Tumor Deposits in Colorectal Cancer: Improving the Value of Modern Staging-A Systematic Review and Meta-Analysis

Interobserver variation in the classification of tumor deposits in rectal cancer-is the use of histopathological characteristics the way to go?

The focus on lymph node metastases (LNM) as the most important prognostic marker in colorectal cancer (CRC) has been challenged by the finding that other types of locoregional spread, including tumor deposits (TDs), extramural venous invasion (EMVI), and perineural invasion (PNI), also have significant impact. However, there are concerns about interobserver variation when differentiating between these features. Therefore, this study analyzed interobserver agreement between pathologists when assessing routine tumor nodules based on TNM 8. Electronic slides of 50 tumor nodules that were not treated with neoadjuvant therapy were reviewed by 8 gastrointestinal pathologists. They were asked to classify each nodule as TD, LNM, EMVI, or PNI, and to list which histological discriminatory features were present. There was overall agreement of 73.5% (κ 0.38, 95%-CI 0.33–0.43) if a nodal versus non-nodal classification was used, and 52.2% (κ 0.27, 95%-CI 0.23–0.31) if EMVI and PNI were classified separately. The interobserver agreement varied significantly between discriminatory features from κ 0.64 (95%-CI 0.58–0.70) for roundness to κ 0.26 (95%-CI 0.12–0.41) for a lone arteriole sign, and the presence of discriminatory features did not always correlate with the final classification. Since extranodal pathways of spread are prognostically relevant, classification of tumor nodules is important. There is currently no evidence for the prognostic relevance of the origin of TD, and although some histopathological characteristics showed good interobserver agreement, these are often non-specific. To optimize interobserver agreement, we recommend a binary classification of nodal versus extranodal tumor nodules which is based on prognostic evidence and yields good overall agreement.

Combining tumor deposits with the number of lymph node metastases to improve the prognostic accuracy in stage III colon cancer: a post hoc analysis of the CALGB/SWOG 80702 phase III study (Alliance)☆

BACKGROUND

In colon cancer, tumor deposits (TD) are considered in assigning prognosis and staging only in the absence of lymph node metastasis (i.e. stage III pN1c tumors). We aimed to evaluate the prognostic value of the presence and the number of TD in patients with stage III, node-positive colon cancer.

PATIENTS AND METHODS

All participants from the CALGB/SWOG 80702 phase III trial were included in this post hoc analysis. Pathology reports were reviewed for the presence and the number of TD, lymphovascular and perineural invasion. Associations with disease-free survival (DFS) and overall survival (OS) were evaluated by multivariable Cox models adjusting for sex, treatment arm, T-stage, N-stage, lymphovascular invasion, perineural invasion and lymph node ratio.

RESULTS

Overall, 2028 patients were included with 524 (26%) TD-positive and 1504 (74%) TD-negative tumors. Of the TD-positive patients, 80 (15.4%) were node negative (i.e. pN1c), 239 (46.1%) were pN1a/b (<4 positive lymph nodes) and 200 (38.5%) were pN2 (≥4 positive lymph nodes). The presence of TD was associated with poorer DFS [adjusted hazard ratio (aHR) = 1.63, 95% CI 1.33-1.98] and OS (aHR = 1.59, 95% CI 1.24-2.04). The negative effect of TD was observed for both pN1a/b and pN2 groups. Among TD-positive patients, the number of TD had a linear negative effect on DFS and OS. Combining TD and the number of lymph node metastases, 104 of 1470 (7.1%) pN1 patients were re-staged as pN2, with worse outcomes than patients confirmed as pN1 (3-year DFS rate: 65.4% versus 80.5%, P = 0.0003; 5-year OS rate: 87.9% versus 69.1%, P = <0.0001). DFS was not different between patients re-staged as pN2 and those initially staged as pN2 (3-year DFS rate: 65.4% versus 62.3%, P = 0.4895).

CONCLUSION

Combining the number of TD and the number of lymph node metastases improved the prognostication accuracy of tumor-node-metastasis (TNM) staging.

Endoscopic Ultrasound Elastography in the Assessment of Rectal Tumors: How Well Does It Work in Clinical Practice?

Endorectal ultrasound applications in the evaluation of rectal tumors could be a useful tool in achieving proper staging of rectal cancer. The purpose of this study was to compare the efficacy of rectal tumor staging by flexible endoscopic ultrasound (EUS) with real-time elastography (RTE) using the gold standard post-surgery histological analysis of the resected tissue as the control. The second aim of our research was to establish cutoff values for the EUS-RTE strain ratio corresponding to stages by independently comparing the stiffness values obtained with histology and EUS-RTE staging in order to minimize observation bias. We evaluated the records of 130 patients with a rectal tumor confirmed by biopsy. EUS was used in 70 patients, EUS-RTE-in the other 60. We found no statistically significant differences in staging accuracy when comparing EUS to EUS-RTE. Through a correspondence method between staging assessment and the EUS-RTE stain ratio, we identified cutoff intervals for T2, T3, and T4 staging that were nonoverlapping and proved to be statistically significant in terms of EUS-RTE values (significantly different ascending values from one interval to the other). We found that EUS-RTE offers slightly better, although not statistically significant sensitivity and specificity for T and N stage predictions compared to 2D EUS. Our results showed that EUS-RTE offers slightly higher sensitivity and specificity compared to EUS. Reliable cutoff intervals were found for strain rate elastography, previously available only for shear wave elastography (SWE) which is currently unavailable on any EUS system. Thus, these commonly available EUS-RTE systems can serve as a complementary tool in the staging of rectal tumors.

Smooth muscular layer: A new helpful criterion to reclassify tumor deposits into metastatic lymph nodes in patients with colo-rectal adenocarcinoma

CONTEXT

The origin of tumor deposit in colorectal cancer is still unknown, and currently there is no single morphological feature to distinguish a metastatic lymph node from a tumor deposit. Histologically, the normal lymph node capsule and trabeculae contain a smooth muscular layer, which when present in extramural deposits would strongly suggest their lymph node origin.

OBJECTIVE

We analyze the value of the smooth muscular layer criterion in reclassifying tumor deposit into metastatic lymph node.

DESIGN

A total of 458 colo-rectal carcinomas surgical specimens treated or not by neoadjuvant (radio)chemotherapy were retrospectively included. Harvested tumor deposits were analyzed by Hematoxylin and Eosin and elastin staining on 10 consecutive serial sections and by α- smooth muscle actin immunostaining.

RESULTS

A total of 129 tumor deposits were identified. 77 (60%) tumor deposits were reclassified into metastatic lymph node, of which 63 (49%) presented a smooth muscular layer on the initial Hematein Eosin staining and/or after serial tissue sections, confirmed by positive α-smooth muscle actin immunostaining in 43 out of 45 cases (90%). Fourteen (18%) additional tumor deposits were reclassified into metastatic lymph node by the appearance of lymphoid tissue after serial sections.

CONCLUSIONS

The presence of a smooth muscular layer in a presumable tumor deposit is helpful in pointing out its lymph node origin in patients with colo-rectal carcinomas. This criterion could improve the inter-observer agreement of tumor deposit identification, allowing accurate nodal staging and better assessment of patient's prognosis.

Comparative analysis of clonal evolution among patients with right- and left-sided colon and rectal cancer

Tumor multiregion sequencing reveals intratumor heterogeneity (ITH) and clonal evolution playing a key role in tumor progression and metastases. Large-scale high-depth multiregional sequencing of colorectal cancer, comparative analysis among patients with right-sided colon cancer (RCC), left-sided colon cancer (LCC), and rectal cancer (RC), as well as the study of lymph node metastasis (LN) with extranodal tumor deposits (ENTDs) from evolutionary perspective remain weakly explored. Here, we recruited 68 patients with RCC (18), LCC (20), and RC (30). We performed high-depth whole-exome sequencing of 206 tumor regions including 176 primary tumors, 19 LN, and 11 ENTD samples. Our results showed ITH with a Darwinian pattern of evolution and the evolution pattern of LCC and RC was more complex and divergent than RCC. Genetic and evolutionary evidences found that both LN and ENTD originated from different clones. Moreover, ENTD was a distinct entity from LN and evolved later.

