Sentinel lymph nodes with technetium-99m colloidal rhenium sulfide in patients with esophageal carcinoma

Near-infrared fluorescence imaging-guided lymphatic mapping in thoracic esophageal cancer surgery

PURPOSE

Identifying the lymphatic drainage pathway is important for accurate lymph node (LN) dissection in esophageal cancer (EC). This study aimed to assess lymphatic drainage mapping in thoracic EC using near-infrared fluorescent (NIRF) imaging with indocyanine green (ICG) and identify its feasibility for intraoperative LN drainage visualization and dissection.

METHODS

From November 2019 to August 2020, esophagectomy was performed using intraoperative NIRF navigation with ICG injected into the esophageal submucosa by endoscopy. All LNs were divided into four groups according to the NIRF status and presence of metastasis: NIRF⁺LN⁺, NIRF⁺LN^-, NIRF^-LN⁺, and NIRF^-LN^-.

RESULTS

Regional LNs were detected in all 84 enrolled patients with thoracic EC. A total of 2164 LNs were removed, and the mean number of dissected LNs was 25.68 ± 12.00. NIRF⁺ LNs were observed in all patients and distributed at 19 LN stations, which formed lymphatic drainage maps. The top five LN stations of NIRF⁺ probability in upper thoracic EC were No. 7, 106ecR, 107, 1, and 106recL; in middle thoracic EC, they were No. 107, 7, 110, 1, and 105; and in lower thoracic EC, they were No. 107, 7, 110, 106recR, and 1. There were no cases of ICG-related adverse events or chylothorax. The 30-day mortality rate was 0%. Major complications included anastomotic fistula (7.14%), pneumonia (4.76%), pleural effusion (13.10%), atelectasis (3.75%), hoarseness (8.33%), and arrhythmia (4.76%).

CONCLUSION

Regional LN mapping of thoracic EC was performed using ICG/NIRF imaging, which showed different preferred LN drainage stations in various anatomical locations of the thoracic esophagus. ICG/NIRF imaging is feasible for intraoperative LN drainage visualization and dissection.

CLINICAL TRIAL REGISTRATION

The clinical trial registration number is NCT04173676 ( http://www.clinicaltrials.gov/ ).

Preoperative detection of sentinel lymph nodes with hybrid SPECT/computed tomography imaging may improve the accuracy of sentinel lymph node biopsies in patients with early stages of cancer of the oesophagus or gastro-oesophageal junction

Objectives

The aim of this study was to investigate the sentinel lymph node biopsy (SLNB) method in patients with cancer of the oesophagus or gastro-oesophageal junction (GOJ) guided by preoperative hybrid single-photon emission tomography/computed tomography (SPECT/CT) lymphoscintigraphy.

Methods

Thirty-nine patients with stage T1–T3, any N-stage, M0 cancer of the oesophagus or GOJ planned for curatively intended esophagectomy underwent preoperative SPECT/CT lymphoscintigraphy following endoscopically guided submucosal injection of radiocolloid and intraoperative radio-guided SLNB using a hand-held gamma scintillation device.

Results

The detection rate in preoperative SPECT/CT imaging was 88%. The median number of detected SLN stations in preoperative imaging was 1 (range 0–4). At least one suspected SLN was identified in all intraoperative SLNP procedures. In six cases, no lymph nodes were identified in the SLNB. In six cases, the SLNB was false negative. The sensitivity for successful SLNB procedures was 20%, the specificity was 100% and the accuracy was 75%.

Conclusions

Preoperative SLN mapping using SPECT/CT yields a high number of detected SLN stations compared to previous studies using planar imaging. The accuracy of the SLNB method in patients with predominantly ≥T3-stage tumours and with a history of previous neoadjuvant treatment is poor, and the method is not recommended in these patient groups.

Rhenium Sulfide Nanoparticles as a Biosafe Spectral CT Contrast Agent for Gastrointestinal Tract Imaging and Tumor Theranostics in Vivo

Spectral computed tomography (CT) imaging as a novel imaging technique shows promising prospects in the accurate diagnosis of various diseases. However, clinically iodinated contrast agents suffer from poor signal-to-noise ratio, and emerging heavy-metal-based CT contrast agents arouse great biosafety concern. Herein, we show the fabrication of rhenium sulfide (ReS₂) nanoparticles, a clinic radiotherapy sensitizer, as a biosafe spectral CT contrast agent for the gastrointestinal tract imaging and tumor theranostics in vivo by teaching old drugs new tricks. The ReS₂ nanoparticles were fabricated in a one-pot facile method at room temperature, and exhibited sub-10 nm size, favorable monodispersity, admirable aqueous solubility, and strong X-ray attenuation capability. More importantly, the proposed nanoparticles possess an outstanding spectral CT imaging ability and undoubted biosafety as a clinic therapeutic agent. Besides, the ReS₂ nanoparticles possess appealing photothermal performance due to their intense near-infrared absorption. The proposed nano-agent not only guarantees obvious contrast enhancement in gastrointestinal tract spectral CT imaging in vivo, but also allows effective CT imaging-guided tumor photothermal therapy. The proposed "teaching old drugs new tricks" strategy shortens the time and cuts the cost required for clinical application of nano-agents based on existing clinical toxicology testing and trial results, and lays down a low-cost, time-saving, and energy-saving method for the development of multifunctional nano-agents toward clinical applications.

Sentinel node navigation surgery in esophageal cancer

Over the last 20 years, the sentinel node (SN) concept has been widely applied to the surgical staging of both breast cancer and melanoma. However, the validity of this concept has been controversial for esophageal cancer, because SN mapping for esophageal cancer is not considered to be technically easy because of the complicated multidirectional lymphatic networks of the esophagus and mediastinum. Nevertheless, studies including meta-analyses indicated that SN mapping may be feasible in early esophageal cancer. Transthoracic esophagectomy with three-field lymphadenectomy was developed as a potential curative procedure for thoracic esophageal cancer. However, this highly invasive procedure might increase morbidity and reduce patients' quality of life (QOL) after esophagectomy. Although further validation based on multicenter trials using the standard protocol of SN mapping for esophageal cancer is required, SN navigation surgery would enable us to carry out personalized and limited lymph node dissection which might reduce morbidity and maintain patients' QOL.

