Intensity of tumor budding and its prognostic implications in invasive colon carcinoma

Prognostic Impact of Lymphatic Invasion, Venous Invasion, Perineural Invasion, and Tumor Budding in Rectal Cancer Treated With Neoadjuvant Chemoradiotherapy Followed by Total Mesorectal Excision

BACKGROUND

The diagnostic implications of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in rectal cancer treated with neoadjuvant chemoradiotherapy are unknown.

OBJECTIVE

This study aimed to identify the prognostic impact of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy.

DESIGN

This was a retrospective cohort study.

SETTINGS

This study was conducted at the Samsung Medical Center. Grouping was performed on the basis of lymphatic invasion, venous invasion, perineural invasion, and tumor budding status: no-risk group with 0 factor (n = 299), low-risk group with any 1 factor (n = 131), intermediate-risk group with any 2 factors (n = 75), and high-risk group with 3 or 4 risk factors (n = 32).

PATIENTS

Patients who underwent neoadjuvant chemoradiotherapy, followed by radical operation for locally advanced rectal cancer, from January 2010 to December 2015 were included.

MAIN OUTCOME MEASURES

The main outcome measures were disease-free and overall survival.

RESULTS

Disease-free and overall survival varied significantly between the groups in stage III ( p < 0.001 and p < 0.001). Disease-free survival in stage I differed between the no-risk group and the intermediate-risk group ( p = 0.026). In stage II, disease-free and overall survival differed between the no-risk group and the intermediate-risk group ( p = 0.010 and p = 0.045). In multivariable analysis, risk grouping was an independent prognostic factor for both disease-free (p <0.001) and overall survival ( p < 0.001).

LIMITATIONS

The inherent limitations are associated with the retrospective single-center study design.

CONCLUSIONS

Lymphatic invasion, venous invasion, perineural invasion, and tumor budding are strong prognostic factors for disease-free and overall survival in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. Therefore, adjuvant chemotherapy is strongly recommended in patients with positive lymphatic invasion, venous invasion, perineural invasion, and tumor budding. See Video Abstract at http://links.lww.com/DCR/B919 .

IMPACTO PRONSTICO DE LA INVASIN LINFTICA, LA INVASIN VENOSA, LA INVASIN PERINEURAL Y LA GEMACIN TUMORAL EN EL CNCER DE RECTO TRATADO CON QUIMIORRADIOTERAPIA NEOADYUVANTE SEGUIDA DE ESCISIN TOTAL DEL MESORRECTO

ANTECEDENTES:Se desconocen las implicaciones diagnósticas de la invasión linfática, la invasión venosa, la invasión perineural y el crecimiento tumoral en el cáncer de recto tratado con quimiorradioterapia neoadyuvante.OBJETIVO:Este estudio fue diseñado para identificar el impacto pronóstico de la invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante.DISEÑO:Este estudio fue un estudio de cohorte retrospectivo.AJUSTES:Este estudio se realizó en el Centro Médico Samsung. La agrupación se realizó en función de la invasión linfática, la invasión venosa, la invasión perineural y el estado de crecimiento del tumor: grupo sin riesgo con 0 factores (n = 299), grupo de bajo riesgo con cualquier factor 1 (n = 131), grupo de riesgo intermedio con 2 factores cualquiera (n = 75), y un grupo de alto riesgo con 3 o 4 factores de riesgo (n = 32).PACIENTES:Se incluyeron un total de 537 pacientes que se sometieron a quimiorradioterapia neoadyuvante seguida de operación radical por cáncer de recto localmente avanzado desde enero de 2010 hasta diciembre de 2015.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la supervivencia libre de enfermedad y la supervivencia general.RESULTADOS:La mediana del período de seguimiento fue de 77 meses, y la supervivencia libre de enfermedad a los 5 años y la supervivencia general a los 5 años variaron significativamente entre los grupos en el estadio III (p < 0,001, p < 0,001). La supervivencia libre de enfermedad a los 5 años en el estadio I difirió entre el grupo sin riesgo y el grupo de riesgo intermedio (p = 0,026). En el estadio II, la supervivencia libre de enfermedad a 5 años y la supervivencia global a 5 años difirieron entre el grupo sin riesgo y el grupo de riesgo intermedio p = 0,010, p = 0,045). En el análisis multivariable, la agrupación de riesgo fue un factor pronóstico independiente tanto para la supervivencia libre de enfermedad (p < 0,001) como para la supervivencia global (p < 0,001).LIMITACIÓN:Las limitaciones inherentes están asociadas con el diseño de estudio retrospectivo de un solo centro..CONCLUSIÓN:La invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral son fuertes factores pronósticos para la supervivencia libre de enfermedad y la supervivencia general en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante. Por lo tanto, se recomienda fuertemente la quimioterapia adyuvante en pacientes con invasión linfática positiva, invasión venosa, invasión perineural y tumor en en formacion. Consulte Video Resumen en http://links.lww.com/DCR/B919 . (Traducción-Dr Yolanda Colorado ).

Tumour budding and poorly differentiated clusters in colon cancer - different manifestations of partial epithelial-mesenchymal transition

Morphological features including infiltrative growth, tumour budding (TB), and poorly differentiated clusters (PDCs) have a firmly established negative predictive value in colorectal cancer (CRC). Despite extensive research, the mechanisms underlying different tumour growth patterns remain poorly understood. The aim of this study was to investigate the involvement of epithelial-mesenchymal transition (EMT) in TB and PDCs in CRC. Using laser-capture microdissection, we obtained distinct parts of the primary CRC including TB, PDCs, expansive tumour front, and the central part of the tumour, and analysed the expression of EMT-related markers, i.e. the miR-200 family, ZEB1/2, RND3, and CDH1. In TB, the miR-200 family and CDH1 were significantly downregulated, while ZEB2 was significantly upregulated. In PDCs, miR-141, miR-200c, and CDH1 were significantly downregulated. No significant differences were observed in the expression of any EMT-related markers between the expansive tumour front and the central part of the tumour. Our results suggest that both TB and PDCs are related to partial EMT. Discrete differences in morphology and expression of EMT-related markers between TB and PDCs indicate that they represent different manifestations of partial EMT. TB seems to be closer to complete EMT than PDCs. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Oncologic outcomes of pathologic T4 and T3 colon cancer patients diagnosed with clinical T4 stage disease using preoperative computed tomography scan

BACKGROUND

The diagnostic accuracy of computed tomography (CT) for colon cancer is low, and the preoperative risk factors for locally advanced colon cancer are unknown. This study aimed to evaluate the correlation between preoperative CT scan findings and oncologic outcomes and to identify risk factors associated with locally advanced colon cancer.

MATERIALS AND METHODS

Patients diagnosed with clinical stage (cT) 4 colon cancer based on preoperative CT scan findings who underwent curative surgery between January 2005 and December 2015 were retrospectively studied. Patients were divided according to pathologic stage (pT) into pT3 (n = 114) and pT4 (n = 102).

RESULTS

The disease-free survival rate was significantly different between the pT3 and pT4 groups (88.6% vs. 68.6%, p < 0.001). The overall survival rate of the pT3 group was significantly higher than that of the pT4 group (91.2% vs. 76.5%, p = 0.002). Perineural invasion and tumor budding were identified as preoperative risk factors predisposing to pT4 staging (p = 0.044, p = 0.001).

CONCLUSION

The survival rate of pT3 patients was significantly higher than that of pT4 patients with a preoperative cT4 diagnosis. This suggests that when planning for neoadjuvant chemotherapy in locally advanced colon cancer, preoperative CT scan findings may overestimate clinical staging and lead to inappropriate treatment. Thus, there is a need for a new modality to evaluate local advancement in colon cancer.

TMPRSS4 overexpression promotes the metastasis of colorectal cancer and predicts poor prognosis of stage III-IV colorectal cancer

PURPOSE

To study in detail the expression pattern and prognostic significance of TMPRSS4 in colorectal cancer.

