell kidney cancers. Carcinogens in cigarette smoke, especially nitrosamines, are known to induce kidney tumors of a variety of histologic types in rodents--but with no evidence of VHL mutations; however, none of these tumors resembled human clear cell carcinomas. We examined N-nitrosodimethylamine-induced kidney tumors of the clear or mixed clear/granular cell type in Wistar rats to assess the presence of VHL mutations.

METHODS

Sections of eight clear or mixed clear/granular cell kidney tumors that had been formalin fixed and paraffin embedded were microdissected. DNA was extracted from the microdissected tissue, and exons 1-3 of the rat VHL gene were examined by use of polymerase chain reaction and cycle sequencing techniques.

RESULTS

Four VHL gene mutations (three G:C to A:T and one A:T to G:C) were detected in three of the tumors in contrast to no mutations in 40 previously reported rat kidney tumors of other histologic types (three of eight tumors versus none of 40; two-sided Fisher's exact test; P=.003). Only tumors showing prominent swollen clear cell cytology with a signet-ring appearance had VHL mutations.

CONCLUSIONS

To our knowledge, this is the first report of VHL mutations in kidney tumors after direct chemical exposure and provides a possible molecular pathway linking tobacco smoking to kidney cancer.

Bcl-2 protein expression associated with resistance to apoptosis in clear cell adenocarcinomas of the vagina and cervix expressing wild-type p53

BACKGROUND

Clear cell adenocarcinomas (CCAs) of the vagina and cervix are rare tumors that often overexpress wild-type p53. In vitro, expression of protooncogene bcl-2 can block p53-mediated apoptosis. The objective of this study was to determine if bcl-2 is expressed in CCAs and whether this expression is associated with inhibition of apoptosis.

METHODS

Twenty-one paraffin-embedded clear cell adenocarcinomas were immunohistochemically stained for bcl-2 (antibody M 887, Dako, Carpinteria, CA) and DNA fragmentation (ApopTag, Oncor, Gaithersburg, MD), a marker for apoptosis. Fifteen tumors were associated with in utero exposure to diethylstilbestrol (DES). Prior p53 gene analysis had indicated the presence of wild-type p53 in each tumor. Human lymphoid tissue containing bcl-2-expressing lymphocytes and DNase I-exposed CCA tissue sections were used as positive controls for the bcl-2 and apoptosis assays, respectively. Expression of bcl-2 and DNA fragmentation was classified (0 to 3+) according to percentage of positive cells and intensity of staining.

RESULTS

Expression of bcl-2 was identified in each CCA examined, and was strongly positive (2+ to 3+) in 18 of 21 samples. Despite the presence of wild-type p53, only 4 of 21 tumors showed evidence of apoptosis as assessed through DNA fragmentation.

CONCLUSIONS

DNA damage leads to increased intracellular p53 levels. Overexpression of p53 induces apoptosis as a means of protecting organisms from the development of malignancy. CCAs of the vagina and cervix, which contain wild-type p53 genes and often overexpress p53 protein, presumably have evolved mechanisms to avoid p53-induced apoptosis. Our observations are consistent with the hypothesis that overexpression of bcl-2 can inhibit p53-mediated apoptosis and suggest a mechanism by which these rare tumors can arise without mutation of the p53 gene.

Cancer risk in women exposed to diethylstilbestrol in utero

CONTEXT

The association between in utero exposure to diethylstilbestrol (DES) and clear cell adenocarcinoma (CCA) of the vagina and cervix is well known, yet there has been no systematic study of DES-exposed daughters to determine whether they have an increased risk of other cancers. As many as 3 million women in the United States may have been exposed to DES in utero.

OBJECTIVE

To determine whether women exposed to DES in utero have a higher risk of cancer after an average of 16 years of follow-up.

DESIGN

A cohort study with mailed questionnaires and medical record review of reported cancer outcomes.

PARTICIPANTS

A cohort of 4536 DES-exposed daughters (of whom 81% responded) and 1544 unexposed daughters (of whom 79% responded) who were first identified in the mid-1970s.