Update on the indications and results of sentinel node mapping in upper GI cancer

The clinical utilization of sentinel node (SN) mapping for early esophageal cancer or gastric cancer has been unclear for a long time. However, previous investigations regarding SN mapping of these cancers have shown relatively good results with regard to the detection rate and diagnostic accuracy for determining the lymph node status. SN mapping helps obtain information about individual metastatic status and allows the modification of the operation in early-stage upper gastrointestinal (GI) disease. Radio-guided methods for identifying SNs in early esophageal cancer have been established via endoscopic injection of technetium-99m tin colloid. Previous studies have reported that the SN concept seems valid, and radio-guided SN mapping can be feasible in cT1N0 esophageal cancer. SN navigation surgery are believed to have potential as strategies for minimally invasive modified surgery for early esophageal cancer. A Japanese study group conducted a prospective multicenter trial of SN mapping for early gastric cancer using a dual tracer method with radioactive colloid and blue dyes; they demonstrated a high detection rate and accuracy for determining the metastatic status based on SN mapping. Subsequently, minimized gastrectomy, including partial gastrectomy and segmental gastrectomy with individualized selective and modified lymphadenectomy for early gastric cancer with a negative SN has been performed to evaluate the long-term survival and postoperative quality of life (QOL) in a multicenter prospective trial. This study verified the SN concept in early-stage upper GI disease with cN0 and found that function-preserving esophagectomy or gastrectomy may help maintain patients' post-surgical QOL.

Liquid Exfoliation of Colloidal Rhenium Disulfide Nanosheets as a Multifunctional Theranostic Agent for In Vivo Photoacoustic/CT Imaging and Photothermal Therapy

Near-infrared light-mediated theranostic agents with superior tissue penetration and minimal invasion have captivated researchers in cancer research in the past decade. Herein, a probe sonication-assisted liquid exfoliation approach for scalable and continual synthesis of colloidal rhenium disulfide nanosheets, which is further explored as theranostic agents for cancer diagnosis and therapy, is reported. Due to high-Z element of Re (Z = 75) and significant photoacoustic effect, the obtained PVP-capped ReS₂ nanosheets are evaluated as bimodality contrast agents for computed tomography and photoacoustic imaging. In addition, utilizing the strong near-infrared absorption and ultrahigh photothermal conversion efficiency (79.2%), ReS₂ nanosheets could also serve as therapeutic agents for photothermal ablation of tumors with a tumor elimination rate up to 100%. Importantly, ReS₂ nanosheets show no obvious toxicity based on the cytotoxicity assay, serum biochemistry, and histological analysis. This work highlights the potentials of ReS₂ nanosheets as a single-component theranostic nanoplatform for bioimaging and antitumor therapy.

Near-Infrared Lymphatic Mapping of the Recurrent Laryngeal Nerve Nodes in T1 Esophageal Cancer

BACKGROUND

It is still unclear that dissection of recurrent laryngeal nerve nodes is mandatory in patients with cT1 middle or lower thoracic esophageal squamous cell carcinoma when the nodes are negative in preoperative staging workup. We aimed to evaluate the feasibility of near-infrared image-guided lymphatic mapping of bilateral recurrent laryngeal nerve nodes.

METHODS

The day before operation, we injected indocyanine green (ICG) into the submucosal layer by endoscopy. At the time of upper mediastinal dissection, ICG-stained basins were identified along the bilateral recurrent laryngeal nerves and retrieved under guidance of the Firefly system. After the operation, remnant ICG-unstained basins were dissected from the specimen to assess the presence of metastasis.

RESULTS

Of 29 patients enrolled, ICG-stained basins could be identified in 25 patients (86.2%), and 6 of them (24.0%) had nodal metastasis; 4 in the right recurrent laryngeal nerve chain, 1 in the left recurrent laryngeal nerve chain, and 1 in both recurrent laryngeal nerve chains. On pathologic examination of 345 recurrent laryngeal nerve nodes, two metastatic nodes were identified in ICG-unstained basins along the left recurrent laryngeal nerve in a patient who had lymph node metastases in ICG-stained basins along both recurrent laryngeal nerves. Negative predictive value in detection of nodal metastasis was 100% for the right recurrent laryngeal nerve chain and 98.2% for the left recurrent laryngeal nerve chain.

CONCLUSIONS

Real-time assessment of recurrent laryngeal nerve nodes with near-infrared image was technically feasible, and we could detect lymphatic basins that most likely have nodal metastasis. Our technique might be useful in determining the optimal extent of lymphadenectomy.

Identification of the Lymphatic Drainage Pattern of Esophageal Cancer with Near-Infrared Fluorescent Imaging

OBJECTIVE

Nodal status is one of the most important long-term prognostic factors for esophageal cancer. The aim of this study was to evaluate the ability of near-infrared (NIR) light fluorescent imaging to identify the lymphatic drainage pattern of esophageal cancer.

METHODS

Patients with distal esophageal cancer or esophagogastric junction cancer scheduled for esophagectomy were enrolled in this study. Before surgery, an endoscopy was performed with submucosal injection of 2 cc of indocyanine green (ICG) around the tumor. Real-time NIR images from the surgical field were obtained for each patient to visualize the lymphatic ICG drainage.

RESULTS

A total of nine patients were included in this study. Ivor Lewis esophagectomy was performed in all cases. ICG drainage was visualized to first drain along the left gastric nodes in eight patients (88.9%) and toward the diaphragmatic nodes in one patient (11.1%). The median number of resected nodes was 32. Three patients (33.3%) presented nodal involvement. All of them had positive nodes in the first nodal station identified with ICG.

CONCLUSIONS

Evaluation of the lymphatic drainage pattern with real-time NIR light fluorescent technique is feasible. Distal and esophagogastric junction tumors showed to drain first in the left gastric nodes in most of the cases.

Stage-directed individualized therapy in esophageal cancer

Esophageal cancer is the eighth most common cancer worldwide, and the incidence of esophageal carcinoma is rapidly increasing. With the advent of new staging and treatment techniques, esophageal cancer can now be managed through various strategies. A good understanding of the advances and limitations of new staging techniques and how these can guide in individualizing treatment is important to improve outcomes for esophageal cancer patients. This paper outlines the recent progress in staging and treatment of esophageal cancer, with particularly attention to endoscopic techniques for early-stage esophageal cancer, multimodality treatment for locally advanced esophageal cancer, assessment of response to neoadjuvant treatment, and the role of cervical lymph node dissection. Furthermore, advances in robot-assisted surgical techniques and postoperative recovery protocols that may further improve outcomes after esophagectomy are discussed.

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.

Sentinel lymph node in oesophageal cancer-a systematic review and meta-analysis

BACKGROUND

Sentinel lymph nodes (SLNs) have been used to predict regional lymph node metastasis in patients with melanoma and breast cancer. However, the validity of the SLN hypothesis is still controversial for oesophageal cancer. We performed this meta-analysis to evaluate the feasibility and accuracy of radio-guided SLN mapping for oesophageal cancer.

