Tumor regression grades: Potential outcome predictor of locally advanced rectal adenocarcinoma after preoperative radiotherapy

First clinical report of the international single-port robotic rectal cancer registry

BACKGROUND

Rectal cancer surgery remains a significant technical challenge. The development and implementation of a new technology offer hope for more accurate and precise surgery. To evaluate whether single-port robotic (SPr) technology helps achieve this goal, an international SPr registry was established. This study reported short-term clinical and oncologic outcomes from an international SPr registry for rectal cancer.

METHODS

A review of a prospective international registry of SPr technology approved for colorectal surgery with an investigational design exemption was conducted. Patients with rectal adenocarcinoma who had resection for curative intent using the SPr platform between November 2018 and September 2022 were included. Frequency statistics described patient and tumor characteristics and intraoperative, oncologic, and clinical outcome variables. The main outcome measure was the quality of the total mesorectal excision (TME) specimen. The secondary outcome measures were intraoperative conversion and 30-day postoperative morbidity and mortality.

RESULTS

A total of 113 SPr procedures for rectal cancer were performed at 2 centers by 4 colorectal surgeons. Of note, 9 local excisions were excluded, leaving 104 cases analyzed. The cohort consisted of 53 men (50.96%), had a mean age of 60.00 years (SD, 11.29), and had a body mass index of 25.80 kg/m2 (SD, 6.18). The most common T stage was 3 (55 [52.8%]), followed by 2 (19 [18.26%]). More than 60% of patients had preoperative neoadjuvant chemoradiation. The mean tumor distance from the anorectal ring was 2.90 cm (SD, 2.62), and the mean tumor size was 4.52 cm (SD, 1.82). The procedures performed included transanal abdominal transanal/transanal TME (52 [46%]), low anterior resection (49 [43.3%]), and abdominoperineal resection (3 [2.7%]). The mean operating time was 168.0 min (SD, 56.9). There were no intraoperative complications and 2 (1.9%) conversions to laparoscopy. There was a median of 2 incisions, with a mean size of 2.30 cm (SD, 1.31). The TME specimens were complete in 101 cases (97.1%) and near complete in 3 cases (2.9%). The R1 rate was 3.8%, with 3 positive distal margins and 1 positive circumferential margin. Postoperatively, there were 15 total complications, of which 4 were major complications and 11 were minor complications. There were 2 readmissions (ileus and small bowel obstruction). There were no mortalities.

CONCLUSION

This early international experience with the SPr procedure showed that it is a safe and effective technique for distal rectal cancers, with excellent specimen quality. The complication and conversion rates observed with other techniques and platforms used in rectal cancer surgery were not demonstrated. An international registry was used to better understand the opportunities and limitations of SPr technology in rectal cancer surgery as the technology is adopted and applied more widely. Although structured training and controlled trials will be required to develop best practices and define the use of the SPr technology, initial international registry data are encouraging.

Two Rare Cases of Metastatic Occult Thyroid Carcinoma Without Primary Cancer in the Thyroid Gland

Papillary thyroid cancer (PTC) contributes to the majority of all thyroid malignancies. In this case report, we detail two cases of occult thyroid carcinoma (OTC), which presents with thyroid metastasis to locoregional lymph nodes without having an initial primary tumor detected in the thyroid gland. OTC may be found incidentally on biopsy, surgery, or imaging. Advancements in diagnostic technology have allowed physicians to identify and treat OTC at an earlier stage. We present two patients who were found to have metastases to cervical lymph nodes without a primary identification in the thyroid gland. The first patient was a 67-year-old female who noticed an enlarging mass in her right neck at levels III and IV. Fine needle aspiration (FNA) revealed the presence of PTC. The patient underwent a total thyroidectomy, central nodal dissection, and right-modified radical neck dissection. Final pathology confirmed the presence of PTC metastasis to cervical lymph nodes, but no primary tumor was identified within the thyroid gland. The second patient was a 79-year-old male who presented with a painless mass of the left parotid gland. The FNA of the patient revealed PTC metastasis to his left parotid gland. The patient underwent a total thyroidectomy, ipsilateral central nodal dissection, ipsilateral modified radical neck dissection, and inferior superficial and deep lobe parotidectomy. No malignancy was detected within the thyroid gland or central or lateral neck lymph nodes on final pathology. Carcinoma was confined to an intra-parotid node in the deep lobe of the parotid gland. OTC is a rare phenomenon in PTC. One proposed theory for OTC includes spontaneous regression of the primary tumor and genetic mutations to the BRAF gene. Due to the fact that it is easy for this rare condition to be misdiagnosed, more studies should be conducted to standardize diagnostic and treatment plans for OTC.

