Venous invasion may predict lymph node metastasis in early rectal cancer

Routine elastin staining improves venous invasion detection in colorectal carcinoma

BACKGROUND

Colorectal carcinoma is the second most common cause of cancer-related deaths in North America. Invasion of tumor cells into lymphatic and blood vessels is an imperative step in the metastatic progression of colorectal carcinoma.

OBJECTIVES

This is a before-and-after study conducted by the Department of Pathology and Laboratory Medicine of Mount Sinai Medical Center of Florida to assess the impact on venous invasion (VI) detection by implementing routine elastin staining on all tumor-containing blocks per case, where feasible, in colorectal carcinoma (CRC) resection specimens.

METHODS

Clinicopathological parameters of CRC specimens were collected from January until December 2021 (n = 93) for the pre-implementation cohort and from January until December 2022 (n = 61) for the post-implementation cohort.

RESULTS

VI detection was significantly increased in the post-implementation cohort at a rate of 50.8 % compared to only 18.6 % in the pre-implementation cohort. The majority of VI identified in the pre-implementation cohort was extramural (61.5 %), whereas in the post-implementation cohort it was intramural (41.9 %). On univariate analysis, implementation of routine elastin stain was associated with strikingly increased VI detection rates (OR = 4.5, p-value < 0.001). On multivariate analysis, after adjusting for other clinicopathologic variables, elastin staining retained its independent statistically significant impact on VI detection (OR = 2.6, p-value = 0.034). Of note, there were no significant differences in the pre- and post-implementation cohorts in the frequency of nodal metastases, tumor extent, histologic grade, perineural invasion, T stage or M stage.

CONCLUSION

Based on our results and what has been published recently, we confirm an increase in the VI detection rate after implementing routine elastin staining on all tumor-containing blocks in CRC resection specimens.

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 ).

Vascular Enlargement as a Predictor of Nodal Involvement in Bladder Cancer

In bladder cancer (BC), the evaluation of lymph node (LN) involvement at preoperative imaging lacks specificity. Since neoangiogenesis is paired with lymphatic involvement, this study aims to evaluate the presence of perivesical venous ectasia as an indirect sign of LN involvement, together with other conventional CT findings. All the patients who underwent radical cystectomy (RC) for BC between January 2017 and December 2019 with available preoperative contrast-enhanced CT (CECT) within 1 month before surgery were included. Patients without available pathological reports (and pTNM stage) or who underwent neoadjuvant treatments and palliative RC were excluded. Two readers in blind assessed the nodal shape and hilum, the short axis, and the contrast enhancement of suspicious pelvic LNs, the Largest Venous Diameter (LVD) efferent to the lesion, and the extravesical tumor invasion. In total, 38 patients (33 males) were included: 17 pT2, 17 pT3, 4 pT4; pN+: 20/38. LN short axis > 5 mm, LN enhancement, and LVD > 3 mm were significantly correlated with N+ at pathology. LVD > 3 mm had a significantly higher sensitivity and specificity (≥90%, AUC = 0.949) and was an independent predictor (p = 0.0016).

Extramural vascular invasion as an independent prognostic marker in locally advanced rectal cancer: propensity score match pair analysis

BACKGROUND

In rectal cancers, presence of extramural vascular invasion on MRI (mrEMVI) is associated with poor survival. The independent influence of mrEMVI in the presence of other prognostic factors has not been previously analyzed using match pair analysis.

PATIENTS AND METHODS

Consecutive 92 patients having mrEMVI at presentation treated between January 2016 and December 2018 were matched with 92 patients (1:1) without mrEMVI. Matching parameters were T stage, mesorectal fascia involvement, and tumor differentiation. The presence and absence of mrEMVI were correlated to outcomes. An event was defined as locoregional failure or distant metastasis or poor response to chemoradiation rendering the rectal tumor as inoperable.

RESULTS

At 3 years, in the mrEMVI-positive cohort, 59% had an event and in the mrEMVI-negative cohort, 45% had an event (p = 0.026). Local control was 90.2% (12recurrences in 122 who underwent surgery), two recurrences in the mrEMVI-positive cohort and ten patients in the mrEMVI-negative cohort, which missed statistical significance (p = 0.06). Distant metastasis-free survival was significantly worse in the mrEMVI-positive cohort versus the mrEMVI-negative cohort (58.2% vs. 69.4%) (p = 0.022). Similarly, Overall survival was significantly inferior in mrEMVI-positive cohort compared to the mrEMVI-negative cohort (57% vs. 72.4%) (p = 0.02). The multivariate regression analysis confirmed the independent predictive value of mrEMVI.  CONCLUSION: Extramural vascular invasion detected through MRI is an independent risk factor for distant metastasis in the locally advanced carcinoma rectum. Aggressive treatment regimens like total neoadjuvant treatment should be considered in these cases pending randomized control studies.

Association Between Chemotherapy and Survival in T1 Colon Cancer With Lymph Node Metastasis: A Propensity-Score Matched Analysis

This study aimed to comprehensively examine the efficacy of chemotherapy in T1 colon cancer patients with lymph node metastasis.

Development of a Novel Prognostic Model for Predicting Lymph Node Metastasis in Early Colorectal Cancer: Analysis Based on the Surveillance, Epidemiology, and End Results Database

Background

Identification of a simplified prediction model for lymph node metastasis (LNM) for patients with early colorectal cancer (CRC) is urgently needed to determine treatment and follow-up strategies. Therefore, in this study, we aimed to develop an accurate predictive model for LNM in early CRC.

Methods

We analyzed data from the 2004-2016 Surveillance Epidemiology and End Results database to develop and validate prediction models for LNM. Seven models, namely, logistic regression, XGBoost, k-nearest neighbors, classification and regression trees model, support vector machines, neural network, and random forest (RF) models, were used.

Results

A total of 26,733 patients with a diagnosis of early CRC (T1) were analyzed. The models included 8 independent prognostic variables; age at diagnosis, sex, race, primary site, histologic type, tumor grade, and, tumor size. LNM was significantly more frequent in patients with larger tumors, women, younger patients, and patients with more poorly differentiated tumor. The RF model showed the best predictive performance in comparison to the other method, achieving an accuracy of 96.0%, a sensitivity of 99.7%, a specificity of 92.9%, and an area under the curve of 0.991. Tumor size is the most important features in predicting LNM in early CRC.

Conclusion

We established a simplified reproducible predictive model for LNM in early CRC that could be used to guide treatment decisions. These findings warrant further confirmation in large prospective clinical trials.

