The Efficacy of FDG-PET for the Management of Esophageal Cancer: Review Article

Role of Textural Analysis of Pretreatment 18F Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Response Prediction in Esophageal Carcinoma Patients

Introduction

Positron emission tomography/computed tomography (PET/CT) is routinely used for staging, response assessment, and surveillance in esophageal carcinoma patients. The aim of this study was to investigate whether textural features of pretreatment 18F-fluorodeoxyglucose (18F-FDG) PET/CT images can contribute to prognosis prediction in carcinoma oesophagus patients.

Materials and Methods

This is a retrospective study of 30 diagnosed carcinoma esophagus patients. These patients underwent pretreatment 18F-FDG PET/CT for staging. The images were processed in a commercially available textural analysis software. Region of interest was drawn over primary tumor with a 40% threshold and was processed further to derive 92 textural and radiomic parameters. These parameters were then compared between progression group and nonprogression group. The original dataset was subject separately to receiver operating curve analysis. Receiver operating characteristic (ROC) curves were used to identify the cutoff values for textural features with a P < 0.05 for statistical significance. Feature selection was done with principal component analysis. The selected features of each evaluator were subject to 4 machine-learning algorithms. The highest area under the curve (AUC) values was selected for 10 features.

Results

A retrospective study of 30 primary carcinoma esophagus patients was done. Patients were followed up after chemo-radiotherapy and they underwent follow-up PET/CT. On the basis of their response, patients were divided into progression group and nonprogression group. Among them, 15 patients showed disease progression and 15 patients were in the nonprogression group. Ten textural analysis parameters turned out to be significant in the prediction of disease progression. Cutoff values were calculated for these parameters according to the ROC curves, GLZLM_long zone emphasis (Gray Level Zone Length Matrix)_long zone emphasis (44.9), GLZLM_low gray level zone emphasis (0.006), GLZLM_short zone low gray level emphasis (0.0032), GLZLM_long zone low gray level emphasis (0.185), GLRLM_long run emphasis (Gray Level Run Length Matrix) (1.31), GLRLM_low gray level run emphasis (0.0058), GLRLM_short run low gray level emphasis (0.005496), GLRLM_long run low gray level emphasis (0.00727), NGLDM_Busyness (Neighborhood Gray Level Difference Matrix) (0.75), and gray level co-occurrence matrix_homogeneity (0.37). Feature selection by principal components analysis and feature classification by the K-nearest neighbor machine-learning model using independent training and test samples yielded the overall highest AUC.

Conclusions

Textural analysis parameters could provide prognostic information in carcinoma esophagus patients. Larger multicenter studies are needed for better clinical prognostication of these parameters.

Prognostic Assessment of Interim F18-Fluorodeoxyglucose Positron Emission Tomography in Esophageal Cancer Treated With Chemoradiation With or Without Surgery

Purpose

This study aimed to evaluate if the F18-fluorodeoxyglucose positron emission tomography (F18-FDG PET) response after two weeks of chemoradiation for locoregionally advanced esophageal cancer (staged Tumor (T) 3 and/or Nodes (N)+ Metastases (M) 0) was linked to the pathologic response for patients undergoing surgery, to disease-free survival (DFS) or overall survival (OS).

Materials and Methods

Between March 2006 and September 2017, 40 patients were prospectively enrolled in our study, gave written consent, and had PET scans performed before treatment and after two weeks of chemoradiation. One patient did not undergo his two-week PET without informing study coordinators and was excluded from analyses.

Results

The median age at diagnosis was 62 years. Seventy-two percent of patients had N+ disease. Median OS for the entire group was 24 months. Five-year overall survival was 17%. Survival curves for patients with no PET response, minor PET response, or good PET response overlapped and were not statistically different. For the 25 patients who underwent surgery, the positive predictive value (PPV) of the PET response relative to the pathologic response was 75% and the negative predictive value (NPV) was 62%. In study patients, the crude recurrence rate was 68% and there was no correlation between PET response and DFS.

Conclusion

In our study, interim PET response after two weeks of chemoradiation for locoregionally advanced esophageal cancer was not predictive of outcome or pathologic response. Based on our data and current literature, interim PET should not be used to alter treatment (whether to escalate neo-adjuvant treatment or omit surgery).

Role of Imaging in Esophageal Cancer Management in 2020: Update for Radiologists

OBJECTIVE. The purpose of this article is to discuss the role of imaging in the management of esophageal cancer. CONCLUSION. A multimodality-based approach to imaging is essential in clinical practice to achieve the best possible outcome for patients with esophageal cancer. Radiologists must be aware of the strengths and limitations of different imaging modalities in various clinical settings. The role of a radiologist is to combine information from anatomic and functional imaging, assess metastatic disease and changes in the primary tumor during treatment, and identify anatomic complications after treatment.