Long-term survival after hepatic resection for colorectal liver metastases: a single-center study in Iran

BACKGROUND

Surgical resection of colorectal cancer liver metastasis (CRLM) has been associated with improved survival in these patients. The purpose of this study was to investigate the usefulness of liver metastasectomy, also finding independent factors related to survival after liver metastasectomy.

METHODS

In a retrospective study, all patients with CRLM who underwent resection of liver metastases between 2012 and 2022 at Imam Khomeini Hospital Complex in Tehran, Iran, were enrolled. All patients were actively followed based on clinicopathologic and operative data.

RESULTS

A total of 248 patients with a median follow-up time of 46 months (Range, 12 to 122) were studied. Eighty-six patients (35.0%) underwent major hepatectomy, whereas 160 (65.0%) underwent minor hepatectomy. The median overall survival was 43 months (Range, 0 to 122 months), with estimated 1-, 3- and 5-year overall survival rates of 91%, 56%, and 42%, respectively. Multivariate analysis demonstrated that a metastasis size > 6 cm, major hepatectomy, rectum as the primary tumor site, and involved margin (< 1 mm) were independent factors associated with decreased overall survival (OS).

CONCLUSION

Surgical resection is an effective treatment for patients with CRLM that is associated with relatively favorable survival. A negative margin of 1 mm seems to be sufficient for oncological resection.

Impact of Neoadjuvant Radiochemotherapy on Pathological Complete Response for Locally Advanced Rectal Cancer: A Mono Institutional Experience

BACKGROUND/AIM

Neoadjuvant radiochemotherapy followed by surgery is a standard of care in locally advanced rectal cancer (LARC). Only a subgroup of patients can obtain a pathological complete response (pCR) and achieve good local control. However, the role of pCR on patient survival is debated. The aim of the study was to evaluate the impact of pCR on clinical outcomes and toxicities in LARC patients treated with dose intensification and concomitant capecitabine treatment in a neoadjuvant radiochemotherapy schedule.

PATIENTS AND METHODS

This was a single Institution retrospective study including 178 patients. Mandard tumor regression grade (TRG) and pTNM staging system were used to classify pathological response and define pathological complete response (pCR). Patients were divided in: pCR (pT0N0) and Not-pCR (pT>0N>0), according to pTNM and in good responders (TRG1-2) and partial/not responders (TRG3-5), according to Mandard TRG. The Kaplan-Meier method was used to estimate OS, CSS, DFS and LC.

RESULTS

A low severe toxicity rate was observed. Acute Grade 3 lower bowel toxicity and Grade 3 cutaneous toxicity were reported in 2 (1.1%) patients, respectively. Late Grade >3 lower bowel toxicity was reported in 6 patients (3%) and late Grade >3 cutaneous toxicity was registered in one patient. No other severe acute and late toxicities were reported. The 5- and 10-year OS, CSS, DFS and LC rates were 85% and 75%, 94% and 92%, 83% and 81%, 88% and 88%, respectively. We observed a pCR rate of 36% and a good responders rate of 62%, in our study population. Both groups showed better rates for each analyzed clinical outcome.

CONCLUSION

Neoadjuvant radiochemotherapy with dose intensification in LARC patients resulted in favorable long-term oncological outcomes, pCR rate showed an optimal impact on OS and DFS with an acceptable toxicity.

Proteomic and metabolomic signatures of rectal tumor discriminate patients with different responses to preoperative radiotherapy

Background

Neoadjuvant radiotherapy (neo-RT) is widely used in locally advanced rectal cancer (LARC) as a component of radical treatment. Despite the advantages of neo-RT, which typically improves outcomes in LARC patients, the lack of reliable biomarkers that predict response and monitor the efficacy of therapy, can result in the application of unnecessary aggressive therapy affecting patients' quality of life. Hence, the search for molecular biomarkers for assessing the radio responsiveness of this cancer represents a relevant issue.

Methods

Here, we combined proteomic and metabolomic approaches to identify molecular signatures, which could discriminate LARC tumors with good and poor responses to neo-RT.

Results

The integration of data on differentially accumulated proteins and metabolites made it possible to identify disrupted metabolic pathways and signaling processes connected with response to irradiation, including ketone bodies synthesis and degradation, purine metabolism, energy metabolism, degradation of fatty acid, amino acid metabolism, and focal adhesion. Moreover, we proposed multi-component panels of proteins and metabolites which could serve as a solid base to develop biomarkers for monitoring and predicting the efficacy of preoperative RT in rectal cancer patients.

Conclusion

We proved that an integrated multi-omic approach presents a valid look at the analysis of the global response to cancer treatment from the perspective of metabolomic reprogramming.

