Pieta Krijnen

Leiden University Medical Centre, Leyden, South Holland, Netherlands

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Publications (31)76.99 Total impact

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    ABSTRACT: The aim of this study was to analyze the epidemiology in the bacteriological profile and susceptibility of clinically relevant bacterial pathogens in a burn center in the Netherlands over a 7-year period. The swab results of 693 patients of the period 2005 to 2008 and 539 patients of the period 2009 to 2011 were studied for change of microorganisms and antibiotic resistance. Definitions according to the Working Party on Infection Prevention were used as a tool for assessing the scale of the resistance problem at a local level. Between the studied periods only small changes were found in the bacteriological profile. Staphylococcus aureus showed a slight increase of prevalence in inventory swabs during the second period. In both inventory and wound swabs, S. aureus is the most frequently isolated clinically relevant bacterial pathogen. Resistance for ciprofloxacin in Escherichia coli increased from 3% in 2005 to 2008 to 7% in 2009 to 2011 (P = .028). Resistance for cefotaxim in E. coli increased from 4% in 2005 to 2008 to 14% in 2009 to 2011, although this decrease was not statistically significant (P = .24). The prevalence of highly resistant microorganisms (HRMOs) remained low in both time periods, 4.9% in 2005 to 2008 and 7.4% in 2009 to 2011 (P = .063). The Netherlands is considered a low-prevalence country for antimicrobial resistance, and the occurrence of HRMOs in our center is relatively rare. A large percentage of HRMO isolates were extended spectrum β-lactamase producers, indicating the rapid increase in the production of this resistance mechanism in recent years. The transmission of HRMOs in our center is controlled effectively, using well-established transmission-based precautions.
    Journal of burn care & research: official publication of the American Burn Association 08/2014; · 1.54 Impact Factor
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    ABSTRACT: The evidence for application of silver containing dressings and topicals in the treatment of partial thickness burns in pediatric patients is largely based on clinical trials involving adult patients despite the important differences between the skin of children and adults. A systematic review and meta-analysis was performed of all randomized controlled trials comparing non-silver treatment with silver containing dressings and silver topical agents in children with partial thickness burns in the acute stage. Endpoints were wound healing, grafting, infection, pain, number of dressing changes, length of hospital stay and scarring. Seven randomized controlled trials were included involving 473 participants. All trials used silver sulfadiazine as control in comparison with five different non-silver treatments. Most trials were of moderate quality with high risk of bias. Use of non-silver treatment led to shorter wound healing time (weighted mean difference -3.43 days, 95% confidence interval -4.78, -2.07), less dressing changes (weighted mean difference -19.89 dressing changes, 95% confidence interval -38.12, -.1.66) and shorter length of hospital stay (weighted mean difference -2.07 days, 95% confidence interval -2.63, -1.50) compared to silver sulfadiazine treatment, but no difference in the incidence of wound infection or grafting was found. In conclusion, non-silver treatment may be preferred over silver sulfadiazine but high-quality randomized controlled trials are needed to validly confirm the effectiveness of silver containing preparations, in particular silver containing dressings, above non-silver treatments.
    Wound Repair and Regeneration 06/2014; · 2.76 Impact Factor
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    ABSTRACT: Significance: A high bacterial load interferes with the healing process of a wound. Vacuum-assisted closure (VAC) is a wound healing therapy that utilizes a dressing system that continuously or intermittently applies a negative pressure to the wound surface. Recent Advances: VAC stimulates wound healing, but data on changes in the bacterial load and changes in the bacterial spectrum are scarce. Critical Issues: While VAC supposedly removes bacteria from the treated wounds and therefore reduces the risk of infection, this relationship has not yet been clinically proven. If VAC increases the bacterial load instead of decreasing it, then this may be a reason not to use VAC on certain types of wounds. Only seven small and heterogeneous studies reporting on the relationship between VAC usage and the bacterial load and type of bacteria in the treated wounds in clinical practice were found in the literature. Although there is some low quality evidence that VAC therapy does not change the bacterial load, no definite conclusions on changes in the bacterial load and type of bacteria during VAC can be drawn. Future Directions: Prospectively monitoring changes in the bacterial load and bacterial spectrum in patients that will receive VAC treatment on indication might be an effective way to find out whether it should indeed be used on specific wounds.
    Advances in wound care. 05/2014; 3(5):383-389.
