Superior mediastinal and neck lymphatic mapping in mid- and lower-thoracic esophageal cancer as defined by ferumoxides-enhanced magnetic resonance imaging

Sentinel node biopsy during thoracolaparoscopic esophagectomy for advanced esophageal cancer

Background

Omitting extensive lymph node dissection could reduce esophagectomy morbidity in patients without lymph node metastases. Sentinel node biopsy may identify abdominal or thoracic lymph node metastases, thereby differentiating treatment. Feasibility of this approach was investigated in Western European esophageal cancer patients with advanced disease, without lymph node metastases at diagnostic work-up.

Methods

The sentinel node biopsy was performed in eight esophageal cancer patients with cT1-3N0 disease. One day pre-operatively, Tc-99m-labeled nanocolloid was endoscopically injected around the tumor. Lymphoscintigraphy was performed 1 and 3 h after injection. All patients underwent robotic thoracolaparoscopic esophagectomy with two-field lymph node dissection. Intraoperatively, sentinel nodes were detected by gamma probe. The resection specimen was analyzed for remaining activity by scintigraphy and gamma probe.

Results

Visualization rates of lymphoscintigraphy 1 and 3 h after tracer injection were 88 and 100 %, respectively. Intraoperative identification rate was 38 %. Postoperative identification was possible in all patients using the gamma probe to analyze the resection specimen. In 5/8 patients, lymph node metastases were found at histopathology, none of which was detected by the sentinel node biopsy. No adverse events related to the sentinel node biopsy were observed.

Conclusions

In our advanced esophageal cancer patients who underwent thoracolaparoscopic esophagectomy, the sentinel node biopsy did not predict lymph node status. Probably the real sentinel node could not be identified due to localization adjacent to the primary tumor or bypassing due to metastatic tumor involvement. Therefore, we consider the sentinel node biopsy not feasible in advanced esophageal cancer.

Estimating the need for neck lymphadenectomy in submucosal esophageal cancer using superparamagnetic iron oxide-enhanced magnetic resonance imaging: clinical validation study

BACKGROUND

In cases of thoracic esophageal cancer, multidirectional lymphatic flow from the tumor means that lymph node metastasis can occur in an area extending from the neck to the abdomen. To validate a method for limiting the performance of three-field lymphadenectomy only to patients who need it, we carried out a prospective study in which superparamagnetic iron oxide (SPIO)-enhanced lymphatic mapping was used to determine whether to perform neck lymph node dissection in patients with submucosal thoracic esophageal cancer.

METHODS

A total of 22 patients with clinically submucosal thoracic squamous cell esophageal cancer, without neck lymph node metastasis, were enrolled. SPIO was endoscopically injected into the peritumoral submucosal layer, after which its appearance in lymph nodes in the neck was evaluated using magnetic resonance imaging (MRI). Neck lymph nodes were then dissected based on the SPIO-enhanced MRI lymphatic mapping.

RESULTS

Influx of SPIO into lymph nodes was detected in 21 patients (95% detection rate). SPIO flowed to the neck in 8 (36%) patients. Influx of SPIO into neck lymph nodes was unilateral in five patients and bilateral in three patients, and the lymph nodes were dissected accordingly. A cancer-involved node was identified in two of those patients. In 14 patients, we did not dissect neck nodes. Patients were followed up for 6 to 47 months. The neck lymph node recurrence rate was zero, and the overall recurrence rate was 5%.

CONCLUSIONS

SPIO-enhanced lymphatic mapping may be useful for estimating the need for three-field lymphadenectomy with neck dissection.

Status of involved lymph nodes and direction of metastatic lymphatic flow between submucosal and t2-4 thoracic squamous cell esophageal cancers

BACKGROUND

Three-field lymph node dissection for thoracic esophageal cancer is associated with high morbidity and reduced quality of life after surgery. Consequently, minimized lymphadenectomy would be desirable, if appropriate. In the present study, we retrospectively analyzed the status of involved nodes and the direction of metastatic lymphatic flow from tumors into involved nodes to determine whether submucosal squamous cell esophageal cancers are potential candidates for minimized lymphadenectomy.

METHODS

We enrolled 199 patients who received esophagectomy with extensive lymph node dissection between 1989 and 2005 and retrospectively analyzed their prognoses, distribution of solitary metastatic lymph nodes, and the direction of metastatic lymphatic flow from the tumor, taking into consideration tumor location and depth.

RESULTS

Of these patients with submucosal cancers, 83% had 1 or 2 involved nodes, and their esophageal cancer-specific 5-year survival rate was 66%. Solitary lymph node metastasis did not occur in neck lymph nodes in lower thoracic submucosal esophageal cancers, and the direction of metastatic lymphatic flow from the tumor was almost always in one direction. By contrast, T2-4 cancers with 2-4 involved nodes had bidirectional metastatic lymphatic flow from the tumor.

CONCLUSIONS

There was a difference in the status of lymph node metastasis and the direction of metastatic lymphatic flow from tumors into involved nodes between submucosal and T2-4 thoracic squamous cell esophageal cancers. This analysis may be useful for developing an approach to minimized lymphadenectomy for thoracic esophageal cancers.

Preoperative mapping of lymphatic drainage from the tumor using ferumoxide-enhanced magnetic resonance imaging in clinical submucosal thoracic squamous cell esophageal cancer

BACKGROUND

In thoracic esophageal cancer, lymph node metastases distribute widely from the neck to the abdominal area as a result of a complex periesophageal lymphatic network. The aim of the present study was to evaluate the potential clinical utility of a new method of mapping lymphatic drainage from tumors using ferumoxide-enhanced magnetic resonance imaging (MRI).