Histopathological diagnosis of tumour deposits in colorectal cancer: a Delphi consensus study

AIMS

Tumour deposits (TDs) are an important prognostic marker in colorectal cancer. However, the classification, and inclusion in staging, of TDs has changed significantly in each tumour-node-metastasis (TNM) edition since their initial description in TNM-5, and terminology remains controversial. Expert consensus is needed to guide the future direction of precision staging.

METHODS AND RESULTS

A modified Delphi consensus process was used. Statements were formulated and sent to participants as an online survey. Participants were asked to rate their agreement with each statement on a five-point Likert scale and also to suggest additional statements for discussion. These responses were circulated together with anonymised comments, and statements were modified prior to carrying out a second online round. Consensus was set at 70%. Overall, 32 statements reached consensus. There were concerns that TDs were currently incorrectly placed in the TNM system and that their prognostic importance was being underestimated. There were concerns regarding interobserver variation and it was felt that a clearer, more reproducible definition of TDs was needed.

CONCLUSIONS

Our main recommendations are that the number of TDs should be recorded even if lymph node metastases (LNMs) are also present and that nodules with evidence of origin [extramural venous invasion (EMVI), perineural invasion (PNI), lymphatic invasion (LI)] should still be categorised as TDs and not excluded, as TNM-8 specifies. Whether TDs should continue to be included in the N category at all is controversial, and did not achieve consensus; however, participants agreed that TDs are prognostically worse than LNMs and the N1c category is suboptimal, as it does not reflect this.

Radiomics Based on T2-Weighted Imaging and Apparent Diffusion Coefficient Images for Preoperative Evaluation of Lymph Node Metastasis in Rectal Cancer Patients

Purpose

To develop and validate a radiomics nomogram based on T2-weighted imaging (T2WI) and apparent diffusion coefficient (ADC) features for the preoperative prediction of lymph node (LN) metastasis in rectal cancer patients.

Materials and Methods

One hundred and sixty-two patients with rectal cancer confirmed by pathology were retrospectively analyzed, who underwent T2WI and DWI sequences. The data sets were divided into training (n = 97) and validation (n = 65) cohorts. For each case, a total of 2,752 radiomic features were extracted from T2WI, and ADC images derived from diffusion-weighted imaging. A two-sample t-test was used for prefiltering. The least absolute shrinkage selection operator method was used for feature selection. Three radiomics scores (rad-scores) (rad-score 1 for T2WI, rad-score 2 for ADC, and rad-score 3 for the combination of both) were calculated using the support vector machine classifier. Multivariable logistic regression analysis was then used to construct a radiomics nomogram combining rad-score 3 and independent risk factors. The performances of three rad-scores and the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC). Decision curve analysis (DCA) was used to assess the clinical usefulness of the radiomics nomogram.

Results

The AUCs of the rad-score 1 and rad-score 2 were 0.805, 0.749 and 0.828, 0.770 in the training and validation cohorts, respectively. The rad-score 3 achieved an AUC of 0.879 in the training cohort and an AUC of 0.822 in the validation cohort. The radiomics nomogram, incorporating the rad-score 3, age, and LN size, showed good discrimination with the AUC of 0.937 for the training cohort and 0.884 for the validation cohort. DCA confirmed that the radiomics nomogram had clinical utility.

Conclusions

The radiomics nomogram, incorporating rad-score based on features from the T2WI and ADC images, and clinical factors, has favorable predictive performance for preoperative prediction of LN metastasis in patients with rectal cancer.

Lymph node metastasis is strongly associated with lung metastasis as the first recurrence site in colorectal cancer

BACKGROUND

The lymphatic system is known to be the primary pathway of metastasis for colorectal cancer. However, beyond regional lymph node metastases, little is known about the pathway of lymphatic metastases and the differences in the recurrence site risk. The aim of this study was to clarify the relationship between lymph node metastasis and the first recurrence site in colorectal cancer.

METHODS

Patients with colorectal cancer who underwent curative resection in our institution between January 2003 and December 2016 were included in this analysis. The relationship between the first recurrence site and clinicopathological factors was analyzed by the Cox regression model and competing risk regression model.

RESULTS

In total, 1,249 patients with colorectal cancer were included in this analysis. We found that the stages of lymph node metastases (N0 vs N1: P = .008, N0 vs N2a: P < .001, N0 vs N2b: P < .001) were significantly associated with lung metastasis in the multivariate analysis. Furthermore, in the competing risk analysis, the stages of lymph node metastases were significantly correlated with lung metastasis (N0 vs N1: P = .002, N0 vs N2a: P < .001, N0 vs N2b: P < .001) but were not correlated with other recurrence sites.

CONCLUSION

The severity of lymph node involvement had a strong correlation with lung metastases in patients with colorectal cancer.

Prognostic importance of circumferential resection margin in the era of evolving surgical and multidisciplinary treatment of rectal cancer: A systematic review and meta-analysis

BACKGROUND

Circumferential resection margin is considered an important prognostic parameter after rectal cancer surgery, but its impact might have changed because of improved surgical quality and tailored multimodality treatment. The aim of this systematic review was to determine the prognostic importance of circumferential resection margin involvement based on the most recent literature.

METHODS

A systematic literature search of MEDLINE, Embase, and the Cochrane Library was performed for studies published between January 2006 and May 2019. Studies were included if 3- or 5-year oncological outcomes were reported depending on circumferential resection margin status. Outcome parameters were local recurrence, overall survival, disease-free survival, and distant metastasis rate. The Newcastle Ottawa Scale and Jadad score were used for quality assessment of the studies. Meta-analysis was performed using a random effects model and reported as a pooled odds ratio or hazard ratio with 95% confidence interval.

RESULTS

Seventy-five studies were included, comprising a total of 85,048 rectal cancer patients. Significant associations between circumferential resection margin involvement and all long-term outcome parameters were uniformly found, with varying odds ratios and hazard ratios depending on circumferential resection margin definition (<1 mm, ≤1 mm, otherwise), neoadjuvant treatment, study period, and geographical origin of the studies.

CONCLUSION

Circumferential resection margin involvement has remained an independent, poor prognostic factor for local recurrence and survival in most recent literature, indicating that circumferential resection margin status can still be used as a short-term surrogate endpoint.

Development and validation of a novel prognostic nomogram including tumor deposits could better predict survival for colorectal cancer: a population-based study

Background

The number of tumor deposits (TDs) in colorectal cancer (CRC) prognosis remains debated. We evaluated whether the number of TDs affects prognosis in stage III CRC patients.

Methods

Univariate and multivariate analyses were performed with Cox proportional hazards models. The Kaplan-Meier method was used to estimate survival curves. The best cutoff was determined using X-Tile. Patients were 1:1 randomly divided into the training set or the testing set. Prognostic nomogram was established for stage III CRC patients. Concordance index (C-index) and calibration plot were used to assess Nomogram models.

Results

In total, 18,043 (84.69%) CRC patients without TDs and 3,263 (15.31%) patients with TDs were analyzed. Patients with TDs had significantly worse cancer-specific survival (CSS) rates (P<0.001). The number of TDs is an independent factor for the CSS of stage III CRC patients. CSS nomogram of stage III CRC patients was constructed based on race, age at diagnosis, tumor location, histological grade, pathological type, T, N, TDs, chemotherapy. In training set, C-index for CSS nomogram 0.762 (95% CI: 0.752–0.772). In testing set, the C-index for CSS nomogram 0.759 (95% CI: 0.749–0.768). The quality of calibration plots of nomogram models was high.

Conclusions

The presence of TDs is an independent risk prognostic factor for stage III CRC. The number of TDs had a high proportion of prognostic impact.

High-resolution MRI-based radiomics analysis to predict lymph node metastasis and tumor deposits respectively in rectal cancer

PURPOSE

To establish and validate two predictive radiomics models for preoperative prediction of lymph node metastases (LNMs) and tumor deposits (TDs) respectively in rectal cancer (RC) patients.

METHODS

A total of 139 RC patients (98 in the training cohort and 41 in the validation cohort) were enrolled in the present study. High-resolution magnetic resonance images (HRMRI) were retrieved for tumor segmentation and feature extraction. HRMRI findings of RC were assessed by three experienced radiologists. Two radiomics nomograms were established by integrating the clinical risk factors, HRMRI findings and radiomics signature.

