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Dive into the research topics where B.J. Slotman is active.

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Featured researches published by B.J. Slotman.


Journal of Clinical Oncology | 2004

The Additional Value of Chemotherapy to Radiotherapy in Locally Advanced Nasopharyngeal Carcinoma: A Meta-Analysis of the Published Literature

Johannes A. Langendijk; C.R. Leemans; Jan Buter; J Berkhof; B.J. Slotman

PURPOSEnThe purpose of this meta-analysis was to determine the additional value of neoadjuvant, concurrent, and/or adjuvant chemotherapy to radiation in the treatment of locally advanced nasopharyngeal carcinoma (NPC) with regard to the overall survival (OS) and the incidence of local-regional recurrences (LRR) and distant metastases (DM).nnnPATIENTS AND METHODSnTo be eligible, full published studies had to deal with biopsy-proven NPC and have patients randomly assigned to receive conventional radiotherapy (66 to 70 Gy in 7 weeks) or radiotherapy combined with chemotherapy.nnnRESULTSnTen randomized clinical studies were identified, including 2,450 patients. The pooled hazard ratio (HR) of death for all studies was 0.82 (95% CI, 0.71 to 0.95; P = .01) corresponding to an absolute survival benefit of 4% after 5 years. Three categories of trials were defined according to the sequence of chemotherapy, including neoadjuvant chemotherapy, at least concomitant chemoradiotherapy, and adjuvant chemotherapy. A significant interaction term (P = .02) was found among these three categories. The largest effect was found for concomitant chemotherapy, with a pooled HR of 0.48 (95% CI, 0.32 to 0.72), which corresponds to a survival benefit of 20% after 5 years. Comparable results were found for the incidence of LRR and DM.nnnCONCLUSIONnThe results of this study indicate that concomitant chemotherapy in addition to radiation is probably the most effective way to improve OS in NPC.


European Journal of Cancer | 2002

Gemcitabine-radiotherapy in patients with locally advanced pancreatic cancer

S. M. de Lange; C.J. van Groeningen; Otto W. M. Meijer; Miguel A. Cuesta; Johannes A. Langendijk; J.M.G.H. van Riel; H.M. Pinedo; Godefridus J. Peters; Sybren Meijer; B.J. Slotman; G. Giaccone

A feasibility study was performed to assess the toxicity and efficacy of a combination of gemcitabine-radiotherapy in patients with locally advanced pancreatic cancer (LAPC). 24 patients (15 females and 9 males) with measurable LAPC were included; the median age of the patients was 63 years (range 39-74 years). The performance status ranged from 0 to 2. Gemcitabine was administered at a dose of 300 mg/m(2), concurrent with radiotherapy, three fractions of 8 Gy, on days 1, 8 and 15. When compliance allowed, gemcitabine alone was continued thereafter, at 1000 mg/m(2), weekly times 3, every 4 weeks, depending on the response and toxicity. All patients were evaluable for toxicity and response. The objective response rate was 29.2% (1 complete remission+6 partial remissions); 12 patients had stable disease. However, 2 of the radiological partial remissions were shown to be complete remissions by pathology assessment. Median duration of response was 3 months (range 1-35+months). Median time to progression was 7 months (range 2-37+months). Median survival was 10 months (range 3-37+months). Dose reduction or omission of gemcitabine was necessary in 10 patients. Non-haematological toxicity consisted of 87.5% nausea and vomiting grade I-II, diarrhoea 54%, ulceration in stomach and duodenum 37.5% (20.8% ulceration with bleeding); 1 patient developed a fistula between the duodenum and aorta, 5 months after treatment. Anaemia grade III-IV was observed in 8.3% of the patients. Neutropenia grade III-IV was observed in 8.3%, thrombocytopenia grades III-IV in 16.7%. In 1 patient who underwent resection postchemoradiation, no viable tumour cells were found. In addition, in the patient who suddenly died of a fistula between the duodenum and aorta, no viable tumour cells were detectable at autopsy. Although the toxicity of this treatment was occasionally severe, the response and survival are encouraging and warrant further studies of this combination.


Gynecologic Oncology | 1989

Importance of steroid receptors and aromatase activity in the prognosis of ovarian cancer: High tumor progesterone receptor levels correlate with longer survival

B.J. Slotman; Radka Kühnel; B.Ramanath Rao; Gerard H. Dijkhuizen; Jan de Graaff; Johannes G. Stolk

The presence of steroid receptors (82 tumors) and aromatase activity (39 tumors) in ovarian carcinomas was correlated with patient survival. No statistically significant correlation was found between the presence or absence of estrogen receptors (ER, 56.1%), progesterone receptors (PR, 57.3%), androgen receptors (AR, 91.5%), or aromatase activity (33.3%) and survival. However, high levels of PR were associated with better survival (P less than 0.05). Furthermore, there was a tendency for patients with advanced disease and PR-positive tumors to have better survival than those with advanced disease and PR-negative tumors (P = 0.13). Patients with tumors that did not contain any of the receptors and those in which ER and AR were absent, or in which PR and AR were absent, had poor survival. It is concluded that receptor status, especially of PR, may be of prognostic importance and that status of receptors and aromatase activity may become useful in selecting ovarian cancer patients for endocrine therapy.


