United States Military Cancer Institute Clinical Trials Group (USMCI GI-01) Randomized Controlled Trial Comparing Targeted Nodal Assessment and Ultrastaging With Standard Pathological Evaluation for Colon Cancer

United States-Based Colorectal Cancer Surgical Trials Lack Representation and Adequate Reporting of Racially and Ethnically Diverse Participants: Systematic Review and Regression Analysis

BACKGROUND

Despite the established National Institute of Health Revitalization Act, which aims to include ethnic and racial minority representation in surgical trials, racial and ethnic enrollment disparities persist.

OBJECTIVE

To assess the proportion of patients from minority races and ethnicities that are included in colorectal cancer surgical trials and reporting characteristics.

DATA SOURCES

Search was performed using MEDLINE (Ovid), Embase, Web of Science, and Cochrane Central.

STUDY SELECTION

Inclusion criteria included 1) trials performed in the United States between January 1, 2000, and May 30, 2022; 2) patients with colorectal cancer diagnosis; and 3) surgical intervention, technique, or postoperative outcome. Trials evaluating chemotherapy, radiotherapy, or other nonsurgical interventions were excluded.

INTERVENTIONS

Pooled proportion and regression analysis was performed to identify the proportion of patients by race and ethnicity included in surgical trials and the association of year of publication and funding source.

MAIN OUTCOME MEASURES

Proportion of trials reporting race and ethnicity and proportion of participants by race and ethnicity included in surgical trials.

RESULTS

We screened 10,673 unique publications, of which 80 were examined in full text. Fifteen studies met our inclusion criteria. Ten (66.7%) trials did not report race, 3 reported races as a proportion of White participants only, and 3 reported 3 or more races. There was no description of ethnicity in 11 (73.3%) trials, with 2 describing "non-Caucasian" as ethnicity and 2 describing only Hispanic ethnicity. Pooled proportion of White participants was 81.3%, of Black participants was 6.2%, of Asian participants was 3.6%, and of Hispanic participants was 3.5%.

LIMITATIONS

A small number of studies was identified that reported racial or ethnic characteristics of their participants.

CONCLUSIONS

Both race and ethnicity are severely underreported in colorectal cancer surgical trials. To improve outcomes and ensure the inclusion of vulnerable populations in innovative technologies and novel treatments, reporting must be closely monitored.

Comparison of Linked Color Imaging and White Light Imaging Colonoscopy for Detection of Colorectal Adenoma Requiring Endoscopic Treatment: A Single-Center Randomized Controlled Trial

BACKGROUND

Linked color imaging (LCI) improves detection of colorectal neoplastic lesions during colonoscopy. However, polyps <5 mm in diameter often do not require resection, and the benefits of LCI are unclear for detection of colorectal polyps ≥5 mm that are indicated for endoscopic resection in clinical practice. This randomized controlled trial compared rates of detection of adenoma polyps, stratified by size, for LCI and white light imaging (WLI).

METHODS

We compared ADR (5 mm-) and PDR (5 mm-), which were defined as the proportion of patients with at least one adenoma or polyp with a diameter of 5 mm or larger in the LCI and WLI groups. Moreover, we estimated ADR and PDR for diameters between 5 and 10 mm (ADR (5-9 mm), PDR (5-9 mm) ) and for diameters larger than 10 mm (ADR (10 mm-), PDR (10 mm-) ).

RESULTS

Data from 594 patients (LCI, n=305; WLI, n=289) were analyzed. ADR (5 mm-) and PDR (5 mm-) were significantly higher in the LCI group than in the WLI group (ADR (5 mm-): P=0.016, PDR (5 mm-): P=0.020). In the assessment of adenoma and polyp size, ADR (5-9 mm) and PDR (5-9 mm) were significantly higher in the LCI group than in the WLI group, although no significant differences were seen in ADR (10 mm-) and PDR (10 mm-) between these groups.