Prediction of T Stage of Rectal Cancer After Neoadjuvant Therapy by Multi-Parameter Magnetic Resonance Radiomics Based on Machine Learning Algorithms

INTRODUCTION

Since the response of patients with rectal cancer (RC) to neoadjuvant therapy is highly variable, there is an urgent need to develop accurate methods to predict the post-treatment T (pT) stage. The purpose of this study was to evaluate the utility of multi-parametric MRI radiomics models and identify the most accurate machine learning (ML) algorithms for predicting pT stage of RC.

METHOD

This retrospective study analyzed pretreatment clinical features of 171 RC patients who underwent 3 T MRI prior to neoadjuvant therapy and subsequent total mesorectal excision. Tumors were manually drawn as regions of interest (ROI) layer by layer on high-resolution T2-weighted image (T2WI) and contrast-enhanced T1-weighted image (CE-T1WI) using ITK-SNAP software. The most relevant features of pT stage from CE-T1WI, T2WI, and fusion features (combination of clinical features, CE-T1WI, and T2WI radiomics features) were extracted by the Least Absolute Shrinkage and Selection Operator method. Clinical, CE-T1WI radiomics, T2WI radiomics, and fusion models were established by ML multiple classifiers.

RESULTS

In the clinical model, the LightGBM algorithm demonstrated the highest efficiency, with AUC values of 0.857 and 0.702 for the training and test cohorts, respectively. For the T2WI and CE-T1WI models, the SVM algorithm was the most efficient; AUC = 0.969 and 0.868 in the training cohort, and 0.839 and 0.760 in the test cohort, respectively. The fusion model yielded the highest predictive performance using the LR algorithm; AUC = 0.967 and 0.932 in the training and test cohorts, respectively.

CONCLUSION

Radiomics features extracted from CE-T1WI and T2WI images and clinical features were effective predictors of pT stage in patients with rectal cancer who underwent neoadjuvant therapy. ML-based multi-parameter MRI radiomics model incorporating relevant clinical features can improve the pT stage prediction accuracy of RC.

Interpretation of Tumor Response Grade following Preoperative Therapy for Gastric Cancer: An Overview

Gastric cancer is among the top five causes of cancer-related death worldwide. Preoperative chemotherapy has been established as an option in patients with locally advanced gastric cancer. However, chemotherapy yields variable results, owing to the cellular and molecular heterogeneity of this disease. Identifying patients who did or did not respond to preoperative therapy can allow clinicians to alter treatment modalities and provide important information related to prognostication. A pathologic response to preoperative therapies, called the Tumor Response Grade (TRG), has been evaluated to quantify treatment response. Multiple systems for TRG have been established. However, the literature has demonstrated inconsistent results for TRG systems and prognosis, possibly due to variability in interpretation of tumor response between systems and interobserver variability. Radiographic responses to preoperative therapies using RECIST 1.1 criteria and endoscopically assessed tumor response have demonstrated association with survival; however, their use in gastric cancer remains challenging given the inability to accurately and consistently identify and measure the tumor, especially in the setting of neoadjuvant therapy, where treatment-related changes can obscure the gastric wall layers. While the response to preoperative therapies with positron emission tomography (PET) has shown promising results in esophageal and esophagogastric junction (EGJ) malignancies, its role in gastric cancer is still under investigation. This review is focused on summarizing the available literature related to evaluating TRG in gastric cancer, as well as providing a brief overview of the use of radiographic and endoscopic methods to assess response to preoperative therapies. Lastly, we outline future directions regarding the use of a universal TRG system to guide care and assist with prognosis.

Molecular Composition of Serum Exosomes Could Discriminate Rectal Cancer Patients with Different Responses to Neoadjuvant Radiotherapy

Identification of biomarkers that could be used for the prediction of the response to neoadjuvant radiotherapy (neo-RT) in locally advanced rectal cancer remains a challenge addressed by different experimental approaches. Exosomes and other classes of extracellular vesicles circulating in patients' blood represent a novel type of liquid biopsy and a source of cancer biomarkers. Here, we used a combined proteomic and metabolomic approach based on mass spectrometry techniques for studying the molecular components of exosomes isolated from the serum of rectal cancer patients with different responses to neo-RT. This allowed revealing several proteins and metabolites associated with common pathways relevant for the response of rectal cancer patients to neo-RT, including immune system response, complement activation cascade, platelet functions, metabolism of lipids, metabolism of glucose, and cancer-related signaling pathways. Moreover, the composition of serum-derived exosomes and a whole serum was analyzed in parallel to compare the biomarker potential of both specimens. Among proteins that the most properly discriminated good and poor responders were GPLD1 (AUC = 0.85, accuracy of 74%) identified in plasma as well as C8G (AUC = 0.91, accuracy 81%), SERPINF2 (AUC = 0.91, accuracy 79%) and CFHR3 (AUC = 0.90, accuracy 81%) identified in exosomes. We found that the proteome component of serum-derived exosomes has the highest capacity to discriminate samples of patients with different responses to neo-RT when compared to the whole plasma proteome and metabolome. We concluded that the molecular components of exosomes are associated with the response of rectal cancer patients to neo-RT and could be used for the prediction of such response.

