Newer Pathologic Assessment Techniques for Colorectal Carcinoma

Paratesticular metastasis from colorectal adenocarcinoma presenting as hydrocele: a rare case report and literature review

Colorectal cancer, with the liver being the most common site of distant metastasis, followed by the lungs and bones. Although reports of metastasis to the testis exist, paratesticular metastasis is extremely rare. A 37-year-old male presented with scrotal swelling. Ultrasound revealed hydrocele of the tunica vaginalis. The patient underwent routine surgical treatment, and postoperative pathology of the tunica vaginalis indicated adenocarcinoma of gastrointestinal origin. Colonoscopic biopsy confirmed adenocarcinoma of the sigmoid colon. After six months of systemic therapy, tumor reduction surgery was performed in conjunction with tunica vaginalis excision. Postoperative pathology suggested histological similarity in both sites, with immunohistochemistry results supporting the diagnosis of sigmoid colon adenocarcinoma metastasizing to the tunica vaginalis. We conducted a literature review, summarizing and discussing clinical presentations, metastatic pathways, and diagnostic approaches.

Prognostic impact of stromal periostin expression in upper urinary tract urothelial carcinoma

Background

Periostin is an extracellular matrix protein that has been known to be implicated in fibrillogenesis and cell migration, including cancer metastasis. Periostin overexpression in cancer cells and/or intervening stroma is usually related to tumor progression and poor patient outcomes in various human cancers; however, its role in urothelial carcinoma, especially upper urinary tract urothelial carcinomas (UTUCs), remains inconclusive.

Methods

Samples from 126 consecutive cases of invasive UTUC (69 renal pelvic cancers and 57 ureteral cancers) were histologically reviewed and analyzed for periostin expression using immunohistochemistry. The intensities of immunoreactivity and the fraction of positive cancer cells and stroma (i.e., epithelial and stromal expression, respectively) were classified into four categories each (intensity, 0–3; fraction, 0–25% = 1; 26–50% = 2; 51–75% = 3; and > 75% = 4). The overall score was determined by multiplying both scores, and overall scores ≥ 6 were considered to indicate high periostin expression.

Results

Among 126 UTUCs, 55 (44%; 27 renal pelvic and 28 ureteral cancers) showed high stromal periostin expression. None of the cases were considered to have high epithelial periostin expression. High stromal periostin expression was associated with non-papillary gross findings, higher pathological T category, lymphovascular invasion, concomitant carcinoma in situ, subtype histology, lymph node metastasis, positive surgical margins, high tumor budding, and high tumor-associated immune cell status. Multivariate analysis revealed that high stromal periostin expression was an independent predictor of overall survival (p = 0.00072, hazard ratio = 3.62), and lymphovascular invasion and high stromal periostin expression were independent predictors of cancer-specific survival (p = 0.032 and 0.020, hazard ratio = 2.61 and 3.07, respectively).

Conclusions

Stromal periostin expression was often observed in invasive UTUCs with adverse clinicopathological factors and may be a useful predictor of patient outcomes.

Quality matters: International standards for biobanking

Human biospecimens provide the basis for research, leading to a better understanding of human disease biology and discovery of new treatments that are tailored to individual patients with cancer or other common complex diseases. The collection, processing, preservation, storage and providing access to these resources are key activities of biobanks. Biobanks must ensure proper quality of samples and data, ethical and legal compliance as well as transparent and efficient access procedures. The standards for biobanking outlined herein are intended to be implemented in biobanks and to supply researchers with high‐quality samples fitted for an intended use.

Prognostic impact of tumor budding and EMT in periampullary adenocarcinoma: a quantitative approach

The presence of invasive cell clusters known as tumor budding and the closely related epithelial mesenchymal transition (EMT) have a prognostic impact on cancer patients' overall survival. Interestingly, data quantitatively analyzing and correlating the amount of tumor buds and patient overall survival as well as the impact of expression of epithelial phenotype markers are missing. Periampullary carcinoma samples of 171 patients were immunohistochemically stained for E-Cadherin (ECad). Tumor cell clusters (TCC, defined from one to 50 cells) were manually quantified comprising tumor cell number and subcellular localization of ECad expression (membranous, cytoplasmic or mixed). Data analyses were performed using elastic net feature selection. Hereby, five distinct intervals of TCC sizes and corresponding fractions of cells with distinct ECad expression were identified. Prognostic features of the defined budding categories were entered into a subsequent Cox regression model together with standard clinicopathological parameters and, based on the model prediction, cases were categorized into "low and high budding" grades. Overall median TCC size was 16 cells (range: 2-36 cells). The median number of TCCs per tumor was 42 (range: 3-283). Elastic net feature selection identified TCCs of 6-10 and 31-35 cells as prognostically most relevant negative and positive features, respectively. Regarding ECad expression, cytoplasmic ECad expression in TCCs of 11-15 as well as of 26-30 cells revealed prognostic relevance. Combining TCC numbers and ECad expression, budding grade qualified as independent prognostic factor for patient overall survival (p<0.001) in a multivariable clinicopathologic Cox model. Applying an advanced modelling by machine learning on a cohort of periampullary cancers, we show that not the smallest TCCs (1-5 cells) but tumor cell nests containing 6-10 cells display the strongest negative prognostic relevance. Moreover, we demonstrate that larger TCCs might have a strong positive prognostic impact in periampullary adenocarcinomas, contributing to establishing an advanced grading system.

