Abstract P3-10-01: Tamoxifen and contralateral breast cancer (CBC) risk for BRCA1 and BRCA2 mutation carriers: An updated analysis of data from the Kathleen Cuningham Foundation consortium for research into familial breast cancer, the International BRCA1 and BRCA2 Carrier cohort study and the breast cancer family registry

Background: Findings from an analysis published in 2013, using combined retrospective and prospective data pooled from 3 cohort studies, were consistent with tamoxifen use after 1st breast cancer (BC) being associated with reduced CBC risk for both BRCA1 and BRCA2 mutation carriers, although the analysis of prospective data alone (based on 100 incident CBCs) gave inconclusive results. The association did not differ by estrogen receptor (ER) status of the 1st BC, suggesting that tamoxifen may be a useful secondary BC prevention agent for mutation carriers regardless of the ER status of their 1st BC. The aim of this updated analysis was to assess these associations after incorporating data from an additional 1,279 mutation carriers and with further follow-up providing 153 additional prospective CBC events. Methods: Eligible women were BRCA1 and BRCA2 mutation carriers diagnosed with unilateral BC since 1970 and with no other invasive cancer or tamoxifen use before their 1st BC. They were followed up from their 1st BC (or, for the prospective analysis, from the later of recruitment and 1st BC diagnosis) to the development of CBC or censoring (at contralateral mastectomy, death or loss to follow-up). Hazard ratios (HRs) for CBC associated with tamoxifen use were estimated using Cox regression, adjusting for year and age of diagnosis, country and bilateral oophorectomy; analyses were also stratified by ER status of the 1st BC. Results: This 2017 analysis includes 3,743 mutation carriers (BRCA1 2,343; BRCA2 1,400) with 21,436 person years of follow-up. Compared with the 2013 analysis, the strengths of the inverse associations were attenuated after including the additional data.

 2017  2013   TotalCBCHR (95% CI) p-valueTotalCBCHR (95% CI) p-value NN NN BRCA1      Combined*      Tam 1st BC      No17615141.0012003381.00Yes5821290.77 (0.63-0.95) 0.01383350.38 (0.27-0.55) <0.001Prospective      Tam 1st BC      No9841321.00481541.00Yes369400.82 (0.57-1.20) 0.31176120.58 (0.29-1.13) 0.1BRCA2      Combined*      Tam1st BC      No6361661.004271151.00Yes764990.58 (0.44-0.76) <0.001454320.33 (0.22-0.50) <0.001Prospective      Tam 1st BC      No389461.00191211.00Yes497350.68 (0.40-1.15) 0.15235130.48 (0.22-1.05) 0.07*Combined = retrospective and prospective, N=number, BRCA1 & BRCA2=mutation carriers, Tam 1st BC= Tamoxifen for 1st Breast Cancer

In this updated prospective analysis, the inverse association between tamoxifen use for 1st BC and CBC risk was most apparent for women with ER positive 1st BC, especially for BRCA2 mutation carriers: BRCA1 ER positive HR=0.45 (95% CI 0.17-1.22, p=0.12), BRCA1 ER negative HR= 0.87 (95% CI 0.45-1.67, p=0.67), BRCA2 ER positive HR=0.33 (95% CI 0.15-0.74, p<0.007), BRCA2 ER negative HR=1.12 (95% CI 0.27-4.70, p=0.88).

Conclusions: Tamoxifen use for 1st BC might reduce CBC risk for mutation carriers, but predominantly for those with an ER positive 1st BC. These data do not support use of tamoxifen to prevent CBC for mutation carriers with ER negative BC.

Citation Format: Phillips K-A, Milne RL, Bassett JK, Hopper JL, Buys SS, Daly MB, Hooning MJ, Mooij TM, Andrieu N, Antoniou AC, Rookus MA, Easton DF, Mary-Beth T. Tamoxifen and contralateral breast cancer (CBC) risk for BRCA1 and BRCA2 mutation carriers: An updated analysis of data from the Kathleen Cuningham Foundation consortium for research into familial breast cancer, the International BRCA1 and BRCA2 Carrier cohort study and the breast cancer family registry [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-10-01.

