Positron emission tomography changes management and prognostic stratification in patients with oesophageal cancer: results of a multicentre prospective study

Position statement of the World Endoscopy Organization: Role of endoscopy in screening, diagnosis, and treatment of esophageal superficial squamous neoplasiaia

Esophageal squamous cell carcinoma (ESCC) remains a significant global health challenge, being the sixth leading cause of cancer mortality with pronounced geographic variability. The incidence rates range from 125 per 100,000 in northern China to 1-1.5 per 100,000 in the United States, driven by environmental and lifestyle factors such as tobacco and alcohol use, dietary habits, and pollution. Major modifiable risk factors include tobacco and alcohol consumption, with a synergistic risk increase when combined. Nonmodifiable risk factors include previous diagnoses of head and neck squamous cell carcinoma (H&N SCC), achalasia, and prior radiotherapy. Prevention strategies must be tailored to specific regional burdens to efficiently allocate medical and financial resources. Gastrointestinal endoscopy is crucial in reducing ESCC burden through early detection and characterization of neoplastic changes, such as high-grade dysplasia. Early diagnosis significantly improves survival rates, while endoscopic resection of noninvasive dysplasia can prevent ESCC onset, reducing treatment burden for advanced disease. Postresection surveillance can detect high-risk metachronous lesions. Despite these benefits, endoscopic prevention faces challenges, including the lack of high-level evidence supporting its efficacy, opportunity costs, the need for specialized training and techniques, and the requirement for advanced technology investments. This Position Statement from the World Endoscopy Organization (WEO) aims to address these challenges, supplying recommendations for the exploitation of endoscopic resources regarding the possible role of screening, quality, and training for the detection, characterization, resection, and surveillance of ESCC.

Updates in the Role of Positron Emission Tomography/Computed Tomography in Radiation Oncology in Gastrointestinal Malignancies

Positron Emission Tomography/Computed Tomography (PET/CT) plays a critical role in managing gastrointestinal (GI) cancers within radiation oncology. It enhances tumor detection, staging, and lymph node involvement assessment, leading to better-targeted radiation treatment. PET/CT also aids in delineating tumor volumes to minimize geographic misses, enabling precise dose escalation to metabolically active regions. Despite its benefits, PET/CT has limitations such as false positives and dependency on complementary imaging. Emerging technologies offer real-time adjustments and personalized treatments, advancing precision medicine in GI radiation oncology. Further research is needed to refine PET/CT integration for improved treatment outcomes and cost-effectiveness.

Advances in Diagnostic, Staging, and Restaging Evaluation of Esophageal and Gastric Cancer

The initial endoscopic and staging evaluation of esophagogastric cancers must be accurate and comprehensive in order to select the optimal therapeutic plan for the patient. Esophageal and gastric cancers (and treatment paradigms) are delineated by their proximity to the cardia (within 2 cm). The most frequent and important symptom that informs the initial staging evaluation is dysphagia, which is associated with at least cT3 or locally advanced disease. Endoscopic ultrasound is often needed if earlier stage disease is suspected, preferably in combination with endoscopic mucosal or submucosal resection or fine-needle aspiration of suspicious lymph nodes to enhance staging accuracy.

18F-Fluorodeoxyglucose Positron Emission Tomography Parameters can Predict Long-Term Outcome Following Trimodality Treatment for Oesophageal Cancer

AIMS

¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸FDG-PET/CT) is routinely used for the pre-treatment staging of oesophageal or gastro-oesophageal junction cancers (EGEJC). The aim of this study was to identify objective ¹⁸FDG-PET/CT-derived parameters that can aid in predicting the patterns of recurrence and prognostication in patients with EGEJC.

PATIENTS AND METHODS

EGEJC patients referred for consideration of preoperative chemoradiation therapy were identified and clinicopathological data were collected. ¹⁸FDG-PET/CT imaging data were reviewed and correlated with treatment outcomes. Maximum standardised uptake value (SUV_max), metabolic tumour volume (MTV) and total lesion glycolysis were assessed and association with recurrence-free survival (RFS), locoregional recurrence-free survival (LR-RFS), oesophageal cancer-specific survival (ECSS) and overall survival were evaluated using receiver operating characteristic curves, as well as Cox regression and Kaplan-Meier models.

RESULTS

In total, 191 EGEJC patients completed trimodality treatment and 164 with ¹⁸FDG-PET/CT data were included in this analysis. At the time of analysis, 15 (9.1%), 70 (42.7%) and two (1.2%) patients were noted to have locoregional, distant and both locoregional and distant metastases, respectively. The median RFS was 30 months (9.6-50.4) and the 5-year RFS was 31.1%. The 5-year overall survival and ECSS were both noted to be 34.8%. Pre-treatment MTV₂₅ > 28.5 cm³ (P = 0.029), MTV₄₀ > 12.4 cm³ (P = 0.018) and MTV₅₀ > 10.2 cm³ (P = 0.005) predicted for worse LR-RFS, ECSS and overall survival for MTV definition of voxels ≥25%, 40% and 50% of SUV_max.

CONCLUSION

¹⁸FDG-PET/CT parameters MTV and total lesion glycolysis are useful prognostic tools to predict for LR-RFS, ECSS and overall survival in EGEJC. MTV had the highest accuracy in predicting clinical outcomes. The volume cut-off points we identified for different MTV thresholds predicted outcomes with significant accuracy and may potentially be used for decision making in clinical practice.

Neoadjuvant Strategies for Esophageal Cancer

Neoadjuvant strategies with multimodal therapy including chemotherapy and radiation are the standard of care in locally advanced esophageal cancer. The role of immunotherapy in the perioperative management of esophageal cancer is expanding, and adjuvant nivolumab for patients with residual disease following trimodality therapy has been shown to improve disease-free survival. Applications of checkpoint blockade and positron emission tomography (PET)-directed therapy in the neoadjuvant setting are under investigation in several clinical trials. We review the perioperative management of locally advanced esophageal cancer and recent evidence exploring the role of immune checkpoint inhibitors and PET in guiding neoadjuvant management.

18-Fluoride fluorodeoxyglucose positron emission tomography is impactful in newly diagnosed pancreatic adenocarcinoma

BACKGROUND

Adenocarcinoma of the pancreas has a dismal prognosis. Surgical resection increases survival but is reliant on accurate detection and staging of disease. In overseas studies, ¹⁸ F-FDG positron emission tomography (PET) has been shown to have high diagnostic accuracy and staging utility, but local data remain sparse, in part because the technique has hitherto been unfunded via the Medicare benefits schedule. Although Commonwealth funding for rare tumours (including of the pancreas) has been recently approved to commence in late 2022, the proposed item descriptor wording implies that PET should lead to a significant change in management. Accordingly, the aims of this study are to characterize PET findings in newly diagnosed pancreatic adenocarcinoma using standard parameters, such as the SUV_max , and assess the proportion of cases in which PET altered initial management planning.