Differential Immune Reactivity Pattern of SW48 and SW1116 Colorectal Cancer Cell Lines with Colorectal Cancer Patients Sera

BACKGROUND

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. It is also known as the second leading cause of deaths as the early stage detection is not yet available by current methods. So identification of biomarkers can also be functional in early diagnosis and prognosis.

MATERIALS AND METHODS

We examined sera from 60 CRC patients of different stages as a source of auto-antibody as well as two human CRC cell lines with different invasive capacities (SW48 and SW1116) as the source of antigens. The pattern of immune reactivity in immuneblotting tests between mentioned cell lines and CRC patients' sera were evaluated by ImageJ software.

RESULTS

The Immune reactivity pattern of two cell lines (SW48 and SW1116) with CRC patients' sera were different in band intensities and the most immune reactivity intensity was observed in SW48 cell lysate with sera from Stage III CRC patients.

CONCLUSION

Due to the humoral immune response, sera from Stage III CRC patients contained autoantibodies that demonstrated higher immune reactivity. Moreover, SW48 cell line with high aggressive behavior reacted to CRC patients' sera with greater intensity compared with less aggressive behavior cell line (SW1116). Therefore, it is required to use other techniques such as two-dimensional electrophoresis and mass spectrometry.

High-Grade Tumor Budding Stratifies Early-Stage Cervical Cancer with Recurrence Risk

OBJECTIVES

This study investigated prognostic significance of tumor budding in early-stage cervical cancer (ESCC) following radical surgery and its contribution to improve the stratification of patients with recurrence risk.

METHODS

The archival medical records and H&E-stained slides of 643 patients with IA2-IIA stage cervical cancer who underwent radical surgery were retrospectively reviewed. Clinicopathological parameters were noted, and tumor buds were counted using immunohistochemistry for each case. The prognostic significance of tumor budding was analyzed. Prediction models that comprised tumor budding were established, and the performance was compared between the novel models and classic criteria via log-rank test and receiver operating characteristic analysis.

RESULTS

Tumors with high-grade tumor budding (HTB) exhibited a substantially increased risk of recurrence (hazard ratio = 4.287, P < 0.001). Nine predictive models for recurrence were established, in which HTB was combined with recognized risk factors. The model using of at least two risk factors of HTB, tumor size ≥ 4 cm, deep stromal invasion of outer 1/3, and lymphovascular space invasion to stratify patients with an intermediate risk was most predictive of recurrence compared with the classic criteria.

CONCLUSIONS

Tumor budding is an independent, unfavorable, prognostic factor for ESCC patients following radical surgery and holds promise for improved recurrence risk stratification.

Diagnostic reproducibility of tumour budding in colorectal cancer: a multicentre, multinational study using virtual microscopy

AIMS

Despite the established prognostic relevance of tumour budding in colorectal cancer, the reproducibility of the methods reported for its assessment has not yet been determined, limiting its use and reporting in routine pathology practice.

METHODS AND RESULTS

A morphometric system within telepathology was devised to evaluate the reproducibility of the various methods published for the assessment of tumour budding in colorectal cancer. Five methods were selected to evaluate the diagnostic reproducibility among 10 investigators, using haematoxylin and eosin (H&E) and AE1-3 cytokeratin-immunostained, whole-slide digital scans from 50 pT1-pT4 colorectal cancers. The overall interobserver agreement was fair for all methods, and increased to moderate for pT1 cancers. The intraobserver agreement was also fair for all methods and moderate for pT1 cancers. Agreement was dependent on the participants' experience with tumour budding reporting and performance time. Cytokeratin immunohistochemistry detected a higher percentage of tumour budding-positive cases with all methods compared to H&E-stained slides, but did not influence agreement levels.

CONCLUSION

An overall fair level of diagnostic agreement for tumour budding in colorectal cancer was demonstrated, which was significantly higher in early cancer and among experienced gastrointestinal pathologists. Cytokeratin immunostaining facilitated detection of budding cancer cells, but did not result in improved interobserver agreement.

Prognostic significance of CD168 overexpression in colorectal cancer

The expression of cluster of differentiation 168 (CD168), a cell surface receptor for hyaluronan, is associated with cancer progression and metastases. The aim of the present study was to analyze the expression of CD168 by immunohistochemistry in colorectal cancer (CRC) and to examine the association between CD168 expression and clinicopathological features, including survival. A total of 78 tissue specimens obtained from consecutive CRC patients exhibiting various tumor node metastasis (TNM) stages were immunostained for the analysis of CD168 expression. The prognostic value of CD168 was subsequently evaluated. Kaplan-Meier survival analysis revealed that CD168 overexpression was significantly associated with overall survival (P<0.05); however, no significant association was identified between CD168 expression and tumor location, tumor differentiation or TNM stage. Overexpression of CD168 was closely associated with poorer patient survival, which indicates that it may present a useful indicator for clinical prognosis.