RESULTS

The predictive nomogram of LNMs showed good predictive performance (area under the curve [AUC], 0.90; 95% confidence interval [CI] 0.83-0.96) which was better than clinico-radiological (AUC, 0.83; 95% CI 0.74-0.93; Delong test, p = 0.017) or radiomics signature-only model (AUC, 0.77; 95% CI 0.67-0.86; Delong test, p = 0.003) in training cohort. Application of the nomogram in the validation cohort still exhibited good performance (AUC, 0.87; 95% CI 0.76-0.98). The accuracy, sensitivity and specificity of the combined model in predicting LNMs was 0.86,0.79 and 0.91 in training cohort and 0.83,0.85 and 0.82 in validation cohort. As for TDs, the predictive efficacy of the nomogram (AUC, 0.82; 95% CI 0.71-0.93) was not significantly higher than radiomics signature-only model (AUC, 0.80; 95% CI 0.69-0.92; Delong test, p = 0.71). Radiomics signature-only model was adopted to predict TDs with accuracy=0.76, sensitivity=0.72 and specificity=0.94 in training cohort and 0.68, 0.62 and 0.97 in validation cohort.

CONCLUSION

HRMRI-based radiomics models could be helpful for the prediction of LNMs and TDs preoperatively in RC patients.

The prognostic significance of tumor deposits in patients with head and neck squamous cell carcinomas

Background

A tumor deposit (TD) is a phenomenon that has not been well studied in head and neck squamous cell carcinoma (HNSCC) but might have prognostic significance. The present study was conducted to explore the presence and the prognostic significance of TDs in patients with HNSCCs.

Methods

Six hundred forty-two pathologically confirmed HNSCC patients with neck dissection samples were enrolled in this retrospective study. Patients were followed up and evaluated every 3 months in the first 3 years after surgery, and every 6 months thereafter by physical examination and computed tomography (CT)/magnetic resonance imaging (MRI) scans. The five-year overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) were compared in the TD and non-TD groups using multivariable analyses and propensity score matching (PSM) methodology (1:1).

Results

The 5-year OS, DSS, and RFS rate of all patients was 77.3%, 80.6%, and 71.9%, respectively. In the multivariable analyses, poorer rates of OS (HR =2.345, P<0.001), DSS (HR =2.818, P<0.001), and RFS (HR =2.536, P<0.001) were observed in the TD versus the non-TD group. In the PSM cohort, eighty-one patients who had TDs were paired with 70 patients without TDs. Significantly diminished rates of DSS (P=0.040) and RFS (P=0.004) were found in the TD versus the non-TD group.

Conclusions

In response to sparse reports regarding TDs in HNSCCs, the present study proposes the TD as an independent poor prognostic factor meriting further research because of its association with diminished OS, DSS, and RFS rates.

Utility of texture analysis on T2-weighted MR for differentiating tumor deposits from mesorectal nodes in rectal cancer patients, in a retrospective cohort

OBJECTIVE

The purpose of the study was to evaluate the utility of MR texture analysis for differentiating tumor deposits from mesorectal nodes in rectal cancer.

MATERIALS AND METHODS

Pretreatment MRI of 40 patients performed between 2006 and 2018 with pathologically proven tumor deposits and/or malignant nodes in the setting of rectal cancer were retrospectively reviewed. In total, 25 tumor deposits (TDs) and 71 positive lymph nodes (LNs) were analyzed for morphological and first-order texture analysis features on T2-weighted axial images. MR morphological features (lesion shape, size, signal heterogeneity, contrast enhancement) were analyzed and agreed in consensus by two experienced radiologists followed by assessment with Fisher's exact test. Texture analysis of the lesions was performed using TexRAD, a proprietary software algorithm. First-order texture analysis features (mean, standard deviation, skewness, entropy, kurtosis, MPP) were obtained after applying spatial scaling filters (SSF; 0, 2, 3, 4, 5, 6). Univariate analysis was performed with non-parametric Mann-Whitney U test. The results of univariate analysis were reassessed with generalized estimating equations followed by multivariate analysis. Using histopathology as a gold standard, diagnostic accuracy was assessed by obtaining area under the receiver operating curve.

RESULTS

MR morphological parameter, lesion shape was a strong discriminator between TDs and LNs with a p value of 0.02 (AUC: 0.76, 95% CI of 0.66 to 0.84, SE: 0.06) and sensitivity, specificity of 90% and 68%, respectively. Skewness extracted at fine filter (SSF-2) was the only significant texture analysis parameter for distinguishing TDs from LNs with p value of 0.03 (AUC: 0.70, 95% CI of 0.59 to 0.79, SE: 0.06) and sensitivity, specificity of 70% and 72%, respectively. When lesion shape and skewness-2 were combined into a single model, the diagnostic accuracy was improved with AUC of 0.82 (SE: 0.05, 95% CI of 0.72 to 0.88 with p value of < 0.01). This model also showed a high sensitivity of 91% with specificity of 68%.

CONCLUSION

Lesion shape on MR can be a useful predictor for distinguishing TDs from positive LNs in rectal cancer patients. When interpreted along with MR texture parameter of skewness, accuracy is further improved.

A Modified Pathological N Stage Including Status of Tumor Deposits in Colorectal Cancer With Nodal Metastasis

Background

The American Joint Committee on Cancer 8th classification states that colorectal cancer (CRC) is classified as N1c stage when regional lymph nodes (LNs) are negative and tumor deposits (TDs) are positive. However, how to classify TDs when regional LNs are positive remains unclear. The current study aimed to investigate the possibility of combining positive LNs and positive TDs to develop a modified pathological N (mpN) stage for CRC.

Methods

We retrospectively analyzed 9,198 patients with stage III CRC from the Surveillance, Epidemiology, and End Results program who underwent surgery (6,440 in the training cohort and 2,758 the validation cohort). The combination of positive LNs and TD status was defined as mpN stage. Overall survival (OS) according to mpN and pathological N (pN) stages was analyzed by the Kaplan–Meier method. The area under the curves (AUCs) and Akaike’s information criterion (AIC) were applied to assess the predictive discrimination abilities and goodness-of-fit of the model. The clinical benefits were measured using decision curve analyses. The validation cohort was used to validate the results.

Results

AUC analysis showed that the prognostic discrimination of mpN stage (AUC = 0.628, 95% confidence interval (CI), 0.616–0.640) was better than that of pN stage (AUC = 0.618, 95% CI, 0.606–0.630, p = 0.006) for OS. The AIC demonstrated that mpN stage (AIC = 30,217) also showed superior model-fitting compared with pN stage (AIC = 30,257) and decision curve analyses revealed that mpN stage had better clinical benefits than pN stage. Similar results were found in the validation cohort.

Conclusions

Among patients with CRC and LN metastasis, mpN stage might be superior to pN stage for assessing prognosis and survival, suggesting that TD status should be included in the pN stage.

The Role of Tumor Deposits in Predicting the Efficacy of Chemotherapy in Stage III Colon Cancer

Purpose

To evaluate the role of tumor deposits (TDs) in predicting the efficacy of chemotherapy in stage III colon cancer.

Methods

Using the SEER^∗Stat software Version 8.3.6, we started with a national cohort of colon cancer cases diagnosed between 2004 and 2016. We used the χ² (Chi-square) test to compare differences between different categorical variables according to the number of TDs. The Cox proportional hazards regression model was used to determine the independent association of different clinical and pathological variables with CSS, which were adjusted for other significant prognostic factors.

Results

We have identified 29,017 patients diagnosed with stage III colon cancer from the SEER database. The results of multivariate analyses showed that patients with the receipt of chemotherapy had 54.7% decreased risk of cancer-specific mortality compared with those not (HR = 0.453, 95% CI = 0.425-0.483, P < 0.0001) in the no-TD group; In the 1-2-TD group, patients with the receipt of chemotherapy had 56.8% decreased risk of cancer-specific mortality compared with those not (HR = 0.432, 95% CI = 0.364-0.512, P < 0.0001); In the ≥3-TD group, patients with the receipt of chemotherapy had 51.8% decreased risk of cancer-specific mortality compared with those not (HR = 0.482, 95% CI = 0.389-0.597, P < 0.0001).

Conclusions

Our study demonstrated that the presence of TDs was associated with a dismal prognosis and high number of TDs would also contribute to the worse survival of colon cancer. High number of TDs did not affect the survival benefit of chemotherapy in stage III colon cancer.

