Sentinel-lymph-node procedure in colon and rectal cancer: a systematic review and meta-analysis. Lancet Oncol. 2011;12:540-550. [PMID: 21549638 DOI: 10.1016/s1470-2045(11)70075-4]

Management of nodal disease from colon cancer in the laparoscopic era

PURPOSE

In colon cancer (CC), nodal involvement is the main prognostic factor following potentially curative (R0) resection. The purpose of this study was to examine data from the literature to provide an up-to-date analysis of the management of nodal disease with special reference to laparoscopic treatment.

METHODS

MEDLINE and EMBASE databases were searched for potentially eligible studies published in English up to July 15, 2014.

RESULTS

In CC, nodal involvement is a frequent event and represents the main risk of cancer recurrence. Node negative patients recur in 10-30 % of cases most likely due to underdiagnosed or undertreated nodal disease. Extended colonic resections (complete mesocolic excision with central vascular ligation; D3 lymphadenectomy) provides a survival benefit and better local control. Sentinel lymph node mapping in addition to standard surgical resection represents an option for improving staging of clinical node negative patients. Both extended resection and sentinel lymph node mapping are feasible in a laparoscopic setting.

CONCLUSIONS

Both extended colonic resection and sentinel lymph node mapping should play a role in the laparoscopic treatment of CC with the purpose of improving control and staging of nodal disease.

Intra-arterial methylene blue injection into ex vivo colorectal cancer specimens improves lymph node staging accuracy: a randomized controlled trial

AIM

A randomized controlled trial was carried out to study the effect of a recently proposed technique of ex vivo intra-arterial methylene blue injection of the surgical specimen removed for colorectal cancer on lymph node harvest and staging.

METHOD

Between May 2012 and February 2013, 100 consecutive colorectal cancer resection specimens in a single institution were randomly assigned to intervention (methylene blue injection) and control (standard manual palpation technique) groups before formalin fixation. The specimen was then examined by the histopathologist for lymph nodes.

RESULTS

Both groups were similar for age, sex, site of tumour, operation and tumour stage. In the intervention group, a higher number of nodes was found [median 23 (5-92) vs. 15 (5-37), P < 0.001], with only one specimen not achieving the recommended minimum standard of 12 nodes [1/50 (2%) vs. 8/50 (16%), P = 0.014]. However, there was no upstaging effect in the intervention group [23/50 (46.0%) vs. 20/50 (40.0%); P = 0.686]. With a significantly lower number of nodes harvested in rectal cancer, the positive effect of the intervention was particularly observed in the patients who underwent preoperative neoadjuvant radiotherapy [median 30 nodes (12-57) vs. 11 (7-15); P = 0.011; proportion of cases with < 12 nodes 0/5 vs. 5/8 (62.5%), P = 0.024].

CONCLUSION

Ex vivo intra-arterial methylene blue injection increases lymph node yield and can help to reduce the number of cases with a lower-than-recommended number of nodes, particularly in patients with rectal cancer having neoadjuvant treatment. The technique is easy to perform, cheap and saves time.

Optimization of sentinel lymph node mapping in bladder cancer using near-infrared fluorescence imaging

BACKGROUND AND OBJECTIVES

Unlike other cancers, the Sentinel Lymph Node (SLN) procedure in bladder cancer requires special attention to the injection technique. The aim of this study was to assess feasibility and to optimize tracer injection technique for SLN mapping in bladder cancer patients using NIR fluorescence imaging.

METHODS

Twenty patients with invasive bladder cancer scheduled for radical cystectomy were prospectively enrolled. Indocyanine green (ICG) bound to human serum albumin (complex ICG:HSA; 500 µM) was injected peritumourally to permit SLN mapping. ICG:HSA was first administrated serosally (n = 5), and subsequently mucosally by cystoscopic injection (n = 15). In the last cohort of 12 patients treated with cystoscopic injection, the bladder was kept filled with saline for at least 15 min.

RESULTS

Fluorescent lymph nodes were observed only in the patient group with cystoscopic injection of ICG:HSA. Filling of the bladder post-injection was of added value to promote drainage of ICG:HSA to the lymph nodes, and in 11 of these 12 patients (92%) one or more NIR fluorescent lymph nodes were identified.

CONCLUSIONS

The current study demonstrates proof-of-principle of using NIR fluorescence imaging for SLN identification in bladder cancer. Cystoscopic injection with distension of the bladder appears optimal for SLN mapping.

Systematic review of methods for individual patient data meta- analysis with binary outcomes

Background

Meta-analyses (MA) based on individual patient data (IPD) are regarded as the gold standard for meta-analyses and are becoming increasingly common, having several advantages over meta-analyses of summary statistics. These analyses are being undertaken in an increasing diversity of settings, often having a binary outcome. In a previous systematic review of articles published between 1999–2001, the statistical approach was seldom reported in sufficient detail, and the outcome was binary in 32% of the studies considered. Here, we explore statistical methods used for IPD-MA of binary outcomes only, a decade later.

Methods

We selected 56 articles, published in 2011 that presented results from an individual patient data meta-analysis. Of these, 26 considered a binary outcome. Here, we review 26 IPD-MA published during 2011 to consider: the goal of the study and reason for conducting an IPD-MA, whether they obtained all the data they sought, the approach used in their analysis, for instance, a two-stage or a one stage model, and the assumption of fixed or random effects. We also investigated how heterogeneity across studies was described and how studies investigated the effects of covariates.

Results

19 of the 26 IPD-MA used a one-stage approach. 9 IPD-MA used a one-stage random treatment-effect logistic regression model, allowing the treatment effect to vary across studies. Twelve IPD-MA presented some form of statistic to measure heterogeneity across studies, though these were usually calculated using two-stage approach. Subgroup analyses were undertaken in all IPD-MA that aimed to estimate a treatment effect or safety of a treatment,. Sixteen meta-analyses obtained 90% or more of the patients sought.

