In the year 2006 the multidisciplinary breast cancer research team was formally appointed by GROW organisation, as it is an important tumour type with a high tumour incidence and being the focus of research of many departments within the University Hospital Maastricht and University Maastricht.

The breast cancer research group will focus on 5 different research topics, that is, 1) follow-up strategies, 2) breast imaging studies, 3) treatment evaluations, 4) isolated tumour cells and micro metastases, and 5) prognostic and predictive marker studies.

1) Follow-up strategies

In June 2005 a multicentre trial was started, with patients being randomized into one of four arms: 1) follow-up as usual, which means four outpatient clinic visits in the first year and in two visits in the second year, with a yearly mammography; 2) outpatient clinic follow-up visits once a year with a mammography in combination with telephone interviews by a nurse-practitioner (NP) at the same time points as usual follow-up; 3) similar to arm 1, combined with a group intervention aimed at education, an Info-Care-Program (ICP); 4) similar to arm 2, combined with an ICP. The aim of this study is to investigate the cost-effectiveness of different follow-up strategies in curatively treated breast cancer patients. In total we will include 320 breast cancer patients. The primary endpoint of this study is QoL at 12 months after treatment.

Since the start of the study in 2005, 172 patients have been included, of which 121 in 2006. Both nurse practitioners and patients report encouraging experiences with the telephone follow-up. Also, the Info-Care-Programme has been well-received by patients (average mark 8 out of 10). There are only a few drop-outs (<5%) and at the moment 96% of questionnaires and 92% of cost-diaries have been returned. To conclude, the trial has been well-received on both national and international conferences and two manuscripts have been accepted for publication in international journals.

This project is entitled ‘Improving the efficiency and quality of follow-up after curative treatment for breast cancer', coordinated by dr. L. Boersma (Maastro Clinic), and supported by ZonMW for the time period 2005-2008. 

2) Breast imaging studies

There has been a marked increase in demand for radiologic services which has not been met by commensurate increase in radiologist staffing. A possible solution to this problem is the concept of ‘skill mixing', in which trained radiologic technicians are used to perform duties previously reserved to radiologists. This project will assess the effectiveness of training specialised breast technicians, who are involved in the performance and interpretation of diagnostic mammograms in daily clinical practice. Technicians are trained in the pre-screening of mammograms, in which they distinguish patients with fully normal test results from cases with any abnormality. As the radiologist can then devote his attention mainly to the cases thought to be abnormal, time and costs can be saved, leading to a gain in quality and efficiency of diagnostic breast imaging. In the study, the costs and effects of this innovative strategy are compared to the current routine process of breast imaging.

This project is entitled ‘Performance of specialised breast technicians in diagnostic breast imaging (PERSPECT study)', coordinated by dr. K. Flobbe (dept. Radiology azM/UM), and supported by ZonMW for the time period 2005-2007.

The routine diagnostic work up in patients suspected with breast disease consists of clinical examination, mammography and ultrasonography when indicated. The increasing use of additional ultrasonography in these patients without a scientific basis has led to questions about the appropriateness and efficiency of its application. In a prior, large prospective study (MAMMOED-1 study) subgroups of patients were identified who benefit most from additional ultrasonography and subgroups in whom it does not yield additional diagnostic information. Based on these data, evidence-based guidelines were designed for appropriate application of breast ultrasonography, The current study concerns the further development of these guidelines, as well as the development of these guidelines, as well as the development of cost-effective implementation strategies, by means of an implementation study in a multicentre radiological setting.

Furthermore, on behalf of outcome evaluation of the implementation study, performance indicators are developed which can be used for quality assurance in diagnostic breast imaging.

This project is entitled ‘Implementation of evidence-based guidelines for appropriate use of ultrasonography in diagnostic breast imaging (MAMMOED-2 study)', coordinated by dr. K. Flobbe (dept. Radiology azM/UM), and supported by ZonMW for the time period 2004-2007. 

3) Treatment evaluations

Two projects on surgery are funded by ZonMW.

Fast track surgery: with optimal use of modern peri-operative techniques the physical and psychological impact of surgery is minimised, resulting in a shorter recovery period after surgery. After a successful breast cancer surgery fast track program in the University Hospital Maastricht, this is now a project in cooperation with four other Dutch hospitals.

A next project concerns the development of a shortened recovery program to reduce the hospital stay.

