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Featured researches published by Helena Schock.


European Radiology | 2007

Value of MR phase-contrast flow measurements for functional assessment of pulmonary arterial hypertension.

Sebastian Ley; Derliz Mereles; Michael Puderbach; Ekkehard Gruenig; Helena Schock; Monika Eichinger; Julia Ley-Zaporozhan; Christian Fink; Hans-Ulrich Kauczor

Goals of our study were to compare the pulmonary hemodynamics between healthy volunteers and patients with pulmonary arterial hypertension (PAH) and correlate MR flow measurements with echocardiography. Twenty-five patients with PAH and 25 volunteers were examined at 1.5 T. Phase-contrast flow measurements were performed in the ascending aorta and pulmonary trunk, resulting in the following parameters: peak velocity (cm/s), average blood flow (l/min), time to peak velocity (ms), velocity rise gradient and pulmonary distensibility (cm2). The bronchosystemic shunt was calculated. In PAH patients transthoracic echocardiography and right-heart catheterization (RHC) served as the gold standard. In comparison to volunteers, the PAH patients showed significantly reduced pulmonary velocities (P = 0.002), blood flow (P = 0.002) and pulmonary distensibility (P = 0.008). In patients, the time to peak velocity was shorter (P<0.001), and the velocity rise gradient was steeper (P = 0.002) than in volunteers. While in volunteers the peak velocity in the aorta was reached earlier, it was the reverse in patients. Patients showed a significant bronchosystemic shunt (P = 0.01). No meaningful correlation was found between MRI measurements and echocardiography or RHC. MRI is a feasible technique for the differentiation between PAH and volunteers. Further studies have to be conducted for the absolute calculation of pressure estimates.


Obstetrics & Gynecology | 2011

Determinants of maternal sex steroids during the first half of pregnancy.

Adetunji T. Toriola; Marja Vääräsmäki; Matti Lehtinen; Anne Zeleniuch-Jacquotte; Eva Lundin; Kenneth-Gary Rodgers; Hans-Åke Lakso; Tianhui Chen; Helena Schock; Göran Hallmans; Eero Pukkala; Paolo Toniolo; Kjell Grankvist; Heljä-Marja Surcel; Annekatrin Lukanova

OBJECTIVE: To examine the associations of maternal and child characteristics with early pregnancy maternal concentrations of testosterone, androstenedione, progesterone, 17-hydroxyprogesterone, and estradiol (E2). METHODS: We analyzed these hormones among 1,343 women with singleton pregnancies who donated serum samples to the Finnish Maternity Cohort from 1986 to 2006 during the first half of pregnancy (median 11 weeks). The associations of maternal and child characteristics with hormone concentrations were investigated by correlation and multivariable regression. RESULTS: Women older than age 30 years had lower androgen and E2 but higher progesterone concentrations than women younger than that age. Multiparous women had 14% lower testosterone, 11% lower androstenedione and 17-hydroxyprogesterone, 9% lower progesterone, and 16% lower E2 concentrations compared with nulliparous women (all P<.05). Smoking mothers had 11%, 18%, and 8% higher testosterone, androstenedione, and 17-hydroxyprogesterone levels, respectively, but 10% lower progesterone compared with nonsmoking women (all P<.05). E2 concentrations were 9% higher (P<.05) among women with a female fetus compared with those with a male fetus. CONCLUSION: Parity, smoking, and, to a lesser extent, maternal age and child sex are associated with sex steroid levels during the first half of a singleton pregnancy. The effects of smoking on the maternal hormonal environment and the possible long-term deleterious consequences on the fetus deserve further evaluation. LEVEL OF EVIDENCE: II


International Journal of Cancer | 2014

Premenopausal serum sex hormone levels in relation to breast cancer risk, overall and by hormone receptor status - results from the EPIC cohort.

Rudolf Kaaks; Kaja Tikk; Disorn Sookthai; Helena Schock; Theron Johnson; Anne Tjønneland; Anja Olsen; Kim Overvad; Françoise Clavel-Chapelon; Laure Dossus; Laura Baglietto; Sabina Rinaldi; Véronique Chajès; Isabelle Romieu; Heiner Boeing; Madlen Schütze; Antonia Trichopoulou; Pagona Lagiou; Dimitrios Trichopoulos; Domenico Palli; Sabina Sieri; Rosario Tumino; Fulvio Ricceri; Amalia Mattiello; Genevieve Buckland; José Ramón Quirós; María José Sánchez; Pilar Amiano; Maria Dolores Chirlaque; Aurelio Barricarte

