Jasper J. Quak
VU University Amsterdam
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Featured researches published by Jasper J. Quak.
Cancer | 1999
A E R D Marian van Bokhorst-de van der Schueren; Paul A. M. van Leeuwen; Dirk J. Kuik; W. Martin C. Klop; Hans P. Sauerwein M.D.; Gordon B. Snow; Jasper J. Quak
Malnutrition has been recognized as a poor prognostic indicator for cancer treatment–related morbidity and mortality in general, and it is reported to affect 30–50% of all patients with head and neck cancer. In this study, the correlation of nutritional status with 3‐year survival was studied prospectively in 64 patients with T2–T4 carcinomas of the head and neck who were treated surgically with curative intent; the surgery was often followed by radiotherapy.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1997
Marian A.E. van Bokhorst-de van der Schueren; Paul A. M. van Leeuwen; Hans P. Sauerwein; Dirk J. Kuik; Gordon B. Snow; Jasper J. Quak
Malnutrition is reported frequently in head and neck cancer patients. The impact of malnutrition on surgical outcome is not clearly understood. The purpose of this study was to define the usefulness of six different parameters in scoring malnutrition and to determine the nutritional parameter primarily related to postoperative complications.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2003
Pepijn A. Borggreven; Dirk J. Kuik; Jasper J. Quak; Remco de Bree; Gordon B. Snow; C. René Leemans
Identification of factors, especially comorbidity, that affect the incidence and severity of complications in head and neck cancer patients.
Clinical Nutrition | 1998
M.A.E. van Bokhorst-de van der Schueren; B. M. E. Von Blomberg-Van Der Flier; R.K. Riezebos; Petra E. T. Scholten; Jasper J. Quak; Gordon B. Snow; P.A.M. van Leeuwen
Malnutrition is reported to occur in approximately 30% of head and neck cancer patients. Also, impaired immunocompetence is described as a common phenomenon in this patient group. The purpose of this study was to assess the possible relationship between malnutrition and some prognostically important immune parameters in head and neck cancer patients. Thirty-two malnourished (recent weight loss >/= 10%) and 34 well-nourished patients undergoing curative treatment for advanced head and neck cancer were studied prospectively, and six parameters of their immune status (leucocytes, lymphocytes, lymphocyte phenotyping, monocytes, HLA-DR expression on monocytes and serum interleukin-10) were determined on the day of panendoscopy. Reference values for monocytes, HLA-DR expression and interleukin-10 were obtained from 43 healthy controls. Although the number of monocytes was elevated in both patient groups, the HLA-DR expression on these monocytes was significantly lower in the malnourished than in the well-nourished and control groups. Tumor stage, tumor localization, recurrence after initial radiotherapy, age and gender were not correlated to HLA-DR expression. No relationships emerged between nutritional status and lymphocyte subsets. Malnourished head and neck cancer patients show a significantly lower HLA-DR expression on monocytes than well-nourished ones and healthy controls. According to the literature this would imply an increased risk for postoperative complications. Indeed, postoperative complications occur more frequently in malnourished than in well-nourished patients.
Laryngoscope | 2004
Remco de Bree; Chris Hartley; L.E. Smeele; Dirk J. Kuik; Jasper J. Quak; C. René Leemans
Objective: To assess the results of the use of the free radial forearm flap in terms of objective morbidity and subjective patient response.
Otolaryngology-Head and Neck Surgery | 2001
Remco de Bree; Dinesh Mehta; Gordon B. Snow; Jasper J. Quak
BACKGROUND: Intracranial metastases are rarely clinically diagnosed in patients with head and neck squamous cell carcinoma. Only 7 patients with metastases to the cavernous sinus from head and neck squamous cell carcinomas have been reported. METHODS: A retrospective study revealed 13 patients with intracranial metastases of head and neck squamous cell carcinoma. In a 53-year-old woman a cavernous sinus metastasis of a laryngeal carcinoma was histologically diagnosed by using a CT-guided surgical navigation system and was treated with stereotactic radiotherapy. RESULTS: The mean survival was 4.3 months. Predictive factors for longer survival were absence of extracranial disease, age younger than 60 years, and treatment with radiotherapy. CONCLUSIONS: The prognosis for patients with intracranial disease is poor. The current development of computer-assisted stereotactic navigation and stereotactic radiotherapy may facilitate surgical diagnostic exploration and improve treatment, especially in patients without extracranial disease.
Clinical Otolaryngology | 2007
R. de Bree; R. Reith; Jasper J. Quak; Ca Uyl-de Groot; M van Agthoven; Charles R. Leemans
Objectives: The free radial forearm flap has replaced the pedicled pectoralis major myocutaneous flap and it has become the ‘workhorse flap’ used by many head and neck reconstructive surgeons for soft tissue reconstructions. Cost implications of radial forearm flap reconstruction within the context of the overall health care in a particular system need to be investigated particularly before it is labelled as ‘costly only’.