CONCLUSIONS

Polyps ≥5 mm, which are indicated for endoscopic treatment, were more easily visualized with LCI mode than with WLI mode. The improvement in detection rate was obvious for polyps <10 mm, which are easier to miss.

The Value of Sentinel Lymph Node Mapping for the Staging of Node-Negative Colon Cancer: Propensity Score and Mediation Analyses

Objectives

Mediation analysis to assess the protective impact of sentinel lymph node (SLN) mapping on prognosis and survival of patients with colon cancer through a more precise evaluation of the lymph node (LN) status.

Background

Up to 20% of patients with node-negative colon cancer develop disease recurrence. Conventional histopathological LN examination may be limited in describing the real metastatic burden of LN.

Methods

Data of 312 patients with stage I & II colon cancer was collected prospectively. Patients were either staged using intraoperative SLN mapping with multilevel sectioning and immunohistochemical staining of the SLN or conventional techniques. The value of the SLN mapping for the detection of truly node-negative patients was assessed using Cox regression and mediation analysis.

Results

SLN mapping was performed in 143 patients. Disease recurrence was observed in 13 (9.1%) patients staged with SLN mapping and in 27 (16%) staged conventionally. Five-year overall survival (OS) rate was 82.7% (95% confidence interval [CI], 76.5-89.4%) with SLN mapping compared with 65.8% (95% CI, 58.8-73.7%). Five-year cancer-specific survival (CSS) was 95.1% (95% CI, 91.3-99.0%) with SLN mapping compared with 92.5% (95% CI, 88.0-97.2%). Node-negative staging with SLN mapping was associated with significantly better OS (hazard ratio [HR], 0.64; 95% CI, 0.56-0.72; P < 0.001) and CSS (HR, 0.49; 95% CI, 0.39-0.61; P < 0.001) in multivariate analysis. Mediation analysis confirmed a direct protective effect of SLN mapping on OS (HR, 0.78; 95% CI, 0.52-0.96; P < 0.01) and disease-free survival (DFS) (HR, 0.75; 95% CI, 0.48-0.89; P < 0.01).

Conclusions

Staging performed by SLN mapping with multilevel sectioning provides more accurate results than conventional staging. The observed clinically relevant and statistically significant benefit in OS and DFS is explained by a more accurate detection of positive LN by SLN mapping.

Correlation Between Intraoperative and Pathological Findings for Patients Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

This study aimed to examine the correlation between intraoperative and pathological findings for patients undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) and to determine their prognostic significance.

METHODS

Pathological reports of all colorectal cancer (CRC) patients undergoing CRS/HIPEC between 2009 and 2016 were retrospectively reviewed. Pathological specimens lacking tumor cells were defined as negative pathological specimens (NPS). The intraoperative peritoneal cancer index (PCI) and pathological PCI (excluding NPS) were calculated separately. Receiver operating characteristic (ROC) curves were applied to compare the prognostic value of intraoperative and pathological scoring systems.

RESULTS

For 108 CRC patients, 113 CRS/HIPEC procedures were performed. Of 959 pathological specimens examined, 178 (18.6%) were NPS. Overall, 78 procedures (69%) showed NPS. In 52 procedures (46%), the pathological PCI differed from the intraoperative PCI (∆PCI > 0). The ROC areas for intraoperative PCI and pathological PCI were similar in predicting 1-year overall survival (OS), 2-year OS, and 1-year disease-free survival (all p values not significant). However, for the patients with NPS, the number of positive specimens (containing tumor tissue) was superior to intraoperative PCI in predicting 2-year OS (ROC under the curve areas, 0.69 vs. 0.58, respectively; p = 0.012). In addition, a subgroup of 15 patients with a high ∆PCI (≥ 3) had a more favorable median OS than a matched group of 30 patients with similar intraoperative PCI and a ∆PCI of 0 (median survival not reached vs. 21.6 months, respectively; p = 0.05).

CONCLUSIONS

In the majority of CRC CRS/HIPEC procedures, NPS may be found. Among patients with NPS, pathological correlation may have a prognostic significance.

