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Featured researches published by Sandra A. Radema.


Journal of Clinical Oncology | 2006

Phase I Clinical Evaluation of Weekly Administration of the Novel Vascular-Targeting Agent, ZD6126, in Patients With Solid Tumors

Laurens V. Beerepoot; Sandra A. Radema; Els Witteveen; Tawnie Thomas; Catherine Wheeler; Sanford Kempin; Emile E. Voest

PURPOSEnZD6126 is a novel vascular-targeting agent that induces selective effects on the morphology of endothelial cells by disrupting the tubulin cytoskeleton. This leads to cell detachment and tumor vessel congestion, resulting in extensive central necrosis in a range of tumor xenograft models. Results from a phase I dose-escalation study of ZD6126 are reported.nnnPATIENTS AND METHODSnThirty-two patients with advanced cancer received weekly ZD6126 infusion (5 to 28 mg/m2). Assessments for safety and pharmacokinetics were performed. Circulating endothelial cells (CECs) were quantified as a pharmacodynamic marker of vascular damage.nnnRESULTSnMaximum concentrations of the active species were observed 5 to 25 minutes from the start of infusion, and decayed in a biexponential manner with a half-life of 1 to 3 hours. Maximum serum concentration and area under the time-concentration curve increased with dose in a linear fashion across the dose range of 5 to 28 mg/m2. One patient treated at 10 mg/m2 with a history of ischemic heart disease experienced acute myocardial infarction 2 weeks after drug discontinuation. Four others had asymptomatic creatine phosphokinase-muscle-brain elevation. Maximum-tolerated dose (MTD) was reached at 20 mg/m2/wk. Dose-limiting toxicities at 28 mg/m2 were hypoxia caused by pulmonary embolism and an asymptomatic decrease in left ventricular ejection fraction. No objective antitumor responses were observed. CEC levels increased in the hours after infusion, indicating potential effect of the compound on the vasculature. CONCLUSION ZD6126 administered as a weekly infusion was clinically well tolerated. The MTD was reached at 20 mg/m2.


Clinical Cancer Research | 2007

Phase I Pharmacokinetic and Pharmacodynamic Study of the Oral Protein Kinase C β-Inhibitor Enzastaurin in Combination with Gemcitabine and Cisplatin in Patients with Advanced Cancer

Jeany M. Rademaker-Lakhai; Laurens V. Beerepoot; Niven Mehra; Sandra A. Radema; Rianne J. van Maanen; Joost S. Vermaat; Els Witteveen; Carla Visseren-Grul; Luna Musib; Nathan Enas; Gertjan van Hal; Jos H. Beijnen; Jan H. M. Schellens; Emile E. Voest

Purpose: Enzastaurin targets the protein kinase C and phosphatidylinositol 3-kinase/AKT pathways to reduce tumor angiogenesis and cell proliferation and to induce cell death. A phase I trial was conducted to evaluate the feasibility of combining enzastaurin with gemcitabine and cisplatin. Experimental Design: Patients with advanced cancer received a 14-day lead-in treatment with oral enzastaurin followed by subsequent 21-day cycles of daily enzastaurin, gemcitabine on days 1 and 8, and cisplatin on day 1. Enzastaurin doses were escalated between 350 mg once daily to 500 mg twice daily, whereas gemcitabine doses were either 1,000 or 1,250 mg/m2 and cisplatin doses were either 60 or 75 mg/m2. Circulating endothelial cell numbers and CD146 and CD133 mRNA expression were evaluated as pharmacodynamic markers. Results: Thirty-three patients (median age, 58 years) were enrolled in seven dose levels. The maximum tolerated dose was not identified. Two dose-limiting toxicities (grade 2 QT interval corrected for heart rate prolongation and grade 3 fatigue) were reported. Other toxicities included grade 3/4 neutropenia (3 of 6 patients), thrombocytopenia (1 of 6 patients), grade 3 leukopenia (2 patients), and fatigue (5 patients). Enzastaurin twice daily (≥250 mg) resulted in more discontinuations and low-grade toxicities. In the combination, enzastaurin exposures decreased slightly but remained above the target of 1,400 nmol/L, whereas gemcitabine/cisplatin exposures were unaltered. Three patients (9.1%) had partial responses and 13 (39.4%) had stable disease. Measurement of circulating endothelial cell numbers and CD146 and CD133 mRNA expression did not contribute to decision-making on dose escalation. Conclusions: Recommended phase II dose is 500 mg enzastaurin once daily, 1,250 mg/m2 gemcitabine, and 75 mg/m2 cisplatin. This regimen is well tolerated with no significant alterations in the pharmacokinetic variables of any drug.


