Perineural Invasion Predicts for Distant Metastasis in Locally Advanced Rectal Cancer Treated With Neoadjuvant Chemoradiation and Surgery

The value of machine learning based on CT radiomics in the preoperative identification of peripheral nerve invasion in colorectal cancer: a two-center study

BACKGROUND

We aimed to explore the application value of various machine learning (ML) algorithms based on multicenter CT radiomics in identifying peripheral nerve invasion (PNI) of colorectal cancer (CRC).

METHODS

A total of 268 patients with colorectal cancer who underwent CT examination in two hospitals from January 2016 to December 2022 were considered. Imaging and clinicopathological data were collected through the Picture Archiving and Communication System (PACS). The Feature Explorer software (FAE) was used to identify the peripheral nerve invasion of colorectal patients in center 1, and the best feature selection and classification channels were selected. Finally, the best feature selection and classifier pipeline were verified in center 2.

RESULTS

The six-feature models using RFE feature selection and GP classifier had the highest AUC values, which were 0.610, 0.699, and 0.640, respectively. FAE generated a more concise model based on one feature (wavelet-HLL-glszm-LargeAreaHighGrayLevelEmphasis) and achieved AUC values of 0.614 and 0.663 on the validation and test sets, respectively, using the "one standard error" rule. Using ANOVA feature selection, the GP classifier had the best AUC value in a one-feature model, with AUC values of 0.611, 0.663, and 0.643 on the validation, internal test, and external test sets, respectively. Similarly, when using the "one standard error" rule, the model based on one feature (wave-let-HLL-glszm-LargeAreaHighGrayLevelEmphasis) achieved AUC values of 0.614 and 0.663 on the validation and test sets, respectively.

CONCLUSIONS

Combining artificial intelligence and radiomics features is a promising approach for identifying peripheral nerve invasion in colorectal cancer. This innovative technique holds significant potential for clinical medicine, offering broader application prospects in the field.

CRITICAL RELEVANCE STATEMENT

The multi-channel ML method based on CT radiomics has a simple operation process and can be used to assist in the clinical screening of patients with CRC accompanied by PNI.

KEY POINTS

• Multi-channel ML in the identification of peripheral nerve invasion in CRC. • Multi-channel ML method based on CT-radiomics can detect the PNI of CRC. • Early preoperative identification of PNI in CRC is helpful to improve the formulation of treatment strategies and the prognosis of patients.

Differential clinical outcomes after 3 versus 5 years in a comparison of preoperative chemotherapy with and without radiotherapy in locally advanced rectal cancer: A national cohort propensity score-matched study

Background

Preoperative chemotherapy alone might be a good alternative to preoperative chemoradiotherapy for patients with locally advanced rectal cancer, yet long-term real-world data from the same cohort are lacking.

Methods

Patients diagnosed with stage II-III rectal adenocarcinoma from 2011 to 2015 were randomly sampled from the SEER-Plus database to evaluate the superiority of preoperative chemoradiotherapy versus preoperative chemotherapy alone.

Findings

A total of 1314 eligible patients were enrolled, with a median follow-up of 74.0 months. At 3-year follow-up, neither overall survival (OS) nor cancer-specific survival (CSS) was significantly different between the two treatment groups. At 5-year follow-up, CSS was similar across groups (HR 0.768, 95% CI 0.532-1.108; P = 0.156), but the 5-year OS was significantly better in the preoperative chemoradiotherapy group than in the preoperative chemotherapy group (HR 0.682, 95% CI 0.538-0.866; P = 0.002). Besides, the landmark analysis indicated a direct contrast in the CSS within 3 years (HR 1.101, 95% CI 0.598-2.029; P = 0.756) versus that at 3-5 years (HR 0.597, 95% CI 0.377-0.948; P = 0.027). The landmark analysis also showed directly contrasting OS outcomes within 3 years (HR 0.761, 95% CI 0.533-1.086; P = 0.130) versus those at 3-5 years (HR 0.621, 95% CI 0.451-0.857; P = 0.003).

Interpretation

In patients with locally advanced rectal cancer under real-world treatment practices, the addition of preoperative radiotherapy to chemotherapy improves survival outcomes at 3-5 years' follow-up but not at 3-year follow-up.

