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Dive into the research topics where Jan C. Oosterwijk is active.

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Featured researches published by Jan C. Oosterwijk.


The Lancet | 1999

Signs and symptoms of Duchenne muscular dystrophy and Becker muscular dystrophy among carriers in The Netherlands: a cohort study

Edo M. Hoogerwaard; Erin Bakker; P.F. Ippel; Jan C. Oosterwijk; D F Majoor-Krakauer; N.J. Leschot; A.J. van Essen; Han G. Brunner; P. A. Van Der Wouw; Arthur A.M. Wilde; M. de Visser

BACKGROUND Carriers of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) may show muscle weakness or dilated cardiomyopathy. Studies focusing on skeletal-muscle involvement were done before DNA analysis was possible. We undertook a cross-sectional study in a population of definite carriers to estimate the proportion and to assess the clinical profile of carriers with symptoms. We also assessed a possible correlation between genotype and phenotype. METHODS Carriers of DMD and BMD, aged 18-60 years, were traced through the files of the central register kept at the Department of Human Genetics in Leiden, Netherlands. For each carrier who agreed to participate a medical history was taken, and muscle-strength assessment by hand-held dynamometry and manual muscle testing and cardiological assessment were done. FINDINGS 129 carriers of muscular dystrophy (85 DMD, 44 BMD) participated in the study. In 90 women from 52 (70%) families, 37 different mutations were found. 28 (22%) women had symptoms. 22 (17%) had muscle weakness, varying from mild to moderately severe. Muscle weakness was found in carriers of DMD and BMD, but dilated cardiomyopathy was found only in seven (8%) carriers of DMD, of whom one had concomitant muscle weakness. There was an unexpectedly high proportion of left-ventricle dilation (18%). No genotype-phenotype correlation was found. INTERPRETATION Clinical manifestation of muscle weakness, dilated cardiomyopathy, or both can be found in about a fifth of carriers of DMD and BMD. If left-ventricle dilation is taken into account, the proportion of carriers with symptoms is even higher, amounting to 40%.


Journal of Clinical Oncology | 2010

BRCA1-Associated Breast Cancers Present Differently From BRCA2-Associated and Familial Cases: Long-Term Follow-Up of the Dutch MRISC Screening Study

A.J. Rijnsburger; Inge-Marie Obdeijn; R. Kaas; Madeleine M. A. Tilanus-Linthorst; Carla Boetes; Claudette E. Loo; Martin N. J. M. Wasser; Elisabeth Bergers; Theo Kok; Sara H. Muller; Hans Peterse; Rob A. E. M. Tollenaar; Nicoline Hoogerbrugge; Sybren Meijer; C.C.M. Bartels; Caroline Seynaeve; Maartje J. Hooning; Mieke Kriege; P.I.M. Schmitz; Jan C. Oosterwijk; Harry J. de Koning; Emiel J. Th. Rutgers; J.G.M. Klijn

PURPOSE The Dutch MRI Screening Study on early detection of hereditary breast cancer started in 1999. We evaluated the long-term results including separate analyses of BRCA1 and BRCA2 mutation carriers and first results on survival. PATIENTS AND METHODS Women with higher than 15% cumulative lifetime risk (CLTR) of breast cancer were screened with biannual clinical breast examination and annual mammography and magnetic resonance imaging (MRI). Participants were divided into subgroups: carriers of a gene mutation (50% to 85% CLTR) and two familial groups with high (30% to 50% CLTR) or moderate risk (15% to 30% CLTR). RESULTS Our update contains 2,157 eligible women including 599 mutation carriers (median follow-up of 4.9 years from entry) with 97 primary breast cancers detected (median follow-up of 5.0 years from diagnosis). MRI sensitivity was superior to that of mammography for invasive cancer (77.4% v 35.5%; P<.00005), but not for ductal carcinoma in situ. Results in the BRCA1 group were worse compared to the BRCA2, the high-, and the moderate-risk groups, respectively, for mammography sensitivity (25.0% v 61.5%, 45.5%, 46.7%), tumor size at diagnosis≤1 cm (21.4% v 61.5%, 40.9%, 63.6%), proportion of DCIS (6.5% v 18.8%, 14.8%, 31.3%) and interval cancers (32.3% v 6.3%, 3.7%, 6.3%), and age at diagnosis younger than 30 years (9.7% v 0%). Cumulative distant metastasis-free and overall survival at 6 years in all 42 BRCA1/2 mutation carriers with invasive breast cancer were 83.9% (95% CI, 64.1% to 93.3%) and 92.7% (95% CI, 79.0% to 97.6%), respectively, and 100% in the familial groups (n=43). CONCLUSION Screening results were somewhat worse in BRCA1 mutation carriers, but 6-year survival was high in all risk groups.


