Johan L Dikken

Memorial Sloan-Kettering Cancer Center, New York City, New York, United States

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Publications (25)101.08 Total impact

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    ABSTRACT: The internationally validated Memorial Sloan-Kettering Cancer Center (MSKCC) gastric carcinoma nomogram was based on patients who underwent curative (R0) gastrectomy, without any other therapy. The purpose of the current study was to assess the performance of this gastric cancer nomogram in patients who received chemoradiation therapy after an R0 resection for gastric cancer. In a combined dataset of 76 patients from the Netherlands Cancer Institute (NKI), and 63 patients from MSKCC, who received postoperative chemoradiation therapy (CRT) after an R0 gastrectomy, the nomogram was validated by means of the concordance index (CI) and a calibration plot. The concordance index for the nomogram was 0.64, which was lower than the CI of the nomogram for patients who received no adjuvant therapy (0.80). In the calibration plot, observed survival was approximately 20% higher than the nomogram-predicted survival for patients receiving postoperative CRT. The MSKCC gastric carcinoma nomogram significantly underpredicted survival for patients in the current study, suggesting an impact of postoperative CRT on survival in patients who underwent an R0 resection for gastric cancer, which has been demonstrated by randomized controlled trials. This analysis stresses the need for updating nomograms with the incorporation of multimodal strategies.
    International journal of radiation oncology, biology, physics 01/2014; · 4.59 Impact Factor
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    ABSTRACT: BACKGROUND: This study was designed to define a statistically sound and clinically meaningful cutoff point for annual hospital volume for esophagectomy. Higher hospital volumes are associated with improved outcomes after esophagectomy. However, reported optimal volumes in literature vary, and minimal volume standards in different countries show considerable variation. So far, there has been no research on the noncategorical, nonlinear, volume-outcome relationship in esophagectomy. METHODS: Data were derived from the Netherlands Cancer Registry. Restricted cubic splines were used to investigate the nonlinear effects of annual hospital volume on 6 month and 2 year mortality rates. Outcomes were adjusted for year of diagnosis, case-mix, and (neo)adjuvant treatment. RESULTS: Between 1989 and 2009, 10,025 patients underwent esophagectomy for cancer in the Netherlands. Annual hospital volumes varied between 1 and 83 year, increasing over time. Increasing annual hospital volume showed a continuous, nonlinear decrease in hazard ratio (HR) for mortality along the curve. Increasing hospital volume from 20 year (baseline, HR = 1.00) to 40 and 60 year was associated with decreasing 6 month mortality, with a HR of 0.73 (95 % confidence interval (0.65-0.83) and 0.67 (0.58-0.77) respectively. Beyond 60 year, no further decrease was detected. Higher hospital volume also was associated with decreasing 2 year mortality until 50 esophagectomies year with a HR of 0.86 (0.79-0.93). CONCLUSIONS: Centralization of esophagectomy to a minimum of 20 resections/year has been effectively introduced in the Netherlands. Increasing annual hospital volume was associated with a nonlinear decrease in mortality up to 40-60 esophagectomies/year, after which a plateau was reached. This finding may guide quality improvement efforts worldwide.
    Ann Surg Oncol. 01/2014;
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    ABSTRACT: Studies investigating perioperative chemotherapy and/or radiotherapy changed the treatment of curable gastric cancer in The Netherlands. These changes were evaluated including their influence on survival. Data on patients diagnosed with gastric cancer from 1989 to 2009 were obtained from The Netherlands Cancer Registry. Changes over time in surgery and administration of perioperative chemotherapy, 30-day mortality, 5-year survival and adjusted relative excess risk (RER) of dying were analyzed with multivariable regression for cardia and noncardia cancer. In stages I and II disease, most patients underwent surgery. Since 2005, more patients are treated with (neo)adjuvant chemotherapy. Postoperative mortality ranged from 1% to 7% and 0.4% to 12.2% in cardia and noncardia cancer (<55 to 75+ years). Five-year survival for cardia cancer and noncardia cancer stages I–III and X (unknown stage) was 33% and 50% (2005–2008). The RER of dying was associated with period of diagnosis, age, gender, region, stage, (neo)adjuvant chemotherapy in case of cardia cancer and type of gastric resection in case of noncardia cancer. Administration of (neo)adjuvant chemotherapy has increased. No improvement in long-term survival could yet be seen, though it is still too early to expect an improvement in survival as a result of the use of chemotherapy.