Risk factors for lymph node metastasis in early colon cancer

BACKGROUND

The aim of the study was to determine factors predicting lymph node metastasis in patients with T1 or T2 colon cancer.

METHODS

A total of 906 patients with T1 or T2 colon cancer who underwent colon resection with regional lymphadenectomy in a tertiary hospital, from January 2008 to December 2013, were analyzed. The prognostic factors for LN metastasis and the risk factors for survival were analyzed.

RESULTS

There were 728 patients (80.4%) without lymph node metastasis (LN-negative group) and 178 patients (19.6%) with lymph node metastasis (LN-positive group). Tumor invasion depth (P < 0.001), lymphatic invasion (P < 0.001), and perineural invasion (P = 0.008) were significantly different between the two groups. During the median follow-up period of 69 months, the 5-year disease-free survival rate was 98.6% for the LN-negative group and 92.8% for the LN-positive group (P ≤ 0.001). In multivariate analysis, influencing factors associated with disease-free survival rate were LN metastasis (P = 0.001) and perineural invasion (P = 0.040). Female, depth of tumor invasion (P = 0.001), and lymphatic invasion (P < 0.001) were significant independent predictive factors for lymph node metastasis in multivariate analysis.

CONCLUSION

Positive LN status predicted poor disease-free survival in patients with early cancer. This suggests that depth of tumor invasion ≥ sm2 and the presence of lymphatic invasion in early colon cancer provide useful information to determine which patients would benefit from radical surgery.

Evaluation of KRAS, NRAS and BRAF mutational status and microsatellite instability in early colorectal carcinomas invading the submucosa (pT1): towards an in-house molecular prognostication for pathologists?

AIM

We aimed to study the prognostic value of KRAS, NRAS, BRAF mutations and microsatellite stable (MSS)/instable (MSI) in the field of colorectal cancer invading the submucosa (ie, pT1 colorectal cancer (CRC)).

METHODS

We led a case-control study in tumour samples from 60 patients with pT1 CRC with (20 cases) and without (40 cases) metastatic evolution (5 years of follow-up) which were analysed for KRAS, NRAS, BRAF mutations (Idylla testing and next generation sequencing, NGS) and MSS/MSI status (Idylla testing and expression of mismatch repair (MMR) proteins using immunohistochemistry).

RESULTS

KRAS mutations were encountered in 11/20 (55%) cases and 21/40 (52.5%) controls (OR=1.11 (0.38 to 3.25), p=0.8548), NRAS mutations in 1/20 (5%) cases and 3/40 (7.5%) controls (OR=3.08 (0.62 to 15.39), p=0.1698) and BRAF mutations in 3/20 (15%) cases and 6/40 (15%) controls (OR=1.00 (0.22 to 4.5), p=1.00). A MSI status was diagnosed in 3/20 (15%) cases and 5/40 (12.5%) controls (OR=1.2353 (0.26 to 5.79), p=0.7885). Beyond the absence of significant association between the metastatic evolution and any of the studied molecular parameters, we observed a very good agreement between methods analysing KRAS, NRAS and BRAF mutations (Kappa value of 0.849 (0.748 to 0.95) between Idylla and NGS) and MSS/MSI (Idylla)-proficient MMR/deficient MMR (immunohistochemistry) status (Kappa value of 1.00).

CONCLUSION

Although being feasible using the fully automated Idylla method as well as NGS, the molecular testing of KRAS, NRAS, BRAF and MSS/MSI status does not seem useful for prognostic purpose in the field of pT1 CRC.

Histopathological factors help to predict lymph node metastases more efficiently than extra-nodal recurrences in submucosa invading pT1 colorectal cancer

The therapeutic management of patients with endoscopic resection of colorectal cancer invading the submucosa (i.e. pT1 CRC) depends on the balance between the risk of cancer relapse and the risk of surgery-related morbidity and mortality. The aim of our study was to report on the histopathological risk factors predicting lymph node metastases and recurrences in an exhaustive case series comprising every pT1 CRC (of adenocarcinoma subtype only) diagnosed in Finistère (France) during 5-years. For 312 patients with at least 46 months follow-up included in the digestive cancers registry database, histopathological factors required for risk stratification in pT1 CRC were reviewed. Patients were treated by endoscopic resection only (51 cases), surgery only (138 cases), endoscopic resection followed by surgery (102 cases) or transanal resection (21 cases). Lymph node metastases were diagnosed in 19 patients whereas 15 patients had an extra-nodal recurrence (7 local recurrences only, 4 distant metastases only and 4 combining local and distant recurrences). Four patients with distant metastases died of their cancer. Poor tumor differentiation, vascular invasion and high grade tumor budding on HES slides were notably identified as strong risk-factors of lymph node metastases but the prediction of extra-nodal recurrences (local, distant and sometimes fatal) was less obvious, albeit it was more frequent in patients treated by transanal resection than with other treatment strategies. Beyond good performances in predicting lymph node metastases and guiding therapeutic decision in patients with pT1 CRC, our study points that extra-nodal recurrence of cancer is more difficult to predict and requires further investigations.

Low expression of MUC2 is associated with longer disease-free survival in patients with colorectal carcinoma

BACKGROUND/AIM

The objective of this study was to investigate the relationship between MUC2 immunostaining and clinicopathological characteristics in a subset of colorectal carcinomas (CRCs).

MATERIALS AND METHODS

A total of 128 CRCs, 50 local nodal metastases, and 42 normal colonic mucosae were retrieved from the archives at the Department of Pathology at King Abdulaziz University, Jeddah, Saudi Arabia. Immunohistochemistry was performed using anti-MUC2 antibody. A cut-off of 25% of positive immunostaining was used to define low and high immunostaining. Statistical tests were used to determine the association of MUC2 with clinicopathological characteristics and survival.

RESULTS

MUC2 immunostaining was observed in 66.7% in normal colonic mucosa. Low MUC2 immunostaining was higher in primary CRC (P = 0.003) and nodal metastasis (80%) (P < 0.001). There was significant association of low MUC2 immunostaining in CRC with age group below 60 years (P = 0.05) and occurrence of lymphovascular invasion (P = 0.034). Other clinicopathological parameters were not correlated with MUC2 immunostaining. Regression analysis revealed that low MUC2 immunostaining was an independent predictor of lymphovascular invasion (P = 0.041). In the Kaplan-Meier survival analysis, there was a significant longer disease-free survival in patients with low MUC2 immunostaining (P = 0.045). However, there was no association between MUC2 immunostaining and overall survival (P = 0.601).