Conclusion

Evidence from this systematic review shows that the use of binary outcomes in assessing the effects of health care problems has increased, with random effects logistic regression the most common method of analysis. Methods are still often not reported in enough detail. Results also show that heterogeneity of treatment effects is discussed in most applications.

What should we intend for minimally invasive treatment of colorectal cancer?

Non-inferiority of laparoscopic treatment of colorectal cancer (CRC) has been demonstrated in randomized controlled trials although operative and perioperative management varies widely among centers. Literature data in English language published up to April 15, 2014 were analyzed in order to give an up to date analysis that would highlights the key aspects of a modern and factual minimally invasive treatment of CRC. Laparoscopic resection is the first choice treatment of colon cancer. Laparoscopic resection of rectal cancer should be considered an investigational procedure to be performed in high volume centers with special interest in laparoscopy and colorectal surgery. Less invasive approaches should be taken into account with the aim of reducing surgical stress. The adoption of ERAS programs has demonstrated to optimize short-term results. Future research should be directed to prove possible long-term advantages, in terms of overall and disease-free survival, of minimally invasive treatment of CRC.

Blue dye injection does not induce dissemination of epithelial cells during SLN procedure in colon cancer patients

INTRODUCTION

The sentinel lymph node (SLN) procedure for colon cancer patients has been increasingly performed over the past decade and has shown advantages regarding lymph node staging. However, there are concerns that the manipulation of the colon, particularly the blue dye injection, results in isolated tumor cell dissemination to lymph nodes. Therefore, the objective of the present study was to evaluate whether the blue dye injection during the SLN procedure for colon cancer induces epithelial cell dissemination to the regional lymph nodes using a fake SLN procedure as a model.

METHODS

One hundred seventy-four colon cancer patients underwent open oncologic colon resection and SLN procedure according to a standardized protocol. For the fake SLN procedure, blue dye was injected ex vivo, into the subserosa of a nontumor-bearing segment of the resected colon in 37 unselected patients. Three levels of each SLN were stained with H&E and with the pancytokeratin marker AE1/AE3 and were analyzed for the presence of cytokeratin positive cells.

RESULTS

Identification of fake SLN was successful in 32 of the 37 patients (86 %). Seventy fake SLN were histologically confirmed. The median number of fake SLN was 2 per patient (range 1-8). None of the fake SLN showed any disseminated epithelial cells.

CONCLUSIONS

The present prospective study provides compelling evidence that blue dye injection during sentinel lymph node procedure for colon cancer does not induce epithelial cell dissemination to the sentinel lymph nodes. Therefore, isolated tumor cells in sentinel lymph nodes result from a true metastatic process.

The role of sentinel lymph node in colon cancer evolution

INTRODUCTION

The aim of this study is to evaluate the sentinel lymph node mapping (SLNM) with methylene blue staining "ex vivo" in colon cancer, as well as calculate the upstaging obtained by the determination of micrometastases and its correlation with the evolution of the disease.

METHODS

Between 2008 and 2011, 101 patients with colon cancer undergoing resection were studied prospectively with SLNM and detection of micrometastases. The correlation of SLN micrometastases with the disease evolution was evaluated in patients with a follow-up of more than one year.

RESULTS

The SLNM rate was 92 cases (91%). Only SLN was positive for micrometastases in 9 cases, with a 14% upstaging. The incidence of false negatives was 9 patients (10%). Mean follow of N0 patients (n=74) was 38 months. The SLN- (negative) group (65 patients) had a recurrence rate of 4 patients (7%), whereas this rate was 2 patients (22%) in the group of SLN+(positive) (9 patients), but without significant differences. No differences in survival were observed.

CONCLUSIONS

SLNM is a reproducible technique without significant increase in time and costs. Upstaging was obtained in 14% of patients staged as N0 by conventional technique. At follow-up of N0 patients with SLN+there seems to be a higher rate of recurrence, which could change the guidelines of adjuvant treatment, but we must interpret the results it with caution because the sample is small.

[The intraoperative study of the sentinel lymph node was made possible through molecular analysis: a new concept and new applications for colon cancer?]

Sentinel lymph node (SLN) is a concept but also a technical possibility that can be studied and applied to almost all organs with cancer. For colorectal cancer surgery, some possibilities of using the SLN are possible, other implausible and some completely new especially aware of possible analysis of SLN by a molecular biology technique. The orientation of dissection or "lymph road mapping" can be designed for this case or the surgeon may want to limit his actions, particularly in patients with a history of colonic surgical resection, to keep the digestive function in maintaining vascular axes considered not involved in the metastatic process. The use of the single analysis of SLN to determine the positive or negative status of the cleaning has failed because of the frequency of false negatives in part to the size of colic advanced cancers at diagnosis. The use of "ultra-stading" by multiple section or exhaustion of the block, can lead to reconsider a stage N0 to N1 as a point, if the analysis technique remains in HES. Unlike the "ultra-stading" by RT- PCR or immunohistochemistry was even more discussed and seems not equivalent in terms of prognosis and therefore no giving formally justification for adjuvant therapy. Currently, a new technique for molecular biology, named "OSNA", allows an analysis of all the SLN in less than 45 minutes. It is therefore possible to obtain during surgery analysis of a node with the same level of information than traditional analysis using HES. If this node is positive and if the strategy in case of positive lymph nodes was determined prior for this patient, it is possible to anticipate this strategy and place after colectomy during the same anesthesia, venous access quickly to start postoperative chemotherapy. This new technique for analyzing lymph applied to the SLN opens a new potential application of this concept in digestive oncology.