Rectal cancer response to neoadjuvant chemoradiotherapy evaluated with MRI: Development and validation of a classification algorithm

OBJECTIVE

The aim of this study was to develop and validate a decision support model using data mining algorithms, based on morphologic features derived from MRI images, to discriminate between complete responders (CR) and non-complete responders (NCR) patients after neoadjuvant chemoradiotherapy (CRT), in a population of patients with locally advanced rectal cancer (LARC).

METHODS

Two populations were retrospectively enrolled: group A (65 patients) was used to train a data mining decision tree algorithm whereas group B (30 patients) was used to validate it. All patients underwent surgery; according to the histology evaluation, patients were divided in CR and NCR. Staging and restaging MRI examinations were retrospectively analysed and seven parameters were considered for data mining classification. Five different classification methods were tested and evaluated in terms of sensitivity, specificity, accuracy and AUC in order to identify the classification model able to achieve the best performance. The best classification algorithm was subsequently applied to group B for validation: sensitivity, specificity, positive and negative predictive value, accuracy and ROC curve were calculated. Inter and intra-reader agreement were calculated.

RESULTS

Four features were selected for the development of the classification algorithm: MRI tumor regression grade (MR-TRG), staging volume (SV), tumor volume reduction rate (TVRR) and signal intensity reduction rate (SIRR). The decision tree J48 showed the highest efficiency: when applied to group B, all the CR and 18/21 NCR were correctly classified (sensitivity 85.71%, specificity 100%, PPV 100%, NPV 94.2%, accuracy 95.7%, AUC 0.833). Both inter- and intra-reader evaluation showed good agreement (κ > 0.6).

CONCLUSIONS

The proposed decision support model may help in distinguishing between CR and NCR patients with LARC after CRT.

Radiomics signature as a new biomarker for preoperative prediction of neoadjuvant chemoradiotherapy response in locally advanced rectal cancer

PURPOSE

Whether radiomics methods are useful in prediction of therapeutic response to neoadjuvant chemoradiotherapy (nCRT) is unclear. This study aimed to investigate multiple magnetic resonance imaging (MRI) sequence-based radiomics methods in evaluating therapeutic response to nCRT in patients with locally advanced rectal cancer (LARC).

METHODS

This retrospective study enrolled patients with LARC (06/2014-08/2017) and divided them into nCRT-sensitive and nCRT-resistant groups according to postoperative tumor regression grading results. Radiomics features from preoperative MRI were extracted, followed by dimension reduction using the minimum redundancy maximum relevance filter. Three machine-learning classifiers and an ensemble classifier were used for therapeutic response prediction. Radiomics nomogram incorporating clinical parameters were constructed using logistic regression. The receiver operating characteristic (ROC), decision curves analysis (DCA) and calibration curves were also plotted to evaluate the prediction performance.

RESULTS

The machine learning classifiers showed good prediction performance for therapeutic responses in LARC patients (n=189). The ROC curve showed satisfying performance (area under the curve [AUC], 0.830; specificity, 0.794; sensitivity, 0.815) in the validation group. The radiomics signature included 30 imaging features derived from axial T1-weighted imaging with contrast and sagittal T2-weighted imaging and exhibited good predictive power for nCRT. A radiomics nomogram integrating carcinoembryonic antigen levels and tumor diameter showed excellent performance with an AUC of 0.949 (95% confidence interval, 0.892-0.997; specificity, 0.909; sensitivity, 0.879) in the validation group. DCA confirmed the clinical usefulness of the nomogram model.

CONCLUSION

The radiomics method using multiple MRI sequences can be used to achieve individualized prediction of nCRT in patients with LARC before treatment.

Value of volumetric and textural analysis in predicting the treatment response in patients with locally advanced rectal cancer

OBJECTIVE

The aim of this study was to assess the value of baseline 18F-FDG PET/CT in predicting the response to neoadjuvant chemo-radiotherapy (NCRT) in patients with locally advanced rectal cancer (LARC) via the volumetric and texture data obtained from 18F-FDG PET/CT images.

