18F-FDG PET/CT has a high impact on patient management and provides powerful prognostic stratification in the primary staging of esophageal cancer: a prospective study with mature survival data

Advances in the Imaging of Esophageal and Gastroesophageal Junction Malignancies

Accurate imaging is key for the diagnosis and treatment of esophageal and gastroesophageal junction cancers . Current imaging modalities, such as computed tomography (CT) and 18F-FDG (2-deoxy-2-[18F]fluoro-D-glucose) positron emission tomography (PET)/CT, have limitations in accurately staging these cancers. MRI shows promise for T staging and residual disease assessment. Novel PET tracers, like FAPI, FLT, and hypoxia markers, offer potential improvements in diagnostic accuracy. 18F-FDG PET/MRI combines metabolic and anatomic information, enhancing disease evaluation. Radiomics and artificial intelligence hold promise for early detection, treatment planning, and response assessment. Theranostic nanoparticles and personalized medicine approaches offer new avenues for cancer therapy.

Esophageal cancer - French intergroup clinical practice guidelines for diagnosis, treatments and follow-up (TNCD, SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, ACHBT, SFP, RENAPE, SNFCP, AFEF, SFR)

INTRODUCTION

This document is a summary of the French intergroup guidelines regarding the management of esophageal cancer (EC) published in July 2022, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org).

METHODS

This collaborative work was conducted under the auspices of several French medical and surgical societies involved in the management of EC. Recommendations were graded in three categories (A, B and C), according to the level of evidence found in the literature until April 2022.

RESULTS

EC diagnosis and staging evaluation are mainly based on patient's general condition assessment, endoscopy plus biopsies, TAP CT-scan and 18F FDG-PET. Surgery alone is recommended for early-stage EC, while locally advanced disease (N+ and/or T3-4) is treated with perioperative chemotherapy (FLOT) or preoperative chemoradiation (CROSS regimen) followed by immunotherapy for adenocarcinoma. Preoperative chemoradiation (CROSS regimen) followed by immunotherapy or definitive chemoradiation with the possibility of organ preservation are the two options for squamous cell carcinoma. Salvage surgery is recommended for incomplete response or recurrence after definitive chemoradiation and should be performed in an expert center. Treatment for metastatic disease is based on systemic therapy including chemotherapy, immunotherapy or combined targeted therapy according to biomarkers testing such as HER2 status, MMR status and PD-L1 expression.

CONCLUSION

These guidelines are intended to provide a personalised therapeutic strategy for daily clinical practice and are subject to ongoing optimization. Each individual case should be discussed by a multidisciplinary team.

Preoperative prediction of clinical and pathological stages for patients with esophageal cancer using PET/CT radiomics

BACKGROUND

Preoperative stratification is critical for the management of patients with esophageal cancer (EC). To investigate the feasibility and accuracy of PET-CT-based radiomics in preoperative prediction of clinical and pathological stages for patients with EC.

METHODS

Histologically confirmed 100 EC patients with preoperative PET-CT images were enrolled retrospectively and randomly divided into training and validation cohorts at a ratio of 7:3. The maximum relevance minimum redundancy (mRMR) was applied to select optimal radiomics features from PET, CT, and fused PET-CT images, respectively. Logistic regression (LR) was applied to classify the T stage (T1,2 vs. T3,4), lymph node metastasis (LNM) (LNM(-) vs. LNM(+)), and pathological state (pstage) (I-II vs. III-IV) with features from CT (CT_LR_Score), PET (PET_LR_Score), fused PET/CT (Fused_LR_Score), and combined CT and PET features (CT + PET_LR_Score), respectively.

RESULTS

Seven, 10, and 7 CT features; 7, 8, and 7 PET features; and 3, 6, and 3 fused PET/CT features were selected using mRMR for the prediction of T stage, LNM, and pstage, respectively. The area under curves (AUCs) for T stage, LNM, and pstage prediction in the validation cohorts were 0.846, 0.756, 0.665, and 0.815; 0.769, 0.760, 0.665, and 0.824; and 0.727, 0.785, 0.689, and 0.837 for models of CT_LR_Score, PET_ LR_Score, Fused_ LR_Score, and CT + PET_ LR_Score, respectively.

CONCLUSIONS

Accurate prediction ability was observed with combined PET and CT radiomics in the prediction of T stage, LNM, and pstage for EC patients.

CRITICAL RELEVANCE STATEMENT

PET/CT radiomics is feasible and promising to stratify stages for esophageal cancer preoperatively.

KEY POINTS

• PET-CT radiomics achieved the best performance for Node and pathological stage prediction. • CT radiomics achieved the best AUC for T stage prediction. • PET-CT radiomics is feasible and promising to stratify stages for EC preoperatively.

Impact of Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography in the Management of Oligometastatic Renal Cell Carcinoma

Background

Prostate-specific membrane antigen (PSMA) is overexpressed in the neovasculature of renal cell carcinoma (RCC). However, there remains limited evidence regarding the use of PSMA positron emission tomography/computed tomography (PET/CT) in RCC.

Objective

To assess the impact of PSMA PET/CT in the management of metastatic RCC.

Design, setting, and participants

This was a retrospective review of patients who underwent PSMA PET/CT from 2014 to 2020 for restaging or suspected metastatic RCC in a tertiary academic setting.

Outcome measurements and statistical analysis

Management plans before and after PSMA PET/CT were recorded. Impact was classified as high (change of treatment intent, modality, or site), medium (change in treatment method), or low. Secondary outcomes included the patient-level detection rate, PSMA PET/CT parameters, sensitivity, and comparison to CT and, if available, fluorodeoxyglucose (FDG) PET/CT.

Results and limitations

Sixty-one patients met the inclusion criteria, of whom 54 (89%) had clear cell RCC. PSMA-positive disease was detected in 51 patients (84%). For 30 patients (49%) there was a change in management due to PSMA PET/CT (high impact, 29 patients, 48%). In 15 patients (25%), more metastases were detected on PSMA PET/CT than on CT. The sensitivity of combined PSMA PET/CT and diagnostic CT was 91% (95% confidence interval 77–98%). In a subcohort of 40 patients, the detection rate was 88% for PSMA and 75% for FDG PET/CT (p = 0.17). The maximum standardised uptake value (SUV_max) was higher for PSMA than for FDG PET/CT (15.2 vs 8.0; p = 0.02). Limitations include selection bias due to the retrospective design, and a lack of corresponding histopathology for all patients.

Conclusions

PSMA PET/CT is a promising imaging modality in metastatic RCC and led to a change in management in 49% of patients. PSMA PET/CT detected additional metastases compared to CT in 25% of patients and registered a significantly higher SUV_max than FDG PET/CT. Prospective studies are required to further define its role.

Patient summary

We report on a group of patients undergoing a new type of imaging for suspected advanced kidney cancer, called PSMA PET/CT. This imaging changed the management plan in 49% of the patients. PSMA PET/CT detected metastases in 84% of our patients and detected more metastases than computed tomography imaging in 25%.

Can 18F-FDG PET/CT Radiomics Features Predict Clinical Outcomes in Patients with Locally Advanced Esophageal Squamous Cell Carcinoma?

Simple Summary

PET/CT is an important staging modality in the baseline assessment of locally advanced esophageal squamous cell carcinoma. Accurate staging and response prediction in these patients is essential for management. The aim of this retrospective study was to assess the usefulness of ¹⁸F-FDG PET/CT radiomics features in predicting outcomes such as tumor and nodal categories, PET-based response to induction chemotherapy, progression-free survival, and overall survival. In a final cohort of 74 patients, we found that the developed radiomics models can predict these clinical and prognostic outcomes with reasonable accuracy, similar or better than those derived from conventional imaging. Future studies with a larger cohort would be helpful in establishing the significance of these models.