METHODS

A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google scholar, Science Direct, and Web of Science. Original data was abstracted from each study and used to calculate a pooled event rates and 95% confidence interval (95% CI).

RESULTS

The search identified 23 relevant articles. The overall detection rate was 0.93 (95% CI: 0.894-0.950), sensitivity 0.87 (95% CI: 0.811-0.908), negative predictive value 0.77 (95% CI: 0.568-0.890) and the accuracy was 0.88 (95% CI: 0.817-0.921). In the adenocarcinoma cohort, detection rate was 0.98 (95% CI: 0.923-0.992), sensitivity 0.84 (95% CI: 0.743-0.911) and the accuracy was 0.87(95% CI: 0.796-0.913). In the squamous cell carcinoma group, detection rate was 0.89 (95% CI: 00.792-0.943), sensitivity 0.91 (95% CI: 0.754-0.972) and the accuracy was 0.84 (95% CI: 0.732-0.914).

CONCLUSIONS

It is possible to identify and obtain a SLN before neoadjuvant therapy in oesophageal cancer. However, further work is needed to optimize radiocolloid type, refine the technique and develop a quick and accurate way to determine SLN status intraoperatively. This technique has to be further evaluated before it can be applied widely.

Minimally invasive surgery for esophageal cancer: a review on sentinel node concept

BACKGROUND

Lymphoadenectomy is a cornerstone of esophageal cancer treatment, and sentinel node (SN) biopsy (SNB) might provide surgeons with an extra tool to limit unnecessarily extended lymphadenectomy and to implement a minimally invasive approach. The aim of our study was to review all the available literature on the use of SNB in esophageal surgery for malignancy.

METHODS

The review was conducted according to the PRISMA guidelines. A systematic search was performed in PubMed, EMBASE, and the Cochrane database to identify all original articles on the role of SNB in esophageal cancer. Data on methodologies, tumor stage and localization, and results were summarized and used to address relevant clinical questions related to the application of the SNB technique in esophageal cancer.

RESULTS

Twelve studies were included, with a total of 492 patients. Different methods for SN identification were used (radionuclide, blue dye, computed tomography [CT] lymphography). The pooled values estimated using the random-effects model were, respectively: technetium-99 m overall detection rate (DR) 0.970 (95 % CI 0.814-0.996), accuracy (ACC) 0.902 (95 % CI 0.736-0.968); blue-dye DR 0.971 (95 % CI 0.890-0.993), ACC 0.790 (95 % CI 0.681-0.870); and CT lymphoscintigraphy DR 0.970 (95 % CI 0.814-0.996), ACC 0.902 (95 % CI 0.736-0.968).

CONCLUSION

Based on these results, the concept of SN in esophageal cancer is technically feasible with an acceptable DR and ACC, and it might be applicable in the event of early-stage adenocarcinoma of the gastroesophageal junction in patients with a high surgical risk or in a patient where an endoscopic resection is taken into consideration. Further studies focused on a single tumor type and localizations are needed in order to predict the correct utilization of this concept in minimally invasive treatment of esophageal cancer.

Accuracy of sentinel node biopsy in esophageal carcinoma: a systematic review and meta-analysis of the pertinent literature

The use of sentinel node surgery for esophageal carcinoma is still under investigation. We evaluated the data available in the literature on this topic, and herein present the results in a systematic review format. PUBMED, SCOPUS, the ISI web of knowledge and the information from the annual meetings of the Japan Esophageal Society were searched using the search terms: "(esophagus OR esophageal) AND sentinel". The outcomes of interest were the detection rate and sensitivity. Overall, 18 studies were included. The pooled detection rate was 89.2% [82.6-93.5]. Patients with T1 and two tumors had a 17% higher detection rate compared to those with T3 and four tumors. The pooled sensitivity was 84% [78-88%]. The sensitivity was higher for adenocarcinoma compared to squamous cell carcinoma (SCC) (91 vs. 81%). In the SCC patients, there was a trend toward decreased sensitivity associated with an increasing tumor depth (T1:88%, T2:76%, T3:50%). Our analysis indicated that sentinel node biopsy is useful in adenocarcinoma patients. For SCC patients, including only cN0 patients (preferably T1 and 2) would increase the detection rate and sensitivity. Due to the limited number of high-quality studies, drawing any more definite conclusions is impossible. Large cohort studies with a standardized and consistent design will be needed in the future.

Sentinel node navigation surgery in early-stage esophageal cancer

The sentinel node (SN) concept has revolutionized the surgical staging of both melanoma and breast cancer over the past two decades. However, the validity of the SN hypothesis has been controversial for esophageal cancer, because SN mapping for esophageal cancer is technically complicated, and the number of early-stage esophageal cancer is very limited. Nevertheless previous studies nicely demonstrated that SN mapping may be feasible in patients with early-stage esophageal cancer. Transthoracic extended esophagectomy with three-field radical lymph node dissection has been recognized as a curative procedure for thoracic esophageal cancer in Japan. However, uniform application of this highly invasive procedure might increase the morbidity and markedly reduce the quality of life (QOL) after surgery. Although further accumulation of evidence based on multicenter clinical trials using a standard protocol is needed, SN mapping and SN navigation surgery would provide significant information to perform individualized selective lymphadenectomy which might reduce the morbidity and retain the patients' QOL. In addition, technical innovation including the development of new tracers is expected to confirm the accuracy and reliability of SN mapping in esophageal cancer.

Sentinel lymph node biopsy in esophageal cancer: should it be standard of care?

INTRODUCTION

Sentinel node mapping is established in some superficial cancers but remains controversial in harder-to-access solid tumors. There are an increasing number of recent studies suggesting that isolated tumor cells have prognostic significance in predicting poor survival, in breast cancer, esophageal cancer, and others. It is for this reason that we have persevered with the sentinel lymph node concept in our esophagectomy cancer patients, and we report our results since 2008.

METHODS

Thirty-one of 32 consecutive patients underwent resection for invasive esophageal cancer along with sentinel lymph node retrieval (resection rate, 97%). Peritumoral injection of (99m)Tc antimony colloid was performed by upper endoscopy prior to the operation. A two-surgeon synchronous approach via a right thoracotomy and laparotomy was performed with a conservative lymphadenectomy. Sentinel lymph nodes were identified with a gamma probe both in and ex vivo, and sent off separately for three serial sections and immunohistochemistry with AE1/AE3.

RESULTS

The median patient age was 63.4 years (range, 45-75 years). Most patients (81%) had an adenocarcinoma, and 61% had received neoadjuvant therapy. At least one sentinel lymph node (median, 3) was identified in 29 of 31 patients (success rate, 94%). Sentinel nodes were present in more than one nodal station in 16 patients (55%). One false negative case led to a sensitivity of 90%. In 28 of 29 patients, the sentinel lymph node accurately predicted findings in non-sentinel nodes (accuracy, 96%).

