Axillary Lymph Node Metastases in Patients with Breast Carcinomas: Assessment with Nonenhanced versus USPIO-enhanced MR Imaging

Purpose: To investigate the diagnostic performance and clinical feasibility of diffusion-weighted magnetic resonance imaging (MRI) using ultrasmall superparamagnetic iron oxide (USPIO) in the evaluation of axillary lymph nodes (ALNs) in patients with breast cancer. Materials and Methods:Sixteen patients with known breast cancer underwent 1.5 T MRI. Axial diffusionweighted images (DWIs) and conventional T1-and T2*-weighted images (CIs) were acquired before and 24-36 hours after intravenous administration of USPIO. Detection of ALNs was evaluated on DWIs in comparison with CIs. The apparent diffusion coefficient values (ADCvs) of the nonmetastatic and metastatic nodes in precontrast DWIs were determined. The diagnostic performance of DWI using USPIO was compared with that of CIs using USPIO with pathological correlation.Results: Out of a total of 286 ALNs, 216/286 (76%) nodes were detected on DWIs and 238/286 (83%) on CIs. The differences in the ADCvs between metastatic and nonmetastatic nodes were not significant (P ¼ 0.06). Sensitivity of CIs and DWIs using USPIO were respectively 70% and 83%, specificity 98% and 98%, and overall accuracy 93% and 95%.Conclusion: Although the detection on DWIs of ALNs in patients with breast cancer was inferior compared to CIs, the sensitivity and accuracy of DWIs using USPIO were superior in the diagnosis of ALNs metastasis.

Section: Discussionmentioning

confidence: 99%

“…With regard to axillary lymph node staging, there are published data for USPIO-enhanced MRI (17)(18)(19)(20). Researchers in those studies reported a sensitivity of 73%-100% and a specificity of 92%-98% in the nodeby-node evaluation using USPIO.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of axillary lymph nodes by diffusion‐weighted MRI using ultrasmall superparamagnetic iron oxide in patients with breast cancer: Initial clinical experience

Nakai

Matsuki

Harada

et al. 2011

“…The application of ultra-small iron oxide particles as contrast agents for lymph node identification with MR is presently evolving (17). It is likely that further developments in MR imaging technology, and nanotechnology will lead to the expansion of the application of MR to loco-regional staging and treatment of breast cancer (18,19).…”

Section: Discussionmentioning

confidence: 99%

Magnetic resonance imaging for axillary staging in patients with breast cancer

Mortellaro

Marshall

Singer

et al. 2009

107

103

Purpose:To determine the utility of MRI for assessing axillary lymph node status in patients with breast cancer. Materials and Methods:A consecutive series of patients who underwent breast MR before surgical management of breast cancer with axillary sampling between 2005 and 2007 were identified. MRs were evaluated for the number of nodes, contrast kinetics, nodal area, and number of nodes with no fatty hilum. Data were analyzed in the context of final breast pathology, sentinel lymph node status, and axillary nodal status. Correlations were analyzed using Kendall's -b test. Reported P values are one-sided.Results: Fifty-six females (median ϭ 58 years) were studied. Sentinel lymph nodes (SLN) were positive in 15/56 patients (27%). All SLN ϩ patients (n ϭ 15) had completion axillary dissection. Extent of nodal disease was 1 (n ϭ 3), 2 (n ϭ 4), Ͼ2 (n ϭ 8). Presence of any axillary lymph node with no fatty hilum and the number of nodes with no fatty hilum on MR significantly correlated with pathologic node positivity (P ϭ 0.04); while kinetics, node number, and node size did not correlate. Conclusion:Breast MR may be useful in the assessment of axillary nodes in patients with breast cancer.

“…These differences in signal intensity between normal and metastatic nodes can be easily detected visually (3). Several clinical studies have demonstrated that USPIO-enhanced MR is a particularly promising technique that improves the sensitivity and specificity of metastatic lymph node detection in pelvic, head and neck, chest, and other malignancies (2,(4)(5)(6)(7)(8)(9)(10)(11)(12)(13).…”

mentioning

confidence: 99%

Possible pathological basis for false diagnoses of lymph nodes by USPIO‐enhanced MRI in rabbits

Lei

Xue

et al. 2010

Purpose: To determine the cause of misdiagnosis of lymph nodes in ultrasmall superparamagnetic iron oxide (USPIO) enhanced magnetic resonance imaging (MRI) using histological findings in rabbit tumor and inflammatory models.Materials and Methods: Thirty-six rabbits were randomly divided into inflammatory and tumor groups. MRI of the popliteal fossa was performed before and 24 hours after USPIO administration. Diagnoses of popliteal lymph nodes were evaluated based on dedicated criteria and were compared with histological and electronic microscopic findings.Results: There were 46 inflammatory and 26 metastatic lymph nodes. Sensitivity, specificity, and positive and negative predictive values of the diagnosis of nodal metastasis were 84.6%, 87.0%, 78.6%, and 90.9%, respectively. There were four false-negatives with subcapsular metastatic foci and six false-positives with predominant cortex and paracortex hyperplasia. Electron microscopy showed that in inflammatory nodes, cytophagic bubbles contain many USPIO particles, while in metastatic nodes they contained predominantly cellular residues.Conclusion: Diagnosis of lymph node malignancy is largely determined by the location and number of metastatic tumor cells. A profound understanding of the physiological role of macrophages in nodes with tumor burden will contribute to better diagnoses for clinical application. THE ACCURATE DETECTION of metastasis in lymph nodes is crucial for the prognosis and treatment plans of patients with malignant tumor. In the last few years ultrasmall superparamagnetic iron oxide (USPIO) agents have revolutionized lymph node imaging and have introduced functional imaging to conventional magnetic resonance imaging (MRI) (1-3). The nanoparticles are internalized by macrophages within the lymph nodes, and these intracellular iron-containing particles cause changes in magnetic properties detectable by MRI. These differences in signal intensity between normal and metastatic nodes can be easily detected visually (3). Several clinical studies have demonstrated that USPIO-enhanced MR is a particularly promising technique that improves the sensitivity and specificity of metastatic lymph node detection in pelvic, head and neck, chest, and other malignancies (2,4-13).Despite lots of promising results concerning USPIOenhanced MRI, there are still many important challenges to overcome, in which one problem is false-positive and false-negative results, affecting the accuracy of diagnosis (2,4-12). Harisinghani et al (2) reported that there were metastasis nodes that went undetected, and the false diagnosis was not negligible.In this work we established an animal model of inflammation and tumor in rabbit to thoroughly analyze the USPIO enhancement pattern of nodes. We used all types of images strictly paralleling the histologic microstructure of nodes in order to identify possible reasons for false diagnoses to refine the imaging diagnostic criteria of malignancy in lymph nodes. MATERIALS AND METHODS Animal ModelsThe experiments were performed using 36...