Rectal cancer and the pathologist

Examination of the rectum by pathologists is instrumental in the management of patients affected by rectal carcinoma. That role includes evaluation of multiple gross and microscopic features that convey prognostic implications. The analysis is based on the authors' experience handling rectal specimens along with review of the pertinent literature in these areas: margins of excision, quality of the mesorectum, diligence and techniques to sample lymph nodes, tumor budding, grading of residual amount of carcinoma after preoperative therapy, vascular/perineural invasion, and staging the tumor. Pathologists must communicate the findings in a clear manner. Evaluation of margins and completeness of mesorectum are markers of the quality of surgical excision. The number of lymph nodes obtained and examined is dependent in great part on the diligence of the pathologist finding them in the mesenteric adipose tissue. There are grades for budding and response to prior chemoradiation therapy. The location of vascular invasion (extramural vs. intramural) may predict aggressive behavior. Pathologists proactively are to choose sections of tumor for molecular testing. Meticulous macro- and microscopic evaluation of specimens for rectal carcinoma by pathologist is needed to determine an accurate assessment of staging and other prognostic factors. The modern pathologists play a pivotal part in the care and management of patients suffering from rectal adenocarcinoma. That role goes from the initial histological diagnosis to the gross and microscopic examination of the excised specimens. Based on that examination pathologists issue statements that not only evaluate the quality of the surgical procedure, but also through the application of molecular tests they give light on prognostic factors and information for therapeutic purposes.

Sentinel Lymph Node Mapping with Isosulfan Blue or Indocyanine Green in Colon Cancer Shows Comparable Results and Identifies Patients with Decreased Survival: A Prospective Single-Center Trial

BACKGROUND

Sentinel lymph node (SLN) mapping was reported to improve lymph node staging in colon cancer. This study compares isosulfan blue (IB) with indocyanine green (ICG)-based SLN-mapping and assesses the prognostic value of isolated tumor cells (ITC) and micro-metastases in upstaged patients.

METHODS

A total of 220 stage I-III colon cancer patients were included in this prospective single-center study. In 170 patients, SLN-mapping was performed in vivo with IB and in 50 patients ex vivo with ICG. Three levels of each SLN were stained with H&E. If negative for tumor infiltration, immunostaining for cytokeratin (AE1/3; cytokeratin-19) was performed.

RESULTS

SLN detection rate for IB and ICG was 100 and 98%, respectively. Accuracy and sensitivity was 88 and 75% for IB, 82 and 64% for ICG, respectively (p = 0.244). Overall, 149 (68%) patients were node negative. In these patients, ITC and micro-metastases were detected in 26% (31/129) with IB and 17% (5/29) with ICG (p = 0.469). Patients with ITC and micro-metastases did show decreased overall survival (hazard ratio = 1.96, p = 0.09) compared to node negative disease.

CONCLUSIONS

This study demonstrates a high diagnostic accuracy for both the IB and the ICG SLN-mapping. SLN-mapping upstaged a quarter of patients with node negative colon cancer, and the detected ITC and micro-metastases were an independent negative prognostic marker in multivariate analysis.

The Prognostic Relevance of Sentinel Lymph Node Metastases Assessed by PHGR1 mRNA Quantification in Stage I to III Colon Cancer

