Iris M. C. van der Ploeg
Netherlands Cancer Institute
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Iris M. C. van der Ploeg.
Journal of Clinical Oncology | 2011
Augustinus P.T. van der Ploeg; Alexander C.J. van Akkooi; Piotr Rutkowski; Zbigniew I. Nowecki; Wanda Michej; Angana Mitra; Julia Newton-Bishop; Martin G. Cook; Iris M. C. van der Ploeg; Omgo E. Nieweg; Mari F.C.M. van den Hout; Paul A. M. van Leeuwen; Christiane Voit; Francesco Cataldo; Alessandro Testori; Caroline Robert; Harald J. Hoekstra; Cornelis Verhoef; Alain Spatz; Alexander M.M. Eggermont
PURPOSE Prognosis in patients with sentinel node (SN)-positive melanoma correlates with several characteristics of the metastases in the SN such as size and site. These factors reflect biologic behavior and may separate out patients who may or may not need additional locoregional and/or systemic therapy. PATIENTS AND METHODS Between 1993 and 2008, 1,080 patients (509 women and 571 men) were diagnosed with tumor burden in the SN in nine European Organisation for Research and Treatment of Cancer (EORTC) melanoma group centers. In total, 1,009 patients (93%) underwent completion lymph node dissection (CLND). Median Breslow thickness was 3.00 mm. The median follow-up time was 37 months. Tumor load and tumor site were reclassified in all nodes by the Rotterdam criteria for size and in 88% by the Dewar criteria for topography. RESULTS Patients with submicrometastases (< 0.1 mm in diameter) were shown to have an estimated 5-year overall survival rate of 91% and a low nonsentinel node (NSN) positivity rate of 9%. This is comparable to the rate in SN-negative patients. The strongest predictive parameter for NSN positivity and prognostic parameter for survival was the Rotterdam-Dewar Combined (RDC) criteria. Patients with submicrometastases that were present in the subcapsular area only, had an NSN positivity rate of 2% and an estimated 5- and 10-year melanoma-specific survival (MSS) of 95%. CONCLUSION Patients with metastases < 0.1 mm, especially when present in the subcapsular area only, may be overtreated by a routine CLND and have an MSS that is indistinguishable from that of SN-negative patients. Thus the RDC criteria provide a rational basis for decision making in the absence of conclusions provided by randomized controlled trials.
The Journal of Nuclear Medicine | 2007
Iris M. C. van der Ploeg; Renato A. Valdés Olmos; Omgo E. Nieweg; Emiel J. Th. Rutgers; Bin B. R. Kroon; Cornelis A. Hoefnagel
The recently introduced SPECT/CT integrates the physiologic data of SPECT with the anatomic data of CT into a single image. The purpose of this pilot study was to explore the additional value of SPECT/CT in breast cancer patients and melanoma patients with inconclusive planar image findings. Methods: Thirty-one patients had planar lymphoscintigrams showing unexpected lymphatic drainage, 6 had lymphoscintigrams that were difficult to interpret, and 3 showed no drainage on planar imaging. SPECT/CT was performed immediately after delayed planar imaging. Results: In 4 patients, SPECT/CT showed 6 additional sentinel nodes, of which 2 were tumor-positive and led to upstaging and tailored management in 5% of patients. SPECT/CT depicted sentinel nodes in 3 patients whose delayed planar imaging had shown no drainage. Conclusion: SPECT/CT was of additional value in finding the exact anatomic location of sentinel nodes in patients with inconclusive planar image findings. SPECT/CT also detected sentinel nodes in addition to those found on planar images, and SPECT/CT detected sentinel nodes in patients whose planar images had shown none.