METHODS

The expression of TMPRSS4 protein was determined using Western blot in the colorectal cancer tissues and normal tissues. Immunohistochemistry was used to detect the TMPRSS4 expression in colorectal cancer tissues, and the clinicopathologic characteristics and prognostic significance were analyzed.

RESULTS

TMPRSS4 overexpression was associated with tumor budding, lymphovascular invasion, perineural invasion, cancerous emboli, infiltration depth, lymph node metastasis, distant metastasis, and tumor node metastasis stage (P < 0.05 for all). Interestingly, TMPRSS4 expression in the tumor budding, tumor emboli, lymph node, and liver metastatic tumor samples was higher than in the paired primary tumors. In contrast, TMPRSS4 overexpression is inversely correlated with both the overall survival and the disease-free survival of the patients with colorectal cancer (P < 0.05 for both). Also, we found that TMPRSS4 is only of significance in predicting the prognosis of stage III and IV colorectal cancer, not stage I and II.

CONCLUSIONS

TMPRSS4 was shown to be involved in the whole process of metastasis from tumor budding to lymph node and/or distant metastasis in colorectal cancer and predicted the unfavorable prognosis of stage III-IV, indicating that it is a novel target for the precise treatment of colorectal cancer with lymph node or distant organ metastasis.

Intratumoral budding: A novel prognostic biomarker for tumor recurrence and a potential predictor of nodal metastasis in uterine cervical cancer

OBJECTIVE

To evaluate the prognostic and predictive significance of lymphovascular invasion (LVI) and lymph node metastasis of intratumoral budding (ITB) and its correlation with clinicopathological parameters in patients with cervical cancer.

METHODS

Total 151 patients with cervical cancer who underwent radical hysterectomy with pelvic and/or paraaortic lymphadenectomy were included. We assessed the status of ITB and peritumoral budding (PTB) in all available hematoxylin and eosin-stained specimens. Univariate and multivariate analyses were performed for ITB, PTB, and other clincopathological parameters as predictors of recurrence.

RESULTS

ITB^high (≥3TB/HPF) was significantly associated with large tumor size, deep stromal invasion, LVI, parametrial invasion, and lymph node metastasis. The numbers of ITBs and PTBs were positively correlated (r² = 0.754, p < 0.0001). ITB^high was more frequently observed in squamous cell carcinoma compared with adenocarcinoma and adenosquamous cell carcinoma (p = 0.010). ITB^high was found to be an independent prognostic factor for tumor recurrence by multivariate analysis (hazard ratio, 1.92; 95% confidence interval [CI], 1.37-9.90; p = 0.026). Multiple logistic regression showed association of LVI (odds ratio [OR], 1.85; 95% CI, 1.11-3.06; p = 0.017) and lymph node metastasis (OR, 1.96; 95% CI, 1.26-4.66; p = 0.019).

CONCLUSION

ITB^high is an independent prognostic factor for tumor recurrence. ITB is a surrogate marker for predicting LVI in cervical cancers. The evaluation of ITB may be readily applied in the clinical setting for improved prognosis and to guide the clinical management of patients with cervical cancer.

Tumor budding in upper urinary tract urothelial carcinoma: a putative prognostic factor for extraurothelial recurrence and overall survival

Tumor budding, defined as a single cancer cell or clusters of fewer than five cancer cells observed at the tumor invasion front, has been reported to be associated with poor prognosis in various types of cancers. However, limited information regarding the pathological and prognostic significance of tumor budding in upper urinary tract urothelial carcinoma (UUTUC) is available. We investigated 135 consecutive patients with newly diagnosed invasive UUTUCs (73 with renal pelvic cancers and 62 with ureteral cancers) treated with nephroureterectomy or partial ureterectomy between 1999 and 2018 in our hospital. Under a × 200 magnification, tumors with 10 or more budding foci were defined as "high tumor budding". The median follow-up period was 53.6 months. Among the 135 patients, 41 (30%; 16 with renal pelvic cancers and 25 with ureteral cancers) showed high tumor budding. High tumor budding was related to adjuvant chemotherapy status, higher pathological T stage, lymphovascular invasion, lymph node metastasis, tumor location, concomitant variant histology, and non-papillary gross finding. The multivariate Cox analysis revealed that LVI and high tumor budding were independent predictors for extraurothelial recurrence (P = 0.039 and 0.014, hazard ratio = 2.50 and 2.88, respectively), and high tumor budding was an independent predictor for overall survival (P = 0.024, hazard ratio = 2.33). Tumor budding can be easily introduced in clinical practice with no need for immunohistochemical analysis, may be an important clinicopathological factor of UUTUC, and is suggested to be useful as a novel predictive prognostic factor of patients with invasive UUTUC.

Pathologic assessment of endoscopic resection specimens with superficial carcinoma of the esophagus: current practice and practical issues

Endoscopic resection (ER) has become the first-line therapy for early esophageal cancer and offers a treatment alternative to surgery, owing to less morbidity and better quality of life. ER techniques include endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). EMR is faster, simpler, and cheaper than ESD, but limited by its ability to resect lesions larger than 1.5 centimeters. Piecemeal EMR has limitations, including a high local recurrence rate and a suboptimal specimen for an accurate pathologic assessment. ESD, on the other hand, allows en bloc resections with negative (R0) margins, irrespective of lesion size, providing an excellent pathologic specimen, however, is technically challenging with a higher risk of complications. The evaluation of ER specimens in pathology varies slightly from institution to institution. Our review summarizes the current practices and issues in the pathologic assessment of esophageal ER specimens, which highlights the necessity of a systematic approach and standardization of both macroscopic and microscopic evaluation. There is a need for a comprehensive and standardized pathology report that will allow for uniform terminology for endoscopists, surgeons, and pathologists, which, in turn, will result in better treatment guidance.

Tumor budding in cervical cancer as a prognostic factor and its possible role as an additional intermediate-risk factor

OBJECTIVE

To evaluate the prognostic value and its possible role as an additional intermediate-risk factor of tumor budding (TB) in cervical cancer following radical hysterectomy.

METHODS

In total, 136 patients with cervical cancer who underwent radical hysterectomy with pelvic and/or paraaortic lymphadenectomy were included. We assessed the status of TB in available hematoxylin and eosin-stained specimens. Univariate and multivariate analyses for predicting tumor recurrence and death were performed using TB and other clinicopathologic parameters. To evaluate additional intermediate-risk factors of TB, patients who had at least one high-risk factor were excluded, and a total of 81 patients were included. We added TB to three conventional intermediate-risk models and compared their performance with new and conventional models using the log-rank test and receiver operating characteristic analysis.

RESULTS

High TB was defined as ≥5 per high-power field for disease-free survival and ≥ 8 per high-power field for overall survival. Multivariate analysis revealed that high TB was an independent prognostic factor for predicting overall survival (hazard ratio, 4.96; 95% confidence intervals, 1.06-23.29; p = .0423). The addition of TB to the conventional intermediate-risk models improved the accuracy of recurrence prediction. Among the risk models, the new model using at least two risk factors, including tumor size (≥ 4 cm), deep stromal invasion (outer one-third of entire cervical thickness), lymphovascular invasion, and high TB, was the most accurate for predicting tumor recurrence (area under the curve, 0.708, hazard ratio, 4.25; p = .0231).

CONCLUSION

High TB may be a prognostic biomarker of cervical cancer. Moreover, the addition of TB to the conventional intermediate-risk models improves the stratification of tumor recurrence.

The relationship between tumor budding and survival in colorectal carcinomas

OBJECTIVE

Tumor budding is a parameter that is increasingly understood in colorectal carcinomas. We aimed to investigate the relationship between tumor budding, prognostic factors, and survival.

METHODS

A total of 185 patients who had undergone colorectal surgery were observed. Tumor budding, the tumor budding score, and the relationship between these and prognostic factors, and survival investigated.

RESULTS

Tumor budding was found in 91 (49.2%) cases. The relationship between the tumor budding score and histological grade, lymphovascular invasion, perineural invasion, pathological lymph node stage, and mortality rates were significant.

