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Dive into the research topics where A.L. Vahrmeijer is active.

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Featured researches published by A.L. Vahrmeijer.


British Journal of Surgery | 2013

Clinical trial of combined radio- and fluorescence-guided sentinel lymph node biopsy in breast cancer.

Boudewijn E. Schaafsma; F.P.R. Verbeek; Daphne Dd Rietbergen; Bernies van der Hiel; Joost R. van der Vorst; Gerrit-Jan Liefers; John V. Frangioni; Cornelis J. H. van de Velde; Fijs W. B. van Leeuwen; A.L. Vahrmeijer

Combining radioactive colloids and a near‐infrared (NIR) fluorophore permits preoperative planning and intraoperative localization of deeply located sentinel lymph nodes (SLNs) with direct optical guidance by a single lymphatic tracer. The aim of this clinical trial was to evaluate and optimize a hybrid NIR fluorescence and radioactive tracer for SLN detection in patients with breast cancer.


Recent results in cancer research | 1998

Isolated Hepatic Perfusion with Tumor Necrosis Factor α and Melphalan: Experimental Studies in Pigs and Phase I Data from Humans

M. R. de Vries; I. H. Borel Rinkes; C.J.H. van de Velde; T. Wiggers; R.A.E.M. Tollenaar; P.J.K. Kuppen; A.L. Vahrmeijer; A. M. M. Eggermont

We report our experience with isolated hepatic perfusion (IHP) with tumor necrosis factor (TNF) and melphalan in an experimental pig study and of a phase I study in humans. IHP was performed with inflow catheters in the hepatic artery and portal vein and an outflow catheter in eh caval vein. An extracorporeal venovenous bypass was used. IHP consisted of a 60-min perfusion with hyperthermia (> 41 degrees C). For the pig protocol rhTNF alpha 50 micrograms/kg alone (n = 5) or rhTNF alpha 50 micrograms/kg plus melphalan 1 mg/kg (n = 3) were added. In two control pigs no drugs were added. In the phase I study, patients received melphalan 1 mg/kg with 0.4 mg rhTNF alpha (n = 8) or 0.8 mg rhTNF alpha (n = 1). After the perfusion the liver was washed with Macrodex before vascular continuity was restored. All pigs but one survived the procedure. Systemic leakage was less than 0.02%. Transient, mild liver toxicity was seen in all pigs, including controls, as demonstrated by liver enzyme assays and histology. There was no significant hemodynamic, cardiopulmonary hematological, or renal toxicity. In the phase I clinical study there was leakage in one patient (cumulative leakage 20%). There were three perioperative deaths (one possibly drug-related). All patients demonstrated significant hepatotoxicity. Survival ranged from 6 to 26 months (median 10.3 months). All patients demonstrated a tumor response (partial response 5/6, 1/6 stable disease) with a median duration of 18 weeks. In contrast to our pig program, many problems were encountered in the phase I study. By using both the hepatic artery and portal vein for IHP we encountered more toxicity than expected based on data from the pig program, resulting in fatal coagulative disturbances in one patient who received the second rhTNF alpha dose. Furthermore, local control after one IHP with TNF alpha and melphalan is only temporary.


The Journal of Nuclear Medicine | 2016

Successful Translation of Fluorescence Navigation During Oncologic Surgery: A Consensus Report

Eben L. Rosenthal; Jason M. Warram; Esther de Boer; James P. Basilion; Merrill A. Biel; Matthew Bogyo; Michael Bouvet; Brian E. Brigman; Yolonda L. Colson; Steven R. DeMeester; Geoffrey C. Gurtner; Takeaki Ishizawa; Paula Jacobs; Stijn Keereweer; Joseph C. Liao; Quyen T. Nguyen; James M. Olson; Keith D. Paulsen; Dwaine Rieves; Baran D. Sumer; Michael F. Tweedle; A.L. Vahrmeijer; Jamey P. Weichert; Brian C. Wilson; Kurt R. Zinn; Gooitzen M. van Dam