Prognostic Values of Preoperative Inflammatory and Nutritional Markers for Colorectal Cancer

Background

Increasing evidence indicates that inflammation and nutritional status are associated with survival outcomes in patients with colorectal cancer (CRC). This study aimed to investigate the prognostic values of preoperative inflammatory and nutritional factors and develop a prognostic model individually predicting overall survival (OS) and disease-free survival (DFS) in patients with CRC.

Methods

We retrospectively collected data on patients with CRC who underwent radical surgery. Independent prognostic inflammatory and nutritional markers were identified and novel prognostic models were developed incorporating the identified factors. The discriminative ability and model-fitting performance were evaluated by receiver operating characteristic curves and Akaike information criteria. Clinical usefulness was assessed by decision curve analysis.

Results

A total of 400 eligible patients were identified. Multivariate analysis identified pN stage, tumor differentiation grade, neutrophil count, and body mass index as independent prognostic factors for OS, and pN stage, tumor differentiation grade, neutrophil count, neutrophil-lymphocyte ratio, and serum albumin as prognostic factors for DFS. The combined inflammatory and nutritional prognostic model showed better discriminative ability, model-fitting performance, and net benefits than the inflammatory and nutritional models alone, and the American Joint Committee on Cancer (AJCC) 8th TNM classification for predicting OS and DFS.

Conclusion

Preoperative nutritional and inflammatory factors have significant prognostic value in patients with CRC. A novel prognostic model incorporating preoperative inflammatory and nutritional markers provides better prognostic performance than the AJCC 8th TNM classification. A novel nomogram incorporating preoperative inflammatory and nutritional markers can individually predict OS and DFS in patients with CRC.

Clinical Significance of Tumor Deposits in Gastric Cancer: a Retrospective and Propensity Score-Matched Study at Two Institutions

BACKGROUND

Gastric cancer (GC) treatment is largely determined by tumor stage. Despite improvements in the mode of treatment of various types of advanced disease, staging is still evolving. The role of tumor deposits (TDs) in staging remains debated. The purpose of this research is to investigate the relationship between TDs and prognosis in GC.

METHODS

A total of 3098 patients were considered eligible for prognostic analysis (2706 patients in the TDs-negative group and 392 patients in the TDs-positive group). A one-to-one propensity score-matching analysis was performed using a logistic regression mode and the following covariates: age, gender, tumor location, size, differentiation, perineural invasion, lymphovascular invasion, pTNM stage, type of gastrectomy, and the number of lymph nodes retrieved between TDs-negative and TDs-positive group, then 323 patients in each group were analyzed. Univariate and multivariate analyses of prognostic factors were conducted accordingly. The predictive ability of different staging system incorporating TDs was evaluated.

RESULTS

TDs were present in 14.5% cases and almost all of the patients (99%) suffered from advanced GC. Multivariate analysis showed that pN stage, chemotherapy, and TDs were the independent prognostic factors. The TDs-positive group showed a lower rate of 5-year disease-free survival compared with the TDs-negative group in all patients, stage II, and stage III patients (p = 0.001, 0.029, and 0.003, respectively). The 5-year disease-free survival for patients with TDs and without TDs was 27.6% and 34.4%, respectively.

CONCLUSIONS

Our research shows that TDs are closely associated with prognosis in GC. TDs should be incorporated into the TNM staging system, which could then accurately improve the staging reliability and prognostic assessment.

Rectal cancer: a methodological approach to matching PET/MRI to histopathology

Purpose

To enable the evaluation of locoregional disease in the on-going RECTOPET (REctal Cancer Trial on PET/MRI/CT) study; a methodology to match mesorectal imaging findings to histopathology is presented, along with initial observations.

Methods

FDG-PET/MRI examinations were performed in twenty-four consecutively included patients with rectal adenocarcinoma. In nine patients, of whom five received neoadjuvant treatment, a postoperative MRI of the surgical specimen was performed. The pathological cut-out was performed according to clinical routine with the addition of photo documentation of each slice of the surgical specimen, meticulously marking the location, size, and type of pathology of each mesorectal finding. This allowed matching individual nodal structures from preoperative MRI, via the specimen MRI, to histopathology.

Results

Preoperative MRI identified 197 mesorectal nodal structures, of which 92 (47%) could be anatomically matched to histopathology. Of the matched nodal structures identified in both MRI and histopathology, 25% were found to be malignant. These malignant structures consisted of lymph nodes (43%), tumour deposits (48%), and extramural venous invasion (9%). One hundred eleven nodal structures (55%) could not be matched anatomically. Of these, 97 (87%) were benign lymph nodes, and 14 (13%) were malignant nodal structures. Five were malignant lymph nodes, and nine were tumour deposits, all of which had a short axis diameter < 5 mm.

Conclusions

We designed a method able to anatomically match and study the characteristics of individual mesorectal nodal structures, enabling further research on the impact of each imaging modality. Initial observations suggest that small malignant nodal structures assessed as lymph nodes in MRI often comprise other forms of mesorectal tumour spread.

Trial registration

Clinical Trials Identifier:NCT03846882.

Can extranodal tumour deposits be diagnosed on MRI? Protocol for a multicentre clinical trial (the COMET trial)

INTRODUCTION

Tumour deposits (TDs) are a poor prognostic marker when seen on pathology, and are worse than lymph node metastases (LNMs). They are now being reported on MRI as discontinuous nodules of extramural venous invasion but this diagnosis has not been validated and it is unclear how it correlates with the diagnosis of TDs on pathology.

METHODS AND ANALYSIS

This is a prospective interventional clinical trial which aims to directly map the location of TDs on MRI and correlate what is seen on MRI with the pathology findings at each location. All patients with rectal cancer undergoing resectional surgery are eligible (including those undergoing preoperative therapy). The primary outcome is the prevalence of TDs seen on pathology. Secondary outcomes are to assess radiological and pathological interobserver agreement, assess the effect of TDs on prognosis and carry out exploratory work looking at differences between TDs and LNMs. The estimated sample size is 100 to detect a twofold increase in the pathological diagnosis of TD when MRI mapping is used.

ETHICS AND DISSEMINATION

Ethical approval has been granted from the South Central-Hampshire B Research and Ethics Committee (IRAS 217627). The study will be carried out under standard operative procedures within the Royal Marsden Hospital.

TRIAL REGISTRATION NUMBER

NCT03303547.

Pitfalls and value of organ specific approach in evaluating indeterminate lesions detected on CT in colorectal cancer by [F18] FDG PET/CT

Objective

The objective of this study is to evaluate the value of FDG PET/CT for different involved organs showing Indeterminate/ equivocal / suspicious lesions detected on IV contrasted CT during surveillance follow up for colorectal cancer.

Materials and methods

A total of 67 patients with colorectal cancer how are on regular surveillance follow up by IV contrasted CT scans revealing indeterminate lesions were studied. Subsequent FDG PET/CT evaluation was performed as a problem solving modality. PET/CT results were statistically characterized when compared to biopsy results or to follow/up results. Also Statistical parameters were calculated for each organ involved. The evaluation of all CT indeterminate lesions by FDG PET/CT showed overall sensitivity of 93%, Specificity of 81%, Negative predictive value of 94%, Positive predictive value 80% and accuracy of 87%. However in an organ specific approach the highest accuracy was for lymph nodes with results showing a 100% accuracy and the lowest accuracy was for local disease at a value of 80%. Probable explanations for the falsely characterized lesions resulting in the pitfalls seen and in the imperfect accuracy were provided.

Conclusion

Study shows that FDG PET/CT is an excellent tool in characterizing CT indeterminate lesions during surveillance of colorectal cancer, However different organs showed variable accuracy results with the highest accuracy for our study was for lymph node status (100%) and the lowest accuracy being for local disease at the original site of primary tumor (80%).

Prognostic value of tumor deposits in rectal cancer: A monocentric series of 505 patients

BACKGROUND AND OBJECTIVES

It has been suggested that tumor deposits (TDs) may have a worse prognosis in rectal cancer compared with colonic cancer. The aim of this study was to assess TDs prognosis in rectal cancer.

METHODS

Patients who underwent total mesorectum excision for rectal adenocarcinoma (2011-2016) were included. A case-matched analysis was performed to assess the accurate impact of TDs for each pN category after exclusion of synchronous metastasis.