CONCLUSION

In our study, the relationship between tumor budding and survival is very strong. Considering these findings and the literature, the prognostic significance of tumor budding becomes clear and should be stated in pathology reports.

Assessment of individual tumor buds using keratin immunohistochemistry: moderate interobserver agreement suggests a role for machine learning

Tumor budding is a promising and cost-effective biomarker with strong prognostic value in colorectal cancer. However, challenges related to interobserver variability persist. Such variability may be reduced by immunohistochemistry and computer-aided tumor bud selection. Development of computer algorithms for this purpose requires unequivocal examples of individual tumor buds. As such, we undertook a large-scale, international, and digital observer study on individual tumor bud assessment. From a pool of 46 colorectal cancer cases with tumor budding, 3000 tumor bud candidates were selected, largely based on digital image analysis algorithms. For each candidate bud, an image patch (size 256 × 256 µm) was extracted from a pan cytokeratin-stained whole-slide image. Members of an International Tumor Budding Consortium (n = 7) were asked to categorize each candidate as either (1) tumor bud, (2) poorly differentiated cluster, or (3) neither, based on current definitions. Agreement was assessed with Cohen's and Fleiss Kappa statistics. Fleiss Kappa showed moderate overall agreement between observers (0.42 and 0.51), while Cohen's Kappas ranged from 0.25 to 0.63. Complete agreement by all seven observers was present for only 34% of the 3000 tumor bud candidates, while 59% of the candidates were agreed on by at least five of the seven observers. Despite reports of moderate-to-substantial agreement with respect to tumor budding grade, agreement with respect to individual pan cytokeratin-stained tumor buds is moderate at most. A machine learning approach may prove especially useful for a more robust assessment of individual tumor buds.

The prognostic value of tumor budding in patients who had surgery for rectal cancer with and without neoadjuvant therapy

BACKGROUND

The aim of this study was to investigate the prognostic value of tumor budding (TB) in rectal cancer patients. TB in the specimens of patients who received neoadjuvant chemoradiotherapy was specifically analyzed.

METHODS

This study was conducted on rectal cancer patients treated at Dokuz Eylul University Hospital, Turkey, between January 2000 and June 2010. Prospectively recorded clinicopathological data and the oncological outcomes of patients who received neoadjuvant chemoradiotherapy (CRT) (n = 117) and also patients who did not receive it (n = 113) were analyzed. TB was defined as an isolated single cancer cell or a cluster of cells composed of less than 5 cells of a "budding focus". Budding intensity was scored as follows: none (0), mild (1-5 buds), moderate (6-10 buds), and severe (> 10 buds). Two tumor budding intesity groups were created, TB-1 (none, few) and TB-2 (moderate, severe) for statistical analysis.

RESULTS

The median follow-up time was 40.12 ± 27.5 months. The 5-year overall and disease-free survival (DFS) rates were 66% and 62%, respectively. Multivariate analysis of overall survival in all patients showed that TB intensity (HR 2.64; 95% CI 1.46-4.77) and radial margin status (HR 2.16; 95% CI 1.18-3.96) were independent predictors of decreased overall survival. In patients who received CRT, TB (HR 4.87; 95% CI 2.10-11.28) and distant metastasis (HR 4.31; 95% CI 1.81-10.22) were predictive of survival while in patients who did not receive CRT, TB (HR 4.28; 95% CI 1.60-11.49), distant metastasis (HR 2.33; 95% CI 1.19-4.60), radial margin status (HR 2.53; 95% CI 1.09-5.91), and venous invasion (HR 4.48; 95% CI 2.14-9.39) were significantly independent predictors of survival. In multivariate analysis of all patients decreased DFS was correlated with lymph node involvement (HR 2.78; 95% CI 1.60-4.87), venous invasion (HR 1.76; 95% CI 1.00-3.09), and with radial margin status (HR 2.31; 95% CI 1.27-4.22). In multivariate analysis in the CRT group, decreased DFS was significantly associated with lymph node involvement (HR 4.39; 95% CI 1.70-11.33) and radial margin status (HR 2.56; 95% CI 1.12-5.90) while only lymph node involvement (HR 2.33; 95% CI 1.16-4.66) was a significant predictor of decreased DFS in patients who did not receive CRT.

CONCLUSIONS

TB has prognostic value as important as lymph node involvement and radial margin status and it may be a helpful prognostic indicator even after CRT. TB should be included in the TNM classification and may be used in planning adjuvant therapy.

Tumor budding for predicting prognosis of resected rectum cancer after neoadjuvant treatment

BACKGROUND

Rectum cancer is a type of colorectal cancer. Its etiology and etiopathogenesis are similar to other colon diseases. We aimed to evaluate the tumor budding for predicting prognosis of resected rectum cancer patients.

METHODS

We retrospectively collected the data of 75 operated rectum adenocarcinoma patients who were treated neoadjuvant chemoradiotherapy between 2013 and 2018 in Umraniye Research and Training Hospital and Acıbadem University Medical Oncology Outpatient Clinic. Tumor budding was investigated as a prognostic factor for disease-free survival.

RESULTS

This study included 75 rectum cancer patients and 51 were male (68%). Median age was 56 (range 19 to 77 years). There were 29 (39%) and 46 (61%) patients in tumor budding low-intermediate and high groups respectively. In multivariate analysis, tumor budding was found to be an independent prognostic factor for disease-free survival (p = 0.00).

CONCLUSIONS

According to our study, having high tumor budding suggests a high likelihood of relapse. Therefore, we might need additional follow-up protocol in these patients.

Automatic evaluation of tumor budding in immunohistochemically stained colorectal carcinomas and correlation to clinical outcome

Background

Tumor budding, meaning a detachment of tumor cells at the invasion front of colorectal carcinoma (CRC) into single cells or clusters (<=5 tumor cells), has been shown to correlate to an inferior clinical outcome by several independent studies. Therefore, it has been discussed as a complementary prognostic factor to the TNM staging system, and it is already included in national guidelines as an additional prognostic parameter. However, its application by manual evaluation in routine pathology is hampered due to the use of several slightly different assessment systems, a time-consuming manual counting process and a high inter-observer variability. Hence, we established and validated an automatic image processing approach to reliably quantify tumor budding in immunohistochemically (IHC) stained sections of CRC samples.

Methods

This approach combines classical segmentation methods (like morphological operations) and machine learning techniques (k-means and hierarchical clustering, convolutional neural networks) to reliably detect tumor buds in colorectal carcinoma samples immunohistochemically stained for pan-cytokeratin. As a possible application, we tested it on whole-slide images as well as on tissue microarrays (TMA) from a clinically well-annotated CRC cohort.

Results

Our automatic tumor budding evaluation tool detected the absolute number of tumor buds per image with a very good correlation to the manually segmented ground truth (R2 value of 0.86).

Furthermore the automatic evaluation of whole-slide images from 20 CRC-patients, we found that neither the detected number of tumor buds at the invasion front nor the number in hotspots was associated with the nodal status. However, the number of spatial clusters of tumor buds (budding hotspots) significantly correlated to the nodal status (p-value = 0.003 for N0 vs. N1/N2). TMAs were not feasible for tumor budding evaluation, as the spatial relationship of tumor buds (especially hotspots) was not preserved.

Conclusions

Automatic image processing is a feasible and valid assessment tool for tumor budding in CRC on whole-slide images. Interestingly, only the spatial clustering of the tumor buds in hotspots (and especially the number of hotspots) and not the absolute number of tumor buds showed a clinically relevant correlation with patient outcome in our data.

Electronic supplementary material

The online version of this article (10.1186/s13000-018-0739-3) contains supplementary material, which is available to authorized users.

Prognostic Impact of Tumor-Budding Grade in Stages 1-3 Colon Cancer: A Retrospective Cohort Study

BACKGROUND

Tumor budding is associated with adverse histology and is a predictor of lymph node metastasis. However, it remains unclear whether tumor budding is predictive of a poor prognosis for colon cancer patients. This study sought to investigate the prognostic significance of tumor budding in colon cancer.