Abstract P5-08-09: Use of oral contraceptives and risk of breast cancer in BRCA1 and BRCA2 mutation carriers: An international prospective cohort study; for the studies of EMBRACE, GENEPSO, HEBON, kConFab and BCFR

This abstract was withdrawn by the authors.

Melanoma risk after ovarian stimulation for in vitro fertilization

STUDY QUESTION

Do women treated with ovarian stimulation for IVF have an increased risk of melanoma?

SUMMARY ANSWER

Ovarian stimulation for IVF does not increase risk of melanoma, even after a prolonged follow-up.

WHAT IS KNOWN ALREADY

Although exposure to ultraviolet radiation is the major risk factor for melanoma, associations between female sex steroids and melanoma risk have also been suggested. The results of available studies on fertility drugs and melanoma risk are inconclusive since most studies had several methodological limitations such as short follow-up, a small number of cases and no subfertile comparison group.

STUDY DESIGN, SIZE, DURATION

In 1996, a nationwide historic cohort study (the OMEGA-cohort) was established to examine the risk of cancer after ovarian stimulation for IVF. After a median follow-up of 17 years, cancer incidence was ascertained through linkage with the Netherlands Cancer Registry. Melanoma risk in the cohort was compared with that in the general population and between the IVF group and non-IVF group using multivariable Cox regression analyses.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The cohort comprises 19 158 women who received IVF between 1983 and 1995 and a comparison group of 5950 women who underwent subfertility treatments other than IVF. Detailed IVF-treatment data were obtained from the medical records and complete information on parity and age at first birth was obtained through linkage with the Dutch Municipal Personal Records Database.

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 93 melanoma cases were observed. The risk of melanoma was not elevated among IVF-treated women, neither when compared with the general population (standardized incidence ratio = 0.89; 95% confidence interval (CI): 0.69-1.12), nor when compared with the non-IVF group (adjusted hazard ratio (HR) = 1.27; 95% CI: 0.75-2.15). A higher number of IVF cycles was associated with apparent but statistically non-significant risk increases (5-6 cycles HR = 1.92; ≥7 cycles HR = 1.79). However, no significant trend emerged. In women with more follicle stimulating hormone/human menopausal gonadotrophin ampoules comparable non-significant risk increases were found. A longer follow-up did not increase melanoma risk. Nulliparous women did not have a significantly higher melanoma risk than parous women (HR = 1.22; 95% CI: 0.81-1.84). However, women who were 30 years of age or older at first birth had a significantly higher melanoma risk than women who were younger than 30 years at first birth (age: 30-34 years HR = 4.57; 95% CI: 2.07-10.08, >34 years HR = 2.98; 95% CI: 1.23-7.21).

LIMITATIONS, REASONS FOR CAUTION

Despite our large cohort, the number of melanoma cases was rather small, especially in our comparison group, which hampered subgroup analyses.

WIDER IMPLICATIONS OF THE FINDINGS

Our results are reassuring for women who underwent IVF or are contemplating to start IVF. Since our cohort study is one of the largest published so far, with long-term follow-up, a subfertile comparison group, and detailed IVF-treatment data, our results add important information to the available evidence.

STUDY FUNDING/COMPETING INTEREST

This study was supported by grants from the Dutch Cancer Society (NKI 2006-3631), the Health Research and Development Counsel (28-2540) and the Dutch Ministry of Health.

Increased risk for ovarian cancer and borderline ovarian tumours in subfertile women with endometriosis

STUDY QUESTION

Is ovarian or extra-ovarian endometriosis associated with an increased risk of ovarian cancer and borderline ovarian tumours (BOT)?

SUMMARY ANSWER

We found a 3- to 8-fold increased risk of ovarian tumours associated with endometriosis: the magnitude of the risk increase depended on the definition of endometriosis.

WHAT IS KNOWN ALREADY

There is increasing evidence of an association between endometriosis and increased risk of ovarian cancer. However, most reports were based on self-reported diagnosis of endometriosis.