BACKGROUND: Regional lymph node (LN) metastasis is a strong and well-established prognostic factor in colon cancer, and recent data suggest a prognostic value of detecting micrometastases and isolated tumor cells in regional LNs. The aim of the study was to investigate the clinical relevance of detecting sentinel lymph node (SLN) metastases in colon cancer patients by measuring the novel metastasis marker PHGR1 mRNA. METHODS: Using quantitative reverse-transcription polymerase chain reaction, we measured PHGR1 mRNA levels in SLNs and primary tumors from 206 patients surgically treated for stage I to III colon cancer and 52 normal LNs from patients undergoing surgery for benign colon diseases. The prognostic impact of these findings was evaluated by Kaplan-Meier analysis and Cox proportional-hazards regression. RESULTS: Compared to normal LNs, elevated PHGR1 mRNA levels were detected in SLNs from 56 (89%) of the 63 patients with pN+ disease. Furthermore, 68 (48%) of the 143 node-negative (pN0) patients had elevated PHGR1 mRNA levels in SLNs, suggesting occult metastases. With a median follow-up of 7.2 years, a significantly shorter recurrence-free (P=.005) and disease-specific (P=.02) survival was observed in patients with elevated PHGR1 mRNA levels in SLNs. Multivariable modeling showed that the SLN PHGR1 mRNA level was an independent prognostic factor. However, when the survival analyses were restricted to pN0 patients, no significant prognostic information was found. CONCLUSION: Measuring PHGR1 mRNA in SLNs provided independent prognostic information on operable colon cancer patients but not in the pN0 subgroup.

Colorectal Cancer:: Imaging Conundrums

Progressive technological advancements in imaging have significantly improved the preoperative sensitivity for the detection of very small foci of regionally- or hematogenously-metastatic colorectal cancer. Unfortunately, this information has not translated to continued linear gains in patient survival, and might even result in the false-positive upstaging of some cases: these are two conundrums in the imaging of colorectal cancer. Both conundrums might be resolved by the widespread use of real-time imaging guidance during operative procedures. This might open the way for the widespread use of fluorodeoxyglucose PET/CT for the initial staging of patients with colorectal cancer.

The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Treatment of Colon Cancer

The American Society of Colon and Rectal Surgeons is dedicated to ensuring high-quality patient care by advancing the science, prevention, and management of disorders and diseases of the colon, rectum, and anus. The Clinical Practice Guidelines Committee is composed of society members who are chosen because they have demonstrated expertise in the specialty of colon and rectal surgery. This committee was created to lead international efforts in defining quality care for conditions related to the colon, rectum, and anus. This is accompanied by developing Clinical Practice Guidelines based on the best available evidence. These guidelines are inclusive and not prescriptive. Their purpose is to provide information on which decisions can be made, rather than to dictate a specific form of treatment. These guidelines are intended for the use of all practitioners, health care workers, and patients who desire information about the management of the conditions addressed by the topics covered in these guidelines. It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all the circumstances presented by the individual patient.

Intranodal Mapping Using Carbon Dye Results in More Accurate Lymph Node Staging in Colon Cancer Patients

INTRODUCTION

Small nodal tumor infiltrates (SNTI)-defined as isolated tumor cells and micrometastases-are associated with worse disease-free and overall survival in stage I and II colon cancer patients. Their detection, however, remains challenging. The objective of the present study was to evaluate whether there is a correlation between the location of SNTI and phagocytosed carbon dye particles in sentinel lymph nodes (SLN) of colon cancer patients.

MATERIALS AND METHODS

Isosulfan blue and carbon dye were injected intraoperatively near the tumor to mark the SLN. Serial sections of SLN were stained with hematoxylin-eosin and immunohistochemistry. Intranodal distribution of phagocytosed carbon particles was compared to the presence of SNTI.

RESULTS

Of a cohort of 159 patients, 24 patients had SNTI in their lymph nodes (LN). SNTI were found in a total of 116 LN of which 66 were SLN and 50 were non-SLN. In 59, these 116 LN with SNTI phagocytosed carbon dye were found (50.9 %). Phagocytosed carbon dye was identified significantly more often in SLN (49 of 66 SNTI positive SLN) compared to 10 of 50 SNTI positive non-SLN (p < 0.001). In 52 out of 59 LN (88.1 %), phagocytosed carbon dye was in close proximity to SNTI.

CONCLUSIONS

In the majority of patients, SNTI are located in the same SLN compartment as phagocytosed carbon dye particles. Our investigation provides evidence that the use of carbon dye facilitates SNTI detection and improves LN staging in colon cancer. Therefore, the concept of intranodal mapping-which has been previously described for melanoma-can be extended to colon cancer patients.

