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

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.

The mesocolic apical fragment in complete mesocolic excision colectomies: Should it be analysed separately? A proof-of-concept study

AIM

The aim of this work is to describe a protocol and assess the feasibility of harvesting and analysing the mesocolic apical fragment (MAF) for the presence of central lymph node (LN) metastasis and extra lymphatic free tumour cells in a random subgroup extracted from a cohort of complete mesocolic excision colectomies with central vascular ligation.

METHOD

Forty-seven patients diagnosed with colorectal cancer were included. A 2/2 cm pyramid of tissue was cut around the central tie and sent for pathological examination. The MAF was sectioned into 16 slices. High-definition images were taken from the slices which were merged into a panoramic three-dimensional image of the MAF. The distribution of LNs in the MAF was quantified. Immunohistochemistry staining for cytokeratin 14 was used to identify isolated tumour cells and micrometastases in the extranodal tissue.

RESULTS

No tumoural cells migrating through the apical zone, outside of the LNs, were identified. Margins of resection, mesocolic tissue and LNs were all negative in the subgroup of ultrastaged MAFs. The number of examined central LNs varied between 0 and 24, with positive MAF LNs being identified only in pN2 stages. The rate of positive apical LNs in our cohort was 4.2% (n = 2).

CONCLUSIONS

The MAF can be easily extracted from standard specimens, allowing for accurate analysis of lymphatic and extra-nodal tumour cells on the central resection margins, in central LNs and in the apical mesocolic tissue. Future research on larger cohorts is required to establish if analysing the MAF has an impact on patient staging, prognosis and management.

Comparing 5-Year Survival Rates Before and After Re-stratification of Stage I-III Right-Sided Colon Cancer Patients by Establishing the Presence/Absence of Occult Tumor Cells and Lymph Node Metastases in the Different Levels of Surgical Dissection

BACKGROUND

To establish the impact of re-stratification on the outcomes of patients (stage I-III right-sided colon cancer) based on the presence/absence of occult tumor cells (OTC) and/or metastatic lymph nodes in the different levels of surgical dissection.

METHODS

Consecutive patients were drawn from a multicenter prospective trial. After surgery, the surgical specimen was divided into the D1/D2 and D3 volumes before being further analyzed separately. All lymph nodes were examined with cytokeratin CAM 5.2 immunohistochemically. Lymph nodes containing metastases and OTC (micrometastases; isolated tumor cells) were identified. Re-stratification was as follows: RS1, stages I/II, no OTC in D1/D2 and D3 volumes; RS2, stages I/II, OTC in D1/D2 and/or D3; RS3, stage III, lymph node metastases in D1/D2, with/without OTC in D3; RS4, stage III, lymph node metastases in D3, with/without OTC in D3.

RESULTS

Eighty-seven patients (39 men, 68.4 + 9.9 years) were included. The standard stratified (SS) group contained the following: stages I/II (SS1) 57 patients; stage III (SS2) 30 patients. Re-stratified (RS) contained RS1 (38), RS2 (19), RS3 (24), and RS4 (6) patients. Lymph node ratio (OTC) RS2: 0.157 D1/D2; 0.035 D3 and 0.092 complete specimens. Lymph node ratio RS3: 0.113 D1/D2; complete specimen 0.056. Overall survival and disease-free survival were p = 0.875 and p = 0.049 for SS and p = 0.144 and p = 0.001 for RS groups, respectively.

CONCLUSION

This re-stratification identifies a patient group with poor prognosis (RS4). Removing this group from SS2 eliminates all the differences in survival between RS2 and RS3 groups. The level of dissection of the affected nodes may have an impact on survival.

CLINICAL TRIAL

"Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multi-Detector Computed Tomography (MDCT) Angiography" registered at http://clinicaltrials.gov/ct2/show/NCT01351714.