According to current guidelines, postmenopausal women with a hormone sensitive breast tumour and an indication for adjuvant endocrine treatment, may be treated with 2-3 years tamoxifen, subsequently switching to an aromatase inhibitor for another 2-3 years. At the moment it is not known whether a total endocrine treatment duration of 5 years is optimal. In the DATA study, patients on treatment with tamoxifen, will be randomized between 3 or 6 years of subsequent treatment with an aromatase inhibitor (anastrozole). Primary endpoint is the 5-year disease-free survival. The required number of patients is 1900. The DATA study is a national study within the framework of the BOOG (borstkanker onderzoeksgroep Nederland) and has received central approval on December 21, 2006, with 31 centres open for inclusion at the end of 2006. By the first of January 2007, 82 patients were included.

This national BOOG study is entitled ‘A prospective randomised, open, multicentre, phase III study to assess different Durations of Anastrozole therapy after 2 to 3 years Tamoxifen as Adjuvant therapy in postmenopausal women with breast cancer (the DATA study)', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by AstraZeneca for the time period 2006-2015.

Patients with newly diagnosed large resectable (3 cm and above and/or lymph node positive) or locally advanced breast cancer will be randomly assigned to one of two treatment arms with neo-adjuvant chemotherapy. The study is designed to compare the efficacy and tolerability of neoadjuvant chemotherapy with AC followed by T (adriamycine, cyclophosphamide, taxotere) versus TAC (with upfront T) in 200 breast cancer patients. The primary endpoint is the pathologic complete response (pCR) rate to neoadjuvant chemotherapy at surgery. Secondary endpoints are the delivered chemotherapy dose and dose-intensity, the tolerability, the clinical responses correlated to pathological responses, the value of breast MRI scanning in evaluating response as compared to clinical palpation, ultrasound techniques and histo-pathological outcome (optional side study), the false-negative rate of the sentinel node biopsy after neoadjuvant chemotherapy (optional side study), the disease-free (DFS) and overall survival (OS) after 3 and 5 years follow-up, the relation between pCR and DFS/OS, and the feasibility of the criteria for reporting pathological tumour response in surgical breast and axillary node resection specimens. The prognostic and predictive value of tumour- and molecular markers, including ER, PgR, c-erbB2, microarray and other tumour characteristic analyses, will be analysed in another optional side study.

This national BOOG study is entitled ‘Sequential vs upfront intensified neoadjuvant chemotherapy in patients with large resectable or locally advanced breast cancer (the INTENS study)', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by Sanofi Aventis and Amgen, for the time period 2006-2012.

4) Isolated tumour cells and micro metastases

In the multicentre VAZ 01122 study a cohort of breast cancer patients eligible to undergoing a sentinel lymph node procedure are being studied to address three main questions: 1. the impact of presence of isolated tumour cells or micro metastases in the sentinel lymph node(s) to predict metastatic involvement in the completion axillary lymph nodes; 2. differences between institutions in sentinel lymph node pathology protocols and the impact on performance of additional axillary lymph node dissection; 3. cost-effectiveness of performing a sentinel lymph node procedure in breast cancer. A total of 540 eligible patients have been included, and have already resulted in 3 publications in the Annals of Oncology and the Annals of Surgical Oncology.

This multicentre study is entitled ‘VAZ-DO 2001-122: Changes in diagnostics and therapy in breast cancer due to introduction of the sentinel lymph node procedure', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by CvZ, for the time period 2002-2008.

The MIRROR study is a national cohort study, to determine the prognostic relevance of isolated tumour cells and micrometastases in the axillary lymph nodes and the impact of adjuvant systemic therapy on prognosis, as at present there is worldwide no consensus on whether to systemically treat or not to treat and look for these small tumour involvements. Primary endpoint is 5-years disease free survival. The cost-effectiveness of delivering adjuvant systemic therapy is another primary endpoint. Patients who underwent a sentinel lymph node procedure in 2005 or before and who have favourable primary tumour characteristics are eligible. In total 3000 patients will be included: one cohort without lymph node metastases and without adjuvant systemic therapy; one cohort with micro metastases and/or isolated tumour cells without adjuvant systemic therapy; and one cohort with micro metastases and/or isolated tumour cells with adjuvant systemic therapy. The patient selection is based on data of the comprehensive cancer centres (IKCs). Information on therapy and follow-up will be collected by the registration managers of the IKCs. Central pathology revision is performed by two pathologists. Several side studies will be performed.

This national BOOG study is entitled ‘Micrometastases and Isolated tumour cells: Relevant and Robust Or Rubbish, the MIRROR study in breast cancer', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by ZonMW, for the time period 2006-2009.

