Lymphatic mapping and focused analysis of sentinel lymph nodes upstage gastrointestinal neoplasms

Use of indocyanine green near-infrared lymphography to detect sentinel lymph nodes in a dog with a malignant insulinoma: a case report

Malignant insulinoma is the most common type of neuroendocrine tumor found in the pancreas of dogs. Canine insulinoma displays malignant behavior with a high rate of metastasis. The most common sites of metastases are the draining lymph nodes, which are also the primary location sites for the recurrence of functional disease. However, identifying metastatic nodes can often be complicated, as the pancreas is drained by numerous lymphatic centers, and clinical enlargement or structural changes may not always be present in metastatic nodes. Additionally, unaltered nodes are frequently small (a few millimeters) and can be hard to distinguish from the surrounding tissues. Therefore, lymphadenectomy is generally recommended for affected dogs. Unlike in human medicine, there are currently no established strategies for lymph node resection in dogs with malignant insulinoma. This report presents a technique for identifying and removing sentinel nodes using indocyanine green and near-infrared lymphography (NIRFL) during surgery. A total of six sentinel nodes were detected and resected with this method. This technique could provide a more structured approach for lymph node resection in affected dogs and potentially in humans in the future. However, its therapeutic benefits must be evaluated in a larger cohort of cases.

Mapping the Mesentery Using ICG

Indocyanine green (ICG) fluorescent imaging has been used in colorectal surgery to assess intraoperative blood flow to the colon. However, its use has expanded to allow imaging of the lymphatic drainage within the mesentery in cancer resections. This technique can been used for real-time visualization of lymph nodes, and the detection of sentinel lymph nodes, lateral sidewall nodes, metastatic lymph nodes, and peritoneal metastases. Ultimately, this provides a more informative map of the mesentery displaying lymphatics and blood flow. The technique is economical and easy to use by the surgeon intraoperatively. ICG lymphangiography has the potential to aid the surgeon to ensure complete lymphadenectomy is performed in cancer resections.

Application of Magnetic Nanoparticles for Rapid Detection and In Situ Diagnosis in Clinical Oncology

Screening, monitoring, and diagnosis are critical in oncology treatment. However, there are limitations with the current clinical methods, notably the time, cost, and special facilities required for radioisotope-based methods. An alternative approach, which uses magnetic beads, offers faster analyses with safer materials over a wide range of oncological applications. Magnetic beads have been used to detect extracellular vesicles (EVs) in the serum of pancreatic cancer patients with statistically different EV levels in preoperative, postoperative, and negative control samples. By incorporating fluorescence, magnetic beads have been used to quantitatively measure prostate-specific antigen (PSA), a prostate cancer biomarker, which is sensitive enough even at levels found in healthy patients. Immunostaining has also been incorporated with magnetic beads and compared with conventional immunohistochemical methods to detect lesions; the results suggest that immunostained magnetic beads could be used for pathological diagnosis during surgery. Furthermore, magnetic nanoparticles, such as superparamagnetic iron oxide nanoparticles (SPIONs), can detect sentinel lymph nodes in breast cancer in a clinical setting, as well as those in gallbladder cancer in animal models, in a surgery-applicable timeframe. Ultimately, recent research into the applications of magnetic beads in oncology suggests that the screening, monitoring, and diagnosis of cancers could be improved and made more accessible through the adoption of this technology.

Intraoperative laparoscopic detection of sentinel lymph nodes with indocyanine green and superparamagnetic iron oxide in a swine gallbladder cancer model

Mapping of sentinel lymph nodes (SLNs) can enable less invasive surgery. However, mapping is challenging for cancers of difficult-to-access visceral organs, such as the gallbladder, because the standard method using radioisotopes (RIs) requires preoperative tracer injection. Indocyanine green (ICG) and superparamagnetic iron oxide (SPIO) have also been used as alternative tracers. In this study, we modified a previously reported magnetic probe for laparoscopic use and evaluated the feasibility of detecting SLNs of the gallbladder using a laparoscopic dual tracer method by injecting ICG and SPIO into five swine and one cancer-bearing swine. The laparoscopic probe identified SPIO nanoparticles in the nodes of 4/5 swine in situ, the magnetic field counts were 2.5-15.9 μT, and fluorescence was detected in SLNs in all five swine. ICG showed a visual lymph flow map, and SPIO more accurately identified each SLN with a measurable magnetic field quite similar to the RI. We then developed an advanced gallbladder cancer model with lymph node metastasis using recombination activating gene 2-knockout swine. We identified an SLN in the laparoscopic investigation, and the magnetic field count was 3.5 μT. The SLN was histologically determined to be one of the two metastatic lymph nodes. In conclusion, detecting the SLNs of gallbladder cancer in situ using a dual tracer laparoscopic technique with ICG and SPIO was feasible in a swine model.

The accuracy of sentinel node biopsy by 99mTc-sodium phytate in patients with pancreatic cancer

Backgrounds/Aims

Pancreaticoduodenectomy is the only potentially curative treatment for pancreatic cancer. The identification of the first nodal drainage site (sentinel node) may improve the detection of metastatic nodes and can contribute to a less invasive surgery. We aimed to determine the accuracy of sentinel node mapping in patients with pancreatic cancer using intraoperative radiotracer injection technique.

Methods

At surgical exposure, peritumoral injection of 0.4-0.5 mci/0.5 ml of 99mTc- sodium phytate was performed. After tumor resection, sentinel nodes were investigated in the most common areas using a hand-held gamma probe. Any lymph node with in vivo count twice the background was considered as sentinel node, thus, it was removed and sent for pathological assessment. Then a standard lymph node dissection was performed for all patients.