METHODS

We analysed the PET findings of these cancers (presence and degree of metabolic activity in the primary lesion, as well as within malignant nodal and metastatic lesions) and compared the pre- and post-PET management plans of the referring specialists.

RESULTS

Of 51 patients we found that (a) increasing SUV_max of the primary lesion correlated with an increase in disease stage (r-value = 0.335; P-value = 0.016), and (b) PET contributed to a significant change in management in 35% of patients.

CONCLUSION

In newly diagnosed pancreatic adenocarcinoma, parameters in PET correlate with disease stage and the overall findings contribute to a significant management change in about 35% of patients.

18F-FDG PET Radiomics as Predictor of Treatment Response in Oesophageal Cancer: A Systematic Review and Meta-Analysis

The best treatment strategy for oesophageal cancer patients achieving a complete clinical response after neoadjuvant chemoradiation is a burning topic. The available diagnostic tools, such as 18F-FDG PET/CT performed routinely, cannot accurately evaluate the presence or absence of the residual tumour. The emerging field of radiomics may encounter the critical challenge of personalised treatment. Radiomics is based on medical image analysis, executed by extracting information from many image features; it has been shown to provide valuable information for predicting treatment responses in oesophageal cancer. This systematic review with a meta-analysis aims to provide current evidence of 18F-FDG PET-based radiomics in predicting response treatments following neoadjuvant chemoradiotherapy in oesophageal cancer. A comprehensive literature review identified 1160 studies, of which five were finally included in the study. Our findings provided that pooled Area Under the Curve (AUC) of the five selected studies was relatively high at 0.821 (95% CI: 0.737–0.904) and not influenced by the sample size of the studies. Radiomics models exhibited a good performance in predicting pathological complete responses (pCRs). This review further strengthens the great potential of 18F-FDG PET-based radiomics to predict pCRs in oesophageal cancer patients who underwent neoadjuvant chemoradiotherapy. Additionally, our review imparts additional support to prospective studies on 18F-FDG PET radiomics for a tailored treatment strategy of oesophageal cancer patients.

SEOM-GEMCAD-TTD Clinical Guideline for the diagnosis and treatment of esophageal cancer (2021)

Esophageal cancer is an aggressive tumor, and is the sixth-leading cause of death from cancer. Incidence is rising in Spain, particularly among men. Two main pathological different subtypes have been described: squamous cell carcinoma and adenocarcinoma. Growing evidence of their epidemiology and molecular differences explains their different response to novel treatments, and they are therefore likely to be treated as two separate entities in the near future. The best results are obtained with a multidisciplinary therapeutic strategy, and the introduction of immunotherapy is a promising new approach that will improve prognosis. In these guidelines, we review the evidence for the different methods of diagnosis and therapeutic strategies that form the basis of our standard of care.

18F-FDG-PET/CT Imaging for Gastrointestinal Malignancies

Gastrointestinal malignancies encompass a variety of primary tumor sites, each with different staging criteria and treatment approaches. In this review we discuss technical aspects of 18F-FDG-PET/CT scanning to optimize information from both the PET and computed tomography components. Specific applications for 18F-FDG-PET/CT are summarized for initial staging and follow-up of the major disease sites, including esophagus, stomach, hepatobiliary system, pancreas, colon, rectum, and anus.

New frontiers in esophageal radiology

Esophageal cancer is the sixth most common cause of cancer related mortality worldwide. Advances in treatment have translated into steadily improving survival rates. Accurate preoperative staging of esophageal cancer is imperative in order to provide an accurate prognosis and direct patients to the most appropriate treatment. Current preoperative staging relies on imaging, most commonly endoscopic ultrasound (EUS), computed tomography (CT) and positron emission tomography (PET). A combination of these modalities should be used in preoperative staging, as each has advantages over another. Magnetic resonance imaging (MRI) has always shown promise in its ability to accurately stage esophageal cancer, though it has not been consistently adopted as a common tool for this purpose. Recent research has demonstrated that MRI can become an integral part of esophageal cancer clinical staging. Advances in MR technology that utilize radial sampling allow for shorter, free breathing techniques without degradation of image quality, resulting in improved capability for T and N staging of esophageal cancer. MRI enhanced with superparamagnetic iron oxide (SPIO) and ultrasmall SPIO (USPIO) nanoparticles has been shown to be useful for the detection of metastatic disease in lymph nodes. This article will review the current evidence in the role that imaging plays in staging esophageal cancer.

Brazilian Group of Gastrointestinal Tumours' consensus guidelines for the management of oesophageal cancer

Oesophageal cancer is among the ten most common types of cancer worldwide. More than 80% of the cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of oesophageal and oesophagogastric junction (OGJ) carcinomas. The Brazilian Group of Gastrointestinal Tumours invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy (including checkpoint inhibitors) and follow-up, which was followed by presentation, discussion and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of oesophageal and OGJ carcinomas in several scenarios and clinical settings.

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.

Contribution of FDG-PET/CT to the management of esophageal cancer patients at multidisciplinary tumor board conferences

Background

A multidisciplinary team approach to the management of esophageal cancer patients leads to better clinical decisions.

Purpose

The contribution of CT, endoscopic and laparoscopic ultrasound to clinical staging and treatment selection by multidisciplinary tumor boards (MTB) in patients with esophageal cancer is well documented. However, there is a paucity of data addressing the role that FDG-PET/CT (PET/CT) plays to inform the clinical decision-making process at MTB conferences. The aim of this study was to assess the impact and contribution of PET/CT to clinical management decisions and to the plan of care for esophageal cancer patients at the MTB conferences held at our institution.

Materials and methods

This IRB approved study included all the cases discussed in the esophageal MTB meetings over a year period. The information contributed by PET/CT to MTB decision making was grouped into four categories. Category I, no additional information provided for clinical management; category II, equivocal and misguiding information; category III, complementary information to other imaging modalities, and category IV, information that directly changed clinical management. The overall impact on management was assessed retrospectively from prospectively discussed clinical histories, imaging, histopathology, and the official minutes of the MTB conferences.