    International Journal of Cancer 10/2013; 133(8). · 6.20 Impact Factor
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    ABSTRACT: Background. Gastric cardia and non-cardia cancer exhibit differences in biological and epidemiological features across the world. The aims of this study were to analyze trends in incidence, stage distribution, and survival over a 20-year period in the Netherlands, separately for both types of gastric cancer. Methods. Data on all patients with a diagnosis of gastric cancer in the period 1989-2008 were obtained from the nationwide Netherlands Cancer Registry. Time trends in incidence [analyzed as European Standard Rate per 100 000 (ESR)] and relative survival were separately analyzed for cardia and non-cardia gastric cancer. Results. A total of 47 295 patients were included. Incidence rates per 100 000 for cardia cancer declined from 5.7 to 4.3 for males and remained stable for females (1.2). For non-cardia cancer, the incidence in males declined from 25 to 14 and in females from 10 to 7. Proportional incidence in stage IV cardia and non-cardia cancer increased in 2004-2008 (cardia 32-42%, non-cardia 33-45%). Five-year survival rates for stage I-III and X (unknown) remained stable (cardia cancer: 20%, non-cardia gastric cancer: 31%). Five-year survival for stage IV disease was 1.9% and 1.0% for cardia and non-cardia gastric cancer. Conclusion. The incidence of gastric cancer in the Netherlands markedly decreased over the past decades, in particular of non-cardia cancer. Survival remained dismal. Improvement of survival remains a challenge for the multidisciplinary team involved in gastric cancer treatment.
    Acta oncologica (Stockholm, Sweden) 07/2013; · 2.27 Impact Factor
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    ABSTRACT: The extent of surgery for gastric cancer has been debated since Billroth performed his first gastrectomy in 1881. This review gives an overview of the available literature on the extent of gastrectomy and lymphadenectomy for advanced resectable gastric cancer. Subtotal gastrectomy is associated with lower morbidity and mortality compared with total gastrectomy, without compromising long-term survival. However, a positive resection margin decreases the chance of curation. Frozen section examination may prevent this. For poorly differentiated singlet ring cell tumors, there may be an argument to perform a total gastrectomy in all cases. In 1981, the Japanese Research Society for the Study of Gastric Cancer provided guidelines for the standardization of surgical treatment and pathological evaluation of gastric cancer. Since then, D2 lymph node dissections have become the standard of care in Japan. Because of the superior stage-specific survival rates in Japan, a D2 dissection was evaluated in several Western randomized controlled trials, but no survival benefit was found for a D2 over a D1 dissection. This might be explained by the increased mortality in the D2 dissection groups which might be the result of a standard pancreaticosplenectomy and low experience with D2 dissections. Adding the removal of the para-aortic nodes to a D2 dissection does not further improve survival. The removal of lymph node stations 10 and 11 by splenectomy showed an increased morbidity, no survival benefit, and a very poor prognosis if lymph nodes were affected. Therefore, pancreaticosplenectomy should only be performed in cases of tumor invasion into these organs. A D2 dissection without routine splenectomy and pancreatic tail resection in experienced hands should be considered standard of care for advanced resectable gastric cancer, both in Asian and in Western patients. Centralization and auditing may further improve outcomes after gastrectomy.