STUDY DESIGN, SIZE, DURATION

We conducted a nationwide historic cohort study among women with subfertility problems between 1980 and 1995. For this analysis we selected all cohort members with endometriosis, and a comparison group of subfertile women (male factor or idiopathic) without endometriosis (total cohort of 8904 women). Median follow-up time was 15.2 for the entire study population.

PARTICIPANTS/MATERIALS, SETTING, METHODS

For this analysis we selected all cohort members with (n = 3657) and without (n = 5247) evidence of endometriosis. Seventy-eight per cent of diagnoses of endometriosis were confirmed by pathology report, and 22% was self-reported endometriosis (positive predictive value of 73%). We linked the cohort with the Dutch Pathology Database and the Netherlands Cancer Registry to assess the occurrence of ovarian cancer and BOT between January 1989 and June 2007.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed a substantially increased risk of all ovarian malignancies combined in women with endometriosis when we based the definition of endometriosis on self-report, medical records information at subfertility treatment and/or the nationwide pathology database (hazard ratio (HR) 8.2; 95% confidence interval (CI) 3.1-21.6). The HR associated with endometriosis was 12.4 (95% CI 2.8-54.2) for ovarian cancer and 5.5 (95% CI 1.5-20.2) for BOT. When we excluded information from the pathology database, HRs were 3.0 (95% CI 1.5-6.1) for all ovarian tumours, 4.3 (95% CI 1.6-11.2) for ovarian cancer and 1.9 (95% CI 0.6-5.8) for BOT. Both ovarian and extra-ovarian endometriosis carried a significantly increased risk for ovarian cancer and BOT.

LIMITATIONS, REASONS FOR CAUTION

We did not have information on oral contraceptive use and parity for 23.4 and 3.4%, of women in the analytic cohort, respectively. Furthermore, a limitation of our study, and also of other studies, is that the date of diagnosis of endometriosis is usually made long after the onset of the disease. Also, the number of cases in the cohort is small (n = 34), resulting in wide CIs.

WIDER IMPLICATIONS OF THE FINDINGS

The fact that endometriosis was assessed before diagnosis of ovarian malignancy and the high degree of medical confirmation in our study likely contribute to the validity of our estimate of a 3- to 8-fold increased risk of ovarian tumours associated with endometriosis. The risk of ovarian malignancies associated with endometriosis was much higher in analyses including information on endometriosis from the nationwide pathology database, implying that risk estimates from studies using self-reported information on endometriosis may be too low due to non-differential misclassification bias.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

None.

Factors associated with dizygotic twinning after IVF treatment with double embryo transfer

BACKGROUND

Dizygotic twin pregnancies after IVF treatment are the result of multiple embryos transferred into the uterine cavity, followed by successful double implantation. Factors that increase the chance of multiple implantation after IVF are relatively unknown. The present study aimed to investigate whether features of body composition, such as maternal height, weight and body mass index (BMI) are associated with an increased chance of dizygotic twinning after IVF with double embryo transfer (DET).

METHODS

This study was conducted using data from a large Dutch nationwide cohort that comprised 19 861 women who had IVF or ICSI treatment between 1983 and 1995 (OMEGA study). First 'fresh' IVF and ICSI cycles with DET resulting in a delivery of a singleton or twin (living as well as stillborn) were selected. A multivariable logistic regression analysis was performed, with the delivery of a singleton or twin as the dependent variable and height, weight, BMI, maternal age, number of retrieved oocytes, use of alcohol, smoking, highest level of education and parity as independent variables.

RESULTS

Of the 6598 women who completed their first IVF or ICSI cycle, 2375 had DET, resulting in 496 deliveries of 371 singletons and 125 twins. Multivariable regression analysis revealed that tall women (>1.74 cm) and women with a high number of retrieved oocytes (>8) had an increased chance of dizygotic twinning [OR: 1.8 (95% CI: 1.0-3.4) and OR: 2.2 (95% CI: 1.3-3.8), respectively].

CONCLUSIONS

Our data demonstrate that tall stature and increased number of retrieved oocytes independently increase the chance of dizygotic twinning after IVF with DET.