Navigation with fluorescence guidance has emerged in the last decade as a promising strategy to improve the efficacy of oncologic surgery. To achieve routine clinical use, the onus is on the surgical community to objectively assess the value of this technique. This assessment may facilitate both Food and Drug Administration approval of new optical imaging agents and reimbursement for the imaging procedures. It is critical to characterize fluorescence-guided procedural benefits over existing practices and to elucidate both the costs and the safety risks. This report is the result of a meeting of the International Society of Image Guided Surgery (www.isigs.org) on February 6, 2015, in Miami, Florida, and reflects a consensus of the participants’ opinions. Our objective was to critically evaluate the imaging platform technology and optical imaging agents and to make recommendations for successful clinical trial development of this highly promising approach in oncologic surgery.


European Surgical Research | 2011

Near-Infrared Fluorescence Imaging in Patients Undergoing Pancreaticoduodenectomy

Merlijn Hutteman; J.R. van der Vorst; J.S.D. Mieog; Bert A. Bonsing; Henk H. Hartgrink; P.J.K. Kuppen; Clemens W.G.M. Löwik; John V. Frangioni; C.J.H. van de Velde; A.L. Vahrmeijer

Background: Intraoperative visualization of pancreatic tumors has the potential to improve radical resection rates. Intraoperative visualization of the common bile duct and bile duct anastomoses could be of added value. In this study, we explored the use of indocyanine green (ICG) for these applications and attempted to optimize injection timing and dose. Methods: Eight patients undergoing a pancreaticoduodenectomy were injected intravenously with 5 or 10 mg ICG. During and after injection, the pancreas, tumor, common bile duct and surrounding organs were imaged in real time using the Mini-FLARE™ near-infrared (NIR) imaging system. Results: No clear tumor-to-pancreas contrast was observed, except for incidental contrast in 1 patient. The common bile duct was clearly visualized using NIR fluorescence, within 10 min after injection, with a maximal contrast between 30 and 90 min after injection. Patency of biliary anastomoses could be visualized due to biliary excretion of ICG. Conclusion: No useful tumor demarcation could be visualized in pancreatic cancer patients after intravenous injection of ICG. However, the common bile duct and biliary anastomoses were clearly visualized during the observation period. Therefore, these imaging strategies could be beneficial during biliary surgery in cases where the surgical anatomy is aberrant or difficult to identify.


Biochemical Pharmacology | 1999

Effect of glutathione depletion on inhibition of cell cycle progression and induction of apoptosis by melphalan (L-phenylalanine mustard) in human colorectal cancer cells

A.L. Vahrmeijer; Jan Hein van Dierendonck; Jan Schutrups; Cornelis J. H. van de Velde; Gerard J. Mulder

Intracellular levels of glutathione have been shown to affect the sensitivity of cells to cell death-inducing stimuli, as well as the mode of cell death. We found in five human colorectal cancer cell lines (HT-29, LS-180, LOVO, SW837, and SW1116) that GSH depletion by L-buthionine-[S,R]-sulfoximine (BSO) below 20% of control values increased L-phenylalanine mustard (L-PAM; Melphalan) cytotoxicity 2- to 3-fold. Effects on kinetics of both cell cycle progression and cell death were further investigated in the HT-29 cell line. BSO treatment alone had no effect on cell cycle kinetics, but did enhance the inhibition of S phase progression as induced by L-PAM; at high concentration of of L-PAM, BSO pretreatment resulted in blockage in all phases of the cell cycle. Yet, BSO pretreatment did not affect the intracellular L-PAM content. L-PAM induced apoptosis in both normal and GSH-depleted cells. A combination of annexin V labeling and propidium iodide staining revealed that even the higher concentration of L-PAM (420 microM) did not induce apoptosis until 48 hr after treatment, but that induction of cell death was markedly accelerated as a result of GSH depletion: 48 hours after L-PAM (420 microM) treatment, GSH-depleted cells showed a 4-fold increase in DNA fragmentation and a 7-fold increase in the fraction of apoptotic (annexin V-positive) cells as compared to cells with normal GSH levels. Various antioxidant treatment modalities could not prevent this potentiating effect of GSH depletion on L-PAM cytotoxicity, suggesting that reactive oxygen species do not play a role. These data show that after BSO treatment the mode of L-PAM-induced cell death does not necessarily switch from apoptosis to necrosis.