Isolated tumor cells in stage I & II colon cancer patients are associated with significantly worse disease-free and overall survival

BACKGROUND

Lymph node (LN) involvement represents the strongest prognostic factor in colon cancer patients. The objective of this prospective study was to assess the prognostic impact of isolated tumor cells (ITC, defined as cell deposits ≤ 0.2 mm) in loco-regional LN of stage I & II colon cancer patients.

METHODS

Seventy-four stage I & II colon cancer patients were prospectively enrolled in the present study. LN at high risk of harboring ITC were identified via an in vivo sentinel lymph node procedure and analyzed with multilevel sectioning, conventional H&E and immunohistochemical CK-19 staining. The impact of ITC on survival was assessed using Cox regression analyses.

RESULTS

Median follow-up was 4.6 years. ITC were detected in locoregional lymph nodes of 23 patients (31.1%). The presence of ITC was associated with a significantly worse disease-free survival (hazard ratio = 4.73, p = 0.005). Similarly, ITC were associated with significantly worse overall survival (hazard ratio = 3.50, p = 0.043).

CONCLUSIONS

This study provides compelling evidence that ITC in stage I & II colon cancer patients are associated with significantly worse disease-free and overall survival. Based on these data, the presence of ITC should be classified as a high risk factor in stage I & II colon cancer patients who might benefit from adjuvant chemotherapy.

Global cancer surgery: delivering safe, affordable, and timely cancer surgery

Surgery is essential for global cancer care in all resource settings. Of the 15.2 million new cases of cancer in 2015, over 80% of cases will need surgery, some several times. By 2030, we estimate that annually 45 million surgical procedures will be needed worldwide. Yet, less than 25% of patients with cancer worldwide actually get safe, affordable, or timely surgery. This Commission on global cancer surgery, building on Global Surgery 2030, has examined the state of global cancer surgery through an analysis of the burden of surgical disease and breadth of cancer surgery, economics and financing, factors for strengthening surgical systems for cancer with multiple-country studies, the research agenda, and the political factors that frame policy making in this area. We found wide equity and economic gaps in global cancer surgery. Many patients throughout the world do not have access to cancer surgery, and the failure to train more cancer surgeons and strengthen systems could result in as much as US $6.2 trillion in lost cumulative gross domestic product by 2030. Many of the key adjunct treatment modalities for cancer surgery--e.g., pathology and imaging--are also inadequate. Our analysis identified substantial issues, but also highlights solutions and innovations. Issues of access, a paucity of investment in public surgical systems, low investment in research, and training and education gaps are remarkably widespread. Solutions include better regulated public systems, international partnerships, super-centralisation of surgical services, novel surgical clinical trials, and new approaches to improve quality and scale up cancer surgical systems through education and training. Our key messages are directed at many global stakeholders, but the central message is that to deliver safe, affordable, and timely cancer surgery to all, surgery must be at the heart of global and national cancer control planning.

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.

Prognostic Effect of Ultra-Staging Node-Negative Colon Cancer Without Adjuvant Chemotherapy: A Prospective National Cancer Institute-Sponsored Clinical Trial

BACKGROUND

We recently reported, in a prospective randomized trial, that ultra-staging of patients with colon cancer is associated with significantly improved disease-free survival (DFS) compared with conventional staging. That trial did not control for lymph node (LN) number or adjuvant chemotherapy use.

STUDY DESIGN

The current international prospective multicenter cooperative group trial (ClinicalTrials.gov identifier NCT00949312; "Ultra-staging in Early Colon Cancer") evaluates the 12-LN quality measure and nodal ultra-staging impact on DFS in patients not receiving adjuvant chemotherapy. Eligibility criteria included biopsy-proven colon adenocarcinoma; absence of metastatic disease; >12 LNs staged pathologically; pan-cytokeratin immunohistochemistry (IHC) of hematoxylin and eosin (H&E)-negative LNs; and no adjuvant chemotherapy.

