J. van der Sijp
VU University Amsterdam
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Publication
Featured researches published by J. van der Sijp.
British Journal of Surgery | 2005
Maarten C. Jansen; F. H. van Duijnhoven; R. van Hillegersberg; Arjen M. Rijken; F. van Coevorden; J. van der Sijp; Warner Prevoo; T.M. van Gulik
Radiofrequency ablation (RFA) is a new treatment for liver tumours. Complications encountered after RFA in the Netherlands were evaluated in the present study.
Scandinavian Journal of Gastroenterology | 2004
T. J. Blokhuis; M. C. van der Schaaf; M.P. van den Tol; E.F.I. Comans; Radu A. Manoliu; J. van der Sijp
Background: In the literature, promising results have been obtained with radiofrequency ablation (RFA) of primary liver malignancies (e.g. hepatocellular carcinoma, HCC) and secondary liver malignancies (e.g. metastases of colorectal tumors). In our center, positron emission tomography with FDG (FDG-PET) and computed tomography (CT) were used for follow-up. Patient outcome was compared with that in the literature, and PET and CT were analyzed regarding positive and negative predictive values for early detection of tumor recurrence. Methods: The data were analyzed of patients who were treated with RFA for primary or secondary liver tumors between January 1999 and December 2002. Indications for treatment with RFA were liver tumors that could not be resected owing to size, number, or tumor location. In all patients, a CT scan was performed before RFA, and follow-up was performed with a CT scan in all patients and with an additional PET scan at various intervals in 11 patients. At evaluation with PET, tumor recurrence was defined as positive uptake of tracer either at the previous RFA lesion or at a new site in the liver. Results: In total, 15 patients (8 M, 7 F) were treated in 21 sessions with RFA. The mean follow-up period was 16.8 months (range: 7-42). Average age of the patients was 63 years (range: 40-74). One patient had a primary liver tumor; all other patients had metastases of the breast (1), ovary (1), renal cells (1), and colorectal carcinoma (11 patients). The mean number of tumors per patient was 2.7 (range: 1-5). No treatment-related morbidity or mortality occurred. In 4 of 11 patients evaluated with PET at a mean period of 6.8 months, positive uptake of tracer was noted. At CT evaluation, tumor recurrence was observed in 4 of these patients, at a mean time of 9.8 months. Two patients (13.3%) died of cancer recurrence during follow-up. Conclusions: Tumor recurrence is comparable with that in other studies. Centrally located tumors showed more recurrence than peripheral tumors. The use of PET in combination with CT scan at follow-up may lead to earlier detection of tumor recurrence than contrast-enhanced CT alone.
Journal of Clinical Pathology | 2004
Hester A. Gietema; Ronald J.C.L.M. Vuylsteke; I A de Jonge; P.A.M. van Leeuwen; Barbara G. Molenkamp; J. van der Sijp; S. Meijer; P. J. van Diest
Aims: To evaluate in detail the extent to which step sectioning and immunohistochemical examination of sentinel lymph nodes (SLNs) in patients with melanoma reveal additional node positive patients, to arrive at a sensitive yet workable protocol for histopathological SLN examination. Methods: The study comprised 29 patients with one or more positive SLN after a successful SLN procedure for clinical stage I/II melanoma. SLNs were lamellated into pieces of approximately 0.5 cm in size. One initial haematoxylin and eosin (H&E) stained central cross section was made for each block. When negative, four step ribbons were cut at intervals of 250 μm. One section from each ribbon was stained with H&E, and one was used for immunohistochemistry (IHC). Results: When taking the cumulative total of detected metastases at level 5 as 100%, the percentage of SLN positive patients increased from 79%, 83%, 83%, 90% to 93% in the H&E sections through levels 1–5, and with IHC these values were 83%, 86%, 90%, 97%, and 100%, respectively. One of six patients in whom metastases were detected at levels 2–5 only had metastases in the subsequent additional lymph node dissection. Conclusions: Multiple level sectioning of SLNs (five levels at 250 μm intervals) and the use of IHC detects additional metastases up to the last level in melanoma SLNs. Although more levels of sectioning might increase the yield even further, this protocol ensures a reasonable workload for the pathologist with an acceptable sensitivity when compared with the published literature.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2003
A.J.W. van der Meij; J.A. Baart; B. Prahl-Andersen; P.J. Kostense; J. van der Sijp; D.B. Tuinzing
OBJECTIVE The purpose of this study was to determine the relationship between cleft width and the residual amount of bone after bone grafting in 53 unilateral cleft lip and palate patients. STUDY DESIGN The fate of the bone graft was determined by the residual amount of bone calculated from computed tomography scans taken immediately after surgery and 1 year postoperatively. Initial cleft width was measured on the computed tomography scans taken immediately after bone grafting. RESULTS An average cleft width of 6.4 mm (range 3.0-12.2 mm) was found. The average amount of residual bone in the cleft area after 1 year was 64% of the initial bone graft. Linear regression analysis showed that a significant correlation (r = -0.29, P =.04) was found for cleft width in relation to the percentage of residual bone after 1 year. CONCLUSION The regression analysis indicates that a relation between cleft width and the fate of the bone graft exists. Bone grafts in wider clefts are more prone to resorption than those in more narrow ones.