    Digestive surgery 01/2013; 30(2):96-103. · 1.37 Impact Factor
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    ABSTRACT: Aims Seven countries (Denmark, France, Ireland, the Netherlands, Poland, Sweden, United Kingdom) collaborated to initiate a EURECCA (European Registration of Cancer Care) Upper GI project. The aim of this study was to identify a core dataset of shared items in the different data registries which can be used for future collaboration between countries. Methods Itemlists from all participating Upper GI cancer registries were collected. Items were scored ‘present’ when included in the registry, or when the items could be deducted from other items in the registry. The definition of a common item was that it was present in at least six of the seven participating countries. Results The number of registered items varied between 40 (Poland) and 650 (Ireland). Among the 46 shared items were data on patient characteristics, staging and diagnostics, neo-adjuvant treatment, surgery, postoperative course, pathology, and adjuvant treatment. Information on non-surgical treatment was available in only 4 registries. Conclusions A list of 46 shared items from seven participating Upper GI cancer registries was created, providing a basis for future quality assurance and research in Upper GI cancer treatment on a European level.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 01/2013; · 2.56 Impact Factor
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    ABSTRACT: BACKGROUND: In several European countries, centralization of oesophagogastric cancer surgery has been realized and clinical audits initiated. The present study was designed to evaluate differences in resection rates, outcomes and annual hospital volumes between these countries, and to analyse the relationship between hospital volume and outcomes. METHODS: National data were obtained from cancer registries or clinical audits in the Netherlands, Sweden, Denmark and England. Differences in outcomes were analysed between countries and between hospital volume categories, adjusting for available case-mix factors. RESULTS: Between 2004 and 2009, 10 854 oesophagectomies and 9010 gastrectomies were registered. Resection rates in England were 18·2 and 21·6 per cent for oesophageal and gastric cancer respectively, compared with 28·5-29·9 and 41·4-41·9 per cent in the Netherlands and Denmark (P < 0·001). The adjusted 30-day mortality rate after oesophagectomy was lowest in Sweden (1·9 per cent). After gastrectomy, the adjusted 30-day mortality rate was significantly higher in the Netherlands (6·9 per cent) than in Sweden (3·5 per cent; P = 0·017) and Denmark (4·3 per cent; P = 0·029). Increasing hospital volume was associated with a lower 30-day mortality rate after oesophagectomy (odds ratio 0·55 (95 per cent confidence interval 0·42 to 0·72) for at least 41 versus 1-10 procedures per year) and gastrectomy (odds ratio 0·64 (0·41 to 0·99) for at least 21 versus 1-10 procedures per year). CONCLUSION: Hospitals performing larger numbers of oesophagogastric cancer resections had a lower 30-day mortality rate. Differences in outcomes between several European countries could not be explained by differences in hospital volumes. To understand these differences in outcomes and resection rates, with reliable case-mix adjustments, a uniform European upper gastrointestinal cancer audit with recording of standardized data is warranted. Copyright © 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.
    British Journal of Surgery 11/2012; · 4.84 Impact Factor
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    ABSTRACT: BACKGROUND: Survival estimates after curative surgery for gastric cancer are based on AJCC staging, or on more accurate multivariable nomograms. However, the risk of dying of gastric cancer is not constant over time, with most deaths occurring in the first 2 years after resection. Therefore, the prognosis for a patient who survives this critical period improves. This improvement over time is termed conditional probability of survival (CPS). Objectives of this study were to develop a CPS nomogram predicting 5-year disease-specific survival (DSS) from the day of surgery for patients surviving a specified period of time after a curative gastrectomy and to explore whether variables available with follow-up improve the nomogram in the follow-up setting. METHODS: A CPS nomogram was developed from a combined US-Dutch dataset, containing 1,642 patients who underwent an R0 resection with or without chemotherapy/radiotherapy for gastric cancer. Weight loss, performance status, hemoglobin, and albumin 1 year after resection were added to the baseline variables of this nomogram. RESULTS: The CPS nomogram was highly discriminating (concordance index: 0.772). Surviving 1, 2, or 3 years gives a median improvement of 5-year DSS from surgery of 7.2, 19.1, and 31.6 %, compared with the baseline prediction directly after surgery. Introduction of variables available at 1-year follow-up did not improve the nomogram. CONCLUSIONS: A robust gastric cancer nomogram was developed to predict survival for patients alive at time points after surgery. Introduction of additional variables available after 1 year of follow-up did not further improve this nomogram.