Micrometastatic cancer cells in lymph nodes, bone marrow, and blood: Clinical significance and biologic implications

Cancer metastasis may be regarded as a progressive process from its inception in the primary tumor microenvironment to distant sites by way of the lymphovascular system. Although this type of tumor dissemination often occurs in an orderly fashion via the sentinel lymph node (SLN), acting as a possible gateway to the regional lymph nodes, bone marrow, and peripheral blood and ultimately to distant metastatic sites, this is not a general rule as tumor cells may enter the blood and spread to distant sites, bypassing the SLN. Methods of detecting micrometastatic cancer cells in the SLN, bone marrow, and peripheral blood of patients have been established. Patients with cancer cells in their SLN, bone marrow, or peripheral blood have worse clinical outcomes than patients with no evidence of spread to these compartments. The presence of these cells also has important biologic implications for disease progression and the clinician's understanding of the process of cancer metastasis. Further characterization of these micrometastatic cancer cells at each stage and site of metastasis is needed to design novel selective therapies for a more "personalized" treatment.

Simultaneous mapping of pan and sentinel lymph nodes for real-time image-guided surgery

The resection of regional lymph nodes in the basin of a primary tumor is of paramount importance in surgical oncology. Although sentinel lymph node mapping is now the standard of care in breast cancer and melanoma, over 20% of patients require a completion lymphadenectomy. Yet, there is currently no technology available that can image all lymph nodes in the body in real time, or assess both the sentinel node and all nodes simultaneously. In this study, we report an optical fluorescence technology that is capable of simultaneous mapping of pan lymph nodes (PLNs) and sentinel lymph nodes (SLNs) in the same subject. We developed near-infrared fluorophores, which have fluorescence emission maxima either at 700 nm or at 800 nm. One was injected intravenously for identification of all regional lymph nodes in a basin, and the other was injected locally for identification of the SLN. Using the dual-channel FLARE intraoperative imaging system, we could identify and resect all PLNs and SLNs simultaneously. The technology we describe enables simultaneous, real-time visualization of both PLNs and SLNs in the same subject.

Colon resection: is standard technique adequate?

The traditional approach to surgical resection of colonic cancer involves removal of the primary tumor together with the associated lymphovascular pedicle. In an attempt to improve oncological outcomes, several groups have recently published data describing improved outcomes with a more radical surgical approach termed complete mesocolic excision (CME) with central vessel ligation (CVL). Here we critically appraise this new surgical advance and discuss other surgical options suggested to offer improvements over current best practice.

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.

In vivo lymph node mapping and pattern of metastasis spread in locally advanced mid/low rectal cancer after neoadjuvant chemoradiotherapy

PURPOSE

The lymph node status is one of the strongest prognostic determinants in rectal cancers. After chemoradiotherapy (CRT), lymph nodes are difficult to detect. This study aims to evaluate the feasibility of lymph node mapping in the mesorectum after CRT to analyze the pattern of metastasis spread and to assess the reliability of blue dye injection in sentinel lymph node detection.

METHOD

Ten patients with cN+ mid/low RCs after CRT were prospectively enrolled. The protocol scheduled intraoperative blue dye injection, surgery, and specimen examination with fat clearance technique. The mesorectum was divided into three equal "levels" (upper, middle, and lower); each level was divided into three equal "sectors" (right anterolateral, posterior, and left anterolateral). Lymph nodes were defined "small" if ≤5 mm.

RESULTS

Two hundred seventy-six lymph nodes were retrieved in ten patients; 76.5 % were small lymph nodes. Six patients were pN+ (33 metastatic lymph nodes, 76 % small); small lymph node analysis upstaged one patient from N0 to N1 and four patients from N1 to N2. Metastasis distribution across sectors was continuous, without "skip sectors." The blue dye detected the sentinel lymph node in all patients; in half of the cases, it was out of the tumor sector. Blue dye identified 69.7 % of metastatic lymph nodes; its sensitivity decreased together with the metastatic deposit size (84 % macrometastases, 28.6 % micrometastases, 0 % occult tumor cells; p = 0.004).

CONCLUSION

The fat clearance technique should be the standard pathological examination in patients with RCs after CRT; N staging was improved by small lymph node identification. Lymph node metastases have a continuous spread through mesorectal sectors. Blue dye injection is effective in sentinel lymph node detection.

Excellent prognosis of node negative patients after sentinel node procedure in colon carcinoma: a 5-year follow-up study

AIM

Investigate the prognostic impact and clinical relevance of the sentinel node (SN)-procedure in colon carcinoma.

PATIENTS AND METHODS

Between May 2002 and January 2004, the SN-procedure was performed in 55 patients that underwent elective resection for clinically non-advanced colon carcinoma. A control group of 110 patients was identified from a cohort between January 2000 and April 2002. All lymph nodes were analysed by conventional haematoxylin-eosin staining. All negative SNs underwent in-depth analysis using immunohistochemical-staining and automated microscopy with the Ariol-system. Patients with positive lymph nodes were offered adjuvant chemotherapy. All patients were routinely monitored at 6-month intervals and follow-up was more than 5 years.

RESULTS

The SN was successfully identified in 98% of the patients, with 94% sensitivity. In-depth analysis with immunohistochemistry and automated microscopy (Ariol-system) upstaged 3 and 4 patients respectively. When only node-negative patients were analysed, overall 5-year-survival was significantly better in the SN group (91% vs. 76%, p = 0.04). Cancer-specific-mortality was even 0% (vs. 8%, p = 0.08). Disease-free-survival was significantly improved to 96% (vs. 77%, p < 0.01).