METHODS

 In total, 110 patients who had undergone NCRT after initial PET/CT and followed by surgical resection were included in this study. Patients were divided into two groups randomly as a train set (n: 88) and test set (n: 22). Pathological response using three-point tumor regression grade (TRG) and metastatic lymph nodes in PET/CT images were determined. TRG1 were accepted as responders and TRG2-3 as non-responders. Region of interest for the primary tumors was drawn and volumetric features (metabolic tumor volume (MTV) and total lesion glycolysis (TLG)) and texture features were calculated. In train set, the relationship between these features and TRG was investigated with Mann-Whitney U test. Receiver operating curve analysis was performed for features with p < 0.05. Correlation between features were evaluated with Spearman correlation test, features with correlation coefficient < 0.8 were evaluated with the logistic regression analysis for creating a model. The model obtained was tested with a test set that has not been used in modeling before.

RESULTS

 In train set 32 (36.4%) patients were responders. The rate of visually detected metastatic lymph node at baseline PET/CT was higher in non-responders than responders (71.4% and 46.9%, respectively, p = 0.022). There was a statistically significant difference between TLG, MTV, SHAPE_compacity, NGLDMcoarseness, GLRLM_GLNU, GLRLM_RLNU, GLZLM_LZHGE and GLZLM_GLNU between responders and non-responders. MTV and NGLDMcoarseness demonstrated the most significance (p = 0.011). A multivariate logistic regression analysis that included MTV, coarseness, GLZLM_LZHGE and lymph node metastasis was performed. Multivariate analysis demonstrated MTV and lymph node metastasis were the most meaningful parameters. The model's AUC was calculated as 0.714 (p = 0.001,0.606-0.822, 95% CI). In test set, AUC was determined 0.838 (p = 0.008,0.671-1.000, 95% CI) in discriminating non-responders.

CONCLUSIONS

Although there were points where textural features were found to be significant, multivariate analysis revealed no diagnostic superiority over MTV in predicting treatment response. In this study, it was thought higher MTV value and metastatic lymph nodes in PET/CT images could be a predictor of low treatment response in patients with LARC.

Preoperative Fibrinogen-Albumin Ratio Index (FARI) is a Reliable Prognosis and Chemoradiotherapy Sensitivity Predictor in Locally Advanced Rectal Cancer Patients Undergoing Radical Surgery Following Neoadjuvant Chemoradiotherapy

Background

Inflammatory response and nutritional status are associated with cancer development and progression. The purpose of this study was to explore whether the preoperative fibrinogen-albumin ratio index (FARI) is related to prognosis and chemoradiotherapy outcome of radical surgery after neoadjuvant chemoradiotherapy (NCRT) in patients with locally advanced rectal cancer (LARC).

Methods

In total, 123 patients with LARC who underwent radical surgery after NCRT between June 2012 and December 2018 were collected in this study. Time-dependent receiver operating characteristic (ROC) curve analysis was made to evaluate the ability of the markers for forecasting prognosis. The correlation between FARI and clinicopathological parameters was analyzed. The Kaplan-Meier survival analysis, univariate and multivariate analysis based on Cox proportional hazards models, and subgroup analysis were performed to evaluate overall survival (OS) and disease-free survival (DFS). A nomogram was constructed to evaluate the predictive role of FARI in DFS.

Results

The ROC curve analysis showed that the ability of FARI on DFS prediction was superior to those of other inflammatory markers and carcinoembryonic antigen (CEA) (P<0.05). Based on the Youden's index, the optimal cut-off value of FARI was 8.8%. High FARI patients (>8.8%) showed a poor response to NCRT and a decreased DFS rate (P<0.05). In addition, multivariate analysis revealed that FARI (HR=3.098, P=0.033), neutrophil-to-lymphocyte ratio (NLR), and postoperative T stage were independent prognostic factors for DFS in TNM stage III LARC patients. However, FARI failed to distinguish patients with poor OS. Harrell's concordance index (C-index) of the nomogram containing FARI (0.807) was obviously higher than that without it (0.732) among LARC patients who underwent radical surgery after NCRT. Moreover, multivariate analysis revealed FARI (OR=3.044, P=0.012) as an independent predictor for response to NCRT.

Conclusion

Among LARC patients who underwent radical surgery after NCRT, preoperative FARI is an independent prognostic factor for DFS and an independent predictor for response to NCRT.

Impact of preoperative chemotherapy on the histological response of patients with peritoneal metastases from colorectal cancer according to peritoneal regression grading score (PRGS) and TRG

BACKGROUND

This study evaluated the histologic response after preoperative systemic therapy (pST) using the Peritoneal Regression Grading Score (PRGS) and tumor regression grade (TRG) classifications for patients with peritoneal metastases (PM) from colorectal cancer (CRC).