Role of 18F-FDG PET/CT in restaging of esophageal cancer after curative-intent surgical resection

OBJECTIVE

The aim of the study was to evaluate diagnostic performance of FDG PET-CT in suspected recurrence of carcinoma esophagus after curative-intent surgical resection and impact of FDG PET-CT on intended management.

MATERIAL AND METHODS

This was retrospective study of patients with clinical or radiological suspicion of recurrent esophageal carcinoma who were referred for PET-CT from January 2006 to December 2017. Diagnostic performance of PET-CT was evaluated for disease recurrence and its impact on management decisions. PET-CT findings were confirmed with tissue diagnosis. When tissue diagnosis was not available clinical and radiological follow-up was used as reference standard.

RESULTS

Relevant clinical data were available in 68 patients which were considered for analysis. In 91% (62/68) patients FDG PET-CT findings were suggestive of disease recurrence. Histopathological confirmation was available in 43 patients, whereas in remaining patients recurrence was confirmed by radiological and clinical follow-up. Forty percent (28/68) patients were detected with distant metastases. Sensitivity, specificity, positive and negative predictive values of FDG PET-CT was found to be 98.4, 80, 98 and 80% with accuracy of 97%. Change in management was observed in 41% (28/68) of patients from salvage radiotherapy/surgery to palliative chemotherapy/best supportive care based on evidence of distant metastases seen on FDG PET-CT.

CONCLUSION

FDG PET-CT is highly sensitive in detection of recurrent disease in esophageal cancer patients after surgical resection. It can detect distant metastases in high proportion of patients thus changing the intent of management from radical salvage to palliative chemotherapy/best supportive care.

Prognostic Value of Functional Parameters of 18F-FDG-PET Images in Patients with Primary Renal/Adrenal Lymphoma

Objectives

The aim of this study is to explore the textural features that may identify the morphological changes in the lymphoma region and predict the prognosis of patients with primary renal lymphoma (PRL) and primary adrenal lymphoma (PAL).

Methods

This retrospective study comprised nineteen non-Hodgkin's lymphoma (NHL) patients undergoing ¹⁸F-FDG-PET/CT at West China Hospital from December 2013 to May 2017. ¹⁸F-FDG-PET images were reviewed independently by two board certificated radiologists of nuclear medicine, and the texture features were extracted from LifeX packages. The prognostic value of PET FDG-uptake parameters, patients' baseline characteristics, and textural parameters were analyzed using Kaplan–Meier analysis. Cox regression analysis was used to identify the independent prognostic factors among the imaging and clinical features.

Results

The overall survival of included patients was 18.84 ± 13.40 (mean ± SD) months. Univariate Cox analyses found that the tumor stage, GLCM (gray-level co-occurrence matrix) entropy, GLZLM_GLNU (gray-level nonuniformity), and GLZLM_ZLNU (zone length nonuniformity), values were significant predictors for OS. Among them, GLRLM_RLNU ≥216.6 demonstrated association with worse OS at multivariate analysis (HR 9.016, 95% CI 1.041–78.112, p=0.046).

Conclusions

The texture analysis of ¹⁸F-FDG-PET images could potentially serve as a noninvasive strategy to predict the overall survival of patients with PRL and PAL.

Clinical Significance of 18F-Fluorodeoxyglucose-Positron Emission Tomography-Positive Lymph Nodes to Outcomes of Trimodal Therapy for Esophageal Squamous Cell Carcinoma

BACKGROUND

The clinical significance of lymph node (LN) status determined by preoperative ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET) has not been investigated in patients with locally advanced esophageal squamous cell carcinoma (ESCC) treated with neoadjuvant chemoradiotherapy (NCRT) followed by surgery (trimodal therapy).

METHODS

This study reviewed 132 consecutive patients with ESCC who had been preoperatively evaluated using FDG-PET before and after NCRT to analyze associations among LN status according to PET findings, pathologic LN metastasis, and prognosis of ESCC after trimodal therapy.

RESULTS

Lymph nodes that were PET-positive both before and after NCRT comprised significant predictive markers of pathologic LN metastasis in station-by-station analyses (sensitivity, specificity, and accuracy respectively 41.7%, 95.0%, and 92.7% before, and 12.0%, 99.4%, and 95.6% after NCRT; both p < 0.0001). The numbers of LNs evaluated using PET before and after NCRT were significantly associated with those of pathologic metastatic LNs. Uni- and multivariable analyses selected LN status determined by PET before NCRT as a significant independent predictor of both recurrence-free [LN-negative vs LN-positive: hazard ratio (HR) 1.90; 95% confidence interval (CI) 1.02-3.23; p = 0.045] and overall survival (HR 2.62; 95% CI 1.29-5.30; p = 0.01).