Prediction of liver metastasis and recommended optimal follow-up nursing in rectal cancer

We aimed to analyze and investigate the clinical factors that influence the occurrence of liver metastasis in locally advanced rectal cancer patients, with an attempt to assist patients in devising the optimal imaging-based follow-up nursing. Between June 2011 and May 2021, patients with rectal cancer at our hospital were retrospectively analyzed. A random survival forest model was developed to predict the probability of liver metastasis and provide a practical risk-based approach to surveillance. The results indicated that age, perineural invasion, and tumor deposit were significant factors associated with the liver metastasis and survival. The liver metastasis risk of the low-risk group was higher at 6-21 months, with a peak occurrence time in the 15th month. The liver metastasis risk of the high-risk group was higher at 0-24 months, with a peak occurrence time in the 8th month. In general, our clinical model could predict liver metastasis in rectal cancer patients. It provides a visualization tool that can aid physicians and nurses in making clinical decisions, by detecting the probability of liver metastasis.

Development and validation of a combined nomogram for predicting perineural invasion status in rectal cancer via computed tomography-based radiomics

AIM

This study aimed to create and validate a clinic-radiomics nomogram based on computed tomography (CT) imaging for predicting preoperative perineural invasion (PNI) of rectal cancer (RC).

MATERIAL AND METHODS

This study enrolled 303 patients with RC who were divided into training (n = 242) and test datasets (n = 61) in an 8:2 ratio with all their clinical outcomes. A total of 3,296 radiomic features were extracted from CT images. Five machine learning (ML) models (logistic regression (LR)/K-nearest neighbor (KNN)/multilayer perceptron (MLP)/support vector machine (SVM)/light gradient boosting machine (LightGBM)) were developed using radiomic features derived from the arterial and venous phase images, and the model with the best diagnostic performance was selected. By combining the radiomics and clinical signatures, a fused nomogram model was constructed.

RESULTS

After using the Mann-Whitney U-test and least absolute shrinkage and selection operator (LASSO) to remove redundant features, the MLP model proved to be the most efficient among the five ML models. The fusion nomogram based on MLP prediction probability further improves the ability to predict the PNI status. The area under the curve (AUC) of the training and test sets was 0.883 and 0.889, respectively, which were higher than those of the clinical (training set, AUC = 0.710; test set, AUC = 0.762) and radiomic models (training set, AUC = 0.840; test set, AUC = 0.834).

CONCLUSIONS

The clinical-radiomics combined nomogram model based on enhanced CT images efficiently predicted the PNI status of patients with RC.

The Incidence of Lymphovascular and Perineural Invasion and their Impact on Survival in Patients with Rectal Cancer

Aim: Lymphovascular Invasion (LVI) and Perineural Invasion (PNI) represent undesirable but still realistic pathological features of rectal cancer, associated with poor prognosis and worse survival. The aim of this study is to assess the incidence of LVI and PNI in patients treated for rectal cancer and the impact of LVI and PNI on patient survival. Material and Methods: This retrospective single center observational study, conducted in the period of 2016-2019, includes patients with rectal cancer treated with/without long-course neoadjuvant chemoradiotherapy (nCRT). Data collection encompassed demographics, tumor characteristics, type of surgery (abdominal perineal rectal resection - APR and low anterior rectal resection - LAR), and LVI/PNI presence. Survival during follow-up was estimated and compared for patients with/without LVI and PNI involvement. Results: A total number of 234 patients (77 females and 157 males) with mean age of 61.3 enrolled in the study. Neoadjuvant CRT was conducted in 170 patients. APR procedure was performed in 67 of them and LAR in 167. LVI presence was noted in 55 (24.4%) and PNI in 77 (34.2%) patients. Mean survival during follow-up was 42.07 months. The use of nCRT influenced on survival (p < 0.033). Patients treated with LAR had better survival outcomes (p = 0.001). Presence of LVI and PNI was associated with a worse prognosis (p < 0.001). Conclusion: PNI was more frequent than the LVI in this study. Patients with nCRT conduction had better overall survival. LVI and PNI presence was associated with poor prognosis in terms of overall survival in patients with rectal cancer.