Results

Fourteen patients with cancer in the head of the pancreas were included in this study. Overall, 180 lymph nodes were harvested with a mean of 11.6±4.7 lymph nodes per patient. In eight patients, at least one sentinel node could be identified (detection rate about 64%). False negative rate of the study was 3/5 (60%).

Conclusions

Our study revealed insufficient diagnostic accuracy and high false negative rate for sentinel lymph node mapping with 99mTc- sodium phytate in pancreatic cancer.

S122: impact of fluorescence and 3D images to completeness of lateral pelvic node dissection

BACKGROUND

Lateral pelvic lymph node dissection (LPND) is a technically demanding procedure. Consequently, there is a possibility of incomplete dissection of lateral pelvic lymph nodes (LPNs). We aimed to identify metastatic LPNs intraoperatively in real-time under dual guidance of fluorescence imaging and 3D lymphovascular reconstruction, and then to remove them completely.

METHODS

Rectal cancer patients who were scheduled to undergo LPND after preoperative chemoradiotherapy (CRT) were prospectively enrolled. We traced changes in suspected metastatic LPNs during preoperative CRT and defined them as index LPNs on post-CRT imaging studies. For fluorescence imaging, indocyanine green (ICG) at a dose of 2.5 mg was injected transanally around the tumor before the operation. For 3D reconstruction images, each patient underwent preoperative axial CT scan with contrast (0.6 mm slice thickness). These images were then manipulated with OsiriX. Index LPNs and essential structures in the pelvic sidewall, such as the obturator nerve, were reconstructed with abdominal arteries from 3D volume rendering. All surgical procedures were performed via laparoscopic or robotic approach.

RESULTS

From March to July 2017, ten rectal cancer patients underwent total mesorectal excision with LPND after preoperative CRT under dual image guidance. Bilateral LPND was performed in five patients. All index LPNs among ICG-bearing lymph nodes were clearly identified intraoperatively by matching with their corresponding 3D images. Pathologic LPN metastasis was confirmed in four patients (40.0%) and in five of the 15 dissected pelvic sidewalls (33.0%). All metastatic LPNs were identified among index LPNs. Four (80.0%) of the five metastatic LPNs were located in the internal iliac area.

CONCLUSION

Index LPNs among ICG-bearing lymph nodes in pelvic sidewall were clearly identified and completely removed by matching with their corresponding 3D reconstruction images. Further studies and long-term oncologic outcomes are required to determine the real impact of dual image guidance in LPND.

Detection of melanoma metastases with the sentinel node biopsy: the legacy of Donald L. Morton, MD (1934-2014)

Dr. Donald L. Morton was clearly the pioneer of the sentinel node biopsy, which was a major advance in oncology that has improved the management of cancer patients worldwide. He conducted a series of practice-changing clinical trials to validate the important staging role of the sentinel lymph node biopsy for melanoma, and also spawned other studies that demonstrated its staging value in multiple other cancer types, most notably in breast cancer, gastric cancer, and colorectal cancer. His many contributions in this field have provided a unique opportunity to study host/tumor relationships, since the sentinel lymph node is the first location were the host immune defenses are confronted with metastasis arising from the primary cancer.

Intraoperative Radiochromoguided Mapping of Sentinel Lymph Node in Colon Cancer

Aims and Background

The aim of our study was to assess the feasiblility of sentinel lymph node (SLN) detection in colon cancer using a radiochromoguided technique. The regional lymph node status is crucial for colorectal cancer staging and the stage of disease at the time of diagnosis is the main factor influencing therapeutic decision-making and patient survival.

Methods and Study Design

Between April and June 2001 eight patients with colon cancer were studied by radiochromoguided sentinel lymph node mapping. At the time of surgery 2 ml of patent blue dye was injected around the tumor, followed after 10 minutes by 2 ml of 99mTc-labeled albumin. After 30 minutes the SLN was identified by a gamma probe. Surgery was completed by standard resection. The SLN was processed for permanent hematoxylin and eosin staining and for immunohistochemical examination with anti-CEA and anti-cytokeratin antibodies.

Results

SLNs were identified in six patients; two were negative for metastasis by hematoxylin-eosin and immunohistochemical examination, two were positive for metastasis by both methods, and two were negative for metastasis by hematoxylin-eosin but positive by immunohistochemical examination. There were no false negative SLNs and no complications occurred.

Conclusion

The actual utility of SLN detection for prognostic purposes is still unknown, but intraoperative radiochromoguided SLN mapping is technically feasible in colon cancer, although it is associated with more technical difficulties than in breast cancer and malignant melanoma.

Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision: A Systematic Review

BACKGROUND

Extended mesocolic lymph node dissection in colon cancer surgery seems to improve oncological outcome. A possible reason might be related to metastases in the central mesocolic lymph nodes.

OBJECTIVE

The purpose of this study was to describe the pattern of mesocolic lymph node metastases, particularly in central lymph nodes, and the risk of skip, aberrant, and gastrocolic ligament metastases as the argument for performing extended lymph node dissection.

DATA SOURCES

EMBASE and PubMed were searched using the terms colon or colorectal with sentinel node, lymph node mapping, or skip node; lymph node resection colon; and complete or total and mesocolic excision.

STUDY SELECTION

Studies describing the risk of metastases in central, skip, aberrant, and gastrocolic ligament lymph node metastases from colon adenocarcinomas in 10 or more patients were included. No languages were excluded.

MAIN OUTCOME MEASURES

The risk of metastases in the central mesocolic lymph nodes was measured.

RESULTS

A total of 2052 articles were screened, of which 277 underwent full-text review. The 47 studies fulfilling the inclusion criteria were very heterogeneous, and meta-analyses were not considered appropriate. The risk of central mesocolic lymph node metastases for right-sided cancers varies between 1% and 22%. In sigmoid cancer, the risk is reported in ≤12% of the patients and is associated with advanced T stage.