CONCLUSIONS

The status of LN determined by preoperative FDG-PET is significantly associated with pathologic LN status and the prognosis of ESCC with trimodal therapy. Thus, FDG-PET is a useful diagnostic tool for preoperative prediction of pathologic LN metastasis and survival among patients with ESCC.

The Optimal Chinese Herbal Injections for Use With Radiotherapy to Treat Esophageal Cancer: A Systematic Review and Bayesian Network Meta-Analysis

Ethnopharmacological relevance: Esophageal cancer is one of the most common human cancers, and its incidence is highly endemic in China. The combination of Chinese herbal injections (CHIs) and radiotherapy should be informed by the best available evidence.

Aim of the study: To update and expand on previous work in order to compare and rank the efficacy and safety of CHIs in combination with radiotherapy to treat esophageal cancer.

Materials and Methods: We searched several electronic databases to identify randomized controlled trials (RCTs) regarding CHIs to treat esophageal cancer from their inception to March 15, 2017. In a network meta-analysis (NMA), the bias of the included trials was assessed by two individuals independently in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. Outcomes such as the clinical effectiveness rate, performance status, adverse reactions (ADRs), and survival rate were evaluated. We performed a random-effects NMA to obtain estimates of efficacy and safety outcomes, and we present these estimates as odds ratios (ORs) and corresponding 95% confidence intervals (CIs) calculated via Stata 13.1 and WinBUGS 1.4 software. Furthermore, the surface under cumulative the ranking curve (SUCRA) was used to rank the efficacy and safety of different CHIs in relation to each outcome.

Results: Of 685 identified trials, 55 were eligible for inclusion in the study. These 55 trials included 12 CHIs and 4,114 participants. The cluster analysis results suggested that Compound kushen injection therapy is the optimal CHI treatment for patients with esophageal cancer in terms of improving the clinical effectiveness rate and performance status. Huachansu and Kangai injection are superior in improving 1-year and 2-year survival rates. Lentinan injection may be considered a favorable choice for reliving ADRs, and Compound kushen injection may provide treatment benefits by reducing both gastrointestinal reaction and radiation esophagitis.

Conclusions: The current clinical evidence indicated that Compound kushen injection combined with radiotherapy is the most preferable and beneficial option for patients with esophageal cancer in terms of efficacy and safety. However, the results of our study should be interpreted with caution given the limitations of the sample size and the methodological quality of the included trials.

Ectopic Papillary Thyroid Carcinoma Mimicking Esophageal Cancer in FDG PET: A Case Report

Ectopic papillary thyroid carcinoma (PTC) usually occurs along the cervical midline and was barely reported in FDG PET studies. We present a rare case of ectopic PTC within the esophagus with focal FDG activity on FDG PET in a 43-year-old woman who was previously diagnosed as having esophageal cancer based on the endoscopy and PET findings. Surgical pathology revealed the presence of PTC lesion within the muscular layer of the esophagus. Combining this with the negative imaging and laboratory results suggesting a normal thyroid gland led to a diagnosis of primary ectopic PTC.

Minimally Invasive Salvage Operations for Esophageal Cancer after Definitive Chemoradiotherapy

BACKGROUND/AIMS

Because salvage surgery after definitive chemoradiotherapy for esophageal cancer is associated with high postoperative mortality and morbidity, minimally invasive methods are desirable. We analyzed the validity of minimally invasive salvage operations (MISO).

METHODS

Twenty-five patients underwent salvage operation between 2010 and 2016 in our institution, 10 having undergone right transthoracic salvage esophagectomy (TTSE group), 6 transhiatal salvage esophagectomy (THSE), 6 salvage lymphadenectomy (SLA), and 3 salvage endoscopic submucosal dissection (SESD). Patients who had undergone THSE, SLA, or SESD were categorized as the MISO group. Short- and long-term outcomes were assessed.

RESULTS

The mean duration of surgery was significantly shorter in the SLA groups than in the TTSE group (p = 0.0248). Blood loss was significantly less in the SLA than the TTSE group (p = 0.0340). Intensive care unit stay was shorter in the THSE than the TTSE group (p = 0.0412). There was no significant difference in postoperative mortality between the MISO and THSE groups. Postoperative hospital stay was significantly shorter in the SLA than the TTSE group (p = 0.0061). Patients' survivals did not differ significantly between the MISO and TTSE groups (p = 0.752). Multivariate analysis revealed that residual disease (R0; HR 4.872, 95% CI 1.387-17.110, p = 0.013) was the only independent factor influencing overall survival.

CONCLUSION

MISO is preferable because short-term outcomes are better and long-term outcomes do not differ from those of TTSE.