Results

79 patients (61 males and 18 females; median age, 61 years, range, 33–86) with esophageal cancer (53 adenocarcinomas and 26 squamous cell carcinomas) were included. The contribution of PET/CT-derived information was as follows: category I in 50 patients (63%); category II in 3 patients (4%); category III in 8 patients (10%), and category IV information in 18 patients (23%). Forty-five patients (57%) had systemic disease, and in 5 (11%) of these, metastatic disease was only detected by PET/CT. In addition, PET/CT detected previously unknown recurrence in 4 (9%) of 43 patients. In summary, PET/CT provided clinically useful information to guide management in 26 of 79 esophageal cancer patients (33%) discussed at the MTB.

Conclusion

The study showed that PET/CT provided additional information and changed clinical management in 1 out of 3 (33%) esophageal cancer cases discussed at MTB conferences. These results support the inclusion whenever available, of FDG-PET/CT imaging information to augment and improve the patient management decision process in MTB conferences.

[F18] FDG-PET/CT for manual or semiautomated GTV delineation of the primary tumor for radiation therapy planning in patients with esophageal cancer: is it useful?

Background

Target volume definition of the primary tumor in esophageal cancer is usually based on computed tomography (CT) supported by endoscopy and/or endoscopic ultrasound and can be difficult given the low soft-tissue contrast of CT resulting in large interobserver variability. We evaluated the value of a dedicated planning [F18] FDG-Positron emission tomography/computer tomography (PET/CT) for harmonization of gross tumor volume (GTV) delineation and the feasibility of semiautomated structures for planning purposes in a large cohort.

Methods

Patients receiving a dedicated planning [F18] FDG-PET/CT (06/2011–03/2016) were included. GTV was delineated on CT and on PET/CT (GTV_CT and GTV_PET/CT, respectively) by three independent radiation oncologists. Interobserver variability was evaluated by comparison of mean GTV and mean tumor lengths, and via Sørensen–Dice coefficients (DSC) for spatial overlap. Semiautomated volumes were constructed based on PET/CT using fixed standardized uptake values (SUV) thresholds (SUV30, 35, and 40) or background- and metabolically corrected PERCIST-TLG and Schaefer algorithms, and compared to manually delineated volumes.

Results

45 cases were evaluated. Mean GTV_CT and GTV_PET/CT were 59.2/58.0 ml, 65.4/64.1 ml, and 60.4/59.2 ml for observers A–C. No significant difference between CT- and PET/CT-based delineation was found comparing the mean volumes or lengths. Mean Dice coefficients on CT and PET/CT were 0.79/0.77, 0.81/0.78, and 0.8/0.78 for observer pairs AB, AC, and BC, respectively, with no significant differences. Mean GTV volumes delineated semiautomatically with SUV30/SUV35/SUV40/Schaefer’s and PERCIST-TLG threshold were 69.1/23.9/18.8/18.6 and 70.9 ml. The best concordance of a semiautomatically delineated structure with the manually delineated GTV_CT/GTV_PET/CT was observed for PERCIST-TLG.

Conclusion

We were not able to show that the integration of PET/CT for GTV delineation of the primary tumor resulted in reduced interobserver variability. The PERCIST-TLG algorithm seemed most promising compared to other thresholds for further evaluation of semiautomated delineation of esophageal cancer.

Novel 5-point 18-FDG-PET/CT visual scoring system for assessing treatment response in patients with oesophageal or gastro-oesophageal junction carcinoma

INTRODUCTION

The purpose of this study was to investigate the prognostic utility and reproducibility of a qualitative 5-point 18-fluorodeoxyglucose (FDG)-PET primary visual score (PVS) in patients with oesophageal and gastro-oesophageal junction (GOJ) cancer.

METHODS

This was a retrospective review of patients with histologically proven oesophageal or GOJ cancer who received curative intent therapy. Clinical, pathological and imaging data were extracted from electronic medical records. Patients were required to have pre-treatment and post-treatment FDG-PET scans, that were evaluated with a 5-point primary visual score (prePVS, postPVS). The changes in PVS (ΔPVS) were correlated with progression-free survival and overall survival. Interobserver variability was assessed using Cohen's Kappa intraclass correlation and agreement.

RESULTS

Sixty-seven patients were retrospectively identified. Two (3%), 36 (54%) and 29 (43%) of the patients had stage I, II and III disease respectively. Twenty-five (37%) patients had squamous cell carcinoma. Thirty-seven (55%) patients proceeded onto surgical resection. postPVS was associated with both PFS (P = 0.013) and OS (P = 0.0002). ΔPVS predicted for PFS (P = 0.002) and OS (P = 0.0003). When thresholds of response were considered, agreement was 80.6% (K = 0.78) and 74.6% (K = 0.69) for postPVS and ΔPVS respectively.

CONCLUSION

Qualitative assessment of oesophageal and GOJ cancers utilising FDG-PET is reproducible and may be able to prognosticate outcomes in patients undergoing treatment. Prospective validation is required.

Role of precision imaging in esophageal cancer

Esophageal cancer is a major cause of morbidity and mortality worldwide. Recent advancements in the management of esophageal cancer have allowed for earlier detection, improved ability to monitor progression, and superior treatment options. These innovations allow treatment teams to formulate more customized management plans and have led to an increase in patient survival rates. For example, in order for the most effective management plan to be constructed, accurate staging must be performed to determine tumor resectability. This article reviews the multimodality imaging approach involved in making a diagnosis, staging, evaluating treatment response and detecting recurrence in esophageal cancer.

Prognostic value of 18F-FDG PET/MR imaging biomarkers in oesophageal squamous cell carcinoma

PURPOSE

To correlate the clinical stage and prognosis of oesophageal squamous cell carcinoma (SCC) using the imaging biomarkers from integrated positron emission tomography (PET)/magnetic resonance imaging (MRI).

METHODS

In total, 54 consecutive patients with oesophageal SCC who receive PET/MRI scan were recruited before treatment. The imaging biomarkers used were the mean and minimal apparent diffusion coefficients (ADC_mean and ADC_min), standardized uptake value (SUV), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) of tumours. The correlation between each imaging biomarker and survival was investigated using the Cox proportional hazards model.