LIMITATIONS

The retrospective design and heterogeneity, in terms of definitions of lymph node location, tumor sites, stage, morphology, pathology assessment, and inclusion criteria (selection bias), of the included studies were limitations. Also, anatomic definitions were not uniform.

CONCLUSIONS

The present literature cannot give a theoretical explanation of a better oncological outcome after extended lymph node dissection. Consensus for a standardization of anatomical definitions and surgical and pathological assessments is warranted for future mapping studies.

Sentinel lymph node biopsy and nodal ultrastaging in colorectal cancer

The tumor status of the regional lymph nodes is the most important prognostic indicator in colorectal cancer (CRC), as it is in other solid tumors. Sentinel lymph node biopsy (SLNB), which has profoundly impacted the treatment of melanoma and breast cancer, has been applied in CRC in an attempt to improve nodal staging accuracy. The challenge lies in identifying patients who have tumor-negative nodes but are at high risk of regional or distant failure and therefore may benefit from adjuvant chemotherapy. Because standard pathological analysis of lymph nodes may incorrectly stage colon cancer, multiple studies have investigated nodal ultrastaging based on identification and immunohistochemical and/or molecular assessment of the sentinel node. This review focuses on the technique of SNLB, its feasibility and validity, and the controversies that remain regarding the clinical significance of nodal ultrastaging in CRC.

Aberrant drainage of sentinel lymph nodes in colon cancer and its impact on staging and extent of operation

BACKGROUND

The role of aberrant lymphatic drainage in changing operations for patients undergoing sentinel lymph node mapping in colon cancer has not been described on a large scale.

METHODS

Patients with colon cancer underwent sentinel lymph node mapping and standard oncologic resection. Aberrant lymphatic drainage was identified outside the standard resection margin, requiring change of the extent of operation. Objectives were to identify the frequency of aberrant lymphatic drainage leading to changes of operation and staging.

RESULTS

Among 192 patients undergoing standard oncologic resection, 42 (22%) had extended surgery because of aberrant lymphatic drainage. Nodal positivity was higher in patients undergoing change of operation, at 62% compared with 43% of those undergoing only standard oncologic resection. In 19 of 192 patients (10%), positive sentinel nodes were found in aberrant locations.

CONCLUSIONS

Sentinel node mapping in patients with colon cancer detects aberrant drainage in 22% of patients, changing the extent of operation.

What is the optimal means of staging colon cancer?

Although staging for colon cancer has become more complex over time, it is not clear that this complexity has improved prognostic assessment. Even with revisions in the 7th edition of the AJCC staging system, a clear rank order of prognosis from substage to substage has not been established. Improved staging models will need to be developed, and attempts at further identifying those high-risk patients within each stage may be clinically useful. Through improved quality measures with lymph node yield, advances in colon cancer staging accuracy have been made over the last decade. Determining how to incorporate ultrastaging and molecular techniques will be the challenge for future staging models.

Sentinel lymph node mapping in colon cancer using radiocolloid as a single tracer: a feasibility study

OBJECTIVE

Evaluation of the feasibility and safety of radiocolloid as a tracer for sentinel lymph node (SLN) mapping in colon cancer.

METHODS

A feasibility study was conducted in consecutive colon cancer patients who were surgically treated at our institute. During preoperative colonoscopy, radiocolloid was injected around the tumour, followed by scintigraphic imaging to identify SLNs. SLNs were identified intraoperatively by a gamma probe and postoperatively by additional ex-vivo scintigraphy of the resection specimen. All retrieved SLNs were examined by histopathological ultrastaging. Standard oncologic laparoscopic resections with lymphadenectomy were performed following the identification of SLNs in all patients.

RESULTS

Fourteen patients were included. At least one SLN was identified in 86% of patients. In one patient (7%) SLNs could be detected intraoperatively. In 83% of patients, the SLNs accurately reflected the tumour status of the remaining lymph nodes. Aberrant lymphatic drainage was preoperatively identified in one patient (7%), but this could not be confirmed intraoperatively. Sensitivity was 67% and the false-negative rate was 33%. Seventeen per cent of patients were upstaged because of SLN micrometastases.

CONCLUSION

SLN mapping in colon cancer using radiocolloid as a single tracer is feasible and safe. However, it was difficult to identify SLNs intraoperatively because of high radioactivity at the injection site. Furthermore, the protocol is labour intensive, especially because of the additional colonoscopic tracer injection. Sensitivity is not better than when blue dye is used, and aberrant lymphatic drainage patterns are scarce. Therefore, this technique is not preferred for SLN mapping in colon cancer.

Sentinel lymph node mapping in tumors of the pancreatic body: preliminary report

Aim of the study

Actual lymphatic drainage of pancreatic body neoplasms and the proper extent of lymphadenectomy remain unknown. The aim of the study was to define the exact lymphatic draining pattern using the dye mapping method.

Material and methods

The study enrolled patients who were operated on for tumor of the pancreatic body in the Department of General and Transplant Surgery of the Medical University of Lodz during 2010, with injection of 1 ml of blue dye (Patent Blue, Guerbet) in the centre of the neoplasm and sentinel node identification. Radical surgical management included distal pancreatectomy, whereas gastrojejunal or triple bypass anastomoses were performed in irresectable cases.

Results

The study group consisted of 13 patients with locally advanced tumors of the pancreatic body (T3 and T4, mean tumor size 4.9 cm). Lymphatic mapping was able to identify sentinel nodes in 5 of 13 cases (38.46%). A sentinel node was found in station 11p (3 cases) and 9 (1 case). Skip metastasis to the left gastric artery node (group 7) was noted. All identified sentinel nodes were metastatic; tumor deposits were confirmed in non-sentinel nodes as well.

Conclusions

In advanced pancreatic body tumors feasibility of sentinel node navigation is considerably restricted. Further studies in smaller tumors using optimized newer markers may define the exact lymphatic draining pattern.