The role of sentinel lymph node mapping in colon cancer: detection of micro-metastasis, effect on survival, and driver of a paradigm shift in extent of colon resection

Unlike in breast cancer and melanoma, sentinel lymph node mapping in colon cancer is primarily used as an aid to the pathologist for accurate nodal staging. The study was undertaken to review the incidence of micro-metastasis and its impact on survival when treated with chemotherapy. The study was also undertaken to see if SLNM could guide limited colon resection in early T stage tumor as a paradigm shift. SLNM was done by subserosal injection of a blue dye. SLNs were ultra-staged by multilevel sectioning and remaining Specimen was then examined by conventional method. For the last 245 patients the specimen was divied ex vivo into two segments as segment A containing the tumor bearing portion of the colon and SLNs with attached mesentery, while segment B include distal part of the colon with attached mesentery. Nodal staging was separately examined. Of the 354 Pts, SLNM was successful in 99.9% of Pts with an average no of SLN/ Pt = 2.8 and total nodes 17.8/pt. Survival was directly related negatively with stage and nodal status. Pts with +ve LN did much better with chemotherapy than without chemotherapy. With 245 Pts, specimen A Vs B, no Pts had +ve node in specimen B with -ve LN in specimen A. SLNM results in more node/Pt, more positive node/Pt ,and more micro-metastasis who when treated with chemotherapy survive longer. Limited segmental resection in early T stage is possible when done with guidance by SLNM without compromising biology.

Identification of nodal micrometastasis in colorectal cancer using deep learning on annotation-free whole-slide images

Detection of nodal micrometastasis (tumor size: 0.2-2.0 mm) is challenging for pathologists due to the small size of metastatic foci. Since lymph nodes with micrometastasis are counted as positive nodes, detecting micrometastasis is crucial for accurate pathologic staging of colorectal cancer. Previously, deep learning algorithms developed with manually annotated images performed well in identifying micrometastasis of breast cancer in sentinel lymph nodes. However, the process of manual annotation is labor intensive and time consuming. Multiple instance learning was later used to identify metastatic breast cancer without manual annotation, but its performance appears worse in detecting micrometastasis. Here, we developed a deep learning model using whole-slide images of regional lymph nodes of colorectal cancer with only a slide-level label (either a positive or negative slide). The training, validation, and testing sets included 1963, 219, and 1000 slides, respectively. A supercomputer TAIWANIA 2 was used to train a deep learning model to identify metastasis. At slide level, our algorithm performed well in identifying both macrometastasis (tumor size > 2.0 mm) and micrometastasis with an area under the receiver operating characteristics curve (AUC) of 0.9993 and 0.9956, respectively. Since most of our slides had more than one lymph node, we then tested the performance of our algorithm on 538 single-lymph node images randomly cropped from the testing set. At single-lymph node level, our algorithm maintained good performance in identifying macrometastasis and micrometastasis with an AUC of 0.9944 and 0.9476, respectively. Visualization using class activation mapping confirmed that our model identified nodal metastasis based on areas of tumor cells. Our results demonstrate for the first time that micrometastasis could be detected by deep learning on whole-slide images without manual annotation.

Comparison of Short-term Results after Laparoscopic Complete Mesocolic Excision and Standard Colectomy for Right-Sided Colon Cancer: Analysis of a Western Center Cohort

Purpose

Laparoscopic complete mesocolic excision (CME) right colectomy is a technically demanding procedure infrequently employed in Western centers. This retrospective cohort study aims to analyze the safety of laparoscopic CME colectomy compared to standard colectomy for right-sided colon cancer in a Western series.

Methods

Prospectively collected data from 60 patients who underwent laparoscopic CME right colectomy were compared to the ones of 55 patients who underwent laparoscopic standard right colectomy.

Results

No differences in clinical characteristics were observed between the CME and standard right colectomy groups. No differences were demonstrated in terms of blood loss (P = 0.060), intraoperative complications (P = 1), conversion rate (P = 0.102), and operative time (P = 0.473). No deaths were observed in either group, while complication rate was 40.0% in the CME and 49.1% in the standard group (P = 0.353). Severe complications occurred in 10.0% vs. 9.1% (P = 0.842), redo surgery in 5.0% vs. 7.3% (P = 0.708), and unplanned readmission in 5.0% vs. 5.5% (P = 1) after CME and standard colectomy, respectively. A significant difference in favor of CME was observed in the total length of specimen (P < 0.001), proximal (P = 0.018), and distal margins (P = 0.037). The number of lymph nodes harvested was significantly higher in the CME group (27 vs. 22, P = 0.037).