5) prognostic and predictive marker studies

To study the prognostic and predictive impact of different tumour markers and to obtain insight in different molecular pathways, research has been done and will continue in co-operation with the Radboud University Nijmegen (prof. dr. C.G.J. Sweep, prof. dr. R. Holland and prof. dr. A. Verbeek), and new liaisons have been initiated within the azM/UM with the research groups of prof. A.W. Griffioen, prof. dr. A. De Bruïne and dr. M. van Engeland.

In a prospective local study in 45 newly diagnosed breast cancer patients, the genetic changes at the tumour cell level caused by cox-2 inhibition, are being studied. At present, 23 patients have been included.

This study is entitled ‘cDNA micro-array analysis in human breast cancers before and after treatment with COX-2 inhibitor celecoxib: the development of predictive factors', coordinated by Dr. P.S.G.J. Hupperets (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by Pfizer, azM, FHLM, for the time period 2001-2008.

Selected publications

Hupperets PS, Tjan-Heijnen VC.
Primary or secondary G-CSF prophylaxis to support TAC chemotherapy in Breast Cancer. Ann Oncol 2006; 17:1181-1183 

Foekens JA, Atkins D, Zhang Y, Sweep CGJ, Harbeck N, Paradiso A, Cufer T, Siewerts A, Talantov D, Span PN, Tjan-Heijnen VCG, Zito A, Specht K, Hoefler H, Golouh R, Schittulli F, Schmitt M, Beex LVAM, Klijn JGM and Wang X.
Multi-center validation of a gene expression based prognostic signature in lymph node-negative primary breast cancer.
J Clin Oncol, 2006; 24: 1665-1671

Span PN, Tjan-Heijnen VCG, Heuvel JJTM, de Kok JB, Foekens JA. Sweep CGJ.
Do the surviving (BIRC5) splice variants modulate or add to the prognostic value of total surviving in breast cancer?
Clinical Chemistry, 2007; 52: 1693-1700
 

Funding started in 2006

In vitro functional assays to assess pathogennicity of genetic variants in the breast cancer genes BRCA1 and BRCA2, coordinated by dr. E.B. Gómez García, Dr. M.R. Block (dept. of Clinical Genetics, azM/UM), funded by Science and Technology Foundation (Portugal)

Identification of pathogenic BRCA1 and BRCA2 sequence variants by gene-expression profiling, coordinated by dr. E.B. Gómez García, Dr. M.R. Block (dept. of Clinical Genetics, azM/UM), funded by Calouste Gulbenkian Foundation (Portugal)

A prospective randomised, open, multicentre, phase III study to assess different Durations of Anastrozole therapy after 2 to 3 years Tamoxifen as Adjuvant therapy in postmenopausal women with breast cancer (the DATA study)', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by AstraZeneca for the time period 2006-2015.

Sequential vs upfront intensified neoadjuvant chemotherapy in patients with large resectable or locally advanced breast cancer (the INTENS study)', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by Sanofi Aventis and Amgen, for the time period 2006-2012.

Micrometastases and Isolated tumour cells: Relevant and Robust Or Rubbish, the MIRROR study in breast cancer', coordinated by prof. dr. V.C.G. Tjan-Heijnen (div. Medical Oncology, dept. Internal Medicine, azM/UM), and supported by ZonMW, for the time period 2006-2009.

Research group

Prof.dr. V.C.G. Tjan-Heijnen, project leader
Dr. R. Beets-Tan
Dr. L. Boersma
Prof.dr. J.M.A. van Engelshoven
Dr. K. Flobbe
Dr. E.B. Gómez Garcia
Dr. P.S.G.J. Hupperets
Prof.dr. M.F. von Meyenfeldt

PhD students

M. de Boer
M. Bolster (Nijmegen)
P. Bult (Nijmegen)
M.L. Kimman
L. Vercauteren
B. Vriens 

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Cell-therapy

Cell-therapy focuses on using the immune system to eliminate cancer cells. This can be done by using the patients own immune system/cells or using donor cells. An example of making use of a patients' own system is the development of a vaccine. The concept of vaccine development in cancer is comparable to vaccine in infectious diseases, where the immune system is stimulated to fight against invaders.

Making use of a donor immune system to fight cancer is possible because the immune system of the donor will recognize the patients cells - including cancer cells - as non-self, a reason to kill them. Both research lines and 2006 activities are described below.