Evaluation of lymph node numbers for adequate staging of Stage II and III colon cancer

BACKGROUND

Although evaluation of at least 12 lymph nodes (LNs) is recommended as the minimum number of nodes required for accurate staging of colon cancer patients, there is disagreement on what constitutes an adequate identification of such LNs.

METHODS

To evaluate the minimum number of LNs for adequate staging of Stage II and III colon cancer, 490 patients were categorized into groups based on 1-6, 7-11, 12-19, and ≥ 20 LNs collected.

RESULTS

For patients with Stage II or III disease, examination of 12 LNs was not significantly associated with recurrence or mortality. For Stage II (HR = 0.33; 95% CI, 0.12-0.91), but not for Stage III patients (HR = 1.59; 95% CI, 0.54-4.64), examination of ≥20 LNs was associated with a reduced risk of recurrence within 2 years. However, examination of ≥20 LNs had a 55% (Stage II, HR = 0.45; 95% CI, 0.23-0.87) and a 31% (Stage III, HR = 0.69; 95% CI, 0.38-1.26) decreased risk of mortality, respectively. For each six additional LNs examined from Stage III patients, there was a 19% increased probability of finding a positive LN (parameter estimate = 0.18510, p < 0.0001). For Stage II and III colon cancers, there was improved survival and a decreased risk of recurrence with an increased number of LNs examined, regardless of the cutoff-points. Examination of ≥7 or ≥12 LNs had similar outcomes, but there were significant outcome benefits at the ≥20 cutoff-point only for Stage II patients. For Stage III patients, examination of 6 additional LNs detected one additional positive LN.

CONCLUSIONS

Thus, the 12 LN cut-off point cannot be supported as requisite in determining adequate staging of colon cancer based on current data. However, a minimum of 6 LNs should be examined for adequate staging of Stage II and III colon cancer patients.

The Feasibility of an Ex-vivo Sentinel Lymph Mapping Using Preoperative Radioisotope Injection in Cases of Extraperitoneal Rectal Cancer

PURPOSE

The purpose of this research was to evaluate the feasibility of sentinel lymph node (SLN) mapping involving transanal injection with an ex-vivo mapping in patients with rectal cancer.

METHODS

Between April 2007 and December 2009, 20 consecutive patients with T1-3, N0-1 clinical stage rectal cancer preoperatively underwent a SLN procedure using submucosal (99m)Tc-phytate injection. All the patients underwent a total mesorectal excision. After the standard surgical resection, all specimens were identified on lymphoscintigraphy, and bench work was done to pick up the sentinel node basin. All the lymph nodes (non-SLNs and SLNs) were examined using conventional hematoxylin and eosin staining and immunohistochemistry with anti-cytokeratin antibodies.

RESULTS

SLNs were identified from 19 of 20 patients with rectal cancer. The total number of sentinel nodes retrieved from the surgical specimens was 29, and the mean number per patient was 1.6 (range, 0 to 4). In three patients, the SLN was the only positive lymph node. There was one false-negative case with a sensitivity of 88.8% and two upstaged cases (20.0%). The SLN samples from rectal cancer are mainly localized in the pararectal region, but aberrant nodes receive direct drainage from the rectal cancer. On planar lymphoscintigraphy, 15.7% of all patients had aberrant lymphatic drainage to the sigmoid mesenteric or sigmoid lymph node station.

CONCLUSION

In conclusion, the intraoperative transanal injection for ex-vivo SLN navigation is a safe, feasible surgical modality in patients with rectal cancer. Large studies are warranted to determine the clinical significance of the SLN concept and micrometastasis in rectal cancer.

R0 resection in the treatment of gastric cancer: Room for improvement

Gastric carcinoma is one of the most frequent malignancies in the world and its clinical behavior especially depends on the metastatic potential of the tumor. In particular, lymphatic metastasis is one of the main predictors of tumor recurrence and survival, and current pathological staging systems reflect the concept that lymphatic spread is the most relevant prognostic factor in patients undergoing curative resection. This is compounded by the observation that two-thirds of gastric cancer in the Western world presents at an advanced stage, with lymph node metastasis at diagnosis. All current therapeutic efforts in gastric cancer are directed toward individualization of therapeutic protocols, tailoring the extent of resection and the administration of preoperative and postoperative treatment. The goals of all these strategies are to improve prognosis towards the achievement of a curative resection (R0 resection) with minimal morbidity and mortality, and better postoperative quality of life.

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M. Pocard, J.-C. Sabourin In theory, the concept of sentinel lymph node (SLN) biopsy can be applied to cancer surgery for all solid cancers. Yet sentinel lymph node biopsy has not become a standard part of gastrointestinal cancer surgery. It has been of value in the assessment of small early-stage gastric cancers, but has only achieved widespread practice in Japan. Studies of SLN biopsy in colon cancer have not shown it to be a reliable predictor of N+ status and therefore don't permit the omission of lymph node dissection in selected cases. On the other hand, as a form of intra-operative lymph node mapping, dye injection of the SLN may demonstrate aberrant lymphatic drainage and could occasionally permit the sparing of a middle colic artery whose sacrifice would otherwise be dictated by standard drainage patterns. SLN biopsy may have prognostic usefulness by demonstrating micrometastases; careful serial sectioning focussed on the SLN may detect nests of metastatic cells on HE staining, thereby converting a tumor from Stage I (TxN0M0) to Stage II (TxN1M0). This finding has been noted in 10-15% of cases. However, the prognostic value of micrometastases detected only by immunohistochemical staining or PCR has not been demonstrated. For cancers of the anal canal, SLN biopsy of inguinal nodes has been tested as a means of establishing the indications for inguinal lymph node dissection.

