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Featured researches published by Guus Hart.


Gastroenterology | 1997

Histological grading in gastric lymphoma: Pretreatment criteria and clinical relevance

D. de Jong; Henk Boot; P. Van Heerde; Guus Hart; Babs G. Taal

BACKGROUND & AIMS Stomach-conserving therapy in primary gastric non-Hodgkins lymphoma (mucosa-associated lymphoid tissue [MALT]-NHL) is increasingly gaining importance as an alternative to surgery. As a consequence, surgical pathologists have to define histological criteria in pretreatment endoscopic biopsy specimen samples not only to make the diagnosis but also to recognize minor tumor components that may infer a significantly adverse impact on prognosis. The aim of this study was to define histological criteria for clinically significant tumor progression in pretreatment endoscopic biopsy specimens. METHODS In a consecutive series of 106 patients with gastric MALT-NHL, the prognostic impact of large cell components was assessed by semiquantitative analysis of clusters and diffusely intermingled malignant blasts. RESULTS In low-grade MALT-NHL, a category with a diffuse large cell component of 1%-10% with or without nonconfluent clusters of blasts could be separated with a significantly worse prognosis (10-year disease-specific survival, 90% vs. 75%). No clinical parameters of known prognostic significance could account for this difference. CONCLUSIONS It is possible to define criteria in endoscopic biopsy specimens to recognize clinically relevant tumor progression. To serve as a guideline in the choice of treatment, these criteria should be validated prospectively in future clinical trials.


European Journal of Cancer | 1981

Observations on Pulmonary Metastases in Patients After Single Doses and Multiple Fractions of Fast Neutrons and Cobalt-60 Gamma Rays

Jan J. Battermann; Klaas Breur; Guus Hart; Henny A. van Peperzeel

Abstract Pulmonary metastases have been irradiated with single and fractionated doses of fast neutrons and cobalt-60 gamma rays. The response to radiation was measured on volume changes of the lesions and thus RBE values could be derived. A correlation was found between grading of the tumour and volume doubling time and also between RBE and volume doubling time. This suggests an advantage for high LET radiation of slowly growing, well differentiated tumours. Furthermore the RBE for multiple fractions tends to be higher than for single doses. Calculation of the N exponent of the Ellis formula indicated that hardly any shoulder exists when neutrons are applied.


Cancer | 1983

The value of postoperative radiotherapy as an adjuvant to radical neck dissection

Harry Bartelink; Klaas Breur; Guus Hart; Bert Annyas; Emil van Slooten; Gordon B. Snow

In this study the results of combined radiotherapy and surgery are compared with the results of surgery alone in patients with neck node metastases from squamous cell carcinomas of the head and neck region. Postoperative radiotherapy decreases the recurrence rate in the neck, especially in cases with histologically established extranodal spread. Results of preoperative radiotherapy were similar to those of irradiation after surgery. Postoperative radiotherapy is favored, because it allows a selection of patients for extra treatment on the base of prognostic information, provided by the histologic characteristics of the neck dissection specimen.


International Journal of Radiation Oncology Biology Physics | 1985

Adjuvant chemo- and hormonal therapy in locally advanced breast cancer: a randomized clinical study.

C. Schaake-Koning; Els Hamersma Van Der Linden; Guus Hart; Evert Engelsman

UNLABELLED Between 1977 and 1980, 118 breast cancer patients with locally advanced disease, T3B-4, any N, M0 or T1-3, tumor positive axillary apex biopsy, were randomized to one of three arms: I: radiotherapy (RT) to the breast and adjacent lymph node areas; II: RT followed by 12 cycles of cyclophosphamide, methotrexate, 5 fluorouracil (CMF) and tamoxifen during the chemotherapy period; III: 2 cycles of adriamycin and vincristine (AV), alternated with 2 cycles of CMF, then RT, followed by another 4 cycles of AV, alternated with 4 CMF; tamoxifen during the entire treatment period. The median follow-up period was 5 1/2 years. The adjuvant chemo- and hormonal therapy did not improve the overall survival; the 5-year survival was 37% for all three treatment arms. There was no statistically significant difference in RFS between the three modalities, nor when arm I was compared to arm II and III together, p = 0.11. Local recurrence (LR) was observed in 24 of the 86 patients (28%) who had reached complete remission (CR). LR was not statistically different over the three treatment arms. In 18 of the 24 patients with LR, distant metastases appeared within a few months from the local recurrence. In arm III, the CR rate after 4 cycles AV plus CMF and RT hardly changed after another 8 cycles of chemotherapy. The menopausal status did not influence the treatment results. Dose reduction in more than 4 cycles of chemotherapy was accompanied by better results, p = 0.04. IN CONCLUSION adjuvant chemo- and hormonal therapy did not improve RFS and overall survival. These findings do not support the routine use of adjuvant chemo- and endocrine therapy for inoperable breast cancer.


Journal of Clinical Oncology | 1999

Effect of radiotherapy and chemotherapy on pulmonary function after treatment for breast cancer and lymphoma: A follow-up study.