BMC Cancer | 2015

Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with colon cancer at high risk of peritoneal carcinomatosis; the COLOPEC randomized multicentre trial.

Charlotte E. L. Klaver; Gijsbert D. Musters; Willem A. Bemelman; Cornelis J. A. Punt; V.J. Verwaal; Marcel G. W. Dijkgraaf; Arend G. J. Aalbers; Jarmila D.W. van der Bilt; Djamila Boerma; Andre J. A. Bremers; Jacobus W. A. Burger; Christianne J. Buskens; Pauline Mpj Evers; Robert J. van Ginkel; Wilhelmina M.U. van Grevenstein; Patrick H. J. Hemmer; Ignace H. de Hingh; Laureen A. Lammers; Barbara L. van Leeuwen; W. J. H. J. Meijerink; Simon W. Nienhuijs; Jolien Pon; Sandra A. Radema; Bert van Ramshorst; Petur Snaebjornsson; Jurriaan B. Tuynman; Elisabeth A. te Velde; M.J. Wiezer; Johannes H. W. de Wilt; P. J. Tanis

BackgroundThe peritoneum is the second most common site of recurrence in colorectal cancer. Early detection of peritoneal carcinomatosis (PC) by imaging is difficult. Patients eventually presenting with clinically apparent PC have a poor prognosis. Median survival is only about five months if untreated and the benefit of palliative systemic chemotherapy is limited. Only a quarter of patients are eligible for curative treatment, consisting of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CR/HIPEC). However, the effectiveness depends highly on the extent of disease and the treatment is associated with a considerable complication rate.These clinical problems underline the need for effective adjuvant therapy in high-risk patients to minimize the risk of outgrowth of peritoneal micro metastases. Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) seems to be suitable for this purpose. Without the need for cytoreductive surgery, adjuvant HIPEC can be performed with a low complication rate and short hospital stay.Methods/DesignThe aim of this study is to determine the effectiveness of adjuvant HIPEC in preventing the development of PC in patients with colon cancer at high risk of peritoneal recurrence. This study will be performed in the nine Dutch HIPEC centres, starting in April 2015. Eligible for inclusion are patients who underwent curative resection for T4 or intra-abdominally perforated cM0 stage colon cancer. After resection of the primary tumour, 176 patients will be randomized to adjuvant HIPEC followed by routine adjuvant systemic chemotherapy in the experimental arm, or to systemic chemotherapy only in the control arm. Adjuvant HIPEC will be performed simultaneously or shortly after the primary resection. Oxaliplatin will be used as chemotherapeutic agent, for 30xa0min at 42-43xa0°C. Just before HIPEC, 5-fluorouracil and leucovorin will be administered intravenously. Primary endpoint is peritoneal disease-free survival at 18xa0months. Diagnostic laparoscopy will be performed routinely after 18xa0months postoperatively in both arms of the study in patients without evidence of disease based on routine follow-up using CT imaging and CEA.DiscussionAdjuvant HIPEC is assumed to reduce the expected 25xa0% absolute risk of PC in patients with T4 or perforated colon cancer to a risk of 10xa0%. This reduction is likely to translate into a prolonged overall survival.Trial registration numberNCT02231086 (Clinicaltrials.gov)


International Journal of Cancer | 2015

Colorectal signet-ring cell carcinoma: benefit from adjuvant chemotherapy but a poor prognostic factor

Niek Hugen; R. H. A. Verhoeven; Valery Lemmens; Carola J. van Aart; M.A.G. Elferink; Sandra A. Radema; Iris D. Nagtegaal; Johannes H. W. de Wilt