Journal of Surgical Oncology | 2009
Lenka Vermeeren; Iris M. C. van der Ploeg; Renato A. Valdés Olmos; Willem Meinhardt; W. Martin C. Klop; Bin B. R. Kroon; Omgo E. Nieweg
The value of SPECT/CT for detection and localization of sentinel nodes is reviewed. SPECT/CT depicts extra sentinel nodes and identifies non‐nodal tracer accumulation. SPECT/CT is indicated in patients with complex lymphatic drainage as often present in patients with head, neck and scapular melanoma, breast cancer patients with extra‐axillary sentinel nodes and patients with tumors draining to pelvic nodes. SPECT/CT also clarifies the drainage pattern of inconclusive conventional images (non‐visualization or unclear location of the nodes). J. Surg. Oncol. 2010;101:184–190.
The Journal of Nuclear Medicine | 2009
Joost A.P. Leijte; Iris M. C. van der Ploeg; Renato A. Valdés Olmos; Omgo E. Nieweg; Simon Horenblas
The reliability of sentinel node biopsy is dependent on the accurate visualization and identification of the sentinel node(s). It has been suggested that extensive metastatic involvement of a sentinel node can lead to blocked inflow and rerouting of lymph fluid to a “neo–sentinel node” that may not yet contain tumor cells, causing a false-negative result. However, there is little evidence to support this hypothesis. Recently introduced hybrid SPECT/CT scanners provide both tomographic lymphoscintigraphy and anatomic detail. Such a scanner enabled the present study of the concept of tumor blockage and rerouting of lymphatic drainage in patients with palpable groin metastases. Methods: Seventeen patients with unilateral palpable and cytologically proven metastases in the groin underwent bilateral conventional lymphoscintigraphy and SPECT/CT before sentinel node biopsy of the contralateral groin. The pattern of lymphatic drainage in the 17 palpable groin metastases was evaluated for signs of tumor blockage or rerouting. Results: On the CT images, the palpable node metastases could be identified in all 17 groins. Four of the 17 palpable node metastases (24%) showed uptake of radioactivity on the SPECT/CT images. In 10 groins, rerouting of lymphatic drainage to a neo–sentinel node was seen; one neo–sentinel node was located in the contralateral groin. A complete absence of lymphatic drainage was seen in the remaining 3 groins. Conclusion: The concept of tumor blockage and rerouting was visualized in 76% of the groins with palpable metastases. Precise physical examination and preoperative ultrasound with fine-needle aspiration cytology may identify nodes with considerable tumor invasion at an earlier stage and thereby reduce the incidence of false-negative results.
Annals of Surgical Oncology | 2009
Iris M. C. van der Ploeg; Renato A. Valdés Olmos; Bin B. R. Kroon; M.W.J.M. Wouters; Michiel W. M. van den Brekel; Wouter V. Vogel; Cornelis A. Hoefnagel; Omgo E. Nieweg
BackgroundThe hybrid single-photon emission computed tomography camera with integrated CT (SPECT/CT) fuses tomographic lymphoscintigrams with anatomical CT data. SPECT/CT shows the exact anatomical location of a sentinel node and may detect additional drainage. The purpose of this study was to explore its potential in patients with melanoma.MethodsWe studied 85 patients with melanoma with conventional lymphoscintigrams that were difficult to interpret (51 patients), that showed an unusual drainage pattern (33 patients), or with nonvisualization (1 patient). Forty-one patients had melanoma on an extremity, 31 on the trunk, and 14 in the head and neck region. SPECT/CT was performed following late conventional imaging without reinjection of the radiopharmaceutical.ResultsConventional imaging suggested 214 sentinel nodes in 84 of the 85 patients (99%). SPECT/CT showed these same nodes and 12 extra sentinel nodes in seven patients (8%). Ten of these additional nodes were harvested, of which three nodes of two patients harbored metastases. There was a clear advantage of SPECT/CT in 30 patients (35%), resulting in a different incision in 17 patients, an incision at another site in 8, and an extra incision in 5 patients. The value was questionable in 19 patients (22%) in whom sentinel nodes were more clearly visualized by SPECT/CT, although the incision remained unchanged. There was no additional value of SPECT/CT in 36 patients (42%).ConclusionsSPECT/CT detects additional drainage and shows the exact anatomical location of sentinel nodes in patients with inconclusive conventional lymphoscintigrams. SPECT/CT facilitates surgical exploration in difficult cases and may improve staging.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2011
Lenka Vermeeren; Renato A. Valdés Olmos; W. Martin C. Klop; Iris M. C. van der Ploeg; Omgo E. Nieweg; Alfons J. M. Balm; Michiel W. M. van den Brekel
The additional value of single photon emission computed tomography with CT (SPECT/CT) for detection and localization of sentinel nodes in patients with a melanoma of the head and neck was determined.