Vaccine development

The focus of this research line is the development of dendritic cells (DC = antigen presenting cell). DC do have the capacity to present antigens to the helper and effector cells of the immune system. They are the central regulators of our immune system. In a normal immune response - like infections - DC pick up these pathogens. After activation of the DC they will migrate to lymfnodes where the immune system is activated.

It is possible to culture DC in the laboratory (in vitro) from peripheral blood monocytes and from bone marrow stem cells. Both techniques are available in our laboratory. The concept of the vaccine is to load DC with tumour-antigens (peptide, protein etc) and to inject the DC into the patient. We have selected Mucine-1 as tumour-antigen since it is present on several malignant cells, including breast cancer, lung cancer, ovarian cancer and M. Myeloma. We have realised loading of the DC with this mucine-1 making use of peptides and/or an adenoviral vector. This second method induces high expression of mucin-1 on the DC including a pattern that is similar to tumour cells (various glycosylation forms). This is an important step in inducing glycoform specific immune responses. It need to be proven however if expression at the membrane correlates to presentation (via HLA-molecules) to immune T cells.

An important aspect of the research is to select the best possible DC. Since DC vaccination in the clinic is not yet successful the method still has to be improved. One of the most challenging issues in DC preparation is how to make a DC that activates the immune system and can travel to the lymph node, as a DC does in a normal immune response. Our latest results - still to be improved - show that we have a DC that meet all the requirements.

In 2006 we also studied the presence of Mucine-1 on M. Myeloma, demonstrating that tumour specific patterns of Mucine-1 are also present on this tumour, making this disease a good candidate for immunotherapy. In contrast, this tumour specific pattern is not present on acute myeloid leukaemia. The fact that we might be able to use tumour specific Mucine-1 in M. Myeloma is challenging. Since Mucine-1 is thought to be a relevant structure for the interaction of malignant myeloma cells and bone marrow stromal cells, an interaction critical for tumour growth.

An analysis was performed on the presence of Mucine-1 in the thymus. Since tolerance is regulated in this organ it is relevant to know if the tumour specific patterns of Mucine-1 can be find in the thymus as well. This is not the case, making it more likely that an adequate immune response against these antigens can be realized. We could demonstrate that Mucine-1 is present in its full glycoform on thymic medullary epithelial cells, but not the tumour specific glycoforms. These medullary epithelials cells play a crucial role for tolerance induction (manuscript accepted in 2006).

Donor transplantations

Donor transplantations do have several limitations. One of them is the availability of donors. By using haploidentical donors (one chromosome with the relevant major histocompatibility antigens in common) nearly all patients will have a donor (figure). A second limitation is toxicity, that can be reduced by using a so called non-myeloablative (or "mini-") transplantations.

We used a combination of these two (mini-transplant and haploidentical donor) in a new mouse model. This transplant procedure is feasible and we could demonstrate anti-tumour activity against lymphoma and breast cancer. 

Figure: Nearly every patient has a haploidentical donor (1 chromosome in common).

In the mouse model mice breast cancer and lymphoma could only be cured by using a donor transplantation. In case a syngeneic (syngeneic in inbred strains = autologous (self) in men) transplantation was performed, mice could never be cured. Since there is no immune effect in syngeneic transplantations , this proves that the immune system of the donor plays a crucial role in fighting the cancer!

Interestingly in haploidentical transplantations not only immune T cells might be relevant but also Natural Killer cells. We are presently analysing what cells do cause the anti-tumour effect in breast cancer.

In the clinic we finished a study on non-myeloablative transplantation in solid tumours. Though the method of non-myeloablative transplantation was successful with respect to donor engraftment there was still substantial toxicity. Unfortunately there was no long term effect in patients with solid tumours, including breast cancer.

Present research on transplantation program (started 2006)

One of the major limitations - in fact the only one - in clinical haploidentical transplantation is the high rate of infections, because of slow immune reconstitution after the conditioning and because of T cell depletion of the graft.

Most challenging would be if a transplant could be performed without a condition regimen, therefore preventing morbidity and mortality. Therefore we started a collaboration with the research group in Bergamo, Italy, to see if we can develop a cell based tolerance-inducing regimen in haploidentical transplantations. The scope of this program is to induce tolerance of the recipient against the donor to realise engraftment of the donor stem cells.

Also with the aim to restore immunity after transplantation we started a program on de novo T cell production from bone marrow stem cells (Funded by Senter-Novem; partners: Pharmacell, Riken Institute in Japan and Maia scientific in Belgium (2006-2009).