Colorectal signet‐ring cell carcinoma (SRCC) has been associated with poor survival compared with mucinous adenocarcinoma (MC) and the more common adenocarcinoma (AC). Efficacy of adjuvant chemotherapy in SRCC has never been assessed. This study analyzes the prognostic impact of SRCC and determines whether colonic SRCC patients benefit from adjuvant chemotherapy equally compared with MC and AC patients. Data on 196,757 colorectal cancer (CRC) patients in the period 1989–2010 was included in this Dutch nationwide population‐based study. Five‐year relative survival estimates were calculated and multivariate relative survival analyses using a multiple regression model of relative excess risk (RER) were performed. SRCC was found in 1,972 (1.0%) patients. SRCC patients presented more frequently with stage III or IV disease than AC patients (75.2% vs. 43.6%, pu2009<u20090.0001) and SRCC was more frequently found in the proximal colon (57.7 vs. 32.0%, pu2009<u20090.0001). SRCC patients had a poor 5‐year relative survival of 30.8% (95% CI 28.1–33.6%) in the colon and 19.5% (95% CI 14.7–24.8%) in the rectum compared with 56.8% (95% CI 56.4–57.1%) and 58.5% (95% CI 57.9–59.1%) for AC. This survival difference was found in stage II, but was most prominent in stage III. Compared with AC, there was no significant interaction between SRCC and adjuvant chemotherapy (RER 1.10, 95% CI 0.81–1.51), suggesting a comparable benefit from adjuvant chemotherapy in AC and SRCC. In conclusion, the prognostic impact of SRCC is dismal in both colon and rectal cancer patients, but adjuvant chemotherapy is associated with improved survival in AC, MC, and SRCC patients.


BMC Cancer | 2015

Neo-adjuvant chemotherapy followed by surgery versus surgery alone in high-risk patients with resectable colorectal liver metastases: The CHARISMA randomized multicenter clinical trial

Ninos Ayez; Eric P. van der Stok; Hans de Wilt; Sandra A. Radema; Richard van Hillegersberg; Rudi M. H. Roumen; Gerard Vreugdenhil; Pieter J. Tanis; Cornelis J. A. Punt; Cornelis H.C. Dejong; Rob L. Jansen; Henk M.W. Verheul; Koert P. de Jong; Geke A.P. Hospers; Joost M. Klaase; Marie-Cecile Legdeur; Esther van Meerten; Ferry A.L.M. Eskens; Nelly van der Meer; Bruno van der Holt; Cornelis Verhoef; Dirk J. Grünhagen

BackgroundEfforts to improve the outcome of liver surgery by combining curative resection with chemotherapy have failed to demonstrate definite overall survival benefit. This may partly be due to the fact that these studies often involve strict inclusion criteria. Consequently, patients with a high risk profile as characterized by Fong’s Clinical Risk Score (CRS) are often underrepresented in these studies. Conceptually, this group of patients might benefit the most from chemotherapy. The present study evaluates the impact of neo-adjuvant chemotherapy in high-risk patients with primary resectable colorectal liver metastases, without extrahepatic disease. Our hypothesis is that adding neo-adjuvant chemotherapy to surgery will provide an improvement in overall survival (OS) in patients with a high-risk profile.Methods/DesignCHARISMA is a multicenter, randomized, phase III clinical trial. Patients will be randomized to either surgery alone (standard treatment, arm A) or to 6 cycles of neo-adjuvant oxaliplatin-based chemotherapy, followed by surgery (arm B). Patients must be ≥ 18 years of age with liver metastases of histologically confirmed primary colorectal carcinoma. Patients with extrahepatic metastases are excluded. Liver metastases must be deemed primarily resectable. Only patients with a CRS of 3–5 are eligible. The primary study endpoint is OS. Secondary endpoints are progression free survival (PFS), quality of life, morbidity of resection, treatment response on neo-adjuvant chemotherapy, and whether CEA levels can predict treatment response.DiscussionCHARISMA is a multicenter, randomized, phase III clinical trial that will provide an answer to the question if adding neo-adjuvant chemotherapy to surgery will improve OS in a well-defined high-risk patient group with colorectal liver metastases.Trial registrationThe CHARISMA is registered at European Union Clinical Trials Register (EudraCT), number: 2013-004952-39, and in the “Netherlands national Trial Register (NTR), number: 4893.