Radiotherapy and Oncology | 2014

Radiotherapy staffing in the European countries: Final results from the ESTRO-HERO survey

Yolande Lievens; Mary Coffey; N. Defourney; Peter Dunscombe; Josep M. Borràs; B.J. Slotman; Julian Malicki; Marta Bogusz; Chiara Gasparotto; Cai Grau

BACKGROUNDnThe ESTRO Health Economics in Radiation Oncology (HERO) project has the overall aim to develop a knowledge base of the provision of radiotherapy in Europe and build a model for health economic evaluation of radiation treatments at the European level. The first milestone was to assess the availability of radiotherapy resources within Europe. This paper presents the personnel data collected in the ESTRO HERO database.nnnMATERIALS AND METHODSnAn 84-item questionnaire was sent out to European countries, through their national scientific and professional radiotherapy societies. The current report includes a detailed analysis of radiotherapy staffing (questionnaire items 47-60), analysed in relation to the annual number of treatment courses and the socio-economic status of the countries. The analysis was conducted between February and July 2014, and is based on validated responses from 24 of the 40 European countries defined by the European Cancer Observatory (ECO).nnnRESULTSnA large variation between countries was found for most parameters studied. Averages and ranges for personnel numbers per million inhabitants are 12.8 (2.5-30.9) for radiation oncologists, 7.6 (0-19.7) for medical physicists, 3.5 (0-12.6) for dosimetrists, 26.6 (1.9-78) for RTTs and 14.8 (0.4-61.0) for radiotherapy nurses. The combined average for physicists and dosimetrists is 9.8 per million inhabitants and 36.9 for RTT and nurses. Radiation oncologists on average treat 208.9 courses per year (range: 99.9-348.8), physicists and dosimetrists conjointly treat 303.3 courses (range: 85-757.7) and RTT and nurses 76.8 (range: 25.7-156.8). In countries with higher GNI per capita, all personnel categories treat fewer courses per annum than in less affluent countries. This relationship is most evident for RTTs and nurses. Different clusters of countries can be distinguished on the basis of available personnel resources and socio-economic status.nnnCONCLUSIONSnThe average personnel figures in Europe are now consistent with, or even more favourable than the QUARTS recommendations, probably reflecting a combination of better availability as such, in parallel with the current use of more complex treatments than a decade ago. A considerable variation in available personnel and delivered courses per year however persists among the highest and lowest staffing levels. This not only reflects the variation in cancer incidence and socio-economic determinants, but also the stage in technology adoption along with treatment complexity and the different professional roles and responsibilities within each country. Our data underpin the need for accurate prediction models and long-term education and training programmes.


Radiotherapy and Oncology | 2001

The efficacy of Xialine® in patients with xerostomia resulting from radiotherapy for head and neck cancer: a pilot-study

Anke Petra Jellema; Hans Langendijk; Lester Bergenhenegouwen; Willy van der Reijden; Rene Leemans; Ludy Smeele; B.J. Slotman

Changes in subjective sensations due to xerostomia before and after administration of Xialine, a xanthan gum-based saliva substitute, were evaluated in 30 patients with radiation-induced xerostomia using the QLQ-H&N35. Xerostomia in general decreased with both Xialine and placebo to almost the same degree. A trend was seen for Xialine to improve problems with speech and senses.


Cancer | 1990

Survival of patients with ovarian cancer : apart from stage and grade, tumor progesterone receptor content is a prognostic indicator

B.J. Slotman; Jos J. P. Nauta; B. Ramanath Rao

Estrogen (ER), progesterone (PR), and androgen receptors (AR) were determined by saturation analysis in 100 cases of primary ovarian cancer and correlated with patient survival. The mean follow‐up period was 5.4 years (range, 4 to 6.5 years). Positivity for PR was associated with a significantly better survival rate (P < 0.05). A similar observation was made for AR (P < 0.05). Tumor ER content did not correlate with survival. Ten patients with tumors that had negative results for both PR and AR all died of the disease. In 91 cases of serous, endometrioid, and mucinous carcinomas, grade, stage, and tumor PR content, but not AR content, were identified as independent prognostic factors with the use of the Cox proportional hazards model. The relative risk of patients with PR‐negative tumors was 2.3 times higher than that of patients with tumors containing high (≥ 30 fmol/ mg) PR levels.