In this project we study if T cells with can be produced de novo, making use of bone marrow derived hematopoietic stem cells. For this an artificial thymus system is used. The expectation is that T cells can be made with antigen specific activity. These T cells could then be used for immune recovery after bone marrow stem cell transplantation. Also tumour specific T cells could be made.

Haploidentical tranplantations clinically

In 2005 and 2006 the first 3 haploidentical transplantations have been performed. Unfortunately, two of three patients died because of infections (in the published literature treatment related mortality is about 30 %). The anti-leukemia effect is however very good. None of the 3 patients showed any evidence of disease, and one patient seems to be cured more than one year after transplantation. This haploidentical transplantation program is based on the observation that Natural Killer Cells are relevant for the anti-tumour effects, especially in Acute Myeloid leukaemia. These cells seem to be far more effective than the immune T cells, that are thought to be the effector cells after HLA matched donor transplantation.

This observation induces a new paradigma in bone marrow stem cell transplantation and some haematologist expect that focusing on Natural Killer cell activity in donor stem cell transplantation will be the standard in a few years from now. This would mean for clinical practice that the now used HLA matched transplantation (only family transplants in Maastricht) will move to haploidentical transplantation. For patients this would mean a 2 fold higher change of finding an adequate donor in the family.

The haploidentical transplantation program is presently extended clinically for acute leukaemia and is in line with the preclinical research line. At present we do analyse if patients with other diseases, like multiple myeloma and breast cancer, might also profit from this new concept in cancer immunotherapy.
 

Selected publications

S Cloosen, EBM van Leeuwen, BLMG Senden-Gijsbers, EBH Oving, JW Gratama, WTV Germeraad, and GMJ Bos.
Different mucin-1 glycoforms are expressed on multiple myeloma and acute myeloid leukemia cells.
Br J Hematology 2006 135:513-516

VanClee Ariana, Michel van Gelder, Harry schouten, Gerard MJ Bos.
Murine mammary carcinoma can be cured in a model of non-myeloablative haploidentical stem cell stransplantation.
Bone Marrow Transplant. 2006 Jun;37(11):1043?9 

EBM van Leeuwen, S Cloosen, BLMG Senden-Gijsbers, WTV Germeraad and GMJ Bos. Transduction with a fiber-modified adenoviral vector is superior to non-viral nucleofection to express tumour-associated antigen Mucin-1 in human dendritic cells.
Journal of Immunotherapy. Cytotherapy 2006 Feb; 8 (1): 24-35

EBM van Leeuwen, S Cloosen, BLMG Senden-Gijsbers, U Mandel, H Clausen, JJ García-Vallejo, WTV Germeraad and GMJ Bos.
Expression of aberrantly glycosylated tumour Mucin-1 on human dendritic cells after transduction with a fiber-modified adenoviral vector.
Cytotherapy 2006 Feb; 8 (1): 36-46

Research group

Dr. G. Bos, project leader
Prof.dr. H. Schouten
Dr. M. van Gelder
Dr. W. Germeraad
Dr. P. Hupperets 

Post-doctoral fellows

Dr. A. Vanclee
Dr. S. Cloosen
Dr. B. Meek
Dr. J. Vanderlocht 

PhD students

M. Huls
J. v.d. Elssen
P. Frijns 

Technicians

B. Senden 

Students

P. Frings
M. Head
J. Van Elssen
J. Bogie
K. Hoeben

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In MAASTRO, patients are included in studies that, preferentially, are in line with the research themes of the MAASTRO clinic, MAASTRO lab and GROW. In order to maximise the proportion of patients that enter into clinical trials, a strategy was made to make ensure that patients are asked to participate within the most suitable study for them. In 2007, 28.3 % of all new patients were enrolled in biobank clinical trials and 6.8% in therapeutic trials. This is well above the European average of 3% or less.

In 2006 we started a major project, "Computer-Assisted-Theragnostic" with Siemens Medical. Our objective is to create Prediction Models of survival and complications for various pathologies and treatments. Ultimately, this will allow us to implement a strategy of individualized treatment based on objective data. We are setting up a prospective database allowing us to collect anonymously, a large amount of data from all the treated patients. Machine learning techniques and advanced statistical methods will be used to handle missing data to improve the methodology. A prototype for lung cancer has already been presented in Philadelphia at the ASTRO meeting.