Conclusion

In Western series, where patients have less favorable clinical characteristics, laparoscopic CME allows to obtain better quality surgical specimens and comparable short-term outcomes compared to standard right colectomy.

Sentinel-Lymph-Node Multicenter Trials

Well executed multicenter clinical trials often provide significant evidence and support for, or against, foundational aspects of clinical procedures perceived to improve clinical management of a medical condition. In this review, discussed are reports of multicenter clinical trials designed to investigate sentinel lymph node biopsy procedures in seven types of cancer: breast, melanoma, head and neck, gastric, colon, uterine, and vulvar-with focus on the most recent reports of the hypotheses, objectives, parameters, data, results, implications, and impacts of the included trials. Such trials generally enroll more subjects, in shorter time periods, than do single-center studies. Such studies generally also have greater diversities among investigator practitioners and investigative environments than do single-center studies. The greater number of subjects provides more power to statistical analyses performed in such studies. The more rapid accrual usually results in data being more consistently acquired. The diversities of practitioners and environments may produce results that are more conservative than might be obtained from more "focused" studies; however, diversities in a study often identify implicitly results that are more robust-that is results applicable by more practitioners and applicable in more environments.

In vivo sentinel lymph node identification using fluorescent tracer imaging in colon cancer: A systematic review and meta-analysis

INTRODUCTION

The use of fluorescence might improve the performance of the sentinel lymph node procedure in patients with colon cancer. This systematic review was conducted to gain insight in the performance and applicability of the sentinel lymph node procedure using fluorescence.

METHOD

A systematic literature search was performed. Databases were searched for prospective studies concerning sentinel node identification using fluorescence in colon cancer. Detection rate, accuracy rate and sensitivity of the sentinel lymph node procedure were calculated for early stage (T1-T2) and more invasive (T3-T4) tumours.

RESULTS

Analyses of five included studies showed for respectively T3-T4 and T1-T2 tumours a detection rate of 90 % and 91 %, an accuracy rate of 77 % and 98 %, and a sensitivity of 30 % and 80 %.

CONCLUSION

The sentinel lymph node procedure using fluorescence in early stage (T1-T2) colon cancer seems to be promising. Larger cohorts are necessary to confirm these results.

Challenges with colorectal cancer staging: results of an international study

Challenges exist with standardized colorectal cancer reporting despite adoption of the American Joint Committee on Cancer-Staging Manual 8th edition. We performed this study to gauge current practice patterns among a diverse group of surgical pathologists. A web-based questionnaire depicting problematic issues and images related to colorectal carcinoma staging was circulated among 118 surgical pathologists and their responses were correlated with their geographic location (North America vs. Europe vs. others), nature of practice (academic vs. community), the sign-out model (gastrointestinal subspecialty vs. general surgical pathology), and years of professional experience. We found that a substantial number of practicing pathologists ignore recommended-staging criteria in specific settings, particularly with respect to assessment of advanced T stage. Tumors that communicated with the serosa through inflammatory foci were staged as pT3 (49%) or pT4a (51%) by nearly equal numbers of pathologists regardless of level of experience, the sign-out model, or geographic location. Only 65% assigned T stage and margin status based on extent of viable tumor in the neoadjuvant setting. One-third of pathologists, particularly those in Europe (p = 0.015), classified acellular mucin deposits as N1 disease when detected in treatment-naive cases. Nearly 50% of pathologists classified isolated tumor cells (i.e., deposits <0.2 mm) in lymph nodes as metastatic disease (i.e., pN1, p = 0.02). Our results suggest that pathologists ignore recommendations that are based on insufficient data and apply individualized criteria when faced with situations that are not addressed in the American Joint Committee on Cancer Staging Manual 8th edition. These variations in practice limit the ability to compare outcome data across different institutions and draw attention to areas that require further study.