METHODS

Twenty-three patients with clinical submucosal thoracic squamous cell esophageal cancer were examined. Ferumoxides were injected endoscopically into the peritumoral submucosal layer, after which their appearance in the lymph nodes in the neck, superior mediastinum, and abdomen was evaluated using MRI.

RESULTS

Flux of ferumoxides from tumors was detected in all 23 patients. Among the 20 patients with middle and lower thoracic esophageal cancers, there was no lymphatic drainage to the neck in 5 (25%) patients, none to the neck and superior mediastinum in 4 (20%), and none to the abdomen in 2 (10%), which could enable the extent of lymph node dissection to be reduced. We diagnosed clinical negative lymph node metastasis (N0) in 17 patients; the remaining 6 patients were diagnosed with clinical lymph node metastasis. Two patients (12%) diagnosed clinical N0, showed pathologic lymph node metastasis. Ferumoxide-enhanced MRI detected an influx of contrast agent into the metastatic node in both patients.

CONCLUSIONS

Ferumoxide-enhanced MRI lymphatic mapping enables detection of the direction and area of lymphatic flux. It thus has the potential to improve our ability to gauge the appropriate extent of treatment in clinical submucosal squamous cell esophageal cancer.

Visualization of lymphatic basin from the tumor using magnetic resonance lymphography with superparamagnetic iron oxide in patients with thoracic esophageal cancer

OBJECTIVE

To evaluate magnetic resonance (MR) lymphography with submucosal injection of superparamagnetic iron oxide (SPIO) for imaging lymphatic pathways from thoracic esophageal cancer.

METHODS

In 24 patients with esophageal cancer, SPIO was injected into the submucosal layer of the peritumoral region endoscopically and MR lymphography was conducted. In study 1, fast spoiled gradient-recalled acquisition using a steady-state (FSPGR) sequence was performed from the neck to the upper abdomen before and at 20, 40, and 60 minutes after injection in 10 patients. In study 2, FSPGR and spin echo T1-weighted images were obtained after injection in 14 patients. Areas scanned were the neck to the upper mediastinum and the upper abdomen.

RESULTS

In study 1, at 20 minutes after injection, the signal of each lymph node appeared attenuated when compared with precontrast images. The signal-to-noise ratio in lymph nodes exhibiting influx of SPIO was significantly lower than that found on precontrast images (P < 0.0005). In study 2, influx to the neck lymph nodes was detected in 8 patients (64.3%), whereas influx to the upper abdominal lymph nodes was detected in 13 (92.9%).

CONCLUSIONS

Magnetic resonance lymphography with SPIO could visualize the lymphatic pathways draining from the injection site and the location of lymph nodes exhibiting influx of SPIO in patients with thoracic esophageal cancer.

Diagnostic precision of nanoparticle-enhanced MRI for lymph-node metastases: a meta-analysis

BACKGROUND

At present, there is no accepted, ideal imaging modality or technique for diagnosis of lymph-node metastases. We aimed to assess the diagnostic precision of MRI with ferumoxtran-10-an ultrasmall superparamagnetic iron-oxide nanoparticle used as a contrast agent for diagnosis of lymph-node metastases, compared with that of unenhanced MRI and final histological diagnosis.

METHODS

We did a meta-analysis of prospective studies that compared MRI, with and without ferumoxtran-10, with histological diagnosis after surgery or biopsy. Sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated for every study; summary receiver operating characteristic (ROC) and subgroup analyses were done; and study quality and heterogeneity were assessed. Metaregression analysis was used to analyse the effect of ferumoxtran-10 in diagnostic precision of MRI.

FINDINGS

Summary ROC curve analysis for per-lymph-node data showed an overall sensitivity of 0.88 (95% CI 0.85-0.91) and overall specificity of 0.96 (0.95-0.97) for ferumoxtran-10-enhanced MRI. Overall weighted area under the curve for ferumoxtran-10-enhanced MRI was 0.96 (SE 0.01), DOR 123.05 (95% CI 5.93-256.93). Unenhanced MRI had less overall sensitivity (0.63 [0.57-0.69]) and specificity (0.93 [0.91-0.94]), with an overall weighted area under the ROC curve of 0.84 (SE 0.11) and DOR of 26.75 (95% CI 8.48-84.42). Significant heterogeneity was noted for studies reporting enhanced MRI and unenhanced MRI. Metaregression analysis confirmed the significant effect of ferumoxtran-10 in the diagnostic precision of MRI (p=0.001).

INTERPRETATION

Ferumoxtran-10-enhanced MRI is sensitive and specific in detection of lymph-node metastases for various tumours. It offers higher diagnostic precision than does unenhanced MRI for detection of lymph-node metastases, and allows functional and anatomical definition when used as an imaging modality.

Diagnostic radiology and nuclear medicine

The diagnosis and accurate staging of esophageal adenocarcinoma remains one of the greatest challenges for non-invasive imaging techniques. All modalities have limitations and require a rational application of combined tools in order to assess the extent of loco-regional tumor and distant metastatic disease. The fundamental role remains defining organ-confined disease and mapping non-organ confined disease. Endoscopic ultrasound combined with multislice computed tomography (CT) is the mainstay of morphologic loco-regional staging. In recent years, functional metabolic 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) has emerged as a particularly useful adjunct to detect occult metastatic disease, to predict response to neoadjuvant therapy and to document recurrent disease. The current imaging algorithm and new developments in imaging assessment will be reviewed.