Upstaging benefits and accuracy of sentinel lymph node mapping in colorectal adenocarcinoma nodal staging

BACKGROUND AND OBJECTIVES

Sentinel lymph node (SLN) mapping is an additional method for improving colorectal cancer nodal staging. The purpose of the study was to define the method's accuracy in nodal staging, its upstaging benefits and to identify the predictive factors for its failure.

METHODS

Lymphatic mapping was performed using technetium-99m-phytate and patent blue in 52 consecutive colorectal adenocarcinoma patients. Enhanced pathological examination was carried out on SLNs with hematoxylin-eosin step-sectioning and immunochemistry.

RESULTS

The patients studied had an average tumor size of 6.5 cm; 85% had T3/T4 tumors; and rectal tumors represented 57.7% of the group. Overall SLN mapping accuracy was 79.5%, with sensitivity of 65.2% and 34.8% false negatives. Upstaging with SLN mapping was 23.1%. Colon tumors had an SLN identification rate of 90.9% and rectal tumors had 63.3% (P = 0.023). Multivariate statistical analysis identified lower rectal tumor (P = 0.009), neoadjuvant treatment (P = 0.029) and tumor size (P = 0.036) as independent risk factors for the inability to detect SLNs.

CONCLUSIONS

Upstaging benefits of SLN mapping should be considered in colon and mid- and upper rectal tumors. The method should be avoided in patients with lower rectal tumors, large tumors and having had neoadjuvant therapy.

The biologic significance of micrometastatic disease and sentinel lymph node technology on colorectal cancer

The sentinel lymph node (SLN) technique has practical applications in multiple solid tumors including colorectal carcinoma. Identifying the SLN(s) provides better staging of the regional lymphatics beyond standard H&E analysis. This additional information assists in predicting biology and may be useful in guiding adjuvant therapy. We postulate the era of sentinel node has ushered in a new generation of node-negative patients; patients that have an exceptionally favorable outcome when compared to historic controls.

Pesquisa do linfonodo sentinela em câncer gástrico com o corante azul patente

OBJETIVO: Avaliar a factibilidade e os resultados de uma técnica pouco invasiva para a pesquisa do linfonodo sentinela (LFNsn) com o uso do corante vital azul patente. MÉTODO: A pesquisa do LFNsn foi realizada em 12 pacientes portadores de adenocarcinoma gástrico que não apresentavam linfonodos suspeitos de metastases durante o estadiamento clínico pré-operatório. Injetou-se nos quatro quadrantes do tumor, 0,5 ml de corante vital azul patente. Os linfonodos que se coraram de azul foram classificados como LFNsn e foram obtidos após a gastrectomia com linfadenectomia D2. Utilizou-se a coloração HE para avaliação anatomopatológica dos LFNsn, e nos casos com LFNsn negativo para HE, foi realizada imuno-histoquímica com pan-citoqueratinas AE1/AE3. RESULTADOS: Dos 12 pacientes, oito eram mulheres, com média de idade de 64,5 (48-87) anos. Identificaram-se em média 3,25 (2-6) LFNsn por paciente. A factibilidade da técnica foi de 100%. A acurácia do método foi de 91,6% . Em 11 de 12 casos foi possível predizer as características linfonodais regionais pela concordância da análise anatomopatológica entre os LFNsn e não sentinelas(LFNñsn). CONCLUSÃO: A pesquisa do linfonodo sentinela em câncer gástrico é factível com o uso da técnica do corante azul patente. O método mostrou ser promissor como técnica minimamente invasiva para estadiar tumores gástricos, nesta casuística inicial.

Distribution of solitary lymph nodes in primary gastric cancer: A retrospective study and clinical implications

AIM: To investigate the distribution pathway of metastatic lymph nodes in gastric carcinoma as a foundation for rational lymphadenectomy.

METHODS: We investigated 173 cases with solitary or single station metastatic lymph nodes (LN) from among 2476 gastric carcinoma patients. The location of metastatic LN, histological type and growth patterns were analyzed retrospectively.

RESULTS: Of 88 solitary node metastases cases, 65 were limited to perigastric nodes (N₁), while 23 showed skipping metastasis. Among 8 tumors in the upper third stomach, 3 involved right paracardial LN (station number: No.1), and one in the greater curvature was found in No.1. In the 28 middle third stomach tumors, 10 were found in LN of the lesser curvature (No.3) and 6 in LN of the left gastric artery (No.7); 5 of the 20 cases on the lesser curvature spread to No.7, while 2 of the 8 on the greater curvature metastasized to LN of the spleen hilum (No.10). Of 52 lower third stomach tumors, 13 involved in No.3 and 19 were detected in inferior pyloric LN (No.6); 9 of the 29 cases along the lesser curvature were involved in No.6.

CONCLUSION: Transversal and skipping metastases of sentinel lymph nodes (SLN) are notable, and rational lymphadenectomy should, therefore, be performed.

Sentinel lymph nodes of colorectal carcinoma: reappraisal of 123 cases

AIMS

Results concerning the usefulness of the sentinel lymph node (SLN) in colorectal carcinoma have been discordant. The SLN technique may be used to guide surgical resection (lymph mapping), restrict the lymph node analysis solely to the SLN (accuracy) and upgrade tumor staging when micrometastases are specifically detected in the SLN.

METHODS

The blue dye injection technique was used. Serial sections of the SLNs were analyzed after hematoxylin-eosin (HES) staining.

RESULTS

The SLN technique was tested in 123 patients, successfully in 112/118 (feasibility 95%) (five intraoperative exclusions). On average, twenty lymph nodes (range: 5-74) and two SLNs (range: 1-5) were identified. Lymph mapping was used in 11% of patients to guide surgical resection; the SLN was negative in 14 of 36 N+ patients (39% false-negatives); HES staining enabled detection of micrometastases in 8 of 84 initially N0 patients (10% secondary upgrading to N+).