RESULTS

ADC_mean was negatively correlated with SUV_max (r = -0.414, P =  0.025). ADC_min was negatively correlated with SUV_max (r = -0.423, P =  0.001) and SUV_peak (r = -0.402, P =  0.003), and was significantly lower in M1 than in M0 tumours (829.6 vs. 1069.8, P = 0.005). MTV was significantly higher in T3 + (P <  0.001), N1 + (P = 0.014) and TNM stage III + (P <  0.001) tumours. TLG was significantly higher in T3 + (P <  0.001), N1 + (P <  0.001), M1 (P =  0.045) and TNM stage III + (P <  0.001) tumours. The MTV/ADC_min ratio exhibited the highest area under the receiver operating characteristic curve (AUROC) for predicting M1 and advanced TNM stage tumours. Multivariate analysis for progression-free survival (PFS) and overall survival (OS) showed that a larger MTV/ADC_min was associated with a shorter PFS and OS (P = 0.024 and 0.046, respectively).

CONCLUSION

The imaging biomarkers in integrated PET/MRI may predict clinical stage and survival in patients with oesophageal SCC.

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 (%ΔSUVmax) 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 %ΔSUVmax 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. %ΔSUVmax 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.

Imaging biomarkers for the treatment of esophageal cancer

Esophageal cancer is known as one of the malignant cancers with poor prognosis. To improve the outcome, combined multimodality treatment is attempted. On the other hand, advances in genomics and other "omic" technologies are paving way to the patient-oriented treatment called "personalized" or "precision" medicine. Recent advancements of imaging techniques such as functional imaging make it possible to use imaging features as biomarker for diagnosis, treatment response, and prognosis in cancer treatment. In this review, we will discuss how we can use imaging derived tumor features as biomarker for the treatment of esophageal cancer.

Can the Efficacy of [18F]FDG-PET/CT in Clinical Oncology Be Enhanced by Screening Biomolecular Profiles?

Positron Emission Tomography (PET) is a functional imaging modality widely used in clinical oncology. Over the years the sensitivity and specificity of PET has improved with the advent of specific radiotracers, increased technical accuracy of PET scanners and incremental experience of Radiologists. However, significant limitations exist—most notably false positives and false negatives. Additionally, the accuracy of PET varies between cancer types and in some cancers, is no longer considered a standard imaging modality. This review considers the relative influence of macroscopic tumour features such as size and morphology on 2-Deoxy-2-[¹⁸F]fluoroglucose ([¹⁸F]FDG) uptake by tumours which, though well described in the literature, lacks a comprehensive assessment of biomolecular features which may influence [¹⁸F]FDG uptake. The review aims to discuss the potential influence of individual molecular markers of glucose transport, glycolysis, hypoxia and angiogenesis in addition to the relationships between these key cellular processes and their influence on [¹⁸F]FDG uptake. Finally, the potential role for biomolecular profiling of individual tumours to predict positivity on PET imaging is discussed to enhance accuracy and clinical utility.

Clinical significance of SUVmax on preoperative 18F-fluorodeoxyglucose positron emission tomography in patients who underwent R0-esophagectomy for esophageal cancer

The standardized uptake value (SUV) is a marker of tumor glucose metabolism, detected using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and may reflect tumor aggressiveness. The purpose of this study was to evaluate the clinical significance of maximum SUV (SUVmax) of primary esophageal cancer (EC) lesions. A total of 86 patients with EC who underwent pre-treatment FDG-PET and R0-resection were included in our study. The mean patient age was 65 years, and 87% were men. Histologically, cancers included squamous cell carcinomas, adenocarcinomas, and other tumors in 72, 3, and 11 patients, respectively. Preoperative chemotherapy with or without radiotherapy was performed in 4 and 37 patients, respectively. Measured patient outcomes included the correlation between the SUVmax of the primary EC lesion and clinicopathological factors in patients who did not undergo preoperative treatment (n = 45), and the investigation of relapse-free survival (RFS) according to SUVmax and the relationship between SUVmax and recurrence sites in all patients (n=86). The mean SUVmax was 8.9 ± 4.6, and SUVmax values significantly correlated with tumor invasion depth and stage. The 5-year RFS for the enrolled patients was 57%, and the RFS of patients with SUVmax < 7.0 was better than that of patients with SUVmax ≥ 7.0, with a marginal difference (p = 0.0892). Lymph node recurrences were significantly more common in patients with SUVmax ≥ 7.0, compared to patients with SUVmax < 7.0. Therefore, the SUVmax value of the primary EC lesion before preoperative treatment may be predictive of RFS and lymph node recurrence.

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.

Does Metastatic Lymph Node SUVmax Predict Survival in Patients with Esophageal Cancer?

Objective:

We aimed to investigate the SUVmax of primary tumor and metastatic lymph node in predicting survival in patients with esophageal cancer.

Methods:

We retrospectively analyzed patients with esophageal cancer between 2009 and 2011 who had FDG positron-emission tomography (PET)/computed tomography (CT). All patients were followed-up to 2013. Clinical staging, SUVmax of primary tumor and metastatic lymph node were evaluated.

Results:

One hundred seven patients were included in the study. All patients were followed-up between 2 and 49 months. The mean SUVmax of primary tumor and metastatic lymph node were 19.3±8.8 and 10.4±9.1, respectively. Metastatic lymph node SUVmax had an effect in predicting survival whereas primary tumor SUVmax did not have an effect (p=0.014 and p=0.262, respectively). Multivariate Cox regression analysis showed that clinical stage of the disease was the only independent factor predicting survival (p=0.001).

Conclusion:

Among patients with esophageal cancer, the value of primary tumor SUVmax did not have an effect on survival. Clinical stage assessed with FDG PET/CT imaging was found to predict survival in esophageal carcinoma. Additionally, lymph node SUVmax was identified as a new parameter in predicting survival in the present study.

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.

Individualized Radiation Dose Escalation Based on the Decrease in Tumor FDG Uptake and Normal Tissue Constraints Improve Survival in Patients With Esophageal Carcinoma

BACKGROUND

To determine whether individualized radiation dose escalation after planned chemoradiation based on the decrease in tumor and normal tissue constraints can improve survival in patients with esophageal carcinoma.

METHODS

From August 2005 to December 2010, 112 patients with squamous esophageal carcinoma were treated with radical concurrent chemoradiation. Patients received positron emission tomography-computer tomography scan twice, before radiation and after radiation dose of 50.4 Gy. All patients were noncomplete metabolic response groups according to the Response Evaluation Criteria in solid tumors. Only 52 patients with noncomplete metabolic response received individualized dose escalation based on tumor and normal tissue constraints. Survival and treatment failure were observed and analyzed using SPSS (13.0).