    Annals of Surgical Oncology 11/2012; · 4.12 Impact Factor
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    ABSTRACT: BACKGROUND: Quality assurance is increasingly acknowledged as a crucial factor for the (surgical) treatment of gastric cancer. The purpose of the current study was to define a minimum set of evidence-based quality of care indicators for the surgical treatment of locally advanced gastric cancer. METHODS: A systematic review of the literature published between January 1990 and May 2011 was performed, using search terms on gastric cancer, treatment, and quality of care. Studies were selected based on predefined selection criteria. Potential quality of care indicators were assessed based on their level of evidence and were grouped into structure, process, and outcome indicators. RESULTS: A total of 173 articles were included in the current study. For structural measures, evidence was found for the inverse relationship between hospital volume and postoperative mortality as well as overall survival. Regarding process measures, the most common indicators concerned surgical technique, perioperative care, and multimodality treatment. The only outcome indicator with supporting evidence was a microscopically radical resection. CONCLUSIONS: Although specific literature on quality of care indicators for the surgical treatment of locally advanced gastric cancer is limited, several quality of care indicators could be identified. These indicators can be used in clinical audits and other quality assurance programs.
    Annals of Surgical Oncology 10/2012; · 4.12 Impact Factor
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    ABSTRACT: To evaluate the changes in the 7th edition American Joint Committee on Cancer (AJCC) staging system for stomach cancer compared to the 6th edition; to compare the predictive accuracy of the two staging systems. In a combined database containing 2,196 patients who underwent an R0 resection for gastric adenocarcinoma, differences between the two staging systems were evaluated and stage-specific survival estimates compared. Concordance probability and Brier scores were estimated for both systems to examine the predictive accuracy. Nodal status cutoff values were changed, leading to a more even distribution for the redefined N1, N2, and N3 group. AJCC 6th edition stage II reflected a highly heterogeneous population, which is now adequately subdivided in the AJCC 7th edition into stages IIA, IIB, and IIIA. The predictive accuracy of N classification improved significantly as measured by concordance. Despite increased complexity, the predictive accuracy of AJCC 7th stage grouping was significantly worse than that of the AJCC 6th edition. The increased complexity of the 7th edition staging system is accompanied by improvements in the predictive value of nodal staging as compared to the 6th edition, but it was no better in overall stage-specific predictive accuracy. Future refinements of the tumor, node, metastasis staging system should consider whether increased complexity is balanced by improved prognostic accuracy.
    Annals of Surgical Oncology 05/2012; 19(8):2443-51. · 4.12 Impact Factor
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    ABSTRACT: Outcomes after oesophagectomy and gastrectomy vary considerably between hospitals. Possible explanations include differences in case mix, hospital volume and hospital type. The present study examined the distribution of oesophagectomies and gastrectomies between hospital types in the Netherlands, and the relationship between hospital type and outcome. Data were obtained from the nationwide Netherlands Cancer Registry. Hospitals were categorized as university hospitals (UH), non-university teaching hospitals (NUTH) and non-university non-teaching hospitals (NUNTH). Hospital type-outcome relationships were analysed by Cox regression, adjusting for case mix, hospital volume, year of diagnosis and use of multimodal therapies. Between 1989 and 2009, 10 025 oesophagectomies and 14 221 gastrectomies for cancer were performed in the Netherlands. The percentage of oesophagectomies and gastrectomies performed in UH increased from 17·6 and 6·4 per cent respectively in 1989 to 44·1 and 12·9 per cent in 2009. After oesophagectomy, the 3-month mortality rate was 2·5 per cent in UH, 4·4 per cent in NUTH and 4·1 per cent in NUNTH (P = 0·006 for UH versus NUTH). After gastrectomy, the 3-month mortality rate was 4·9 per cent in UH, 8·9 per cent in NUTH and 8·7 per cent in NUNTH (P < 0·001 for UH versus NUTH). Three-year survival was also higher in UH than in NUTH and NUNTH. Oesophagogastric resections performed in UH were associated with better outcomes but, owing to variation in outcomes within hospital types, centres of excellence cannot be designated solely on hospital type. Detailed information on case mix and outcomes is needed to identify centres of excellence.