Results from prospective studies on premenopausal serum hormone levels in relation to breast cancer risk have been inconclusive, especially with regard to tumor subtypes. Using a case–control study nested within the prospective European Prospective Investigation into Cancer and Nutrition (EPIC) cohort (801 breast cancer cases and 1,132 matched control subjects), we analyzed the relationships of prediagnostic serum estradiol, free estradiol, progesterone, testosterone, free testosterone and sex hormone‐binding globulin (SHBG) levels with the risk of breast cancer by estrogen and progesterone receptor‐positive and ‐negative breast tumors and by age at diagnoses. Higher prediagnostic serum levels of testosterone and free testosterone were associated with an increased overall risk of breast cancer [ORQ4‐Q1 = 1.56 (95% CI 1.15–2.13), ptrend = 0.02 for testosterone and ORQ4‐Q1 = 1.33 (95% CI 0.99–1.79), ptrend = 0.04 for free testosterone], but no significant risk association was observed for estradiol, free estradiol, progesterone and SHBG. Tests for heterogeneity between receptor‐positive and ‐negative tumors were not significant. When analysis were stratified by age at tumor diagnosis, the odds ratios observed for estradiol were stronger and borderline significant for breast cancer diagnosed at age less than 50 [ORQ4‐Q1 = 1.32 (95% CI 0.87–2.01), ptrend = 0.05] compared to breast cancer diagnosed at age 50 or above [ORQ4‐Q1 = 0.94 (95% CI 0.60–1.47), ptrend = 0.34, phet = 0.04]. In conclusion, our data indicate that higher premenopausal circulating testosterone levels are associated with an increased risk of developing breast cancer, but do not show a significant association of estradiol or progesterone with breast cancer risk, overall, by menstrual cycle phase or by tumor receptor status, although a possible risk increase with higher estradiol levels for tumors diagnosed before age 50 was seen.


Cancer Research | 2010

Human Chorionic Gonadotropin in Pregnancy and Maternal Risk of Breast Cancer

Paolo Toniolo; Kjell Grankvist; Marianne Wulff; Tianhui Chen; Robert Johansson; Helena Schock; Per Lenner; Göran Hallmans; Matti Lehtinen; Rudolf Kaaks; Göran Wadell; Anne Zeleniuch-Jacquotte; Eva Lundin; Annekatrin Lukanova

Full-term pregnancies are associated with long-term reductions in maternal risk of breast cancer, but the biological determinants of the protection are unknown. Experimental observations suggest that human chorionic gonadotropin (hCG), a major hormone of pregnancy, could play a role in this association. A case-control study (242 cases and 450 controls) nested within the Northern Sweden Maternity Cohort included women who had donated a blood sample during the first trimester of a first full-term pregnancy. Total hCG was determined on Immulite 2000 analyzer. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through conditional logistic regression. Maternal breast cancer risk decreased with increasing hCG (upper tertile OR, 0.67; CI, 0.46-0.99), especially for pregnancies before age 25 (upper tertile OR, 0.41; CI, 0.21-0.80). The association diverged according to age at diagnosis: risk was reduced after age 40 (upper tertile OR, 0.60; CI, 0.39-0.91) and seemed to increase before age 40 (upper tertile OR, 1.78; CI, 0.72-4.38). Risk was reduced among those diagnosed 10 years or longer after blood draw (upper tertile OR, 0.60; CI, 0.40-0.90), but not so among those diagnosed within 10 years (upper tertile OR, 4.33; CI, 0.86-21.7). These observations suggest that the association between pregnancy hCG and subsequent maternal risk of breast cancer is modified by age at diagnosis. Although the hormone seems to be a determinant of the reduced risk around or after age 50, it might not confer protection against, or it could even increase the risk of, cancers diagnosed in the years immediately following pregnancy.


International Journal of Cancer | 2012

Circulating estrogens and progesterone during primiparous pregnancies and risk of maternal breast cancer

Annekatrin Lukanova; Helja Marja Surcel; Eva Lundin; Marjo Kaasila; Hans-Åke Lakso; Helena Schock; Anika Hüsing; Rudolf Kaaks; Pentti Koskela; Kjell Grankvist; Eero Pukkala; Anne Zeleniuch-Jacquotte; Matti Lehtinen; Paolo Toniolo