European Journal of Nuclear Medicine and Molecular Imaging | 2009
Iris M. C. van der Ploeg; Omgo E. Nieweg; Bin B. R. Kroon; Emiel J. Th. Rutgers; Marie-Jeanne T. F. D. Baas-Vrancken Peeters; Wouter V. Vogel; Cornelis A. Hoefnagel; Renato A. Valdés Olmos
PurposeThe recently introduced hybrid single-photon emission computed tomography camera with integrated CT (SPECT/CT) fuses tomographic lymphoscintigrams with anatomical data from CT. The purpose of this study was to explore this sophisticated technique in lymphatic mapping in breast cancer patients.MethodsWe studied 134 patients who underwent SPECT/CT immediately after late planar imaging when these images showed an unusual drainage pattern (85 patients), a pattern that was difficult to interpret (27 patients), or nonvisualization (22 patients).ResultsPlanar imaging suggested 271 sentinel nodes in 112 of the 134 patients (84%). SPECT/CT showed 269 of these same nodes and indicated that two sites of radioactivity were caused by skin contamination. SPECT/CT visualized 19 additional sentinel nodes in 15 patients, of whom 11 had non-visualization on planar images. One or more tumour-positive sentinel nodes were seen in 27 patients, and in 4 of these patients (15%), these were visualized only by SPECT/CT. SPECT/CT had no additional value for the surgical approach in 11 patients with persisting nonvisualization (8%), and was of questionable value in 67 other patients (50%). Based on the SPECT/CT images, a more precise incision was made in 48 patients (36%), an extra incision was made in 6 (4%), and an incision was omitted in 2 (1.5%).ConclusionSPECT/CT detected additional sentinel nodes and showed the exact anatomical location of sentinel nodes in breast cancer patients with inconclusive planar images. SPECT/CT was able to visualize drainage in patients whose planar images did not reveal a sentinel node. Therefore, SPECT/CT facilitates surgical exploration in difficult cases and may improve staging.
World Journal of Surgery | 2008
Iris M. C. van der Ploeg; Renato A. Valdés Olmos; Bin B. R. Kroon; Omgo E. Nieweg
BackgroundConventional lymphoscintigraphy does not always define the exact anatomic location of a sentinel node. The lymphatic drainage pattern may be unusual or may not be shown at all. The recently introduced hybrid SPECT/CT imaging could help overcome these difficulties. SPECT is a tomographic version of conventional lymphoscintigraphy and the images have better contrast and resolution. When fused with the anatomical details provided by CT into one image, a meaningful surgical “roadmap” can be created. So far, there is little literature on the use of hybrid SPECT/CT in lymphatic mapping in patients with breast cancer. The purpose of this review was to report on these publications, including our own experience, focusing on patient selection, SPECT/CT settings, anatomic localization, and the detection of additional sentinel nodes.MethodsThe majority of investigators did not formulate indications for additional SPECT/CT after conventional imaging but scanned all patients eligible for sentinel node biopsy. The SPECT/CT settings used in the studies of this review were mostly similar, but the methods used for conventional imaging were more variable.ResultsAll studies demonstrated an improved anatomical localization by performing additional SPECT/CT; sentinel nodes outside the axilla or nodes close to the injection site were especially easier to identify. Sentinel nodes were visualized in 89–100% by combined conventional imaging and SPECT/CT, with sentinel nodes depicted only by SPECT/CT in up to 14%.ConclusionIt is concluded that SPECT/CT shows the exact anatomical location of sentinel nodes, detects sentinel nodes not depicted by conventional imaging, and therefore facilitates surgical exploration. The hybrid SPECT/CT has the potential to make image fusion a routine clinical tool that improves lymphatic mapping in patients with breast cancer.
