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Featured researches published by O.E. Nieweg.


British Journal of Cancer | 1998

Positron emission tomography for staging of oesophageal and gastroesophageal malignancy.

Ac Kole; J. T. Plukker; O.E. Nieweg; W Vaalburg

Positron emission tomography (PET) with [18F]-fluoro-2-deoxy-D-glucose (FDG) was prospectively investigated as a means of detecting metastatic disease in patients with oesophageal tumours and compared with computerized tomography (CT), with the surgical findings as a gold standard. Twenty-six patients with a malignant tumour of the oesophagus or gastroesophageal junction underwent CT and PET of the chest and the abdomen. Seven patients underwent laparoscopy to establish resectability. Fifteen patients underwent laparotomy without prior laparoscopy. Four patients did not undergo surgery. The primary tumour was visualized in 81% of patients with CT and in 96% with PET. Neither CT nor PET were suited to assess the extent of wall invasion. Surgically assessed nodal status corresponded in 62% with CT and in 90% with PET. Distant metastases were found in five patients with CT and in eight with PET. The diagnostic accuracy of CT in determining resectability was 65% and for PET 88%. For CT and PET together this was 92%. The present study indicates that FDG-PET can be of importance for staging patients with oesophageal tumours. PET has a higher sensitivity for nodal and distant metastases and a higher accuracy for determining respectability than CT. PET and CT together would have decreased ill-advised surgery by 90%.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2000

Sentinel node biopsy for melanoma in the head and neck region

L. Jansen; Heimen Schraffordt Koops; O.E. Nieweg; M. H. E. Doting; Bae Kapteijn; A. J. M. Balm; A. Vermey; John Plukker; Cornelis A. Hoefnagel; D. A. Piers; B. B. R. Kroon

Lymphatic drainage in the head and neck region is known to be particularly complex. This study explores the value of sentinel node biopsy for melanoma in the head and neck region.


Annals of Surgical Oncology | 1997

Detection of local recurrence of soft-tissue sarcoma with positron emission tomography using [18F]fluorodeoxyglucose

Ac Kole; O.E. Nieweg; Rj vanGinkel; Jan Pruim; Hj Hoekstra; Amj Paans; W Vaalburg; H. Schraffordt Koops

AbstractBackground: It is often difficult to detect a local recurrence of soft-tissue sarcomas due to disturbance of the normal anatomy by previous surgery and radiotherapy. The aim of this study was to assess the value of positron emission tomography (PET) with [18F]fluoro-2-deoxy-d-glucose (FDG) for detecting local recurrences. Methods: In the period 1992–1995, 17 patients with proven or suspected local recurrence of soft-tissue sarcoma were examined using FDG-PET. Fifteen of these patients were ultimately proven to have a recurrence. Results: Recurrence was visualized in 14 patients (93%). Small tumors (maximum diameter 0.5 cm) were as easily visible as large lesions (maximum diameter 20 cm). In one patient the PET scan was positive, but the recurrence could not be proven histologically. Recurrence was proven 1 year later. A recurrent low-grade liposarcoma was not visualized. The two patients with benign lesions had a negative PET scan. The mean glucose metabolic rate was calculated to be 13.2 µmol/100 g/min (range 1.9–28.4). A correlation was found between the histological malignancy grade and the metabolic rate (p<0.05; Kruskal-Wallis). Conclusion: PET with FDG is a useful addition to the diagnostic armamentarium for detecting local recurrence of soft-tissue sarcomas and provides an indication of the malignancy grade of the recurrent lesion.


British Journal of Cancer | 2002

Impact of non-axillary sentinel node biopsy on staging and treatment of breast cancer patients

Pieter J. Tanis; O.E. Nieweg; R.A. Valdés Olmos; J.L. Peterse; E.J.Th. Rutgers; Cornelis A. Hoefnagel; B. B. R. Kroon

The purpose of this study was to evaluate the occurrence of lymphatic drainage to non-axillary sentinel nodes and to determine the implications of this phenomenon. A total of 549 breast cancer patients underwent lymphoscintigraphy after intratumoural injection of 99mTc-nanocolloid. The sentinel node was intraoperatively identified with the aid of intratumoural administered patent blue dye and a gamma-ray detection probe. Histopathological examination of sentinel nodes included step-sectioning at six levels and immunohistochemical staining. A sentinel node outside level I or II of the axilla was found in 149 patients (27%): internal mammary sentinel nodes in 86 patients, other non-axillary sentinel nodes in 44 and both internal mammary and other non-axillary sentinel nodes in nineteen patients. The intra-operative identification rate was 80%. Internal mammary metastases were found in seventeen patients and metastases in other non-axillary sentinel nodes in ten patients. Staging improved in 13% of patients with non-axillary sentinel lymph nodes and their treatment strategy was changed in 17%. A small proportion of clinically node negative breast cancer patients can be staged more precisely by biopsy of sentinel nodes outside level I and II of the axilla, resulting in additional decision criteria for postoperative regional or systemic therapy.


British Journal of Surgery | 2004

High incidence of in-transit metastases after sentinel node biopsy in patients with melanoma

Susanne H. Estourgie; O.E. Nieweg; B. B. R. Kroon

The occurrence of in‐transit metastases in patients with a tumour‐positive sentinel node varies greatly between centres and it has been suggested that the incidence is high in this patient group.