MTHFR C677T polymorphism and anatomopathological characteristics with prognostic significance in sporadic colorectal cancer

Methylenetetrahydrofolate reductase (MTHFR) plays a key role in folate metabolism, and folate is implicated in carcinogenesis due to its role in DNA methylation, repair and synthesis. The MTHFR C677T polymorphism is associated with decreased risk of CRC and increased sensitivity to 5-FU treatment. The present study addressed the relationship between this polymorphism and histopathological and immunohistochemical characteristics of prognostic significance in 50 patients from the Canary Islands. No differences were found between the MTHFR C677T genotypes with respect to tumor budding, tumor necrosis, desmoplastic fibrosis and tumoral eosinophilia. No significant differences were found in Ki-67, bcl-2 (cytoplasmic and nuclear), CD31, CD3+ T lymphocytes (both stromal and intraepithelial) and peritumoral CD20+ B lymphocytes. In carriers of the MTHFR CC variant, tumor margins were infiltrative more frequently (68.7%) than in CT+TT carriers (33.3%, p=0.03). In addition, wild-type CC genotype showed stromal CD20+ B lymphocytes (68.8%) more often than CT+TT carriers (33.3%, p=0.03). Both parameters indicate a better tumor prognosis when the MTHFR 677T variant is present.

Tumour border configuration in colorectal cancer: proposal for an alternative scoring system based on the percentage of infiltrating margin

AIMS

Information on tumour border configuration (TBC) in colorectal cancer (CRC) is currently not included in most pathology reports, owing to lack of reproducibility and/or established evaluation systems. The aim of this study was to investigate whether an alternative scoring system based on the percentage of the infiltrating component may represent a reliable method for assessing TBC.

METHODS AND RESULTS

Two hundred and fifteen CRCs with complete clinicopathological data were evaluated by two independent observers, both 'traditionally' by assigning the tumours into pushing/infiltrating/mixed categories, and alternatively by scoring the percentage of infiltrating margin. With the pushing/infiltrating/mixed pattern method, interobserver agreement (IOA) was moderate (κ = 0.58), whereas with the percentage of infiltrating margins method, IOA was excellent (intraclass correlation coefficient of 0.86). A higher percentage of infiltrating margin correlated with adverse features such as higher grade (P = 0.0025), higher pT (P = 0.0007), pN (P = 0.0001) and pM classification (P = 0.0063), high-grade tumour budding (P < 0.0001), lymphatic invasion (P < 0.0001), vascular invasion (P = 0.0032), and shorter survival (P = 0.0008), and was significantly associated with an increased probability of lymph node metastasis (P < 0.001).

CONCLUSIONS

Information on TBC gives additional prognostic value to pathology reports on CRC. The novel proposed scoring system, by using the percentage of infiltrating margin, outperforms the 'traditional' way of reporting TBC. Additionally, it is reproducible and simple to apply, and can therefore be easily integrated into daily diagnostic practice.

Pathologic processing of the total mesorectal excision

Total mesorectal excision (TME) is the current optimal surgical treatment for patients with rectal carcinoma. A complete TME is related to lower local recurrence rates and increased patient survival. Many confounding factors in the patient's anatomy and prior therapy can make it difficult to obtain a perfect plane, and thus a complete TME. The resection specimen can be thoroughly evaluated, grossly and microscopically, to identify substandard surgical outcomes and increased risk of local recurrence. Complete and accurate data reporting is critical for patient care and helps surgeons improve their technique.

Tumor budding is an independent prognostic factor for prediction of lymph node metastasis in oral squamous cell carcinoma

OBJECTIVE

Despite the enormous advances in diagnostic and management modalities of oral squamous cell carcinoma (OSCC), the mortality rates have remained stagnant with a 5-year survival rate of <50% challenging the available methods of prognostic assessment. Presence of tumor budding has been associated with aggressive behavior and is correlated with lymph node metastasis, recurrence, distant metastasis, and decreased survival in several cancers. However, the prognostic significance of this apparently simple to evaluate parameter is sparse in OSCC.

METHODS

A total of 75 cases of surgically excised OSCC were analyzed for tumor budding along with other clinicopathologic parameters. Tumor budding was graded as high and low intensity based on presence and absence of ≥10 or <10 budding foci in hematoxylin and eosin-stained sections. An association between the clinicopathological parameters, lymph node metastases with the budding index was examined using univariate and multivariate analyses.

RESULTS

Tumor budding was evident in 89% of cases with around 45.3% of the cases demonstrated high-intensity budding. High-intensity tumor budding was significantly associated with lymph node metastasis and depth of invasion. Multivariate analysis demonstrated that tumor budding and depth of invasion were significant independent predictors for lymph node metastasis.

CONCLUSION

Tumor budding is frequently encountered histologic marker in OSCC. High-intensity tumor budding is a strong independent prognostic factor for prediction of lymph node metastasis.

Prognostic value of poorly differentiated clusters in invasive breast cancer

BACKGROUND

Our study aimed to assess the prognostic value of poorly differentiated clusters (PDCs) in invasive breast cancer.

METHODS

A total of 146 cases of operable invasive ductal carcinoma that was not otherwise specified (IDC-NOS), from 2002 to 2009, were pathologically reviewed. Cancer clusters with five or more cancer cells and lacking gland-like structures were counted from a field containing maximum clusters in H & E slides under a×20 objective lens (0.950 mm2 field of vision).