Risk of borderline and invasive ovarian tumours after ovarian stimulation for in vitro fertilization in a large Dutch cohort

BACKGROUND

Long-term effects of ovarian stimulation for IVF on the risk of ovarian malignancies are unknown.

METHODS

We identified a nationwide historic cohort of 19,146 women who received IVF treatment in the Netherlands between 1983 and 1995, and a comparison group of 6006 subfertile women not treated with IVF. In 1997-1999, data on reproductive risk factors were obtained from 65% of women and data on subfertility (treatment) were obtained from the medical records. The incidence of ovarian malignancies (including borderline ovarian tumours) through 2007 was assessed through linkage with disease registries. The risk of ovarian malignancies in the IVF group was compared with risks in the general population and the subfertile comparison group.

RESULTS

After a median follow-up of 14.7 years, the risk of borderline ovarian tumours was increased in the IVF group compared with the general population [standardized incidence ratio (SIR) = 1.76; 95% confidence interval (CI) = 1.16-2.56]. The overall SIR for invasive ovarian cancer was not significantly elevated, but increased with longer follow-up after first IVF (P = 0.02); the SIR was 3.54 (95% CI = 1.62-6.72) after 15 years. The risks of borderline ovarian tumours and of all ovarian malignancies combined in the IVF group were significantly increased compared with risks in the subfertile comparison group (hazard ratios = 4.23; 95% CI = 1.25-14.33 and 2.14; 95% CI = 1.07-4.25, respectively, adjusted for age, parity and subfertility cause).

CONCLUSIONS

Ovarian stimulation for IVF may increase the risk of ovarian malignancies, especially borderline ovarian tumours. More large cohort studies are needed to confirm these findings and to examine the effect of IVF treatment characteristics.

Maternal death related to IVF in the Netherlands 1984-2008

BACKGROUND

We assessed all deaths in the Netherlands that might have been related to IVF or to an IVF pregnancy in order to investigate this most serious complication.

METHODS

All deaths related to IVF, within 1 year after IVF, from 1984 to 2008 were collected by sending a letter to all gynaecologists, and by retrieving data from a large cohort study examining the late effects of ovarian stimulation (OMEGA) and from the Dutch Maternal Mortality Committee.

RESULTS

Six deaths were directly related to IVF (6/100,000), 17 deaths were directly related to the IVF pregnancy (42.5/100,000) and eight deaths were neither related to the IVF nor to the IVF-related pregnancy. The overall mortality in patients undergoing IVF procedures was lower than in the general population, whereas the overall mortality related to IVF pregnancies was higher than the maternal mortality in the general population.

CONCLUSION

The decreased mortality is probably the result of a 'healthy female effect' in women undergoing IVF. The high maternal mortality in IVF pregnancies is probably related to the high number of multiple pregnancies and to the fact that (donor egg) IVF is successfully used in women who are older. The fact that only a few deaths directly related to IVF are reported in the literature whereas we observed six in the Netherlands indicates worldwide under-reporting of IVF-related mortality. We underline the importance of reporting all lethal cases to the European Society of Human Reproduction and Embryology Committee 'Safety and Quality after IVF'.

No efficacy of annual gynaecological screening in BRCA1/2 mutation carriers; an observational follow-up study

BRCA1/2 mutation carriers are offered gynaecological screening with the intention to reduce mortality by detecting ovarian cancer at an early stage. We examined compliance and efficacy of gynaecological screening in BRCA1/2 mutation carriers. In this multicentre, observational, follow-up study we examined medical record data of a consecutive series of 888 BRCA1/2 mutation carriers who started annual screening with transvaginal ultrasonography and serum CA125 between 1993 and 2005. The women were annually screened for 75% of their total period of follow-up. Compliance decreased with longer follow-up. Five of the 10 incident cancers were interval tumours, diagnosed in women with a normal screening result within 3–10 months before diagnosis. No difference in stage distribution between incident screen-detected and interval tumours was found. Eight of the 10 incident cancers were stage III/IV (80%). Cancers diagnosed in unscreened family members had a similar stage distribution (77% in stage III/IV). The observed number of cases detected during screening was not significantly higher than expected (Standardized Incidence Ratio (SIR): 1.5, 95% confidence interval: 0.7–2.8). For the subgroup that was fully compliant to annual screening, a similar SIR was found (1.6, 95% confidence interval: 0.5–3.6). Despite annual gynaecological screening, a high proportion of ovarian cancers in BRCA1/2 carriers are interval cancers and the large majority of all cancers are diagnosed in advanced stages. Therefore, it is unlikely that annual screening will reduce mortality from ovarian cancer in BRCA1/2 mutation carriers.