Comparison of Molecular and Histologic Ultrastaging Methods in Sentinel Lymph Node Analysis from Clinical Stage II Colon Cancers

Various studies have demonstrated that occult metastases may be present in patients with clinical stage II colon cancer. The objective of this prospective investigation was to compare the performance of molecular analysis and histologic ultrastaging in detecting occult metastases in sentinel lymph nodes (SLNs). SLNs were collected ex vivo during surgery in 29 patients. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) assays were constructed. The results were compared with histologic ultrastaging analysis by hemalum and eosin stain and immunohistochemistry on step serial sections. At least 1 SLN was identified in 76% of the cases. The first hemalum and eosin section identified metastases in 23% of the 22 SLNs. Immunohistochemistry identified isolated tumor cells in 24% of the remaining 17 cases. An overall 73% of the SLNs analyzed by qRT-PCR were positive. Four of them were negative for ultrastaging analysis. qRT-PCR is a powerful tool for the detection of occult metastases in colorectal SLN and seems to be more sensitive than histologic ultrastaging analysis. A larger prospective cohort study is necessary to provide further evidence.

A Review of Current Challenges in Colorectal Cancer Reporting

Context.—

Pathologic assessment of colorectal cancer resection specimens plays an important role in postsurgical management and prognostication in patients with colorectal cancer. Challenges exist in the evaluation and reporting of these specimens, either because of difficulties in applying existing guidelines or related to newer concepts.

Objective.—

To address challenging areas in colorectal cancer pathology and to provide an overview of the literature, current guidelines, and expert recommendations for the handling of colorectal cancer resection specimens in everyday practice.

Data Sources.—

PubMed (US National Library of Medicine, Bethesda, Maryland) literature review; reporting protocols of the College of American Pathologists, the Royal College of Pathologists of the United Kingdom, and the Japanese Society for Cancer of the Colon and Rectum; and classification manuals of the American Joint Committee on Cancer and the Union for International Cancer Control.

Conclusions.—

This review has addressed issues and challenges affecting quality of colorectal cancer pathology reporting. High-quality pathology reporting is essential for prognostication and management of patients with colorectal cancer.

Persistent Problems in Colorectal Cancer Reporting

Tumor stage, as determined by the Tumor, Node, Metastasis (TNM) staging system, is the single most influential factor determining treatment decisions and outcome among patients with colorectal cancer. Several stage-related elements in pathology reports consistently pose diagnostic challenges: recognition of serosal penetration by tumor (ie, pT3 vs pT4a), evaluation of regional lymph nodes, distinction between tumor deposits and effaced lymph nodes, and assessment of tumor stage in the neoadjuvant setting. This article discusses each of these issues in detail and provides practical tips regarding colorectal cancer staging.

Lymph Node Metastasis in Colorectal Cancer

Pathologic examination of lymph nodes in patients with cancer remains crucial for postoperative treatment and prognosis prediction. In this article, the authors aim to review several important and challenging issues regarding lymph node metastasis in colorectal cancer using the AJCC staging manual, College of American Pathologists cancer protocol, as well as the literature. These topics include lymph node staging, the definition and controversies in tumor deposits, isolated tumor cells in lymph node and micrometastasis, lymph node ratio as a prognostic stratification factor, and neoadjuvant treatment effect in rectal cancer. Updates from the most recent AJCC 8th edition are included.

Omission of Adjuvant Chemotherapy Is Associated With Increased Mortality in Patients With T3N0 Colon Cancer With Inadequate Lymph Node Harvest

BACKGROUND

Adjuvant chemotherapy for T3N0 colon cancer is controversial. National guidelines recommend its use in patients with stage II with high-risk features, including lymph node harvest of less than 12, yet this treatment is underused.

OBJECTIVE

The purpose of this study was to demonstrate that the use of adjuvant chemotherapy in patients with T3N0 adenocarcinoma with inadequate lymph node harvest is beneficial.

DESIGN

This was a retrospective population-based study of patients with resected T3N0 adenocarcinoma of the colon.

SETTINGS

The National Cancer Database was queried from 2003 to 2012.

PATIENTS

A total of 134,567 patients with T3N0 colon cancer were included in this analysis.

MAIN OUTCOME MEASURES

The use of chemotherapy, short-term outcomes, and overall survival was evaluated. Clinicopathologic factors associated with omission of chemotherapy were also analyzed.