RESULTS

Tumors with <5, 5 to 9, and ≥10 clusters were graded as G1, G2, and G3, respectively (n=41, 60, and 45 tumors, respectively). An interobserver test showed good reproducibility, with a Cohen's kappa coefficient of 0.739. The PDC grade was significantly associated with N stage (P<0.001), lymphovascular invasion (P=0.007), tumor budding grade (P<0.001), relapse rate (P<0.001), and death rate (P<0.001). Survival analyses revealed that the PDC grade was a significant prognostic factor for disease-free survival (hazard ratio 3.811; P<0.001) and overall survival (hazard ratio 3.730; P=0.001), independent of T stage, N stage, or tumor budding grade.

CONCLUSIONS

The PDC grade is an independent prognostic factor of IDC-NOS. Considering the simplicity and availability of this method relative to conventional clinical pathology, PDCs may serve as a novel prognostic histological characteristic in IDC-NOS.

Need for objective and reproducible criteria in histopathological assessment of total mesorectal excision specimens: lessons from a national improvement project

AIM

Data on quality control of the pathologic evaluation of total mesorectal excision (TME) specimens are scarce. We aimed to assess differences between evaluation by local pathologists participating in PROject on CAncer of the REctum (PROCARE; a Belgian improvement project on rectal cancer) and by a review panel of experts.

METHOD

Based on photographic material and histopathology slides, a Review Committee of gastrointestinal expert pathologists re-evaluated the mesorectal plane, the tumour differentiation grade, the (y)pT stage and the tumour regression grade in 444 patients previously routinely assessed by local pathologists.

RESULTS

The surgical plane was reported in 89% of patients and the circumferential resection margin in 88% of patients by the local pathologist. The median number of lymph nodes harvested in patients undergoing neoadjuvant radiochemotherapy was 11 and 14 in the other patients. The Review Committee downgraded the surgical plane from (intra)mesorectal to intramuscular in 17% of patients, and upgraded it from intramuscular to (intra)mesorectal in 27%. Tumour differentiation grade, T stage and tumour regression grade differed between local pathologists and the Review Committee in 15%, 10% and 38%, respectively, of patients. T stage was upgraded, mainly from T2 to T3, in 8% of patients. Tumour regression was judged by the Review Committee to be less advanced in 15% of patients.

CONCLUSION

Acknowledging some shortcomings, this study gives a realistic view of clinical practice. There are differences in interpretation with regard to both macroscopic and microscopic analysis of TME specimens. These findings indicate a need for more objective and reproducible criteria in histopathology. Being aware of this is a first step for improvement.

Prognostic and predictive value of circulating tumor cell analysis in colorectal cancer patients

Objective

The aim of this study was to assess the prognostic and predictive values of circulating tumor cell (CTC) analysis in colorectal cancer patients.

Patients and methods

Presence of CTCs was evaluated in 60 colorectal cancer patients before systemic therapy - from which 33 patients were also evaluable for CTC analysis during the first 3 months of treatment - through immunomagnetic enrichment, using the antibodies BM7 and VU1D9 (targeting mucin 1 and EpCAM, respectively), followed by real-time RT-PCR analysis of the tumor-associated genes KRT19, MUC1, EPCAM, CEACAM5 and BIRC5.

Results

Patients were stratified into groups according to CTC detection (CTC negative, when all marker genes were negative; and CTC positive when at least one of the marker genes was positive). Patients with CTC positivity at baseline had a significant shorter median progression-free survival (median PFS 181.0 days; 95% CI 146.9-215.1) compared with patients with no CTCs (median PFS 329.0 days; 95% CI 299.6-358.4; Log-rank P < .0001). Moreover, a statistically significant correlation was also founded between CTC detection during treatment and radiographic findings at the 6 month staging. This correlation applied to CTC results before therapy (odds ratio (OR), 6.22), 1 to 4 weeks after beginning of treatment (OR, 5.50), 5 to 8 weeks after beginning of treatment (OR, 7.94) 9 to 12 weeks after beginning of treatment (OR, 14.00) and overall CTC fluctuation during the course of treatment (OR, 20.57).

Conclusion

The present study provides evidence of a strong correlation between CTC detection and radiographic disease progression in patients receiving chemotherapy for colorectal cancer. Our results suggest that in addition to the current prognostic factors, CTC analysis represent a potential complementary tool for prediction of colorectal cancer patients’ outcome. Moreover, the present test allows for molecular characterization of CTCs, which may be of relevance to the creation of personalized therapies.

Tumor budding in colorectal carcinoma: time to take notice

Tumor 'budding', loosely defined by the presence of individual cells and small clusters of tumor cells at the invasive front of carcinomas, has received much recent attention, particularly in the setting of colorectal carcinoma. It has been postulated to represent an epithelial-mesenchymal transition. Tumor budding is a well-established independent adverse prognostic factor in colorectal carcinoma that may allow for stratification of patients into risk categories more meaningful than those defined by TNM staging, and also potentially guide treatment decisions, especially in T1 and T3 N0 (Stage II, Dukes' B) colorectal carcinoma. Unfortunately, its universal acceptance as a reportable factor has been held back by a lack of definitional uniformity with respect to both qualitative and quantitative aspects of tumor budding. The purpose of this review is fourfold: (1) to describe the morphology of tumor budding and its relationship to other potentially important features of the invasive front; (2) to summarize current knowledge regarding the prognostic significance and potential clinical implications of this histomorphological feature; (3) to highlight the challenges posed by a lack of data to allow standardization with respect to the qualitative and quantitative criteria used to define budding; and (4) to present a practical approach to the assessment of tumor budding in everyday practice.