CONCLUSION

MUC2 immunostaining may have distinct clinical significance and provide valuable information and could be considered as an important independent prognostic factor while planning the adjuvant therapy in CRC. In future perspective, characterization of MUC2 immunostaining on a large number of cases and molecular studies may be needed.

Newly recognized extratumoral features of colorectal cancer challenge the current tumor-node-metastasis staging system

One of the most common malignant tumors in humans, colorectal cancer has been extensively studied during the past few decades. Staging colorectal cancer allows clinicians to obtain precise prognostic information and apply specific treatment procedures. Apart from remote metastases, the depth of tumor infiltration and lymph node involvement have traditionally been recognized as the most important factors predicting outcome. Variations in the molecular signature of colorectal cancer have also revealed differences in phenotypic aggressiveness and therapeutic response rates. This article presents a review of the extratumoral environment in colorectal surgery.

A predictive nomogram improved diagnostic accuracy and interobserver agreement of perirectal lymph nodes metastases in rectal cancer

Objective

To develop a predictive nomogram to improve the diagnostic accuracy and interobserver agreement of pre-therapeutic lymph nodes metastases in patients with rectal cancer.

Materials and Methods

An institutional database of 411 patients with rectal cancer was used to develop a nomogram to predict perirectal lymph nodes metastases. Patients' clinicopathological and MRI-assessed imaging variables were included in the multivariate logistic regression analysis. The model was externally validated and the performance was assessed by area under curve (AUC) of the receiver operator characteristics (ROC) curves. The interobserver agreement was measured between two independent radiologists.

Results

The diagnostic accuracy of the conventional MRI-assessed cN stage was 68%; 14.2% of the patients were over-staged and 17.8% of the patients were under-staged. A total of 35.1% of the patients had disagreed diagnosis for the cN stage between the two radiologists, with a kappa value of 0.295. A nomogram for predicting pathological lymph nodes metastases was successfully developed, with an AUC of 0.78 on the training data and 0.71 on the validation data. The predictors included in the nomogram were MRI cT stage, CRM involvement, preoperative CEA, tumor grade and lymph node size category. This nomogram yielded improved prediction in cN stage than the conventional MRI-based assessment.

Conclusions

By incorporating clinicopathological and MRI imaging features, we established a nomogram that improved the diagnostic accuracy and remarkably minimized the interobserver disagreement in predicting lymph nodes metastases in rectal cancers.

Patient gender as a factor associated with lymph node metastasis in T1 colorectal cancer: A systematic review and meta-analysis

Approximately 10% of patients with T1 colorectal cancer have lymph node metastases (LNM), requiring node dissection along with surgical resection. Patient gender was recently reported to affect the occurrence of LNM. The aim of the present study was to assess whether patient gender was predictive of LNM in T1 colorectal cancer. Public databases, including PubMed, EMBASE and the Cochrane Central Register of Controlled Trials were searched, using key terms related to 'T1 colorectal cancer' and 'lymph node'. All relevant studies reporting the adjusted odds ratio or risk ratio of LNM in relation to patient gender were included. The quality of the studies was classified according to the Quality in Prognostic Studies tool. A random-effects model was used and the quality of the evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. The initial database search identified 2,492 publications; of those, 36 studies reported unadjusted results. Of the 36 studies, 4 reported adjusted results and fulfilled the inclusion criteria for this meta-analysis: 3 studies were graded as having a moderate risk of bias, and 1 had a low risk of bias. The present meta-analysis demonstrated that female gender was associated with increased risk of LNM (risk ratio=2.45, 95% confidence interval: 1.03-3.88). The I² statistic was 0.901, classified as very low (+OOO) and was downgraded by the risk of bias, inconsistency and publication bias. In conclusion, female gender was found to be correlated with LNM in patients with T1 colorectal cancer.

Is the assessment of submucosal invasion still useful in the management of early rectal cancer? A study of 91 consecutive patients

AIM

The only studies on the prognosis of T1 tumours are old and investigate colic and rectal cancers. Very few studies use Kikuchi's classification (of dividing submucosa into three strata) to evaluate the depth of the submucosal invasion. This study aimed to assess the pathological risk factors for lymph node metastasis (LNM), and the pathological and oncological results of patients with early rectal cancer (ERC, pT1 tumour).

METHOD

Between 2000 and 2014, 91 consecutive patients undergoing surgery [primary total mesorectal excision (TME) or local excision (LE) alone, or LE followed by TME] for ERC were included.

RESULTS

Eighteen patients underwent LE, 22 underwent LE followed by TME and 51 underwent primary total TME. After TME (n = 73), 16 (23%) patients had LNM. The LNM rate was 15% for Sm1 tumours, 14% for Sm2 tumours and 30% for Sm3 tumours. In multivariate analysis, lymphovascular invasion (P = 0.027) and high tumour budding (P = 0.037) were the only independent factors predictive of LNM. The depth of submucosal invasion was not associated with an increased risk of LNM. After a mean follow up of 56 ± 46 months, 5-year overall survival, specific survival and disease-free survival were, respectively, 82%, 93% and 75%. No significant difference of survival was found according to the depth of submucosal invasion or to the surgical management.

CONCLUSION

Histological features seem to be stronger risk factors for LNM than depth of submucosal invasion. Considering the LNM rate, TME should be discussed after LE in terms of one of these pathological criteria.

Practice parameters for early colon cancer management: Italian Society of Colorectal Surgery (Società Italiana di Chirurgia Colo-Rettale; SICCR) guidelines

Early colon cancer (ECC) has been defined as a carcinoma with invasion limited to the submucosa regardless of lymph node status and according to the Royal College of Pathologists as TNM stage T1 NX M0. As the potential risk of lymph node metastasis ranges from 6 to 17% and the preoperative assessment of lymph node metastasis is not reliable, the management of ECC is still controversial, varying from endoscopic to radical resection. A meeting on recent advances on the management of colorectal polyps endorsed by the Italian Society of Colorectal Surgery (SICCR) took place in April 2014, in Genoa (Italy). Based on this material the SICCR decided to issue guidelines updating the evidence and to write a position statement paper in order to define the diagnostic and therapeutic strategy for ECC treatment in context of the Italian healthcare system.

Pre-operative predictive factors for intra-operative pathological lymph node metastasis in rectal cancers

BACKGROUND

A number of clinicopathologic factors have been found to be associated with pathological lymph node metastasis (pLNM) in rectal cancer; however, most of them can only be identified by expensive high resolution imaging or obtained after surgical treatment. Just like the Child-Turcotte-Pugh (CTP) and the model for end-stage liver disease (MELD) scores which have been widely used in clinical practice, our study was designed to assess the pre-operative factors which could be obtained easily to predict intra-operative pLNM in rectal cancer.