METHODS

This study evaluated 4196 colon cancer patients who underwent radical surgery from 2007 to 2013 at a single institution. The patients were categorized according to tumor-budding status. Adjustment was made for using propensity score-matched analysis, and both disease-free survival (DFS) and overall survival (OS) were compared between the groups.

RESULTS

Among the 4196 patients, 2269 had low budding (< 5 buds), 1312 had intermediate budding (5-9 buds), and 615 had high budding (≥ 10 buds). High budding was associated with adverse histologic features such as elevated levels of preoperative carcinoembryonic antigen, advanced stage, poor histology, and the presence of lymphatic/vascular/perineural invasion. Before matching, DFS and OS decreased significantly with increasing tumor budding. After matching, the difference in survival between the low- and intermediate-budding groups disappeared. However, the OS and DFS rates for the high-budding group were significantly lower than for the other two groups. In the multivariate analysis of prognostic factors, high budding was an independent poor prognostic factor in DFS and OS, whereas tumor-budding positivity itself was not an independent prognostic factor.

CONCLUSION

Tumor-budding grade rather than tumor-budding positivity was an independent prognostic factor in colon cancer.

Use of a combination of CEA and tumor budding to identify high-risk patients with stage II colon cancer

BACKGROUND

High-risk patients with stage II colon cancer may benefit from adjuvant chemotherapy, but identifying this patient population can be difficult. We assessed the prognosis value for predicting tumor progression in patients with stage II colon cancer, of a panel of 2 biomarkers for colon cancer: tumor budding and preoperative carcinoembryonic antigen (CEA).

METHODS

Consecutive patients (N = 134) with stage II colon cancer who underwent curative surgery from 2000 to 2007 were included. Multivariate analysis was used to evaluate the association of CEA and tumor budding grade with 5-year disease-free survival (DFS). The prognostic accuracy of CEA, tumor budding grade and the combination of both (CEA-budding panel) was determined.

RESULTS

The study found that both CEA and tumor budding grade were associated with 5-year DFS. The prognostic accuracy for disease progression was higher for the CEA-budding panel (82.1%) than either CEA (70.9%) or tumor budding grade (72.4%) alone.

CONCLUSIONS

The findings indicate that the combination of CEA levels and tumor budding grade has greater prognostic value for identifying patients with stage II colon cancer who are at high-risk for disease progression, than either marker alone.

Tumor budding, a novel prognostic indicator for predicting stage progression in T1 bladder cancers

Tumor budding has been defined as an isolated single cancer cell or a cluster composed of fewer than five cancer cells scattered in the stroma. It is a strong predictor for lymph node metastasis in T1 colorectal cancer. We introduced this concept to T1 non‐muscle invasive bladder cancer and evaluated whether tumor budding could have a prognostic impact on the clinical outcome. We identified 121 consecutive patients with newly diagnosed T1 bladder cancer between 1994 and 2014 at Keio University Hospital. All slides were re‐reviewed by a dedicated uropathologist. Budding foci were counted under ×200 magnification. When the number of budding foci was 10 or more, tumor budding was defined as positive. The relationship between tumor budding and clinical outcomes was assessed using a multivariate analysis. The median follow‐up was 52 months. Tumor budding was positive in 21 patients (17.4%). Tumor budding was significantly associated with T1 substaging, tumor architecture and lymphovascular invasion. The 5‐year progression‐free survival rate in T1 bladder cancer patients with tumor budding was 53.8%, which was significantly lower than that in patients without tumor budding (88.4%, P = 0.001). A multivariate Cox regression analysis revealed that tumor budding was independently associated with stage progression (P = 0.002, hazard ratio = 4.90). In a subgroup of patients treated with bacillus Calmette‐Guérin instillation (n = 88), tumor budding was also independently associated with stage progression (P = 0.003, hazard ratio = 5.65). Tumor budding may be a novel indicator for predicting stage progression in T1 bladder cancer, and would likely be easily introduced in clinical practice.

Tumour Budding and Survival in Stage II Colorectal Cancer: a Systematic Review and Pooled Analysis

PURPOSE

Tumour budding is defined as the presence of isolated or small clusters of malignant cells at the invasive edge of the tumour. It is considered a negative prognostic factor in colorectal cancer (CRC) and is associated with a poor outcome and adverse pathological features. Here, we report a meta-analysis of the association of tumour budding and survival in stage II CRC patients.

METHODS

PubMed, EMBASE, Web of Science and SCOPUS were searched for studies that assessed the relationship between tumour budding and 5-year overall survival (OS) in stage II CRC patients. Published data were extracted and used to compute odds ratios (ORs) for death at 5 years and hazard ratios (HRs) for survival amongst patients with respect to the extent of tumour budding, using multivariate analysis. Data were pooled using the Mantel-Haenszel random effect model.

RESULTS

We analysed 12 studies that included a total of 1652 patients. High-grade budding was associated with worse OS at 5 years (OR for death, 6.25; 95 % confidence interval [CI], 4.04-9.67; P < 0.00001). The absolute difference in 5-year OS was -25 % (95 % CI, -18- - 33 %, P < 0.00001). It was particularly noteworthy that the presence of high-grade budding was associated with an increased risk of death (HR for death, 3.68; 95 % CI, 2.16-6.28, P < 0.00001).

CONCLUSIONS

Tumour budding is associated with worse survival in stage II CRC, in particular in pT3N0M0 patients. It could therefore potentially be used when deciding whether to administer adjuvant chemotherapy in high-risk node negative CRC patients.

Tumor Budding: The Name is EMT. Partial EMT

Tumor budding is a histological phenomenon encountered in various cancers, whereby individual malignant cells and/or small clusters of malignant cells are seen in the tumor stroma. Postulated to be mirror epithelial-mesenchymal transition, tumor budding has been associated with poor cancer outcomes. However, the vast heterogeneity in its exact definition, methodology of assessment, and patient stratification need to be resolved before it can be routinely used as a standardized prognostic feature. Here, we discuss the heterogeneity in defining and assessing tumor budding, its clinical significance across multiple cancer types, and its prospective implementation in clinical practice. Next, we review the emerging evidence about partial, rather than complete, epithelial-mesenchymal phenotype at the tumor bud level, and its connection with tumor proliferation, quiescence, and stemness. Finally, based on recent literature, indicating a co-expression of epithelial and mesenchymal markers in many tumor buds, we posit tumor budding to be a manifestation of this hybrid epithelial/mesenchymal phenotype displaying collective cell migration.

Tumour budding in colorectal cancer: what do we know and what can we do?

Budding is a process during which individual or small clusters of up to five tumour cells detach from the main tumour mass and invade into the surrounding stroma. In colorectal cancer, this feature is observed in 20-40% of cases and is associated with lymphovascular invasion, lymph node and distant metastases, and poor prognosis. A variety of scoring systems for budding have been proposed but so far a gold standard is lacking, hampering implementation of a budding score in guidelines for pathological examination of colorectal cancer. Furthermore, little is known about the mechanisms which cause tumour cells to detach from the main tumour mass and obtain increased invasive potential. In this review, we present an overview of tumour budding including its definition, scoring systems, prognostic relevance and biological mechanisms involved.

Integrin αvβ6 sustains and promotes tumor invasive growth in colon cancer progression

AIM: To detect the mechanism by which colon tumor escapes the growth constraints imposed on normal cells by cell crowding and dense pericellular matrices.

METHODS: An immunohistochemical study of integrin αvβ6 and matrix metalloproteinase-9 (MMP-9) was performed on tissue microarrays of 200 spots, including 100 cases of colon tumors.

RESULTS: High immunoreactivity for αvβ6 (73.7%; 28/38) and MMP-9 (76.5%; 52/68) was observed in invasive tumor portions. Furthermore, the effects of integrin αvβ6 on tumor invasive growth in nude mice were detected. Tumor invasive growth and high expression of both αvβ6 and MMP-9 were only seen in tumors resulting from WiDr cells expressing αvβ6 in the tumorigenicity assay. Flow cytometry was applied to analyze αvβ6 expression in colon cancer WiDr and SW480 cells. The effects of cell density on αvβ6 expression and MMP-9 secretion were also detected by Biotrak MMP-9 activity assay and gelatin zymography assay. High cell density evidently enhanced αvβ6 expression and promoted MMP-9 secretion compared with low density.