CONCLUSION

Limiting node analysis to the SLN cannot replace a complete pathology examination of all resected lymph nodes. Careful examination of serial sections of the SLN can however affect therapeutic decision making since staging may be upgraded in up to 10% of initially N0 patients.

Sentinel lymph node mapping in colon cancer: current status

BACKGROUND

The primary role of sentinel lymph node (SLN) mapping in colon cancer is to increase the accuracy of nodal staging by identifying those lymph nodes with the greatest potential for harbouring metastatic disease. Ultrastaging techniques aim to identify the otherwise undetected metastases. Until now, no consensus exists as to the most optimal procedure in patients with colon cancer.

METHODS

A systematic literature search on the value of different SLN mapping techniques in patients with colon cancer was performed using the electronic search engine PubMed. Prospective studies published before 1 December 2005 were included and further articles were selected by cross-referencing. The results of different techniques using either blue dye or radiocolloid, were investigated.

RESULTS

The literature search yielded 17 relevant articles. SLN mapping using blue dye was described in 15 studies. Two studies reported the results of SLN mapping using a combination of blue dye and radiocolloid. The reported results on identification rate varied between 71 and 100%. Accuracy rates were between 78 and 100%, sensitivity rates between 25 and 100% and true upstaging rates between 0 and 26%. The results were not affected by the addition of radiocolloid to blue dye.

CONCLUSIONS

Sentinel lymph node mapping in patients with colon cancer remains an experimental procedure with varying results. Further evaluation may lead to a standardized technique that offers the potential for significant upstaging of stage II patients. This may have important implications as to tailor adjuvant chemotherapeutic regimens in these patients.

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.

Oncologic results of laparoscopic D3 lymphadenectomy for male sigmoid and upper rectal cancer with clinically positive lymph nodes

BACKGROUND

Many Japanese surgeons routinely perform extended D3 lymph node dissection for the treatment of advanced rectosigmoid cancer with a view to achieving better tumor control. However, the application of a laparoscopic approach to perform D3 lymphadenectomy has been challenging. This phase 2 prospective study aimed to explore the oncologic results of this surgical approach.

METHODS

The study was conducted during a 6-year period, in consideration of median follow-up time being >3 years. The study subjects were tumor, node, metastasis system stage III rectosigmoid cancer staged by clinical images. The extent of D3 dissection and the postoperative lymph node mapping were according to the guidelines of the Japanese Society for Cancer of the Colon and Rectum. Patients were stratified according to the histopathologically proved highest level of involved lymph nodes and placed into N0, N1, N2, and N3 groups. The primary end points of the study were the estimated time to recurrence and 5-year recurrence rate of cancer after laparoscopic D3 dissection.

RESULTS

The estimated 5-year recurrence rate (20% in the N0 group [n = 10]; 25% in N1 [n = 44]; 33.3% in N2 [n = 30]; and 42.8% in N3 [n = 14]), time to recurrence (mean [95% confidence interval] 59.8 [42.6-76.9] months in the N0 group; 56.8 [48.3-65.2] months in N1; 46.8 [37.5-56.1] months in N2; and 43.9 [28.3-59.4] months in N3), and recurrence patterns were without significant difference (all P values >.05) among N0, N1, N2, and N3 groups. Therefore, by laparoscopic wide anatomic dissection, patients with lymph node involvement could be treated as well as those without lymph node metastasis. Laparoscopic D3 dissection facilitated the collection of more lymph nodes (mean +/- standard deviation, 27.4 +/- 4.2) for histopathologic examination. Mapping of dissected lymph nodes showed that 18.2% (16 of 88) patients had skip lymph node metastasis. D3 dissection facilitated upstaging of cancer (from N0 to N3) in five patients (5.1%). However, this procedure resulted in transient voiding dysfunction in 77.5% patients and loss of ejaculatory function in 91.7%. By laparoscopic approach, the D3 lymph node dissection was safely performed through small wounds, resulting in quick functional recovery and only moderate blood loss (324.8 +/- 44.5 mL), but at the expense of a long operation time (294.4 +/- 34.8 minutes).

CONCLUSIONS

The good short-term oncologic results and quick convalescence mean that the laparoscopic D3 dissection may be recommended for patients with stage III rectosigmoid cancer who could accept the genitourinary dysfunction.

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.

Sentinel node staging in colon carcinoma: value of sentinel lymph node biopsy with radiocolloid and blue staining

BACKGROUND

Nodal staging accuracy is important in the prognosis and selection of patients for chemotherapy. This prospective study aims to assess the feasibility and accuracy of the sentinel lymph node procedure (SNP) using radiocolloid and blue dye in colon carcinoma.

METHODS

In 56 patients, lymphatic mapping was accomplished by means of intraoperatively injecting patent blue and nanocoll subserosally around the tumour. Sentinel nodes (SNs) were harvested ex-vivo. Nodes were stained with H&E. If lymph nodes were interpreted as negative for metastatic tumour, serial sectioning and immunohistochemical staining were performed.

RESULTS

At least one SN was detected in 49 of 53 patients (92.5%). Three patients were excluded because of preoperatively detected metastases. Overall, 121 SN were harvested with a mean of 2.2 SN/patients. Eighteen patients had tumour positive nodes. In four patients, pathological nodes were palpable during operation and were excluded. The SN was histologically negative in 2 of 14 patients with positive nodes (false-negative rate 14.3%). In 5 of 14 patients with positive nodes, the SN was the exclusive site of regional nodal metastasis. Four patients were upstaged by immunohistochemical staining (28.6%). The negative predictive value was 93.9% and the overall accuracy 95.6%. Scintigraphy was done in 17 patients. In three patients the SN was detected only by this modality.