One of our papers attracted significant attention from the scientific community (De Ruysscher et al. JCO 2007). The objective was to identify time factors for combined chemotherapy and radiotherapy predictive for long-term survival of patients with limited-disease small-cell lung cancer (LD-SCLC). Using meta-analysis methodology to compare results amongst trials, the influence of the timing of chest radiation and the start of any treatment until the end of radiotherapy (SER) on local tumour control, survival, and esophagitis was analyzed. We concluded that a short time between the first day of chemotherapy and the last day of chest radiotherapy is associated with improved survival in LD-SCLC patients. The novel parameter SER, which takes into account accelerated proliferation of tumour clonogens during both radiotherapy and chemotherapy, may facilitate a more rational design of combined-modality treatment in rapidly proliferating tumours.

In the field of physics, our main research concern the use of (4D)-CTPET simulation in lung cancer and the investigation of a pre-treatment and in-vivo dose verification procedure based on the use of an Electronic Portal Imaging Device (EPID) for all non-palliative patient treatments. This approach is named Dose Guided radiotherapy (DGRT). With DGRT, geometric and dosimetric radiation parameter values were verified for each individual patient, thus eliminating dose delivery errors caused by erroneous data transfer, bad functioning of the linear accelerator and patient related delivery errors Further improvement using 3D dosimetry is under investigation.

Selected publications

De Ruysscher D, Pijls-Johannesma M, Bentzen SM, Minken A, Wanders R, Lutgens L, Hochstenbag M, Boersma L, Wouters B, Lammering G, Vansteenkiste J, Lambin P.
Time between the first day of chemotherapy and the last day of chest radiation is the most important predictor of survival in limited-disease small-cell lung cancer.
J Clin Oncol. 2006 Mar 1;24(7):1057-63. I.F. 11.810 (Paper published with an Editorial). 

G. Bosmans, A. van Baardwijk, A. Dekker, M. Öllers, L. Boersma, A. Minken, P. Lambin, D. De Ruysscher.
Intra-patient variability of tumour volume and tumour motion during conventionally fractionated radiotherapy for locally advanced non-small cell lung cancer. A Prospective Clinical Study.
Int J Radiat Oncol Biol Phys 2006 Nov 1;66(3):748-53, I.F. 4.556

Baumert BG, Rutten I., Dehing-Oberije C, Twijnstra A., Dirkx MJM, Debougnoux-Huppertz MTL, Lambin P, Kubat B.
A pathology-based substrate for target definition in radiosurgery of brain metastases.
Int. J. Radiation Oncology Biol. Phys. 2006 Sep 1;66(1):187-94, I.F. 4.556

Figure 1: The survival at 5 years of patients with Small Cell Lung Cancer included in randomized trials related to the Start of any treatment until the end of Radiotherapy (SER). Each dot represent one arm of a randomized trial (De Ruysscher et al. JCO 2007).

Research group

Dr. D. de Ruysscher, project leader
Prof.dr. P. Lambin
Dr A. Dekker
Prof.dr. B. Wouters
Dr. L. Boersma
Dr. G. Lammering
Dr. B. Baumert
Bas Nijsten 

Post-doctoral fellows

Michel Oellers

PhD students

Dr. A. van Baardwijk
Dr. G. Bosmans
Mr H. Aerts
W. van Elmpt.
B. Nijsten 

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Molecular and Clinical Imaging

In order to individualize radiation therapy, our research has focused on imaging of different biologic tumour characteristics, like glucose metabolism, hypoxia and EGFR expression. Visualization of the biological characteristics of the different parts of the tumour using different tracers could result in guidance of delivered radiation or drug doses.

A. Clinical part

Positron emission tomography (PET) scans, mainly using 18 F-fluorodeoxyglucose (FDG) as a tracer, is currently widely accepted as a diagnostic tool in oncology. PET is used to evaluated staging and to define the target volume in radiation treatment planning in order to evaluate treatment response. We focused on issues concerning the role of PET in target volume delineation, both for primary tumor and regional lymph nodes (van Baardwijk et al. 2006).

We investigated for locally advanced non–small-cell lung cancer (n=23) the changes in tumor volume, motion, and breathing frequency during a radiotherapy course using CT-PET and RC-CT scanning before and after treatment. A striking heterogeneity of tumor volume changes was observed at all time points, but no significant changes in average tumor motion or breathing frequencies were observed during treatment (fig1) (Bosmans et al. 2006). This underscores the need for repeated imaging during the course of radiotherapy. However, the changes in tumor motion are small, which indicates that RC-CT does not appear to be necessary (Nagel et al. 2006, Bosmans et al, 2006).