METHODS

A cohort of 469 patients who were treated at our hospital in the period from January 2003 to June 2011, and with a pathologically hospital discharge diagnosis of rectal cancer, were included. Clinical, laboratory and pathologic parameters were analyzed. A multivariate unconditional logistic regression model, areas under the curve (AUC), the Kaplan-Meier method (log-rank test) and the Cox regression model were used.

RESULTS

Of the 469 patients, 231 were diagnosed with pLNM (49.3%). Four variables were associated with pLNM by multivariate logistic analysis, age<60 yr (OR=1.819; 95% CI, 1.231-2.687; P=0.003), presence of abdominal pain or discomfort (OR=1.637; 95% CI, 1.052-2.547; P=0.029), absence of allergic history (OR=1.879; 95% CI, 1.041-3.392; P=0.036), and direct bilirubin ≥ 2.60 μmol/L (OR=1.540; 95% CI, 1.054-2.250; P=0.026). The combination of all 4 variables had the highest sensitivity (98.7%) for diagnostic performance. In addition, age<60 yr and direct bilirubin ≥ 2.60 μmol/L were found to be associated with prognosis.

CONCLUSION

Age, abdominal pain or discomfort, allergic history and direct bilirubin were associated with pLNM, which may be helpful for preoperative selection.

MRI-detected extramural vascular invasion is an independent prognostic factor for synchronous metastasis in patients with rectal cancer

OBJECTIVES

To determine whether magnetic resonance imaging (MRI)-detected extramural vascular invasion (EMVI) could predict synchronous distant metastases in rectal cancer.

METHODS

Patients who underwent rectal MRI between July 2011 and December 2012 were screened. This study included 447 patients with pathologically confirmed rectal adenocarcinoma who had undergone MRI without previous treatment. Distant metastases were recorded at the initial work-up and over a 6-month follow-up. Univariate/multivariate logistic regression models were used to determine the risk of metastasis. The diagnostic performance was calculated using pathologic lymphovascular invasion (LVI) as a gold standard.

RESULTS

Among 447 patients, 79 patients (17.7 %) were confirmed to have distant metastases. Three MRI features are significantly associated with a high risk of distant metastasis: positive EMVI (odds ratio 3.02), high T stage (odds ratio 2.10) and positive regional lymph node metastasis (odds ratio 6.01). EMVI in a large vessel (≥3 mm) had a higher risk for metastasis than EMVI in a small vessel (<3 mm). Sensitivity, specificity and accuracy of MRI-detected EMVI were 28.2 %, 94.0 % and 80.3 %, respectively.

CONCLUSIONS

MRI-detected EMVI is an independent risk factor for synchronous metastasis in rectal cancer. EMVI in large vessels is a stronger risk factor for distant metastasis than EMVI in small vessels.

KEY POINTS

• EMVI, LN metastasis and T staging on MRI are risk factors for metastasis. • EMVI in large vessels has greater risk for metastasis than in small vessels. • Regional LN metastasis on MRI has highest risk for predicting metastasis. • MR findings could be helpful for selecting patients at high risk for metastasis.

Is adjuvant radiotherapy warranted in resected pT1-2 node-positive rectal cancer?

Background

Stage T1-2 rectal cancers are unlikely to have lymph node metastases and neoadjuvant therapy is not routinely administered. Postoperative management is controversial if lymph node metastases are detected in the resected specimen. We studied the outcomes of patients with pT1-2 node-positive rectal cancer in order to determine whether adjuvant radiotherapy was beneficial.

Methods

We conducted a retrospective analysis of 284 patients with pathological T1-2 node-positive rectal cancer from a single institution. Outcomes, including local recurrence (LR), distant metastasis (DM), disease free survival (DFS) and overall survival (OS), were studied in patients with detailed TN staging and different adjuvant treatment modalities.

Results

The overall 5-year LR, DM, DFS and OS rates for all patients were 12.5%, 32.9%, 36.4% and 76.8%, respectively. Local control was inferior among patients who received no adjuvant therapy. Patients could be divided into three risk subsets: Low-risk, T1N1; Intermediate-risk, T2N1 and T1N2; and High-risk, T2N2. The 5-year LR rates were 5.3%, 9.8% and 26.4%, respectively (p = 0.005). In High-risk patients, addition of radiotherapy achieved a 5-year LR rate of 9.1%, compared 34.8% without radiotherapy.

Conclusions

In our study, we provide the detailed outcomes and preliminary survival analysis in a relatively infrequent subset of rectal cancer. Three risk subsets could be identified based on local control for pT1-2 node positive rectal cancer. Postoperative treatment needs to be individualized for patients with pT1-2 node-positive rectal cancer.

Systematic review and meta-analysis of histopathological factors influencing the risk of lymph node metastasis in early colorectal cancer

AIM

Lymph node (LN) metastases are present in up to 17% of early colorectal cancers (pT1). Identification of associated histopathological factors would enable counselling of patients regarding this risk.

METHOD

Pubmed and Embase were employed utilizing the terms 'early colorectal cancer', 'lymph node metastasis', 'submucosal invasion', 'lymphovascular invasion', 'tumour budding' and 'histological differentiation'. Analysis was performed using REVIEW MANAGER 5.1.

RESULTS

Twenty-three cohort studies including 4510 patients were analysed. There was a significantly higher risk of LN metastasis with a depth of submucosal invasion > 1 mm than with lesser degrees of penetration (OR 3.87, 95% CI 1.50-10.00, P = 0.005). Lymphovascular invasion was significantly associated with LN metastasis (OR 4.81, 95% CI 3.14-7.37, P < 0.00001). Poorly differentiated tumours had a higher risk of LN metastasis compared with well or moderately differentiated tumours (OR 5.60, 95% CI 2.90-10.82, P < 0.00001). Tumour budding was found to be significantly associated with LN metastasis (OR 7.74, 95% CI 4.47-13.39, P < 0.001).

CONCLUSION

Meta-analysis of the current literature demonstrates that in early colorectal cancer a depth of submucosal invasion by the primary tumour of > 1 mm, lymphovascular invasion, poor differentiation and tumour budding are significantly associated with LN metastasis.

Cell budding from normal appearing epithelia: a predictor of colorectal cancer metastasis?