The impact of CpG island methylator phenotype and microsatellite instability on tumour budding in colorectal cancer

AIMS

In colorectal cancer, tumour budding, a process likened to epithelial mesenchymal transition, is an adverse prognostic factor which is rarely found in tumours with high-level microsatellite instability (MSI-H). Cases with MSI-H or high-level CpG island methylator phenotype (CIMP-H) have similar histomorphological features, yet seemingly opposite prognosis. We hypothesized that tumour budding is related to CIMP, thus partially explaining this prognostic difference.

METHODS AND RESULTS

MSI, KRAS, BRAF, CIMP and 0(6)-methylguanine-DNA methyltransferase (MGMT) were investigated in tissues from 127 colorectal cancer patients. Tumour budding was scored using pan-cytokeratin-stained whole tissue sections within the densest area of buds (×40). Tumour budding was not associated with KRAS, BRAF, MGMT or CIMP, but was correlated inversely with MSI-H (P = 0.0049). Multivariate survival time analysis revealed that tumour budding was independent of all five molecular features and was predicted by MSI status [odds ratio (OR): 4.29, 95% confidence interval (CI) 1.5-12.1; P = 0.006)], but not CIMP (OR: 0.81, 95% CI 0.3-2.5; P = 0.714).

CONCLUSIONS

These findings underline that MSI, rather than CIMP, plays a role in conferring a tumour budding phenotype. Budding retains its unfavourable prognostic effect independently of these five molecular features. Continued efforts to standardize the assessment of tumour budding are necessary to integrate this feature into daily diagnostic routine.

New criteria for histologic grading of colorectal cancer

Conventional tumor grading systems based on the degree of tumor differentiation may not always be optimal because of difficulty in objective assessment and insufficient prognostic value for decision making in colorectal cancer (CRC) treatment. This study aimed to determine the importance of assessing the number of poorly differentiated clusters as the primary criterion for histologic grading of CRC. Five hundred consecutive patients with curatively resected stage II and III CRCs (2000 to 2005) were pathologically reviewed. Cancer clusters of ≥5 cancer cells and lacking a gland-like structure were counted under a ×20 objective lens in a field containing the highest number of clusters. Tumors with <5, 5 to 9, and ≥10 clusters were classified as grade (G)1, G2, and G3, respectively (n=156, 198, and 146 tumors, respectively). Five-year disease-free survival rates were 96%, 85%, and 59% for G1, G2, and G3, respectively (P<0.0001). Poorly differentiated clusters affected survival outcome independent of T and N stages and could help in more effective stratification of patients by survival outcome compared with tumor staging (Akaike information criterion, 1086.7 vs. 1117.0; Harrell concordance index, 0.73 vs. 0.67). The poorly differentiated cluster-based grading system showed a higher weighted κ coefficient for interobserver variability (5 observers) compared with conventional grading systems (mean, 0.66 vs. 0.52; range, 0.55 to 0.73 vs. 0.39 to 0.68). Our novel histologic grading system is expected to be less subjective and more informative for prognostic prediction compared with conventional tumor grading systems and TNM staging. It could be valuable in determining individualized postoperative CRC treatment.

Morphology and prognostic value of tumor budding in rectal cancer after neoadjuvant radiotherapy

Tumor budding is an acknowledged prognostic marker in colorectal cancer. This study was conducted to investigate the morphology and prognostic significance of budding in rectal cancer after neoadjuvant radiotherapy. Surgical specimens from 96 consecutive patients who underwent neoadjuvant radiotherapy and curative resection were retrieved to assess budding and other clinicopathologic factors. The morphology and prognostic significance of postirradiation tumor budding were closely associated with tumor regression grade. In the tumor regression grade 1 group, tumor budding presented as "false budding" and did not have a significant association with prognosis. In the tumor regression grade 2 and 3 groups, budding was observed surrounded by radiation-induced fibrosis and large populations of infiltrating inflammatory cells, and budding intensity was significantly associated with histologic differentiation, ypN stage, and lymphovascular invasion (P < .05). Moreover, the low-grade budding subgroup showed a significantly higher rate of 5-year disease-free survival than the high-grade budding subgroup (87.5% versus 55.6%, P < .0001). Multivariate analysis showed that pretreatment serum carcinoembyronic antigen, tumor regression grade, and tumor budding were the major independent factors affecting long-term disease-free survival. In conclusion, postirradiation budding has distinct morphology and prognostic significance in rectal cancer after neoadjuvant radiotherapy.