DISCUSSION

The SN biopsy with the combined technique proved a feasible technique with a steep learning curve. It can change the initial staging from stage II to stage III colon carcinoma. Scintigraphy can improve the success rate of the technique.

Detection of micrometastases and skip metastases with ex vivo sentinel node mapping in carcinoma of the colon and rectum

BACKGROUND

The debate over sentinel lymph node mapping (SLNM) and focused pathologic examination to detect micrometastases in patients with colorectal cancer (CRC) continues. We present in this paper our experience with SLNM for CRCs to improve staging. In addition, we have detailed the mapping procedure on an anatomical basis to define skip metastasis.

MATERIALS AND METHODS

Forty-seven patients underwent ex vivo SLNM. Immediately after resection, 1 ml of patent blue VF was injected submucosally around the tumor. Lymph nodes harvested from the first 15 patients were mapped in a standard fashion as the blue-stained nodes (SLNs), and the others (non-SLNs) were dissected away. In the remaining 32 patients, the lymph nodes were also mapped separately in relation to their anatomic location and described as epicolic-paracolic, intermediate, and principal. The blue-stained nodes (SLNs) and non-SLNs, negative by hematoxylin and eosin stain, were further stained with cytokeratin immunohistochemical analysis and carcinoembryonic antigen.

RESULTS

A total of 873 histologically confirmed LNs were examined with a mean of 18.6+/-8.1 nodes per patient. In 46 of 47 patients (97.8%), SLNs were identified. Immunohistochemical staining revealed micrometastases in the lymph nodes of four patients, which were negative by conventional methods. Anatomical skip metastases were noted in 4 of 32 patients studied (12.5%).

CONCLUSION

Ex vivo SLNM in CRCs is a feasible technique with a high SLN identification rate. Results of anatomical mapping of lymph nodes correlates with the limited literature, suggesting that occult skip metastases can occur in the apical lymph node group and may occur outside the resected area.

Pathological Evaluation of Sentinel Lymph Nodes

The sentinel lymph nodes are the most likely site of nodal metastasis. Their focused analysis results in upstaging cancers, although the extra yield from a more intensive work-up is generally dominated by micrometastases and isolated tumor cells. Nodal staging is generally done to reflect systemic spread of solid tumors and guide treatment accordingly. However, in general, the two processes of haematogenous and lymphogenic spread are not causally interrelated, and the extrapolation from low-volume nodal involvement to systemic involvement and therapeutic consequences of this extrapolation are still under investigation.

Re-fixation in a lymph node revealing solution is a powerful method for identifying lymph nodes in colorectal resection specimens

AIM

To verify an impact of a lymph node revealing solution (LRS) on the number of lymph nodes (LN) revealed in colorectal resection specimens.

MATERIAL AND METHOD

Fifty-nine cases of rectosigmoid carcinomas divided into two subgroups-stage pT2&3 (20 cases) and ypT2&3 (with pre-operative radiotherapy-39 cases)-were formalin fixed for 42-72 h, serially sectioned and re-fixed in LRS containing ethanol, diethyl ether, glacial acetic acid, and formalin for 24 h. The number of LNs was matched to a control group consisting of 34 cases of colorectal carcinoma, 14 pT2&3 and 20 ypT2&3 rectosigmoid carcinomas examined routinely. Results were statistically tested by Student's t-test.

RESULTS

In the study group the total number of revealed LNs was 869, range 1-48, average 14.7 per specimen, median 15. In the control group the number of LNs was 200, range 0-13, average 5.9 per specimen, median 6. The difference between the study and the control group was statistically significant (P = 0.05).

CONCLUSION

Using LRS leads to a significant increase in the number of revealed LNs in colorectal resection specimens and makes it possible to find more than 12 LNs in a majority of stage pT2 and pT3 adenocarcinomas.

A multicenter trial of sentinel lymph node mapping in colorectal cancer: prognostic implications for nodal staging and recurrence

BACKGROUND

Sentinel lymph node (SLN) mapping (M) for staging in colorectal cancer (CRCa) remains controversial and needs to be validated. This study analyzes results of SLNM at a multi-institutional level for CRCa.

METHODS

Group A patients underwent SLNM with 1 to 3 mL of 1% lymphazurin. First 1 to 4 blue lymph nodes were designated as SLNs and had focused analysis. Group B had standard resection and nodal staging. Patients with a minimum of 2 years of follow-up were analyzed for recurrence.

RESULTS

Overall nodal metastasis were 50% for 500 group A patients versus 35% for 368 group B patients. In SLNM patients success, accuracy, sensitivity, and negative predictability values were 98%, 96%, 90%, and 93%, respectively. With a 2-year minimum follow-up, 153 group A patients had 7% recurrences compared with 25% in 162 group B patients.

CONCLUSION

SLNM is highly feasible and accurate for staging CRCa with higher detection of nodal metastasis and lower recurrences.

Sentinel node detection after preoperative short-course radiotherapy in rectal carcinoma is not reliable

Background

Seninel node (SN) detection may be used in patients with colonic carcinoma. However, its use in patients with rectal carcinoma may be unreliable. To address this, SN detection was evaluated in patients with rectal carcinoma after short-course preoperative radiotherapy.

Methods

Patent Blue V (1–2 ml) was injected peritumorally and submucosally directly after total mesorectal excision (TME) in 34 patients. The first one to four blue lymph nodes were categorized as SNs. All lymph nodes (non-SNs and SNs) were examined by conventional haematoxylin and eosin stained sections. If the SN was negative for metastasis, additional sections were immunostained with anticytokeratin CK7/8. In addition, SN detection was performed in 57 patients with colonic carcinoma.

Results

A SN was identified in 26 of 34 patients with rectal carcinoma. In three the SN was the only positive lymph node. There were six false-negative SNs (sensitivity 40 per cent) and two patients were upstaged. By contrast, SN detection was possible in 56 of 57 patient with colonic carcinoma with a sensitivity of 90 per cent, and four patients were upstaged.