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    ABSTRACT: The choice of treatment for midshaft clavicular fractures is not straightforward, but depends on fracture characteristics such as comminution, angulation and displacement. An online survey was conducted amongst trauma and orthopaedic surgeons to determine the preferred treatment for midshaft clavicular fractures, based on anteroposterior radiographs, for 17 randomly selected displaced or comminuted midshaft clavicular fractures. The background and experience of the respondents were documented. Data were analyzed using a Generalized Estimating Equations (GEE) model. The 102 respondents preferred non-operative treatment more frequently for displaced fractures than for comminuted fractures (OR 3.24, 95% CI 2.55-4.12). Locking plate fixation was more often preferred over other surgical modalities for comminuted than for displaced fractures (OR 1.50, 95% CI 1.17-1.91). In clinical practice, there is no consensus between surgeons on the choice of treatment for displaced or comminuted midshaft clavicular fractures. This lack of agreement calls for evidence-based treatment guidelines for these fractures.
    Acta orthopaedica Belgica 03/2014; 80(1):82-7. · 0.63 Impact Factor
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    ABSTRACT: In the literature no study was found about the effect of localization of burns on outcome. The objective of this retrospective study was to investigate the effect of localization on outcome parameters of 371 patients, admitted to our burn center from January 2009 to December 2011. The patients were included in the study if more than 80% of the burn(s) was localized either on the extremities or on the head and/or trunk. Two groups of TBSA were elaborated, low: 0 to 5% and intermediate: 5 to 15%. Two-hundred ninety-two patients (78.7%) had a low TBSA (<5%) and 79 (21.3%) an intermediate TBSA (5-15%). None of the included patients died. The patients with an intermediate TBSA were on average 8.0 days longer admitted compared with the patients with a low TBSA adjusted for age and depth (95% confidence interval: 6.5-9.4). The patients with burns on the head and/or trunk were more often admitted to the intensive care unit, mostly as a result of suspected inhalation injury (6.2 vs 0.9%; P =.008). More complications were seen in the intermediate TBSA group. In this study no difference in outcome was found between burns on the head and/or trunk or on extremities. The patients with burns on the head and/or trunk group are more frequently admitted to intensive care.
    Journal of burn care & research: official publication of the American Burn Association 02/2014; · 1.54 Impact Factor
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    ABSTRACT: This epidemiological study analyzed the incidence, risk factors, hospital triage and outcome of patients with severe traumatic brain injuries (sTBI) caused by road traffic accidents (RTA) admitted to hospitals in the Trauma Center West-Netherlands (TCWN) region. Trauma registry data were used to identify TBI in all RTA victims admitted to hospitals in the mid-West region of the Netherlands from 2003 to 2011. Type of head injury and severity were classified using the Abbreviated Injury Scale (AIS). Head injuries with AIS severity scores ≥ 3 were considered sTBI. Ten percent of all 12,503 hospital admitted RTA victims sustained sTBI, ranging from 5.4% in motorcyclists, 7.4% in motorists, 9.6% in cyclists and 12.7% in moped riders to 15.1% in pedestrians (p<0.0001). Amongst RTA victims admitted to hospital, sTBI was most prevalent in pedestrians (OR 2.25; 95% CI 1.78-2.86) and moped riders (OR 1.86; 95% CI 1.51-2.30). Injury patterns differed between road user groups. The incidence of contusion ranged from 46.6% in cyclists to 74.2% in motorcyclists, whereas basilar and open skull fractures were least common in motorcyclists (22.6%) and most common in moped riders (51.5%). Haemorrhage incidence ranged from 44.9% (motorists) to 63.6% (pedestrians). Subdural and subarachnoid bleedings were most frequent. Age, Glasgow Coma Scale, and type of haemorrhage were independent prognostic factors for in-hospital mortality after sTBI. In-hospital mortality ranged from 4.2% in moped riders to 14.1% in motorists. Pedestrians have the highest risk to sustain sTBI and more specifically intracranial haemorrhage. Haemorrhage and contusion both occur in over 50% of the patients with sTBI. Specific brain injury patterns can be distinguished for specific road user groups and independent prognostic risk factors for sTBI were identified. This knowledge may be used to improve the vigilance for particular injuries in specific patient groups and stimulate development of focussed diagnostic strategies.