RESULTS

A total of 505 patients were included. TDs were observed in 99 (19.6%) patients, (pN1c = 37 [7.3%]). TDs were associated with pT3-T4 stage (P = .037), synchronous metastasis (P = .003), lymph node (LN) invasion (P = .041), vascular invasion (P = .001), and perineural invasion (P < .001). TD was associated with a worse 3-year disease-free survival (DFS) among pN0 (51.2% vs 79.8%; P < .001); pN1 patients (35.2% vs 70.1%; P = .004) but not among pN2 patients (37.5% vs 44.7%; P = .499). After matching, pN1c patients had a worse 3-year DFS compared with pN0 patients (58.6% vs 82.4%; P = .035) and a tendency toward a worse DFS among N1 patients (40.1% vs 64.2%; P = .153). DFS was worse when one TD was compared with one invaded LN (40.8% vs 81.3%; P < .001).

CONCLUSION

In rectal cancer, TDs have a metastatic risk comparable to a pN2 stage which may lead to changes in adjuvant treatment.

Impact on colorectal cancer pathology reporting practice of migration from TNM 5 to TNM 8

AIMS

The introduction of TNM 8 into UK pathology practice in January 2018 considers tumour deposits in colorectal cancer staging for the first time. The impact of this new classification on pathology reporting practices has yet to be evaluated.

METHODS AND RESULTS

A clinical audit was conducted, comparing consecutive colorectal cancer resection specimens reported under TNM 5 classification guidelines in 2017 (n = 177) and TNM 8 guidelines in 2018 (n = 234). Tumour features (venous invasion, perineural invasion, lymph node metastatic disease, tumour deposits) and changes in reporting practices were evaluated among four specialist gastrointestinal pathologists working within a large pathology department. Adoption of TNM 8 practice led to an approximate doubling in the use of ancillary stains (41.0% of TNM 8 versus 22.0% of TNM 5 cases, P < 0.001) to help evaluate tumours. A narrowing of the range between pathologists was observed in reporting cases as having one or more form of regional, extramural, discontinuous tumour (TNM 5 range = 50.0-79.0%, TNM 8 range = 57.8-65.7%), with no change in the overall proportion of cases reported as such (62.7% versus 62.4%, P = 0.95). However, significant interobserver variation in reporting rates for individual parameters remained.

CONCLUSION

TNM 8 colorectal cancer staging offers potentially greater reproducibility in pathology reporting of regional, extramural, discontinuous disease with similar proportions of patients reported as having one or more of these forms of tumour spread compared with TNM 5. Further guidance in defining individual features is required to reduce interobserver variation in pathology assessments and to help elucidate the clinical significance of each parameter.

Prognostic Significance of Tumor Deposits in Combination with Lymph Node Metastasis in Stage III Colon Cancer: A Propensity Score Matching Study

Tumor deposits in colon cancer are related to poor prognosis, whereas the prognostic power of tumor deposits in combination with lymph node metastasis (LNM) is controversial. This study aimed to compare the overall survival between LNM alone and LNM in combination with tumor deposits, and to verify whether the number of tumor deposits can be considered LNM in patients with both LNM and tumor deposits in stage III colon cancer by propensity score matching (PSM). Patients carrying resected stage III adenocarcinoma of colon cancer were identified from the Surveillance, Epidemiology, and End Results database (2010–2015). The Kaplan-Meier method, Cox proportional hazard models and PSM were used. On the whole, 23,168 patients (20,451 (88.3%) with only LNM and 2,717 (11.7%) with both LNM and tumor deposits) were selected. After undergoing PSM, patients with both LNM and tumor deposits showed worse overall survival (hazard ratio = 1.33, 95% confidence interval: 1.20–1.47, P < 0.001). After the number of tumor deposits was added with that of positive regional lymph nodes, patients with both LNM and tumor deposits seemed to have prognostic implications similar to those with LNM alone (hazard ratio = 1.02, 95% confidence interval: 0.93–1.12, P = 0.66). The simultaneous presence of LNM and tumor deposits, as compared with the presence of only LNM, had an association with a worse outcome. Tumor deposits should be considered as LNM in patients with both tumor deposits and LNM in stage III colon cancer.

Verification of the Japanese staging system for rectal cancer, focusing on differences with the TNM classification

PURPOSE

The 9th Japanese Classification of Colorectal Cancer (9th JSCCR) has two main differences from the TNM classification (8th AJCC): first, main or lateral lymph node metastasis is classified as jN3; second, tumor nodules (ND) are treated as lymph node metastasis. In this study, we verified the 9th JSCCR for rectal cancer, focusing on the differences with the 8th AJCC.

METHODS

This retrospective analysis involved 212 patients with stage I-III rectal cancer. ND was evaluated using whole-mount sections. We evaluated the relapse-free survival of each staging system, and compared the prognostic significance of the different staging systems using the Akaike information criterion (AIC) and Harrell's concordance index (c-index).

RESULTS

Main or lateral lymph node metastasis was detected in nine of 212 (4%) patients. ND was detected in 79 of 212 (37%) patients. The best risk stratification power was observed in the 9th JSCCR (AIC, 759; c-index, 0.708) compared with the 7th JSCCR (AIC, 771; c-index, 0.681), 8th JSCCR (AIC, 768; c-index, 0.696), and the 8th AJCC (AIC, 766; c-index, 0.691).

CONCLUSIONS

The 9th JSCCR, which includes the concepts of jN3 and ND, is useful for the risk stratification of rectal cancer, and the contributes to precise decision-making for follow-up management and adjuvant therapy.

Can Ex Vivo Magnetic Resonance Imaging of Rectal Cancer Specimens Improve the Mesorectal Lymph Node Yield for Pathological Examination?

Supplemental digital content is available in the text.

The aim of this study was to use 7 T ex vivo magnetic resonance imaging (MRI) scans to determine the size of lymph nodes (LNs) in total mesorectal excision (TME) specimens and to increase the pathological yield of LNs with MR-guided pathology.

Prognostic Value of Tumor Deposits for Disease-Free Survival in Patients With Stage III Colon Cancer: A Post Hoc Analysis of the IDEA France Phase III Trial (PRODIGE-GERCOR)

PATIENTS AND METHODS

A post hoc analysis of all pathologic reports from patients with stage III CC included in the IDEA France phase III study (ClinicalTrials.gov identifier: NCT00958737) investigating the duration of adjuvant fluorouracil, leucovorin, and oxaliplatin or capecitabine and oxaliplatin therapy (3 v 6 months) was performed. The primary objective was to determine the prognostic impact of TD on disease-free survival (DFS). The effect of the addition of TD to LNM count on pN restaging was also evaluated. A multivariable analysis was performed to establish the association between TD and DFS.

RESULTS

Of 1,942 patients, 184 (9.5%) had TDs. The pN1a/b and pN1c populations showed similar DFS. TD-positive patients had worse prognosis compared with TD-negative patients, with 3-year DFS rates of 65.6% (95% CI, 58.0% to 72.1%) and 74.7% (95% CI, 72.6% to 76.7%; P = .0079), respectively. On multivariable analysis, TDs were associated with a higher risk of recurrence or death (hazard ratio [HR], 1.36; P = .0201). Other adverse factors included pT4 and/or pN2 disease (HR, 2.21; P < .001), the 3 months of adjuvant treatment (HR, 1.29; P = .0029), tumor obstruction (HR, 1.28; P = .0233), and male sex (HR, 1.24; P = .0151). Patients restaged as having pN2 disease (n = 35, 2.3%) had similar DFS as patients initially classified as pN2.

CONCLUSION

The presence of TDs is an independent prognostic factor for DFS in patients with stage III CC. The addition of TD to LNM may help to better define the duration of adjuvant therapy.

Tumor deposit serves as a prognostic marker in gastric cancer: A propensity score-matched analysis comparing survival outcomes

BACKGROUND

Gastric cancer (GC) treatment is determined by accurate tumor staging. The value of tumor deposit (TD) in prognostic prediction staging system is not yet determined.

METHODS

We retrospectively analyzed clinical information on GC patients who underwent gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital from July 2014 to June 2016. Propensity score matching (PSM) was performed to reduce the possibility of selection bias according to the presence of TD.