Abstract

This study aimed to assess the usefulness of radiomics features of ¹⁸F-FDG PET/CT in patients with locally advanced esophageal cancers (ESCC) in predicting outcomes such as clinical tumor (cT) and nodal (cN) categories, PET response to induction chemotherapy (PET response), progression-free survival (PFS), and overall survival (OS). Pretreatment PET/CT images from patients who underwent concurrent chemoradiotherapy from July 2002 to February 2017 were segmented, and data were split into training and test sets. Model development was performed on the training datasets and a maximum of five features were selected. Final diagnostic accuracies were determined using the test dataset. A total of 86 PET/CTs (58 men and 28 women, mean age 65 years) were segmented. Due to small lesion size, 12 patients were excluded. The diagnostic accuracies as derived from the CT, PET, and combined PET/CT test datasets were as follows: cT category—70.4%, 70.4%, and 81.5%, respectively; cN category—69.0%, 86.2%, and 86.2%, respectively; PET response—60.0%, 66.7%, and 70.0%, respectively; PFS—60.7%, 75.0%, and 75.0%, respectively; and OS—51.7%, 55.2%, and 62.1%, respectively. A radiomics assessment of locally advanced ESCC has the potential to predict various clinical outcomes. External validation of these models would be further helpful.

Can 18F-FDG PET/CT Radiomics Features Predict Clinical Outcomes in Patients with Locally Advanced Esophageal Squamous Cell Carcinoma?

This study aimed to assess the usefulness of radiomics features of ¹⁸F-FDG PET/CT in patients with locally advanced esophageal cancers (ESCC) in predicting outcomes such as clinical tumor (cT) and nodal (cN) categories, PET response to induction chemotherapy (PET response), progression-free survival (PFS), and overall survival (OS). Pretreatment PET/CT images from patients who underwent concurrent chemoradiotherapy from July 2002 to February 2017 were segmented, and data were split into training and test sets. Model development was performed on the training datasets and a maximum of five features were selected. Final diagnostic accuracies were determined using the test dataset. A total of 86 PET/CTs (58 men and 28 women, mean age 65 years) were segmented. Due to small lesion size, 12 patients were excluded. The diagnostic accuracies as derived from the CT, PET, and combined PET/CT test datasets were as follows: cT category-70.4%, 70.4%, and 81.5%, respectively; cN category-69.0%, 86.2%, and 86.2%, respectively; PET response-60.0%, 66.7%, and 70.0%, respectively; PFS-60.7%, 75.0%, and 75.0%, respectively; and OS-51.7%, 55.2%, and 62.1%, respectively. A radiomics assessment of locally advanced ESCC has the potential to predict various clinical outcomes. External validation of these models would be further helpful.

18F-FDG PET/CT as predictive and prognostic factor in esophageal cancer treated with combined modality treatment

Purpose

[18F] fluorodeoxyglucose positron emission tomography/computed tomography ([18F] FDG-PET/CT) is used for diagnosis, staging, response assessment and prognosis prediction in different tumors, but its role in esophageal cancer is still debated. The aim of this study was to evaluate the role of semiquantitative baseline PET parameters as possible prognostic and predictive factors in a series of esophageal carcinomas treated with combined modalities.

Methods

43 patients with esophageal carcinoma were treated with chemoradiotherapy (CRT) followed by surgery in 20 cases and underwent pre-treatment 18F-FDG-PET/CT. Semiquantitative PET parameters were evaluated including Standardized Uptake Value (SUVmax e SUVmean), Metabolic Tumor Volume (MTV) and Total Lesion Glycolysis (TLG) with isocontour of 41 and 50%. Further variables analyzed were gender, primary tumor site, histological type, use of surgery, achievement of a radical resection and the type of chemotherapy regimen. The correlation of all variables with treatment response, loco-regional control (LR), Overall survival (OS) and Disease-Free Survival (DFS) was evaluated.

Results

SUVmax, SUVmean50 and SUVmean41 were significantly higher in node-positive cases and in squamous cell carcinomas. With respect to prognostic factors, MTV was found to be correlated with OS: patients with MTV41 < 11.32 cm³ and MTV50 < 8.07 cm³ (both p values = 0.04) showed better 3-year OS rates (33 vs. 20%). Further factors predicting a better prognosis were the use of surgery and radical resection (R0) (both p values < 0.01).

Conclusions

Pre-treatment MTV values were significant prognostic factors for OS, together with the use of surgery and R0 resection in esophageal cancers treated with multimodal therapies.

Influence of sarcopenia, clinical data, and 2-[18F] FDG PET/CT in outcome prediction of patients with early-stage adenocarcinoma esophageal cancer

PURPOSE

To determine the prognostic value of sarcopenia measurements done on staging 2-[18F] FDG PET/CT together with metabolic activity of the tumor in patients with adenocarcinoma esophagogastric cancer with surgical treatment.

METHODS

Patients with early-stage, surgically treated esophageal adenocarcinoma and available pre-treatment 2-[18F] FDG PET/CT were included. The standard uptake value (SUV) and SUV normalized by lean body mass (SUL) were recorded. Skeletal muscle index (SMI) was measured at the L3 level on the CT component of the PET/CT. Sarcopenia was defined as SMI < 34.4cm²/m² in women and < 45.4cm²/m² in men.

RESULTS

Of the included 145 patients. 30% were sarcopenic at baseline. On the univariable Cox proportional hazards analysis, ECOG, surgical T and N staging, lymphovascular invasion (LVI) positive lymph nodes, and sarcopenia were significant prognostic factors concerning RFS and OS. On multivariable Cox regression analysis, surgical N staging (p = 0.025) and sarcopenia (p = 0.022) remained significant poor prognostic factors for OS and RFS. Combining the clinical parameters with the imaging-derived nutritional evaluation of the patient but not metabolic parameters of the tumor showed improved predictive ability for OS and RFS.

CONCLUSION

Combining the patients' imaging-derived sarcopenic status with standard clinical data, but not metabolic parameters, offered an overall improved prognostic value concerning OS and RFS.

Prognostic Significance of Pretreatment Staging With 18F-FDG PET in Esophageal Cancer: A Nationwide Population-Based Study

PURPOSE OF THE REPORT

Without the routine use of 18F-FDG PET for initial staging of esophageal cancer, it may lead to inaccurate staging and suboptimal treatment. The purpose of this study was to evaluate the prognostic significance of pretreatment 18F-FDG PET in nonmetastatic esophageal cancer by comparing the survival between patients with and without pretreatment PET.

MATERIALS AND METHODS

We selected newly diagnosed esophageal cancer patients without metastasis between 2009 and 2015 from Taiwan Cancer Registry and National Health Insurance Research Database. Pretreatment 18F-FDG PET staging was determined according to the implementation of PET within 90 days before starting treatment. Overall survival was calculated from the day of treatment initiation to the death from any cause. Survival curves were compared between patients with and without PET staging using the log-rank test.

RESULTS

Of the 9078 patients included, 1765 (19.4%) and 7313 (80.6%) patients were staged with and without pretreatment PET, respectively. The median follow-up time for all patients and survivors was 1.29 years and 5.46 years, respectively. The pretreatment PET group had a lower risk of death than the no pretreatment PET group (hazards ratio, 0.74; 95% confidence interval, 0.70-0.79; P < 0.001). After adjusting for age, stage, histology, and tumor location, pretreatment PET remained significantly correlated with a lower risk of death (hazards ratio, 0.78; 95% confidence interval, 0.73-0.83; P < 0.001).