Pregnancy reduces maternal risk of breast cancer in the long term, but the biological determinants of the protection are unknown. Animal experiments suggest that estrogens and progesterone could be involved, but direct human evidence is scant. A case‐control study (536 cases and 1,049 controls) was nested within the Finnish Maternity Cohort. Eligible were primiparous women who delivered at term a singleton offspring before age 40. For each case, two individually matched controls by age (±6 months) and date of sampling (±3 months) were selected. Estradiol, estrone and progesterone in first‐trimester serum were measured by high‐performance liquid chromatography tandem mass spectrometry and sex‐hormone binding globulin (SHBG) by immunoassay. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through conditional logistic regression. In the whole study population there was no association of breast cancer with any of the studied hormones. In analyses stratified by age at diagnosis, however, estradiol concentrations were positively associated with risk of breast cancer before age 40 (upper quartile OR, 1.81; CI, 1.08–3.06), but inversely associated with risk in women who were diagnosed ≥age 40 (upper quartile OR, 0.64; CI, 0.40–1.04), pinteraction 0.004. Risk estimates for estrone mirrored those for estradiol but were less pronounced. Progesterone was not associated with risk of subsequent breast cancer. Our results provide initial evidence that concentrations of estrogens during the early parts of a primiparous pregnancy are associated with maternal risk of breast cancer and suggest that the effect may differ for tumors diagnosed before and after age 40.


International Journal of Cancer | 2015

Reproductive and hormone-related risk factors for epithelial ovarian cancer by histologic pathways, invasiveness and histologic subtypes: Results from the EPIC cohort

Renée T. Fortner; Jennifer Ose; Melissa A. Merritt; Helena Schock; Anne Tjønneland; Louise Hansen; Kim Overvad; Laure Dossus; Françoise Clavel-Chapelon; Laura Baglietto; Heiner Boeing; Antonia Trichopoulou; Vassiliki Benetou; Pagona Lagiou; Claudia Agnoli; Amalia Mattiello; Giovanna Masala; Rosario Tumino; Carlotta Sacerdote; H. B. Bueno-de-Mesquita; N. Charlotte Onland-Moret; Petra H.M. Peeters; Elisabete Weiderpass; Inger Torhild Gram; Eric J. Duell; Nerea Larrañaga; Eva Ardanaz; María José Sánchez; M. D. Chirlaque; Jenny Brändstedt

Whether risk factors for epithelial ovarian cancer (EOC) differ by subtype (i.e., dualistic pathway of carcinogenesis, histologic subtype) is not well understood; however, data to date suggest risk factor differences. We examined associations between reproductive and hormone‐related risk factors for EOC by subtype in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Among 334,126 women with data on reproductive and hormone‐related risk factors (follow‐up: 1992–2010), 1,245 incident cases of EOC with known histology and invasiveness were identified. Data on tumor histology, grade, and invasiveness, were available from cancer registries and pathology record review. We observed significant heterogeneity by the dualistic model (i.e., type I [low grade serous or endometrioid, mucinous, clear cell, malignant Brenner] vs. type II [high grade serous or endometrioid]) for full‐term pregnancy (phet = 0.02). Full‐term pregnancy was more strongly inversely associated with type I than type II tumors (ever vs. never: type I: relative risk (RR) 0.47 [95% confidence interval (CI): 0.33–0.69]; type II, RR: 0.81 [0.61–1.06]). We observed no significant differences in risk in analyses by major histologic subtypes of invasive EOC (serous, mucinous, endometrioid, clear cell). None of the investigated factors were associated with borderline tumors. Established protective factors, including duration of oral contraceptive use and full term pregnancy, were consistently inversely associated with risk across histologic subtypes (e.g., ever full‐term pregnancy: serous, RR: 0.73 [0.58–0.92]; mucinous, RR: 0.53 [0.30–0.95]; endometrioid, RR: 0.65 [0.40–1.06]; clear cell, RR: 0.34 [0.18–0.64]; phet = 0.16). These results suggest limited heterogeneity between reproductive and hormone‐related risk factors and EOC subtypes.


Clinical Cancer Research | 2016

A Prospective Evaluation of Early Detection Biomarkers for Ovarian Cancer in the European EPIC Cohort.

Kathryn L. Terry; Helena Schock; Renée T. Fortner; Anika Hüsing; Raina N. Fichorova; Hidemi S. Yamamoto; Allison F. Vitonis; Theron Johnson; Kim Overvad; Anne Tjønneland; Marie-Christine Boutron-Ruault; Sylvie Mesrine; Gianluca Severi; Laure Dossus; Sabina Rinaldi; Heiner Boeing; Vassiliki Benetou; Pagona Lagiou; Antonia Trichopoulou; Vittorio Krogh; Elisabetta Kuhn; Salvatore Panico; H. Bas Bueno-de-Mesquita; N. Charlotte Onland-Moret; Petra H.M. Peeters; Inger Torhild Gram; Elisabete Weiderpass; Eric J. Duell; María José Sánchez; Eva Ardanaz