Background: Colorectal carcinogenesis is believed to be a multi-stage process that originates with a localized adenoma, which linearly progresses to an intra-mucosal carcinoma, to an invasive lesion, and finally to metastatic cancer. This progression model is supported by tissue culture and animal model studies, but it is difficult to reconcile with several well-established observations, principally among these are that up to 25% of early stage (Stage I/II), node-negative colorectal cancer (CRC) develop distant metastasis, and that circulating CRC cells are undetectable in peripheral blood samples of up to 50% of patients with confirmed metastasis, but more than 30% of patients with no detectable metastasis exhibit such cells. The mechanism responsible for this diverse behavior is unknown, and there are no effective means to identify patients with pending, or who are at high risk for, developing metastatic CRC.

Novel findings: Our previous studies of human breast and prostate cancer have shown that cancer invasion arises from the convergence of a tissue injury, the innate immune response to that injury, and the presence of tumor stem cells within tumor capsules at the site of the injury. Focal degeneration of a capsule due to age or disease attracts lymphocyte infiltration that degrades the degenerating capsules resulting in the formation of a focal disruption in the capsule, which selectively favors proliferating or “budding” of the underlying tumor stem cells. Our recent studies suggest that lymphocyte infiltration also triggers metastasis by disrupting the intercellular junctions and surface adhesion molecules within the proliferating cell buds causing their dissociation. Then, lymphocytes and tumor cells are conjoined through membrane fusion to form tumor-lymphocyte chimeras (TLCs) that allows the tumor stem cell to avail itself of the lymphocyte's natural ability to migrate and breach cell barriers in order to intravasate and to travel to distant organs. Our most recent studies of human CRC have detected nearly identical focal capsule disruptions, lymphocyte infiltration, budding cells, and the formation of TLCs. Our studies have further shown that age- and type-matched node-positive and -negative CRC have a significantly different morphological and immunohistochemical profile and that the majority of lymphatic ducts with disseminated cells are located within the mucosa adjacent to morphologically normal appearing epithelial structures that express a stem cell-related marker.

New hypothesis: Based on these findings and the growth patterns of budding cells revealed by double immunohistochemistry, we further hypothesize that metastatic spread is an early event of carcinogenesis and that budding cells overlying focal capsule disruptions represent invasion- and metastasis-initiating cells that follow one of four pathways to progress: (1) to undergo extensive in situ proliferation leading to the formation of tumor nests that subsequently invade the submucosa, (2) to migrate with associated lymphocytes functioning as “seeds” to grow in new sites, (3) to migrate and intravasate into pre-existing vascular structures by forming TLCs, or (4) to intravasate into vascular structures that are generated by the budding cells themselves. We also propose that only node-positive cases harbor stem cells with the potential for multi-lineage differentiation and unique surface markers that permit intravasation.

Risk factors for lymph node metastasis in pT1 and pT2 rectal cancer: a single-institute experience in 943 patients and literature review

BACKGROUND

Local excision has become an alternative for radical resection in rectal cancer for selected patients. The purpose of this study was to assess the clinicopathologic factors determining lymph node metastasis (LNM) in patients with T1-2 rectal cancer.

METHODS

Between January 1995 and December 2009, a total of 943 patients with pT1 or pT2 rectal adenocarcinoma received radical resection at a single institution. Clinicopathologic factors were evaluated by univariate and multivariate analyses to identify risk factors for LNM.

RESULTS

A total of 943 patients (544 men and 399 women) treated for T1-2 rectal cancer were included in this study. LNM was found in 188 patients (19.9%). In multivariate analysis, lymphovascular invasion (LVI; P < 0.001, hazard ratio 11.472), poor differentiation (PD; P = 0.007, hazard ratio 3.218), and depth of invasion (presence of pT2; P = 0.032, hazard ratio 1.694) were significantly related to nodal involvement. The incidence for LNM lesions in the presence of LVI, PD, and pT2 was 68.8, 50.0, and 23.1%, respectively, while that for pT1 carcinomas with no LVI or PD was 7.5%.

CONCLUSIONS

LVI, PD, and pT2 are independent risk factors predicting LNM in pT1-2 rectal carcinoma.

Intramural and extramural vascular invasion in colorectal cancer: prognostic significance and quality of pathology reporting

BACKGROUND

Blood vessel invasion has been associated with poor outcome in colorectal cancer (CRC), whereas the prognostic impact of lymphatic invasion is less clear. The authors of this report evaluated venous and lymphatic invasion as potential prognostic indicators in patients with CRC focusing on lymph node-negative patients and compared routine and review pathology diagnoses.

METHODS

In total, 381 tumors from randomly selected patients were retrospectively reviewed. The presence of vascular invasion was related to disease-free and cancer-specific survival using the Kaplan-Meier method. For multivariable analysis, Cox proportional hazards regression models were performed.

RESULTS

Lymphatic invasion and venous invasion were observed in 126 patients (33%) and 87 patients (23%), respectively, and were associated significantly with tumor classification, lymph node status, American Joint Committee on Cancer/International Union Against Cancer (AJCC/UICC) disease stage, tumor differentiation, pattern of invasion, and extent of tumor budding. The detection of vascular invasion was related to the number of examined tissue blocks. Venous and lymphatic invasion proved to be significant prognostic variables in univariable and multivariable analyses. Extramural vascular involvement was of particular significance. When the analysis was restricted to patients with (AJCC/UICC) stage II disease, venous invasion, but not lymphatic invasion, was identified as an independent prognostic variable. Review pathology diagnoses differed significantly from routine diagnoses with respect to prognostic impact.

CONCLUSIONS

Venous and lymphatic invasion proved to be significant prognostic variables in patients with CRC. The detection of vascular invasion and, consequently, risk stratification of affected patients were related to the quality of pathology workup, ie, the number of examined tissue blocks. Observed differences between review and routine pathology diagnoses illustrated the need for high-quality pathology reporting and also for standardized quality control.

Lymphovascular or perineural invasion may predict lymph node metastasis in patients with T1 and T2 colorectal cancer

BACKGROUND

The aim of the study was to evaluate factors for predicting lymph node metastasis in patients who had T1 and T2 colorectal cancer.

METHODS

A total of 224 patients with T1 or T2 colorectal cancers who underwent radical surgery with regional lymphadenectomy from January 1999 to January 2008 were analyzed.