CONCLUSIONS

The utilization of pretreatment 18F-FDG PET for staging in nonmetastatic esophageal malignancy is associated with a lower risk of death even after adjusting for age, stage, histology, and tumor location.

Clinical relevance of incidental focal breast uptake on fluorine-18 fluorodeoxyglucose PET/computed tomography studies: an experience in a high-load center of Spain

AIM

We aimed to determine the frequency and clinical significance of breast incidental uptake (BIU) detected through fluorine-18 fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) in a single, high-load center.

PATIENTS AND METHODS

In this retrospective study, we analyzed a total of 13 763 PET/CT studies performed from January 2017 to January 2020. After excluding 3148 scans, the maximum standardized uptake value (SUVmax) and maximum diameter (cm) of each BIU were measured. Clinical management, ultrasound/mammography and pathology reports were analyzed.

RESULTS

We found BIU in 27 scans of 26 patients (0.3% of the studies). Mean age was 62.2 years and 88.5% were women; 84.6% underwent PET/CT for oncological indications. Ultrasound/mammography was consequently performed in 23 patients (88.5%), and histological correlations were available for Breast Imaging Reporting and Data System categories 4 and 5. Finally, lesions were benign in 14 patients (60.9%; two of them with low/intermediate risk of malignancy) and malignant in nine patients (39.1%). The remaining three patients had no ultrasound/mammography reports. Mean SUVmax of benign and malignant lesions were 2.6 ± 1.4 and 5.8 ± 3.5, respectively (P = 0.002). Considering a SUVmax cut-off value of 4.0, the sensitivity and specificity for differentiating benign vs. malignant lesions were 67 and 93%, respectively. Benign lesions were smaller than malignant in CT (maximum diameter:1.3 ± 0.5 cm vs. 2.0 ± 1.0 cm, P = 0.02).

CONCLUSION

Although BIU detected by 18F-FDG PET/CT is infrequently found, the risk of malignancy remains very high (39.1%). Both SUVmax and maximum diameter were greater in malignant than in benign lesions. An exhaustive study with ultrasound/mammography and selective histopathological correlation is mandatory after BIU findings, even in small lesions.

[Surgical treatment of esophageal cancer-Indicators for quality in diagnostics and treatment]

BACKGROUND

Within the framework of the quality initiative of the German Society for General and Visceral Surgery (DGAV) a review article was compiled based on a systematic literature search. Recommendations for the current diagnostics and treatment of esophageal cancer were also elaborated.

METHODS

The systematic literature search was carried out in March 2019 according to the PRISMA criteria using the MEDLINE databank. The recommendations were formulated based on a consensus in the DGAV.

RESULTS AND CONCLUSION

Operations below the currently valid minimum quantity threshold should no longer be carried out. There are many indications that the minimum quantity in Germany should be raised to ≥20 resections/year/hospital in order to comprehensively improve the quality. Prehabilitation programs with endurance, strength and intensive breathing training as well as nutritional therapy improve patient outcome. The current treatment of esophageal cancer is stage-dependent and incorporates endoscopic resection of (sub)mucosal low-risk tumors (T1m1-3 or T1sm1 low risk), primary esophagectomy of submucosal high-risk tumors (T1a), submucosal cancer (T1sm2-3) and T2N0 tumors, multimodal treatment with neoadjuvant chemoradiotherapy or perioperative chemotherapy and operations for advanced stages. Esophagectomy is nowadays carried out in one stage as a so-called hybrid procedure (laparoscopy and muscle-preserving thoracotomy) or as a total minimally invasive operation (laparoscopy and thoracoscopy).

Esophageal Cancer: Tumor-Node-Metastasis Staging

Esophageal cancer is an uncommon malignancy that ranks sixth in terms of mortality worldwide. Squamous cell carcinoma is the predominant histologic subtype worldwide whereas adenocarcinoma represents the majority of cases in North America, Australia, and Europe. Esophageal cancer is staged using the American Joint Committee on Cancer and the International Union for Cancer Control TNM system and has separate classifications for the clinical, pathologic, and postneoadjuvant pathologic stage groups. The determination of clinical TNM is based on complementary imaging modalities, including esophagogastroduodenoscopy/endoscopic ultrasound; endoscopic ultrasound-fine-needle aspiration; computed tomography of the chest, abdomen, and pelvis; and fluorodeoxyglucose PET/computed tomography.

Impact of PET/CT on management of patients with esophageal cancer - results from a PET/CT registry study

PURPOSE

To investigate the impact of positron emission tomography/computed tomography (PET/CT) on clinical management in patients with esophageal cancer and its link to overall survival (OS) in a real-world setting.

METHODS

A patient cohort with advanced esophageal cancer undergoing PET/CT was prospectively enrolled in a registry study between 04/2013 and 06/2019. Intended patient management prior and after PET/CT was documented based on standardized questionnaire data. Management changes after PET/CT were recorded including major changes concerning the treatment goal (curative vs. palliative) and minor changes (therapy adjustments). OS was analyzed for subgroups with squamous cell carcinomas (SCC) or adenocarcinomas (AC) and stratified for extent of metastatic disease and treatment goals.

RESULTS

257 patients (53 female;65.5 ± 10.0 yr.) were included. After PET/CT, major changes of intended therapy were observed in 34/257 patients (13.2%), from curative to palliative (8.2%), palliative to curative (1.9%) and from "not finally determined" to a curative (1.9%) or palliative (1.2%) concept. Minor changes were found in 62/257 patients (24.1%). Invasive procedures and additional imaging were intended in 70/257 (27.2%) and 94/257 (36.6%) patients before PET/CT and 20/257 (7.8%) and 8/257 (3.1%) patients after PET/CT. Curative therapy concepts based on PET/CT were associated with a longer OS (3.5 yr.[95%CI 3.1-3.8 yr.]) as compared to palliative concepts (0.9 yr.[95%CI 0.6-1.2 yr.];p < 0.0001). Patients with SCC had a worse prognosis (2.4 yr.[95%CI 2.0-2.9 yr.]) as compared to patients with AC (3.2 yr.[95%CI 2.7-3.7 yr.];p = 0.01).

CONCLUSIONS

In patients with advanced esophageal cancer, PET/CT has a significant impact on clinical management by improving the selection of individualized treatment strategies and avoiding additional diagnostic procedures.

Expression and Regulatory Network Analysis of MiR-139-3p, a New Potential Serum Biomarker for Esophageal Squamous Cell Carcinoma Based on Bioinformatics Analysis

Background:

In recent studies, microRNAs have been demonstrated as stable detectable biomarkers in blood for cancer. In addition, computer-aided biomarker discovery has now become an attractive paradigm for precision diagnosis.

Methods:

In this study, we identified and evaluated miR-139-3p as a biomarker for screening of esophageal squamous cell carcinoma using the Cancer Genome Atlas and Gene Expression Omnibus database analyses. We identified possible miR-139-3p target genes through the predicted database and esophageal squamous cell carcinoma upregulated genes from the Cancer Genome Atlas and Gene. Bioinformatics analysis was performed to determine key miR-139-3p targets and pathways associated with esophageal carcinoma. Finally, the expression and expected significance of hub genes were evaluated via the Genotype-Tissue Expression project.

Results:

MiR-139-3p was significantly downregulated in patients with esophageal squamous cell carcinoma/esophageal carcinoma. In GSE 122497, the area under the curve-receiver operating characteristic value, sensitivity, and specificity for serum miR-139-3p were 0.754, 67.49%, and 80.00%, respectively. The pattern specification process, skeletal system development, and regionalization process were the most enriched interactions in esophageal carcinoma. In addition, Epstein-Barr virus infection, human T-cell leukemia virus 1 infection, and human cytomegalovirus infection were identified as crucial pathways. Six hub genes (CD1A, FCGR2A, ANPEP, CD1B, membrane metalloendopeptidase, and TWIST1) were found, and FCGR2A and membrane metalloendopeptidase were further confirmed by genotype-tissue expression. High expression of membrane metalloendopeptidase correlated with a better overall survival but not with disease-free survival of patients with esophageal carcinoma.