American Journal of Medical Genetics Part A | 2004

Inheritance of most X-linked traits is not dominant or recessive, just X-linked

William B. Dobyns; Allison Filauro; Brett N. Tomson; April S. Chan; Allen W. Ho; Nicholas T. Ting; Jan C. Oosterwijk; Carole Ober

The existence of X‐linked disorders in humans has been recognized for many centuries, based on lessons in religious texts and observations of specific human families (e.g., color blindness or Daltonism). Our modern concepts of Mendelian (including X‐linked) inheritance originated just after the turn of the last century. Early concepts of dominance and recessiveness were first used in conjunction with autosomal traits, and then applied to “sex”‐linked traits to distinguish X‐linked recessive and X‐linked dominant inheritance. The former was defined as vertical transmission in which carrier women pass the disorder to affected sons, while the latter was defined as vertical transmission in which daughters of affected males are always affected, transmitting the disorder to offspring of both sexes. However, many X‐linked disorders such as adrenoleukodystrophy, fragile X syndrome, and ornithine transcarbamylase deficiency do not fit these rules. We reviewed the literature on 32 X‐linked disorders and recorded information on penetrance and expressivity in both sexes. As expected, penetrance and an index of severity of the phenotype (defined in our Methods) were both high in males, while the severity index was low in females. Contrary to standard presentations of X‐linked inheritance, penetrance was highly variable in females. Our analysis classified penetrance as high in 28% of the disorders studied, intermediate in 31%, and low in 40%. The high proportion of X‐linked disorders with intermediate penetrance is difficult to reconcile with standard definitions of X‐linked recessive and dominant inheritance. They do not capture the extraordinarily variable expressivity of X‐linked disorders or take into account the multiple mechanisms that can result in disease expression in females, which include cell autonomous expression, skewed X‐inactivation, clonal expansion, and somatic mosaicism. We recommend that use of the terms X‐linked recessive and dominant be discontinued, and that all such disorders be simply described as following “X‐linked” inheritance.


International Journal of Cancer | 2009

Time to stop ovarian cancer screening in BRCA1/2 mutation carriers?

Nienke M. van der Velde; Marian J.E. Mourits; Henriette J.G. Arts; Jacob de Vries; Beike K. Leegte; Grieteke Dijkhuis; Jan C. Oosterwijk; Geertruida H. de Bock

Women at high risk of ovarian cancer due to a genetic predisposition may opt for either surveillance or prophylactic bilateral salpingo‐oophorectomy (pBSO). Main objective of our study was to determine the effectiveness of ovarian cancer screening in women with a BRCA1/2 mutation. We evaluated 241 consecutive women with a BRCA1 or BRCA2 mutation who were enrolled in the surveillance program for hereditary ovarian cancer from September 1995 until May 2006 at the University Medical Center Groningen (UMCG), The Netherlands. The ovarian cancer screening included annual pelvic examination, transvaginal ultrasound (TVU) and serum CA125 measurement. To evaluate the effectiveness of screening in diagnosing (early stage) ovarian cancer sensitivity, specificity, positive and negative predictive values (PPV and NPV) of pelvic examination, TVU and CA125 were calculated. Three ovarian cancers were detected during the surveillance period; 1 prevalent cancer, 1 interval cancer and 1 screen‐detected cancer, all in an advanced stage (FIGO stage IIIc). A PPV of 20% was achieved for pelvic examination, 33% for TVU and 6% for CA125 estimation alone. The NPV were 99.4% for pelvic examination, 99.5% for TVU and 99.4% for CA125. All detected ovarian cancers were in an advanced stage, and sensitivities and positive predictive values of the screening modalities are low. Restricting the analyses to incident contacts that contained all 3 screening modalities did not substantially change the outcomes. Annual gynecological screening of women with a BRCA1/2 mutation to prevent advanced stage ovarian cancer is not effective.