MAIN OUTCOME MEASURES

Cancer incidence in DES-exposed daughters compared with population-based rates and compared with cancer incidence in unexposed daughters.

RESULTS

To date, DES-exposed daughters have not experienced an increased risk for all cancers (rate ratio, 0.96; 95% confidence interval [CI], 0.58-1.56) or for individual cancer sites, except for CCA. Three cases of vaginal CCA occurred among the exposed daughters, resulting in a standardized incidence ratio of 40.7 (95% CI, 13.1-126.2) in comparison with population-based incidence rates. The rate ratio for breast cancer was 1.18 (95% CI, 0.56-2.49); adjustment for known risk factors did not alter this result.

CONCLUSIONS

Thus far, DES-exposed daughters show no increased cancer risk, except for CCA. Nevertheless, because exposed daughters included in our study were, on average, only 38 years old at last follow-up, continued surveillance is warranted to determine whether any increases in cancer risk occur during the menopausal years.

The daughters of diethylstilbestrol. Lessons from an error

Diethylstilbestrol (DES) has been used extensively to prevent pregnancy disorders in Europe but at different levels depending upon the countries. Lessons from the DES story can be learned for research, information for physicians, communication, administration and industry. However, this paper will focus on the incidence of this story in our practice. We will propose guidelines for different conditions: clear cell adenocarcinoma, adenosis, cervical dysplasia, infertility and pregnancy.

Clear cell tumors of the female genital tract

Clear cell adenocarcinomas of the vagina, cervix, endometrium, and ovaries show very similar histological features. Several other tumors and tumor-like lesions of the female genital tract may also contain clear cells and may occasionally be misinterpreted as clear cell adenocarcinomas. These conditions include microglandular hyperplasia, mesonephric hyperplasia, Arias-Stella change, smooth muscle tumors containing clear cells, dysgerminoma, yolk sac tumor, metastatic renal cell carcinoma, steroid cell tumors, hepatoid carcinomas, signet-ring-cell stromal tumors, and trophoblastic tumors. This review discusses the histological features of all of these lesions, emphasizing the morphological aspects that are essential to accurate differential diagnosis.

Clear cell adenocarcinoma of the vagina and cervix. An update of the central Netherlands registry showing twin age incidence peaks

BACKGROUND

The objective of this study was to update the registry of women in the Netherlands with clear cell adenocarcinoma (CCAC) of the cervix or vagina with or without intrauterine exposure to diethylstilbestrol (DES).

METHODS

From a nationwide search in PALGA, the automated pathology registry in the Netherlands, data were gathered on women with CCAC born after 1947. Information obtained from the clinical files of the patients included reported exposure to DES, patterns of complaints previous to diagnosis, the current status of the patients, and the results of cytopathologic examinations previous to histopathologic diagnosis. After review of the histopathologic slides, the specific pathologic characteristics of CCAC were determined. The age distribution of women born after 1947 was compared with that of women born before 1947.

RESULTS

Information about possible exposure to DES during pregnancy was available for 73 of 88 women with CCAC born after 1947. Exposure to DES was reported for 47 (64%) of these women. The DES medication was most often reported as having started before the 18th week of pregnancy. Cytopathologic examination was informative in 81% of the cases of CCAC of the cervix, but only in 41% of the cases of CCAC of the vagina. Most patients had Stage I or II tumors at diagnosis. Tumor Stage III and IV and a high grade of nuclear atypia were related to unfavorable outcome. The age distribution of all patients with CCAC showed two distinct peaks; one at young age, (a mean age of 26 years), and one at older age (a mean age of 71 years). This bimodal age distribution still applied when the cases in which DES exposure was reported had been excluded.