Journal of Clinical Oncology | 2004

Phase I and pharmacologic study of enzastaurin HCl, gemcitabine and cisplatin

Jeany M. Rademaker-Lakhai; L. Beereport; Els Witteveen; Sandra A. Radema; Carla Visseren-Grul; Luna Musib; G. van Hal; Jos H. Beijnen; Jan H. M. Schellens; Emile E. Voest

3129 Background: Enzastaurin HCl (LY317615, e-HCl), an acyclic bisindolylmaleimide, is a potent inhibitor of Protein Kinase C-β isozyme. The β isoform lies in the signal cascade of VEGF and inhibition of this pathway may lead to a block in tumor angiogenesis. In preclinical studies gemcitabine (G) and cisplatin (C) exerted synergistic effects in combination with e-HCl. The objective of the study is to investigate the feasibility and toxicities of e-HCl in combination with G and C in patients (pts) with advanced malignancies, to evaluate the pharmacokinetics (PK) of all 3 agents and to recommend the Phase II doses when given in combination.nnnMETHODSnPts received a lead-in treatment period of single-agent oral e-HCl administered daily for 14 days, followed by repeated 21 day (d) combination cycles. In each combination cycle, e-HCl was taken orally on d1 - d21, G was administered as a 30 min. intravenous (iv) infusion on d1 and d8, followed by C as a 3 hr iv infusion on d1. The starting dose of e-HCl was 350 mg once daily and of G and C 1000 and 60 mg/m2, respectively.nnnRESULTSnCurrently, 17 pts have been treated at 5 dose levels. No dose limiting toxicities have been reported. Drug related adverse events to date include max. CTC grade 2 gastro-intestinal toxicities, vitiligo, anorexia, tinnitus and deafness, and max. CTC grade 3 fatigue, neutropenia, thrombocytopenia, anemia and leukopenia. PK data indicate that the geometric mean (%CV) exposures of e-HCl in Cycle 1 were 20500 (196) nM*h at 350 mg, 32100 (94.8) nM*h at 500 mg; in Cycle 2, 18500(161) nM*h at 350 mg and 25500(83.2) nM*h at 500 mg. No apparent differences in e-HCl exposures were seen when given in combination with G and C. G exposures were not altered when given in combination with e-HCl as compared to historical data. C data is pending. Due to less than dose proportional increase in e-HCl exposures in a previous study, dosing of e-HCl was changed to a bid-dosing regimen. Bid dosing started at the most recent dose level 5; 250 mg bid e-HCl, 1250 mg/m2 G and 75 mg/m2 C. 3 Pts showed a PR (prostate, papilla and head/neck cancer).nnnCONCLUSIONSnPreliminary safety and PK data enable continued dose-escalation. [Table: see text].


Lancet Oncology | 2018

Detection of residual disease after neoadjuvant chemoradiotherapy for oesophageal cancer (preSANO): a prospective multicentre, diagnostic cohort study

Bo Jan Noordman; Manon Spaander; Roelf Valkema; Bas P. L. Wijnhoven; Mark I. van Berge Henegouwen; Joel Shapiro; Katharina Biermann; Ate van der Gaast; Richard van Hillegersberg; Maarten C. C. M. Hulshof; Kausilia K. Krishnadath; S. M. Lagarde; G.A.P. Nieuwenhuijzen; Liekele E. Oostenbrug; Peter D. Siersema; Erik J. Schoon; Meindert N. Sosef; Ewout W. Steyerberg; J. Jan B. van Lanschot; Michael Doukas; Nanda C. Krak; Jan-Werner Poley; Caroline M. van Rij; Jaques Jghm Bergman; Suzanne S. Gisbertz; Hanneke W. M. van Laarhoven; Sybren L. Meijer; Lucas Goense; Nadia Haj Mohammad; Monique G.G. Hobbelink