CONCLUSIONS

This study describes the prognostic impact of the SN-procedure in colon carcinoma after 5-year-follow-up. Only one patient had recurrent disease after a negative SN procedure (disease-free-survival 96%). These results indicate that the SN-procedure is of prognostic relevance and might be useful to select patients for adjuvant chemotherapy. Patients that are lymph node negative after an SN-procedure have an excellent prognosis and do not need adjuvant treatment.

Factors influencing the success of in vivo sentinel lymph node procedure in colon cancer patients: Swiss prospective, multicenter study sentinel lymph node procedure in colon cancer

BACKGROUND

The sentinel lymph node (SLN) procedure has the potential to provide relevant improvement in nodal staging in colon cancer patients. However, there remains room for improvement for SLN identification and sensitivity. Therefore, the objective of the present investigation was to analyze factors influencing the success of the SLN procedure in colon cancer patients.

METHODS

One hundred seventy-four consecutive colon cancer patients were prospectively enrolled in this multicenter study and underwent in vivo SLN procedure with isosulfan blue 1 % followed by open standard oncologic colon resection. Several patient-, tumor-, and procedure-related factors possibly influencing the SLN identification and sensitivity were analyzed.

RESULTS

Sentinel lymph node identification rate and accuracy were 89.1 and 83.9 %, respectively. Successful identification of SLN was significantly associated with the intraoperative visualization of blue lymphatic vessels (p < 0.001) and with female gender (p = 0.024). True positive SLN results were significantly associated with higher numbers of SLN (p = 0.026) and with pN2 stage (p = 0.004). There was a trend toward better sensitivity in patients with lower body mass index (BMI) (p = 0.050).

CONCLUSIONS

The success of the SLN procedure in colon cancer patients depends on both procedure-related factors (intraoperative visualization of blue lymphatic vessels, high number of SLN identified) and patient factors (gender, BMI). While patient factors can not be influenced, intraoperative visualization of blue lymphatics and identification of high numbers of SLN are key for a successful SLN procedure.

Qualitative and quantitative issues of lymph nodes as prognostic factor in colon cancer

For patients undergoing curative resections for colon cancer, the nodal status represents the strongest prognostic factor, yet at the same time the most disputed issue as well. Consequently, the qualitative and quantitative aspects of lymph node evaluation are thus being scrutinized beyond the blunt distinction between 'node positive' (pN+) and 'node negative' (pN0) disease. Controversy ranges from a minimal or 'least-unit' strategy as exemplified by the 'sentinel node' to a maximally invasive or 'all inclusive' approach by extensive surgery. Ranging between these two extremes of node sampling strategies are factors of quantitative and qualitative value, which may be subject to modification. Qualitative issues may include aspects of lymph node harvest reflected by surgeon, pathologist and even hospital performance, which all may be subject to modification. However, patient's age, gender and genotype may be non-modifiable, yet influence node sample. Quantitative issues may reflect the balance between absolute numbers and models investigating the relationships of positive to negative nodes (lymph node ratio; log odds of positive lymph nodes). This review provides an updated overview of the current controversies and a state-of-the-art perspective on the qualitative and quantitative aspects of using lymph nodes as a prognostic marker in colon cancer.

Lymph node dissection for esophageal cancer

The prevalence of lymph node (LN) metastasis in esophageal cancer (EC) is widely spread to all three fields, namely, to the neck region, the mediastinal region and the abdominal region. Furthermore, the status of LN metastasis has been recognized as a key factor that influences the outcome after EC surgery. Therefore, the latest version of the UICC/AJCC TNM classification (7th edition) applied the number of metastatic LNs as an N factor. However, the precise clinical diagnosis of metastatic LNs is still difficult. This is mainly because there are many micrometastases in EC. Therefore, the Japanese Classification of Esophageal Cancer (10th edition) has not incorporated the number of LN metastases into the N factor for its staging system and the accurate preoperative diagnosis of LN status is currently one of the most important issues to be resolved for EC. Given the frequency and extent of LN metastasis and its significance for the survival, controlling LN metastasis is a rational therapeutic strategy, and an extended LN dissection, such as three-field lymph node dissection may be logical, although appropriate patient selection is necessary. On the other hand, recent arguments have supported a reduction of unnecessary LN dissection in esophagectomy. To curtail unnecessary LN dissection, one of the current topics is sentinel lymph node-guided surgery and is being investigated as part of the next generation surgeries for EC. In this article, recent literatures were reviewed and we discuss the current status of lymph node dissection in EC.

Laparoscopic sentinel lymph node identification in patients with colon carcinoma using a near-infrared dye: description of a new technique and feasibility study

BACKGROUND

After promising results were obtained from studies in large animals, a technique using indocyanine green (ICG) is being introduced for sentinel lymph node (SLN) biopsy in colon cancer patients.

SUBJECTS AND METHODS

Colon cancer patients without clinical signs of metastatic disease, presenting at the VU University Medical Center (Amsterdam, The Netherlands) or Kennemer Gasthuis (Haarlem, The Netherlands), were asked to participate in the study. During laparoscopy, a subserosal injection of 2.5 mg of ICG diluted in 1 mL of 0.9% NaCl plus 2% human albumin was performed using a percutaneously inserted long rigid or flexible needle. After injection, a near-infrared laparoscope (Olympus Corp., Tokyo, Japan) was used for lymph flow and SLN visualization. The SLNs were laparoscopically harvested and analyzed by a senior pathologist using multisectioning and immunohistochemistry.