Clinical outcome of prophylactic oophorectomy in BRCA1/BRCA2 mutation carriers and events during follow-up

A retrospective study was performed to assess the histopathologic findings in high-risk women undergoing bilateral prophylactic (salpingo)-oophorectomy. The medical files of BRCA1 or BRCA2 mutation carriers and members of a hereditary breast/ovarian cancer (HBOC) family, who had undergone prophylactic surgery, were reviewed. In all, 38 women underwent a bilateral oophorectomy (26 BRCA1, three BRCA2 and nine HBOC, respectively). A total of 90 women underwent bilateral salpingo-oophorectomy (58 BRCA1, six BRCA2, one BRCA1 and 2, 25 HBOC, respectively). At the time of salpingo-oophorectomy, five of 58 BRCA1 carriers (8.6%) were diagnosed with an occult carcinoma: two fallopian tube carcinomas, two ovarian carcinomas and one case was defined as a fallopian tube/ovarian carcinoma. No occult carcinomas were found in the other groups. Of the 38 patients, who underwent a bilateral oophorectomy (mean follow-up 45 months), three of 26 BRCA1 mutation carriers (3.4 in 100 women-years) developed peritoneal papillary serous carcinoma (PPSC) during follow-up. So far, no PPSC have occurred in the 90 women, who underwent a salpingo-oophorectomy (mean follow-up 12 months), including 58 BRCA1 carriers (0 in 60 in women-years). These results contribute to the thesis that BRCA1 germline mutation carriers are not only at risk for ovarian cancer, but also for fallopian tube carcinoma and peritoneal papillary serous carcinoma. Our data suggest that PPSC risk among BRCA2 carriers is lower than among BRCA1 carriers.

Promoting prosocial pupil behaviour: 2-secondary school intervention and pupil effects

BACKGROUND

In an earlier article (Mooij, 1999c) a theoretical multilevel model to promote prosocial pupil behaviour by stimulating specific educational conditions was developed.

AIMS

To carry out school interventions to check empirically whether pupil level effects occur because of educational changes at the classroom and school level.

SAMPLES

Seven secondary schools with relatively high degrees of pupil aggression were selected. Four schools took part as intervention schools, three schools served as control schools. In 1995 (pretest) and 1997 (post-test) pupils and form teachers of the first and third school years participated by completing questionnaires. Within the pupil cohorts, a longitudinal group of 352 pupils was included.

METHODS

Pretest questionnaires in 1995 were followed by intervention in the intervention schools. Teachers collaborated with staff and researchers to increase pupils' participation and responsibility in specifying and controlling behavioural and didactic rules, related to didactic differentiation during lessons. The validity of the intervention implementation was checked using qualitative information and quantitative data from both pre- and post-test. Longitudinal intervention effects were tested by applying two-level multiple regression analyses.

RESULTS

After controlling for pretest and covariables in school year 1, school intervention effects were found in school year 3 with the prediction of being a perpetrator of aggressive behaviour at school, aggressive behaviour outside school, and criminal behaviour. Some small effects were found with respect to victim behaviour.

CONCLUSIONS

Social-pedagogical and didactic class and school variables, but also home variables and support by peers without problematic behaviour, could be integrated more systematically to promote prosocial development of a pupil's behaviour from the beginning in school.

Pupil-class determinants of aggressive and victim behaviour in pupils

BACKGROUND

Aggressive behaviour in pupils is expressed in, e.g., bullying, sexual harassment, and violence. Different kinds of variables could be relevant in explaining a pupil's aggressive or victim behaviour.