Risk-factors for locally advanced rectal cancer relapse after neoadjuvant chemoradiotherapy: A single center experience

The overall prognosis of locally advanced rectal cancer (LARC) remains unsatisfactory due to a high incidence of disease relapse. The present understanding of the factors that determine the likelihood of recurrence is limited or ineffective. We aimed to identify the main risk factors influencing tumor relapse in LARC patients after neoadjuvant chemoradiotherapy (nCRT) and surgical treatment in a single center in Republika Srpska. Patients with stage II or stage III who received nCRT before surgery for primary rectal cancer at the Oncology Clinic, University Clinical Center of Republika Srpska from January 2017 and December 2022 were included in the study. We collected patient demographics, clinical stage and characteristics, neoadjuvant therapy, and surgical methods, along with the pathological response after treatment completion, and analyzed them to identify the risk factors for tumor relapse. Out of 109 patients diagnosed with LARC, 34 (31,2%) had tumor relapse. The median time to relapse was 54 months. Participants with clinical T4 stage had a significantly shorter relapse time compared to the patients with clinical T2/3 stage. Subjects with positive lymph nodes removed, perivascular and perineural invasion, intraoperative perforation and patients without ypN stage improvement had significantly shorter time to relapse. Subjects with T4 stage had more than 4 times higher risk of relapse than patients with clinical T2/3 stage. Higher clinical T stage was an essential risk factor for tumor relapse in LARC patients after nCRT and surgical treatment. Comprehensive understanding and identification of the risk factors for tumor relapse in LARC patients are crucial for improving their long-term outcomes.

Prognostic impact of lymphovascular and perineural invasion in squamous cell carcinoma of the tongue

This study aimed to investigate the prognostic impact of lymphovascular and perineural invasions in patients with squamous cell carcinoma of the tongue who received surgery-based treatment at our institution between January 2013 and December 2020. Patients were divided into four groups based on the presence of perineural (P-/P +) and lymphovascular invasions (V-/V +): P-V-, P-V + , P + V-, and P + V + . Log-rank and Cox proportional hazard models were used to evaluate the association between perineural /lymphovascular invasion and overall survival (OS). Altogether, 127 patients were included, and 95 (74.8%), 8 (6.3%), 18 (14.2%), and 6 (4.7%) cases were classified as P-V-, P-V + , P + V-, and P + V + , respectively. Pathologic N stage (pN stage), tumor stage, histological grade, lymphovascular invasion, perineural invasion, and postoperative radiotherapy were significantly associated with OS (p < 0.05). OS was significantly different among the four groups (p < 0.05). Significant between-group differences in OS were detected for node-positive (p < 0.05) and stage III-IV (p < 0.05) cases. OS was the worst in the P + V + group. Lymphovascular and perineural invasions are independent negative prognostic factors for squamous cell carcinoma of the tongue. Patients with lymphovascular and/or perineural invasion may have significantly poorer overall survival than those without neurovascular involvement.

Clinical Implication of Perineural and Lymphovascular Invasion in Rectal Cancer Patients Who Underwent Surgery After Preoperative Chemoradiotherapy

BACKGROUND

Lymphovascular and perineural invasion are well-known negative prognostic indicators in rectal cancer, but previous studies on their significance are not consistent.

OBJECTIVE

This study assessed the prognostic value of lymphovascular and perineural invasion in rectal cancer patients who received preoperative chemoradiotherapy followed by curative resection.

DESIGN

This is a retrospective analysis.

SETTING

This study was performed at a tertiary cancer center.

PATIENTS

Rectal cancer patients who underwent curative resection after preoperative chemoradiotherapy between January 2000 and December 2010.

MAIN OUTCOME MEASURES

The primary outcomes were disease-free survival and overall survival. The survival rates were estimated using Kaplan-Meier analysis, and group comparisons were conducted using a log-rank test.