RESULTS

Predictive factors for lymph node metastasis and prognostic factors were analyzed. Tumor stage was classified as T1 in 69 (30.8%) and T2 in 155 (69.2%) of patients. The overall incidence of lymph node metastasis was 21.0% (14.5% for T1 cancer and 23.9% for T2 cancer; P = 0.112). The node positive and negative groups were similar with regard to patient demographics, except that the former contained a significantly higher number of lymphovascular invasion and perineural invasion cases. During the median follow-up period of 49 months, the 5-year overall and disease-free survival rates for patients without lymph node metastasis were 97.1% and 94.6%, which were significantly higher than the rates for those with lymph node metastasis (85.5%, P = 0.008, and 82.0%, P = 0.007, respectively). A multivariate analysis revealed that lymph node status was the only significant independent prognostic factor for both overall survival (P = 0.025) and disease-free survival (P = 0.040). Moreover, the presence of lymphovascular invasion (P < 0.001) or perineural invasion (P = 0.004) was an independent predictor for lymph node metastasis.

CONCLUSION

Lymph node metastasis was the most powerful predictor for poorer survival in patients with T1 or T2 colorectal cancer. For patients with positive lymphovascular or perineural invasion, radical surgery should be recommended because of a greater chance for lymph node metastasis.

Predictive factors of early relapse in UICC stage I-III colorectal cancer patients after curative resection

BACKGROUND AND OBJECTIVES

To predict the clinicopathologic factors for early relapse of UICC stage I-III colorectal cancer (CRC) patients undergoing curative resection and thus to identify a subgroup of patients who are at high risk for postoperative early relapse.

METHODS

Between January 2001 and June 2007, a total of 778 UICC stage I-III CRC patients who underwent a radical resection and regular follow-up were retrospectively analyzed. Of these 778 CRC patients, 521 colon cancer and 257 rectal cancer cases were analyzed, respectively, to determine the predictors of early relapse postoperatively. These 778 patients were followed-up intensively, and their outcomes were investigated retrospectively.

RESULTS

Out of 521 colon cancer patients, postoperative relapse after primary resection was found in 142 (27.3%) patients, and 77 (54.2%) of 142 recurrent colon cancer patients were classified as postoperative early relapse. Meanwhile, among 257 rectal cancer patients, postoperative relapse was found in 68 (26.5%) patients and 44 (64.7%) of 68 recurrent rectal cancer patients were identified as postoperative early relapse. Forty-nine (63.6%) of 77 early relapsed colon cancer patients were stage III, and likewise, 26 (59.1%) of 44 early relapsed rectal cancer patients were stage III. Univariately, postoperative early relapse of colon cancer patients was significantly correlated with the presence of vascular invasion (P < 0.001), perineural invasion (P < 0.001), high postoperative carcinoembryonic antigen (CEA) level (P = 0.001), and type of surgery (P = 0.016). Using a Cox proportional hazards analysis, the presence of vascular invasion (P = 0.033), perineural invasion (P = 0.005), and high postoperative CEA levels (P = 0.001) were demonstrated to be independent predictors of postoperative early relapse of colon cancer patients, while in rectal cancer patients, both vascular invasion (P = 0.039) and perineural invasion (P = 0.008) were statistically significant predictors of early relapse by univariate analysis. Using a Cox proportional hazards analysis, only perineural invasion (P = 0.043) was an independent factor. Early relapse cases had significant lower overall survival rates than non-early relapse cases either in colon cancer (P < 0.001) or in rectal cancer (P = 0.0091) patients.

CONCLUSIONS

This study suggests that vascular invasion, perineural invasion, and postoperative CEA level may be significant factors for postoperative early relapse of colon cancer; while only perineural invasion is considered to be a significant predictor in rectal cancer patients. Identification of these high-risk UICC stage I-III CRC patients of early relapse is important, and thus could help to define patients with this tumor entity for an enhanced follow-up and therapeutic program.

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.

Predicting factors of postoperative relapse in T2-4N0M0 colorectal cancer patients via harvesting a minimum of 12 lymph nodes

BACKGROUND AND AIM

The aim of this retrospective study was to determine which clinicopathological factors influenced the incidence of postoperative relapse and overall survival rates after radical resection of T(2-4)N(0)M(0) colorectal cancer (CRC) patients via harvesting a minimum of 12 lymph nodes.

MATERIALS AND METHODS

Between January 2001 and June 2006, a total of 342 T(2-4)N(0)M(0) CRC patients who underwent radical resection were retrospectively analyzed in Kaohsiung Medical University Hospital. Of these 342 patients, 155 were observed by harvesting a minimum of 12 lymph nodes. These 155 patients were followed up intensively, and their outcomes were investigated retrospectively.

RESULTS

Of 155 patients, 83 were men (53.5%) and 72 (46.5%) were women. The mean age was 65.5 +/- 11.1 years (range, 24-89 years). The median follow-up period was 49 months (range, 19-80 months). The present data showed invasive depth (P = 0.012), vascular invasion (P < 0.001), and perineural invasion (P = 0.009) as significantly prognostic factors for postoperative 5-year relapse rate by Kaplan-Meier analysis. Likewise, invasive depth (P = 0.013), vascular invasion (P < 0.001), and perineural invasion (P = 0.008) were significant factors for postoperative 5-year survival rate. Meanwhile, using a Cox proportional hazards analysis, depth of tumor invasion (P = 0.026) and vascular invasion (P = 0.001) were the independent predictors for postoperative relapse. Furthermore, the presence of vascular invasion was considerably correlated to the higher postoperative relapse rate and the poorer overall survival rates by survival analyses (P < 0.0001).

CONCLUSIONS

Besides the conventional depth of tumor invasion, this study highlights the potential for using vascular invasion as a means of identifying a subgroup of T(2-4)N(0)M(0) CRC patients with adequate lymph node harvest at higher risk who would potential benefit from adjuvant therapy after surgery.

Prognostic significance of depth of invasion, vascular invasion and numbers of lymph node retrievals in combination for patients with stage II colorectal cancer undergoing radical resection

BACKGROUND AND OBJECTIVES

To determine which aspects of tumor histology influenced the postoperative relapse and overall survival rates after radical resection of UICC stage II colorectal cancer (CRC).

METHODS

Data were collected on 259 patients with stage II CRC who underwent radical resection in Kaohsiung Medical University Hospital between January 2002 and December 2005.

RESULTS

A univariate analysis identified that the depth of invasion, the presence of vascular invasion, the presence of perineural invasion, and the number of examined lymph nodes were significant prognostic factors for postoperative relapse. A combination of depth, vascular invasion, and numbers of lymph node retrieval as predictors of postoperative relapse showed that the more predictors that are involved, the higher chance that postoperative relapse would occur. Furthermore, T4 depth of tumor invasion, the presence of vascular invasion, and the number of examined lymph nodes <12 were considerably correlated to the poorer overall survival rates by survival analyses.