BACKGROUNDnAfter neoadjuvant chemoradiotherapy for oesophageal cancer, roughly half of the patients with squamous cell carcinoma and a quarter of those with adenocarcinoma have a pathological complete response of the primary tumour before surgery. Thus, the necessity of standard oesophagectomy after neoadjuvant chemoradiotherapy should be reconsidered for patients who respond sufficiently to neoadjuvant treatment. In this study, we aimed to establish the accuracy of detection of residual disease after neoadjuvant chemoradiotherapy with different diagnostic approaches, and the optimal combination of diagnostic techniques for clinical response evaluations.nnnMETHODSnThe preSANO trial was a prospective, multicentre, diagnostic cohort study at six centres in the Netherlands. Eligible patients were aged 18 years or older, had histologically proven, resectable, squamous cell carcinoma or adenocarcinoma of the oesophagus or oesophagogastric junction, and were eligible for potential curative therapy with neoadjuvant chemoradiotherapy (five weekly cycles of carboplatin [area under the curve 2 mg/mL per min] plus paclitaxel [50 mg/m2 of body-surface area] combined with 41·4 Gy radiotherapy in 23 fractions) followed by oesophagectomy. 4-6 weeks after completion of neoadjuvant chemoradiotherapy, patients had oesophagogastroduodenoscopy with biopsies and endoscopic ultrasonography with measurement of maximum tumour thickness. Patients with histologically proven locoregional residual disease or no-pass during endoscopy and without distant metastases underwent immediate surgical resection. In the remaining patients a second clinical response evaluation was done (PET-CT, oesophagogastroduodenoscopy with biopsies, endoscopic ultrasonography with measurement of maximum tumour thickness, and fine-needle aspiration of suspicious lymph nodes), followed by surgery 12-14 weeks after completion of neoadjuvant chemoradiotherapy. The primary endpoint was the correlation between clinical response during clinical response evaluations and the final pathological response in resection specimens, as shown by the proportion of tumour regression grade (TRG) 3 or 4 (>10% residual carcinoma in the resection specimen) residual tumours that was missed during clinical response evaluations. This study was registered with the Netherlands Trial Register (NTR4834), and has been completed.nnnFINDINGSnBetween July 22, 2013, and Dec 28, 2016, 219 patients were included, 207 of whom were included in the analyses. Eight of 26 TRG3 or TRG4 tumours (31% [95% CI 17-50]) were missed by endoscopy with regular biopsies and fine-needle aspiration. Four of 41 TRG3 or TRG4 tumours (10% [95% CI 4-23]) were missed with bite-on-bite biopsies and fine-needle aspiration. Endoscopic ultrasonography with maximum tumour thickness measurement missed TRG3 or TRG4 residual tumours in 11 of 39 patients (28% [95% CI 17-44]). PET-CT missed six of 41 TRG3 or TRG4 tumours (15% [95% CI 7-28]). PET-CT detected interval distant histologically proven metastases in 18 (9%) of 190 patients (one squamous cell carcinoma, 17 adenocarcinomas).nnnINTERPRETATIONnAfter neoadjuvant chemoradiotherapy for oesophageal cancer, clinical response evaluation with endoscopic ultrasonography, bite-on-bite biopsies, and fine-needle aspiration of suspicious lymph nodes was adequate for detection of locoregional residual disease, with PET-CT for detection of interval metastases. Active surveillance with this combination of diagnostic modalities is now being assessed in a phase 3 randomised controlled trial (SANO trial; Netherlands Trial Register NTR6803).nnnFUNDINGnDutch Cancer Society.