RESULTS

Of the 1156 included patients, 109 (9.4%) presented with lymphovascular invasion and 137 (11.9%) presented with perineural invasion. Lymphovascular and perineural invasion were associated with T and N downstaging after preoperative chemoradiotherapy ( p < 0.001). In the ypN0 patients, the 5-year disease-free survival rates were 70.8% and 78.5% ( p = 0.150) for the lymphovascular invasion and absent groups, respectively. In the perineural invasion group, the 5-year disease-free survival rate was 59.0% compared to 80.2% in the absent group ( p = 0.001). Among the ypN+ patients, the 5-year disease-free survival rates were 36.9% and 44.4% for the lymphovascular invasion and absent groups, respectively ( p = 0.211). The perineural invasion group had a poorer 5-year disease-free survival rate compared to the absent group (29.7% vs 46.7%; p = 0.011). By multivariable analyses, perineural invasion correlated with a poor disease-free survival (HR 1.412, 95% CI 1.082-1.843; p = 0.011) and also in ypN0 subgroup analysis (HR 1.717, 95% CI 1.093-2.697; p = 0.019).

LIMITATIONS

This study was a retrospective study conducted at a single center.

CONCLUSIONS

Perineural invasion is a reliable independent predictor of recurrence in rectal cancer patients treated with preoperative chemoradiotherapy. Patients with perineural invasion should be considered for closer surveillance even with ypN0 status. See Video Abstract at http://links.lww.com/DCR/B833 .IMPLICACIÓN CLÍNICA DE LA INVASIÓN PERINEURAL Y LINFOVASCULAR EN PACIENTES CON CÁNCER DE RECTO SOMETIDOS A CIRUGÍA DESPUÉS DE QUIMIORRADIOTERAPIA PREOPERATORIA.

ANTECEDENTES

La invasión linfovascular y perineural en cancer de recto, son indicadores pronósticos negativos bien conocidos, pero estudios previos sobre su significancia, no son consistentes.

OBJETIVO

El estudio evaluó el valor pronóstico de la invasión linfovascular y perineural en pacientes con cáncer de recto sometidos a quimiorradioterapia preoperatoria seguida de resección curativa.

DISEO

Es un análisis retrospectivo.

ENTORNO CLINICO

El estudio se realizó en un centro oncológico terciario.

PACIENTES

Pacientes con cáncer de recto sometidos a resección curativa después de quimiorradioterapia preoperatoria entre enero de 2000 y diciembre de 2010.

PRINCIPALES MEDIDAS DE VALORACION

Los resultados primarios fueron la supervivencia libre de enfermedad y la supervivencia general. Las tasas de supervivencia se estimaron mediante el análisis de Kaplan-Meier y las comparaciones de grupos se realizaron mediante una prueba de rango logarítmico.

RESULTADOS

De los 1156 pacientes incluidos, 109 (9,4%) presentaron invasión linfovascular y 137 (11,9%) invasión perineural. La invasión linfovascular y perineural se asoció con reducción del estadio de T y N después de la quimiorradioterapia preoperatoria ( p < 0,001). En los pacientes ypN0, las tasas de supervivencia libre de enfermedad a 5 años fueron del 70,8% y el 78,5% ( p = 0,150) para los grupos con y sin invasión linfovascular, respectivamente. En el grupo de invasión perineural, la tasa de supervivencia libre de enfermedad a 5 años fue del 59,0%, en comparación con el 80,2% en el grupo ausente ( p = 0,001). Entre los pacientes ypN +, las tasas de supervivencia sin enfermedad a 5 años fueron del 36,9% y 44,4% para los grupos con y sin invasión linfovascular, respectivamente ( p = 0,211). El grupo de invasión perineural mostró una tasa de supervivencia libre de enfermedad a 5 años menor, en comparación con el grupo ausente (29,7% versus 46,7%, p = 0,011). Mediante análisis multivariable, la invasión perineural se correlacionó con una pobre tasa de supervivencia de enfermedad (índice de riesgo 1,412; intervalo de confianza del 95%: 1,082-1,843; p = 0,011) y también en el análisis de subgrupos ypN0 (índice de riesgo 1,717; intervalo de confianza del 95%: 1,093-2,697; p = 0,019).

LIMITACIONES

Estudio retrospectivo realizado en un solo centro.

CONCLUSIONES

La invasión perineural es un predictor independiente y confiable de recurrencia en pacientes con cáncer de recto tratados con quimiorradioterapia preoperatoria. Los pacientes con invasión perineural deben considerarse para una vigilancia más estrecha incluso con estadio ypN0. Consulte Video Resumen en http://links.lww.com/DCR/B833 . (Traducción-Dr. Fidel Ruiz Healy ).