Annals of Surgery | 2009
Iris M. C. van der Ploeg; Bin B. R. Kroon; Ninja Antonini; Renato A. Valdés Olmos; Omgo E. Nieweg
Objective:The purposes of this study were to determine which classification best predicts additional lymph node disease and survival, and to suggest a threshold below which a completion dissection may be omitted. Summary Background Data:Three micromorphometric parameters of melanoma sentinel node metastases were compared: invasion depth from the capsule (Starz-classification), maximum diameter (Rotterdam-criteria), and location within the node (Dewar-classification). Methods:The pathology slides of 116 patients with tumor-positive sentinel nodes were reviewed. The follow-up data were obtained from the prospectively kept database. The median follow-up duration was 53 months. Results:Metastases with an invasion depth under 0.3 mm or diameter less than 0.1 mm were not associated with additional involved nodes. Four percent of the patients with metastases with an invasion depth of 0.3 to 1.0 mm had other involved nodes and 3% of the patients with metastases with a diameter of 0.1 to 1.0 mm. Other nodes were involved in 3% of subcapsular metastases, 9% of both subcapsular and parenchymal metastases, and 33% in case of multifocal or extensive disease. The smallest tumor invasion depth and diameter associated with additional involved nodes was 0.4 mm. Only 5-year overall survival in the 3 successive invasion depth categories were statistically significant: 92%, 83%, and 68%. Five-year overall survival was 81% in patients with one involved sentinel node and 60% if there were more. Conclusions:Invasion depth and diameter of the metastasis correlate best with the presence of additional nodal disease. Invasion depth best predicts overall survival. It seems justified to refrain from completion dissection in patients with a sentinel node tumor invasion depth up to 0.4 mm.
Annals of Surgery | 2009
Iris M. C. van der Ploeg; Bin B. R. Kroon; Ninja Antonini; Renato A. Valdés Olmos; Omgo E. Nieweg
Objective:The purpose of this study was to evaluate the micromorphometric Starz-classification in melanoma patients. Summary Background Data:The micromorphometric Starz-classification suggests that melanoma patients with a sentinel node metastasis invading no more than 0.3 mm (S-I) or 0.31 to 1.0 mm (S-II) below the capsular level can be spared further surgery, while invasion of the metastasis of more than 1.0 mm (S-III) implies a need for completion dissection. Methods:Seventy patients with sentinel node metastases were studied. Twenty patients with an S-I or S-II classification were spared further surgery and 50 S-III patients underwent completion dissection. The median follow-up time was 33 months. Results:No lymph node recurrences were detected in the 20 S-I, II patients. Six of the 50 S-III patients (12%) had additional involved nodes in the dissection specimen. In these patients no recurrences developed in the cleared regional basins. Overall 3-year survival was 100% in the S-I, II patients and 80% in the S-III patients (P = 0.04). Three-year disease-free survival rates were 83% and 60%, respectively (P = 0.40). Conclusions:This study suggests that further surgery is unnecessary in S-I and S-II patients, while it does seem prudent to carry out completion dissection in S-III patients. The distinct survival difference between the 2 groups of patients suggests that the S-classification also has prognostic implications.
Collaboration
Dive into the Iris M. C. van der Ploeg's collaboration.
Marie-Jeanne T. F. D. Baas-Vrancken Peeters
Netherlands Cancer Institute
View shared research outputs