Purpose: About 60% of ovarian cancers are diagnosed at late stage, when 5-year survival is less than 30% in contrast to 90% for local disease. This has prompted search for early detection biomarkers. For initial testing, specimens taken months or years before ovarian cancer diagnosis are the best source of information to evaluate early detection biomarkers. Here we evaluate the most promising ovarian cancer screening biomarkers in prospectively collected samples from the European Prospective Investigation into Cancer and Nutrition study. Experimental Design: We measured CA125, HE4, CA72.4, and CA15.3 in 810 invasive epithelial ovarian cancer cases and 1,939 controls. We calculated the sensitivity at 95% and 98% specificity as well as area under the receiver operator curve (C-statistic) for each marker individually and in combination. In addition, we evaluated marker performance by stage at diagnosis and time between blood draw and diagnosis. Results: We observed the best discrimination between cases and controls within 6 months of diagnosis for CA125 (C-statistic = 0.92), then HE4 (0.84), CA72.4 (0.77), and CA15.3 (0.73). Marker performance declined with longer time between blood draw and diagnosis and for earlier staged disease. However, assessment of discriminatory ability at early stage was limited by small numbers. Combinations of markers performed modestly, but significantly better than any single marker. Conclusions: CA125 remains the single best marker for the early detection of invasive epithelial ovarian cancer, but can be slightly improved by combining with other markers. Identifying novel markers for ovarian cancer will require studies including larger numbers of early-stage cases. Clin Cancer Res; 22(18); 4664–75. ©2016 AACR. See related commentary by Skates, p. 4542


International Journal of Cancer | 2015

Reproductive and hormone-related risk factors for epithelial ovarian cancer by histologic pathways, invasiveness and histologic subtypes

Renée T. Fortner; Jennifer Ose; Melissa A. Merritt; Helena Schock; Anne Tjønneland; Louise Hansen; Kim Overvad; Laure Dossus; Françoise Clavel-Chapelon; Laura Baglietto; Heiner Boeing; Antonia Trichopoulou; Vassiliki Benetou; Pagona Lagiou; Claudia Agnoli; Amalia Mattiello; Giovanna Masala; Rosario Tumino; Carlotta Sacerdote; H. B. Bueno-de-Mesquita; N. Charlotte Onland-Moret; Petra H.M. Peeters; Elisabete Weiderpass; Inger Torhild Gram; Eric J. Duell; Nerea Larrañaga; Eva Ardanaz; María José Sánchez; M. D. Chirlaque; Jenny Brändstedt

Whether risk factors for epithelial ovarian cancer (EOC) differ by subtype (i.e., dualistic pathway of carcinogenesis, histologic subtype) is not well understood; however, data to date suggest risk factor differences. We examined associations between reproductive and hormone‐related risk factors for EOC by subtype in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Among 334,126 women with data on reproductive and hormone‐related risk factors (follow‐up: 1992–2010), 1,245 incident cases of EOC with known histology and invasiveness were identified. Data on tumor histology, grade, and invasiveness, were available from cancer registries and pathology record review. We observed significant heterogeneity by the dualistic model (i.e., type I [low grade serous or endometrioid, mucinous, clear cell, malignant Brenner] vs. type II [high grade serous or endometrioid]) for full‐term pregnancy (phet = 0.02). Full‐term pregnancy was more strongly inversely associated with type I than type II tumors (ever vs. never: type I: relative risk (RR) 0.47 [95% confidence interval (CI): 0.33–0.69]; type II, RR: 0.81 [0.61–1.06]). We observed no significant differences in risk in analyses by major histologic subtypes of invasive EOC (serous, mucinous, endometrioid, clear cell). None of the investigated factors were associated with borderline tumors. Established protective factors, including duration of oral contraceptive use and full term pregnancy, were consistently inversely associated with risk across histologic subtypes (e.g., ever full‐term pregnancy: serous, RR: 0.73 [0.58–0.92]; mucinous, RR: 0.53 [0.30–0.95]; endometrioid, RR: 0.65 [0.40–1.06]; clear cell, RR: 0.34 [0.18–0.64]; phet = 0.16). These results suggest limited heterogeneity between reproductive and hormone‐related risk factors and EOC subtypes.