RESULTS

Inadequate lymph node harvest was observed in 23.3% of patients, and this rate decreased over the study period from 46.8% in 2003 to 12.5% in 2012 (p < 0.0001). Overall 5-year survival for patients with T3N0 cancer was 66.8%. Inadequate lymph node harvest among these patients was associated with lower overall 5-year survival (58.7% vs 69.8%; p < 0.001). The use of adjuvant chemotherapy among patients with T3N0 cancer after inadequate lymph node harvest was only 16.7%. In a multivariable analysis, factors associated with failure to receive chemotherapy included advanced age (OR = 0.44 (95% CI, 0.43-0.45)), increased comorbidities (OR = 0.7 (95% CI, 0.66-0.76)), and postoperative readmission (OR = 0.78 (95% CI, 0.67-0.91)). Patients with inadequate lymph node harvest who received adjuvant chemotherapy had improved 5-year survival (chemotherapy, 78.4% vs no chemotherapy, 54.7%; p < 0.001). Even when controlling for all of the significant variables, the administration of chemotherapy remained a predictor of decreased mortality (HR = 0.57 (95% CI, 0.54-0.60); p < 0.001).

LIMITATIONS

This study was limited by its retrospective, population-based design.

CONCLUSIONS

Patients with T3N0 colon cancer with inadequate lymph node harvest who receive adjuvant chemotherapy have increased overall survival. Despite this survival benefit, a fraction of these patients receive adjuvant chemotherapy. Barriers to chemotherapy are multifactorial.

Prognostic Utility of Immunoprofiling in Colon Cancer: Results from a Prospective, Multicenter Nodal Ultrastaging Trial

BACKGROUND

Retrospective data indicate that immunoprofiling of T cell markers can be prognostic in colon cancer. Prospective T cell immunoprofiling of colon cancer has not been well defined for patients whose lymph nodes are ultrastaged.

STUDY DESIGN

A prospective cohort was selected from patients enrolled in an ongoing phase II multicenter trial of nodal ultrastaging for colon cancer. Primary tumor specimens from 89 patients were analyzed by immunohistochemistry for the T cells CD3(+), CD4(+), CD8(+), and FOXP3(+). Lymphocyte populations were quantified with digital image analysis. Results were examined for their association with 5-year disease-free survival along with TNM stage and clinicopathologic variables.

RESULTS

Longer disease-free survival was associated with higher CD3(+) counts at the invasive margin (IM) (p = 0.005), higher CD8(+) counts at the tumor center (TC) and IM (p = 0.002), a lower CD4(+)/CD8(+) ratio at the TC+IM (p = 0.027), and a higher CD8(+)/FOXP3(+) ratio at the TC+IM (p = 0.020). After multivariable analysis, CD8(+) at the TC+IM (p = 0.002), the CD8(+)/FOXP3(+) ratio at the TC+IM (p = 0.004), and the number of tumor-positive lymph nodes (p = 0.003) remained significant.

CONCLUSIONS

This is the first prospective demonstration of the prognostic utility of immunoprofiling in colon cancer after nodal ultrastaging. Staging based on tumor immunoprofile can augment TNM staging and provide targets for specific immunotherapies.

Nanotechnology and Pediatric Cancer: Prevention, Diagnosis and Treatment

Despite development of new approaches for the treatment of cancer disease, it is the second cause of mortality in world. Annually, 30000 persons die in Iran due to cancer diseases. Eighty percent of cancer patients are children which about 50% children lead to death. Given the high rate of cancer-related death, the new approaches for prevention, control, early diagnosis, and treatment of this disease seem necessary. Investigation of new strategies is the major challenge for scientists at recent century. Nanotechnology as a new scientific field with novel and small compounds utilized different fields over the past ten years especially in medicine. This science has come to the forefront in the areas of medical diagnostics, imaging, and therapeutic scheduls. Therefore, it has the potential applications for cancer detection and therapy. This review will discuss the therapeutic applications of different nano-materials in diagnosis, imaging, and delivery of therapeutic agents for the treatment of cancer with a major focus on their applications for the treatment of cancer and cancer- related diseases in children. The advancements in established nanoparticle technologies such as liposomes, polymer micelles, and functionalization regarding tumor targeting and controlled release strategies as well as drug delivery were discussed. It will also review the blood toxicity of used nanostructures.