CONCLUSION: Integrin αvβ6 sustains and promotes tumor invasive growth in tumor progression via a self-perpetuating mechanism. Integrin ανβ6-mediated MMP-9 secretion facilitates pericellular matrix degradation at high cell density, which provides the basis of invasive growth.

Actin cytoskeletal control during epithelial to mesenchymal transition: focus on the pancreas and intestinal tract

The formation of epithelial tissues allows organisms to specialise and form tissues with diverse functions and compartmentalised environments. The tight controls on cell growth and migration required to maintain epithelia can present problems such as the development and spread of cancer when normal pathways are disrupted. By attaining a deeper understanding of how cell migration is suppressed to maintain the epithelial organisation and how it is reactivated when epithelial tissues become mesenchymal, new insights into both cancer and development can be gained. Here we discuss recent developments in our understanding of epithelial and mesenchymal regulation of the actin cytoskeleton in normal and cancerous tissue, with a focus on the pancreas and intestinal tract.

Management of malignant colon polyps: Current status and controversies

Colon cancer remains a significant clinical problem worldwide and in the United States it is the third most common cancer diagnosed in men and women. It is generally accepted that most malignant neoplasms of the colon arise from precursor adenomatous polyps. This stepwise progression of normal epithelium to carcinoma, often with intervening dysplasia, occurs as a result of multiple sequential, genetic mutations-some are inherited while others are acquired. Malignant polyps are defined by the presence of cancer cells invading through the muscularis mucosa into the underlying submucosa (T1). They can appear benign endoscopically but the presence of malignant invasion histologically poses a difficult and often controversial clinical scenario. Emphasis should be initially focused on the endoscopic assessment of these lesions. Suitable polyps should be resected en-bloc, if possible, to facilitate thorough evaluation by pathology. In these cases, proper attention must be given to the risks of residual cancer in the bowel wall or in the surrounding lymph nodes. If resection is not feasible endoscopically, then these patients should be referred for surgical resection. This review will discuss the important prognostic features of malignant polyps that will most profoundly affect this risk profile. Additionally, we will discuss effective strategies for their overall management.

Tumor budding in colorectal carcinoma assessed by cytokeratin immunostaining and budding areas: possible involvement of c-Met

Tumor budding/sprouting has been shown to be an independent adverse prognostic factor in T1 and T3N0 colorectal carcinomas, however, its assessment could be improved by more accurate identification of budding carcinoma cells and consideration of budding areas. Moreover, tumor budding mechanisms are yet to be defined. In this study, we evaluated the identification of budding tumor cells by either H&E staining alone or H&E with immunohistochemistry and developed a scoring system based on budding grades and areas. We examined whether the budding score correlated with clinicopathologic features and prognosis and the association between tumor budding/sprouting and c-Met protein expression and phosphorylation and MET gene copy numbers because c-Met is known to play an important role in colorectal carcinoma tumorigenesis. Cytokeratin immunohistochemistry could identify tumors with shorter disease-free survival (DFS) from the low-grade budding group assessed with H&E alone. High budding scores based on budding grade and area were more significantly correlated with DFS than scores obtained using the budding grade alone. In tumors with a high budding score, c-Met expression and phosphorylation levels and MET gene copy numbers were significantly increased at the invasive front compared with those in superficial tumor portions. This study showed for the first time that high levels of phospho-c-Met at the invasive front were significantly associated with a high budding score and shorter DFS. In conclusion, a budding score assessed by budding grades and budding-positive areas correlates highly with clinicopathologic aggressive features of colorectal carcinoma.

Tumor budding in upper gastrointestinal carcinomas

The basis of personalized medicine in oncology is the prediction of an individual's risk of relapse and death from disease. The presence of tumor budding (TB) at the tumor-host interface of gastrointestinal cancers has been recognized as a hallmark of unfavorable disease biology. TB is defined as the presence of dedifferentiated cells or small clusters of up to five cells at the tumor invasive front and can be observed in aggressive carcinomas of the esophagus, stomach, pancreas, ampulla, colon, and rectum. Presence of TB reproducibly correlates with advanced tumor stage, frequent lymphovascular invasion, nodal, and distant metastasis. The UICC has officially recognized TB as additional independent prognostic factor in cancers of the colon and rectum. Recent studies have also characterized TB as a promising prognostic indicator for clinical management of esophageal squamous cell carcinoma, adenocarcinoma of the gastro-esophageal junction, and gastric adenocarcinoma. However, several important issues have to be addressed for application in daily diagnostic practice: (1) validation of prognostic scoring systems for TB in large, multi-center studies, (2) consensus on the optimal assessment method, and (3) inter-observer reproducibility. This review provides a comprehensive analysis of TB in cancers of the upper gastrointestinal tract including critical appraisal of perspectives for further study.

Controversies in the pathological assessment of colorectal cancer

Pathologic assessment of colorectal cancer specimens plays an essential role in patient management, informing prognosis and contributing to therapeutic decision making. The tumor-node-metastasis (TNM) staging system is a key component of the colorectal cancer pathology report and provides important prognostic information. However there is significant variation in outcome of patients within the same tumor stage. Many other histological features such as tumor budding, vascular invasion, perineural invasion, tumor grade and rectal tumor regression grade that may be of prognostic value are not part of TNM staging. Assessment of extramural tumor deposits and peritoneal involvement contributes to TNM staging but there are some difficulties with the definition of both of these features. Controversies in colorectal cancer pathology reporting include the subjective nature of some of the elements assessed, poor reporting rates and reproducibility and the need for standardized examination protocols and reporting. Molecular pathology is becoming increasingly important in prognostication and prediction of response to targeted therapies but accurate morphology still has a key role to play in colorectal cancer pathology reporting.

Tumor budding in the clinical management of colon and rectal cancer

SUMMARY 

Morphological features of the tumor microenvironment are emerging as powerful prognostic indicators for colorectal cancer (CRC). The presence of peritumoral budding (PTB), defined as the presence of single tumor cells or small clusters of up to five cells in the tumor stroma ahead of the invasive front, is a hallmark of aggressive disease biology. Presence of PTB strongly correlates with adverse clinicopathological features and is recognized as an additional adverse prognostic factor by the Union for International Cancer Control. Recent studies have also characterized intratumoral budding (ITB) in biopsy material as a prognostic indicator in the preoperative setting. This paper provides a comprehensive overview on the role of PTB and ITB in the clinical management of colon and rectal cancer.

Prognostic stratification of colorectal cancer patients: current perspectives

Tumor staging according to the American Joint Committee on Cancer/Union for International Cancer Control tumor, node, metastasis (TNM) system is currently regarded as the standard for staging of patients with colorectal cancer. This system provides the strongest prognostic information for patients with early stage disease and those with advanced disease. For patients with intermediate levels of disease, it is less able to predict disease outcome. Therefore, additional prognostic markers are needed to improve the management of affected patients. Ideal markers are readily assessable on hematoxylin and eosin-stained tumor slides, and in this way are easily applicable worldwide. This review summarizes the histological features of colorectal cancer that can be used for prognostic stratification. Specifically, we refer to the different histological variants of colorectal cancer that have been identified, each of these variants carrying distinct prognostic significance. Established markers of adverse outcomes are lymphatic and venous invasion, as well as perineural invasion, but underreporting still occurs in the routine setting. Tumor budding and tumor necrosis are recent advances that may help to identify patients at high risk for recurrence. The prognostic significance of the antitumor inflammatory response has been known for quite a long time, but a lack of standardization prevented its application in routine pathology. However, scales to assess intra- and peritumoral inflammation have recently emerged, and can be expected to strengthen the prognostic significance of the pathology report.