The Nervous System as a Regulator of Cancer Hallmarks: Insights into Therapeutic Implications

Simple Summary

The nervous system communicates with the whole organism, regulating several physiological pathways. The modification of nerve activity could deregulate the state of cellular and tissue homeostasis which could drive cancer development. This paper provides the current state of knowledge, in an evidence-oriented manner, that the nervous system is able to participate in the carcinogenesis process by inducing biochemical, physiological, and cellular modifications involved in the hallmarks of cancer.

Abstract

The involvement of the nervous system in the development of cancer is controversial. Several authors have shown opinions and conflicting evidence that support the early effect of the nervous system on the carcinogenic process. For about a century, research has not been enough, questions remain open, ideas are not discarded, and although more research is still needed to answer all the questions, there is now enough evidence to support the theories and give hope of finding one more possible form of treatment. It is clear that malignant neoplasms have endogenous characteristics that allow them to establish and progress. Some of these characteristics known as hallmarks of cancer, are damage mechanisms in the pathology but necessary during other physiological processes which show some nerve dependence. The nervous system communicates with the whole organism, regulating physiological processes necessary to respond to external stimuli and for the maintenance of homeostasis. The modification of nerve activity could generate an overload and deregulate the state of cellular and tissue homeostasis; this could drive cancer development. In this review, we will address the issue in an evidence-oriented manner that supports that the nervous system is able to participate in the initial and progressive process of carcinogenesis by inducing biochemical, physiological, and cellular modifications involved in the hallmarks of cancer.

Pathologic Implications of Radial Resection Margin and Perineural Invasion to Adjuvant Chemotherapy after Preoperative Chemoradiotherapy and Surgery for Rectal Cancer: A Multi-Institutional and Case-Matched Control Study

We assessed the exact role of adjuvant chemotherapy after neoadjuvant chemoradiotherapy (CRT) and surgery in rectal cancer patients with positive surgical margin or perineural invasion (PNI). This multi-institutional study included 1799 patients with rectal cancer at cT3-4N0-2M0 stages. Patients were divided into two groups. The high-risk group had a positive margin and/or perineural invasion. The low-risk group showed no positive margin or PNI. Propensity-score matching analysis was performed, and a total of 928 patients, with 464 in each arm, were evaluated. The high-risk group showed significant differences in overall survival (OS, 73.4% vs. 53.9%, p < 0.01) and recurrence-free survival (RFS, 52.7% vs. 40.9%, p = 0.01) at five years between the adjuvant chemotherapy arm and observation arm. The low-risk group showed no significant differences in 5-year OS (p = 0.61) and RFS (p = 0.75) between the two arms. Multivariate analyses showed that age, pathologic N stage, and adjuvant chemotherapy were significantly correlated with OS and RFS in the high-risk group (all p < 0.05). Adjuvant chemotherapy improved OS and RFS more significantly in rectal cancer patients with positive surgical margin or PNI than in those with negative surgical margin and PNI.

Preoperative Prediction of Perineural Invasion Status of Rectal Cancer Based on Radiomics Nomogram of Multiparametric Magnetic Resonance Imaging

Objectives

To compare the predictive performance of different radiomics signatures from multiparametric magnetic resonance imaging (mpMRI), including four sequences when used individually or combined, and to establish and validate an optimal nomogram for predicting perineural invasion (PNI) in rectal cancer (RC) patients.

Methods

Our retrospective study included 279 RC patients without preoperative antitumor therapy (194 in the training dataset and 85 in the test dataset) who underwent preoperative mpMRI scan between January 2017 and January 2021. Among them, 72 cases were PNI-positive. Then, clinical and radiological variables were collected, including carcinoembryonic antigen (CEA), radiological tumour stage (T_1-4), lymph node stage (N_0-2) and so on. Quantitative radiomics features were extracted and selected from oblique axial T₂-weighted imaging (T₂WI), T₁-weighted imaging (T₁WI), apparent diffusion coefficient (ADC), and enhanced T₁WI (T₁CE) sequences. The clinical model was constructed by integrating the final selected clinical and radiological variables. The radiomics signatures included four single-sequence signatures and one fusion signature were built using the respective remaining optimized features. And the nomogram was constructed based on the independent predictors by using multivariable logistic regression. The area under curve (AUC), DeLong test, calibration curve, and decision curve analysis (DCA) were used to evaluate the performance.