RESULTS

Of the 1034 GC patients, 240 (23.21%) presented with TD, which was associated with younger age and larger tumor size (all P < .05). TD-positive patients had a worse survival than TD-negative patients before (P < .001) and after (P = .017) matching. Multivariable analysis showed that mortality risk of patients with TD increased by 58%, 62%, 37%, and 40% in the crude (HR = 1.58, 95% CI 1.32-1.89, P < .001), adjusted I (HR = 1.62, 95% CI 1.35-1.94, P < .001), adjusted II (HR = 1.37, 95% CI 1.13-1.66, P = .001), and adjusted III (HR = 1.40, 95% CI 1.16-1.68, P < .001) models before matching. Similarly, in the PSM cohort patients with TD had worse prognosis in the crude (HR = 1.32, 95% CI 1.07-1.63, P = .011), adjusted I (HR = 1.35, 95% CI 1.09-1.67, P = .005), adjusted II (HR = 1.26, 95% CI 1.00-1.58, P = .049), and adjusted III (HR = 1.33, 95% CI 1.07-1.65, P = .010) models. TD had a similar value range between N1 and N2 stages among different models.

CONCLUSIONS

Among GC patients, TD is associated with survival and may have a role in the staging of patients.

SIRT2-dependent IDH1 deacetylation inhibits colorectal cancer and liver metastases

Protein lysine acetylation affects colorectal cancer (CRC) distant metastasis through multiple pathways. In a previous proteomics screen, we found that isocitrate dehydrogenase 1 (IDH1) is hyperacetylated in CRC primary tumors and liver metastases. Here, we further investigate the function of IDH1 hyperacetylation at lysine 224 in CRC progression. We find that IDH1 K224 deacetylation promotes its enzymatic activity and the production of α-KG, and we identify sirtuin-2 (SIRT2) as a major deacetylase for IDH1. SIRT2 overexpression significantly inhibits CRC cell proliferation, migration, and invasion. IDH1 acetylation is modulated in response to intracellular metabolite concentration and regulates cellular redox hemostasis. Moreover, IDH1 acetylation reversely regulates HIF1α-dependent SRC transcription which in turn controls CRC progression. Physiologically, our data indicate that IDH1 deacetylation represses CRC cell invasion and migration in vitro and in vivo, while the hyperacetylation of IDH1 on K224 is significantly correlated to distant metastasis and poor survival of colorectal cancer patients. In summary, our study uncovers a novel mechanism through which SIRT2-dependent IDH1 deacetylation regulates cellular metabolism and inhibits liver metastasis of colorectal cancer.

Pathways of spread in rectal cancer: a reappraisal of the true routes to distant metastatic disease

Rectal cancer can spread in a number of ways which have been previously recognised and validated as prognostic markers. These routes of spread are not adequately recognised in the stage grouping of the tumour-node-metastasis system, which focuses predominantly on the depth of invasion and nodal status, thus limiting its prognostic accuracy. Tumour spread involving veins occurs in 40% of patients. Venous channels have greater direct access to distant sites by means of a vascular 'anatomical highway'. This rapid spread of tumour cells to distant metastatic sites by veins cannot occur by means of lymph node pathways. Thus, lymph nodes have been overestimated in their importance. Distinction between local tumour spread (lymph node metastases, perineural and lymphatic invasion) and tumour spread mediated by a direct vascular pathway to distant dissemination (extramural venous invasion and tumour deposits) must be made as the implications for prognosis and choice of treatment are not likely to be equal. Improved precision of radiological and pathological assessment is needed to scrutinise and carefully document each route of tumour spread. Only with this accurate information will it be possible to correctly weight each feature and develop a more prognostically accurate staging method that would allow separation of true high- and low-risk groups and subsequent improvements in patient care.

How to measure tumour response in rectal cancer? An explanation of discrepancies and suggestions for improvement

Various methods categorize tumour response after neoadjuvant therapy, including down-staging and tumour regression grading. Response categories allow comparison of different treatments within clinical trials and predict outcome. A reproducible response categorization could identify subgroups with high or low risk for the most appropriate subsequent treatments, like watch and wait. Lack of standardization and interpretation difficulties currently limit the usability of these approaches. In this review we describe these difficulties for the evaluation of chemoradiation in rectal cancer. An alternative approach of tumour response is based on patterns of residual disease, including fragmentation. We summarise the evidence behind this alternative method of response categorisation, which explains a number of very relevant clinical discrepancies. These issues include differences between downstaging and tumour regression, high local regrowth in advanced tumours during watchful waiting procedures, the importance of resection margins, the limited value of post-treatment biopsies and the relatively poor outcome of patients with a near complete pathological response. Recognition of these patterns of response can allow meaningful development of novel biomarkers in the future.

Reconsidering the prognostic significance of tumour deposit count in the TNM staging system for colorectal cancer

Although the occurrence of tumour deposits (TDs) without metastatic lymph nodes (mLNs) is classified as “N1c” in the 8^th TNM staging system for colorectal cancer (CRC), the prognostic significance of the TD count is still controversial. A total of 39155 CRC patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database. The potential associations between baseline characteristics and TD status were evaluated using the χ² test. Cancer-specific survival (CSS) rates were calculated by using the Kaplan-Meier method, and CSS comparisons were performed by using the log-rank test. The results showed that TD count was an important prognostic factor and that the number of TDs was negatively correlated with the prognosis of CRC patients. We found that the prognostic value of one TD is equivalent to that of two mLNs based on the comparison of CSS rates. Accordingly, we proposed a novel N staging system by integrating the TD count into the N category with the ratio of TDs to mLNs being 1:2. There were no prognostic differences in patients with or without TDs in each novel N category. Weighing one TD as two mLNs in this novel TNM staging system is superior to the “N1c” classification in the 8^th TNM staging system in evaluating the prognosis of CRC patients.

Beyond the NCCN Risk Factors in Colon Cancer: An Evaluation in a Swedish Population-Based Cohort

Background

The purpose of this study was to investigate whether pT3–4 and pN-subclassifications, lymph-node ratio (LNR), tumour deposits, pre- and postoperative carcinoembryonic antigen (CEA), and C-reactive protein (CRP)—all parameters commonly collected in clinical management—add information about recurrence risk against a background of routine clinicopathological parameters as defined by the NCCN.

Methods

The prospective cohort consisted of all 416 patients diagnosed with colon cancer stage I–III in Uppsala County between 2010 and 2015. Cox proportional hazard models were used to calculate hazard ratios for time to recurrence and overall survival. The results were compared with the entire Swedish population concerning parameters recorded in the national quality registry, SCRCR, during the same time period.

Results

The Uppsala cohort was representative of the entire Swedish cohort. In unadjusted analyses, pT3-subclassification, pN-subclassification, LNR, tumour deposits, elevated postoperative CEA, and preoperative CRP correlated with recurrence. After adjusting for T-, N-stage, and NCCN risk factors, pN-subclassification, sidedness, and elevated postoperative CEA levels correlated with recurrence. Survival correlated with parameters associated with recurrence, LNR, and elevated postoperative CRP.

Conclusions

Additional information on recurrence risk is available from several routinely recorded parameters, but most of the risk is predicted by the commonly used clinicopathological parameters.

Electronic supplementary material

The online version of this article (10.1245/s10434-019-08148-3) contains supplementary material, which is available to authorized users.

Preoperative prediction of tumour deposits in rectal cancer by an artificial neural network-based US radiomics model

OBJECTIVE

To develop a machine learning-based ultrasound (US) radiomics model for predicting tumour deposits (TDs) preoperatively.

METHODS

From December 2015 to December 2017, 127 patients with rectal cancer were prospectively enrolled and divided into training and validation sets. Endorectal ultrasound (ERUS) and shear-wave elastography (SWE) examinations were conducted for each patient. A total of 4176 US radiomics features were extracted for each patient. After the reduction and selection of US radiomics features , a predictive model using an artificial neural network (ANN) was constructed in the training set. Furthermore, two models (one incorporating clinical information and one based on MRI radiomics) were developed. These models were validated by assessing their diagnostic performance and comparing the areas under the curve (AUCs) in the validation set.

RESULTS

The training and validation sets included 29 (33.3%) and 11 (27.5%) patients with TDs, respectively. A US radiomics ANN model was constructed. The model for predicting TDs showed an accuracy of 75.0% in the validation cohort. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and AUC were 72.7%, 75.9%, 53.3%, 88.0% and 0.743, respectively. For the model incorporating clinical information, the AUC improved to 0.795. Although the AUC of the US radiomics model was improved compared with that of the MRI radiomics model (0.916 vs. 0.872) in the 90 patients with both ultrasound and MRI data (which included both the training and validation sets), the difference was nonsignificant (p = 0.384).