RESULTS

The rate of complete metabolic response for patients with noncomplete metabolic response after dose escalation reached 17.3% (9 of 52). The 2-year overall survival rates for patients with noncomplete metabolic response in the conventional and dose-escalation groups were 20.5% and 42.8%, respectively( P = .001). The 2-year local control rates for patients were 35.7% and 76.2%, respectively ( P = .002). When patients were classified into partial metabolic response and no metabolic response, 2-year overall survival rates for patients with partial metabolic response were significantly different in conventional and dose-escalation groups (33.8% vs 78.4%; P = .000). The 2-year overall survival rates for patients with no metabolic response in two groups (8.6% vs 15.1%) did not significantly differ ( P = .917).

CONCLUSION

Individualized radiation dose escalation has the potential to improve survival in patients with esophageal carcinoma according to increased rate of complete metabolic response. However, further trials are needed to confirm this and to identify patients who may benefit from dose escalation.

Inter-institutional survival heterogeneity in chemoradiation therapy for esophageal cancer: exploratory analysis of the JCOG0303 study

It is important to examine variation in the treatment effects of patients with esophageal cancer in order to generalize treatment outcomes. We aimed to investigate the range of prognostic differences among hospitals in the treatment of locally advanced esophageal cancer. The JCOG0303 study compared the efficacy of radiotherapy plus low-dose cisplatin and 5-fluorouracil with that of high-dose cisplatin and 5-fluorouracil for unresectable esophageal cancer. Of 32 institutions participating in the JCOG0303 study, the 18 institutions that enrolled three or more patients were included in this study. We predicted the 1-year survival in each institution by using a mixed-effect model. We found that the predicted 1-year survival in the 18 institutions with three or more patients was a median of 60.9%, with a range of 60.9-60.9%. This study is the first to investigated heterogeneity of survival in patients who received definitive chemoradiotherapy for locally advanced esophageal squamous cell carcinoma.

Esophageal Carcinoma: Current Concepts in the Role of Imaging in Staging and Management

Over the past few decades, the survival of esophageal cancer patients has improved owing to early detection and advances in multimodality treatment strategies. Imaging plays an important role in every step in the management of esophageal cancer, including diagnosis, staging, assessment of treatment response, and post-treatment surveillance. In this article, we provide a comprehensive review of the role of imaging in these various time points of esophageal cancer management.

Prognostic value of baseline FDG uptake on PET-CT in esophageal carcinoma

AIM: To evaluate the influence of baseline maximum standardized uptake value (SUV_max) on survival in a cohort of patients, undergoing positron emission tomography-computed tomography (PET-CT) scan for esophageal carcinoma.

METHODS: The pre-treatment SUV_max numeric reading was determined in patients with confirmed esophageal or junctional cancer having PET-CT scan during the time period 1^st January 2007 until 31^st July 2012. A minimum follow up of 12 mo was required. Patients were subdivided into quartiles according to SUV_max value and the influence of SUV_max on survival was assessed using univariate and multivariate analysis. The following pre-treatment factors were investigated: patient characteristics, tumor characteristics and planned treatment.

RESULTS: The study population was 271 patients (191 male) with esophageal or junctional carcinoma. The median age was 65 years (range 40-85) and histologic subtype was adenocarcinoma in 197 patients and squamous carcinoma in 74 patients. The treatment intent was radical in 182 and palliative in 89 patients. SUV_max was linked to histologic subtype (P = 0.008), tumor site (P = 0.01) and Union for International Cancer Control (UICC) stage (P < 0.001). On univariate analysis, prognosis was significantly associated with SUV_max (P = 0.001), T-stage (P < 0.001) and UICC stage (P < 0.001). On multivariate analysis, only T-stage and UICC stage remained significant.

CONCLUSION: Pretreatment SUV_max was not a useful marker in isolation for determining prognosis of patients with esophageal carcinoma.

Intended versus inferred care after PET performed for initial staging in the National Oncologic PET Registry

The National Oncologic PET Registry (NOPR) collected data on intended management before and after PET in cancer patients. We have previously reported that PET was associated with a change in intended management of about one third of patients and was consistent across cancer types. It is uncertain if intended management plans reflect the actual care these patients received. One approach to assess actual care received is using administrative claims to categorize the type and timing of clinical services.

METHODS

NOPR data from 2006 to 2008 were linked to Medicare claims for consenting patients aged 65 y or older undergoing initial-staging PET scanning for bladder, ovarian, pancreatic, small cell lung, or stomach cancers. We determined the 60-d agreement between claims-inferred care and NOPR treatment plans.

RESULTS

Patients (n = 4,661) were assessed, and 30%-52% had metastatic disease. Planned treatments were about two-thirds monotherapy, of which 46% was systemic therapy only, and one-third combinations. Claims paid by 60 d confirmed the NOPR plan of any systemic therapy, radiotherapy, or surgery in 79.3%, 64.7%, and 63.6%, respectively. Single-mode plans were much more often confirmed: systemic therapy in more than 85% of patients with ovarian, pancreatic, and small cell lung cancers and surgery in more than 73% of those with bladder, pancreatic, and stomach cancers. Intended combination treatments had claims for both in only 28% of patients receiving surgery-based combinations and in 55% receiving chemoradiotherapy. About 90% of patients with NOPR-planned systemic therapy had evaluation or management claims from a medical oncologist. An age of less than 75 y was associated more often with confirmation of chemotherapy, less often for radiotherapy but not with confirmation of surgery. Performance status or comorbidity did not explain confirmation rates within action categories, but confirmation rates were higher if the referrer specialized in the planned treatment.

CONCLUSION

Claims confirmations of NOPR intent for initial staging were widely variable but were higher than previously reported for restaging PET, suggesting that measuring change in intended management is a reasonable method for assessing the impact diagnostic tests have on actual care.

Utility of baseline positron emission tomography with computed tomography for predicting endoscopic resectability and survival outcomes in patients with early esophageal adenocarcinoma

BACKGROUND AND AIMS

Positron emission tomography with computed tomography (PET/CT) has been used to detect metastasis in the diagnosis of esophageal adenocarcinoma (EAC). However, the utility of PET/CT to assess primary tumor for endoscopic resectability and prognosis in early EAC remains unclear. We conducted a retrospective study to determine the association of PET/CT findings with histopathological tumor invasion depth and survival outcomes.

METHODS

EAC patients who underwent PET/CT followed by endoscopic mucosal resection (EMR) were included. Pathology on EMR and survival outcomes from a prospectively maintained database was retrieved. Two radiologists independently reviewed the PET/CT using the following parameters: detection of malignancy, fluorodeoxyglucose (FDG) uptake intensity, FDG focality, FDG eccentricity, esophageal thickness, maximal standard uptake value (SUVmax), and SUVmax ratio (lesion/liver).