B. Preclinical part

Besides PET, we used also fluorescent imaging to evaluate hypoxia in solid tumors. This was done using the Salmonella bacteria, where we followed fluorescent reporter gene expression driven off a hypoxia inducible promoter. The fluorescent signals correlated well with the amount of hypoxia (Mengesha, Dubois et al. 2006).

Recently, we also investigated the binding conditions for a fluorescent labeled sulfonamide against the hypoxia surrogate marker CA IX. Both in vitro and in vivo results indicate accumulation of the sulfonamide upon hypoxia exposure, indicating the possibility of non-invasive imaging of hypoxia trough its surrogate marker CA IX

Besides imaging of hypoxia of glucose metabolism, we investigated the possibility of imaging EGFR expression using its antibody Cetuximab, which we labeled with the radio-isotope Zirconium-89. In vivo µPET studies demonstrated clear uptake in an EGFR positive tumor (fig2) and this was confirmed by histopathology.

Selected publications

Nagel, C.C., Bosmans, G., Dekker, A.L., Ollers, M.C., De Ruysscher, D.K., Lambin, P., Minken, A.W., Lang, N. and Schafers, K.P.
Phased attenuation correction in respiration correlated computed tomography/positron emitted tomography.
Med Phys, 2006, 33(6):1840-1847

van Baardwijk, A., Baumert, B. G., Bosmans, G., van Kroonenburgh, M., Stroobants, S., Gregoire, V., Lambin, P. and De Ruysscher, D.
The current status of FDG-PET in tumour volume definition in radiotherapy treatment planning.
Cancer Treat Rev, 2006, 32(4):245-260

Bosmans, G., Buijsen, J., Dekker, A., Velders, M., Boersma, L., De Ruysscher, D., Minken, A. and Lambin, P.
An "in silico" clinical trial comparing free breathing, slow and respiration correlated computed tomography in lung cancer patients.
Radiother Oncol, 2006, 81(1):73-80

Bosmans, G., van Baardwijk, A., Dekker, A., Ollers, M., Boersma, L., Minken, A., Lambin, P. and De Ruysscher, D.
Intra-patient variability of tumor volume and tumor motion during conventionally fractionated radiotherapy for locally advanced non-small-cell lung cancer: A prospective clinical study.
Int J Radiat Oncol Biol Phys, 2006, 66(3):748-753

Mengesha A., Dubois L., Lambin P., Chiu R.K., Wouters B.G., Theys J.
Targeting of attenuated Salmonella to solid tumors by using hypoxia-inducible promoter elements.
Cancer Biol Ther 5, 2006: 1120-1128

Figure 1: Tumor volumes, as determined by computed tomography (CT), relative to the volume before treatment, were plotted vs. the dose. Thick black line is the average relative CT volume together with the standard deviation. Dotted lines represents patients in whom tumors increased more than 30%; dashed lines indicate patients in whom tumors decreased 30%.

Figure 2: (a) Western Blot to validate EGFR expression of EGFR positive cell line (A431) and negative cell line (T47D).
(b) A FACS saturation experiment has been done to analyze the specific binding of the Cetuximab Oregon Green 488 probe to the EGF receptor.
(c) Micro-PET image of a nude mouse, 48 hours after injection with Zirconium- Cetuximab, with an A431 tumor in the left flank, and a T47D tumor in the right flank.

Research group

Prof.dr. Philippe Lambin, project leader
Dr. Dirk De Ruysscher
Prof.dr. Bradly Wouters

Post-doctoral fellows

Dr. Guido Lammering
Dr. Andre Dekker

PhD students

Ludwig Dubois
Geert Bosmans
Angela van Baardwijk
Hugo Aerts

Technicians

Barry Jutten
Natasja Lieuwes

Students

Roel Straathof

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Rectal Cancer is a disease with many opportunities regarding clinical research. The current standard of practice consists of neoadjuvant preoperative radio (chemo-) therapy, which allows for translational biological and imaging studies with a present tumor in situ. All our currently ongoing research lines aim to individualize treatment by investigating new modern imaging tools before, during and after standard of care treatment practice as well as treatment with new drugs, e.g. biological modifiers during radiotherapy. Four interconnective research lines are currently ongoing:

1. The purpose of this prospective study is to determine the accuracy of USPIO-MRI for predicting of the nodal status in primary colorectal cancer patients. 40 Patients with primary rectal cancer underwent MRI after administration of Sinerem® contrast agent. All these patients were treated with TME surgery, after pre-operative radiotherapy. A radiologist prospectively recorded the amount, localization and signal-intensity of mesorectal and extramesorectal lymph nodes. Lesion by lesion analysis was performed with histology as the Gold Standard. The patient-based sensitivity, specificity, PPV and NPV were respectively 100%, 69%, 62% and 100%. The lesion by lesion analysis results in sensitivity, specificity, PPV and NPV of 95%, 95%, 65% and 99%, respectively. This prospective study suggests that USPIO-MRI is highly accurate in identifying N0 patients, allowing individual tailored treatment according to risks.