CONCLUSIONS

Sentinel lymph node biopsy is both feasible and accurate in esophageal resections with conservative lymphadenectomy. It allows targeted serial sectioning and immunohistochemical studies of those nodes and should become standard of care in patients undergoing esophagectomy for esophageal cancer.

Barrett's esophagus: treatments of adenocarcinomas II

The following topics are explored in this collection of commentaries on treatments of adenocarcinomas related to Barrett's esophagus: the importance of intraoperative frozen sections of the margins for the detection of high dysplasia; the preferable way for sentinel node dissection; the current role of robotic surgery and of video-endoscopic approach; the value of the Siewert's classification of adenocarcinomas; the indications of two-step esophagectomy; the evaluation of pathological complete response; the role of PET scan in staging and response assessment; the role of p53 in the selection of adenocarcinomas patients; chemotherapy regimens for adenocarcinomas; the use of monoclonal antibodies in the control of cell proliferation; he attempt to define a stage-specific strategy, and the possible indications of selective therapy; and changes in mortality rates from esophageal cancer.

Sentinel node navigation surgery is acceptable for clinical T1 and N0 esophageal cancer

BACKGROUND

If the sentinel node (SN) concept is established for esophageal cancer, it will be possible to reduce safely the extent of lymphadenectomy. Our objective was to perform SN mapping in esophageal cancer to assess distribution of lymph node metastases with the goal to reduce the need for extensive lymphadenectomy.

METHODS

A total of 134 patients who underwent esophagectomy with lymph node dissection were enrolled. The number of patients with clinical T1, T2, and T3 tumors was 60, 31, and 32, respectively. Eleven patients also received neoadjuvant chemoradiation therapy (CRT). (99m)Tc-Tin colloid was injected endoscopically into the esophageal wall around the tumor 1 day before surgery. SNs were identified by using radioisotope (RI) uptake. RI uptake of all dissected lymph nodes was measured during and after surgery. Lymph node metastases, including micrometastases, were confirmed by hematoxylin eosin and immunohistochemical staining.

RESULTS

Detection rates of SNs were 93.3% in cT1, 100% in cT2, 87.5% in cT3, and 45.5% in CRT patients. In the 120 cases where SNs were identified, lymph node metastases were found in 12 patients with cT1, 18 with cT2, 24 with cT3 tumors, and 3 with CRT. Accuracy rate of SN mapping was 98.2% in cT1, 80.6% in cT2, 60.7% in cT3, and 40% in CRT patients. Although one false-negative case had cT1 tumor, the lymph node metastasis was detected preoperatively.

CONCLUSIONS

SN mapping can be applied to patients with cT1 and cN0 esophageal cancer. SN concept might enable to perform less invasive surgery with reduction of lymphadenectomy.

Sentinel node identification using technetium-99m neomannosyl human serum albumin in esophageal cancer

BACKGROUND

This study is a clinical trial designed to test the reliability and feasibility of sentinel node detection using a new mannose receptor radioactive binding agent in patients with esophageal squamous cell carcinoma.

METHODS

Twenty-three patients (21 men, 2 women; mean age 61.0±8.60 years) who were candidates for esophagectomy with conventional lymph node dissection for thoracic esophageal cancer were enrolled. A total dose of 1 mCi of 99mTc-MSA [technetium-99m neomannosyl human serum albumin] in 0.2 mL was administered at 4 quadrants into the submucosal layer around the primary tumor under esophagoscopic guidance approximately 1 hour before surgery. Intraoperative sentinel node sampling was subsequently followed by esophagectomy. All harvested lymph nodes were cut into 2-mm slices and ultimately diagnosed using formalin-fixed and paraffin-embedded sections with hematoxylin and eosin staining.

RESULTS

The number of dissected lymph nodes per patient was 30.5±9.18 (15-47). Among 23 patients, the sentinel lymph nodes could be identified in 21 patients (91.3%). The sentinel nodes could be identified in all 21 patients with cT1 or T2N0M0 (100%) disease; these patients were candidates for sentinel lymph node navigation surgery for the esophageal cancer. The mean number of sentinel nodes identified was 2.6±1.35 (range, 1-5) per patient. No false-negative sentinel lymph nodes were detected in any of the 8 patients with node-positive disease (0%).

CONCLUSIONS

Intraoperative sentinel lymph node identification using 99mTc-MSA was feasible and reliable in patients with esophageal squamous cell carcinoma.

Feasibility study of sentinel lymph node biopsy in esophageal cancer with conservative lymphadenectomy

INTRODUCTION

Lymphoscintigraphy and sentinel node mapping is established in breast cancer and melanoma but not in esophageal cancer, even though many centers have shown that occult tumor deposits in lymph nodes influence prognosis. We report our initial experience with lymphoscintigraphy and sentinel lymph node biopsy in patients undergoing resection for esophageal cancer.

METHODS

Sixteen of 17 consecutive patients underwent resection for invasive esophageal cancer along with sentinel lymph node retrieval (resection rate, 94%). Peritumoral injection of (99m)Tc antimony colloid was performed by upper endoscopy prior to the operation. A two-surgeon synchronous approach via right thoracotomy and laparotomy was performed with conservative lymphadenectomy. Sentinel lymph nodes were identified using a gamma probe both in vivo and ex vivo. Sentinel lymph nodes were sent off separately for serial sections and immunohistochemistry.

RESULTS

Median patient age was 60.4 years (range, 45-75 years). Fifteen were male, and thirteen had adenocarcinoma. At least one sentinel lymph node (median, 2) was identified in 14 of 16 patients (success rate, 88%). Sentinel nodes were present in more than one nodal station in five patients (31%). In all 14 patients, the sentinel lymph node accurately predicted findings in non-sentinel nodes (accuracy, 100%). Three patients with positive sentinel lymph nodes had metastases identified in non-sentinel nodes (sensitivity, 100%).

CONCLUSIONS

Sentinel lymph node biopsy is feasible in esophageal resection with conservative lymphadenectomy, and initial results suggest it is accurate in predicting overall nodal status. Further study is needed to assess impact on patient management and prognosis.

Impact of lymph-node metastasis site in patients with thoracic esophageal cancer

BACKGROUND AND OBJECTIVES

We retrospectively compared surgical outcomes between patients with intra-thoracic and extra-thoracic (cervical and abdominal) lymph-node metastasis.