Conclusions:

MiR-139-3p was identified as a candidate biomarker for predicting esophageal squamous cell carcinoma based on network analysis. MiR-139-3p acted as a tumor suppressor by targeting membrane metalloendopeptidase in esophageal carcinoma, and low expression of membrane metalloendopeptidase may indicate a better prognosis of patients with esophageal carcinoma.

The PET-Derived Tumor-to-Liver Standard Uptake Ratio (SUV TLR ) Is Superior to Tumor SUVmax in Predicting Tumor Response and Survival After Chemoradiotherapy in Patients With Locally Advanced Esophageal Cancer

Background: The maximum standardized uptake values (SUVmax) derived from ¹⁸F-fluorodeoxy-glucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) have some well-known shortcomings in predicting treatment response and prognosis in oncology. The standardized SUVmax with an appropriate reference background may overcome this problem in some instances. This study explored the prognostic value of the tumor-to-liver SUVmax ratio (SUV_TLR) and the tumor-to-blood pool SUVmax ratio (SUV_TBR) in predicting the objective response (OR) and overall survival (OS) in patients with locally advanced esophageal cancer after concurrent chemoradiotherapy (CCRT).

Methods: We retrospectively analyzed 128 newly diagnosed esophageal squamous cell carcinoma (ESCC) patients who were treated with CCRT. The SUVmax of primary tumor, SUV_TLR, SUV_TBR and clinicopathologic features data were analyzed. Univariate and multivariate analyses were used to determine the predictors of tumor response. Survival analysis was performed using the Kaplan–Meier method and Cox proportional hazards model.

Results: Receiver operating characteristic (ROC) curve analysis demonstrated that SUV_TLR was superior to SUVmax and SUV_TBR in predicting treatment response. Univariate and multivariate analyses revealed that advanced tumor stage (hazard ratio [HR] = 9.67; 95% CI: 1.15-81.28; P = 0.037) and high SUV_TLR (HR = 21.92; 95% CI: 2.26-212.96; P = 0.008) were independent predictors of poor treatment response. Cox regression analysis showed that good clinical tumor response (p < 0.014, HR =0.501; 95% CI: 0.288–0.871) was a favorable independent predictive factor for OS, while an advanced tumor stage (p = 0.018, HR = 1.796; 95% CI: 1.107-2.915) and a high SUV_TLR (p < 0.002, HR = 2.660; 95% CI: 1.425–4.967) were prognostic factors for poor OS. The median OS of patients in the low SUV_TLR and high SUV_TLR groups was 13.47 vs. 19.30 months, respectively.

Conclusions: PET-derived SUV_TLR is superior to tumor SUVmax and SUV_TBR in predicting treatment response and overall survival in patients with ESCC undergoing CCRT. High SUV_TLR was an independent predictor of poor treatment response and shorter overall survival.

DNA methylation-mediated repression of exosomal miR-652-5p expression promotes oesophageal squamous cell carcinoma aggressiveness by targeting PARG and VEGF pathways

Exosomal microRNAs (miRNAs) have been recently shown to play vital regulatory and communication roles in cancers. In this study, we showed that the expression levels of miR-652-5p in tumour tissues and serum samples of oesophageal squamous cell carcinoma (OSCC) patients were lower compared to non-tumorous tissues and serum samples from healthy subjects, respectively. Decreased expression of miR-652-5p was correlated with TNM stages, lymph node metastasis, and short overall survival (OS). More frequent CpG sites hypermethylation in the upstream of miR-652-5p was found in OSCC tissues compared to adjacent normal tissues. Subsequently, miR-652-5p downregulation promoted the proliferation and metastasis of OSCC, and regulated cell cycle both in cells and in vivo. The dual-luciferase reporter assay confirmed that poly (ADP-ribose) glycohydrolase (PARG) and vascular endothelial growth factor A (VEGFA) were the direct targets of miR-652-5p. Moreover, the delivery of miR-652-5p agomir suppressed tumour growth and metastasis, and inhibited the protein expressions of PARG and VEGFA in nude mice. Taken together, our findings provide novel insight into the molecular mechanism underlying OSCC pathogenesis.

Opportunistic body composition evaluation in patients with esophageal adenocarcinoma: association of survival with 18F-FDG PET/CT muscle metrics

OBJECTIVE

¹⁸F-FDG PET is widely used to accurately stage numerous types of cancers. Although ¹⁸F-FDG PET/CT features of tumors aid in predicting patient prognosis, there is increasing interest in mining additional quantitative body composition data that could improve the prognostic power of ¹⁸F-FDG PET/CT, without additional examination costs or radiation exposure. The aim of this study was to determine the association between overall survival and body composition metrics derived from routine clinical ¹⁸F-FDG PET/CT examinations.

METHODS

Patients who received baseline ¹⁸F-FDG PET/CT imaging during workup for newly diagnosed esophageal adenocarcinoma (EAC) were included. From these studies, psoas cross-sectional area (CSA), muscle attenuation (MA), SUV_mean, and SUV_max were obtained. Correlation with overall survival was assessed using a Cox Proportional Hazards model, controlling for age, body mass index, ¹⁸F-FDG dose, glucose level, diabetes status, in-hospital status, and tumor stage.

RESULTS

Among the 59 patients studied, psoas MA and SUV_max were found to be significant predictors of survival (HR 0.94, 95% CI 0.88-0.99, p = 0.04, and HR 0.37, 95% CI 0.14-0.97, p = 0.04, respectively) and remained independent predictors. Psoas CSA and SUV_mean did not significantly influence survival outcomes.

CONCLUSIONS

Characterization of psoas muscles as a surrogate marker for sarcopenia on baseline ¹⁸F-FDG PET/CT imaging is relatively easily obtained and may offer additional prognostic value in patients with EAC.

Pattern of use of positron emission tomography/computed tomography (PET/CT) scan in non-colorectal gastrointestinal cancers at KFSHRC, Riyadh, Saudi Arabia

Background

Positron emission tomography/computed tomography (PET/CT) scan is useful if clinically indicated. It is not for conventional routine use due to its high cost. Moreover, it can be confusing if ordered in non-indicated conditions. We evaluate if the pattern of PET/CT ordered in gastrointestinal cancers (non-colorectal origin) has followed evidence-based guidelines and whether it helped in the improvement of patient’s outcome. This study included non-colorectal gastrointestinal cancer patients from 2007 to 2008 who had one or more PET/CT scans done during their management. In each case, data collected revealed whether PET/CT affected the management or the stage or not. Patients were identified through the hospital tumor registry software CNExT (C/NET Solutions, Berkeley, CA). Tabulation and statistical data analysis were done using JMP-SAS statistical software application (version 9.4: SAS Institute, Cary, NC, USA). The scan report quality and use indications were outlined.