    Journal of neurotrauma 10/2013; · 4.25 Impact Factor
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    ABSTRACT: Background and purpose Type-II distal clavicle fractures according to the Neer classification are generally operated because of the high non-union rate after non-operative treatment. Several surgical techniques have been developed in order to reduce the non-union rate and improve functional outcome. This meta-analysis overviews the available surgical techniques for type-II distal clavicular fractures. Methods We searched the literature systematically. No comparative studies were found. 21 studies (8 prospective and 13 retrospective cohort studies) were selected for the meta-analysis. Data were pooled for 5 surgical outcome measures: function, time to union, time to implant removal, major complications, and minor complications. Results The 21 studies selected included 350 patients with a distal clavicular fracture. Union was achieved in 98% of the patients. Functional outcome was similar between the treatment modalities. Hook-plate fixation was associated with an 11-fold increased risk of major complications compared to intramedullary fixation and a 24-fold increased risk compared to suture anchoring. Interpretation If surgical treatment of a distal clavicle fracture is considered, a fixation procedure with a low risk of complications and a high union rate such as plate fixation or intramedullary fixation should be used. The hook-plate fixation had an increased risk of implant-related complications.
    Acta Orthopaedica 03/2013; · 2.74 Impact Factor
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    ABSTRACT: OBJECTIVE: The debate on whether midshaft clavicular fractures should preferably be treated operatively or nonoperatively still continues. Several patient-related factors may influence this treatment decision. A retrospective study was carried out to determine the relation between fracture type and trauma mechanism, age and sex, and the influence of these factors on the choice of primary treatment. METHODS: Data on the trauma mechanism and treatment of 232 adult patients, who presented with a midshaft clavicular fracture in two hospitals in the Netherlands during the years 2006-2009, were collected. The extent of clavicular shortening, displacement, and fracture type on the primary radiograph were scored. RESULTS: Traffic accidents are the main cause of midshaft clavicular fractures. After correction for age, no relation was found between the trauma mechanism and the fracture type. Older age correlated with more comminuted and displaced fractures. Extensive shortening (>20 mm) was identified as the main clinical indication for primary surgery, whereas displacement and fracture classification seemed less relevant. Operative treatment was increasingly favored from 5% in 2006 to 44% in 2009, which could not be explained by an increase in more complex fractures or by age-related or trauma mechanism-related factors. CONCLUSION: Age has a major influence on the fracture type, whereas the trauma mechanism does not. The choice for the surgical treatment of midshaft clavicular fractures is primarily determined by the amount of axial shortening of the clavicle, rather than by the overall displacement or fracture type. Over the years, the choice of treatment seems to have been increasingly influenced by the patient's and surgeon's preferences.
    European Journal of Emergency Medicine 07/2012; · 0.73 Impact Factor
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    ABSTRACT: While it is suggested that more than 15 lymph nodes (LNs) should be evaluated for accurate staging of gastric cancer, LN yield in western countries is generally low. The effect of preoperative chemotherapy on LN yield in gastric cancer is unknown. The aim of the present study is to determine whether preoperative chemotherapy is associated with any difference in the number of LNs obtained from specimens of patients who underwent curative surgery for gastric adenocarcinoma. In 1205 patients from Memorial Sloan-Kettering Cancer Center (MSKCC) and 1220 patients from the Netherlands Cancer Registry (NCR) who underwent a gastrectomy with curative intent for gastric adenocarcinoma without receiving preoperative radiotherapy, LN yield was analyzed, comparing patients who received preoperative chemotherapy and patients who received no preoperative therapy. Of the 2425 patients who underwent a gastrectomy, 14% received preoperative chemotherapy. Median LN yields were 23 at MSKCC and 10 in the NCR. Despite this twofold difference in LN yield between the two populations, with multivariate Poisson regression, chemotherapy was not associated with LN yield of either population. Variables associated with increased LN yield were institution, female sex, lower age, total (versus distal) gastrectomy and increasing T-stage. In this patient series, treatment at MSKCC, female sex, lower age, total gastrectomy and increasing primary tumor stage were associated with a higher number of evaluated LNs. Preoperative chemotherapy was not associated with a decrease in LN yield. Evaluating more than 15 LNs after gastrectomy is feasible, with or without preoperative chemotherapy.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 04/2012; 38(4):319-25. · 2.56 Impact Factor