RESULTS

There were 72 eligible patients: 42 (58.3%) had T1a lesions, and 30 (41.7%) had ≥ T1b. Only SUVmax ratio was associated with tumor invasion depth (odds ratio=2.77, 95% confidence interval 1.26-7.73, P=0.0075). Using a cut-off of 1.48, the sensitivity and specificity of SUVmax ratio for identification of T1a lesions were 43.3% and 80.9%, respectively. Adjusting the SUVmax ratio to 2.14, 16.7% (5/30) of ≥ T1b patients were identified without any false-positive cases. Multivariate analysis showed SUVmax ratio, Charlson comorbidity index, and esophagectomy were independent predictors for survival.

CONCLUSIONS

SUVmax ratio (lesion/liver) is more accurate in predicting endoscopic resectability and mortality for EAC than other PET/CT parameters and appears promising as a useful adjunct to the current diagnostic work-up.

Positron emission tomography imaging for gastroesophageal junction tumors

Positron emission tomography (PET) is now widely used in the initial evaluation of esophageal and gastroesophageal junction tumors. It can detect otherwise occult metastases, affecting staging and treatment in a significant proportion of patients. The intensity of PET uptake before treatment has been correlated with outcomes, but it remains uncertain whether PET is an independent prognostic factor for survival. An emerging application for PET is the assessment of response to induction chemotherapy or chemoradiotherapy. In particular, PET has the ability to discriminate treatment responders from nonresponders early in the course of induction chemotherapy. This can form the basis for further treatment decisions, such as a change in chemotherapy or the addition of concurrent radiotherapy, and this approach is now being tested in prospective trials. PET after concurrent chemoradiotherapy may also provide information regarding the utility of surgical resection. PET data can affect radiotherapy target definition, which may lead to improved tumor coverage in cases where the true extent of disease is not accurately reflected by computed tomography or endoscopic imaging.

Intended versus inferred management after PET for cancer restaging: analysis of Medicare claims linked to a coverage with evidence development registry

BACKGROUND

The National Oncologic PET Registry (NOPR) ascertained changes in the intended management of cancer patients using questionnaire data obtained before and after positron emission tomography (PET) under Medicare's coverage with evidence development policy.

OBJECTIVE

To assess the concordance between intended care plans and care received as ascertained through administrative claims data.

RESEARCH DESIGN

Analysis of linked data of NOPR participants from 2006 to 2008 and their corresponding Medicare claims.

SUBJECTS

Consenting patients aged older than 65 years having their first PET for restaging of bladder, kidney, ovarian, pancreas, prostate, small cell lung, or stomach cancer.

MEASURES

: Agreement (positive predictive values and κ) between NOPR post-PET intended management plans for treatment (systemic therapy, radiotherapy, surgery, or combinations), biopsy, or watching as compared to claims-inferred care 30 days after PET.

RESULTS

A total of 8460 patients with linked data were assessed. A total of 43.5% had metastatic disease and 45.3% had treatment planned (predominantly systemic therapy only), 11.1% biopsy and 43.5% watching. Claims-confirmed intended plans (positive predictive value) for single-mode systemic therapy in 62.0%, radiation in 66.0%, surgery in 45.6%, and biopsy in 55.7%. A total of 25.7% of patients with a plan of watching had treatment claims. By cancer type, κ ranged for systemic therapy only from 0.17 to 0.40 and for watching from 0.21 to 0.41. Agreement rates varied by cancer types but were minimally associated with patient age, performance status, comorbidity, or stage.

CONCLUSIONS

Among elderly cancer patients undergoing PET for restaging, there was moderate concordance between their physicians' planned management and claims-inferred actions within a narrow time window. When higher accuracy levels are required in future coverage with evidence development studies, alternative designs will be needed.

(18)F-FDG PET-detected synchronous primary neoplasms in the staging of esophageal cancer: incidence, cost, and impact on management

PURPOSE

F-Fluorodeoxyglucose positron emission tomography (F-FDG PET) imaging is increasingly the standard of care in the staging of esophageal cancer. Synchronous neoplasms may be identified, and this study evaluated the prevalence of such tumors and their impact on management.

METHODS

Five hundred ninety-one (73.6%) of 803 consecutive patients with biopsy-proven esophageal cancer underwent staging F-FDG PET or PET/CT scans. F-FDG-avid lesions were considered synchronous primary neoplasms if occurring at locations atypical for metastases from the known primary, a marked discordance in the F-FDG avidity from that of the primary tumor, and if there was no prior detection on conventional imaging. Additional investigations as appropriate were undertaken, and histopathological verification was obtained where possible to validate the suspected synchronous neoplasm.

RESULTS

A synchronous neoplasm was suspected in 55 (9.3%) of 591 patients, predominantly at sites in the colon (26) and head and neck (21). Additional investigations in 43 cases revealed malignant neoplasms in 8 (18.6%), premalignant in 9 (20.9%), and benign lesions in 26 (60.5%) cases. The management plan was altered in 8 patients, 1.4% overall. The total cost of added tests was $27,482.57 (&OV0556;21,024) with the decision to treat the esophageal cancer deferred by a mean of 10.7 days.

CONCLUSION

F-FDG uptake concerning for synchronous neoplasms is evident in approximately 1 in 10 cases, and of these a minority will represent a malignant neoplasm that significantly impacts on treatment. The overall added costs per patient are relatively modest and the treatment delay within acceptable limits of clinical practice.

Metabolic tumor volume assessed by 18F-FDG PET/CT for the prediction of outcome in patients with multiple myeloma

(18)F-FDG PET/CT allows the direct measurement of metabolic tumor burden in a variety of different malignancies. The aim of this study was to assess whether metabolic tumor volume (MTV) determined by (18)F-FDG PET/CT could be used in the prediction of progression-free and overall survival in multiple myeloma patients.

METHODS

Forty-seven patients (18 women, 29 men; mean age ± SD, 63 ± 11 y) with stage IIIA disease who had undergone whole-body (18)F-FDG PET/CT were retrospectively evaluated. Images underwent a 3-dimensional region-of-interest analysis including all focal lesions with a maximum standardized uptake value > 2.5. The MTV of each lesion was calculated using an automated contouring program based on the standardized uptake value and developed with a threshold of 40% of the maximum standardized uptake value. The total MTV of each patient was defined as the sum of metabolic volume of all focal lesions. Patients were treated and then subjected to a mean follow-up period of 24 mo.