Tumour budding is a reproducible index for risk stratification of patients with stage II colon cancer

AIM

High-risk patients with Stage II colon cancer may benefit from adjuvant chemotherapy, but it is difficult to identify such a patient group. A robust and reproducible index would be helpful to select the subset of Stage II colon cancer patients at high risk. This study investigated the potential prognostic significance of tumour budding in Stage II colon cancer.

METHOD

In all, 135 Stage II colon cancer patients with known outcome were identified. The degree of tumour budding was assessed by two individual observers and was classified, according to the number of tumour buds in the area with the greatest budding intensity on haematoxylin and eosin slides, as high-grade budding (10 or more tumour buds) and low-grade budding (0-9 buds). Inter-observer agreement for two observers was assessed by using the kappa test. Progression-free and cancer-specific survivals were analysed using the Kaplan-Meier method and Cox regression.

RESULTS

The 5-year progression-free survival rates for patients with high-grade tumour budding (n = 36) and those with low-grade budding (n = 99) were 57.6% and 89.0% (P < 0.001). The 5-year cancer-specific survival rates were 66.7% vs 92.0% (P < 0.001). Cox regression analyses demonstrated tumour budding as an independent predictor of disease progression (hazard ratio 4.982, P < 0.001) and cancer-related death (hazard ratio 4.142, P = 0.003). The two observers agreed on the classification of tumour budding in 118 cases (87.4%) and the inter-observer agreement was good (κ = 0.692).

CONCLUSION

Tumour budding is a strong and reproducible prognostic factor for adverse outcome in Stage II colon cancer, which may serve as a prognostic marker to identify patients with a high risk of recurrence who may benefit from adjuvant therapy.

Site-specific tumor grading system in colorectal cancer: multicenter pathologic review of the value of quantifying poorly differentiated clusters

The study aimed to determine the value of a novel site-specific grading system based on quantifying poorly differentiated clusters (PDC; Grade(PDC)) in colorectal cancer (CRC). A multicenter pathologic review involving 12 institutions was performed on 3243 CRC cases (stage I, 583; II, 1331; III, 1329). Cancer clusters of ≥5 cancer cells and lacking a gland-like structure (PDCs) were counted under a ×20 objective lens in a field containing the maximum clusters. Tumors with <5, 5 to 9, and ≥10 PDCs were classified as grades G1, G2, and G3, respectively. According to Grade(PDC), 1594, 1005, and 644 tumors were classified as G1, G2, and G3 and had 5-year recurrence-free survival rates of 91.6%, 75.4%, and 59.6%, respectively (P<0.0001). Multivariate analysis showed that Grade exerted an influence on prognostic outcome independently of TNM staging; approximately 20% and 46% of stage I and II patients, respectively, were selected by Grade(PDC) as a population whose survival estimate was comparable to or even worse than that of stage III patients. Grade(PDC) surpassed TNM staging in the ability to stratify patients by recurrence-free survival (Akaike information criterion, 2915.6 vs. 2994.0) and had a higher prognostic value than American Joint Committee on Cancer (AJCC) grading (Grade(AJCC)) at all stages. Regarding judgment reproducibility of grading tumors, weighted κ among the 12 institutions was 0.40 for Grade(AJCC) and 0.52 for Grade(PDC). Grade(PDC) has a robust prognostic power and promises to be of sufficient clinical value to merit implementation as a site-specific grading system in CRC.

Intratumoural budding (ITB) in preoperative biopsies predicts the presence of lymph node and distant metastases in colon and rectal cancer patients

Background:

In colorectal cancer (CRC), tumour budding at the invasion front is associated with lymph node (LN) and distant metastasis. Interestingly, tumour budding can also be detected in biopsies (intratumoural budding; ITB) and may have similar clinical importance. Here we investigate whether ITB in preoperative CRC biopsies can be translated into daily diagnostic practice.

Methods:

Preoperative biopsies from 133 CRC patients (no neoadjuvant therapy) underwent immunohistochemistry for pan-cytokeratin marker AE1/AE3. Across all biopsies for each patient, the densest region of buds at × 40 (high-power field; HPF) was identified and buds were counted.

Results:

A greater number of tumour buds in the biopsy was associated with pT stage (P=0.0143), LN metastasis (P=0.0007), lymphatic (P=0.0065) and venous vessel invasion (P=0.0318) and distant metastasis (cM1) (P=0.0013). Using logistic regression, a ‘scale' was developed to estimate the probability of LN and distant metastasis using the number of tumour buds (e.g. 10 buds per HPF: 64% chance of LN metastasis; 30 buds per HPF: 86% chance). Inter-observer agreement for ITB was excellent (intraclass correlation coefficient: 0.813).

Conclusion:

Tumour budding can be assessed in the preoperative biopsy of CRC patients. It is practical, reproducible and predictive of LN and distant metastasis. Intratumoural budding qualifies for further investigation in the prospective setting.

Proposal for a 10-high-power-fields scoring method for the assessment of tumor budding in colorectal cancer

Although tumor budding is linked to adverse prognosis in colorectal cancer, it remains largely unreported in daily diagnostic work due to the absence of a standardized scoring method. Our aim was to assess the inter-observer agreement of a novel 10-high-power-fields method for assessment of tumor budding at the invasive front and to confirm the prognostic value of tumor budding in our setting of colorectal cancers. Whole tissue sections of 215 colorectal cancers with full clinico-pathological and follow-up information were stained with cytokeratin AE1/AE3 antibody. Presence of buds was scored across 10-high-power fields at the invasive front by two pathologists and two additional observers were asked to score 50 cases of tumor budding randomly selected from the larger cohort. The measurements were correlated to the patient and tumor characteristics. Inter-observer agreement and correlation between observers' scores were excellent (P<0.0001; intraclass correlation coefficient=0.96). A test subgroup of 65 patients (30%) was used to define a valid cutoff score for high-grade tumor budding and the remaining 70% of the patients were entered into the analysis. High-grade budding was defined as an average of ≥10 buds across 10-high-power fields. High-grade budding was associated with a higher tumor grade (P<0.0001), higher TNM stage (P=0.0003), vascular invasion (P<0.0001), infiltrating tumor border configuration (P<0.0001) and reduced survival (P<0.0001). Multivariate analysis confirmed its independent prognostic effect (P=0.007) when adjusting for TNM stage and adjuvant therapy. Using 10-high-power fields for evaluating tumor budding has independent prognostic value and shows excellent inter-observer agreement. Like the BRE and Gleason scores in breast and prostate cancers, respectively, tumor budding could be a basis for a prognostic score in colorectal cancer.

Novel biomarkers for the prediction of metastasis in colorectal cancer

INTRODUCTION

In patients with metastatic colorectal cancers, multimodal management and the use of biological agents such as monoclonal antibodies have had major positive effects on survival. The ability to predict which patients may be at 'high risk' of distant metastasis could have major implications on patient management. Histomorphological, immunohistochemical or molecular biomarkers are currently being investigated in order to test their potential value as predictors of metastasis.

AREAS COVERED

Here, the author reviews the clinical and functional data supporting the investigation of three novel promising biomarkers for the prediction of metastasis in patients with colorectal cancer: tumor budding, Raf1 kinase inhibitor protein (RKIP) and metastasis-associated in colon cancer-1 (MACC1).

EXPERT OPINION

The lifespan of most potential biomarkers is short as evidenced by the rare cases that have successfully made their way into daily practice such as KRAS or microsatellite instability (MSI) status. Although the three biomarkers reviewed herein have the potential to become important predictive biomarkers of metastasis, they have similar hurdles to overcome before they can be implemented into clinical management: standardization and validation in prospective patient cohorts.

Epithelial mesenchymal transition in colorectal cancer: Seminal role in promoting disease progression and resistance to neoadjuvant therapy

BACKGROUND

Epithelial mesenchymal transition (EMT) may be physiological as part of embryological development, or pathological as part of cancer development. It is one of the key initiating events in the metastatic cascade. EMT has profound effects on tumour cell invasiveness, proliferation and motility. In the present article we aimed to review the potential role of EMT as a process to explain colorectal cancer progression and resistance to neoadjuvant therapy.

METHODS

Extensive literature searches were performed in Pubmed, EMBASE and Google Scholar databases to identify relevant articles published before March 2012.