Results

Seventy-seven patients were identified, with 107 PET/CT scans done. Their median age is 59 (21–86) years. Males were 45 (58.5%). Tumor origin was 46.8% esophageal and gastroesophageal junction cancer, 15.6% gastric cancer, 11.7% pancreatic cancer, 11.7% hepatobiliary tumors, 10.4% neuroendocrine tumors, 2.6 % gastrointestinal stromal tumors, and 1.3% small bowel cancer. Indications of the PET/CT were as follows: staging in 59.8%, follow-up after finishing treatment in 14.9%, restaging at relapse in 8.4%, assessing response after/during treatment in 3.7%, follow-up of previous PET/CT in 12.1%, and others in 0.9%. PET/CT changed the stage in 19.6% and affected the management plan in 11.2% only. Fifty-two scans needed pathological pursuit as decided by investigators; of them, PET/CT for the lesions that could have changed the stage reported indeterminate/equivocal results in 32 (29.9%) of all scans. The pathological pursuit for the equivocal lesions on PET/CT scans was done in only 12 of 52 (23.1%) scans.

Conclusions

Local guidelines for ordering PET/CT scan are suggested because overuse was documented, and an evidence-based approach should be respected before its use.

Staging and Response Evaluation to Neo-Adjuvant Chemoradiation in Esophageal Cancers Using 18FDG PET/ CT with Standardized Protocol

Background:

Precise staging of esophageal cancer (EC) is important for selection of optimal treatment option and prognostication. Aim of this study was to assess the role of ¹⁸FDG PET/CT in staging and response evaluation to neoadjuvant chemoradiation (nCR) in EC patients using standardized imaging protocol.

Material and methods:

This prospective study was conducted at PET/CT Section of Department of Radiology, Aga Khan University Hospital Karachi, Pakistan from July 2017 till February 2018. We included 34 biopsy proven EC patients who had ¹⁸FDG PET/CT and CT of neck, chest and abdomen as part of initial staging. Eleven patients had post-nCR ¹⁸FDG PET/CT using standardized imaging protocol as per EANM guidelines. CT and PET/CT based staging was compared. Based on PERCIST criteria, response evaluation was assessed using change in highest SUVmax (%∆SUVmax) in baseline and follow-up scans (primary lesion, node or extra-nodal metastases).

Results:

Mean age of cohort was 57 ± 14 years (23 males and 11 females) having adenocarcinoma (AC) in 23 and squamous cell cancer (SCC) in 11 patients. Mean ¹⁸FDG dose, uptake time and hepatic SUVmean for baseline scans were 169 ±54 MBq, 65 ±10 minute and 1.91 ± 0.49 which were within ± 10%, ± 15% and ± 20% for follow-up scans in 11 patients respectively. Mean size (craniocaudal dimension in mm) and SUVmax of primary tumor was 56 ±27 mm and 13.4 ± 4.7. Based on ¹⁸FDG PET/CT findings, patients were categorized into N0 (10/34), N1 (09/34), N2 (11/34) and N3 (04/34) while 11/32 had stage IV disease. No significant difference was seen in AC and SCC groups. CT found stage IV disease in 3/34 (09%) while PET/CT found in 11/34 (32%; p value: 0.019) cases. PET/CT showed concordance with CT in 41% while discordance (all with upstaging) seen in 59%. On follow-up PET/CT, complete metabolic response was seen in 5/11 (45%) and partial metabolic response was noted in 6/11 (55% - p value non-significant) patients. Median %∆SUVmax over primary lesions was 49.84% (-32.69 -100%) while over nodal sites it was 41.18% (-82.60 -100%).

Conclusion:

We conclude that ¹⁸FDG PET/CT was found a sensitive tool in initial staging of EC. Compared with CT, it had higher diagnostic accuracy for distant nodal and extra-nodal metastasis. %∆SUVmax between baseline and post-nCR studies acquired with standardized protocol had changed management in more than half of our patients. For response evaluation in EC more studies with standardized ¹⁸FDG PET/CT imaging protocols are warranted.

Improved detection of metastatic lymph nodes in oesophageal squamous cell carcinoma by combined interpretation of fluorine-18-fluorodeoxyglucose positron-emission tomography/computed tomography

Background

We sought to evaluate the diagnostic performance of fluorine-18-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT) in the detection of metastatic lymph nodes by combined interpretation of PET/CT images in patients with oesophageal squamous cell carcinoma.

Methods

Two hundred three patients with oesophageal squamous cell carcinoma underwent ¹⁸F-FDG PET/CT before oesophagectomy and lymph node dissection. Maximum standardized uptake value (SUV_max), mean Hounsfield unit (HU), short axis diameter (size), and visual CT attenuation (high, iso-, low) were evaluated on noncontrast CT and PET images following PET/CT scan. In this combined interpretation protocol, the high attenuated lymph nodes were considered benign, even if the SUV_max value was high. The diagnostic accuracy of each method was compared using the postoperative histologic result as a reference standard.

Results

A total of 1099 nodal stations were dissected and 949 nodal stations were proven to demonstrate metastasis. SUV_max and size of the malignant lymph nodes were higher than those of the benign nodes, and visual CT attenuation was significantly different among the two groups (P < 0.001). Using cutoff values of 2.6 for SUV_max and 10.2 mm for size, the combined interpretation of an SUV_max of more than 2.6 with iso- or low CT attenuation [area under the curve (AUC): 0.846, 95% confidence interval (CI): 0.824–0.867] showed significantly better diagnostic performance for detecting malignant lymph nodes than SUV_max only (AUC: 0.791, 95% CI: 0.766–0.815) and size (AUC: 0.693, 95% CI: 0.665–0.720) methods (P < 0.001) in a receiver operating characteristic curve analysis.

Conclusions

The diagnostic accuracy of PET/CT for nodal metastasis in oesophageal squamous cell carcinoma was improved by the combined interpretation of ¹⁸F-FDG uptake and visual CT attenuation pattern.

Detection of additional primary malignancies: the role of CT and PET/CT combined with multiple percutaneous biopsy

Objective

To evaluate the imaging findings of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and computed tomography (CT) in patients with additional primary tumors, correlating the results with those of the method used in order to elucidate the diagnosis and of the pathology reports.

Materials and Methods

We retrospectively analyzed the medical records, pathology reports and images of 11 patients who underwent CT, ¹⁸F-FDG PET/CT, or both. We included patients with at least two tumors, with confirmed distinct histopathological profiles, at different sites. Patients in whom there was no diagnostic confirmation were excluded, as were those in whom the additional lesion was suspected of being a metastasis of the first.

Results

New primary malignancies were identified in 11 patients, one new tumor being found in 10 and two new tumors being found in 1. The confirmed sites of the additional malignancies were the lung, kidney, prostate, jejunum, and breast. Single or multiple percutaneous biopsies were performed in 10 patients, and 1 patient underwent a surgical procedure for diagnostic and therapeutic purposes. The tumors were metachronous in 6 cases and synchronous in 5.

Conclusion

CT and ¹⁸F-FDG PET-CT combined with multiple percutaneous biopsy could facilitate the diagnosis of additional lesions, thus optimizing the treatment and follow-up of the affected patients.

Radiomics in esophageal and gastric cancer

Esophageal, esophago-gastric, and gastric cancers are major causes of cancer morbidity and cancer death. For patients with potentially resectable disease, multi-modality treatment is recommended as it provides the best chance of survival. However, quality of life may be adversely affected by therapy, and with a wide variation in outcome despite multi-modality therapy, there is a clear need to improve patient stratification. Radiomic approaches provide an opportunity to improve tumor phenotyping. In this review we assess the evidence to date and discuss how these approaches could improve outcome in esophageal, esophago-gastric, and gastric cancer.

FDG-PET might not contribute to improving survival in patients with locally advanced inoperable esophageal cancer

BACKGROUND

In Japan, positron emission tomography using ¹⁸F-fluorodeoxyglucose (FDG-PET) has been covered by the national health insurance for esophageal cancer since 2006. FDG-PET is commonly performed in advanced esophageal cancer. The aim of this study was to determine the effect of FDG-PET on survival in patients with locally advanced inoperable esophageal cancer.