Journal of Clinical Oncology | 2004

Randomized Trial of a Shared Decision-Making Intervention Consisting of Trade-Offs and Individualized Treatment Information for BRCA1/2 Mutation Carriers

M.S. van Roosmalen; Peep F. M. Stalmeier; Lia C.G. Verhoef; Josette E. H. M. Hoekstra-Weebers; Jan C. Oosterwijk; Nicoline Hoogerbrugge; U. Moog; W.A.J. van Daal

PURPOSE To evaluate a shared decision-making intervention (SDMI) for BRCA1/2 mutation carriers who have to make a choice between screening and prophylactic surgery for breasts and/or ovaries. PATIENTS AND METHODS The SDMI consisted of two value assessment sessions, using the time trade-off method, followed by individualized treatment information based on (quality-adjusted) life expectancy. After the baseline assessment (2 weeks after a positive DNA test result), women were randomly assigned to the SDMI group (n = 44), receiving the SDMI 2 months after the test result, or to the control group (n = 44). The short- and long-term effects, 3 and 9 months after the test result, were assessed using questionnaires. Data were collected on well-being, treatment choice, and decision-related outcomes. RESULTS In the short term, the SDMI had no effect. In the long term, with respect to well-being, patients in the SDMI group had less intrusive thoughts (P =.05) and better general health (P =.01) and tended to be less depressed (P =.07). With respect to decision-related outcomes for the breasts, the SDMI group held stronger preferences (P =.02) and agreed more strongly to having weighed the pros and cons (P =.01). No effect was found on treatment choice. In the long term, interaction effects between the SDMI and cancer history were found. The SDMI showed an overall beneficial effect for unaffected women, whereas affected women tended to experience detrimental effects. CONCLUSION We conclude that the SDMI improved decision making in unaffected BRCA1/2 mutation carriers. Supporting decision making in a systematic way using trade-offs is beneficial for these women.


European Journal of Cancer | 2013

Support of the ‘fallopian tube hypothesis’ in a prospective series of risk-reducing salpingo-oophorectomy specimens

Welmoed Reitsma; Geertruida H. de Bock; Jan C. Oosterwijk; Joost Bart; Harry Hollema; Marian J.E. Mourits

OBJECTIVE To determine the prevalence, localisation and type of occult (non)invasive cancer in risk-reducing salpingo-oophorectomy (RRSO) specimens in BRCA-mutation carriers and high-risk women from BRCA-negative families. METHODS A consecutive series of RRSO specimens of asymptomatic, screen-negative high-risk women were prospectively collected in our tertiary multidisciplinary cancer clinic from January 2000 until March 2012. All high-risk women in this study underwent genetic testing on BRCA-mutations. The surgico-pathological protocol comprised complete resection of ovaries and fallopian tubes, transverse sectioning at 2-3 mm (sectioning and extensively examining the fimbrial end [SEE-FIM] protocol from 2006) and double independent pathology review of morphologically deviant sections. RESULTS Three hundred and sixty RRSOs were performed in 188 BRCA1-carriers, 115 BRCA2-carriers and 57 BRCA-negative women at a median age of 44.0 years. Four occult invasive cancers were detected in BRCA-carriers (1.3%, 95%-confidence interval (CI) 0.03-2.61), all in BRCA1-carriers >40 years of age. All cancers, of which two tubal and two ovarian cancers, were FIGO-stage I/II. Three non-invasive serous intraepithelial carcinomas (STICs) were detected in BRCA-carriers (1.0%, 95%-CI 0.00-2.10). In BRCA-negative women one STIC was found (1.8%, 95%-CI 0.00-5.16), however she carried an unclassified variant in BRCA2. Total follow-up after RRSO was 1691 woman-years, in which one BRCA1-carrier developed peritoneal cancer (0.3%, 95%-CI 0.00-0.82). CONCLUSIONS A low prevalence of occult invasive cancer (1.1%) was found in young asymptomatic, screen-negative women at increased ovarian cancer risk undergoing RRSO. This study adds to the advice to perform RRSO in BRCA1-carriers before the age of 40. Our findings support the hypothesis of the fallopian tube as the primary site of origin of pelvic high-grade serous cancer.