RESULTS

There is adequate evidence to support the complex upstream signalling alterations needed for EMT to occur in colorectal cancers. Changes of EMT are likely to be found at the tumour invasive front: the deepest, growing tumour margin. Loss of E-cadherin at the cell membrane causes loss of cellular integrity, with subsequent migration of malignant cells and tumour budding. These processes are associated with metastases and recurrence of colorectal cancer. There is early evidence from a limited number of studies that resistance to neoadjuvant therapy in colorectal cancer is associated with changes of EMT. However, there is a lack of supporting evidence originating from human colorectal cancer tissues.

CONCLUSIONS

Emerging evidence demonstrates that development of EMT in colorectal cancer leads to an aggressive phenotype that may promote metastatic spread, and augment treatment resistance during neoadjuvant therapy. A clearer understanding of the processes and role of EMT in colorectal cancer may also highlight novel therapeutic strategies.

Tumour budding and the expression of cancer stem cell marker aldehyde dehydrogenase 1 in nasopharyngeal carcinoma

AIMS

To detect the prognostic significance of tumour budding and its expression of aldehyde dehydrogenase 1 (ALDH1) in nasopharyngeal carcinoma (NPC).

METHODS AND RESULTS

Tumour budding was investigated in 105 patients with NPC by immunohistochemistry for pan-cytokeratin (AE1/AE3). The intensity of budding correlated strongly with T classification (P=0.008), lymphatic invasion (P<0.001), vascular invasion (P=0.029), lymph node metastasis (P < 0.001), and clinical stage (P=0.010). Univariate analysis revealed that patients with high budding grade had poorer survival than those with low grade (P=0.002). Multivariate analysis showed that tumour budding was an independent predictor of survival (P=0.001). Furthermore, budding cells showed high-level expression of the cancer stem cell (CSC) marker ALDH1. Budding cells with high-level ALDH1 expression contributed to several aggressive behaviours and poor survival (P=0.000).

CONCLUSIONS

  We describe, for the first time, the presence of tumour budding and its correlation with aggressive tumour behaviour and poor patient survival in NPC. The degree of tumour budding could be a valuable predictive factor in NPC. In addition, we show, also for the first time, that budding cells in NPC might possess the invasive and metastatic properties of CSCs.

Oncologically safe distal resection margins in rectal cancer patients treated with chemoradiotherapy

INTRODUCTION

Although current guidelines recommend distal resection margins (DRM) of 2-5 cm in rectal cancer operation, smaller margins may be safe. We therefore assessed the impact of distal margins on outcomes in patients with rectal cancer treated with neoadjuvant chemoradiotherapy (CRT) followed by radical resection or resection followed by adjuvant CRT.

MATERIALS AND METHODS

This study involved 376 patients who underwent sphincter-saving resection for rectal adenocarcinoma and pre- or postoperative CRT between 2000 and 2006. DRMs were measured on pinned fixed specimens. We excluded patients who did not complete planned CRT and those with stage IV disease. A retrospective cross-sectional analysis was performed.

RESULTS

No significant differences in local recurrence (9.8 versus 7.3%; P = 0.324) and systemic recurrence (16.4 versus 18.7%; P = 0.731) were observed in patients with DRMs of ≤5 and >5 mm, respectively. Moreover, in each DRM category, there were no differences in local and systemic recurrence rates between patients who received pre- or postoperative CRT. DRM did not affect overall survival (P = 0.880) or 5-year survival rate (80.3 versus76.8%; P = 0.340).

CONCLUSION

A distal margin of at least 5 mm with negative resection margin on frozen section does not reduce oncological safety in rectal cancer patients who receive pre- or postoperative CRT.

Intra-tumoral budding in preoperative biopsy specimens predicts lymph node and distant metastasis in patients with colorectal cancer

Tumor budding, a histological hallmark of epithelial-mesenchymal transition in colorectal cancer, is a parameter of tumor progression and according to the International Union Against Cancer/American Joint Committee on Cancer an 'additional' prognostic factor. The current definition of tumor budding is reserved for the invasive tumor front of colorectal cancer (so called peri-tumoral budding), but tumor buds can also be observed in small preoperative biopsy specimens. Whereas the prognostic value of peri-tumoral budding assessed in resection specimens has found wide acceptance, the value of budding in preoperative biopsies, which normally do not encompass the invasive tumor margin and hence can be called intra-tumoral budding, has not been systematically investigated yet. Therefore, the aim of this study is to assess the predictive value of intra-tumoral budding for lymph node and distant metastasis in preoperative biopsies. Preoperative biopsy samples and consecutive resection specimens from 72 patients with pathological information on TNM stage, vascular, lymphatic and perineural invasion, and tumor border configuration were used to evaluate intra-tumoral budding and peri-tumoral budding. Both parameters were scored semiquantitatively as 'high' (detectable at low power magnification × 2.5) and 'low' (occasional budding at intermediate magnification × 10, difficult to find or absent). In biopsy samples high intra-tumoral budding was observed in 12/72 patients (17%) and associated with high peri-tumoral budding in the corresponding resection specimens (P=0.008). Additionally, there was a correlation between high intra-tumoral budding and lymph node metastasis (P=0.034), distant metastasis (P=0.007) and higher tumor grade (P=0.025). Peri-tumoral budding was associated with higher N stage (P=0.004), vascular (P=0.046) and lymphatic invasion (P=0.019) as well as with an infiltrating tumor border (P<0.001), reflecting the predictive power of peri-tumoral budding for tumor progression. High intra-tumoral budding in preoperative biopsy samples of colorectal cancer patients predicts high peri-tumoral budding at the invasive margin and lymph node metastasis in the corresponding resection specimens as well as distant metastasis.

The invasion and metastasis promotion role of CD97 small isoform in gastric carcinoma

CD97 is over-expressed in the majority of gastric adenocarcinomas and is associated with its dedifferentiation and aggressiveness. Our previous results demonstrated that out of three CD97 isoforms tested, only the small one was able to promote increased invasiveness in vitro. Based on these data we further aimed to investigate the role of CD97 small isoform in gastric cancer progression in vivo by employing the cells with a stable CD97 small isoform knock-down and an orthotopic gastric cancer mouse model. We could demonstrate that the knock down of CD97/EGF1,2,5, led to a significant decrease in the number of cells penetrating the gelatin coated membrane as compared with control cells. In the gastric cancer mouse model, both the hypodermic and the orthotopic yielded tumor masses of the CD97/EGF1,2,5kd group and were significantly smaller than the control. Metastatic tumor cell number in early metastatic regional lymph nodes on post-operative day 42 was distinctly decreased in the CD97/EGF1,2,5kd group as compared with the SGC-NS group, and was accompanied with the downregulation of CD44, VEGFR, CD31 and CD97. We concluded in this study that CD97 small isoform not only supported gastric cancer local growth, but also promoted metastatic spread in orthotopically implanted mouse model suggesting involvement of the CD97 small isoform in the preparation of (pre)metastatic niche.

The complex intratumoral heterogeneity of colon cancer highlighted by laser microdissection

AIMS

To evaluate the utility of laser microdissection in the comparison of phenotypes and genetic alterations between colon cancer and corresponding liver metastasis in the context of intratumoral heterogeneity.

METHODS

Immunohistochemistry was performed on a series of 11 patients surgically treated for colon adenocarcinoma with liver metastases, using antibodies directed against six mucins. Immunohistochemistry was completed by laser microdissection of tumor zones with particular phenotype, luminal zone and invasion front of colon tumors. Microdissected samples were compared on the basis of microsatellite instability and alterations of CTNNB1, KRAS, and TP53.

RESULTS

Our study demonstrated varying mucin expression within tumors, suggesting the existence of phenotypic intratumoral heterogeneity. A common immunohistochemical profile was observed in individual tumors between tumoral subpopulations and corresponding metastases. Nevertheless, the phenotypic characteristics were distinct from one patient to another. Laser microdissection underlined that phenotypic heterogeneity could rely on genotypic heterogeneity, and that some genetic alterations were common to microdissected samples from primary colon tumors and liver metastases.