METHODS

We retrospectively reviewed all patients with cT4 and without M1 esophageal cancer on CT in our institution between 2000 and 2014, and data for 78 patients who meet the eligibility criteria described below were used for analysis in this study. The eligibility criteria included (1) cT4 esophageal cancer without distant metastases or M1 lymph node metastasis (UICC 2002), (2) histologically proven squamous cell carcinoma, (3) 20-79 years of age, (4) having undergone at least 1 cycle of concomitant chemotherapy, (5) having been irradiated with 50 Gy or more, and (6) no other active malignant tumor during treatment.

RESULTS

Two patients were excluded because abdominal lymph node metastases or neck lymph node metastases were detected by FDG-PET. In 78 eligible patients, FDG-PET was not performed before treatment in 41 of the 78 patients and was performed in the other patients. The median observation period was 68 months. The 3-year and 5-year overall survival rates in 78 patients were 36.9% and 30.8%, respectively. There was no significant difference in overall survival or progression-free survival between patients in whom FDG-PET was performed and those in whom FDG-PET was not performed (12.0 months vs. 11.0 months, p = 0.920 and 6.0 months vs. 6.0 months, p = 0.844, respectively).

CONCLUSIONS

Compared with only CT, additional information from FDG-PET is not associated with improving survival in patients with locally advanced esophageal cancer. Our results suggest that FDG-PET might not have much meaning for survival in locally advanced esophageal cancer.

Present and future roles of FDG-PET/CT imaging in the management of gastrointestinal cancer: an update

Positron emission tomography/computed tomography (PET/CT) integrated with 2-[¹⁸F]fluoro-2-deoxy-D-glucose (FDG) is a useful tool for acquisition of both glucose metabolism and anatomic imaging data, as only a single device and one diagnostic session is required, thus opening a new field in clinical oncologic imaging. FDG-PET/CT has been successfully used for initial staging, restaging, assessment of early treatment response, evaluation of metastatic disease response, and prognostication of intestinal cancer as well as various malignant tumors. We reviewed the current status and role of FDG-PET/CT for management of patients with esophageal cancer, gastric cancer, and colorectal cancer, with focus on both its usefulness and limitations.

Understanding the Association of Axillary Lymph Node Metastasis in Esophageal Cancers

Lymph node metastasis is widely believed to be one of the most powerful prognostic factors influencing the outcomes of many solid cancers, including esophageal cancers. The left supraclavicular node, famously described as the Virchow's node, is occasionally involved in patients with advanced gastrointestinal cancers. Virchow node involvement is considered “nonregional” in all the gastrointestinal cancers, except in esophageal cancers. On the other hand, axillary lymph node metastases (ALNMs) are considered “nonregional” in all gastrointestinal cancers, including esophageal cancers. Exceptionally, some experts share a contrarian view and consider ALNM and supraclavicular lymph node metastasis to represent a contiguous regional dissemination of esophageal cancer. The clinical presentation of ALNM in the vast majority of the patients with esophageal cancers has been reported to be metachronous. Synchronous presentation is exceedingly rare, and our patient is possibly the second case to be reported in the English language literature. The increasing role of ¹⁸F-fluorodeoxyglucose positron emission tomography computed tomography scans in aiding the staging workup in patients with esophageal cancers and ultimately influencing the choice of management in such rare scenarios is further discussed.

A Resected Case of Primary Malignant Melanoma of the Esophagus—Early Detection of Recurrence by FDG-PET/CT

Primary malignant melanoma of the esophagus (PMME) is a rare, aggressive, therapy-resistant malignant tumor arising from esophageal mucosal melanocytes. It has been reported that fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has a clinical impact on PMME diagnosis; however, it remains unclear whether postoperative surveillance using FDG-PET/CT is useful for PMME patients. In this case study, FDG-PET/CT detected the recurrent tumors in their early stage after a curative resection of PMME. We report on a case of a 67-year-old Japanese male admitted to our hospital for the evaluation of polypoid tumors of the esophagogastric junction, which were diagnosed as PMME. He was treated with a curative resection by esophagectomy and 6 cycles of adjuvant chemotherapy of DAV (dacarbazine, nimustine, and vincristine). However, the PMME recurred 26 months after the surgery when surveillance FDG-PET/CT detected the recurrent tumors in their early stage. FDG-PET/CT may be useful to detect recurrence in the postoperative surveillance phase for PMME patients.

Diagnostic and Prognostic Value of Circulating MicroRNAs for Esophageal Squamous Cell Carcinoma: a Systematic Review and Meta-analysis

Background and Aim: MicroRNAs, dysregulated in the circulation of esophageal squamous cell carcinoma (ESCC) patient, have been assumed to be with great potential in the diagnosis and prognosis of esophageal cancer. We aimed to review previous articles on ESCC. Methods: A search of electronic databases was performed before Nov 12, 2017. We summarized the identification of microRNA imbalance in the blood of ESCC compared with the healthy controls, with the objective to evaluate the efficiency of microRNAs in diagnosing and forecasting ESCC. Results: A total of 35 studies investigating plasma or serum microRNAs were included in the meta-analysis. Based on the consequences of the quality assessment of each study, the articles involved were appropriate for quantitative synthesis. For diagnostic meta-analysis. The overall pooled sensitivity, specificity, and area under the curve of circulating microRNA is 0.794 (95% CI: 0.765 - 0.820), 0.779 (95%CI: 0.746 - 0.808), 0.86 (95%CI: 0.82 - 0.88). The diagnostic value of each microRNA was calculated respectively. For prognostic meta-analysis, the overall pooled hazard ratios of higher microRNA expression in circulation was 1.34 (95% CI: 1.14-1.58), which could significantly predict poorer survival in ESCC. Conclusions: Circulating microRNAs distinguish patients with ESCC from healthy controls with high sensitivity and specificity, compared to other invasive currently used screening methods. Simultaneously, there was prognostic value for the prognosis of ESCC.

[New S3 guideline for esophageal cancer : Important surgical aspects]

The current German S3 guideline represents the recommendations for the diagnosis and therapy of squamous cell carcinomas and adenocarcinomas of the esophagus based on evidence from the literature and interdisciplinary expert consensus. Esophagogastroscopy with biopsy, endosonography, and spiral CT scan of the neck, thorax, and abdomen are decisive in staging and the choice of therapy. For a curative approach, surgery, especially transthoracic esophagectomy and gastric pull-up, is the most important therapeutic option, except in the case of mucosal carcinomas or cervical squamous cell carcinomas. The significance of total minimally invasive esophageal resection or a hybrid technique is still uncertain. In category cT3 or resectable cT4 tumors, neoadjuvant radiochemotherapy should be performed in squamous cell carcinomas or adenocarcinomas. Alternatively, perioperative chemotherapy can be carried out in adenocarcinoma. Palliative resections should be avoided and replaced by interventional procedures for palliation.

Meta-analysis of microRNAs as potential biomarkers for detecting esophageal carcinoma in Asian populations

BACKGROUND:

An Increasing number of studies in the literature have shown that microRNAs (miRNAs) can be used as early diagnostic markers for esophageal carcinoma (EC), but their conclusions remain controversial. Hence, we performed this meta-analysis to evaluate the diagnostic accuracy of using miRNAs in EC and to provide an experimental basis for early diagnosis of the disease.

METHODS:

This meta-analysis included 39 Asian studies from 18 articles, which covered 3,708 EC patients and 2,689 healthy controls. We used a bivariate random-effects model, the chi-square test and the I² test to assess sensitivity and heterogeneity.