AIMS

To develop a multilevel theoretical and empirical explanation for different kinds of aggressive and victim behaviour displayed by pupils in a classroom and school environment.

SAMPLES

A national survey was carried out to identify different kinds of aggressive and victim behaviour displayed by pupils and to assess other variables related to pupils, classes, and schools. A total of 1998 pupils from 100 third and fourth year classes attending 71 different secondary schools took part in the research.

METHODS

Data were analysed by a series of secondary multilevel analyses using the MLA-program.

RESULTS

Being a boy, being more extravert, being more disagreeable, coming across fewer teachers with positive teaching behaviour, and attending a lower type of secondary school, help explain why someone is a perpetrator as such. Being a boy, being more disagreeable, being more emotionally unstable, being open to new ideas, and seeing more teachers as being strict, function as explanatory pupil variables for victim behaviour. Other pupil level variables determine more specific aggressive and victim behaviour aspects. Various other class level and school level variables are relevant, too.

CONCLUSIONS

Personal and environmental pupil variables are more important than class variables but class variables are in turn more important than school variables in explaining a pupil's aggressive and victim behaviour.

Influence of pressure alterations on tone and vasomotion of isolated mesenteric small arteries of the rat

1. Myogenic responses may account for control of organ blood flow. The study of these responses without interference from the organ requires an isolation technique for vessels which contribute significantly to flow resistance. This study reports on experiments on isolated small mesenteric arteries. 2. Distal rat mesenteric arcade arteries and first-order branches (diameter range 145-365 microns, mean 293 microns) were manually dissected and cannulated using a double-barrelled micro-cannula. Luminal cross-sectional area of these vessels was continuously monitored by means of a fluorescence technique. 3. Nine out of eighteen vessels developed basal tone at 80 mmHg distending pressure, resulting in a 45.2 +/- 5.1% (mean +/- S.E.M) decrease of cross-sectional area. Tone was induced in the other vessels by 0.3-1 microM-noradrenaline, resulting in a 59.5 +/- 7.1% decrease in cross-sectional area. 4. In vessels with either spontaneous or induced tone, stepwise changes of pressure resulted in passive effects, followed by myogenic responses. 5. Steady-state pressure-cross-sectional area relations of vessels with basal tone showed a significant negative slope (-0.5% mmHg-1), while pressure-cross-sectional area relations of vessels with induced tone were essentially flat between 40 and 120 mmHg. 6. Five vessels with basal tone and eight vessels with induced tone developed vasomotion at 80 mmHg. Frequencies of spontaneous and induced vasomotion were 14 (range 4-31) and 21 (9-25) cycles min-1 respectively. Amplitudes were 5 (1-10) and 8 (3-17)% of the passive cross-sectional area. In both groups, frequency was positively, and amplitude negatively correlated with pressure. 7. These data show that myogenic responses are induced by wall stress, rather than by distension of the vascular wall. Basal tone is not a prerequisite for the appearance of myogenic responses.

Cannulation and continuous cross-sectional area measurement of small blood vessels

Techniques have been developed for the study of isolated small arteries. To pressurize and perfuse segments of these vessels, a cannula with a low resistance to flow was developed. This cannula consisted of two concentric micropipettes. The end of a vessel segment was sucked into the inner pipette and clamped by applying subatmospheric pressure on the outer pipette. Subsequently, the vessel was pressurized via the inner pipette. To enable perfusion, the segment was cannulated at both ends. Mean cross-sectional area (CSA) of the cannulated segments was continuously measured using a fluorescence technique. The emission of light by fluorescein isothiocyanate (FITC) labeled dextran in the vessel lumen was measured using a photomultiplier tube (PMT). PMT current was linearly related to the vessel CSA. Twenty-nine rat mesenteric vessels with inside diameters ranging from 110 to 350 microns (mean 226 microns) when maximally dilated at 80 mm Hg were cannulated. CSA was monitored during variations in perfusion pressure and addition of vasoactive agents.