METHODS

Twenty-three patients were selected from a prospective database of 196 patients who underwent CRS followed by HIPEC for synchronous PM from CRC. In all study patients, biopsies of the PM obtained before pST (during the first laparoscopy) and after pST (during cytoreductive surgery) were compared.

RESULTS

Complete (PRGS 1), Major (PRGS 2), Minor (PRGS 3) and no histological responses (PRGS 4) were obtained in 17,5%, 52% and 13% and 17,5% of patients, respectively. Major (TRG 1-2), partial (TRG3), and no (TRG4-5) histological tumor regression were observed in 61%, 9% and 30% of patients, respectively. Regardless of the classification applied, median OS was significantly higher in patients with a "complete or major" response than in those with a "minor/partial or no" response (54 vs. 26 months, p < 0.05).

CONCLUSIONS

The PRGS and TRG can be used in clinical practice to evaluate the histological response after pST. This study demonstrated that a complete histologic response of PM from CRC can be obtained after pST.

Improved Outcomes for Responders After Treatment with Induction Chemotherapy and Chemo(re)irradiation for Locally Recurrent Rectal Cancer

BACKGROUND

Despite improvements in the multimodality treatment for patients with locally recurrent rectal cancer (LRRC), oncological outcomes remain poor. This study evaluated the effect of induction chemotherapy and subsequent chemo(re)irradiation on the pathologic response and the rate of resections with clear margins (R0 resection) in relation to long-term oncological outcomes.

METHODS

All consecutive patients with LRRC treated in the Catharina Hospital Eindhoven who underwent a resection after treatment with induction chemotherapy and subsequent chemo(re)irradiation between January 2010 and December 2018 were retrospectively reviewed. Induction chemotherapy consisted of CAPOX/FOLFOX. Endpoints were pathologic response, resection margin and overall survival (OS), disease free survival (DFS), local recurrence free survival (LRFS), and metastasis free survival (MFS).

RESULTS

A pathologic complete response was observed in 22 patients (17%), a "good" response (Mandard 2-3) in 74 patients (56%), and a "poor" response (Mandard 4-5) in 36 patients (27%). An R0 resection was obtained in 83 patients (63%). The degree of pathologic response was linearly correlated with the R0 resection rate (p = 0.026). In patients without synchronous metastases, pathologic response was an independent predictor for LRFS, MFS, and DFS (p = 0.004, p = 0.003, and p = 0.024, respectively), whereas R0 resection was an independent predictor for LRFS and OS (p = 0.020 and p = 0.028, respectively).

CONCLUSIONS

Induction chemotherapy in addition to neoadjuvant chemo(re)irradiation is a promising treatment strategy for patients with LRRC with high pathologic response rates that translate into improved oncological outcomes, especially when an R0 resection has been achieved.

Evaluation of a new histological grading system for assessing the response to chemotherapy of peritoneal metastases from colorectal cancer: A mouse model study

This experimental study evaluated the histological response of peritoneal metastases (PM) from colorectal cancer (CRC) after preoperative systemic chemotherapy (pCT). The results demonstrated that the Peritoneal Regression Grade Score could be used in medical practice.

AIM

The aim was to evaluate the histological criteria used by the tumour regression grade (TRG) and Peritoneal Regression Grade Score (PRGS) for determining the response to chemotherapy (CT), in a mouse model of peritoneal metastases (PM) from colorectal cancer (CRC).

METHODS

Twenty immunocompetent BALB/c mice were randomized into four groups at day (D) 10 after intraperitoneal (ip) injection with bioluminescent CRC tumour cells (CT26-luc). A histology before treatment group was obtained by sacrifice on D10; the other groups all received one of the following ip treatments over 15 days: 5% glucose (control, G5); 5-fluorouracil (5FU, 0.03 mg/g); or 5FU with oxaliplatin (Ox, 0.006 mg/g). The histological response (HR) was analysed by comparing the histology of PM before and after treatment, using both scores: TRG and PRGS.

RESULTS

All mice showed limited PM as visualised by bioluminescence and confirmed at the time of sacrifice in the histology before treatment group. The mean peritoneal carcinomatosis index (PCI) was = 8 [6-10], The rate of complete HR was significantly higher in the Ox-5FU group (83.3%) than 5FU group (0%) and G5 group (0%) (p = 0.016). Fibrosis was present only in CT-treated groups (p = 0.05). PCI, ascites volume and haemorrhagic ascites were significantly higher in the G5 group than CT groups (p < 0.05).

CONCLUSIONS

The TRG score can be used in practice when we want to compare the HR between the primary tumour and the PMs. The PRGS is a good measure of HR and is correlated with the efficacy of CT.