British Journal of Cancer | 2014

Clinical prognostic value of combined analysis of Aldh1, Survivin, and EpCAM expression in colorectal cancer

Inès J. Goossens-Beumer; Eliane C.M. Zeestraten; Anne Benard; T Christen; Marlies S. Reimers; R. Keijzer; Cornelis F. M. Sier; G.J. Liefers; H. Morreau; Hein Putter; A.L. Vahrmeijer; C.J.H. van de Velde; P.J.K. Kuppen

Background:Tumour aggressiveness might be related to the degree of main cancer hallmark acquirement of tumour cells, reflected by expression levels of specific biomarkers. We investigated the expression of Aldh1, Survivin, and EpCAM, together reflecting main cancer hallmarks, in relation to clinical outcome of colorectal cancer (CRC) patients.Methods:Immunohistochemistry was performed using a tumour tissue microarray of TNM (Tumour, Node, Metastasis)-stage I–IV CRC tissues. Single-marker expression or their combination was assessed for associations with the clinical outcome of CRC patients (N=309).Results:Increased expression of Aldh1 or Survivin, or decreased expression of EpCAM was each associated with poor clinical outcome, and was therefore identified as clinically unfavourable expression. Analyses of the combination of all three markers showed worse clinical outcome, specifically in colon cancer patients, with an increasing number of markers showing unfavourable expression. Hazard ratios ranged up to 8.3 for overall survival (P<0.001), 36.6 for disease-specific survival (P<0.001), and 27.1 for distant recurrence-free survival (P<0.001).Conclusions:Our data identified combined expression levels of Aldh1, Survivin, and EpCAM as strong independent prognostic factors, with high hazard ratios, for survival and tumour recurrence in colon cancer patients, and therefore reflect tumour aggressiveness.


British Journal of Obstetrics and Gynaecology | 2013

Near-infrared fluorescence sentinel lymph node biopsy in vulvar cancer: a randomised comparison of lymphatic tracers.

Boudewijn E. Schaafsma; Fpr Verbeek; Aaw Peters; J.R. van der Vorst; C.D. de Kroon; Mie van Poelgeest; Jbmz Trimbos; Cjh van de Velde; John V. Frangioni; A.L. Vahrmeijer; Katja N. Gaarenstroom

This study aims to confirm the feasibility of near‐infrared (NIR) fluorescence imaging for sentinel lymph node (SLN) biopsy in vulvar cancer and to compare the tracer indocyanine green (ICG) bound to human serum albumin (HSA) versus ICG alone. Women received 99mTc‐nanocolloid and patent blue for SLN detection. Subsequently, women randomly received ICG:HSA or ICG alone. In 24 women, 35 SLNs were intraoperatively detected. All SLNs detected were radioactive and NIR fluorescent and 27 (77%) were blue. No significant difference was found between ICG:HSA and ICG alone. This trial confirms the feasibility of NIR fluorescence imaging for SLN mapping in vulvar cancer.