Scandinavian Journal of Gastroenterology | 2006
S. E. J. Terwisscha Van Scheltinga; F. C. Den Boer; Rik Pijpers; G. A. Meyer; A. F. Engel; R. Silvis; Sybren Meijer; J. van der Sijp
Background. Nodal staging accuracy is important in the prognosis and selection of patients for chemotherapy. This prospective study aims to assess the feasibility and accuracy of the sentinel lymph node procedure (SNP) using radiocolloid and blue dye in colon carcinoma. Methods. In 56 patients, lymphatic mapping was accomplished by means of intraoperatively injecting patent blue and nanocoll subserosally around the tumour. Sentinel nodes (SNs) were harvested ex-vivo. Nodes were stained with H&E. If lymph nodes were interpreted as negative for metastatic tumour, serial sectioning and immunohistochemical staining were performed. Results. At least one SN was detected in 49 of 53 patients (92.5%). Three patients were excluded because of preoperatively detected metastases. Overall, 121 SN were harvested with a mean of 2.2 SN/patients. Eighteen patients had tumour positive nodes. In four patients, pathological nodes were palpable during operation and were excluded. The SN was histologically negative in 2 of 14 patients with positive nodes (false-negative rate 14.3%). In 5 of 14 patients with positive nodes, the SN was the exclusive site of regional nodal metastasis. Four patients were upstaged by immunohistochemical staining (28.6%). The negative predictive value was 93.9% and the overall accuracy 95.6%. Scintigraphy was done in 17 patients. In three patients the SN was detected only by this modality. Discussion. The SN biopsy with the combined technique proved a feasible technique with a steep learning curve. It can change the initial staging from stage II to stage III colon carcinoma. Scintigraphy can improve the success rate of the technique.
British Journal of Surgery | 2018
E.M. de Leede; N.J. van Leersum; Kroon Hm; V. van Weel; J. van der Sijp; Bert A. Bonsing
Postoperative ileus is a common complication of abdominal surgery, leading to patient discomfort, morbidity and prolonged postoperative length of hospital stay (LOS). Previous studies suggested that chewing gum stimulates bowel function after abdominal surgery, but were underpowered to evaluate its effect on LOS and did not include enhanced recovery after surgery (ERAS)‐based perioperative care. This study evaluated whether chewing gum after elective abdominal surgery reduces LOS and time to bowel recovery in the setting of ERAS‐based perioperative care.
British Journal of Surgery | 2011
Bastiaan Wiering; Wim J.G. Oyen; E.M.M. Adang; J. van der Sijp; R. Roumen; K. P. de Jong; Theo J.M. Ruers; Paul F. M. Krabbe
Journal of Clinical Oncology | 2011
Emile E. Voest; Nikol Snoeren; Sander B. Schouten; Andries M. Bergman; E. van Werkhoven; Olaf Loosveld; T.M. van Gulik; J. M. Smit; Annemieke Cats; E. Boven; E.J. Hesselink; Arjen M. Rijken; M. Tol; O. Dalesio; Henk M.W. Verheul; R.A.E.M. Tollenaar; J. van der Sijp; I. H. M. Borel Rinkes; R. van Hillegersberg
Breast Cancer Research and Treatment | 2005
Hans Fabry; B.M. Zonderhuis; Sybren Meijer; J. Berkhof; P.A.M. van Leeuwen; J. van der Sijp
European Journal of Nuclear Medicine and Molecular Imaging | 2008
Bastiaan Wiering; Paul F. M. Krabbe; J. van der Sijp; R. Roumen; K. P. de Jong; Emile F.I. Comans; Jan Pruim; Helena M. Dekker; T. Ruers; Wim J.G. Oyen