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    ABSTRACT: High hospital volume is associated with better outcomes after oesophagectomy and gastrectomy. In the Netherlands, a minimal volume standard of 10 oesophagectomies per year was introduced in 2006. For gastrectomy, no minimal volume standard was set. Aims of this study were to describe changes in hospital volumes, mortality and survival and to explore if high hospital volume is associated with better outcomes after oesophagectomy and gastrectomy in the Netherlands. From 1989 to 2009, 24,246 patients underwent oesophagectomy (N = 10,025) or gastrectomy (N = 14,221) in the Netherlands. Annual hospital volumes were defined as very low (1-5), low (6-10), medium (11-20), and high (≥ 21). Volume-outcome analyses were performed using Cox regression, adjusting for year of diagnosis, case-mix and the use of multi-modality treatment. From 1989 to 2009, the percentage of patients treated in high-volume hospitals increased for oesophagectomy (from 7% to 64%), but decreased for gastrectomy (from 8% to 5%). Six-month mortality (from 15% to 7%) and 3-year survival (from 41% to 52%) improved after oesophagectomy, and to a lesser extent after gastrectomy (6-month mortality: 15%-10%, three-year survival: 55-58%). High hospital volume was associated with lower 6-month mortality (hazard ratio (HR) 0.48, P<0.001) and longer 3-year survival (HR 0.77, P<0.001) after oesophagectomy, but not after gastrectomy. Oesophagectomy was effectively centralised in the Netherlands, improving mortality and survival. Gastrectomies were mainly performed in low volumes, and outcomes after gastrectomy improved to a lesser extent, indicating an urgent need for improvement in quality of surgery and perioperative care for gastric cancer in the Netherlands.
    European journal of cancer (Oxford, England: 1990) 03/2012; 48(7):1004-13. · 4.12 Impact Factor
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    ABSTRACT: From 2006 to 2008, an audit of the multidisciplinary diagnosis and treatment of colorectal cancer patients in the western part of the Netherlands was carried out. We evaluated whether compliance with guidelines had improved. All patients with newly diagnosed and surgically treated colon (n = 1,667) and rectal cancer (n = 544) stage I-III were evaluated. Nine quality indicators were derived from the evidence-based guidelines. In order to compare hospital performances, hospital results were adjusted for casemix differences between hospitals. Colon cancer patients showed an increase in the examination of 10 or more lymph nodes (from 53% to 78%, P < 0.0001). For rectal cancer patients there was an increase in preoperative visualisation of the total colon (63-74%, P = 0.02), MRI (73-85%, P = 0.003), radiotherapy (from 82% to 93% for patients <75 years, P = 0.01) and examination of at least 10 lymph nodes (40-55%, P = 0.004). In 2006, standardised hospital performances differed widely for all quality indicators. Two years later, hospital performances for some quality indicators were more similar. After the feedback of benchmark information, compliance with guidelines for diagnosis and treatment of colorectal cancer patients improved, and differences between individual hospitals decreased. Although secular trends cannot be ruled out, it is highly likely that these results can be attributed to the audit.
    Journal of Surgical Oncology 01/2012; 106(1):1-9. · 2.64 Impact Factor
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    ABSTRACT: In the treatment of femoral shaft fractures in children, the age, the anatomy of the epiphyseal plates, the vascularisation of the femoral head and the length of hospital stay play an important role. The degree in which a malposition after a femoral shaft fracture is corrected by growth depends on the size, the location and the type of dislocation, and on the residual growth potential of the child. In children up to the age of 4, treatment with traction followed by spica casting almost always gives good results. Children up to age 12 are preferably treated with elastic intramedullary nails, if necessary in combination with a spica cast. In special cases, plate osteosynthesis or external fixation can be used. Children older than 12 years are often too heavy for treatment using elastic nails. Because of the still open growth plate of the greater trochanter, the vascularisation of the femoral head and the diameter of the femur, a standard adult intramedullary nail is not always suitable. Recently, a smaller nail for adolescents was developed, which is currently being tested.
    Nederlands tijdschrift voor geneeskunde 01/2012; 156(12):A3976.