Endocrine-related Cancer | 2014

Early pregnancy sex steroids and maternal risk of epithelial ovarian cancer

Helena Schock; Helja Marja Surcel; Anne Zeleniuch-Jacquotte; Kjell Grankvist; Hans-Åke Lakso; Renée T. Fortner; Rudolf Kaaks; Eero Pukkala; Matti Lehtinen; Paolo Toniolo; Eva Lundin

Well-established associations between reproductive characteristics and epithelial ovarian cancer (EOC) support an involvement of sex steroid hormones in the etiology of EOC. Limited previous studies have evaluated circulating androgens and the risk of EOC, and estrogens and progesterone have been investigated in only one of the previous studies. Furthermore, there is little data on potential heterogeneity in the association between circulating hormones and EOC by histological subgroup. Therefore, we conducted a nested case-control study within the Finnish Maternity Cohort and the Northern Sweden Maternity Cohort to investigate the associations between circulating pre-diagnostic sex steroid concentrations and the histological subtypes of EOC. We identified 1052 EOC cases among cohort members diagnosed after recruitment (1975-2008) and before March 2011. Up to three controls were individually matched to each case (n=2694). Testosterone, androstenedione, 17-hydroxyprogesterone (17-OHP), progesterone, estradiol (E2), and sex hormone-binding globulin levels were measured in serum samples collected during the last pregnancy before EOC diagnosis. We used conditional logistic regression to estimate odds ratios (ORs) and 95% CIs. Associations between hormones and EOC differed with respect to tumor histology and invasiveness. Sex steroid concentrations were not associated with invasive serous tumors; however, doubling of testosterone and 17-OHP concentration was associated with approximately 40% increased risk of borderline serous tumors. A doubling of androgen concentrations was associated with a 50% increased risk of mucinous tumors. The risk of endometrioid tumors increased with higher E2 concentrations (OR: 1.89 (1.20-2.98)). This large prospective study in pregnant women supports a role of sex steroid hormones in the etiology of EOC arising in the ovaries.


Cancer Epidemiology, Biomarkers & Prevention | 2015

Inflammatory Markers and Risk of Epithelial Ovarian Cancer by Tumor Subtypes: The EPIC Cohort

Jennifer Ose; Helena Schock; Anne Tjønneland; Louise Hansen; Kim Overvad; Laure Dossus; Françoise Clavel-Chapelon; Laura Baglietto; Heiner Boeing; Antonia Trichopoulou; Vassiliki Benetou; Pagona Lagiou; Giovanna Masala; Giovanna Tagliabue; Rosario Tumino; Carlotta Sacerdote; Amalia Mattiello; H. Bas Bueno-de-Mesquita; Petra H.M. Peeters; N. Charlotte Onland-Moret; Elisabete Weiderpass; Inger Torhild Gram; Soledad Sánchez; Mireia Obón-Santacana; María-José Sánchez-Pérez; Nerea Larrañaga; José María Huerta Castaño; Eva Ardanaz; Jenny Brändstedt; Eva Lundin

Background: Evidence suggests an etiologic role for inflammation in ovarian carcinogenesis and heterogeneity between tumor subtypes and anthropometric indices. Prospective studies on circulating inflammatory markers and epithelial invasive ovarian cancer (EOC) have predominantly investigated overall risk; data characterizing risk by tumor characteristics (histology, grade, stage, dualistic model of ovarian carcinogenesis) and anthropometric indices are sparse. Methods: We conducted a nested case–control study in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to evaluate C-reactive protein (CRP), IL6, and EOC risk by tumor characteristics. A total of 754 eligible EOC cases were identified; two controls (n = 1,497) were matched per case. We used multivariable conditional logistic regression to assess associations. Results: CRP and IL6 were not associated with overall EOC risk. However, consistent with prior research, CRP >10 versus CRP ≤1 mg/L was associated with higher overall EOC risk [OR, 1.67 (1.03–2.70)]. We did not observe significant associations or heterogeneity in analyses by tumor characteristics. In analyses stratified by waist circumference, inflammatory markers were associated with higher risk among women with higher waist circumference; no association was observed for women with normal waist circumference [e.g., IL6: waist ≤80: ORlog2, 0.97 (0.81–1.16); waist >88: ORlog2, 1.78 (1.28–2.48), Pheterogeneity ≤ 0.01]. Conclusions: Our data suggest that high CRP is associated with increased risk of overall EOC, and that IL6 and CRP may be associated with EOC risk among women with higher adiposity. Impact: Our data add to global evidence that ovarian carcinogenesis may be promoted by an inflammatory milieu. Cancer Epidemiol Biomarkers Prev; 24(6); 951–61. ©2015 AACR.

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Renée T. Fortner

German Cancer Research Center

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Antonia Trichopoulou

National and Kapodistrian University of Athens

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Heiner Boeing

Free University of Berlin

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Rudolf Kaaks

German Cancer Research Center

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