    British Journal of Surgery 05/2012; 99(7):954-63. · 4.84 Impact Factor
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    ABSTRACT: A D2 lymphadenectomy can be considered standard of surgical care for advanced resectable gastric cancer. Currently, several multimodality strategies are used, including postoperative monochemotherapy in Asia, postoperative chemoradiotherapy in the United States, and perioperative chemotherapy in Europe. As the majority of gastric cancer patients are treated outside the framework of clinical trials, quality assurance programs, including referral to high-volume centers and clinical auditing are needed to improve gastric cancer care on a nationwide level. J. Surg. Oncol © 2012 Wiley Periodicals, Inc.
    Journal of Surgical Oncology 04/2012; · 2.64 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: A worldwide increasing incidence is seen for oesophageal adenocarcinoma, but not for oesophageal squamous cell carcinoma (SCC) and gastric cardia adenocarcinoma. Purposes of the current study were to evaluate the changing incidence rates of oesophageal and gastric cardia cancer, and to assess survival trends. Patients diagnosed with oesophageal adenocarcinoma (N=12,195) or SCC (N=9046), or gastric cardia adenocarcinoma (N=9900) between 1989 and 2008 in the Netherlands were included. Changes in European Standard Population (ESP) and relative survival over time were evaluated. Incidence rates for oesophageal adenocarcinoma increased in males (+7.5%, P<0.001) and females (+5.2%, P<0.001), while the incidence for oesophageal SCC remained stable in males (-0.2%, P=0.6) and slightly increased in females (+1.7%, P=0.001). The incidence for gastric cardia cancer decreased in males (-1.2%, P<0.006), and remained stable in females (-0.2%, P=0.7). Five-year survival for both M0 and M1 oesophageal carcinoma doubled over the last 20 years. No significant changes in survival were found for M0 and M1 gastric cardia carcinoma. In the Netherlands, a rising incidence is seen for oesophageal adenocarcinoma, but not for gastric cardia adenocarcinoma. This finding most likely reflects true changes in disease burden, rather than being the result of changes in diagnosis or classification. The increased survival for oesophageal carcinoma can be attributed to centralisation of surgery, and an increased use of multimodality therapy, factors hardly acknowledged for gastric cancer.
    European journal of cancer (Oxford, England: 1990) 02/2012; 48(11):1624-32. · 4.12 Impact Factor
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    ABSTRACT: Stomach cancer is one of the most common cancers worldwide, despite its declining overall incidence. Although there are differences in incidence, etiology and pathological factors, most studies do not separately analyze cardia and noncardia gastric cancer. Surgery is the only potentially curative treatment for advanced, resectable gastric cancer, but locoregional relapse rate is high with a consequently poor prognosis. To improve survival, several preoperative and postoperative treatment strategies have been investigated. Whereas perioperative chemotherapy and postoperative chemoradiation (CRT) are considered standard therapy in the Western world, in Asia postoperative monochemotherapy with S-1 is often used. Several other therapeutic options, although generally not accepted as standard treatment, are postoperative combination chemotherapy, hyperthermic intraperitoneal chemotherapy and preoperative radiotherapy and CRT. Postoperative combination chemotherapy does show a statistically significant but clinically equivocal survival advantage in several meta-analyses. Hyperthermic intraperitoneal chemotherapy is mainly performed in Asia and is associated with a higher postoperative complication rate. Based on the currently available data, the use of postoperative radiotherapy alone and the use of intraoperative radiotherapy should not be advised in the treatment of resectable gastric cancer. Western randomized trials on gastric cancer are often hampered by slow or incomplete accrual. Reduction of toxicity for preoperative and especially postoperative treatment is essential for the ongoing improvement of gastric cancer care.
    Therapeutic Advances in Gastroenterology 01/2012; 5(1):49-69.