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    ABSTRACT: The traditional view that the vast majority of midshaft clavicular fractures heal with good functional outcomes following non-operative treatment may be no longer valid for all midshaft clavicular fractures. Recent studies have presented a relatively high incidence of non-union and identified speciic limitations of the shoulder function in subgroups of patients with these injuries. A prospective, multicentre randomised controlled trial (RCT) will be conducted in 21 hospitals in the Netherlands, comparing fracture consolidation and shoulder function after either non-operative treatment with a sling or a plate fixation. A total of 350 patients will be included, between 18 and 60 years of age, with a dislocated midshaft clavicular fracture. The primary outcome is the incidence of non-union, which will be determined with standardised X-rays (Antero-Posterior and 30 degrees caudocephalad view). Secondary outcome will be the functional outcome, measured using the Constant Score. Strength of the shoulder muscles will be measured with a handheld dynamometer (MicroFET2). Furthermore, the health-related Quality of Life score (ShortForm-36) and the Disabilities of Arm, Shoulder and Hand (DASH) Outcome Measure will be monitored as subjective parameters. Data on complications, bone union, cosmetic aspects and use of painkillers will be collected with follow-up questionnaires. The follow-up time will be two years. All patients will be monitored at regular intervals over the subsequent twelve months (two and six weeks, three months and one year). After two years an interview by telephone and a written survey will be performed to evaluate the two-year functional and mechanical outcomes. All data will be analysed on an intention-to-treat basis, using univariate and multivariate analyses. This trial will provide level-1 evidence for the comparison of consolidation and functional outcome between two standardised treatment options for dislocated midshaft clavicular fractures. The gathered data may support the development of a clinical guideline for treatment of clavicular fractures. Netherlands National Trial Register NTR2399.
    BMC Musculoskeletal Disorders 08/2011; 12:196. · 1.88 Impact Factor
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    ABSTRACT: For several types of cancer, including colon cancer, the survival gap between middle-aged patients and elderly patients widened between 1988 and 1999 in Europe. The aim of our study was to describe treatments and compare survival rates over time (1991-2005) between middle-aged (<65 years), aged (65-74 years) and elderly (≥ 75 years) colon cancer patients in the mid-western part of the Netherlands to assess whether this survival gap further increased. All 8926 patients with invasive colon cancer diagnosed between 1991 and 2005 were selected from the Comprehensive Cancer Centre West. Relative survival was calculated. Relative Excess Risks of death (RER) were estimated using a multivariable generalized linear model with a Poisson distribution. There were no significant changes in the treatment for stage I and II colon. Patients with stage III and IV more often received chemotherapy over time (from 9.6% to 54.3% and from 7.5% to 44.2% for all ages, respectively), while less stage IV patients were operated on (from 73.1% to 55.2%). Relative 5-year survival increased significantly for middle-aged patients (RER = 0.97, 95%CI = 0.95-0.98, p < 0.001), borderline significantly (RER = 0.98, 95%CI = 0.97-0.99, p = 0.05) for elderly patients and not significantly for aged patients (RER = 0.99, 95%CI = 0.97-1.00, p = 0.08) after adjustment for sex, age, grade, stage, and treatment. The survival gap earlier found by the EUROCARE is confirmed for the mid-western part of the Netherlands, even after adjustment for age, sex, grade, stage and treatment. However, present study does not show an increase in the survival gap between middle-aged and elderly patients.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 07/2011; 37(10):904-12. · 2.56 Impact Factor
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    ABSTRACT: About 10% of cutaneous malignant melanomas (CMM) occur in individuals with a family history of melanoma. In 20% to 40% of melanoma families germline mutations in CDKN2A are detected. Knowledge of the clinicohistologic characteristics of melanomas and patients from these families is important for optimization of management strategies, and may shed more light on the complex interplay of genetic and environmental factors in the pathogenesis of melanoma. We sought to investigate the clinical and histologic characteristics of CMM in CDKN2A-mutated families. Clinical and histologic characteristics of 182 patients with 429 CMM from families with a founder mutation in CDKN2A (p16-Leiden mutation) were compared with 7512 patients with 7842 CMM from a population-based cancer registry. Patients with p16-Leiden had their first melanoma 15.3 years younger than control patients. The 5-year cumulative incidence of second primary CMM was 23.4% for patients with p16-Leiden compared with 2.3% for control patients. The risk of a second melanoma was twice as high for patients with p16-Leiden who had their first melanoma before age 40 years, compared with older patients with p16-Leiden. Unlike control patients, there was no body site concordance of the first and second melanoma in patients with p16-Leiden and multiple primary melanomas. Patients with p16-Leiden had significantly more superficial spreading, and less nodular and lentiginous melanomas. Ascertainment of patients with p16-Leiden was family based. The study was performed in families with a founder mutation, the p16-Leiden mutation. Our findings are consistent with a pathogenic pathway of melanoma development from nevi, starting early and ongoing throughout life, and not related to chronic sun exposure.