American Journal of Medical Genetics Part A | 2004

Impact of BRCA1/2 testing and disclosure of a positive test result on women affected and unaffected with breast or ovarian cancer

Mariëlle S. van Roosmalen; Peep F. M. Stalmeier; Lia C.G. Verhoef; Josette E. H. M. Hoekstra-Weebers; Jan C. Oosterwijk; Nicoline Hoogerbrugge; U. Moog; W.A.J. van Daal

To evaluate the impact of BRCA1/2 testing and disclosure of a positive test result on women affected and unaffected with cancer. Longitudinal cohort study including women affected and unaffected with breast or ovarian cancer testing for a BRCA1/2 mutation. Data on well‐being (anxiety, depression, cancer related distress, general health), treatment choice, and decision making about cancer prevention were collected at baseline (1 week after blood sampling; affected n = 192, unaffected n = 176) and at follow‐up (2 weeks after disclosure of a positive test result; affected n = 23, unaffected n = 66). Women affected and unaffected with breast or ovarian cancer were compared using univariate statistics. Change over time was examined using repeated measures analysis of variance. With respect to well‐being, affected women scored worse at baseline. At follow‐up, both affected and unaffected women experienced a decline in well‐being, which tended to be stronger in affected women. Women diagnosed with cancer less than 1 year previously tended to report a worse well‐being than those diagnosed longer ago. With respect to treatment choice, more affected women intended to obtain prophylactic surgery and valued it higher at both time points. With respect to decision making, affected women had a lower preference for participation in decision making at baseline; no differences were found at follow‐up. At follow‐up, both affected and unaffected women showed an increase in strength of treatment preference and a decrease in decision uncertainty. Disclosure of a positive test result had a negative impact on well‐being. Affected women, especially those who have been recently diagnosed with cancer, experienced the worst well‐being and could benefit from psychosocial support.


British Journal of Cancer | 2004

Randomised trial of a decision aid and its timing for women being tested for a BRCA1/2 mutation

M.S. van Roosmalen; Peep F. M. Stalmeier; Lia C.G. Verhoef; Josette E. H. M. Hoekstra-Weebers; Jan C. Oosterwijk; Nicoline Hoogerbrugge; U. Moog; W.A.J. van Daal

The aim of the study was to evaluate the impact of a decision aid (DA) and its timing in women being tested for a BRCA1/2 mutation. Women with and without a previous history of cancer were included after blood sampling for genetic testing. The DA consisted of a brochure and video providing information on screening and prophylactic surgery. To evaluate the impact of the DA, women were randomised to the DA group (n=184), receiving the DA 2 weeks after blood sampling, or to the control group (n=184). To evaluate the impact of timing, mutation carriers who had received the DA before the test result (n=47) were compared to mutation carriers who received the DA after the test result (n=42). Data were collected on well-being, treatment choice, decision and information related outcomes. The impact of the DA was measured 4 weeks after blood sampling. The impact of timing was measured 2 weeks after a positive test result. The DA had no impact on well-being. Regarding decision related outcomes, the DA group more frequently considered prophylactic surgery (P=0.02) corroborated with higher valuations (P=0.04). No differences were found for the other decision related outcomes. Regarding information related outcomes, the DA group felt better informed (P=0.00), was more satisfied with the information (P=0.00), and showed more accurate risk perceptions. Timing of the DA had no effect on any of the outcomes. No interactions were found between the DA and history of cancer. In conclusion, women being tested for a BRCA1/2 mutation benefit from the DA on information related outcomes. Because timing had no effect, the DA is considered useful either before or after the test result.


Cancer Epidemiology, Biomarkers & Prevention | 2012

Differences in Natural History between Breast Cancers in BRCA1 and BRCA2 Mutation Carriers and Effects of MRI Screening-MRISC, MARIBS, and Canadian Studies Combined

Eveline A.M. Heijnsdijk; Ellen Warner; Fiona J. Gilbert; Madeleine M.A. Tilanus-Linthorst; D. Gareth Evans; Petrina Causer; Rosalind Eeles; Reinie Kaas; Gerrit Draisma; Elizabeth Ramsay; Ruth Warren; Kimberley Hill; Nicoline Hoogerbrugge; Martin N. J. M. Wasser; Elisabeth Bergers; Jan C. Oosterwijk; Maartje J. Hooning; Emiel J. Th. Rutgers; J.G.M. Klijn; Don B. Plewes; Martin O. Leach; Harry J. de Koning