RESULTS

In the 47 patients studied, MTV range was 1.3-316.3 mL, with a median of 23.7 mL. A direct, significant correlation was found between MTV and the percentage of diffuse infiltration of bone marrow by plasma cells (r = 0.46, P = 0.006), whereas hemoglobin levels were inversely correlated with MTV (r = -0.56, P = 0.0001). At follow-up, patients who developed progressive disease (n = 18) showed a significantly higher MTV (74.7 ± 19.3 vs. 29.8 ± 5.1 mL, P = 0.009) than patients without progressive disease (n = 29). Furthermore, patients who died of myeloma (n = 9) had a significantly higher MTV (123.2 ± 30.6 vs. 28.9 ± 4.2 mL, P = 0.0001) than survivors (n = 38). No differences in age, plasma cell infiltration, M protein, albumin, β2-microglobulin, performance status, International Staging System score, and presence or absence of a bone marrow transplant were found between groups. The MTV cutoff level was determined by receiver-operating-characteristic curve analysis, and the best discriminative value found for predicting progression-free and overall survival was 42.2 and 77.6 mL, respectively. By Kaplan-Meier analysis and log-rank testing, progression-free and overall survival at follow-up were significantly better in patients showing an MTV lower than the cutoff than in those having an MTV higher than the cutoff (χ(2) = 3.9, P = 0.04, and χ(2) = 56.3, P < 0.0001, respectively).

CONCLUSION

The direct measurement of tumor burden obtained by calculating MTV on (18)F-FDG PET/CT images may be used in the prediction of progression-free and overall survival in myeloma patients.

Should positron emission tomography/computed tomography be the first rather than the last test performed in the assessment of cancer?

Cancer is a major cause of illness and death in Western society and is associated with a heavy concomitant economic burden. Although use of imaging comprises only a small proportion of the fiscal impact of cancer, its use has been increasing over recent decades, causing concern amongst funders of health care and efforts to constrain the use of new imaging tests with a relatively high unit cost. In clinical practice, positron emission tomography/computed tomography (PET/CT) is generally performed when less expensive tests have left some uncertainty regarding appropriate management. In this setting, its utility relates to provision of incremental diagnostic information. However, given that superior diagnostic information can positively affect patient management, wherein the majority of costs reside, it may be both more efficient and cost effective to go directly to the most accurate investigation in certain situations. For PET/CT, the ability to provide more accurate assessment of metastatic status than is available from conventional diagnostic paradigms provides a rationale for its independent rather than incremental use in patients presenting with either a high likelihood of malignancy or proven malignancy of a locally advanced nature and an accordingly high risk of metastatic disease. A randomized trial design is described that could be used to test this hypothesis.

Prognostic ability of 18F-FDG PET/CT in the assessment of colorectal liver metastases

Modern multidisciplinary therapy for colorectal liver metastases (CRLM) is associated with significant morbidity and must be adapted to the patient's relative risk. The tools currently available to risk-stratify patients are limited. This study assessed the prognostic utility of metabolic measurements derived from(18)F-FDG PET compared with previously proposed prognostic scoring systems.

METHODS

Preoperative (18)F-FDG PET/CT studies from a series of 30 patients who underwent liver resection for CRLM after neoadjuvant chemotherapy were evaluated. Quantitative (18)F-FDG PET analysis calculated the maximum and mean standardized uptake value, metabolic tumor volume (MTV), and tumor glycolytic volume (TGV) as measures of the metabolic activity of tumors. The predictive value of these parameters was compared with that of 4 prognostic scores developed by Fong, Iwatsuki, Nordlinger, and Rees.

RESULTS

High MTV and TGV in patients before metastasectomy were significantly associated with poorer overall survival (MTV: P = 0.001; TGV: P = 0.004) and recurrence-free survival (MTV: P = 0.001, TGV; P = 0.002). Maximum and mean standardized uptake value did not show any significant predictive ability. Of the prognostic scores, prediction of outcome was most accurate using the Basingstoke index (area under the curve, 0.898).

CONCLUSION

Assessment of metabolic tumor burden with volumetric (18)F-FDG PET parameters appears to be a valuable adjunct in determining the biology of CRLM before surgical resection and may enable better risk stratification of patients.

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

The aim of this study is to evaluate the incremental staging information, management impact, and prognostic stratification of PET/CT in the primary staging of esophageal cancer in a cohort of patients with mature survival data.

METHODS

Between July 2002 and June 2005, 139 consecutive patients with newly diagnosed esophageal cancer underwent conventional staging investigations (CSI), followed by PET/CT. Disease stage was classified according to the American Joint Committee on Cancer staging system (6th edition) and grouped as stage I-IIA, stage IIB-III, and stage IV reflecting broad groupings that determine therapeutic choice. Validation of results was performed when PET/CT and CSI stage groups were discordant and in those patients where PET/CT changed management. Management impact was determined by comparing prospectively recorded pre-PET/CT management plans with post-PET/CT management plans. Survival after follow-up of at least 5 y in patients was analyzed using the Kaplan-Meier product limit method and the Cox proportional hazards regression model.

RESULTS

PET/CT changed the stage group in 56 of 139 (40%) patients and changed management in 47 of 139 (34%) patients. In 22 patients, therapy was changed from curative to palliative and in 3 from palliative to curative; in 11, treatment modality was changed without a change in treatment intent, and in 11 the delivery of therapy or diagnostic procedure was changed. Of the 47 patients with management change, imaging results could be validated in 31 patients, and PET/CT correctly changed management in 26 (84%) of these. Of the remaining 5 patients, CSI stage was also incorrect in 4 and correct in 1. Median survival was 23 mo. PET/CT stages I-IIA, IIB-III, and IV had a 5-y survival of 40%, 38%, and 6%, respectively. Post-PET/CT stage group and treatment intent were both strongly associated with survival (P < 0.001).

CONCLUSION

PET/CT provides incremental staging information compared with CSI, changes management in one third of patients, and has powerful prognostic stratification in the primary staging of esophageal cancer.

Accuracy of PET-CT in predicting survival in patients with esophageal cancer

BACKGROUND

Positron emission tomography (PET) is an integral part of tumor staging for patients with esophageal cancer. Recent studies suggest a role for PET scan in predicting survival in these patients, but this relationship is unclear in the setting of neoadjuvant therapy. We examined pretreatment maximum standard uptake value (SUV(max)) of the primary tumor in patients treated with and without neoadjuvant therapy.