Perspectives on current tumor-node-metastasis (TNM) staging of cancers of the colon and rectum

Improvements in classifications of cancers based on discovery and validation of important histopathological parameters and new molecular markers continue unabated. Though still not perfect, recent updates of classification schemes in gastrointestinal oncology by the American Joint Commission on Cancer (tumor-node-metastasis [TNM] staging) and the World Health Organization further stratify patients and guide optimization of treatment strategies and better predict patient outcomes. These updates recognize the heterogeneity of patient populations with significant subgrouping of each tumor stage and use of tumor deposits to significantly "up-stage" some cancers; change staging parameters for subsets of IIIB and IIIC cancers; and introduce of several new subtypes of colon carcinomas. By the nature of the process, recent discoveries that are important to improving even routine standards of patient care, especially new advances in molecular medicine, are not incorporated into these systems. Nonetheless, these classifications significantly advance clinical standards and are welcome enhancements to our current methods of cancer reporting.

Lymph node yield following injection of patent blue V dye into colorectal cancer specimens

AIM

The study aimed to assess whether the ex vivo injection of patent blue V dye would increase lymph node yield in operative specimens of colorectal cancer.

METHOD

A randomized controlled trial was carried out in which patients undergoing resection for colonic cancer were allocated to patent V blue or no patent blue V dye submucosal injection of the operative specimen. The number of lymph nodes found in each group was compared.

RESULTS

Between 1 January and 31 December 2008, 68 patients were randomized. Thirty-three patients received patent blue V dye and 34 did not. In the former group the median number of blue nodes identified was 11, compared with a median of 9 in the no dye group. After the application of Carnoy's solution lymph node count was 16 in each group. There was no significant difference between all these results.

CONCLUSION

Ex vivo injection of patent blue V dye submucosally in a peritumour location did not increase the lymph node count or the percentage of specimens having more than 12 lymph nodes identified.

Epithelial mesenchymal transition and tumor budding in aggressive colorectal cancer: tumor budding as oncotarget

Epithelial mesenchymal transition (EMT) is proposed as a critical mechanism for the acquisition of malignant phenotypes by epithelial cells. In colorectal cancer, tumor cells having undergone EMT are histologically represented by the presence of tumor buds defined as single cells or small clusters of de-differentiated tumor cells at the invasive front. Tumor budding is not a static, histological feature rather it represents a snap-shot of a dynamic process undertaken by an aggressive tumor with the potential to disseminate and metastasize. Strong, consistent evidence shows that tumor budding is a predictor of lymph node metastasis, distant metastatic disease, local recurrence, worse overall and disease-free survival time and an independent prognostic factor. Moreover, the International Union against Cancer (UICC) recognizes tumor budding as a highly relevant, additional prognostic parameter. The aim of this review is to summarize the evidence supporting the implementation of tumor budding into diagnostic pathology and patient management and additionally to illustrate its worthiness as a potential therapeutic target.

Lymph node micrometastases and isolated tumor cells influence survival in stage I and II colon cancer

PURPOSE

Lymph-node status is considered the most important prognostic factor in colorectal cancer. The aim of the present prospective study was to evaluate the influence of micrometastases and isolated tumor cells on recurrence and disease-free survival in colon cancer.

METHODS

A total of 193 patients with colon cancer, operated on between 2000 and 2005, were enrolled in the study. All lymph nodes were examined by routine microscopy in hematoxylin and eosin-stained sections. If no metastases were identified in any node, all nodes were examined immunohistochemically with monoclonal antibody CAM 5.2.

RESULTS

Ordinary metastases were found in 67 patients, leaving 126 patients in stage I/II. Immunohistochemistry showed that 5% (6/126) of these had micrometastases and 26% (33/126) had isolated tumor cells. A median of 5 years of follow-up revealed local or distant recurrence in 23% (9/39) of stage I/II patients with micrometastases or isolated tumor cells, compared with 7% (6/87) without micrometastases or isolated tumor cells (P = .010). Five-year disease-free survival for patients with and without micrometastases or isolated tumor cells was 75% and 93%, respectively (P = .012). When analyzed separately, patients with isolated tumor cells (excluding micrometastases) had also lower survival than node-negative patients (P = .012).

CONCLUSION

The presence of micrometastases and isolated tumor cells was found to be a prognostic factor for recurrence and disease-free survival. This may have implications for future treatment of stage I/II colon cancer.

TNM staging system of colorectal carcinoma: a critical appraisal of challenging issues

CONTEXT

Colorectal cancer is the leading cause of morbidity and death among gastrointestinal tumors and ranks fourth after lung, breast, and ovarian cancers. Despite a continuous refinement of the T (tumor), N (node), and M (metastasis) staging system to express disease extent and define prognosis, and eventually to guide treatment, the outcome of patients with colorectal cancer may vary considerably even within the same tumor stage. Therefore, the need for new factors, either morphologic or molecular, that could more precisely stratify patients into different risk categories is clearly warranted.

OBJECTIVES

To present the state of the art with regard to the colorectal cancer staging system and to discuss confusing and/or challenging issues, including the assessment of peritoneal membrane involvement, vascular invasion, tumor deposits, and pathologic tumor response to neoadjuvant chemoradiotherapy.

DATA SOURCES

Literature review of relevant articles indexed in PubMed (US National Library of Medicine) and primary material from the authors' institutions.