METHODS

The study population comprised 96 patients with lymph-node metastasis who had undergone curative esophagectomy for thoracic esophageal cancer. The patients were grouped according to whether the site of lymph-node metastasis was intra-thoracic, extra-thoracic, or both intra-thoracic and extra-thoracic. The patient characteristics, survival time, and prognostic factors were compared.

RESULTS

The most significant difference in disease-specific survival was detected at a threshold value of four metastatic lymph nodes. Lymph-node metastasis was observed at intra-thoracic sites in 41 patients, at extra-thoracic sites in 20 patients, and at both intra-thoracic and extra-thoracic sites in 35 patients. Intra-thoracic lymph-node metastasis was frequently observed in patients with middle and upper thoracic esophageal cancer. There was no difference in the number of metastatic lymph nodes between patients with intra-thoracic and extra-thoracic lymph-node metastasis. Multivariate analysis revealed that the number of metastatic lymph nodes was an independent prognostic factor, whereas the site of metastatic lymph nodes was not.

CONCLUSIONS

These findings suggest that the surgical outcomes in patients with thoracic esophageal cancer depend on the number, but not the site, of metastatic lymph nodes after curative esophagectomy.

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology.

Management of early esophageal cancer

In early esophageal cancer, squamous cell cancer and early adenocarcinoma must be managed differently because they have different origins, pathogenesis. and clinical characteristics. The current treatment options vary widely, from extended resection with lymphadenectomy to endoscopic mucosectomy or ablation. None of these treatment options can be recommended universally. Instead, an individualized strategy should be based on the depth of tumor infiltration into the mucosa or submucosa, the presence or absence of lymph node metastases, the multicentricity of tumor growth, the length of the segment of intestinal metaplasia, and comorbidities of the patient. Endoscopic mucosectomy may be sufficient in a subset of patients who have m1 or m2 squamous cell carcinoma and in patients who have isolated foci of high-grade intraepithelial neoplasia or mucosal cancer. Surgical resection is the treatment of choice for carcinomas invading the submucosal and multicentric tumors. Limited resection with jejunal interposition provides an effective treatment option for patients who have early esophageal adenocarcinoma. The onset of lymph node involvement is later in patients who have early adenocarcinoma than in patients who have squamous cell cancer, probably because chronic injury and repair mechanisms obliterate the otherwise abundant lymph vessels.

Sentinel lymph node biopsy for gastrointestinal cancers

Sentinel lymph node biopsy (SLNB) in gastrointestinal-(GI)-tract cancer is not yet of clinical relevance. Nevertheless, the results in the upper GI-tract promise to be helpful to individualize the indication for surgical therapy. SLNB in colon cancer still fails to show high validity to predict the nodal status, but may be helpful to clarify the prognostic role of micrometastases/isolated tumor cells. In anal cancer SLNB is able to guide the indication for groin irradiation.

Extramural lymphatic drainage from the thoracic esophagus based on minute cadaveric dissections: fundamentals for the sentinel node navigation surgery for the thoracic esophageal cancers

In order to elucidate the lymphatic pathways from the thoracic esophagus, minute dissection of five adult cadavers, from the neck through the diaphragm, was performed. Peri-esophageal lymphatics were dissected from both the anterior and posterior aspects. The topographical differences between the right and left lymphatic drainage were revealed. The right lymphatic drainage system (RDS) was basically longitudinal and multi-stationed. Longitudinal lymphatics were relatively poorly developed in the left lymphatic drainage system (LDS), and direct drainage to the thoracic duct from the left wall of the thoracic esophagus, was frequently observed. The right uppermost thoracic paratracheal node received almost all levels of the right esophageal wall, and this node was thought to be the key node in the RDS. A contralateral lymphatic pathway was relatively frequently observed in the middle and lower thoracic esophagus. These results seemed to be in agreement with the anatomical and clinicopathological data in the literature, and might serve as a basis for sentinel node navigation surgery for the thoracic esophageal cancers.

Radio-guided sentinel node mapping in patients with superficial esophageal carcinoma: feasibility study

The aim of this study was to assess whether the sentinel node concept could be applicable to clinically early carcinoma of the esophagus. We studied ten consecutive cT1N0 patients who underwent radical esophagectomy with regional lymph node dissection. On the day before surgery, 99m-Tc tin colloid was injected endoscopically around the primary tumor. Lymphoscintigraphy was also performed about three hours after injection. Immediately after surgery, the radioactivity of all dissected lymph nodes was measured with a hand-held gamma probe. The radioactivity and the metastatic status assessed by routine histopathologic examination were compared. A total of six patients had hot spots detected by lymphoscintigraphy, of which the detection rate was 60% (6 of 10). The ex vivo hot node detection rate was 90% (9 of 10). Three patients were found to have metastatic nodes. In one patient, sentinel node mapping failed to identify any hot spot or hot node. In the other two patients, the metastatic nodes did not correspond to hot nodes. The accuracy of hot node status was 77.8% (7 of 9), and the false-negative rate was 100% (2 of 2). The present study showed that radio-guided sentinel node detection is insufficiently reliable at present due to the high false-negative rate and low accuracy.

Limited surgical resection and jejunal interposition for early adenocarcinoma of the distal esophagus

The need for radical resection and extensive lymphadenectomy for early adenocarcinoma of the distal esophagus has recently been challenged. Limited surgical resection and endoscopic mucosal ablation techniques are increasingly proposed and used as less invasive alternatives. Available data indicate that a limited resection of the distal esophagus and esophagogastric junction with jejunal interposition is associated with less morbidity and mortality, provides similar oncologic results, and offers a better quality of life as compared with radical esophagectomy. In contrast, endoscopic ablation and mucosectomy techniques are still plagued by high tumor recurrence rates, particularly in patients with incomplete removal of the underlying Barrett's mucosa, multicentric tumors, or tumors invading into the submucosa. Attention to technical details of limited resection and jejunal interposition is, however, required to avoid complications, poor functional results, and the need for reintervention.