CONCLUSIONS

US radiomics may be a potential model to accurately predict TDs before therapy.

KEY POINTS

• We prospectively developed an artificial neural network model for predicting tumour deposits based on US radiomics that had an accuracy of 75.0%. • The area under the curve of the US radiomics model was improved than that of the MRI radiomics model (0.916 vs. 0.872), but the difference was not significant (p = 0.384). • The US radiomics-based model may potentially predict TDs accurately before therapy, but this model needs further validation with larger samples.

Cdh1-mediated Skp2 degradation by dioscin reprogrammes aerobic glycolysis and inhibits colorectal cancer cells growth

BACKGROUND

The F-box protein S-phase kinase-associated protein 2 (Skp2) is overexpressed and correlated with poor prognosis in human malignancies, including colorectal cancer (CRC).

METHODS

A natural product library was used for natural compound screening through glycolysis analysis. The expression of Skp2 in CRCs and the inhibitory effect of dioscin on glycolysis were examined through methods of immunoblot, immunofluorescence, immunohistochemical staining, anchorage-dependent and -independent growth assays, EdU incorporation assay, ubiquitination analysis, co-immunoprecipitation assay, CRISPR-Cas9-based gene knockout, and xenograft experiment.

FINDINGS

We demonstrated that Skp2 was highly expressed in CRC tissues and cell lines. Knockout of Skp2 inhibited HK2 and glycolysis and decreased CRC cell growth in vitro and in vivo. We screened 88 commercially available natural products and found that dioscin, a natural steroid saponin derived from several plants, significantly inhibited glycolysis in CRC cells. Dioscin decreased the protein level of Skp2 by shortening the half-life of Skp2. Further study showed that dioscin attenuated Skp2 phosphorylation on S72 and promoted the interaction between Skp2 and Cdh1, which eventually enhanced Skp2 lysine 48 (K48)-linked polyubiquitination and degradation. Depletion of Cdh1 impaired dioscin-induced Skp2 reduction, rescued HK2 expression, and glycolysis in CRC cells. Finally, dioscin delayed the in vivo tumor growth, promoted Skp2 ubiquitination, and inhibited Skp2 expression in a mouse xenograft model.

INTERPRETATION

This study suggests that in addition to pharmacological inactivation of Skp2, enhancement of ubiquitination-dependent Skp2 turnover is a promising approach for cancer treatment.

Assessment of a Staging System for Sigmoid Colon Cancer Based on Tumor Deposits and Extramural Venous Invasion on Computed Tomography

IMPORTANCE

Preoperative TNM stratification of colon cancer on computed tomography (CT) does not identify patients who are at high risk of recurrence that could be selected for preoperative treatment.

OBJECTIVE

To evaluate the utility of CT findings for prognosis of sigmoid colon cancer.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study used retrospective data from patients who underwent bowel resection for sigmoid colon cancer between January 1, 2006, and January 1, 2015, at a tertiary care center receiving international and national referrals for colorectal cancer. Statistical analysis was performed in April 2019.

MAIN OUTCOMES AND MEASURES

Cox proportional hazards regression analysis was performed to investigate CT findings associated with disease recurrence. Kaplan-Meier survival plots were calculated for disease-free survival using CT staging systems.

RESULTS

Of the 414 patients who had sigmoid colon cancer (248 [60.0%] men; mean [SD] age, 66.1 [12.7] years), with median follow-up of 61 months (interquartile range, 40-87 months), 122 patients (29.5%) developed disease recurrence. On multivariate analysis, nodal disease was not associated with disease recurrence; only tumor deposits (hazard ratio [HR], 1.90; 95% CI, 1.21-2.98; P = .006) and extramural venous invasion (HR, 1.97; 95% CI, 1.26-3.06; P = .003) on CT were associated with disease recurrence. Significant differences in disease-free survival were found using CT-T3 substage classification (HR, 1.88; 95% CI, 1.32-2.68) but not CT-TNM (HR, 1.55; 95% CI, 0.94-2.55). The presence of tumor deposits or extramural venous invasion on CT (HR, 2.45; 95% CI, 1.68-3.56) had the strongest association with poor outcome.

CONCLUSIONS AND RELEVANCE

In this study, T3 substaging and detection of tumor deposits or extramural venous invasion on preoperative CT scans of sigmoid colon cancer were prognostic factors for disease-free survival, whereas TNM and nodal staging on CT had no prognostic value. T3 substaging and detection of tumor deposits or extramural venous invasion of sigmoid colon cancer was superior to TNM on CT and could be used to preoperatively identify patients at high risk of recurrence.

The unique prognostic characteristics of tumor deposits in colorectal cancer patients

Background

Both AJCC 7th and 8th TNM systems have included tumor deposits (TDs) in nodal staging when lymph nodes metastases (LNMs) are negative in colorectal cancer (CRC). However, the prognostic role of TDs has not been determined in the presence of positive LNMs.

Methods

Two independent large-scale cohorts of CRC patients from the Surveillance Epidemiology and End Results (SEER) database (n=69,178) [2010-2013] and Fudan University Shanghai Cancer Center (FUSCC) (n=3,137) [2010-2014] were retrospectively analyzed. Kaplan-Meier method was used to estimate survival curves and univariate and multivariate analyses were performed by Cox proportional hazard model.

Results

TDs were observed in 12.3% (n=8,480) and 14.8% (n=463) of patients in the SEER and FUSCC cohorts, respectively. Multivariate analysis suggested TDs were an independent adverse prognostic factors for overall survival (OS) (P<0.001). Remarkably, both cohorts showed the presence of TDs was significantly associated with OS, but not was the number of TDs (P=0.982 and P=0.252 for the SEER and FUSCC cohorts, respectively). In the presence of LNMs, positive TDs were associated with a shorter OS [hazard ratio (HR): 2.69, 95.0% confidence interval (CI): 2.597-2.778; P<0.001]. Further analysis combining TDs with LNMs demonstrated that the prognosis of patients with N1TD (N1 with positive TDs) was same as the N2 patients, and N2TD (N2 with positive TDs) patients had much worse prognosis than N2 (P<0.001).

Conclusions

Our results have shown the unique features of TDs in patients with CRC, different from LNMs. In the presence of LNMs, TDs should also be considered in TMN system.

Tumor deposit indicates worse prognosis than metastatic lymph node in gastric cancer: a propensity score matching study

Background

The prognostic value of tumor deposit (TD) in gastric cancer is controversial. This study aims to investigate the prognostic value of TD.

Methods

The consecutive patients diagnosed with gastric cancer from October 2007 to October 2012 were selected. The patients were divided by whether they suffered TD into two groups. The basic data were comparable between the two groups after propensity score matching (PSM), then survival analysis [overall survival (OS) and cancer-specific survival (CSS)] was applied in two groups. After that, all the patients were divided by pN staging and survival analysis were applied in each subgroup. At last, all patients were divided into TD group, pN1 stage group, pN2 stage group, pN3a, and pN3b stage group, OS and CSS were compared between them. Multivariable competing risk analyses tested association of TD with OS and CSS, before and after PSM.

Results

Eight hundred and three patients were concluded. After PSM, 137 patients with TD and 274 patients without TD were selected, the 5-year OS and CSS rates of patients with TD were significantly worse than patients without TD (OS: 19.7% vs. 42.0%, P<0.001; CSS: 22.6% vs. 45.6%, P<0.001). In all patients' survival analysis, the 5-year OS and CSS rates of TD group were comparable with pN3a group (OS: 19.7% vs. 25.3%, P=0.221, CSS: 22.6% vs. 30.1%, P=0.092) and pN3b group (OS: 19.7% vs. 19.6% P=0.349, CSS: 22.6% vs. 23.5%, P=0.452). Meanwhile, on multivariable cox regression analyses, the presence of TD significantly reduces the OS and CSS of patients in gastric cancer.

Conclusions

TD has a marked impact on the prognosis of gastric cancer. Even patients with TD had the same prognosis with pN3 stage.