CONCLUSIONS

This study has revealed that the depth of invasion, the presence of vascular invasion, and number of examined lymph nodes, may prominently affect the prognosis of stage II CRC patients after radical resection. The increasing risk of postoperative relapse is proportionate to numbers of these three parameters.

Histopathologic determinants of regional lymph node metastasis in early colorectal cancer

BACKGROUND

Early colorectal cancer (ECC) is curable by endoscopic local resection; however, 10% of patients with ECC exhibit lymph node (LN) metastasis. In the current study, accurate predictors for LN metastasis in patients with ECC were examined by using immunohistochemistry with the lymphatic endothelial hyaluronan receptor 1 (LYVE-1) antibody to discriminate between lymphatics and blood vessels.

METHODS

Colorectal tissue specimens obtained from 71 patients with ECC, including 28 patients with regional LN metastasis, were immunostained with antibodies against LYVE-1, beta-catenin, claudin-3, claudin-4, and cytokeratin. The significance of the histopathologic variables for LN metastasis in ECC was investigated on the basis of specific histopathologic parameters.

RESULTS

Lymphatic invasion confirmed by LYVE-1 immunohistochemistry was observed mainly in the submucosal area around the primary tumor and rarely was observed in the tumor. Expression patterns of beta-catenin, claudin-3, and claudin-4 in cancer cells at the invasive front were irrelevant to LN status. Tumor size, depth of invasion, histologic tumor type, budding formation, and lymphatic invasion were statistically significant to LN status in univariate analysis; however, only 2 factors--lymphatic invasion and budding formation at the invasive front-were independent predictors of LN metastasis in ECC.

CONCLUSIONS

LYVE-1 immunohistochemistry appeared to be a useful method for detecting lymphatics invaded by cancer cells, and detailed examination of the submucosa around the tumor may be important for predicting LN metastasis. When lymphatic invasion and budding formation are observed histopathologically in patients with ECC, additional therapy, such as adjuvant chemotherapy or a curative resection of the regional LN, may be required.

The Relationship Between MR Demonstration of Extramural Venous Invasion and Nodal Disease in Rectal Cancer

PURPOSE

To investigate the relationship between extramural venous invasion (EMVI) detected at T2-weighted MRI and nodal disease rectal cancer compared with histopathology.

MATERIALS AND METHODS

The MR imaging of 79 consecutive patients with rectal cancer who underwent primary rectal surgery without neoadjuvant treatment were reviewed. MR images were scored by an expert radiologist for the presence and degree of EMVI using a five point scale blinded to pathological findings. Receiver operating characteristic curve analyses were performed to determine the sensitivity and specificity of MRI scoring in predicting EMVI and nodal disease at histopathology.

RESULTS

Compared with histology, an MR score of >2 was found to have 100% sensitivity (95% CI: 77%-100%) and 89% specificity (95% CI: 79%-96%) in identifying EMVI involving veins >3 mm in diameter. An EMVI score of >2 was had a sensitivity of 56% (95% CI: 30%-80%) and specificity of 81% (95% CI: 69%-90%) for identifying patients with stage N2 disease.

CONCLUSIONS

EMVI score of >2 on T2-weighted MR imaging has a high sensitivity and specificity for histopathologically proven extramural venous invasion involving venules ≥3 mm in diameter. However, EMVI scores have only moderate sensitivity in the predicting nodal involvement.

Accurate staging, selective preoperative therapy and optimal surgery improves outcome in rectal cancer: a review of the recent evidence

OBJECTIVE

The current optimal management of locally advanced rectal cancer has evolved from surgical excision followed by postoperative therapy in patients with involved margins, to an increasing use of a preoperative strategy to 'down-stage and/or down-size' the tumour. This treatment strategy is based on the relationship of the tumour to the mesorectal fascia, the optimal surgical circumferential resection margin that can be achieved by total mesorectal excision. We have reviewed the recent evidence for this strategy.

METHOD

An electronic literature search using PubMed identified articles on the subject of rectal cancer between January 2000 and December 2005. The search was limited to English language publications with secondary references obtained from key articles. Articles published in high impact factor journals formed the basis of the review, together with articles related to national programmes on the management of rectal cancer. This does lead to a selection bias, particularly as the articles identified had a European bias.

CONCLUSION

The UK NHS Cancer Plan has outlined the basis for the multidisciplinary team (MDT) management of rectal cancer. Advances in preoperative assessment through accurate staging and the recognition of the importance of the relationship of the tumour to the mesorectal fascia has allowed the selection of patients for a preoperative strategy to down-size/down-stage the tumour if this fascial layer is involved or threatened. Improvements in the quality of surgical resection through the acceptance of the principle of total mesorectal excision have ensured that optimal surgery remains the cornerstone to successful treatment. Further refinements of the MDT process strive to improve outcome. Accurate radiological staging, optimal surgery and detailed histopathological assessment together with consideration of a preoperative neoadjuvant strategy should now form the basis for current treatment and future research in rectal cancer.

Prognostic significance of immunohistochemically detected blood and lymphatic vessel invasion in colorectal carcinoma: its impact on prognosis

BACKGROUND

The prognostic significance of blood vessel invasion (BVI) and lymphatic vessel invasion (LVI) is unclear. Because of the absence of specific markers for venous and lymphatic vessels, earlier studies could not reliably distinguish between BVI and LVI.

METHODS

By immunostaining for podoplanin and CD34 antigen, we retrospectively investigated LVI and BVI in 419 tissue specimens of colorectal carcinoma. We performed univariate and multivariate analysis of the clinicopathologic features, frequency of recurrence, and outcome of patients with or without LVI and BVI.

RESULTS

The use of hematoxylin and eosin (H&E) staining to identify BVI and LVI yielded a false positive rate of 9.1% and false negative rate of 12.6%. The incidence of BVI was significantly higher among tumors with LVI than tumors without LVI (P <.001). In logistic multivariate analysis, only LVI (P < .001) was associated with lymph node metastasis and BVI (P = .015) was associated with distant recurrence. Calculating the prognostic relevance, both two invasion types correlated with decreased survival in univariate analysis (both P <.001). In multivariate analysis, BVI (P =.024), lymph node status (P =.003) and tumor stage (P <.001) remained statistically significant factors for survival.

CONCLUSIONS

Our results suggest that immunohistologic evaluation of BVI and LVI could be useful in colorectal carcinoma indicating the risk of lymph node metastasis and recurrence, thereby contributing to prognostic evaluation.