Current status of sentinel lymph node navigation surgery in breast and gastrointestinal tract

Sentinel lymph node biopsy (SLNB) has been developed as a new diagnostic and therapeutic modality in melanoma and breast cancer surgery. The purpose of the SLNB include preventing the operative morbidity and improving the pathologic stage by focusing on fewer lymph nodes using immunocytochemic and molecular technology has almost achieved in breast cancer surgery. The prognostic meaning of immunocytochemically detected micrometastases is also evaluating in the SLN and bone marrow aspirates of women with early-stage breast cancer. SLNB using available techniques have suggested that the lymphatic drainage of the gastrointestinal tract is much more complicated than other sites, skip metastasis being rather frequent because of an aberrant lymphatic drainage outside of the basin exist. At the moment, the available data does not justify reduced extent of lymphadenectomy, but provides strong evidence for an improvement in tumor staging on the basis of SLNB. Two large scale prospective multi-center trials concerning feasibility of gamma-probe and dye detection for gastric cancer are ongoing in Japan. Recent studies have shown favorable results for identification of SLN in esophageal cancer. CT lymphography with endoscopic mucosal injection of iopamidol was applicable for SLN navigation of superficial esophageal cancer. The aim of surgical treatment is complete resection of the tumor-infiltrated organ including the regional lymph nodes. Accurate detection of SLN can achieve a selection of a more sophisticated tailor made approach. The patient can make a individualized choice from a broader spectrum of therapeutic options including endoscopic, laparoscopic or laparoscopy-assisted surgery, modified radical surgery, and typical radical surgery with lymph node dissection. Ultrastaging by detecting micrometastasis at the molecular level and the choice of an adequate treatment improve the postoperative quality of life and survival. However these issues require further investigation.

Sentinel node for gastrointestinal malignancies

Sentinel node (SN) concept is valid in gastrointestinal (GI) malignancies. The dual tracer method with radio-guided and dye-guided SN mapping is feasible in GI malignancies and is useful in detecting unexpected aberrant drainage routes from GI cancers. SN mapping enabled us to perform individualized and step-wise lymphadenectomy in patients with GI cancer. A combination of SN mapping and endoscopic surgery will contribute to the improvement in quality of life after surgical treatment of GI cancer.

Efficacy of different technical procedures for sentinel lymph node biopsy in gastric cancer staging

BACKGROUND

The clinical impact of sentinel lymph node biopsy (SLNB) in gastric cancer is controversial. We performed a prospective trial to compare different methods: radiocolloid method (RM), dye method (DM), and both methods simultaneously (dual method, or DUM) for reliability and therapeutic consequences.

METHODS

RM and DM were applied in 35 gastric cancer patients. After endoscopic peritumoral injection of (99m)Tc-colloid and Patent Blue V, the positions of all blue sentinel lymph nodes (SLNs) were recorded, and the SLNs microscopically examined by hematoxylin and eosin, step sections, and immunohistochemistry.

RESULTS

RM, DM, and DUM identified the SLNs in 34 (97%) of 35 patients. The sensitivity for the prediction of positive lymph node status for RM was 22 (92%) of 24, for DM 16 (66%) of 24, and for DUM 22 (92%) of 24. In 7 of 17 (RM), 5 of 15 (DM), and 7 of 17 (DUM) patients classified as N0 by routine hematoxylin and eosin staining, micrometastases or isolated tumor cells were found in the SLN (upstaging) after focused examination. If only a limited lymph node dissection of the SLN basins would have been performed in patients, residual lymph node metastases were left in 9 of 24 (RM), in 7 of 34 (DM), and in 5 of 24 (DUM) of patients with node-positive disease.

CONCLUSIONS

Use of RM was superior. DUM did not further increase the sensitivity. A limited lymph node dissection-i.e., lymphatic basin in patients with SLN-positive disease-is associated with a high risk of residual metastases. Patients with negative SLNs may be selected for a limited surgical procedure if they meet certain criteria.

Multispectral imaging autofluorescence microscopy in colonic and gastric cancer metastatic lymph nodes

BACKGROUND & AIMS

The lymphadenectomy and extended lymphadenectomy procedures have been points of controversy in surgical oncology. The methods available for the detection of metastatic lymph nodes are numerous. These include lymphoscintigraphy and radiolabeled antibody detection, but in most cancers the currently used technique is sentinel lymph node identification, performed primarily through the use of immunohistochemistry. We propose the application of autofluorescence (AF)-based techniques for lymph node evaluation in colorectal and gastric tumors.

METHODS

We studied 30 clinical cases: 15 colorectal cancers and 15 gastric cancers. All of the patients were in the advanced stages of the disease and were candidates for adjuvant therapy. Autofluorescence microspectroscopy and multispectral imaging autofluorescence microscopy have been used to analyze the AF emission of metastatic lymph node sections, excited with 365-nm wavelength radiation. The AF spectra were recorded in the range of 400-700 nm. Monochrome AF images were acquired sequentially through interference filters peaked at 450, 550, and 650 nm, and then combined together in a single red-green-blue image. The AF pattern and the emission spectrum of metastatic lymph nodes have unique characteristics that can be used to distinguish them from the normal ones.

RESULTS

The results, compared with standard histopathologic procedures and with specific staining methods, supplied a satisfactory validation of the proposed technique, revealing the possibility of improving the actual diagnostic procedures for malignant lymph node alterations.

CONCLUSIONS

With the development of appropriate instrumentation, the proposed technique could be particularly suitable in intrasurgical diagnosis of metastatic lymph nodes.

Gastroesophageal carcinoma: individualized surgical therapy

During the twentieth century, surgical management of gastroesophageal carcinoma was developed by an establishment of standard procedures with lymph node dissection according to the metastatic distribution. The "fear" of invisible micrometastasis caused surgeons to perform more aggressive resection with lymphadenectomy to control the disease locally. Although several promising results of extensive lymph node dissection have been reported, the prognostic benefits of extensive surgery have not been proven by prospective randomized trials. A novel technology to detect micrometastasis without extensive surgical resection is required to gastroesophageal carcinoma. The lymphatic mapping technique is one of the attractive candidates for a novel tool to approach this issue.

Location and clinical impact of solitary lymph node metastasis in patients with thoracic esophageal carcinoma

BACKGROUND

The location and clinical impact of solitary lymph node metastasis from thoracic esophageal carcinoma have not been evaluated sufficiently.

METHODS

A consecutive series of 91 patients with a solitary positive lymph node who underwent curative surgery for thoracic esophageal carcinoma was investigated. The prognostic impact was evaluated by univariate analysis and multivariate analysis using Cox's proportional hazards model.

RESULTS

A total of 52 (57%) of the 91 patients showed a solitary positive node beyond the thorax. While 29% of the patients with an upper thoracic tumor showed a cervical node, 13% of the patients with a middle tumor and none of the patients with a lower tumor showed a cervical node. Tumor depth and venous invasion were found to be independent risk factors for poor survival.

CONCLUSIONS

The solitary positive lymph nodes were broadly distributed depending on the tumor location and tumor depth. Tumor depth and venous invasion were risk factors for poor survival in these patients.