Area of residual tumor (ART) can predict prognosis after post neoadjuvant therapy resection for pancreatic ductal adenocarcinoma

An increasing number of patients with pancreatic ductal adenocarcinoma (PDAC) have undergone resection after neoadjuvant therapy (NAT). We have reported Area of Residual Tumor (ART) as a useful pathological assessment method to predict patient outcomes after post NAT resection in various cancer types. The aim of this study was to assess the prognostic performance of ART in PDAC resected after NAT. Sixty-three patients with PDAC after post NAT resection were analyzed. The viable residual tumor area was outlined and the measurement of ART was performed using morphometric software. The results were compared with those of the College of American Pathologist (CAP) regression grading. Of 63 cases, 39 (62%) patients received chemoradiation therapy and 24 (38%) received chemotherapy only. The median value of ART was 163 mm2. Large ART with 220 mm2 as the cut-off was significantly associated with lymphatic invasion, vascular invasion and perineural invasion, while CAP regression grading was not associated with any clinicopathological features. By multivariate analysis, large ART (≥220 mm2) was an independent predictor of shorter relapse free survival. Together with our previous reports, an ART-based pathological assessment may become a useful method to predict patient outcomes after post NAT resection across various cancer types.

Identification of protein clusters predictive of tumor response in rectal cancer patients receiving neoadjuvant chemo-radiotherapy

Preoperative neoadjuvant chemoradiotherapy (nCRT) is the gold standard in locally advanced rectal cancer, only 10–30% of patients achieving benefits. Currently, there is a need of a reliable selection of markers for the identification of poor or non-responders prior to therapy. In this work, we compared protein profiles before therapy of patients differing in their responses to nCRT to find novel predictive markers of response to therapy. Patients were grouped into 3 groups according to their tumor regression grading (TRG) after surgery: 'TRG 1–2′, good responders, 'TRG 3′ and 'TRG 4′, poor responders. Paired surgical specimens of rectal cancer and healthy (histologically confirmed) rectal tissues from 15 patients were analysed before nCRT by two dimensional difference in gel electrophoresis followed by mass spectrometry. Thirty spots were found as differentially expressed (p < 0.05). Among them, 3 spots (spots 471, 683 and 684) showed an increased amount of protein in poor responders compared with good responders, and they were more tumor associated compared with healthy tissues. Proteins of these spots were identified as fibrinogen ß chain fragment D, actin isoforms, B9 and B5 serpins, cathepsin D isoforms and peroxiredoxin-4. In an independent validation set of 20 rectal carcinomas we validated the increased fibrinogen ß chain abundance before nCRT in poor responders by immunoblotting. In conclusion, we propose a risk-stratification tool in predicting the response to nCRT treatment in rectal cancer based on the quantity of these proteins.

Assessment of risk factors affecting mortality in patients with colorectal cancer

INTRODUCTION

The most important risk factors for colorectal cancer are age, high ASA score, anemia, low albumin, tumor stage, histopathological properties, tumor's relationship with adjacent tissues, positivity of surgical borders and timing of the surgical procedure.

AIM

To determine possible risk factors for mortality in patients undergoing colorectal cancer surgery.

MATERIAL AND METHODS

The medical records of 101 consecutive patients who underwent colorectal cancer surgery at the Department of Surgery, Sutcu Imam University Faculty of Medicine, Kahramanmaras, Turkey between January 2008 and November 2015 were retrospectively reviewed. The patients were divided into two groups: surviving (n = 76) and deceased (n = 25) groups. The groups were compared in terms of several demographic, clinical, biochemical, and histopathological parameters. In addition, risk factors for mortality were analyzed with multivariate analysis. SPSS 22.2, PAST 3, and MedCalc 14 software packages were used for statistical analyses.

RESULTS

The surviving and deceased groups significantly differed with respect to age (p = 0.001), hemoglobin (p = 0.001), lymph node positivity (p = 0.009), positive lymph node/total lymph node ratio (p = 0.012), thrombocyte count (p = 0.047), lymphovascular invasion (p = 0.028), urgency of admission (emergency/elective) (p = 0.036), and postoperative carcinoembryonic antigen (CEA) level (p = 0.002). A receiver operating characteristics curve was drawn to determine the cut-off values of various parameters including age (63), hemoglobin (12.8), node positivity (3), positive/total lymph node ratio (0.435) and thrombocyte count (308), with age (p < 0.001), hemoglobin (p < 0.001), node positivity (p = 0.025) and positive/total lymph node ratio (p = 0.024) being significantly different. A multivariate analysis revealed that age (p = 0.049), hemoglobin (p = 0.045), and positive/total lymph node ratio (p = 0.025) were independent risk factors for mortality.

CONCLUSIONS

This study shows that older age, lower hemoglobin level, and high positive/total lymph node ratio were independent risk factors for mortality among colorectal cancer patients.