Radiotherapy and Oncology | 2017

Fast and robust online adaptive planning in stereotactic MR-guided adaptive radiation therapy (SMART) for pancreatic cancer

O. Bohoudi; A.M.E. Bruynzeel; Suresh Senan; J.P. Cuijpers; B.J. Slotman; F.J. Lagerwaard; M.A. Palacios

BACKGROUND AND PURPOSEnTo implement a robust and fast stereotactic MR-guided adaptive radiation therapy (SMART) online strategy in locally advanced pancreatic cancer (LAPC).nnnMATERIAL AND METHODSnSMART strategy for plan adaptation was implemented with the MRIdian system (ViewRay Inc.). At each fraction, OAR (re-)contouring is done within a distance of 3cm from the PTV surface. Online plan re-optimization is based on robust prediction of OAR dose and optimization objectives, obtained by building an artificial neural network (ANN). Proposed limited re-contouring strategy for plan adaptation (SMART3CM) is evaluated by comparing 50 previously delivered fractions against a standard (re-)planning method using full-scale OAR (re-)contouring (FULLOAR). Plan quality was assessed using PTV coverage (V95%, Dmean, D1cc) and institutional OAR constraints (e.g. V33Gy).nnnRESULTSnSMART3CM required a significant lower number of optimizations than FULLOAR (4 vs 18 on average) to generate a plan meeting all objectives and institutional OAR constraints. PTV coverage with both strategies was identical (mean V95%=89%). Adaptive plans with SMART3CM exhibited significant lower intermediate and high doses to all OARs than FULLOAR, which also failed in 36% of the cases to adhere to the V33Gy dose constraint.nnnCONCLUSIONSnSMART3CM approach for LAPC allows good OAR sparing and adequate target coverage while requiring only limited online (re-)contouring from clinicians.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 1988

Interferon-α in treatment of intraepithelial neoplasia of the lower genital tract: a case report

B.J. Slotman; Th.J.M. Helmerhorst; P.W. Wijermans; J.J. Calame

Abstract A patient with persistent intraepithelial neoplasia of the vulva, vagina and cervix was treated with subcutaneous injections of interferon-α-2b. Previous surgical and laser procedures had failed. HPV subtype 16 was found in biopsies from all sites and an immunological screening was performed before and after therapy. Histologically proven regression of the intraepithelial neoplasia was seen at all sites, with a complete remission of the cervical lesions. The role of interferon in treatment of intraepithelial neoplasia is discussed.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 1991

Correlation between nuclear DNA content and steroid receptor status in ovarian cancer

B.J. Slotman; J.P.A. Baak; B. Ramanath Rao

The nuclear DNA content of 47 malignant epithelial ovarian tumours and five ovarian tumours of borderline malignancy was correlated with estrogen (ER), progesterone (PR) and androgen receptor (AR) status. Aneuploidy was observed in 60% of the malignant tumours. The DNA index of poorly differentiated tumours was higher than that of well differentiated tumours (P less than 0.05). Ploidy did not correlate with histological type, stage of disease and ER content. Of the diploid tumours, 74% was PR-positive, in contrast to 36% of the aneuploid tumours (P less than 0.05). In addition, 89% of the diploid tumours had high AR levels (greater than or equal to 30 fmol/mg cytosol protein), in contrast to only 54% of the aneuploid tumours (P less than 0.05). These observations strengthen our previous findings on the prognostic importance of PR and also suggest that androgens may have a role in ovarian cancer.


Annals of Oncology | 2011

Postoperative elective nodal irradiation for squamous cell carcinoma of the head and neck: outcome and prognostic factors for regional recurrence

Marije R. Vergeer; P. Doornaert; R. de Bree; C.R. Leemans; B.J. Slotman; Johannes A. Langendijk

BACKGROUNDnThis study describes the results of elective irradiation in the N0 neck and tries to identify prognostic factors for regional recurrence.nnnMATERIALS AND METHODSnBetween 1985 and 2000, 785 cN0 or pN0 necks were treated with elective nodal irradiation in 619 head and neck squamous cell carcinoma patients.nnnRESULTSnRegional control at 3 years was 94% in the cN0 (nondissected) neck compared with 97% in the pN0 (dissected) neck and 90% in the ipsilateral compared with 96% in the contralateral neck (P = 0.08 and P = 0.006, respectively). Regional control in the ipsilateral cN0 neck was 78% compared with 96% in the contralateral cN0 neck. Surgical margin of the primary tumor was an additional prognostic factor in all N0 and pN0 necks.nnnCONCLUSIONSnNeck control rates in electively irradiated N0 necks were excellent. Regional control was worse in the cN0 neck compared with the pN0 neck and in the ipsilateral neck compared with the contralateral side. Additionally, in case of positive surgical margins of the primary tumor, elective nodal irradiation should be applied, even in case of a pN0 neck.

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Max Dahele

VU University Medical Center

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S. Senan

VU University Medical Center

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Johannes A. Langendijk

University Medical Center Groningen

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P. Doornaert

VU University Medical Center

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C.R. Leemans

VU University Medical Center

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F.J. Lagerwaard

Erasmus University Rotterdam

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A. Bruynzeel

VU University Medical Center

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O. Bohoudi

VU University Medical Center

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M. Palacios

VU University Medical Center

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