    Journal of the American Academy of Dermatology 05/2011; 65(2):281-8. · 4.91 Impact Factor
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    ABSTRACT: To gain insight into variations in treatment policy for patients with non-metastatic muscle-invasive bladder carcinoma. Retrospective observational cohort study. A total of 232 patients with non-metastatic muscle-invasive bladder carcinoma in the region of the Comprehensive Cancer Centre the Netherlands, location Leiden in the Netherlands in the period 2003-2005, were examined to ascertain whether treatment guidelines had been adhered to and which factors contributed to variations in policy. Overall and progression-free survival was compared between curative-intent treatment with cystectomy and with radiotherapy. In total 91% of the patients younger than 75 years were treated with curative intent. In patients of 75 years and over, this proportion varied between 77% of those without comorbid disease to 37% of those with more than 1 comorbid conditions. Only 40% of all patients underwent cystectomy as standard treatment. Age was the most important motivation in deciding against surgery. The proportion of patients who underwent cystectomy in the hospitals studied varied between 17% and 54%. In one hospital, this proportion was significantly lower than the regional average. Neoadjuvant chemotherapy was used in only a few hospitals in selected patients. There was no demonstrable difference in overall and progression-free survival between patients who underwent cystectomy and those treated with curative-intent radiotherapy. Age was the deciding factor in the choice of treatment for patients with muscle-invasive bladder carcinoma. The percentage treated by cystectomy varied between hospitals. We recommend thorough documentation of the considerations taken into account when deviating from guidelines.
    Nederlands tijdschrift voor geneeskunde 01/2011; 155:A2703.
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    ABSTRACT: Aim of this study was to describe treatment patterns and outcome according to region, and according to hospital types and volumes among patients with colon cancer in the Netherlands. All patients with invasive colon carcinoma diagnosed in the period 2001-2006 were selected from the Netherlands Cancer Registry. Logistic regression analyses were performed to examine the influence of relevant factors on the odds of having adequate lymph node evaluation, receiving adjuvant chemotherapy and postoperative mortality. Relative survival analysis was used to estimate relative excess risk of dying according to hospital type and volume. In total, 39 907 patients were selected. Patients diagnosed in a university hospital had a higher odds (OR 2.47; 95% CI 2.19-2.78) and patients diagnosed in a hospital with >100 colon carcinoma diagnoses annually had a lower odds (OR 0.70; 95% CI 0.64-0.77) of having >/=10 lymph nodes evaluated. The odds of receiving adjuvant chemotherapy was lower in patients diagnosed in teaching hospitals (OR 0.85; 95% CI 0.73-0.98) and university hospitals (OR 0.56; 95% CI 0.45-0.70) compared to patients diagnosed in non-teaching hospitals. Funnel plots showed large variation in these two outcome measures between individual hospitals. No differences in postoperative mortality were found between hospital types or volumes. Patients diagnosed in university hospitals and patients diagnosed in hospitals with >50 diagnoses of colon carcinoma per year had a better survival. Variation in treatment and outcome of patients with colon cancer in the Netherlands was revealed, with differences between hospital types and volumes. However, variation seemed mainly based on the level of the individual hospital.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 09/2010; 36 Suppl 1:S64-73. · 2.56 Impact Factor
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    ABSTRACT: Aim of this study was to describe treatment patterns and outcome according to region and hospital type and volume among patients with rectal cancer in the Netherlands. All patients with rectal carcinoma diagnosed in the period 2001-2006 were selected from the Netherlands Cancer Registry. Logistic regression analyses were performed to examine the influence of relevant factors on the odds of receiving preoperative radiotherapy and on the odds of postoperative mortality. Relative survival analysis was used to estimate relative excess risk of dying according to hospital type and volume. In total, 16 039 patients were selected. Patients diagnosed in a teaching or university hospital had a lower odds (OR 0.85; 95% CI 0.73-0.99 and OR 0.70; 95% CI 0.52-0.92) and patients diagnosed in a hospital performing >50 resections per year had a higher odds (OR 1.95; 95% CI 1.09-1.76) of receiving preoperative radiotherapy. A large variation between individual hospitals in rates of preoperative radiotherapy