RESULTS

Fourteen patients were included (six women, eight men), with a median age of 75.5 (interquartile range [IQR], 67.8-81.0) years and a median body mass index of 25.1 (IQR, 22.7-26.0) kg/m(2). Median tumor diameter was 4.5 (IQR, 3.4-7.0) cm. At least one SLN was identified in all patients, with a median number of 2.0 (IQR, 2.0-3.3) SLNs. The median time between injection and identification of the SLN was 15.0 (IQR, 13.3-29.3) minutes. Positioning of the needle tip into the subserosal layer was found to be more effective using the flexible needle. When this flexible needle was used, less spill of dye was observed. All SLNs were negative. We observed four false-negative nodes, all after using a rigid needle. None of the patients showed an adverse reaction to the ICG injection.

CONCLUSIONS

Preliminary results of laparoscopic sentinel node identification using a near-infrared dye show this procedure is safe and feasible. It was possible to detect lymph nodes in all patients. Large tumor size, drainage to adjacent lymphatic vessels, and the use of a rigid needle might contribute to false-negative nodes.

[Sentinel lymph node biopsy technique in colon cancer. Experience in 125 cases]

INTRODUCTION

The level of lymph node involvement is the most important factor in staging colorectal cancer without metastasis. Sentinel lymph node mapping identifies the node(s) that most accurately reflect the lymph node status of patients, and intensive techniques that improve staging can be focused on these nodes. The aim of this study was to assess the efficacy of ex vivo sentinel lymph node mapping in the staging of colon cancer.

MATERIALS AND METHODS

A prospective study was conducted on 125 patients from the Alava-Txagorritxu University Hospital Health Region (Alava), who were diagnosed prior to surgery with colon cancer without distant metastasis from September 2009 to December 2011. Ex vivo sentinel lymph node mapping with methylene blue was use in these patients to study the sentinel nodes with multiple slices using immunohistochemical techniques and haematoxylin-eosin staining. A comparative study was also performed based on a control group of 170 patients staged with conventional techniques, and involving a single slice and haematoxylin-eosin staining.

RESULTS

The sentinel lymph node identification rate was 98%, with 5.6% false negatives. Upstaging occurred in 14.2% of cases compared to the group studied using conventional techniques (P=.006).

CONCLUSIONS

Ex vivo sentinel lymph node mapping with methylene blue accurately reflects the lymph node status of patients with colon cancer. This approach upstages patients classified as stages i and ii by conventional techniques to stage iii, indicating chemotherapy that may improve their prognosis.

Ex vivo sentinel node mapping in colon cancer combining blue dye staining and fluorescence imaging

BACKGROUND

The sentinel lymph node procedure has been proposed to improve nodal staging in colon cancer patients. The aim of this study was to assess the added value of near-infrared (NIR) fluorescence imaging to conventional blue dye staining for ex vivo sentinel lymph node mapping.

MATERIALS AND METHODS

We included 22 consecutive patients undergoing surgery for colon cancer. After tumor resection, we submucosally injected a premixed cocktail of the near-infrared lymphatic tracer HSA800 and blue dye around the tumor for detection of sentinel lymph nodes. We used the Mini-FLARE imaging system for fluorescence imaging.

RESULTS

In 95% of patients, we identified at least one sentinel lymph node. Overall, a total of 77 sentinel lymph nodes were identified, 77 of which were fluorescent (100%) and 70 of which were blue (91%). Sentinel lymph nodes that were located deeper in the mesenteric fat could easily be located by NIR fluorescence. In four of five patients with lymph node metastases, tumor cells were present in at least one of the sentinel lymph nodes.

CONCLUSIONS

This study shows the successful use and added value of the NIR fluorescence tracer HSA800 to conventional blue dye for the ex vivo sentinel lymph node procedure in colon cancer.

Relative effectiveness and safety of chemotherapy in elderly and nonelderly patients with stage III colon cancer: a systematic review

BACKGROUND

Chemotherapy effectiveness in clinical practice may differ from the efficacy demonstrated in clinical trials, particularly among populations underrepresented in clinical trials, such as elderly patients with cancer. This review aims to examine the relative effectiveness of chemotherapy for stage III colon cancer in elderly versus nonelderly patients.

METHODS

A systematic literature review was conducted using the Agency for Healthcare Research and Quality approach. Literature searches were performed in Medline and Evidence-Based Medicine Reviews databases. Chemotherapy regimens approved for stage III colon cancer were reviewed. Four effectiveness and 15 safety outcomes were extracted.

RESULTS

From 708 identified articles, 25 articles provided data on the relative effectiveness and safety of chemotherapy among elderly versus nonelderly patients. Four of 14 studies showed lower overall survival treatment effects, whereas one of five and one of four studies indicated more favorable treatment effects for time to progression and overall response rate. Grade 3 or 4 adverse events were higher among elderly patients for cardiac disorder (2/5 studies), leukopenia (1/5), neutropenia (4/16), thrombocytopenia (2/13), febrile neutropenia (1/4), infection (2/10), dehydration (2/6), diarrhea (6/20), and fatigue (6/13). Grade 3 or 4 adverse events were lower for neutropenia (2/16 studies), nausea/vomiting (1/16), and neuropathy (1/9).

CONCLUSION

The majority of the evidence suggests that chemotherapy has similar relative effectiveness and safety for patients >65 years of age versus younger patients with stage III colon cancer. When differences are reported, treatment effects are more often worse among the elderly. This review suggests that without other reasons for withholding treatment, elderly patients should receive chemotherapy as often as nonelderly patients.