Results

Ultimately, 20 radiomics features were retained from the four sequences—T₁WI (n = 4), T₂WI (n = 5), ADC (n = 5), and T₁CE (n = 6)—to construct four single-sequence radiomics signatures and one fusion radiomics signature. The fusion radiomics signature performed better than four single-sequence radiomics signatures and clinical model (AUCs of 0.835 and 0.773 vs. 0.680-0.737 and 0.666-0.709 in the training and test datasets, respectively). The nomogram constructed by incorporating CEA, tumour stage and rad-score performed best, with AUCs of 0.869 and 0.864 in the training and test datasets, respectively. Delong test showed that the nomogram was significantly different from the clinical model and four single-sequence radiomics signatures (P < 0.05). Moreover, calibration curves demonstrated good agreement, and DCA highlighted benefits of the nomogram.

Conclusions

The comprehensive nomogram can preoperatively and noninvasively predict PNI status, provide a convenient and practical tool for treatment strategy, and help optimize individualized clinical decision-making in RC patients.

Predicting response to neoadjuvant chemoradiotherapy in rectal cancer: from biomarkers to tumor models

Colorectal cancer (CRC) is a major contributor to cancer-associated morbidity worldwide and over one-third of CRC is located in the rectum. Neoadjuvant chemoradiotherapy (nCRT) followed by surgical resection is commonly applied to treat locally advanced rectal cancer (LARC). In this review, we summarize current and novel concepts of neoadjuvant therapy for LARC such as total neoadjuvant therapy and describe how these developments impact treatment response. Moreover, as response to nCRT is highly divergent in rectal cancers, we discuss the role of potential predictive biomarkers. We review recent advances in biomarker discovery, from a clinical as well as a histopathological and molecular perspective. Furthermore, the role of emerging predictive biomarkers derived from the tumor environment such as immune cell composition and gut microbiome is presented. Finally, we describe how different tumor models such as patient-derived cancer organoids are used to identify novel predictive biomarkers for chemoradiotherapy (CRT) in rectal cancer.

Preoperative prediction of perineural invasion with multi-modality radiomics in rectal cancer

Perineural invasion (PNI) as a grossly underreported independent risk predictor in rectal cancer is hard to identify preoperatively. We aim to predict PNI status in rectal cancer using multi-modality radiomics. In total, 396 radiomics features were extracted from T2-weighted images (T2WIs), diffusion-weighted images (DWIs), and portal venous phase of contrast-enhanced CT (CE-CT) respectively of 94 consecutive patients with histologically confirmed rectal cancer. T2WI score, DWI score, and CT score were calculated via the radiomics features selection and optimization. Discrimination, calibration, and clinical benefit ability were used to evaluate the performance of the radiomics scores in both training and testing datasets. CT score and T2WI score were independent risk predictors [CT score, OR (95% CI) = 4.218 (1.070-16.620); T2WI score, OR (95% CI) = 105.721 (3.091-3615.790)]. The concise score which combined CT score and T2WI score, showed the best performance [training dataset, AUC (95% CI) = 0.906 (0.833-0.979); testing dataset, AUC (95% CI) = 0.884 (0.761-1.000)] and good calibration (P > 0.05 in the Hosmer-Lemeshow test for the training and testing datasets). Decision curve analysis showed that the multi-modality radiomics nomogram had a higher clinical net benefit. The multi-modality radiomics score could be used to preoperatively assess PNI status in rectal cancer.

Perineural invasion as a predictive factor for survival outcome in gastric cancer patients: a systematic review and meta-analysis

AIMS

The prognostic significance of perineural invasion (PNI) for gastric cancer (GC) patients was under debate. This study aimed to review relevant studies and evaluate the impact of PNI on the survival outcome of GC patients.

METHODS

Systematic literature search was performed using PubMed and Embase databases. The relevant data were extracted, and the association between PNI and clinicopathological characteristics or survival outcome in GC patients were evaluated using a fixed-effect model or random-effect model.