CONCLUSIONS

Despite the fact that DES has not been prescribed to pregnant women in the Netherlands in the last 20 years, CCAC is still relevant in our times. It is important to stay alert and periodically to update and evaluate the data of this registry, including data on women born outside the DES exposure period. The bimodal age distribution in this study of women without intrauterine exposure to DES suggests a carcinogenesis-promoting role of menarche and menopause and/ or the existence of a subpopulation with genetic risk factors or exogenous risk factors other than exposure to DES. Postmenopausal observation of women exposed to DES must be encouraged for clinical reasons and may help facilitate differentiation between these two hypotheses. If these risk factors of CCAC were better documented and their interrelationships better defined, CCAC could become an important model of multistep carcinogenesis in tissues sensitive to sex hormones.

Molecular genetic analysis of clear cell adenocarcinomas of the vagina and cervix associated and unassociated with diethylstilbestrol exposure in utero

BACKGROUND

Prenatal exposure to the synthetic estrogen diethylstilbestrol (DES) is associated with the subsequent development of clear cell adenocarcinoma of the lower reproductive tract in young women, and data concerning the molecular genetic alterations involved in the etiology of this tumor type have not previously been reported. Such knowledge would be of potential value by providing insight into the molecular mechanisms of hormonal carcinogenesis in general, as well as by suggesting molecular markers for risk assessment in the estrogen-exposed population.

METHODS

A total of 24 samples of clear cell adenocarcinoma of the vagina or cervix, 16 associated with exposure in utero to DES and 8 with no history of DES exposure, were obtained as archival fixed and embedded tissue specimens. DNA was purified from these tissues and used to examine a number of biologically plausible molecular genetic endpoints for tumor specific alterations.

RESULTS

No evidence was found for mutations in the K-ras or H-ras protooncogenes, the Wilms' tumor (WT1) tumor suppressor gene, or the estrogen receptor gene. Sporadic overexpression of the p53 tumor suppressor gene was detected in some tumor cell nuclei by immunohistochemistry, but in the absence of detectable p53 gene mutation. Genetic instability as manifested by somatic mutation of microsatellite repeats was widespread in these tumors, with evidence of microsatellite instability in all DES-associated tumors examined, and in 50% of those tumors not associated with DES exposure.

CONCLUSIONS

These data are consistent with the hypothesis that the induction of genomic instability may be an important mechanism of DES-induced carcinogenesis.

[Pregnancy after transposition and repositioning of the ovaries in a patient with clear-cell adenocarcinoma]

A young woman with a history of in utero exposure to distilbestrol was diagnosed with vaginal clear-cell adenocarcinoma. Management consisted of limited excision of the tumor followed by brachytherapy after transposition of the ovaries. The patient had a successful pregnancy after reimplantation of the ovaries in their normal position and right adnexectomy for Chlamydia infection. The child was delivered by cesarean section. This is probably the first case with a pregnancy after repositioning of the ovaries in Europe and perhaps even in the world.

Teratogen update: carcinogenesis and teratogenesis associated with exposure to diethylstilbestrol (DES) in utero

Exposure of the human fetus to physician-prescribed diethylstilbestrol and other synthetic estrogens (collectively referred to as "DES") led to an important iatrogenic epidemic. In the United States alone, at least four million fetuses and their mothers had a substantial exposure to these estrogens now known to be mild carcinogens and potent teratogens. Mothers exposed to DES may have a somewhat higher risk of breast cancer than women who were not exposed. The sequelae of in utero exposure of daughters include clear cell adenocarcinoma of the vagina and cervix, various gross anomalies of the genital tract that are associated with adverse outcomes of pregnancy, vaginal adenosis and other vaginal epithelial changes, and other possible health effects that have not yet been fully evaluated. Among sons exposed in utero to DES, no increase in the incidence of any cancer has been reported, but several anomalies of the genital tract have been described, and it is possible that some social behaviors are modified. Although the grandchildren of the DES-exposed daughters and sons have not been shown to have any abnormalities, some of them have been the products of short gestations. Future research, being funded by the National Cancer Institute, will permit monitoring of the DES-exposed population to determine whether any other abnormalities will become apparent in them.