The influence of histopathologic criteria on the long-term prognosis of locally excised pT1 rectal carcinomas: results of local excision (transanal endoscopic microsurgery) and immediate reoperation

PURPOSE

Local excision of early rectal cancer is a controversial issue, which is in part because of differences in the evaluation of histopathologic criteria. This prospective study was designed to determine prognostic factors for recurrences and the need for reoperation.

METHODS

In 105 of 118 patients with pT1 carcinomas and local excision, results of recurrence rates and ten-year cancer-free survival were studied separately according to different histologic criteria (R0, R1, Rx, R < or = 1 mm, high-/low-risk situation), tumor localization (anterior, posterior, lateral wall and third of rectum), size, and degree of resection (full-thickness/partial wall). Patients were grouped into local excision (n = 89) and local excision followed by reoperation (n = 21). Risk classification was performed by division into "low-risk" carcinomas after local R0-resection (Group A) and unfavorable histologic results after local resection (R1, Rx, R < or = 1 mm, high-risk situation; Group B).

RESULTS

Local recurrence rates after local R0-resection of low-risk carcinomas were 6 percent, whereas patients in Group B with local resection were 39 percent. The recurrence risk in those patients was significantly reduced to 6 percent by reoperation (P = 0.015). In addition, ten-year, cancer-free survival was 93 percent in Group B after reoperation compared with 89 percent in patients of Group A after local excision alone.

CONCLUSIONS

Local R0-resection in cases with low-risk pT1 carcinomas represents an oncologically adequate therapy, which results in similar survival rates compared with primary radical surgery of pT1N0M0 rectal carcinomas. High recurrence rates are observed in tumors with unfavorable histologic result (Group B) requiring further treatment. In these cases immediate reoperation reduces the recurrence rate to 6 percent.

Location of early colorectal cancers at fold-top may reduce the risk of lymph node metastasis

PURPOSE

This study was designed to look for significant correlations between location of early colorectal cancer, distance from muscularis mucosae to muscularis propria, and the frequency of lymph node metastasis.

METHODS

A total of 166 early colorectal cancers, including 67 surgically resected lesions, were evaluated. The cancers were divided into two groups: metastatic and nonmetastatic. Cancer lesions were further subtyped at the fold-top or fold-bottom. Macroscopic classifications and histology were performed. Absolute invasive depth and distance from muscularis mucosae to muscularis propria was measured. Multivariate analysis was used to assess relationships among the variables.

RESULTS

The percentage of polypoid cancer lesions at fold-bottom was higher than at fold-top (74.5 vs. 51.8 percent), whereas flat-type cancer lesions at fold-bottom occurred less often than at fold-top (8.2 vs. 30.4 percent). Logistic regression showed that deep absolute invasive depth, lymphatic and vessel invasion, and cancer location (at fold-bottom) were the significant risk factors for early colorectal cancers leading to lymph-node metastasis. The distance from muscularis mucosae to muscularis propria with lymph-node metastasis (1,396.7 +/- 728.4 microm) was shorter than without lymph-node metastasis (3,533.9 +/- 2,507.8 microm; P < 0.01). Multivariate analysis showed that distance from muscularis mucosae to muscularis propria was a statistically significant factor for early colorectal cancers leading to lymph node metastasis (P = 0.0054).

CONCLUSIONS

We conclude that early colorectal cancers at the fold-top or with a long distance from muscularis mucosae to muscularis propria have less tendency to metastasize to lymph nodes. Clinically, these results provide evidence of a new indicator of endoscopic mucosal resection for early colorectal cancers at the fold-top.

Surgical Treatment of Rectal Cancer: Local Resection

Local treatment of rectal cancer aims to decrease the morbidity and the functional sequela associated with radical surgery without compromising local tumor control and long-term survival. Local excision is associated with a higher rate of local recurrence compared with radical surgery, and salvage radical surgery cannot guarantee equivalent long-term survival compared with radical surgery as the primary form of therapy. Therefore, strict criteria for patient selection are critical for local excision to be successful. Selecting the optimal therapy for an individual patient with rectal cancer is crucial and requires consideration of both tumor and patient characteristics. Endorectal ultrasonography is essential for the accurate assessment of rectal wall invasion and nodal metastasis. Only patients with well- or moderately differentiated T1 tumors without blood vessel or lymphatic vessel invasion are candidates for curative local excision as the only form of treatment. Tumors penetrating the muscularis propria should not be treated by local excision alone. These patients can be asked to participate in a trial of chemoradiation followed by local excision. Otherwise, they should undergo radical surgery. The tumor should be removed by full-thickness local excision with an adequate normal margin for pathologic evaluation. Final decisions regarding the treatment strategy should be based on the pathology of the surgical specimen. Intense, close follow-up is critical for early diagnosis of local recurrences as many of them may be surgically salvaged by radical resection. Local treatment can also be used for palliation of patients with histological unfavorable or advanced tumors, and those who are medically unfit for radical surgery.

Prediction of lymph node metastasis in colorectal carcinoma by expressionof chemokine receptor CCR7

Chemokine receptors are known to regulate homing of lymphocytes into secondary lymphoid organs and may also be involved in the lymphatic spread of solid tumors. Therefore, the assessment of chemokine receptor expression on colorectal carcinomas could potentially improve the prediction of lymph node spread. This is of great importance for the selection of patients for local therapy without the need for concomitant lymphatic dissection. Currently, only 5% of all patients can be selected for this desirable treatment option by established prognosticators. In a retrospective study, expression levels of the chemokine receptors CCR7, CXCR4 and CXCR5 were determined by immunohistochemistry on paraffin-embedded specimens of 99 colorectal carcinomas, which were curatively operated on, comprising all stages of the disease. Receptor expressions (absent vs. positive) from the overall tumor (OT) and from the invasion front (IF) including further prognosticators were correlated with lymph node status by uni- and multivariate analysis. Data were also correlated with synchronous distant metastases and overall survival. Median follow-up was 64 months. In univariate analysis, lymph node status correlated significantly with lymphovascular invasion, the expression of CCR7 IF, CCR7 OT, CXCR4 IF and CXCR4 OT, as well as pT category. Multivariate analysis revealed a significant correlation of lymph node status with lymphovascular invasion and CCR7 IF expression level. Most interestingly, CCR7 IF expression was significantly linked to decreased survival. CCR7 plays an important role in the mechanism of lymph node spread in colorectal carcinoma. Evaluation of the chemokine receptor expression profile seems to be appropriate to improve the selection of patients suited for local treatment and might constitute targets for nonsurgical therapy.