Nutrients | 2018

Dietary Intake of Magnesium or Calcium and Chemotherapy-Induced Peripheral Neuropathy in Colorectal Cancer Patients

Evertine Wesselink; Renate M. Winkels; Harm van Baar; Anne Geijsen; Moniek van Zutphen; Henk van Halteren; Bibi M.E. Hansson; Sandra A. Radema; Johannes H. W. de Wilt; Ellen Kampman; Dieuwertje E. Kok

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and severe side-effect in colorectal cancer (CRC) patients. This study assessed the association between habitual dietary intake of magnesium or calcium and prevalence and severity of chronic CIPN in CRC patients receiving adjuvant chemotherapy. For this prospective cohort study, 196 CRC patients were considered. Magnesium and calcium intake was determined using a food frequency questionnaire at diagnosis, during and after chemotherapy. Chronic CIPN was assessed 12 months after diagnosis using the quality of life questionnaire CIPN20. Prevalence ratios were calculated to assess the association between magnesium or calcium intake and the prevalence of CIPN. Multivariable linear regression analysis was used to assess the association between magnesium or calcium intake and severity of CIPN. CIPN was reported by 160 (82%) patients. Magnesium intake during chemotherapy was statistically significantly associated with lower prevalence of CIPN (prevalence ratio (PR) 0.53, 95% confidence interval (CI) 0.32, 0.92). Furthermore, higher dietary intake of magnesium during (β −1.08, 95% CI −1.95, −0.22) and after chemotherapy (β −0.93, 95% CI −1.81, −0.06) was associated with less severe CIPN. No associations were found for calcium intake and the prevalence and severity of CIPN. To conclude, we observed an association between higher dietary magnesium intake and lower prevalence and severity of CIPN in CRC patients.


The Breast | 2018

Group medical consultations (GMCs) and tablet-based online support group sessions in the follow-up of breast cancer: A multicenter randomized controlled trial

Annemiek Visser; J.B. Prins; Lisette Jansen; Sandra A. Radema; Margrethe S. Schlooz; Thijs van Dalen; Hanneke W. M. van Laarhoven

OBJECTIVEnGroup medical consultations (GMCs) provide individual medical visits in the presence of ≤7 peer-patients. In the follow-up of breast cancer, we evaluated the efficacy of a new type of blended care My-GMC, a GMC combined with a tablet-based online app, consisting of three online support group sessions (SGS) and additional information.nnnMETHODSnThis randomized controlled trial compared the effect of My-GMC (nu202f=u202f59) with one individual medical visit (nu202f=u202f50) (care as usual). Between-group differences on the outcomes distress and empowerment were analyzed 1 week, 3 and 6 months after the visit.nnnRESULTSnNo between-group differences were found for the primary outcomes distress and empowerment. More themes were discussed in GMCs compared to individual visits. Significantly more patients experienced peer-support in GMCs (78%) than via the online app (29%). Satisfaction with the online app was low.nnnCONCLUSIONSnMy-GMC did not result in improvements in distress or empowerment, which might partly be explained by low baseline distress levels. This paper provides valuable information concerning factors on organizational level as well as individual level influencing the evaluation of a blended care intervention.nnnPRACTICE IMPLICATIONSnMy-GMC provided an innovative alternative, combining professional and peer-support in face-to-face and online SGS, resulting in additional information provision and peer-support. Further improvement of the apps is needed to improve user satisfaction.nnnNETHERLANDS TRIAL REGISTERnNTR3771.


Journal of Clinical Oncology | 2017

Impact of skeletal muscle index (SMI) loss during palliative systemic treatment (Tx) on time to progression and overall survival (OS) in metastatic colorectal cancer (mCRC) patients.

Sophie A. Kurk; Petra H.M. Peeters; Rebecca K. Stellato; Bram Dorresteijn; Marion Jourdan; Geert-Jan Creemers; Frans Erdkamp; Felix E. de Jongh; Petrus Alouisius Maria Kint; Boelo Jan Poppema; Sandra A. Radema; Lieke H. J. Simkens; Bea Tanis; Manuel Lucien Roy Tjin-A-Ton; Ankie Van Der Velden; Cornelis J. A. Punt; Miriam Koopman; Anne Maria May

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Cornelis Verhoef

Erasmus University Rotterdam

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M.A.G. Elferink

University of East Anglia

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A ten Tije

Erasmus University Rotterdam

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Emile E. Voest

Netherlands Cancer Institute

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J.H.W. de Wilt

Radboud University Nijmegen

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Felix E. de Jongh

Erasmus University Rotterdam

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