Jacqueline C.M. Theuws; Sara H. Muller; Yvette Seppenwoolde; Stefan L.S. Kwa; L.J. Boersma; Guus Hart; Paul Baas; Joos V. Lebesque

PURPOSE To determine the changes in pulmonary function tests (PFTs) 0 to 48 months after treatment for breast cancer and lymphoma. PATIENTS AND METHODS The alveolar volume (V(A)), vital capacity, forced expiratory volume in 1 second, and corrected transfer factor of carbon monoxide (T(L,COc)) were measured in 69 breast cancer and 41 lymphoma patients before treatment and 3, 18, and 48 months after treatment with radiotherapy alone or radiotherapy in combination with chemotherapy (mechlorethamine, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, vinblastine; cyclophosphamide, epidoxorubicin, fluorouracil; cyclophosphamide, thiotepa, carboplatin; cyclophosphamide, methotrexate, fluorouracil). The three-dimensional dose distribution in the lung of each patient was converted to the mean lung dose. Statistical analysis was used to evaluate the changes in PFT values over time in relation to age, sex, smoking, chemotherapy, and the mean lung dose. RESULTS After an initial reduction in PFT values at 3 months, significant recovery was seen at 18 months for all patients. Thereafter, no further improvement could be demonstrated. Reductions in spirometry values and V(A) were related to the mean lung dose only (0.9% per Gy at 3 months and 0.4% per Gy mean dose at 18 months). T(L,COc) decreased 1. 1% per Gy mean dose and additionally decreased 6% when chemotherapy was given after radiotherapy. Chemotherapy administered before radiotherapy reduced baseline T(L,COc) values by 8% to 21%. All patients showed an improvement of 5% at 18 months. CONCLUSION On the basis of the mean lung dose and the chemotherapy regimen, the changes in PFT values can be estimated before treatment within 10% of the values actually observed in 72% to 85% of our patients with healthy lungs.


Journal of The American College of Surgeons | 1999

Relation between limb toxicity and treatment outcomes after isolated limb perfusion for recurrent melanoma.

Bart C. Vrouenraets; Guus Hart; Alexander M.M. Eggermont; J. M. Klaase; Bert N. van Geel; Omgo E. Nieweg; Bin B. R. Kroon

BACKGROUND The optimal toxic reaction of the normal tissues in perfused limbs after isolated limb perfusion (ILP) is unknown. Theoretically, more severe limb toxicity could reflect a concomitant increased toxic effect to the tumor and improved outcomes. We determined whether there is a relation between limb toxicity and treatment outcomes after ILP for recurrent limb melanoma. STUDY DESIGN Among 252 patients with recurrent melanoma of the limbs, treatment outcomes in 192 patients (76%) with no or mild acute limb toxicity were compared with those in 60 (24%) with more severe reactions. Multivariate analysis was used to identify prognostic factors for complete response, limb recurrence-free interval, and survival. RESULTS Among 112 patients with measurable disease, 65 patients (58%) had a complete response and 27 (42%) experienced a relapse in the perfused limb. For complete response, uninvolved regional lymph nodes (p = 0.0025) and ILP using tumor necrosis factor-alpha (p = 0.0076) appeared to be favorable prognostic factors in multivariate analysis. There was no evidence of a relation between limb toxicity and complete response either in univariate (p = 0.16) or multivariate analysis (p = 0.46). For limb recurrent-free interval, only the number of lesions was a significant prognostic factor (p = 0.047); limb toxicity was not (p = 0.095). In 140 patients with recurrent melanoma excised before or at the moment of ILP, independent prognostic factors for survival were gender, the number of positive nodes, and stage of disease. There was no relation between limb toxicity and survival in either univariate (p = 0.53) or multivariate analysis (p = 0.94). Forty-eight (34%) of the 140 patients had a relapse in the perfused limb. No prognostic factors for limb recurrent-free interval could be identified; limb toxicity was not related to relapse time in univariate or multivariate analyses (p = 0.16 and p = 0.14, respectively). CONCLUSIONS More severe acute limb toxicity is not associated with improved outcomes. One should aim at grade II toxicity (slight erythema or edema, compatible with complete recovery) at the most to increase the therapeutic ratio of ILP.


Radiotherapy and Oncology | 2011

Nomogram to predict ipsilateral breast relapse based on pathology review from the EORTC 22881-10882 boost versus no boost trial

Erik van Werkhoven; Guus Hart; Harm van Tinteren; Paula H.M. Elkhuizen; Laurence Collette; Philip Poortmans; Harry Bartelink