Endoscopic submucosal dissection and surgical treatment for gastrointestinal cancer

Endoscopic submucosal dissection (ESD) is widely used in Japan as a minimally invasive treatment for early gastric cancer. The application of ESD has expanded to the esophagus and colorectum. The indication criteria for endoscopic resection (ER) are established for each organ in Japan. Additional treatment, including surgery with lymph node dissection, is recommended when pathological examinations of resected specimens do not meet the criteria. Repeat ER for locally recurrent gastrointestinal tumors may be difficult because of submucosal fibrosis, and surgical resection is required in these cases. However, ESD enables complete resection in 82%-100% of locally recurrent tumors. Transanal endoscopic microsurgery (TEM) is a well-developed surgical procedure for the local excision of rectal tumors. ESD may be superior to TEM alone for superficial rectal tumors. Perforation is a major complication of ESD, and it is traditionally treated using salvage laparotomy. However, immediate endoscopic closure followed by adequate intensive treatment may avoid the need for surgical treatment for perforations that occur during ESD. A second primary tumor in the remnant stomach after gastrectomy or a tumor in the reconstructed organ after esophageal resection has traditionally required surgical treatment because of the technical difficulty of ER. However, ESD enables complete resection in 74%-92% of these lesions. Trials of a combination of ESD and laparoscopic surgery for the resection of gastric submucosal tumors or the performance of sentinel lymph node biopsy after ESD have been reported, but the latter procedure requires a careful evaluation of its clinical feasibility.

The effect of colonoscopic tattooing on lymph node retrieval and sentinel lymph node mapping

BACKGROUND

In colorectal cancer (CRC), colonoscopic tattooing is performed to mark the tumor site before laparoscopic surgery.

OBJECTIVE

To determine whether colonoscopic tattooing can be used to refine staging accuracy by increasing the lymph node (LN) yield per specimen and to determine its accuracy as a sentinel LN procedure.

DESIGN

Retrospective, case-control study. All LNs were microscopically examined for the presence of carbon particles.

SETTING

A university hospital and a teaching hospital.

PATIENTS

A consecutive series of 95 tattooed patients who had surgery for CRC between 2005 and 2009. A series of 210 non-tattooed patients who had surgery in the same time period served as controls.

MAIN OUTCOME MEASUREMENTS

Total number of LNs retrieved, detection rate, and sensitivity of tattooing as a sentinel node procedure.

RESULTS

A higher LN yield was observed in patients with preoperative tattooing, median (interquartile range) 15 (10-20) versus 12 (9-16), (P = .014). In multivariable analysis, the presence of carbon-containing LNs was an independent predictive factor for a higher LN yield (P = .002). The detection rate was 71%, with a median of 5 carbon-containing LNs per specimen. If preoperative tattooing was used for sentinel node mapping, the overall accuracy of predicting LN status was 94%. In the 24 N1 cases, there were 4 false-negative procedures (sensitivity 83%).

LIMITATIONS

Retrospective series.

CONCLUSION

After tattooing of CRC, the LN yield was higher than in a control group, and it could be used as a sentinel node procedure with acceptable accuracy rates. Because LN yield and sentinel node mapping are associated with improved diagnostic accuracy of LN involvement, preoperative tattooing can refine staging.

Intra-operative tumour detection and staging in colorectal cancer surgery

AIM

Surgical resection for colorectal cancer involves segmental resection and regional lymphadenectomy. The appropriateness of this 'one-size-fits-all' strategy is questioned as bowel cancer screening programmes result in a shift to earlier stage disease. Currently, the nodal status of a colorectal cancer can only be reliably determined by histopathological examination of the resected specimen. New methods of intra-operative staging are required to allow surgical resection to be tailored to the stage of the disease.

METHOD

A literature search was performed of PubMed and Embase databases using the terms 'colon' OR 'colorectal' AND 'intra-operative detection' OR 'intra-operative staging' OR 'intra-operative detection' OR 'radioimmunoguided surgery'. Articles published between January 1980 and January 2012 were included. Technologies that have the potential to allow intra-operative staging and treatment stratification were identified and further searches performed.

RESULTS

Established techniques such as sentinel lymph node mapping and radioimmunoguided surgery have benefited from combination with other technologies to allow real-time intra-operative staging. Intra-operative fluorescence, using naturally fluorescent biomarkers or fluorescent tumour probes, probably offers the most practical means of intra-operative lymph node staging and may be facilitated using nanotechnology. Optical coherence tomography and real-time elastography have the potential to provide an in vivo'virtual biopsy'.

CONCLUSION

Technological advances may allow accurate intra-operative lymph node staging to facilitate tailored surgical resection. This may become the next paradigm shift in colorectal cancer surgery.

Prognostic relevance of occult metastases detected by cytokeratin 20 and mucin 2 mRNA levels in sentinel lymph nodes from colon cancer patients

PURPOSE

To investigate the prognostic value of occult metastases detected by quantitative measurements of candidate biomarkers in sentinel lymph nodes (SLNs) from patients curatively resected for colon cancer.

METHODS

Resection specimens from consecutive patients undergoing surgery for localized colon cancer were subjected to ex vivo SLN mapping. SLNs were examined for the presence of metastases by routine hematoxylin-erythrosin-safranin staining and by cytokeratin 20 (CK20) and mucin 2 (MUC2) mRNA quantification. The patients were stratified according to KRAS and BRAF mutation status and microsatellite instability status in their primary tumors. Survival end points were analyzed by Kaplan-Meier survival estimates and log-rank tests.

RESULTS

A total of 817 SLNs were identified in 206 (97 %) of the 213 included patients. Routine histological examination of SLNs and other regional lymph nodes identified 63 patients with positive nodes (pN+), of which 42 (67 %) were positive in one or more SLNs (sensitivity 67 %, false-negative rate 33 %). On the basis of the CK20 and MUC2 mRNA levels in SLNs, occult metastases were suggested in 86 (60 %) and 52 (36 %) of the 143 otherwise LN-negative (pN0) patients, respectively. Survival analysis with a median 3.6-year follow-up revealed that MUC2 mRNA quantification had significant prognostic value in SLNs from all patients; however, occult SLN metastasis detection did not.