METHODS

All patients undergoing esophagectomy with a preoperative PET scan over a nine-year period (2001-2010) were identified from a prospectively maintained database. Positron emission tomography data were obtained from computers housing the original PET scans. Overall survival was correlated with SUV(max) of the primary tumor.

RESULTS

A total of 191 patients were identified, and 103 patients met inclusion criteria. Eighty-two had an adenocarcinoma (80%), and 21 (20%) had a squamous cell carcinoma. Fifty-seven (55%) patients received neoadjuvant therapy. In the surgery alone group, a SUV(max) of > 5.0 in the primary tumor was associated with poor prognosis [Hazard Ratio (HR) 0.32; p = 0.007], but this factor did not retain its significance on multivariate analysis (HR 0.65; p = 0.43). Pretreatment SUV(max) in patients who underwent neoadjuvant therapy was not significant in predicting overall survival (p = 0.10).

CONCLUSIONS

This study does not support the use of SUV(max) on pretreatment PET scans as a prognostic tool for patients with esophageal cancer, especially in those who have received neoadjuvant therapy. Lymph node status is a more accurate predictor of outcome, and efforts to improve pretreatment staging should focus on this factor.

Prognostic Value of 18F-FDG Standard Uptake Value by Integrated PET/CT in the Staging of Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a rare and aggressive tumor with generally disappointing results in terms of survival, however, there are occasional long-term survivors probably due to the biologic characteristics of the disease. Standard uptake value (SUV) of [18F] Fluorodeoxyglucose (FDG) evaluated by photon emission tomography (PET) is now widely accepted as an indicator of biologic behavior in several malignancies. The aim of this study was to verify whether SUVmax and SUVmean are inversely associated with the prognosis of patients with MPM and whether there was a correlation between grading/disease stage and SUV value. Patients with histologically proven MPM underwent integrated PET and computed tomography (CT) scanning. Patients fasted and received 5.18 MBq of FDG per kilogram of body weight. Based on the maximum Chi-Square method, a SUVmax of 4.21 (range: 2.30–14.74) and a SUVmean of 2.78 (range: 1.80–7.00) were used to classify patients as having a good or poor prognosis, respectively. From January 2004 to March 2010, 27 patients were analyzed: median age was 65 years (range: 54–77) and histologic MPM subtypes were epithelioid (23 patients) and biphasic (4 patients). At a median follow-up of 23 months (range: 1–52), there was no difference in median survival for either high or low SUVmax [26 months (range: 11-not reached) vs.19 months (range: 12-not reached); p = 0.811] or for high or low SUVmean [26 months (range: 8-not reached) vs.19 months (range: 11-not reached); p = 0.831]. High SUVmax (p = 0.018) was statistically correlated with high-stage disease. There was only a trend towards statistical significance between high-grade disease and high SUVmean (p = 0.083); no such trend was found between advanced stages and SUVmax (p = 0.268). We observed a significant correlation only between high SUVmax and high-grade disease. No other relationships between SUVmax and SUVmean with biologic and clinical parameters were found. This is probably due to the patient characteristics and to the non-routine use of 18F-FDG PET/CT to stage rare tumors such as MPM.

Impact of partial-volume effect correction on the predictive and prognostic value of baseline 18F-FDG PET images in esophageal cancer

The objective of this study was to investigate the clinical impact of partial-volume effect (PVE) correction on the predictive and prognostic value of metabolically active tumor volume (MATV) measurements on (18)F-FDG PET baseline scans for therapy response and overall survival in esophageal cancer patients.

METHODS

Fifty patients with esophageal cancer treated with concomitant radiochemotherapy between 2004 and 2008 were retrospectively considered. PET baseline scans were corrected for PVE with iterative deconvolution incorporating wavelet denoising. MATV delineation on both original and corrected images was performed using the automatic fuzzy locally adaptive Bayesian methodology. Several parameters were extracted considering the original and corrected images: maximum and peak standardized uptake value (SUV), mean SUV, MATV, and total lesion glycolysis (TLG) (TLG = MATV × mean SUV). The predictive value of each parameter with or without correction was investigated using Kruskal-Wallis tests, and the prognostic value was determined with Kaplan-Meier curves.

RESULTS

Whereas PVE correction had a significant quantitative impact on the absolute values of the investigated parameters, their clinical value within the clinical context of interest was not significantly modified-a result that was observed for both overall survival and response to therapy. The hierarchy between parameters was the same before and after correction. SUV measurements (maximum, peak, and mean) had nonsignificant (P > 0.05) predictive or prognostic value, whereas functional tumor-related measurements (MATV and TLG) were significant (P < 0.002) predictors of response and independent prognostic factors.

CONCLUSION

PVE correction does not improve the predictive and prognostic value of baseline PET image-derived parameters in esophageal cancer patients.

F-18 FDG PET/CT contributes to more accurate detection of lymph nodal metastasis from actively proliferating esophageal squamous cell carcinoma

PURPOSE

Evaluating the status of disease progression is critical for planning a therapeutic strategy for esophageal cancer. In this regard, F-18 fluorodeoxyglucose-labeled positron emission tomography (PET) is one of the most useful diagnostic modalities. However, there is room to improve its diagnostic performance, such as distinguishing lymph nodal metastases from false positives. In this study, we examined the diagnostic accuracy of fluorodeoxyglucose PET accompanied by computed tomography imaging (PET/CT) to detect regional lymph nodal metastasis from esophageal squamous cell carcinoma (ESCC).

METHODS

A total of 102 patients diagnosed as ESCC were subjected to this study. These patients had a preoperative PET/CT examination to evaluate the existence of metastasis. The values of maximum standardized uptake value (SUVmax) in primary tumors and in metastasized lymph nodes were measured to analyze their relationship with various clinicopathologic characteristics including the status of tumor cell proliferation, which was assessed by immunohistochemistry for Ki-67.

RESULTS

The SUVmax of the primary tumor was positively correlated with tumor size and vessel invasion, and was positively related with the SUVmax of lymph nodal metastasis, especially in cases of poorly differentiated ESCC. The SUVmax of metastasized lymph nodes was higher in larger-sized metastasized lymph nodes, whereas the Ki-labeling index of lymph nodal metastasis was positively related with the SUVmax per unit area (SUVmax/mm). The diagnostic accuracy of PET/CT (87.3%) was higher than that of conventional CT scans (78.4%).

CONCLUSIONS

The improved diagnostic accuracy of PET/CT can be explained by its ability to detect actively progressive metastasis at an early phase regardless of size.