Prognostic Significance of Tumor Deposits in Patients With Stage III Colon Cancer: A Nomogram Study

BACKGROUND

The clinical characteristics of stage III colon cancer and the prognostic significance of tumor deposits were investigated, to construct a prognostic nomogram.

METHODS

The data of patients were retrieved from the Surveillance, Epidemiology, and End Results database. Patients were randomized to a training or validation cohort. The Kaplan-Meier method was used to analyze survival rates. In the training cohort, a prognostic nomogram was established via Cox regression and then tested in the validation cohort. The accuracy and discrimination of the nomogram were assessed using concordance indices (C-indices) and calibration curves.

RESULTS

Of the 9246 patients meeting the inclusion criteria, 1788 (19.3%) had tumor deposits. Patients with tumor deposits only showed similar survival rates to those with lymph node metastases only (P = 0.83). Compared with these, patients with both tumor deposits and lymph node metastases exhibited significantly worse survival (P < 0.01). In the multivariate Cox regression analyses, the following were identified as independent prognostic indicators and adopted to formulate the nomogram: tumor deposits, age, ethnicity, T stage, the number of positive regional lymph nodes, grade, and carcinoembryonic antigen. In the training cohort, the calibration curve showed good consistency, and the concordance index of the nomogram for predicting overall survival reaches 0.727 (95% CI: 0.71524-0.73876), superior to the concordance index of the American Joint Committee on Cancer staging system (0.594, 95% CI: 0.58224-0.60576). These results are supported in the validation cohort.

CONCLUSIONS

Tumor deposits may be an independent prognostic factor for patients with stage III colon cancer after colectomy. The nomogram constructed herein accurately predicted overall survival.

Current concepts in imaging for local staging of advanced rectal cancer

Imaging of rectal cancer has an increasingly pivotal role in the diagnosis, staging, and treatment stratification of patients with the disease. This is particularly true for advanced rectal cancers where magnetic resonance imaging (MRI) findings provide essential information that can change treatment. In this review we describe the rationale for the current imaging standards in advanced rectal cancer for both morphological and functional imaging on the baseline staging and reassessment studies. In addition the clinical implications and future methods by which radiologists may improve these are outlined relative to TNM8.

Impact of extranodal tumor deposits on prognosis and N stage in gastric cancer

BACKGROUND

Extranodal tumor deposits have been reported to be associated with a poor prognosis in many malignancies and are also included in the tumor, node, and metastasis staging system for colorectal cancer.

METHODS

We reviewed retrospectively a total of 2,344 gastric cancer patients who underwent gastrectomy with curative intent at the Tianjin Medical University Cancer Institute and Hospital (Hexi District, Tianjin, China) and the First Affiliated Hospital of Hainan Medical University (Longhua District, Haikou, China). Patients were categorized into 2 groups based on extranodal tumor deposit status: a positive group, including those with extranodal tumor deposits, and a negative group composed of those with no extranodal tumor deposits. Clinicopathologic factors were correlated with extranodal tumor deposits, and their individual prognoses were analyzed. In addition, a pathologically modified node classification system was proposed by incorporating the extranodal tumor deposit status into the 8th ed of the N staging system. The superiority of prognostic prediction between the modified node classification and node stage was compared.

RESULTS

A total of 645 (27.5%) patients had extranodal tumor deposits. The presence of extranodal tumor deposits was associated with a larger tumor size, Borrmann type III and IV, a deeper depth of invasion, and an advanced node stage. In the multivariate analysis, extranodal tumor deposits were an independent prognostic factor for gastric cancer patients after curative resection. Gastric cancer patients with extranodal tumor deposits demonstrated a lesser 5-year overall survival than those with no extranodal tumor deposits (31.9% vs 61.4%, P < .001). With the strata analysis, statistically significant prognostic differences between the two groups were only observed in patients at the N0-N2 stage. The modified node classification was found to be more appropriate for predicting the overall survival of gastric cancer patients after curative resection than node stage, and the -2 log likelihood of the modified node classification (16,042.890) was smaller than the value of node stage (16,150.811).

CONCLUSION

Extranodal tumor deposits in gastric cancer patients indicate aggressive characteristics and a poorer prognosis of gastric cancer. We maintain that extranodal tumor deposits should be incorporated into the N staging system to enhance the accuracy of the prognostic prediction of patients with gastric cancer.

Tumour deposits are a significant prognostic factor in gastric cancer - a systematic review and meta-analysis

AIMS

Tumour deposits (TDs) are clusters of cancer cells in the soft tissue that are discontinuous from the primary tumour. In this review we are exploring their relevance for prognosis in patients with gastric cancer.

METHODS AND RESULTS

A literature search was performed to identify studies providing data on TDs and prognosis in gastric cancer patients. Eight papers were included in the meta-analysis, which was carried out in terms of risk ratios (RR) and hazard ratios (HR) with 95% confidence interval (95% CI). Of 7445 patients, 1551 had TDs (20.9%). TDs were associated with a decreased overall survival (OS) in univariate (HR = 2.82, 95% CI = 1.9-4.3) and multivariate analyses (HR = 1.65, 95% CI = 1.3-2.1). TDs were also associated with known prognostic factors such as synchronous metastatic disease (RR = 9.5), invasion depth (RR = 1.8), lymph node metastasis (RR = 1.7), lymphatic invasion (RR = 1.7), vascular invasion (RR = 2.6) and poor differentiation (RR = 1.2).

CONCLUSIONS

We found a strong indication that TDs are independent predictors of prognosis in patients with gastric cancer; hence, TDs should be included in the staging of gastric cancers.

M51R and Delta-M51 matrix protein of the vesicular stomatitis virus induce apoptosis in colorectal cancer cells

Colorectal cancer (CRC) is the third most common cancer in both men and women. Oncolytic viral-based therapy methods seem to be promising for CRC treatment. Vesicular stomatitis virus (VSV) is considered as a potent candidate in viral therapy for several tumors. VSV particles with mutated matrix (M) protein are capable of initiating cell death cascades while not being harmful to the immune system. In the current study, the effects of the VSV M-protein was investigated on the apoptosis of the colorectal cancer SW480 cell. Wild-type, M51R, and ΔM51 mutants VSV M-protein genes were cloned into the PCDNA3.1 vector and transfected into the SW480 cells. The results of the MTT assay, Western blotting, and Caspase 3, 8, and 9 measurement, illustrated that both wild and M51R mutant M-proteins can destroy the SW480 colorectal cancer cells. DAPI/TUNEL double-staining reconfirmed the apoptotic effects of the M-protein expression. The ΔM51 mutant M-protein is effective likewise M51R, somehow it can be considered as a safer substitution.

Poor prognostic and staging value of tumor deposit in locally advanced rectal cancer with neoadjuvant chemoradiotherapy

Tumor deposit (TD) was associated with poor survival in colorectal cancer. However, its prognostic and staging value in locally advanced rectal cancer (LARC) patients following neoadjuvant chemoradiotherapy (neo‐CRT) is controversial. Four hundred and ninety‐five LARC patients following neo‐CRT and surgery were retrospectively analyzed. Univariate and multivariate analyses were performed using Kaplan‐Meier method and Cox proportional hazards regression in all lymph node (LN) ‐negative and LN‐positive patients. Next, we used three methods to classify the counts of LNs and TDs (oN, only LN counts; n1N, counts according to the N1c standards; n2N, total counts of LNs and TDs) to evaluate the impact of TD on N staging. TD‐positive patients were associated with more aggressive clinicopathological features. In multivariate analyses, TD was an independent poor prognostic factor of overall survival (OS), disease‐free survival (DFS), and local recurrence‐free survival in all patients. In LN‐negative patients, TD was an independent poor prognostic factor of OS, DFS and distant metastasis‐free survival (DMFS). In LN‐positive patients, TD has poor prognostic value only in patients with one positive LN. Three multivariate analyses according to three N staging methods showed that oN was not an independent prognostic factor, whereas n1N and n2N were independently associated with poor survival in OS, DFS and DMFS. The n2N method seemed to be better than n1N method. TD is an independent poor prognostic factor in LARC patients following neo‐CRT, especially in patients with no more than one positive LN. TD probably should be considered as one positive LN when performing N staging.

A Review of Current Challenges in Colorectal Cancer Reporting

Context.—

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

Objective.—

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

Data Sources.—

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

Conclusions.—

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