RESULTS

A total 13 studies involving 7004 GC patients were included in this meta-analysis. The positive rate of PNI was 35.9% (2512/7004) in GC patients, ranging from 6.9% to 75.6%. There were significant relationships between PNI and a series of unfavourable clinicopathological factors including undifferentiated histology type (OR: 1.78, 95% CI 1.37 to 2.33, p<0.001; I²=75.3%), diffuse type (OR: 1.96, 95% CI 1.07 to 3.60, p=0.029; I²=79.5%), lymphatic invasion (OR: 7.00, 95% CI 3.76 to 13.03, p<0.001; I²=83.6%), vascular invasion (OR: 5.79, 95% CI 1.59 to 21.13, p=0.008; I²=95.8%), deeper tumour invasion (OR: 4.79, 95% CI 3.65 to 6.28, p<0.001; I²=65.0%) and lymph node metastasis (OR: 3.60, 95% CI 2.37 to 5.47, p<0.001; I²=89.6%). In addition, PNI was significantly associated with worse survival outcome in GC patients (HR: 1.69, 95% CI 1.38 to 2.06, p<0.001; I²=71.0%).

CONCLUSION

PNI was frequently detected in surgically resected specimens of GC patients, and it was a predictive factor for survival outcomes in these patients.

Perineural and lymphovascular invasion predicts for poor prognosis in locally advanced rectal cancer after neoadjuvant chemoradiotherapy and surgery

Background: Perineural invasion (PNI) and lymphovascular invasion (LVI) are associated with poor prognosis in colorectal cancer, but their clinical significance is still controversial for patients with locally advanced rectal cancer (LARC) who had received neoadjuvant chemoradiotherapy (nCRT) and surgical resection. The aim of this study was to confirm the correlation between PNI and/or LVI and clinical prognosis and to further confirm whether PNI and/or LVI can be used as potential prognostic indicators of adjuvant chemotherapy after nCRT and surgery in LARC.

Methods: From February 2002 to December 2012, a total of 181 patients with LARC who had received nCRT and surgical resection were retrospectively reviewed. Overall survival (OS) and disease-free survival (DFS) were determined by the Kaplan-Meier method, log-rank test, and Cox proportional hazard regression model.

Results: The median follow-up time was 48 months (range, 3 to 162 months). All the PNI-positive and/or LVI-positive patients showed adverse DFS and OS (P<0.001). In multivariate analysis, PNI and LVI were independent prognostic factors for DFS. PNI, rather than LVI, was also an independent prognostic factor for OS. In a subgroup analysis, PNI-positive, rather than LVI-positive, may benefit from adjuvant chemotherapy.

Conclusion: For patients with LARC undergoing nCRT and surgery, PNI-positive and/or LVI positive were associated with poorer DFS and OS. And PNI-positive, rather than LVI-positive, may benefit from adjuvant chemotherapy.

Prognostic Impact of Perineural Invasion in Rectal Cancer After Neoadjuvant Chemoradiotherapy

BACKGROUND

Perineural invasion (PNI) has emerged as an important factor related to colorectal cancer spread; however, the impact of neoadjuvant chemoradiotherapy (nCRT) on PNI remains unclear. Herein, we investigated the prognostic value of PNI, along with lymphovascular invasion (LVI), in rectal cancer patients treated with nCRT.

METHODS

This single-center observational study of pathologic variables, including PNI and LVI, analyzed 1411 invasive rectal cancer patients (965 and 446 patients treated with primary resection and nCRT, respectively).

RESULTS

The overall detection rates of LVI and PNI were 16.7 and 28.8%, respectively. The incidence of LVI was significantly lower in patients treated with nCRT (8.1 vs. 20.6%, P < .001); this was confirmed by multivariate analysis. However, PNI was not affected by nCRT (with nCRT 28.3% vs. without nCRT 29.1%, P = .786). In the 446 patients with nCRT, multivariate analysis revealed that PNI was an independent prognostic factor for both disease-free survival (DFS) and overall survival (OS). For the prediction of both 5-year DFS and OS, the C-index for the combinations of T-stage with the PNI (TPNI) system showed favorable result, especially in patients with a total number of harvested lymph nodes <8.