CONCLUSION

We illustrated intratumoral heterogeneity of colon cancer using laser microdissection, in combination with immunohistochemical and genotypic tools. This intratumoral heterogeneity could represent a major issue in the search of prognostic biomarkers.

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.

Prognostic significance of tumor budding in gastrointestinal tumors

Tumor budding describes the presence of single tumor cells or small tumor cell clusters at the invasion front of carcinomas. It is currently thought to be the result of epithelial-mesenchymal transformation. Tumor budding can be appreciated histologically during routine evaluation of malignant polyps or surgical specimens of malignant tumors. Many studies have been published assessing cancers in all locations from the esophagus to the rectum, almost always reporting similar results. This seems especially remarkable as a generally accepted definition of how budding must be evaluated is still lacking. Regardless of the location, tumor budding generally is associated with nodal metastases and aggressive behavior, and it is mostly independent from other adverse factors. While the prognostic value of tumor budding is evident, especially in stage II colorectal cancers, it still has no therapeutic implications. This is owing to the heterogeneity of the performed studies and the lack of oncological studies, which are urgently needed.

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.

Increased epidermal growth factor receptor expression at the invasive margin is a negative prognostic factor in colorectal cancer

The receptor tyrosine kinase epidermal growth factor receptor (EGFR) is often expressed in solid malignant tumours, and the expression has been correlated to disease progression. Multiple new agents targeted against the EGFR have been developed during the last decade, but treatment selecting criteria are still not clear. This immunohistochemical study includes 386 colorectal cancer patients and focuses on EGFR expression variations within the tumour, comparing central parts to the invasive margin. Positive immunostaining for EGFR was evident in the central part in 176/386 (46%) of analyzed primary tumours. The invasive margin was positive in 222/386 (58%). A similar expression in both the central part and the invasive front was evident in 286/386 (74%). An increased score at the invasive margin compared to central parts (EGFR(i) ) was evident in 97/386 (25%) of the tumours. Moreover, the results show a significant survival disadvantage for the EGFR(i) group, both in potentially curatively resected colon cancer patients (n = 170, p = 0.01) and in potentially curatively resected colon and rectal cancer patients combined (n = 273, p = 0.013). Multivariate survival analysis adjusted for age, gender, bowel localisation, grade, stage and tumour type showed an increased risk of cancer death for EGFR(i) tumours (HR, 1.53; 95% CI, 1.04-2.23; p = 0.029). A significant correlation between EGFR expression at the invasive margin and the presence of budding was seen (p = 0.0001). This investigation of a large patient material implies that EGFR immunohistochemical analysis still has a role in risk evaluation of colorectal cancer patients.

Correlation between tumor budding and post-resection prognosis in patients with invasive squamous cell carcinoma of the thoracic esophagus

BACKGROUND

Tumor budding is defined as an isolated single cancer cell or a cluster of cancer cells composed of fewer than five cells at the invasive front of a tumor. The aim of the present study was to identify correlations between tumor budding and clinicopathological factors and their impact on postoperative prognosis in invasive squamous cell carcinoma of the thoracic esophagus.

METHODS

The subjects were 82 patients who underwent curative resection. The number of tumors showing budding was counted immunohistochemically based on positivity for cytokeratin (AE1/AE3) to distinguish cancer cells from inflammatory cells, and the patients were divided into low-grade and high-grade budding groups. High-grade budding was defined as ≥5 budding foci per field under a 20× objective lens.

RESULTS

One group of 36 patients (43.9%) and a second group of 46 patients (56.1%) were classified into the low-grade and high-grade budding groups, respectively. Patients in the high-grade budding group had significantly larger tumor size, deeper depth of invasion, more frequent lymphatic invasion and venous invasion, as well as more lymph node metastases, than those in the low-grade budding group. Disease-free and overall survivals were worse in the high-grade budding group than in the low-grade budding group (P<0.0001 and P=0.0002, respectively). Three of four patients who had tumor recurrence more than 5 years postoperatively belonged to the low-grade budding group.

CONCLUSIONS

Tumor budding appears to be an indicator of tumor growth and invasiveness. Patients with low-grade budding are likely to have a better prognosis than those with high-grade budding, but the tumor may recur in the late phase postoperatively in patients with low-grade budding.

Tumour budding correlates with local recurrence of rectal cancer

AIM

Predictive tools for local recurrence (LR) of rectal cancer are needed. This study assessed the predictive value of tumour budding detected by MNF-116 and laminin-5 γ2 chain (Ln-5 γ2).

METHOD

In a case-control study, the surgical specimens of 48 patients with LR after from primary resection of rectal carcinoma and 82 control patients matched for gender and preoperative radiation from a population of 1180 patients operated with total mesorectal excision were studied. The presence of budding was examined using immunohistochemistry with Ln-5 γ2 and pan-cytokeratin staining with MNF-116.

RESULTS

Tumour budding counts ranged from 0 to 106 buds (mean 43, median 38) for all patients. Significantly more tumours with more than 35 buds were seen in the LR than in the control group (67 vs 44%; P = 0.02). The spread of budding was also more extensive in the LR than in the control group (63 vs 49%, P = 0.03). In a multivariate analysis with tumour, node, metastasis stage, MNF-116-stained budding was an independent predictor of local failure (P = 0.02). The budding frequency was higher in irradiated tumours in comparison with tumours that had not received irradiation (mean 53 vs 38, P = 0.03). For Ln-5 γ2, more tumours with ≥ 10 buds were seen in the group with LR than among the control patients, but this difference was not statistically significant (73 vs 57%; P = 0.09). No additive value was found in the multivariate logistic regression model when Ln-5 γ2-stained budding frequency was added to MNF-116 and tumour, node, metastasis stage. The agreement between budding frequency determined by MNF-116 and Ln-5 γ2 was moderate, with a κ-coefficient of 0.34 (0.16-0.51).

CONCLUSION

Tumour budding determined by MNF-116 staining may serve as a predictive marker for LR in rectal cancer.

Predictive markers of colorectal cancer liver metastases

Liver metastases are the most common site of distant failure after curative resection of colorectal cancer and a source of significant cancer-related morbidity and mortality. Currently, imaging and conventional histopathologic features, such as T-stage and N-stage, are used by clinicians to inform prognosis and guide adjuvant treatment to reduce the risk of developing distant metastases. However, these tools only have a moderate ability to predict the development of liver metastases. Novel methods, including the detection of circulating tumor cells and carcinoembryonic antigens in serum, have been developed, and their prognostic and predictive characteristics have been assessed. In addition, several molecular and genetic markers in the primary tumor have been studied. Unfortunately, these studies are often small and their results have been mixed, yielding no consistent sets of externally validated predictors of colorectal liver metastases. For widespread clinical relevance, future tests need to be independently carried out on large independent patient samples.

Tumor budding and survival after potentially curative resection of node-positive colon cancer

PURPOSE

The aim of this study was to investigate the relationship between tumor budding and other pathology features and overall survival after resection of clinicopathological stage III colon cancer.

METHODS

The number of buds and other histopathological features were assessed in 477 patients who were operated on between 1971 and 2001, with follow-up to December 2006. Overall survival was analyzed using the Kaplan-Meier method and Cox regression.

RESULTS

The number of buds was dichotomized as low (0 to 8) vs high (>or=9). High budding was more common in men, in high-grade tumors, in the presence of venous invasion, and where the tumor had involved a free serosal surface, but budding was not associated with 8 other clinical and pathological features. The 5-year survival rate for patients with 0 to 8 buds was 51.0% (95% confidence interval, 44.9-55.1), whereas that for patients with 9 or more buds was 33.9% (95% confidence interval, 25.2-42.8). This association, however, disappeared after adjustment for other variables independently associated with survival (hazard ratio, 1.2; 95% confidence interval, 0.94-1.54; P = .139).

CONCLUSION

In stage III colon cancer, tumor budding did not provide additional independent prognostic information beyond that given by routine pathology reporting.