2. FDG-CT-PET after neoadjuvant chemoradiation of locally advanced rectal cancer

To assess the accuracy of post chemoradiation 18F-deoxyglucose (FDG)-CT-PET for the prediction of tumor downstaging and invasion of the mesorectal fascia. An abdominal radiologist and radiotherapist both experienced in CT-PET imaging retrospectively evaluated pre and post CT-PET images. Results are pending.

3. Determination of the predictive value of repetitive FDG-PET-CT scans and blood proteins for the prognosis of patients with rectal cancer

To investigate the evolution of the FDG uptake and the tumour characteristics determined in the plasma of patients with rectal cancer during and after radiotherapy or combined radiotherapy and chemotherapy. Study hypothesis: The changes of the FDG uptake of the primary tumour and the evolution of key tumour characteristics during radiotherapy alone or in combination with chemotherapy will be predictive for the outcome. Endpoints: Prediction of the tumour response shortly after radiotherapy by a PET-CT scan and blood samples for the patients receiving short-course radiotherapy alone. Prediction of the tumour response 6-8 weeks after radiochemotherapy treatment by PET-CT scans and by blood samples during concurrent radiotherapy and chemotherapy.

4. The combination of molecular targeted drugs with radiotherapy in rectal cancer - towards individualized therapy

We will start two new phase I/II phase clinical trials. High quality translational research will test the activity of the drugs in modulating the microenvironment and tumor cellular responses and will identify predictors of activity. 3a. Rapamycin (mTor inhibitor) will be administered before and during preoperative short-term RT (5 x 5Gy) in operable rectal cancer. 3b. Nelfinavir (Akt inhibitor) will be administered before and during preoperative radiochemotherapy (28 x 1.8 Gy + Capecitabine daily) in locally advanced rectal cancer.The optimal dose found in phase I will be administered in phase II. The primary endpoint of Rapamycin activity will be the tumor blood flow assessed by dynamic contrast-enhanced (DCE-) MRI.The primary endpoint of Nelfinavir activity will be the rate of pathological complete remission (pCR) at the time of surgery.

Funding

2006 - 2010. Profileringsfond, University Hospital Maastricht, phase I-II

clinical trial testing Rapamycin (Sirolimus) in combination with preoperative

radiotherapy in operable rectal cancer. 110.000 Euro

Selected publications

Baeten CI, Castermans K, Lammering G, Hillen F, Wouters BG, Hillen HF, Griffioen AW, Baeten CG.
Effects of radiotherapy and chemotherapy on angiogenesis and leukocyte infiltration in rectal cancer.
Int J Radiat Oncol Biol Phys. 2006 Nov 15;66(4):1219-1227.

Wolberink SV, Beets-Tan RG, Nagtegaal ID, Wiggers T.
Preoperative assessment of the circumferential margin in rectal cancer is more informative in treatment planning than the T stage.
Tech Coloproctol. 2006 Oct;10(3):171-6. 

 

Figure: False positive PET-CT interpretation of a circumferential resection margin invasion after radiochemotherapy: the histology reveals an inflammatory reaction into vagina wall, but not a tumoral invasion.

Research group

Dr. R.G.H. Beets-Tan, project leader
Dr. G. Lammering
Dr. G.L. Beets
Prof.dr. P. Lambin
Prof.dr. A. de Bruine
Prof.dr. BG. Wouters
Prof.dr. J. Teulen
Prof.dr. AW. Griffioen
Prof.dr. CG. Baeten 

Post-doctoral fellows

Dr. M. Oellers
Dr. R. Jansen
Dr. M. van Engeland
Dr. M. van Kroonenburgh 

PhD students

R. Vliegen
S.M.E. Engelen
M.J. Lahaye
J. Buijsen
B. Vanhouten
H. Aerts
CI. Baeten 

Technicians

J. van den Boogaard
N. Lieuwes 

Students

M. Janssen 

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