CONCLUSIONS

Occult SLN metastases detected by CK20 and MUC2 mRNA quantification had limited prognostic value.

Ex vivo localization and immunohistochemical detection of sentinel lymph node micrometastasis in patients with colorectal cancer can upgrade tumor staging

BACKGROUND

It is not clear if sentinel lymph node (SLN) mapping can improve outcomes in patients with colorectal cancers. The purpose of this study was to determine the prognostic values of ex vivo sentinel lymph node (SLN) mapping and immunohistochemical (IHC) detection of SLN micrometastasis in colorectal cancers.

METHODS

Colorectal cancer specimens were obtained during radical resections and the SLN was identified by injecting a 1% isosulfan blue solution submucosally and circumferentially around the tumor within 30 min after surgery. The first node to stain blue was defined as the SLN. SLNs negative by hematoxylin and eosin (HE) staining were further examined for micrometastasis using cytokeratin IHC.

RESULTS

A total of 54 patients between 25 and 82 years of age were enrolled, including 32 males and 22 females. More than 70% of patients were T3 or above, about 86% of patients were stage II or III, and approximately 90% of patients had lesions grade II or above. Sentinel lymph nodes were detected in all 54 patients. There were 32 patients in whom no lymph node micrometastasis were detected by HE staining and 22 patients with positive lymph nodes micrometastasis detected by HE staining in non-SLNs. In contrast only 7 SLNs stained positive with HE. Using HE examination as the standard, the sensitivity, non-detection rate, and accuracy rate of SLN micrometastasis detection were 31.8% (7/22), 68.2% (15/22), and 72.2%, respectively. Micrometastasis were identified by ICH in 4 of the 32 patients with HE-negative stained lymph nodes, resulting in an upstaging rate 12.5% (4/32). The 4 patients who were upstaged consisted of 2 stage I patients and 2 stage II patients who were upstaged to stage III. Those without lymph node metastasis by HE staining who were upstaged by IHC detection of micrometastasis had a significantly poorer disease-free survival (p = 0.001) and overall survival (p = 0.004).

CONCLUSION

Ex vivo localization and immunohistochemical detection of sentinel lymph node micrometastasis in patients with colorectal cancer can upgrade tumor staging, and may become a factor affecting prognosis and guiding treatment.

Systematic review of sentinel lymph node mapping procedure in colorectal cancer

BACKGROUND

The clinical impact of sentinel lymph node (SN) biopsy in colorectal cancer is still controversial. The aim of our study was to determine the accuracy of this procedure from published data and to identify factors that contribute to the conflicting reports.

METHODS

A systematic search of the Medline, Embase, and Cochrane databases up to July 2011 revealed 98 potentially eligible studies, of which 57 were analyzed including 3,934 patients (3,944 specimens).

RESULTS

The pooled SN identification rate was 90.7% (95% CI 88.2-93.3), with a significant higher identification rate in studies including more than 100 patients or studies using the ex vivo SN technique. The pooled sensitivity of the SN procedure was 69.6% (95% CI 64.7-74.6). Including the immunohistochemical findings increased the pooled sensitivity of SN procedure to 80.2% (95% CI 4.7-10.7). Subgroups with significantly higher sensitivity could be identified: ≥4 SNs versus <4 SNs (85.2 vs. 66.3%, p = 0.003), colon versus rectal cancer (77.6 vs. 65.7%, p = 0.04), early T1 or T2 versus advanced T3 or T4 carcinomas (93.4 vs. 58.8%, p = 0.01). Serial sectioning and immunohistochemistry resulted in a mean upstaging of 18.9% (range 0-50%). True upstaging defined as micrometastases (pN1mi+) rather than isolated tumor cells (pN0itc+) was 7.7%.

CONCLUSIONS

The SN procedure in colorectal cancer has an overall sensitivity of 70%, with increased sensitivity and refined staging in early-stage colon cancer. Because the ex vivo SN mapping is an easy technique it should be considered in addition to conventional resection in colon cancer.

Analysis of sentinel lymph node biopsy results in colon cancer in regard of the anthropometric features of the population and body composition assessment formulas

Purpose

The aim of the study was to assess sentinel lymph node biopsy (SLNB) results in colon cancer (CC) regarding basic anthropometric features of the studied population and their derivatives calculated using mathematical formulas.

Methods

One hundred three SLNBs in CC have been analysed. Various indicators were calculated for every patient using mathematical formulas: BMI, Roher’s index, lean body weight, body fat percentage and body weight/ideal body weight for a given height ratios using the following formulas: Broca’s, Broca’s ideal weight, Broca–Brugsch, Lorenz’s, Potton’s, Devine’s, Robinson’s, Miller’s and Hamwi. The results were compared with accuracy, sensitivity and false negative results percentage by means of ROC curves and the test for structure indicators (for determined cut-off points).

Results

No statistically significant relationship between the results and patients' sex or age were found. ROC curve analysis did not reveal statistically significant relationships between the obtained results and indicators calculated on the basis of growth and weigh (all p > 0.05). The analyses of sensitivity and accuracy with determined cut-off point, in spite of differences amounting to 19 % (analysis of lean body weight/weight ratio), showed no statistical significance for any of the relationships (all p > 0.05).

Conclusions

No indicator with high diagnostic and prognostic value has been found. The problem of qualifying patients for SLNB in CC in regard of the anthropometric features of the population and body composition assessment formulas remains open and requires further analysis on larger populations.