Annals of Oncology | 2008

Isolated hepatic melphalan perfusion of colorectal liver metastases: outcome and prognostic factors in 154 patients

L.B.J. van Iersel; Hans Gelderblom; A.L. Vahrmeijer; E. L. van Persijn van Meerten; F.G.J. Tijl; Hein Putter; Henk H. Hartgrink; P.J.K. Kuppen; J. W. R. Nortier; R.A.E.M. Tollenaar; C.J.H. van de Velde

BACKGROUNDnThe aim of this study was to identify prognostic factors for local and systemic failure after isolated hepatic perfusion (IHP) with 200 mg melphalan in patients with colorectal liver metastases.nnnPATIENTS AND METHODSnHundred and fifty-four patients were selected for IHP and underwent laparotomy. Patients were monitored for response, toxicity and survival. Univariate and multivariate analyses were carried out to identify prognostic factors for hepatic response and progression-free and overall survival.nnnRESULTSnHepatic response rate was 50% with a median progression-free and overall survival of, respectively, 7.4 and 24.8 months. In multivariate analyses, absence of ability to perfuse through the hepatic artery (P = 0.003), severe postoperative complications (P = 0.048) and >10 liver metastases (P = 0.006) adversely influenced overall survival and no adjuvant chemotherapy adversely influenced progression-free survival.nnnCONCLUSIONnThis is the first study to report prognostic factors for survival after IHP. Possibly, overall and disease-free survival can increase if preoperative screening is improved. In future studies on IHP, adjuvant chemotherapy should be considered.


Biochemical Pharmacology | 2000

Development of resistance to glutathione depletion-induced cell death in CC531 colon carcinoma cells: association with increased expression of bcl-2.

A.L. Vahrmeijer; Rob W.M. Hoetelmans; Gerard J. Mulder; Jan Schutrups; Ronald L.P. van Vlierberghe; Cornelis J. H. van de Velde; Jan Hein van Dierendonck

The glutathione (GSH) level of CC531 rat colorectal cancer cells is readily decreased by exposure to buthionine sulfoximine (BSO), an inhibitor of GSH synthesis; at 25 microM BSO, these cells died in a non-apoptotic fashion. By continuous exposure of CC531 cells to increasing concentrations of BSO, we obtained a BSO-resistant cell line (CCBR25) that was 50 times more resistant to BSO than the parental cell line. Whereas the GSH content of CCBR25 and CC531 cells was similar, the former contained a much higher level of the Bcl-2 protein. After stable transfection of CC531 cells with the human bcl-2 gene, the resulting Bcl-2-overexpressing cell line appeared to be 9 times more resistant to BSO than the parental cell line. These findings suggest that the Bcl-2 protein offers resistance against the cytotoxic effect of severe GSH depletion.


European Journal of Cancer | 1995

TREATMENT OF COLORECTAL CANCER METASTASES CONFINED TO THE LIVER

A.L. Vahrmeijer; J. H. Van Dierendonck; C.J.H. van de Velde

Hepatic metastases are a major cause of death in patients with disseminated colorectal cancer. The prognosis of patients with hepatic metastases is very poor and mainly determined by the extent of hepatic disease at presentation. In these patients, the goal of any treatment is to obtain a complete tumour remission in the liver; this is the only way to obtain a significant survival benefit. In this overview, we summarise data from (i) studies comparing survival of patients after primary resection of liver metastases with survival after repeat liver resections, (ii) studies comparing hepatic arterial infusion of fluoropyrimidines with systemic delivery of these anticancer drugs, and (iii) phase I/II studies on isolated liver perfusion (ILP) with alkylating compounds. Furthermore, we discuss alternative strategies to combat liver metastases, including those taking advantage of an ILP setting.

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C.J.H. van de Velde

Leiden University Medical Center

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Boudewijn E. Schaafsma

Leiden University Medical Center

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John V. Frangioni

Beth Israel Deaconess Medical Center

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J.S.D. Mieog

Leiden University Medical Center

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F.P.R. Verbeek

Leiden University Medical Center

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J.R. van der Vorst

Leiden University Medical Center

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Merlijn Hutteman

Leiden University Medical Center

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Bert A. Bonsing

Leiden University Medical Center

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P.J.K. Kuppen

Leiden University Medical Center

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