Background: It is recommended that BRCA1/2 mutation carriers undergo breast cancer screening using MRI because of their very high cancer risk and the high sensitivity of MRI in detecting invasive cancers. Clinical observations suggest important differences in the natural history between breast cancers due to mutations in BRCA1 and BRCA2, potentially requiring different screening guidelines. Methods: Three studies of mutation carriers using annual MRI and mammography were analyzed. Separate natural history models for BRCA1 and BRCA2 were calibrated to the results of these studies and used to predict the impact of various screening protocols on detection characteristics and mortality. Results: BRCA1/2 mutation carriers (N = 1,275) participated in the studies and 124 cancers (99 invasive) were diagnosed. Cancers detected in BRCA2 mutation carriers were smaller [80% ductal carcinoma in situ (DCIS) or ≤10 mm vs. 49% for BRCA1, P < 0.001]. Below the age of 40, one (invasive) cancer of the 25 screen-detected cancers in BRCA1 mutation carriers was detected by mammography alone, compared with seven (three invasive) of 11 screen-detected cancers in BRCA2 (P < 0.0001). In the model, the preclinical period during which cancer is screen-detectable was 1 to 4 years for BRCA1 and 2 to 7 years for BRCA2. The model predicted breast cancer mortality reductions of 42% to 47% for mammography, 48% to 61% for MRI, and 50% to 62% for combined screening. Conclusions: Our studies suggest substantial mortality benefits in using MRI to screen BRCA1/2 mutation carriers aged 25 to 60 years but show important clinical differences in natural history. Impact: BRCA1 and BRCA2 mutation carriers may benefit from different screening protocols, for example, below the age of 40. Cancer Epidemiol Biomarkers Prev; 21(9); 1458–68. ©2012 AACR.


Journal of Medical Genetics | 2014

Breast and ovarian cancer risks in a large series of clinically ascertained families with a high proportion of BRCA1 and BRCA2 Dutch founder mutations

Richard Brohet; Maria E. Velthuizen; Frans B. L. Hogervorst; Hanne Meijers-Heijboer; Caroline Seynaeve; Margriet J. Collee; Senno Verhoef; Margreet G. E. M. Ausems; Nicoline Hoogerbrugge; Christi J. van Asperen; Encarna Gomez Garcia; Fred H. Menko; Jan C. Oosterwijk; Peter Devilee; Laura van 't Veer; Flora E. van Leeuwen; Douglas F. Easton; Matti A. Rookus; Antonis C. Antoniou; Hebon Resource

Background BRCA1 or BRCA2 mutations confer increased risks of breast and ovarian cancer, but risks have been found to vary across studies and populations. Methods We ascertained pedigree data of 582 BRCA1 and 176 BRCA2 families and studied the variation in breast and ovarian cancer risks using a modified segregation analysis model. Results The average cumulative breast cancer risk by age 70 years was estimated to be 45% (95% CI 36 to 52%) for BRCA1 and 27% (95% CI 14 to 38%) for BRCA2 mutation carriers. The corresponding cumulative risks for ovarian cancer were 31% (95% CI 17 to 43%) for BRCA1 and 6% (95% CI 2 to 11%) for BRCA2 mutation carriers. In BRCA1 families, breast cancer relative risk (RR) increased with more recent birth cohort (pheterogeneity = 0.0006) and stronger family histories of breast cancer (pheterogeneity<0.001). For BRCA1, our data suggest a significant association between the location of the mutation and the ratio of breast to ovarian cancer (p<0.001). By contrast, in BRCA2 families, no evidence was found for risk heterogeneity by birth cohort, family history or mutation location. Conclusions BRCA1 mutation carriers conferred lower overall breast and ovarian cancer risks than reported so far, while the estimates of BRCA2 mutations were among the lowest. The low estimates for BRCA1 might be due to older birth cohorts, a moderate family history, or founder mutations located within specific regions of the gene. These results are important for a more accurate counselling of BRCA1/2 mutation carriers.

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Marian J.E. Mourits

University Medical Center Groningen

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Geertruida H. de Bock

University Medical Center Groningen

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Christi J. van Asperen

Loyola University Medical Center

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Liesbeth Jansen

University Medical Center Groningen

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Fred H. Menko

Netherlands Cancer Institute

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Maartje J. Hooning

Erasmus University Rotterdam

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J.G.M. Klijn

Erasmus University Rotterdam

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