CONCLUSIONS

Two emerging needs exist for the TNM system, namely, further stratification of patients with the same tumor stage and incorporation of nonanatomic factors, the latter including molecular and treatment factors. The identification and classification of morphologic features encountered in the pathologic examination of colorectal cancer specimens may be difficult and a source of subjective variability. Enhanced pathologic analysis, agreed-upon standard protocols, and standardization should improve the completeness and accuracy of pathology reports.

Multi-institutional study of risk factors of liver metastasis from colorectal cancer: correlation with CD10 expression

BACKGROUND

The risk factors for liver metastasis from colorectal cancer are still unclear. We therefore evaluated the relationships between various clinicopathological factors, including CD10 expression, liver metastasis, and survival, in patients with colorectal cancer.

METHODS

Clinicopathological data for 1,025 patients with stage II or III colorectal cancer who underwent curative surgery in four participating hospitals were collected and evaluated. Three pathologists examined focal dedifferentiation, venous invasion, and CD10 expression without knowledge of the clinical outcome.

RESULTS

Univariate analysis showed that pathological T (pT), pathological N (pN), venous invasion, focal dedifferentiation, and CD10 expression were significantly associated with liver metastasis. Multivariate analysis selected pT, pN, and CD10 expression as significant risk factors for liver metastasis. pT, pN and CD10 were also shown by univariate and multivariate analyses to be significantly associated with disease-free survival. The incidence of liver metastasis was 3% in pN0 patients with CD10-negative or pT2 or pT3 tumors and 28% in pN2 patients with CD10-positive or pT4 tumors.

CONCLUSIONS

CD10 expression is a significant risk factor for liver metastasis in patients with colorectal cancer and is correlated with prognosis. Patients with a high risk of liver metastasis can be selected on the basis of pT, pN, and CD10 expression.

KRAS mutation screening in colorectal cancer: From paper to practice

The identification of KRAS mutation status as a predictive biomarker for the activity of epidermal growth factor receptor (EGFR) inhibitors in metastatic colorectal cancer has marked a turning point in the use of these agents in the clinic. A wealth of data indicates that patients with wild-type KRAS derive meaningful clinical benefit from cetuximab in first- and second-line settings and beyond, both in combination and as a single agent, and from panitumumab as a single agent in the refractory setting. Patients with KRAS-mutant tumors do not benefit from EGFR inhibition and should not be treated with these agents. KRAS mutation testing should be part of routine standard practice, preferably at the time of diagnosis or early in the course of management. Immediate knowledge of the KRAS mutation status of a tumor allows for the optimal incorporation of anti-EGFR monoclonal antibody (MoAb) therapy where it may be most beneficial for the patient, such as in downstaging regimens outside of the refractory setting where anti-EGFR MoAb therapy is otherwise typically indicated. Available technologies make this test relatively easy to implement; archival paraffin-embedded samples from primary or metastatic sites can be used indistinctly without compromising reliability and without the need for repeated biopsies. Several diagnostic laboratories provide KRAS testing services. This powerful selection tool reduces unnecessary toxicities and costs and should be part of the standard diagnostic workup of any patient.

Invasive front of colorectal cancer: Dynamic interface of pro-/anti-tumor factors

Tumor-host interaction at the invasive front of colorectal cancer represents a critical interface encompassing a dynamic process of de-differentiation of colorectal carcinoma cells known as epithelial mesenchymal transition (EMT). EMT can be identified histologically by the presence of “tumor budding”, a feature which can be highly specific for tumors showing an infiltrating tumor growth pattern. Importantly, tumor budding and tumor border configuration have generated considerable interest as additional prognostic factors and are also recognized as such by the International Union Against Cancer. Evidence seems to suggest that the presence of tumor budding or an infiltrating growth pattern is inversely correlated with the presence of immune and inflammatory responses at the invasive tumor front. In fact, several tumor-associated antigens such as CD3, CD4, CD8, CD20, Granzyme B, FOXP3 and other immunological or inflammatory cell types have been identified as potentially prognostic in patients with this disease. Evidence seems to suggest that the balance between pro-tumor (including budding and infiltrating growth pattern) and anti-tumor (immune response or certain inflammatory cell types) factors at the invasive front of colorectal cancer may be decisive in determining tumor progression and the clinical outcome of patients with colorectal cancer. On one hand, the infiltrating tumor border configuration and tumor budding promote progression and dissemination of tumor cells by penetrating the vascular and lymphatic vessels. On the other, the host attempts to fend off this attack by mounting an immune response to protect vascular and lymphatic channels from invasion by tumor buds. Whereas standard pathology reporting of breast and prostate cancer involves additional prognostic features, such as the BRE and Gleason scores, the ratio of pro- and anti-tumor factors could be a promising approach for the future development of a prognostic score for patients with colorectal cancer which could complement tumor node metastasis staging to improve the clinical management of patients with this disease.