Isolated tumor cells in regional lymph nodes as relapse predictors in stage I and II colorectal cancer

PURPOSE

Lymph node (LN) involvement is the most important prognostic factor in colorectal cancer (CRC), and pN-positive status identifies patients who require adjuvant chemotherapy. Approximately 15% to 20% of patients without nodal metastases (pN0) develop recurrent disease. In this study, we tested the prognostic significance of isolated tumor cells (ITCs) in LNs of patients with pN0 CRC (stages I and II).

PATIENTS AND METHODS

ITCs in LNs regional to CRC were assessed in 312 consecutive patients with pN0 CRC who were followed up clinically and/or endoscopically for at least 6 months after surgery (mean, 67 months; median, 64 months; range, 8 to 102 months). LNs were dissected from gross surgical specimens according to a standardized protocol (with a mean of 17 LNs per patient; range, five to 107 LNs). In all, 5,313 pN0 LNs were collected and assessed by using cytokeratin immunostaining in two serial histology sections from each LN, which amounting to a total of 10,626 specimens. The correlation between ITC status and cancer recurrence was tested by using univariate and multivariate statistics.

RESULTS

ITCs were documented in 185 of 312 patients (59%). CRC relapsed in 31 of 312 patients (10%), and 25 of 31 recurrences (81%) were documented among ITC-positive patients. CRC recurrence rates among ITC-positive and ITC-negative patients were 14% (25 of 185 patients) and 4.7% (six of 127 patients), respectively. In both univariate and multivariate analyses, ITC status was the only variable significantly associated with cancer relapse (Cox model; hazard ratio, 3.00; 95% CI, 1.23 to 7.32; P = .013).

CONCLUSION

In patients with pN0 CRC, cancer relapse was significantly associated with ITCs in regional LNs. ITCs should be considered among the clinicobiologic variables that identify high-risk patients who can benefit from adjuvant chemotherapy.

Sentinel lymph node procedure leads to upstaging of patients with resectable colon cancer: results of the Swiss prospective, multicenter study sentinel lymph node procedure in colon cancer

BACKGROUND

The value of the sentinel lymph node (SLN) procedure in colon cancer patients remains a matter of debate. The objective of this prospective, multicenter trial was 3-fold: to determine the identification rate and accuracy of the SLN procedure in patients with resectable colon cancer; to evaluate the learning curve of the SLN procedure; and to assess the extent of upstaging due to the SLN procedure.

METHODS

One hundred seventy-four consecutive colon cancer patients were enrolled onto this prospective trial. They underwent an intraoperative SLN procedure with isosulfan blue 1% injected peritumorally followed by open standard colon resection with oncologic lymphadenectomy. Three levels of each SLN were stained with hematoxylin and eosin (H&E) and immunostained with the pancytokeratin marker AE1/AE3 if H&E was negative.

RESULTS

SLN identification rate and accuracy were 89.1% and 83.9%, respectively. SLN were significantly more likely to contain tumor infiltrates than non-SLN (P < 0.001). Both SLN identification rate (P = 0.021) and the sensitivity of the procedure (P = 0.043) significantly improved with experience. The use of immunohistochemistry in SLN resulted in an upstaging of 15.4% (16 of 104) stage I and II patients considered node-negative in initial H&E analysis.

CONCLUSIONS

The SLN procedure for colon cancer has good identification and accuracy rates, which further improve with increasing experience. Most importantly, the SLN procedure results in upstaging of >15% of node-negative patients. The potential advantage of performing the SLN procedure appears to be particularly important in these patients because they may potentially benefit from adjuvant therapy.

Near infrared fluorescence lymphatic laparoscopy of the colon and mesocolon

During surgery, a surgeon relies on the vision of his eyes and the touch of his hands. While laparoscopic surgery for colon cancer has proven to be safe and effective, it still remains a technically difficult procedure. Although it is associated with reduced haptic feedback, by enforcing the power of visual guidance, the loss of this feedback can be (partly) compensated for. Here we describe how the use of near-infrared dyes and fluorescence laparoscopy could help improve tumour staging and therefore lead to better selection of patients for postoperative adjuvant chemotherapy. More controversially, and analogous to melanoma and breast cancer surgery with sentinel node biopsy, we speculate that local resection with SLN harvesting in early colon cancer might change the therapeutic and surgical strategy in colon cancer.

Sentinel lymph node biopsy in endometrial cancer: meta-analysis of 26 studies

OBJECTIVE

The validity of the sentinel lymph node (SLN) procedure for the assessment of nodal status in patients with endometrial cancer is unclear. We aimed to assess the diagnostic performance of this procedure.

METHODS

We searched the PubMed and Embase databases for studies published before June 1, 2011. Eligible studies had a sample size of at least 10 patients, and reported the detection rate and/or sensitivity of the SLN biopsy.

RESULTS

We identified 26 eligible studies, which included 1101 SLN procedures. The overall weighted-mean number of harvested SLNs was 2.6. The detection rate and the sensitivity were 78% (95% confidence interval [CI]=73%-84%) and 93% (95% CI=87%-100%), respectively. Significant between-study heterogeneity was observed in the analysis of the detection rate (I-squared statistic, 80%). The use of pericervical injection was correlated with the increase of the detection rate (P=0.031). The hysteroscopic injection technique was associated with the decrease of the detection rate (P=0.045) and the subserosal injection technique was associated with the decrease of the sensitivity (P=0.049), if they were not combined with other injection techniques. For the detection rate, significant small-study effects were noted (P<0.001).

CONCLUSIONS

Although SLN biopsy has shown good diagnostic performance in endometrial cancer, such performance should be interpreted with caution because of significant small study effects. Current evidence is not yet sufficient to establish the true performance of SLN biopsy in endometrial cancer.