Nuclear Medicine Communications | 2001

Improved sentinel node visualization in breast cancer by optimizing the colloid particle concentration and tracer dosage

R.A. Valdés Olmos; Pieter J. Tanis; Cornelis A. Hoefnagel; O.E. Nieweg; S.H. Muller; E.J.Th. Rutgers; M. L. K. Kooi; B. B. R. Kroon

Faint lymph uptake may hamper sentinel node (SN) identification by scintigraphy and subsequent gamma probe localization. The aim of the present study was to evaluate an adjustment in the colloid particle concentration and tracer dosage to optimize mammary lymphoscintigraphy. Scintigraphy was performed in 151 patients with a palpable breast carcinoma and clinically negative axilla: for the first 75 patients (group A) a standard labelling of 0.5 mg nanocolloid with 99Tcm was performed, for the subsequent 76 patients (group B) the labelling dilution volume was reduced from 4 to 2 ml. For both groups the volume of injection was 0.2 ml. Lymph node uptake was evaluated by a 4-step visual score (from 0 = absent to 3+ = very intense), and by count quantification of at 4 h in the first draining SN. The SN visualization rate increased from 93% (70/75) in group A (mean dosage 93.4 MBq, range 57-130 MBq) to 99% (75/76) in group B (mean dosage 106.5 MBq, range 74-139 MBq). The percentage of patients with uptake 3+ was significantly higher (P = 0.001) in group B (51% vs 35% in group A). SN counts were significantly higher for group B (P<0.001). The percentage of patients with less than 2000 counts/node diminished from 45% in group A to 9% in group B (P = 0.001). In group B (P = 0.033) more lymph channels (53% vs 35% in group A) were visualized and for a longer time (26% vs 4% at 4 h). Axillary drainage was seen in 96% in group A and 98% in group B whereas non-axillary drainage was observed in 19% and 25%, respectively. Intraoperative SN identification rate was 97% in group A and 100% in group B. SN metastases were found in 41% of group A and 47% of group B. It is concluded that enhancement of colloid particle concentration and adjustment of tracer dosage led to improved SN identification by substantial increase in lymph node uptake and lymph vessel depiction. A significant reduction of cases with faint SN uptake enables better surgical efficacy.


British Journal of Surgery | 2007

Risk of invasion and axillary lymph node metastasis in ductal carcinoma in situ diagnosed by core-needle biopsy

Philip Meijnen; Hester S. A. Oldenburg; Claudette E. Loo; O.E. Nieweg; Johannes L. Peterse; E.J.T. Rutgers

The aim of the study was to assess the risk of invasion and axillary lymph node metastasis in patients with ductal carcinoma in situ (DCIS) diagnosed by preoperative core‐needle biopsy. The data were used to select criteria for patients in whom sentinel node (SN) biopsy might be indicated.


Annals of Surgical Oncology | 2002

Safety and efficacy of isolated limb perfusion in elderly melanoma patients.

Eva M. Noorda; Bart C. Vrouenraets; O.E. Nieweg; A.N. van Geel; A.M.M. Eggermont; B. B. R. Kroon

BackgroundOlder patients are assumed to have a higher risk of complications from isolated limb perfusion (ILP). A study was performed evaluating the safety and efficacy of ILP in patients older than 75 years with advanced melanoma of the limbs.MethodsA total of 218 therapeutic ILPs with melphalan with or without tumor necrosis factor α were performed in 202 patients with advanced measurable melanoma and were analyzed retrospectively. Fifty-three patients (28%) were 75 years or older.ResultsComplete response rates were 56% for those older than 75 years and 58% for the younger group (P=.79). Locoregional relapse occurred in 56% of the older group versus 51% in the younger group (P=.61). Limb toxicity, systemic toxicity, local complications, and long-term morbidity were similar in both age groups. Perioperative mortality was low, with one procedure-related death in the older group. Older patients stayed in the hospital for a median of 23 days (younger patients, 19 days;P<.01).ConclusionsILP results in similar response rates in the elderly with recurrent melanoma, without increased toxicity, complications, or long-term morbidity compared with younger patients. Older age in itself is not a contraindication for ILP.


British Journal of Surgery | 2007

Excision biopsy of breast lesions changes the pattern of lymphatic drainage

Susanne H. Estourgie; R.A. Valdés Olmos; O.E. Nieweg; Cornelis A. Hoefnagel; E.J.T. Rutgers; B. B. R. Kroon

The aim was to validate the sentinel node biopsy procedure in women who had previous breast excision biopsy by means of determining the reproducibility of lymphoscintigraphy after surgery.


Journal of Oncology | 2009

Sentinel Node Detection in Head and Neck Malignancies: Innovations in Radioguided Surgery

Lenka Vermeeren; W.M.C. Klop; M.W.M. van den Brekel; A. J. M. Balm; O.E. Nieweg; R.A. Valdés Olmos

Sentinel node mapping is becoming a routine procedure for staging of various malignancies, because it can determine lymph node status more precisely. Due to anatomical problems, localizing sentinel nodes in the head and neck region on the basis of conventional images can be difficult. New diagnostic tools can provide better visualization of sentinel nodes. In an attempt to keep up with possible scientific progress, this article reviews new and innovative tools for sentinel node localization in this specific area. The overview comprises a short introduction of the sentinel node procedure as well as indications in the head and neck region. Then the results of SPECT/CT for sentinel node detection are described. Finally, a portable gamma camera to enable intraoperative real-time imaging with improved sentinel node detection is described.

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B. B. R. Kroon

Netherlands Cancer Institute

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R.A. Valdés Olmos

Netherlands Cancer Institute

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A.M.M. Eggermont

Erasmus University Medical Center

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Bart C. Vrouenraets

Netherlands Cancer Institute

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E.J.Th. Rutgers

Netherlands Cancer Institute

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Liesbeth Jansen

University Medical Center Groningen

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W Vaalburg

University of Groningen

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Hj Hoekstra

University of Groningen

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