Endoscopy, morphology, morphometry and molecular markers: predicting cancer risk in colorectal adenoma

The evaluation of short- and long-term risk for developing cancer in patients with colorectal adenomas is controversial. Good, reliable predictors of cancer risk in any adenoma are currently lacking and are limited to adenoma size, number and histologic type. In fact, the evaluation of any adenoma or precancer lesion (e.g., hyperplastic polyps, serrated adenoma or aberrant crypt foci) within the colorectum may be assessed by a number of techniques ranging from direct visualization through the endoscope, to microscopic assessment, and to evaluation at the molecular level. Emerging techniques may yield improved methods of adenoma risk-assessment in the near future. For one, newer endoscopy technologies include chromoendoscopy or endocytoscopy, which now render endoscopists able to resolve the surface and subsurface mucosa at cellular resolution in vivo and in real time - thus, bringing the microscope to the patient's bedside. This new era in endoscopic imaging is dubbed 'histoendoscopy'. Further, while traditional views of classifying protruding and sessile lesions include those of Haggitt, the sm-classification, the Japanese and the so-called Vienna classifications to evaluate neoplasia, the development of new molecular techniques may give way to new methods of classifying preneoplasia and precancerous lesions. This review discusses some pros and cons of risk evaluation technologies in the colorectal tract by endoscopy, microscopy, and quantitative and molecular features. The morphometry-based studies performed over the past decades for the quantitative assessment of cellular and nuclear features within adenomas have failed to yield results amenable for clinical translation and are unlikely to improve further and gain widespread use with current technology. Rather, emerging knowledge of pathway-specific markers through the outlining of a molecular classification will likely be the basis for improved detection and diagnosis. The emerging genomic and proteomic technologies allowing for noninvasive tests to detect (asymptomatic) cancer and neoplasia are discussed. Lastly, the importance of recognizing bias and pitfalls and the adherence to guidelines for biomarker research are addressed.

Previstage GCC test for staging patients with colorectal cancer

The presence of tumor cells in regional lymph nodes is the most important prognostic and predictive marker in staging patients with colorectal cancer. Cancer cells in lymph nodes are associated with a poorer prognosis and an increased risk of recurrent disease. Additionally, nodal metastases identify patients who derive maximum benefit from adjuvant therapy. However, traditional paradigms for staging patients with colorectal cancer underestimate the extent of metastases and patients whose lymph nodes are ostensibly free of tumor cells by histopathology (pN0) have a 25-30% risk of developing recurrent disease, reflected by the presence of occult nodal metastases. These observations underscore the unmet clinical need for molecular approaches to accurately detect metastatic disease and identify patients at risk for disease relapse that could benefit from adjuvant chemotherapy. Detection of disease-specific mRNA targets as prognostic and predictive markers employing quantitative reverse transcription (qRT)-PCR is an emerging technology that has become a benchmark for individualization of patient management. However, to date, applications of qRT-PCR to detecting occult nodal metastases in colorectal cancer have been equivocal, reflecting markers with suboptimal sensitivity and specificity; limitations of utilizing qualitative, rather than quantitative, RT-PCR; and underpowered study designs based on inadequate patient populations. In that context, guanylyl cyclase C (GCC) is the most sensitive and specific biomarker for metastatic colorectal cancer in extra-intestinal tissues. GCC qRT-PCR detects occult metastases in lymph nodes, providing the most powerful independent prognostic information for predicting disease recurrence in pN0 patients in prospective multicenter clinical trials. This technology forms the basis for the Previstagetrade mark GCC Colorectal Cancer Staging Test encompassing a proprietary multiplex qRT-PCR assay compatible with formalin-fixed, paraffin-embedded lymph nodes for detecting occult metastases. Previstage GCC is a new diagnostic tool that may improve the accuracy of staging, prognosis of clinical outcomes and prediction of therapeutic responses to adjuvant therapy, representing a key advance in the management of patients with colorectal cancer.

Two-marker protein profile predicts poor prognosis in patients with early rectal cancer

The aim of this study was to establish an immunohistochemical protein profile to complement preoperative staging and identify rectal cancer patients at high-risk of adverse outcome. Immunohistochemistry was performed on a tissue microarray including 482 rectal cancers for APAF-1, EphB2, MST1, Ki67, p53, RHAMM, RKIP and CD8⁺ tumour infiltrating lymphocytes (TILs). After resampling of the data and multivariable analysis, the most reproducible markers were combined and prognosis evaluated as stratified by pT and pN status. In multivariable analysis, only positive RHAMM (P<0.001; HR=1.94 (1.44–2.61)) and loss of CD8⁺ TILs (P=0.006; HR=0.63 (0.45–0.88)) were independent prognostic factors. The 5-year cancer-specific survival rate for RHAMM+/TIL− patients was 30% (95% CI 21–40%) compared to 76% (95% CI: 66–84%) for RHAMM−/TIL+ patients (P<0.001). The 5-year cancer-specific survival of T1/T2/RHAMM+/TIL− patients was 48% (20–72%) and significantly worse compared to T3/T4/RHAMM−/TIL+ patients (71% 95% CI 56–82%); P=0.039). Stratifying by nodal status, only N+/RHAMM+/TIL− patients demonstrated a significantly worse prognosis than N0/RHAMM+/TIL− patients (P=0.005). Loss of CD8⁺ TILs was predictive of local recurrence in RHAMM+ tumours (P=0.009) only. RHAMM and CD8⁺ TILs may assist in identifying early stage rectal cancer patients facing a particularly poor prognosis and who may derive a benefit from preoperative therapy.