CONCLUSION

PNI is a meaningful prognostic factor for rectal cancer patients treated with nCRT, especially when <8 lymph nodes are harvested. The lack of influence of nCRT on the PNI incidence suggests that residual tumor cells with PNI are more radioresistant or biologically aggressive than those without.

Histopathological Analysis of 173 Consecutive Patients with Colorectal Carcinoma: A Pathologist's View

Background

Worldwide, colorectal carcinomas are the third most common carcinomas in men and the second most common carcinomas in women. Pathological examination of rectum specimens requires special attention for correctly evaluating many prognostically important factors. In this study, we present pathological results of 173 lower anterior resection (LAR) and abdominoperineal resection (APR) specimens retrospectively evaluated.

Material/Methods

We included 173 LAR and APR specimens in this study. Patients were evaluated in the Istanbul Ekin Private Pathology Laboratory and underwent surgery at Çanakkale State Hospital, General Surgery Clinic.

Results

Of the 173 specimens, 15 (8.7%) were APR and 158 (91.3%) were LAR specimens. Ninety-four patients (54.3%) were males and 79 patients (45.7%) were females. The mean age of the patients was 63.5 years (range 26–90 years). In the histopathological examination, malignant neoplasm was detected in 172 of the cases (99.4%) and benign endometriosis was detected in 1 of the cases (0.6%). There were 151 (87.2%), 8 (4.6%), 5 (2.9%), 1 (0.6%), 1 (0.6%), 1 (0.6%), 1 (0.6%), 1 (0.6%), and 4 (2.3%) patients with adenocarcinoma, mucinous adenocarcinoma, intramucosal adenocarcinoma in the setting of a high-grade tubulovillous adenoma, synchronous colon/prostate adenocarcinoma, malignant melanoma, signet ring cell carcinoma, gastrointestinal stromal tumor, endometriosis, and adenocarcinoma diagnosed by the examination of colonoscopic biopsy specimens that showed complete regression with neoadjuvant therapy, respectively.

Conclusions

When evaluating specimens from patients with colorectal carcinoma, pathological evaluation, which is one of the most fundamental pillars in managing patients with cancer, must be performed carefully and meticulously. Each pathological parameter should be evaluated carefully and clinicians and pathologists should evaluate these cases together.

Patterns of recurrence in oral tongue cancer with perineural invasion

BACKGROUND

Although perineural invasion (PNI) is recognized as an adverse prognostic factor in oral tongue squamous cell carcinoma (SCC), the patterns of failure are poorly defined.

METHODS

Patients with oral tongue SCC who received primary surgical treatment were identified. Specimens were reviewed by head and neck pathologists. Disease-specific survival (DSS) and locoregional recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), and distant recurrence-free survival (DRFS) were calculated. The PNI and PNI characteristics were analyzed as predictors of outcome. The utility of grading the extent of PNI was assessed by quantifying the number of PNI foci per slide reviewed, nerve caliber, and percent circumference involved.

RESULTS

Patients with PNI had a decreased DSS; however, PNI was not predictive of LRFS or RRFS. Patients with PNI were more likely to develop a distant recurrence and 19.40 (confidence interval [CI] 6.70-56.14; P < .001) times more likely to develop a distant recurrence if PNI foci density was >1.

CONCLUSION

The presence of PNI in oral tongue SCC predicts worse DSS, with distant recurrence as the most common pattern of failure. High PNI foci density is associated with worse DRFS.

Tailored Treatment of Colorectal Cancer: Surgical, Molecular, and Genetic Considerations

Colorectal cancer (CRC) is a complex cancer disease, and approximately 40% of the surgically cured patients will experience cancer recurrence within 5 years. During recent years, research has shown that CRC treatment should be tailored to the individual patient due to the wide variety of risk factors, genetic factors, and surgical complexity. In this review, we provide an overview of the considerations that are needed to provide an individualized, patient-tailored treatment. We emphasize the need to assess the predictors of CRC, and we summarize the latest research on CRC genetics and immunotherapy. Finally, we provide a summary of the significant variations in the colon and rectal anatomy that is important to consider in an individualized surgical approach. For the individual patient with CRC, a tailored treatment approach is needed in the preoperative, operative, and postoperative phase.