RESULTS:

Pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of miRNAs for diagnosis of EC in Asians reached 0.798, 0.785, 3.705, 0.257 and 14.391, respectively. Additionally, the area under the summary receiver operating characteristic curve was 0.86. Subgroup analysis based on research country (China vs. Japan), sample types (plasma vs. serum) and miRNAs (single vs. multiple; singly reported miRNAs vs. repeatedly reported miRNAs) showed no significant difference in accuracy of diagnosis for each subgroup.

CONCLUSIONS:

MiRNAs can distinguish EC patients from healthy controls. Blood-based miRNAs have better diagnostic value in detecting EC than saliva-based miRNAs, whereas both serum and plasma are recommended for clinical specimens for miRNA detection.

Interim 18F-FDG-PET/CT during chemo-radiotherapy in the management of oesophageal cancer patients. A systematic review

Oesophageal cancer is an aggressive disease. The possibility to early stratify patients as responsive and non-responsive with a non-invasive method is extremely appealing. The uptake of Fluorodeoxyglucose (¹⁸F-FDG) in tumours, provided by positron emission tomography (PET) images, has been proved to be useful to assess the initial staging of the disease, recurrence, and response to chemotherapy and chemo-radiotherapy (CRT). In the last years, efforts have been focused on the possibility to use ad interim ¹⁸F-FDG-PET/CT (PET_int) to evaluate response during radiation therapy. However, controversial findings have been reported, although some relevant results would support its use for individual therapeutic decision. The present review assembles the comprehensive literature of the last decade to evaluate whether and in which cases PET_int may offer predictive potential in oesophageal cancer. All the analysed studies (13 studies, 697 patients) denoted PET_int as a challenging examination for early assessment of outcomes during CRT. In particular, 8 studies advocated the predictivity of PET_int, whilst 5 did not find any correlation between the interim variation of PET parameters and the pathological complete response and/or the clinical outcome. The reasons that possibly have caused contradictions among the studies demand further research with prospective and uniform protocols and methods of analysis to assess the predictive and prognostic value of PET_int in oesophageal cancer.

PET/Computed Tomography Scanning and Precision Medicine: Esophageal Cancer

Esophageal cancer commonly has a poor prognosis, which requires an accurate diagnosis and early treatment to improve outcome. Other modalities for staging, such as endoscopic ultrasound imaging and computed tomography (CT) scans, have a role in diagnosis and staging. However, PET with fluorine-18 fluoro-2-deoxy-d-glucose/CT (FDG PET/CT) scanning allows for improved detection of distant metastatic disease and can help to prevent unnecessary interventions that would increase morbidity. FDG PET/CT scanning is valuable in the neoadjuvant chemotherapy assessment and predicting survival outcomes subsequent to surgery. FDG PET/CT scanning detects recurrent disease and metastases in follow-up.

Current clinical status of 18F-FLT PET or PET/CT in digestive and abdominal organ oncology

Positron emission tomography (PET) or PET/computed tomography (CT) using ¹⁸F-3'-fluoro-3'-deoxythymidine (¹⁸F-FLT) offers noninvasive assessment of cell proliferation in human cancers in vivo. The present review discusses the current status on clinical applications of ¹⁸F-FLT-PET (or PET/CT) in digestive and abdominal oncology by comparing with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG)-PET (or PET/CT). The results of this review show that although ¹⁸F-FLT uptake is lower in most cases of digestive and abdominal malignancies compared with ¹⁸F-FDG uptake, ¹⁸F-FLT-PET can be used to detect primary tumors. ¹⁸F-FLT-PET has shown greater specificity for N staging than ¹⁸F-FDG-PET which can show false-positive uptake in areas of inflammation. However, because of the high background uptake in the liver and bone marrow, it has a limited role of assessing liver and bone metastases. Instead, ¹⁸F-FLT-PET will be a powerful tool for monitoring response to treatment and provide prognostic information in digestive and abdominal oncology.

Application of PET/CT in gastrointestinal cancers

Fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography (¹⁸F-FDG PET) is an imaging tool which reflects tumor metabolism. The integration of PET with computed tomography (CT) can provide precise anatomical information along with metabolic data. Here, we review the application and potential role of ¹⁸F-FDG PET/CT imaging in staging, evaluation of chemoradiation therapy, and detection of recurrence in gastrointestinal cancers.

Functional imaging in liver tumours

Functional imaging encompasses techniques capable of assessing physiological parameters of tissues, and offers useful clinical information in addition to that obtained from morphological imaging. Such techniques may include magnetic resonance imaging with diffusion-weighted sequences or hepatobiliary contrast agents, perfusion imaging, or molecular imaging with radiolabelled tracers. The liver is of major importance in oncological practice; not only is hepatocellular carcinoma one of the malignancies with steadily rising incidence worldwide, but hepatic metastases are regularly observed with a range of solid neoplasms. Within the realm of hepatic oncology, different functional imaging modalities may occupy pivotal roles in lesion characterisation, treatment selection and follow-up, depending on tumour size and type. In this review, we characterise the major forms of functional imaging, discuss their current application to the management of patients with common primary and secondary liver tumours, and anticipate future developments within this field.

Comparison of characteristics of 18F-fluorodeoxyglucose and 18F-fluorothymidine PET during staging of esophageal squamous cell carcinoma

OBJECTIVES

The aim of this study was to compare the characteristics derived from fluorine-18 fluorodeoxyglucose (F-FDG) and fluorine-18 fluorothymidine (F-FLT) PET quantitatively and to assess their capacities during staging of esophageal squamous cell carcinoma (ESCC).

MATERIALS AND METHODS

Thirty-six patients with a diagnosis of ESCC who underwent both F-FDG and F-FLT PET were included in this study. Different image-derived indices including the standardized uptake value (SUV), gross tumor length, and texture features were determined. Considering histopathologic examination as the gold standard, the performance of the extracted indices during staging of ESCC was assessed using the Kruskal-Wallis test and the Mann-Whitney test.

RESULTS

Considering the F-FDG PET images, the SUVmax, SUVmean, length (LEN), and eccentricity (EC) were significant during staging of American Joint Committee on Cancer (AJCC) and TNM (P<0.01), whereas for the F-FLT image, the SUVmax, LEN, and EC were significant during staging of AJCC and TNM (P<0.01). The characteristics of F-FDG and F-FLT PET for the classification of ESCC stage were significantly different.

CONCLUSION

F-FDG image-derived characteristics including image textural features, SUV, and shape feature allow for better stratification of AJCC and TNM than F-FLT PET in ESCC patients.

Role of Pre-therapeutic (18)F-FDG PET/CT in Guiding the Treatment Strategy and Predicting Prognosis in Patients with Esophageal Carcinoma

OBJECTIVES

The present study aimed to evaluate the role of pre-therapeutic (18)fluorine-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG PET-CT) and maximum standardized uptake value (SUVmax) in guiding the treatment strategy and predicting the prognosis of esophageal carcinoma, using the survival data of the patients.

METHODS

The present retrospective, cohort study was performed on 40 consecutive patients with esophageal carcinoma (confirmed by endoscopic biopsy), who underwent pre-operative (18)F-FDG PET-CT staging between January 2009 and June 2014. All the patients underwent contrast-enhanced CT and non-contrasted (18)F-FDG PET-CT evaluations. The patients were followed-up over 12 months to assess the changes in therapeutic strategies. Survival analysis was done considering the primary tumor SUVmax, using the Kaplan-Meier product-limit method.