Experimental Cell Research | 1991
Ad H. G. J. Schrijvers; Martijn Gerretsen; Jan M. Fritz; Marijke van Walsum; Jasper J. Quak; Gordon B. Snow; Guus A.M.S. van Dongen
Monoclonal antibody (MAb) E48 recognizes a 20- to 22-kDa antigen expressed by human squamous and transitional epithelia and their neoplastic counterparts. Histochemical examination of these tissues revealed distinct surface labeling with MAb E48. To investigate the subcellular localization of the E48 antigen we have performed electron microscopical analysis. In cells of normal oral mucosa, the E48 antigen was expressed on the plasmalemma, particularly associated with desmosomes, suggesting involvement of the E48 antigen in intercellular adhesion. Furthermore, the level of expression of the E48 antigen appeared to be influenced by the cellular organization. In squamous cell carcinoma (SCC) cell lines grown in vitro as subconfluent monolayer cultures, the E48 antigen expression was low. However, E48 antigen expression increased when SCC cells were grown to confluency. E48 antigen expression was similarly high when SCC cell lines were cultured under conditions promoting three-dimensional growth either as colonies within floating collagen gels or as xenograft in tumor-bearing nude mice. Further evidence for the involvement of the E48 antigen in cell-cell adhesion was found when SCC cells were grown within collagen gels in the presence of MAb E48: no spherical colonies were formed, but cells grew out to colonies composed of single cells. Moreover, in this culture system the percentage of SCC cells growing out to colonies was decreased by the presence of MAb E48. These findings indicate that the E48 antigen is involved in the structural organization of squamous tissue and might have a role in intercellular adhesion.
European Journal of Nuclear Medicine and Molecular Imaging | 1998
Remco de Bree; Dirk J. Kuik; Jasper J. Quak; Jan C. Roos; Michiel W. M. van den Brekel; J. A. Castelijns; Frank W. van Wagtendonk; Henri Greuter; Gordon B. Snow; Guus A.M.S. van Dongen
Abstract. Radioimmunotherapy (RIT) seems to be a realistic option for eradication of minimal residual squamous cell carcinoma of the head and neck (HNSCC), although uptake levels of radiolabelled monoclonal antibodies (MAbs) in tumour tissue vary strongly. The aim of this study was to obtain greater insight into the factors influencing the accumulation of MAbs in HNSCC. Twenty-seven HNSCC patients were injected with radiolabelled MAb E48 or U36 and underwent surgery 2 days after injection. Radioactivity was measured in tumour biopsies taken from the surgical specimen. Uptake levels were correlated with various patient, tumour and MAb characteristics, including age, sex, site, TNM stage, volume as assesssed by computed tomography or magnetic resonance imaging, degree of differentiation, antigen expression of the tumour, the particular MAb that had been injected and the MAb dose. A stepwise regression multivariate analysis showed that tumour volume is the most significant prognostic factor (P=0.01) for MAb uptake. In conclusion, a significantly higher MAb uptake is found in small tumours as compared to larger tumours. Therefore, RIT may be particularly effective in head and neck cancer patients when used in an adjuvant setting.
Journal of Parenteral and Enteral Nutrition | 2000
Marian A.E. van Bokhorst-de van der Schueren; B. Mary E. von Blomberg-van der Flier; Dirk J. Kuik; Petra E. T. Scholten; Michiel P. C. Siroen; Gordon B. Snow; Jasper J. Quak; Paul A. M. van Leeuwen
BACKGROUND Patients with advanced stages of head and neck cancer are often characterized by malnutrition and by an impaired immune system. Because some of the suppressed immune parameters were shown to be of prognostic importance in trauma and sepsis, we investigated whether these would also correlate with survival in head and neck cancer. METHODS Severely malnourished head and neck cancer patients undergoing ablative and reconstructive surgery were followed prospectively and their perioperative immune parameters were related to long-term survival. RESULTS Forty-nine patients with a preoperative weight loss of more than 10% were followed up for a period of at least 16 months after surgery. Analyses of variance revealed that preoperative human leukocyte antigen-DR (HLA-DR) expression on monocytes and endotoxin-induced production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were different between patients who survived and patients who died. Proportional hazards identified a weight loss of more than 12%, the presence of coexistent disease, and an HLA-DR expression on monocytes below the cutoff points (mean fluorescence index < 15, peak channel index < 9) to be of significant influence on survival. CONCLUSIONS In addition to known prognostic parameters such as tumor stage, coexistent disease, and weight loss, the immune parameters HLA-DR expression on monocytes and endotoxin-induced cytokine production may carry prognostic value in cancer patients. Immunomodulating therapies leading to improvement of these parameters might in the future lead to increased options for treatment.