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    Gastric Cancer 08/2011; 14(4):396-8. · 3.99 Impact Factor
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    ABSTRACT: Radical surgery is the cornerstone in the treatment of resectable gastric cancer. The Intergroup 0116 and MAGIC trials have shown benefit of postoperative chemoradiation and perioperative chemotherapy, respectively. Since these trials cannot be compared directly, both regimens are evaluated prospectively in the CRITICS trial. This study aims to obtain an improved overall survival for patients treated with preoperative chemotherapy and surgery by incorporating radiotherapy concurrently with chemotherapy postoperatively. In this phase III multicentre study, patients with resectable gastric cancer are treated with three cycles of preoperative ECC (epirubicin, cisplatin and capecitabine), followed by surgery with adequate lymph node dissection, and then either another three cycles of ECC or concurrent chemoradiation (45 Gy, cisplatin and capecitabine). Surgical, pathological, and radiotherapeutic quality control is performed. The primary endpoint is overall survival, secondary endpoints are disease-free survival (DFS), toxicity, health-related quality of life (HRQL), prediction of response, and recurrence risk assessed by genomic and expression profiling. Accrual for the CRITICS trial is from the Netherlands, Sweden, and Denmark, and more countries are invited to participate. Results of this study will demonstrate whether the combination of preoperative chemotherapy and postoperative chemoradiotherapy will improve the clinical outcome of the current European standard of perioperative chemotherapy, and will therefore play a key role in the future management of patients with resectable gastric cancer. clinicaltrials.gov NCT00407186.
    BMC Cancer 08/2011; 11:329. · 3.33 Impact Factor
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    ABSTRACT: In the seventh edition of the American Joint Committee on Cancer (AJCC) staging system for esophageal cancer, tumor grade was introduced as an independent determinant of stage grouping in early stage tumors. With the significantly lower prognosis for poorly differentiated early stage adenocarcinomas, patients with these tumors may become candidates for neoadjuvant therapy given an accurate identification of these tumors with preoperative staging. The objective of the current study was to investigate the accuracy of preoperative histopathologic grading and the effect of preoperative grade on tumor stage/prognostic grouping. Preoperative tumor grade was compared with postoperative tumor grade in 427 patients who underwent surgery without receiving neoadjuvant therapy for adenocarcinoma of the esophagus. The impact of preoperative tumor grade on stage/prognostic grouping was investigated. The overall accuracy of preoperative tumor grade assessment was 76% when unknown differentiation was regarded as well/moderately differentiated as recommended by the AJCC, whereas accuracy was 73% after the exclusion of tumors with unknown grade. In patients who have tumors classified as T1 or T2 and lymph node-negative (N0) (T1-T2N0) disease, 16% were assigned to a lower stage group based on preoperative pathology, whereas 5% were assigned to a higher stage group. In the T1-T2N0 group, sensitivity for detecting a poorly differentiated tumor was 0.43 (95% confidence interval [CI], 0.30-0.56), whereas specificity was 0.94 (95% CI, 0.90-0.98). With increasing use of neoadjuvant therapy, the accuracy of preoperative biopsy assessment has become increasingly important. In the current study, the accuracy of preoperative tumor grade assessment was 73%, leading to changes in AJCC stage/prognostic group in 21% of patients with T1-T2N0 esophageal adenocarcinomas. The authors concluded that caution should be exhibited in staging patients with esophageal adenocarcinoma based on preoperative biopsy data.
    Cancer 06/2011; 118(2):349-57. · 5.20 Impact Factor
  • European Journal of Cancer - EUR J CANCER. 01/2011; 47.

Publication Stats

136 Citations
101.08 Total Impact Points

Institutions

  • 2011–2014
    • Memorial Sloan-Kettering Cancer Center
      • Department of Surgery
      New York City, New York, United States
  • 2013
    • Medisch Centrum Haaglanden
      's-Gravenhage, South Holland, Netherlands
  • 2012
    • Netherlands Cancer Institute
      Amsterdamo, North Holland, Netherlands
  • 2010–2012
    • Leiden University Medical Centre
      • Department of Surgery
      Leiden, South Holland, Netherlands