Sentinel lymph node in esophageal cancer before neoadjuvant therapy

The technique of sentinel lymph node identification and biopsy has become a new popular technique for surgeon to improve staging of malignant diseases. It may also reduce the risk of complication related to standard lymphadenectomy. The method is still in experimental phase in case of esophageal cancer. A possible complication for employment of the method in this tumor is neoadjuvant therapy. The authors developed the technique for identifying and obtaining the sentinel lymph node in esophageal cancer using minimally invasive surgical technique before neoadjuvant therapy. The sentinel lymph node is detected using 99mTc-labelled nanocolloid. The authors report and discuss possible difficulties of the method in the case of a patient with detected sentinel lymph node in this way.

CONCLUSION

It is possible to identify and obtain a sentinel lymph node before neoadjuvant therapy in esophageal cancer. On the other hand, the clinical significance and applicability of the method of sentinel lymph node still remains controversial in this kind of a tumor.

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.

Sentinel lymph node mapping with technetium-99m colloidal rhenium sulfide in patients with gastric carcinoma

BACKGROUND

The objective of this study was to determine, with the use of technetium-99m colloidal rhenium sulfide, whether the concept of sentinel lymph nodes (SLNs) is applicable to gastric cancers.

METHODS

Fifty-nine gastric cancer patients underwent radical gastrectomy and SLN mapping with an intraoperative hand-held gamma probe. After surgery, each transected lymph node was measured for radioisotope (RI) activities by a well-type scintillation counter.

RESULTS

SLNs were detectable in 57 (96%) of 59 patients. The sensitivity, specificity, and diagnostic accuracy were calculated to be 83.3%, 100%, and 92.9%, respectively. Sensitivity was 100% in the T1 group, 91.6% in the T2 group, and 62.5% in the T3 group. When RI activities were measured with a well-type scintillation counter, every metastatic non-SLN was found to be situated in the same lymphatic basin as the SLNs.

CONCLUSION

The SLN concept is applicable to patients with early gastric cancer (T1). SLN mapping is suitable for identifying the lymphatic basin in cases of gastric cancer.

CT lymphography-navigated sentinel lymph node biopsy in patients with superficial esophageal cancer

BACKGROUND

To evaluate experimentally and clinically the feasibility of a newly developed technique of endoscopic computed tomography (CT) lymphography with endoscopic submucosal injection of iopamidol for esophageal sentinel lymph node (SLN) mapping and biopsy examination.

METHODS

Nine anesthetized dogs underwent CT after endoscopic submucosal injection of 2 mL iopamidol; 1.25-mm thick CT images were obtained before and at 1, 3, 5, 7, and 10 minutes after contrast injection. Clinically, 12 patients with superficial esophageal cancer (preoperative imaging stage: cT1, cN0) underwent CT lymphography in a similar fashion at 1, 5, and 10 minutes after peritumoral injection, followed by radical esophagectomy and regional lymph node dissection under CT lymphography guidance.

RESULTS

CT lymphography visualized the draining lymphatic vessels and SLNs within 5 minutes after contrast injection. All 14 SLNs in dogs (average, 1.5 nodes per animal; range, 1-2) and 28 SLNs in patients (average, 2.3 nodes per patient; range, 1-4) were found intraoperatively at the correct location under CT lymphography guidance. Lymph node metastasis could be detected with excellent sensitivity and accuracy in this small number of patients with no false-negative findings; metastasis was positive only in the preoperatively identified SLNs in 4 patients and in both SLNs and distant nodes in 1 patient, and was negative in all resected nodes in the remaining 7 patients.

CONCLUSIONS

Endoscopic CT lymphography appears to allow accurate identification of direction and locations of lymph flow and SLNs, and has the potential clinical applicability for esophageal SLN mapping and biopsy examination, but will require a large study to determine its accuracy and usefulness.

Surgical strategies for early esophageal adenocarcinoma

The need for extensive surgical resection for early-stage esophageal adenocarcinoma has been challenged by the increasing frequency of early detection in patients with Barrett's esophagus undergoing surveillance endoscopy. Limited endoscopic or surgical procedures are promoted as alternatives to radical esophagectomy and lymphadenectomy in such patients. Currently available data show that limited surgical resection of the distal esophagus with regional lymphadenectomy and interposition of an isoperistaltic jejunal segment is a safe and oncologically adequate procedure in this situation and provides good quality of life. This is in contrast to endoscopic ablation or endoscopic mucosal resection, which are associated with high tumour recurrence rates and persistence of premalignant Barrett esophagus. New technologies for accurate prediction of the presence and pattern of lymphatic spread-e.g. sentinel node techniques and artificial neural networks-may allow a further reduction of the invasiveness of surgical resection without compromising cure rates.

Early esophageal cancer: pattern of lymphatic spread and prognostic factors for long-term survival after surgical resection

OBJECTIVE

The objective of this study was to assess the prevalence and pattern of lymphatic spread in patients with early squamous cell and adenocarcinoma and identify prognostic factors for long-term survival after resection and lymphadenectomy.

SUMMARY BACKGROUND DATA

Limited endoscopic approaches without lymphadenectomy are increasingly applied in patients with early esophageal cancer.

MATERIAL AND METHODS

A total of 290 patients with early esophageal cancer (157 adenocarcinoma, 133 squamous cell cancer) had surgical resection with systematic lymphadenectomy. Specimens were assessed for prevalence and pattern of lymphatic spread. Prognostic factors were determined by multivariate analysis.

RESULTS

None of the 70 patients with adenocarcinoma limited to themucosa had lymphatic spread, as compared with 2 of 26 with mucosal squamous cell cancer. Lymphatic spread was more common in patients with submucosal squamous cell cancer as compared with submucosal adenocarcinoma (36.4% versus 20.7%). Although lymph node metastases were usually limited to locoregional lymph node stations in early adenocarcinoma, distant lymphatic spread was frequent in early squamous cell cancer. On multivariate analysis, only histologic tumor type and the presence of lymph node metastases were independent predictors of long-term survival. Five-year survival rate was 83.4% for early adenocarcinoma versus 62.9% for early squamous cell cancer and 48.2% versus 79.5% for patients with/without lymphatic spread.

DISCUSSION

Prevalence and pattern of lymphatic spread as well as long-term prognosis differ markedly between early esophageal squamous cell and adenocarcinoma. Limited resection techniques and individualized lymphadenectomy strategies appear applicable in patients with early adenocarcinoma.

Early esophageal cancer: pattern of lymphatic spread and prognostic factors for long-term survival after surgical resection

OBJECTIVE

The objective of this study was to assess the prevalence and pattern of lymphatic spread in patients with early squamous cell and adenocarcinoma and identify prognostic factors for long-term survival after resection and lymphadenectomy.

SUMMARY BACKGROUND DATA

Limited endoscopic approaches without lymphadenectomy are increasingly applied in patients with early esophageal cancer.