BACKGROUND AND PURPOSE The EORTC 22881-10882 trial showed that for patients treated with breast conserving therapy (BCT), a 16Gy boost dose significantly improved local control, but increased the risk of breast fibrosis. A model to estimate the risk of ipsilateral breast relapse (IBR) already exists, but now a model has been developed which takes boost treatment into account and is based on centrally reviewed pathology. MATERIALS AND METHODS A Cox model was developed based on central pathology review data and clinical data of 1603 patients from the EORTC 22881-10882 trial with a median follow-up of 11.5years. From a predefined set of variables, predictors with a maximal effect on 10-year IBR rate >4% were retained in the model. Bootstrap re-sampling was used to assess model calibration and discrimination. The results are presented in the form of a nomogram. RESULTS Apart from young age and no boost, presence of DCIS adjacent to the invasive tumor was associated with increased risk of IBR (HR 1.96, p=0.001). Patients with high grade invasive tumors were younger than patients with low/intermediate grade (p<0.0001). The nomogram includes histologic grade, DCIS, tumor diameter, age, tamoxifen, chemotherapy, and boost with a concordance probability estimate of 0.68. CONCLUSIONS The nomogram for predicting IBR 10years after BCT includes seven factors, with young age, presence of DCIS and boost treatment as the most dominant factors. The nomogram estimates IBR and confirms the importance of a boost dose. Combined with a model to predict fibrosis published previously, the nomogram presented here may assist in decision making for individual patients.


The Journal of Pathology | 2001

Histological and immunological parameters to predict treatment outcome of Helicobacter pylori eradication in low-grade gastric MALT lymphoma.

Daphne de Jong; Florry A. Vyth-Dreese; Trees A. M. Dellemijn; Natascha Verra; Agnès Ruskone-Fourmestraux; Anne Lavergne-Slove; Guus Hart; Henk Boot

Helicobacter pylori eradication is generally accepted as the first choice of treatment for stage IE low‐grade gastric MALT lymphoma (mucosa‐associated lymphoid tissue‐type lymphoma). Treatment failure may be attributed to the extent of the disease and to progression into an antigen‐independent phase. This study assessed the value of morphological grading and the expression of the co‐stimulatory markers CD40, CD80 and CD86 and their ligands to predict clinical outcome in 23 consecutive low‐grade MALT lymphoma patients treated with H. pylori eradication. Complete regression was achieved in 13/23 patients (56%), partial regression in two (9%), and no response in eight (35%). Histological grading was highly predictive of clinical response, especially in stage IE1 patients, with complete remissions in 10/12 tumours with purely low‐grade (type A) morphology and 1/8 tumours with increased numbers of blasts (type B) (p=0.0046) and was related to the expression of costimulatory markers (p=0.0061). Moreover, CD86 as a single marker proved to be of predictive value for treatment outcome (p=0.0086). These results suggest that morphological grading and immunological criteria can be defined to recognize the transition into the antigen‐independent phase of gastric MALT‐NHL. In addition to clinical stage, these critera may in future serve as a practical pathological guide to the choice of therapy. Copyright


International Journal of Radiation Oncology Biology Physics | 1982

Radiotherapy of lymph node metastases in patients with squamous cell carcinoma of the head and neck region

Harry Bartelink; Klaas Breur; Guus Hart

The results of radiotherapy alone in 233 patients with lymph node metastases of squamous cell carcinoma in the head and neck region were examined. It appeared that the recurrence rate in the neck was mainly related to: localization of the primary tumor; the recurrence of the primary tumor; the radiation dose; and the presence of a residual palpable tumor mass in the neck 6 weeks after radiation. The optimum radiation dose was about 2000 ret. An isoeffect curve was calculated, which differed only slightly with the nominal standard dose (NSD) formula. Elective irradiation of the contralateral neck appeared to diminish the outgrowth of neck node metastases at the side. Changes in the radiation treatment in the last treatment period, such as a higher radiation dose and a larger treatment area, resulted in a lower recurrence rate for the neck node metastases, and also in a higher survival rate.


American Journal of Surgery | 1994

Patient- and treatment-related factors associated with acute regional toxicity after isolated perfusion for melanoma of the extremities

J. M. Klaase; Bin B. R. Kroon; Bert N. van Geel; Alexander M.M. Eggermont; H. Franklin; Guus Hart

In order to gain some insight into the cause of acute regional toxicity after isolated perfusion using melphalan, 15 patient-related and perfusion-technique-related factors were tested in a logistic regression model. Acute toxicity was graded according to Wieberdinks grading system. In a group of 425 patients, 362 (85%) encountered no or slight toxicity with a grade I or II reaction, and 63 (15%) patients encountered more severe toxicity with a grade III, IV, or V reaction. Most patients were treated with a standard dose of 10 or 13 mg melphalan per liter of perfused tissue for leg and arm perfusions, respectively. Factors associated with a more severe toxicity reaction proved to be tissue temperatures of 40 degrees C or higher, female gender, a deterioration of the gas values of the venous perfusate during perfusion, and perfusion at a proximal level of isolation. Consideration of these prognostic factors may lead to a further decrease of acute regional toxicity in perfusion.

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Harry Bartelink

Netherlands Cancer Institute

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Erik van Werkhoven

Netherlands Cancer Institute

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Marjan Ruevekamp

Netherlands Cancer Institute

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Bin B. R. Kroon

Netherlands Cancer Institute

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Joos V. Lebesque

Netherlands Cancer Institute

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Klaas Breur

Netherlands Cancer Institute

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Peter W. de Graaf

Netherlands Cancer Institute

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Philip Poortmans

Radboud University Nijmegen

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Laurence Collette

European Organisation for Research and Treatment of Cancer

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