RESULTS

Of 445 patients screened, 203 patients were eligible. The majority of patients had intermediate grade (57.7%) and T3 tumors (64.9%). At a mean follow-up of 36.8 ± 22.1 months (range 0 to 97 months), 94.3% remain disease free. Recurrence was least likely in patients with ≥12 LNs, H&E-negative LNs, and IHC-negative LNs (pN0i-): 2.6% vs 16.7% in the pN0i+ group (p < 0.0001).

CONCLUSIONS

This is the first prospective report to demonstrate that patients with optimally staged node-negative colon cancer (≥12 LNs, pN0i-) are unlikely to benefit from adjuvant chemotherapy; 97% remain disease free after primary tumor resection. Both surgical and pathologic quality measures are imperative in planning clinical trials in nonmetastatic colon cancer.

Ordo ab Chao: framework for an integrated disease report

CONTEXT

The volume of information that must be assimilated to appropriately manage patients with complex or chronic disease can make this task difficult because of the number of data points, their variable temporal availability, and the fact that they may reside in different systems or even institutions. OBJECTIVE .- To outline a framework for building an integrated disease report (IDR) that takes advantage of the capabilities of electronic reporting to create a single, succinct, interpretative report comprising all disease pertinent data.

DESIGN

Disease pertinent data of an IDR include pathology results, laboratory and radiology data, pathologic correlations, risk profiles, and therapeutic implications. We used cancer herein as a representative process for proposing what is, to our knowledge, the first example of standardized guidelines for such a report. The IDR was defined as a modular, dynamic, electronic summary of the most current state of a patient in regard to a particular illness such as lung cancer or diabetes, which includes all information relevant for patient management.

RESULTS

We propose the following 11 core data concepts that an IDR should include: patient identification; patient demographics; disease, diagnosis, and prognosis; tumor board dispositions and decisions; graphic timeline; preresection workup and therapy; resection workup; interpretative comment summarizing pertinent findings; biobanking data; postresection workup; and disease and patient status at follow-up.

CONCLUSIONS

A well-executed IDR should improve patient care and efficiency for health care team members. It would demonstrate the added value of pathology interpretation and likely contribute to a reduction in errors and improved patient safety by decreasing the risk that important data will be overlooked.

Value of primary tumor gene signatures in colon cancer when national quality standards are adhered to: preliminary results of an international prospective multicenter trial

BACKGROUND

The purpose of this study was to determine if gene signatures are informative in colon cancer (CC) when National Quality Standards (NQS) are adhered to. Several studies have demonstrated the prognostic potential of gene signatures in primary CC. This has never been evaluated prospectively with adherence to NQS.

METHODS

This was a prospective, international, multicenter trial. Eligibility criteria were: no distant metastasis, ≥12 lymph nodes (LNs), and no adjuvant chemotherapy for LN-negative CC. RNA from frozen tumor samples was considered reliable if RNA Integrity Number >9. Using an Agilent whole human genome array, 44,000 genes were analyzed in primary tumors for differential gene expression (DGE). ANOVA applied at 2-fold expression level was performed in at least 8 experiments to obtain the DGEs.

RESULTS

Molecular analysis was completed in 113 of 128 patients. With median follow-up of 27 months, 11.5 % recurred within 3 years after surgery. Significant DGE was identified in recurrent tumors reflected by upregulation (UR) in cellular proliferation and by downregulation (DR) in prodifferentiating panel of 9 genes, independent of T or N classification. By multivariate analysis 3-year disease-free survival was 12.5 % in the UR/DR group versus 93.4 % in the non-UR/DR group (p < .0001; HR = 24.2; 95 % CI 4.8-120.4).

CONCLUSIONS

This is the first prospective trial to evaluate gene signatures in CC with adherence to a 12-node minimum quality standard. Certain molecular pathways may be prognostically relevant if both surgery and pathology are standardized, regardless of T or N classification. Careful consideration should be made to include surgical quality measures when planning clinical trials to evaluate the true effect of molecular markers in CC.

[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.

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.

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.