MATERIAL AND METHODS

A total of 290 patients with early esophageal cancer (157 adenocarcinoma, 133 squamous cell cancer) had surgical resection with systematic lymphadenectomy. Specimens were assessed for prevalence and pattern of lymphatic spread. Prognostic factors were determined by multivariate analysis.

RESULTS

None of the 70 patients with adenocarcinoma limited to themucosa had lymphatic spread, as compared with 2 of 26 with mucosal squamous cell cancer. Lymphatic spread was more common in patients with submucosal squamous cell cancer as compared with submucosal adenocarcinoma (36.4% versus 20.7%). Although lymph node metastases were usually limited to locoregional lymph node stations in early adenocarcinoma, distant lymphatic spread was frequent in early squamous cell cancer. On multivariate analysis, only histologic tumor type and the presence of lymph node metastases were independent predictors of long-term survival. Five-year survival rate was 83.4% for early adenocarcinoma versus 62.9% for early squamous cell cancer and 48.2% versus 79.5% for patients with/without lymphatic spread.

DISCUSSION

Prevalence and pattern of lymphatic spread as well as long-term prognosis differ markedly between early esophageal squamous cell and adenocarcinoma. Limited resection techniques and individualized lymphadenectomy strategies appear applicable in patients with early adenocarcinoma.

Current staging of esophageal carcinoma

The rational treatment of esophageal cancer requires the complete evaluation and preoperative staging of this disease. As the incidence of esophageal cancer increases, more clinicians will face the difficult task of allocating the appropriate treatment course for these patients. Accurate esophageal cancer staging is critical if stage-dependent algorithms are used to direct appropriate therapies. Although all of the staging techniques discussed may potentially provide useful information, it is not possible to use all techniques in all patients, especially given the limited availability of resources. The optimal staging strategy has not yet been determined; the authors provide the general algorithm used in our institution. Ultimately,minimally invasive surgical approaches will allow surgeons to evaluate locoregional disease with little or no procedure-associated morbidity, much as mediastinoscopy is used in lung cancer staging. Although currently the use of molecular biologic techniques may only be investigational, it holds great promise in the future.

Intraoperative identification of esophageal sentinel lymph nodes with near-infrared fluorescence imaging

OBJECTIVE

In esophageal cancer, selective removal of involved lymph nodes could improve survival and limit complications from extended lymphadenectomy. Mapping with vital blue dyes or technetium Tc-99m often fails to identify intrathoracic sentinel lymph nodes. Our purpose was to develop an intraoperative method for identifying sentinel lymph nodes of the esophagus with high-sensitivity near-infrared fluorescence imaging.

METHODS

Six Yorkshire pigs underwent thoracotomy and received submucosal, esophageal injection of quantum dots, a novel near-infrared fluorescent lymph tracer designed for retention in sentinel lymph nodes. Six additional pigs underwent thoracotomy and received submucosal esophageal injection of CW800 conjugated to human serum albumin, another novel lymph tracer designed for uptake into distant lymph nodes. Finally, 6 pigs received submucosal injection of the fluorophore-conjugated albumin with an endoscopic needle through an esophagascope. These lymph tracers fluoresce in the near-infrared, permitting visualization of migration to sentinel lymph nodes with a custom intraoperative imaging system.

RESULTS

Injection of the near-infrared fluorescent lymph tracers into the esophagus revealed communicating lymph nodes within 5 minutes of injection. In all 6 pigs that received quantum dot injection, only a single sentinel lymph node was identified. Among pigs that received fluorophore-conjugated albumin injection, in 5 of 12 a single sentinel lymph node was revealed, but in 7 of 12 two sentinel lymph nodes were identified. There was no dominant pattern in the appearance of the sentinel lymph nodes either cranial or caudal to the injection site.

CONCLUSION

Near-infrared fluorescence imaging of sentinel lymph nodes is a novel and reliable intraoperative technique with the power to assist with identification and resection of esophageal sentinel lymph nodes.

Prediction of gastric cancer lymph node status by sentinel lymph node biopsy and the Maruyama computer model

AIMS

The extent of lymph node dissection in gastric cancer remains controversial. The Maruyama computer model and the sentinel lymph node biopsy (SLNB) are compared for their value to predict the nodal status and lead to stage-adapted surgery.

METHODS

Thirty four patients with stage I-IV gastric cancer underwent both staging procedures. For SLNB, 15 patients underwent endoscopic, peri-tumoural injection of (99m)Tc-colloid, and 19 patients were injected of Patent blue V. All 'hot' or blue sentinel lymph nodes (SLNs) were separately excised and histopathologically assessed. If the SLN was negative after routine staining by H&E, it was processed completely and reanalysed after immunohistochemistry.

RESULTS

At least, one SLN was detected by means of SLNB in 33/34 of the patients. The sensitivity to identify a positive nodal status was 22/33 and the specificity/positive predictive value was 10/10 and 22/22. Additional micrometastases or isolated tumour cells in the SLN led to 'upstaging' of 5/15, initially classified as nodal negative by H&E-staining. Using the Maruyama computer model, a sensitivity of 22/23 for the correct prediction of the lymph node involvement was associated with a specificity of 2/10 and a positive predictive value of 22/30.

CONCLUSIONS

The clinical impact of the Maruyama computer model is limited due to low specificity and a low positive predictive value, rendering the method less useful as an indicator for individualised surgery.

Surgery for early stage esophageal adenocarcinoma

Current treatment recommendations for early esophageal adenocarcinoma range from radical esophagectomy with extensive lymphadenectomy, limited surgical resection with/without regional lymphadenectomy to endoscopic mucosectomy or ablation. A comparison of treatment associated morbidity, tumor recurrence rates, and functional outcome suggests that none of these alternatives can be universally recommended. Rather, an individualized strategy should be employed based on depth of tumor penetration into the mucosa/submucosa, presence of lymph node metastases, multicentricity of tumor growth, length of the underlying Barrett mucosa and comorbidity of the affected patient. Endoscopic mucosectomy may suffice for an isolated focus of high-grade neoplasia or mucosal cancer, provided the neoplasia and underlying Barrett mucosa can be removed completely. Surgical resection is the treatment of choice for tumors invading the submucosa, multicentric tumors and recurrence after endoscopic mucosectomy. The extent of surgical resection must be guided by the length of the Barrett mucosa. In most instances a complete tumor resection and removal of the entire Barrett mucosa can be achieved by a limited transabdominal approach, and therefore subtotal esophagectomy may not be necessary. Application of the sentinel node technology may in the future allow to limit systematic lymphadenectomy to the rather small subgroup of patients who in fact have lymph node metastases.