Conclusion

The SN procedure for rectal carcinoma is not reliable in combination with TME and preoperative short-course radiotherapy.

Ex Vivo Sentinel Lymph Node Study For Rectal Adenocarcinoma: Preliminary Study

Intraoperative sentinel lymph node (SLN) detection has been reported for colon cancer, but no study has focused on rectal cancer. Only an ex vivo technique can be performed easily in this location. We evaluated SLN detection using blue dye injection in patients with rectal adenocarcinoma. This prospective study included 31 patients. Preoperative radiotherapy (45 Gy) was done in 15 cases. After proctectomy the surgical specimen was examined in the operating room. Submucosal peritumoral injections were done. One to three SLNs were retrieved. The SLNs were sectioned at three levels and examined histologically and then, if negative by hematoxylin-eosin (H&E) staining and immunohistochemistry (IHC). There were 7 abdominoperineal resections, 12 colorectal anastomoses, 11 coloanal anastomoses, and 1 Hartmann procedure. The median number of lymph nodes harvested was 21 (7-38). A SLN was identified in 30 cases (feasibility 97%). The mean number of SLNs was 2 (0-3). A micrometastasis was discovered in 3 of 23 pNO cases when H&E was used on multisection levels, thus changing the stage to pN1. Each time the only positive lymph node was the SLN. IHC evaluation did not change the result, as only isolated tumor cells were discovered in one case. Only four of seven N+ patients had a positive SLN, resulting in a false-negative rate of 43%. Ex vivo detection of SLNs is possible for rectal cancer and is a simple technique. Classic analysis using H&E remains the gold standard. However, SLNs detection can change the tumor stage by upstaging nearly 15% of the tumors from T2-3N0 to T2-3 N+.

[Optimization of staging in colon cancer using sentinel lymph node biopsy]

Routine determination of the nodal status in colon cancer is strongly dependent on the individual quality and technique of histopathological assessment and surgical lymph node dissection. We evaluated whether sentinel lymph node biopsy (SLNB) could contribute to an improvement in staging. At least one SLN (median n=2) was detected (detection rate 84%) in each of 38 of 45 patients with primary colon cancer. Ten of these 38 were found to have lymph node metastases by HE staining (26%), six of them in the SLN. Nine of the 28 patients that were initially nodal-negative by HE revealed one micrometastasis and eight cases of isolated tumor cells by immunohistochemical (IHC) staining (32% upstaging response). Including the IHC-positive cases, 19 of the 38 patients were nodal-positive (50%), 15 of them with tumor-infiltrated SLN (overall sensitivity of SLNB 79%). Using the dye method, SLNB is clinically practicable and leads in the majority of the patients to the detection of SLN. The selective, intensified histopathological assessment of SLN identifies small tumor cell deposits in a relevant percentage of patients with little and clinically practicable effort.

Lymphatic staging in colorectal cancer: pathologic, molecular, and sentinel node techniques

PURPOSE

Accurate staging in colorectal cancer is important to predict prognosis and identify patients who could benefit from adjuvant therapy. Patients with lymphatic metastasis, Stage III/Dukes C, are generally treated with adjuvant chemotherapy. Still, patients without lymphatic metastasis do have relapse as high as 27 percent in five years in Dukes B2. It is hypothesized that these patients have occult (micro)metastasis in their lymph nodes. If these (micro)metastasis can be identified, these patients might benefit from adjuvant therapy. We reviewed the literature on procedures to improve lymph node staging.

METHODS

An extensive literature search was performed in PubMed (www.pubmed.com). Using the reference lists, more articles were found.

RESULTS

We found 30 articles about sentinel node in colorectal cancer describing original series. Some groups reported several studies including the same patients. We reported their largest studies. For all other techniques, we only included key articles.

CONCLUSIONS

Many techniques to improve staging have been described. The finding of occult (micro)metastasis is of prognostic significance in most studies. The sentinel node technique has been recently described for use in colorectal cancer. Although it seems clear that this technique has prognostic potential, it is not yet been shown in a follow-up study. Furthermore, the finding of occult (micro)metastasis in any technique used has not been shown to be clinically significant. Whether to treat patients with adjuvant therapy if occult (micro)metastasis are found needs to be proven in future studies.

Sentinel lymph node mapping in colon and rectal cancer: its impact on staging, limitations, and pitfalls

Sentinel lymph node (SLN) mapping has been widely applied in the staging of solid neoplasms including colon and rectal cancer. Since the first reported feasibility study in 1997, there have been numerous publications validating SLN mapping as a highly accurate and powerful upstaging technique for colon and rectal cancer. In addition to refining the technical aspects of this procedure, these studies have investigated the use of other tracers and operative techniques, while determining the indications, limitations, and pitfalls of SLN mapping in patients with colorectal cancers. This chapter reviews the rationale for performing SLN mapping for the accurate staging of colon and rectal cancers, and provides a brief review of the historical background of the development of the procedure. Landmark publications, which have contributed to the current status of the technique, are discussed. We will focus on the technical details of the procedure, and on the pathological evaluation of the specimen and the SLNs. The various tracers and techniques of SLN mapping in colon and rectal cancer will be discussed. We have performed SLN mapping in more than 240 consecutive patients over the past 7 years. The success rates for identifying at least one SLN for colon and rectal cancer were 100% and 90.6%, respectively. The accuracy rates were 95.8% and 100%, respectively. In terms of upstaging, 32.3% of colon cancer patients with nodal metastases and 16.7% of rectal patients with nodal metastases were upstaged by the detection of micrometastases found in the SLNs only. Finally, we will also discuss the current role as well as the future research directions for SLN mapping in colon and rectal cancer.