and between Comprehensive Cancer Centre-regions in the administration of preoperative chemoradiation was revealed. Postoperative mortality was not correlated to hospital type or volume. Patients with T1-M0 tumours diagnosed in a hospital with >50 resections per year had a better survival compared to patients diagnosed in a hospital with <25 resections per year (RER 0.11; 95% CI 0.02-0.78). This study demonstrated variation in treatment and outcome of patients with rectal cancer in the Netherlands, with differences related to hospital volume and hospitals teaching or academic status. However, variation in treatment patterns between individual hospitals proved to be much larger than could be explained by the investigated characteristics. Future studies should focus on the reasons behind these differences, which could lead to a higher proportion of patients receiving optimal treatment for their stage of the disease.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 09/2010; 36 Suppl 1:S74-82. · 2.56 Impact Factor
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    ABSTRACT: We described changes in treatment of colon cancer over time and the impact on survival in The Netherlands in the period 1989-2006. All 103,744 patients with invasive colon cancer during 1989-2006 in The Netherlands were included. Data were extracted from The Netherlands Cancer Registry. Trends in treatment over time were analysed and multivariable relative survival analysis was carried out. The administration of adjuvant chemotherapy in stage III patients <75 years increased from 19% in 1989-1993 to 79% in 2004-2006 and from 1% to 19% in stage III patients ≥75 years. Among stage IV patients, resection rates of the primary tumour decreased from 72% to 63%, while chemotherapy administration increased from 23% to 64% in those <75 years. Survival increased from 52% to 58% in males and from 55% to 58% among females. Stage III patients with adjuvant chemotherapy exhibited a relative excess risk of 0.4 (95% confidence interval 0.4-0.4) compared with those without. Among stage IV patients, resection of primary tumour, palliative chemotherapy, and metastasectomy were important prognostic factors. There were substantial improvements in management and survival of colon cancer from 1989 to 2006. Stage III disease patients with colon cancer experienced the largest improvement in survival, most likely related to the increased administration of adjuvant chemotherapy.
    Annals of Oncology 05/2010; 21(11):2206-12. · 7.38 Impact Factor
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    ABSTRACT: Since the 1990s, treatment of patients with rectal cancer has changed in the Netherlands. Aim of this study was to describe these changes in treatment over time and to evaluate their effects on survival. All patients in the Netherlands Cancer Registry with invasive primary rectal cancer diagnosed during the period 1989-2006 were selected. The Cochran-Armitage trend test was used to analyse trends in treatment over time. Multivariate relative survival analyses were performed to estimate relative excess risk (RER) of dying. In total, 40,888 patients were diagnosed with rectal cancer during the period 1989-2006. The proportion of patients with stages II and III disease receiving preoperative radiotherapy increased from 1% in the period 1989-1992 to 68% in the period 2004-2006 for younger patients (<75 years) and from 1% to 51% for older patients (>or=75 years), whereas the use of postoperative radiotherapy decreased. Administration of chemotherapy to patients with stage IV disease increased over time from 21% to 66% for patients younger than 75 years. Both males and females exhibited an increase in five-year relative survival from 53% to 60%. The highest increase in survival was found for patients with stage III disease. In the multivariate analyses survival improved over time for patients with stages II-IV disease. After adjustment for treatment variables, this improvement remained significant for patients with stages III and IV disease. The changes in therapy for rectal cancer have led to a markedly increased survival. Patients with stage III disease experienced the greatest improvement in survival.
    European journal of cancer (Oxford, England: 1990) 02/2010; 46(8):1421-9. · 4.12 Impact Factor

Publication Stats

317 Citations
76.99 Total Impact Points

Institutions

  • 2009–2014
    • Leiden University Medical Centre
      • Department of Surgery
      Leyden, South Holland, Netherlands
  • 2011
    • Integraal Kankercentrum Nederland
      Amsterdamo, North Holland, Netherlands
  • 2007–2009
    • Netherlands Cancer Institute
      Amsterdamo, North Holland, Netherlands
  • 2006
    • Erasmus MC
      • Department of Public Health
      Rotterdam, South Holland, Netherlands
  • 2005
    • Erasmus Universiteit Rotterdam
      Rotterdam, South Holland, Netherlands