RESULTS

In a total of 40 patients, (18)F-FDG PET-CT scan led to changes in disease stage in 26 (65.0%) cases, with upstaging and downstaging reported in 10 (25.0%) and 16 (40.0%) patients, respectively. The management strategy changed from palliative to curative in 10 out of 24 patients and from curative to palliative in 7 out of 16 cases. Based on the (18)F-FDG PET-CT scan alone, the median survival of patients in the palliative group was 4.0 (95% CI 3.0-5.0) months, whereas the median survival in the curative group has not been reached, based on the 12-month follow-up. Selection of treatment strategy on the basis of (18)F-FDG PET/CT alone was significantly associated with the survival outcomes at nine months (P=0.03) and marginally significant at 12 months (P=0.03). On the basis of SUVmax, the relation between survival and SUVmax was not statistically significant.

CONCLUSION

(18)F-FDG PET/CT scan had a significant impact on stage stratification and subsequently, selection of a stage-specific treatment approach and the overall survival outcome in patients with esophageal carcinoma. However, pre-treatment SUVmax failed to stablish its usefulness in the assessment of patient prognosis and survival outcome.

Insights into the potential use of microRNAs as a novel class of biomarkers in esophageal cancer

MicroRNAs (abbreviated miRNAs) have been demonstrated to be involved in tumorigenesis and cancer development and proposed as promising biomarkers in cancer diagnosis. Numerous studies have observed the aberrant expression of miRNAs in esophageal cancer. However, there are some discrepant results. Thus, we conducted this meta-analysis to identify the overall accuracy of miRNAs in the diagnosis of esophageal cancer. A comprehensive literature search was conducted in PubMed and other databases using combinations of key words. The summary receiver operator characteristic curves were plotted to assess the overall diagnostic performance of miRNAs. Chi-squared and I(2) tests were used to assess the heterogeneity between studies. Additionally, we conducted subgroup and sensitivity analyses to analyze the potential sources of heterogeneity. In total, 33 studies from 12 articles were available in this meta-analysis. The pooled sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR) diagnostic odds ratio, and area under the curve were 0.80, 0.80, 4.0, 0.25, 16, and 0.87, respectively. Subgroup analyses based on the sample types (saliva-, serum- and plasma-based) showed no differences in the diagnostic accuracy of each subgroup. An independent meta-analysis of eight articles was conducted to evaluate the diagnostic accuracy of miRNAs in patients with esophageal squamous cell carcinoma, with a pooled sensitivity of 0.77, specificity of 0.83, PLR of 4.4, NLR of 0.27, diagnostic odds ratio of 16, and area under the curve of 0.87. In conclusion, this meta-analysis demonstrates the feasibility of using miRNAs as non-invasive biomarkers to discriminate esophageal cancer from healthy controls. However, further high-quality studies on more clearly defined esophageal cancer patient are needed to confirm our conclusion.

Superiority of Deformable Image Co-registration in the Integration of Diagnostic Positron Emission Tomography-Computed Tomography to the Radiotherapy Treatment Planning Pathway for Oesophageal Carcinoma

AIMS

To investigate the use of image co-registration in incorporating diagnostic positron emission tomography-computed tomography (PET-CT) directly into the radiotherapy treatment planning pathway, and to describe the pattern of local recurrence relative to the PET-avid volume.

MATERIALS AND METHODS

Fourteen patients were retrospectively identified, six of whom had local recurrence. The accuracy of deformable image registration (DIR) and rigid registration of the diagnostic PET-CT and recurrence CT, to the planning CT, were quantitatively assessed by comparing co-registration of oesophagus, trachea and aorta contours. DIR was used to examine the correlation between PET-avid volumes, dosimetry and site of recurrence.

RESULTS

Positional metrics including the dice similarity coefficient (DSC) and conformity index (CI), showed DIR to be superior to rigid registration in the co-registration of diagnostic and recurrence imaging to the planning CT. For diagnostic PET-CT, DIR was superior to rigid registration in the transfer of oesophagus (DSC=0.75 versus 0.65, P<0.009 and CI=0.59 versus 0.48, P<0.003), trachea (DSC=0.88 versus 0.65, P<0.004 and CI=0.78 versus 0.51, P<0.0001) and aorta structures (DSC=0.93 versus 0.86, P<0.006 and CI=0.86 versus 0.76, P<0.006). For recurrence imaging, DIR was superior to rigid registration in the transfer of trachea (DSC=0.91 versus 0.66, P<0.03 and CI=0.83 versus 0.51, P<0.02) and oesophagus structures (DSC=0.74 versus 0.51, P<0.004 and CI=0.61 versus 0.37, P<0.006) with a non-significant trend for the aorta (DSC=0.91 versus 0.75, P<0.08 and CI=0.83 versus 0.63, P<0.06) structure. A mean inclusivity index of 0.93 (range 0.79-1) showed that the relapse volume was within the planning target volume (PTVPET-CT); all relapses occurred within the high dose region.

CONCLUSION

DIR is superior to rigid registration in the co-registration of PET-CT and recurrence CT to the planning CT, and can be considered in the direct integration of PET-CT to the treatment planning process. Local recurrences occur within the PTVPET-CT, suggesting that this is a suitable target for dose-escalation strategies.

Oesophageal squamous cell carcinoma (ESCC): Advances through omics technologies, towards ESCC salivaomics

Oesophageal Squamous Cell Carcinoma (ESCC) is one of the two main subtypes of oesophageal cancer, affecting mainly populations in Asia. Though there have been great efforts to develop methods for a better prognosis, there is still a limitation in the staging of this affection. As a result, ESCC is detected at advances stages, when the interventions on the patient do not have such a positive outcome, leading in many cases to recurrence and to a very low 5-year survival rate, causing high mortality. A way to decrease the number of deaths is the use of biomarkers that can trace the advance of the disease at early stages, when surgical or chemotherapeutic methodologies would have a greater effect on the evolution of the subject. The new high throughput omics technologies offer an unprecedented chance to screen for thousands of molecules at the same time, from which a new set of biomarkers could be developed. One of the most convenient types of samples is saliva, an accessible body fluid that has the advantage of being non-invasive for the patient, being easy to store or to process. This review will focus on the current status of the new omics technologies regarding salivaomics in ESCC, or when not evaluated yet, the achievements in related diseases.

Prognostic significance of PET assessment of metabolic response to therapy in oesophageal squamous cell carcinoma

Objectives:

The role of maximum standard uptake value (SUVmax) at baseline and after induction chemotherapy (CT) on positron emission tomography (PET) as an imaging biomarker has not been well established in oesophageal squamous cell carcinoma (SCC). In this retrospective analysis, we investigated the prognostic significance of various PET metrics in oesophageal SCC patients treated with induction chemotherapy followed by concurrent chemoradiotherapy (CRT).

Methods:

A total of 57 patients were treated with CRT; 52 patients received induction chemotherapy and 10 patients underwent surgery following CRT. Scans were independently analysed by a nuclear medicine physician blinded to patient outcome. Using region of interest analysis, SUVmax and metabolic tumour volume (MTV) were calculated for the index lesion and lymph node metastases in each patient. Kaplan–Meier analysis was used to evaluate overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS). Cox proportional hazards regression was used to assess correlation between outcomes and PET metrics.

Results:

Median follow-up for those who are alive was 4.4 years, with a median survival for all patients of 2.9 years. The 3-year OS, DFS, DMFS and LRFS rates were 47, 40, 44 and 36%, respectively. Using a pre-established cutoff of a 35% decrease in SUVmax from baseline to post-induction PET, 3-year OS for responders (⩾35% decrease from baseline) was 64%, whereas non-responders (<35% decrease from baseline) had a 3-year OS of 15% (P=0.004).

Conclusions:

The pre-specified 35% decrease in SUVmax after induction chemotherapy was prognostic for OS. Baseline and post-induction PET metrics provide prognostic information for oesophageal SCC.