Assessment of risk factors affecting mortality in patients with colorectal cancer

INTRODUCTION

The most important risk factors for colorectal cancer are age, high ASA score, anemia, low albumin, tumor stage, histopathological properties, tumor's relationship with adjacent tissues, positivity of surgical borders and timing of the surgical procedure.

AIM

To determine possible risk factors for mortality in patients undergoing colorectal cancer surgery.

MATERIAL AND METHODS

The medical records of 101 consecutive patients who underwent colorectal cancer surgery at the Department of Surgery, Sutcu Imam University Faculty of Medicine, Kahramanmaras, Turkey between January 2008 and November 2015 were retrospectively reviewed. The patients were divided into two groups: surviving (n = 76) and deceased (n = 25) groups. The groups were compared in terms of several demographic, clinical, biochemical, and histopathological parameters. In addition, risk factors for mortality were analyzed with multivariate analysis. SPSS 22.2, PAST 3, and MedCalc 14 software packages were used for statistical analyses.

RESULTS

The surviving and deceased groups significantly differed with respect to age (p = 0.001), hemoglobin (p = 0.001), lymph node positivity (p = 0.009), positive lymph node/total lymph node ratio (p = 0.012), thrombocyte count (p = 0.047), lymphovascular invasion (p = 0.028), urgency of admission (emergency/elective) (p = 0.036), and postoperative carcinoembryonic antigen (CEA) level (p = 0.002). A receiver operating characteristics curve was drawn to determine the cut-off values of various parameters including age (63), hemoglobin (12.8), node positivity (3), positive/total lymph node ratio (0.435) and thrombocyte count (308), with age (p < 0.001), hemoglobin (p < 0.001), node positivity (p = 0.025) and positive/total lymph node ratio (p = 0.024) being significantly different. A multivariate analysis revealed that age (p = 0.049), hemoglobin (p = 0.045), and positive/total lymph node ratio (p = 0.025) were independent risk factors for mortality.

CONCLUSIONS

This study shows that older age, lower hemoglobin level, and high positive/total lymph node ratio were independent risk factors for mortality among colorectal cancer patients.

Neutrophil to Lymphocyte Ratio (NLR) and Derived Neutrophil to Lymphocyte Ratio (d-NLR) Predict Non-Responders and Postoperative Complications in Patients Undergoing Radical Surgery After Neo-Adjuvant Radio-Chemotherapy for Rectal Adenocarcinoma

In order to evaluate neutrophil-to-lymphocyte ratio (NLR) and derived neutrophil-to-lymphocyte ratio (d-NLR) in predicting response and complications in rectal cancer patients who underwent surgery after neo-adjuvant radio-chemotherapy, 87 patients were evaluated. Cutoffs before and after radio-chemotherapy were respectively 2.8 and 3.8 for NLR, and 1.4 and 2.3 for d-NLR. They were analyzed in relation to clinical and pathological outcomes. Patients with preoperative NLR and d-NLR higher than cutoffs had significantly higher rates of tumor regression grade response (TRG ≥ 4) and postoperative complications. Elevated NLR and d-NLR after radio-chemotherapy are associated with worse pathological and clinical outcome.

Histopathologic tumor response after induction chemotherapy and stereotactic body radiation therapy for borderline resectable pancreatic cancer

BACKGROUND

While clinical outcomes following induction chemotherapy and stereotactic body radiation therapy (SBRT) have been reported for borderline resectable pancreatic cancer (BRPC) patients, pathologic response has not previously been described.

METHODS

This single-institution retrospective review evaluated BRPC patients who completed induction gemcitabine-based chemotherapy followed by SBRT and surgical resection. Each surgical specimen was assigned two tumor regression grades (TRG), one using the College of American Pathologists (CAP) criteria and one using the MD Anderson Cancer Center (MDACC) criteria. Overall survival (OS) and progression free survival (PFS) were correlated to TRG score.

RESULTS

We evaluated 36 patients with a median follow-up of 13.8 months (range, 6.1-24.8 months). The most common induction chemotherapy regimen (82%) was GTX (gemcitabine, docetaxel, capecitabine). A median SBRT dose of 35 Gy (range, 30-40 Gy) in 5 fractions was delivered to the region of vascular involvement. The margin-negative resection rate was 97.2%. Improved response according to MDACC grade trended towards superior PFS (P=061), but not OS. Any neoadjuvant treatment effect according to MDACC scoring (IIa-IV vs. I) was associated with improved OS and PFS (both P=0.019). We found no relationship between CAP score and OS or PFS.

CONCLUSIONS

These data suggest that the increased pathologic response after induction chemotherapy and SBRT is correlated with improved survival for BRPC patients.