Towards precision medicine: from quantitative imaging to radiomics

Radiology (imaging) and imaging-guided interventions, which provide multi-parametric morphologic and functional information, are playing an increasingly significant role in precision medicine. Radiologists are trained to understand the imaging phenotypes, transcribe those observations (phenotypes) to correlate with underlying diseases and to characterize the images. However, in order to understand and characterize the molecular phenotype (to obtain genomic information) of solid heterogeneous tumours, the advanced sequencing of those tissues using biopsy is required. Thus, radiologists image the tissues from various views and angles in order to have the complete image phenotypes, thereby acquiring a huge amount of data. Deriving meaningful details from all these radiological data becomes challenging and raises the big data issues. Therefore, interest in the application of radiomics has been growing in recent years as it has the potential to provide significant interpretive and predictive information for decision support. Radiomics is a combination of conventional computer-aided diagnosis, deep learning methods, and human skills, and thus can be used for quantitative characterization of tumour phenotypes. This paper discusses the overview of radiomics workflow, the results of various radiomics-based studies conducted using various radiological images such as computed tomography (CT), magnetic resonance imaging (MRI), and positron-emission tomography (PET), the challenges we are facing, and the potential contribution of radiomics towards precision medicine.

Clinicopathological Features of Cervical Esophageal Cancer: Retrospective Analysis of 63 Consecutive Patients Who Underwent Surgical Resection

OBJECTIVE

The objectives of this retrospective study were to elucidate the clinicopathological features and recent surgical results of cervical esophageal cancer.

SUMMARY BACKGROUND DATA

Cervical esophageal cancer has been reported to have a dismal prognosis. Accurate knowledge of the clinical characteristics of cervical esophageal cancer is warranted to establish appropriate therapeutic strategies.

METHODS

The clinicopathological features and treatment results of 63 consecutive patients with cervical esophageal cancer (Ce group) who underwent surgical resection from 1980 to 2013 were analyzed and compared with 977 patients with thoracic or abdominal esophageal cancer (T/A group) who underwent surgical resection during that time.

RESULTS

Among the patients who received curative resection, the 5-year overall and disease-specific survival rates of the Ce patients were significantly better than those of the T/A patients (overall: 77.3% vs 46.5%, respectively, P = 0.0067; disease-specific: 81.9% vs 55.8%, respectively, P = 0.0135). Although total pharyngo-laryngo-esophagectomy procedures were less frequently performed in the recent period, the rate of curative surgical procedures was markedly higher in the recent period (2000-1013) than that in the early period (1980-1999) (44.4% vs 88.9%, P = 0.0001). The 5-year overall survival rate in the recent period (71.5%) was significantly better than that in the early period (40.7%, P = 0.0342).

CONCLUSIONS

Curative resection for cervical esophageal cancer contributes to favorable outcomes compared with other esophageal cancers. Recent surgical results for cervical esophageal cancer have improved, and include an increased rate of curative resection and decreased rate of extensive surgery.

Texture analysis of 18F-FDG PET/CT to predict tumour response and prognosis of patients with esophageal cancer treated by chemoradiotherapy

PURPOSE

This retrospective study was done to examine whether the heterogeneity in primary tumour F-18-fluorodeoxyglucose (¹⁸F-FDG) distribution can predict tumour response and prognosis of patients with esophageal cancer treated by chemoradiotherapy (CRT).

METHODS

The enrolled 52 patients with esophageal cancer underwent ¹⁸F-FDG-PET/CT studies before CRT. SUVmax, SUVmean, metabolic tumour volume (MTV, SUV ≥ 2.5), total lesion glycolysis (TLG) and six heterogeneity parameters assessed by texture analysis were obtained. Patients were classified as responders or non-responders according to Response Evaluation Criteria in Solid Tumors. Progression-free survival (PFS) and overall survival (OS) were calculated by the Kaplan-Meier method. Prognostic significance was assessed by Cox proportional hazards analysis.

RESULTS

Thirty four non-responders showed significantly higher MTV (p = 0.006), TLG (p = 0.007), intensity variability (IV; p = 0.003) and size-zone variability (SZV; p = 0.004) than 18 responders. The positive and negative predictive values for non-responders were 77 % and 69 % in MTV, 76 % and 100 % in TLG, 78 % and 67 % in IV and 78 % and 82 % in SZV, respectively. Although PFS and OS were significantly shorter in patients with high MTV (PFS, p = 0.018; OS, p = 0.014), TLG (PFS, p = 0.009; OS, p = 0.025), IV (PFS, p = 0.013; OS, p = 0.007) and SZV (PFS, p = 0.010; OS, p = 0.007) at univariate analysis, none of them was an independent factor, while lymph node status, stage and tumour response status were independent factors at multivariate analysis.

CONCLUSION

Texture features IV and SZV, and volumetric parameters MTV and TLG can predict tumour response, but all of them have limited value in prediction of prognosis of patients with esophageal cancer treated by CRT.

Staging of adenocarcinoma of the gastroesophageal junction

BACKGROUND

Clinical staging of adenocarcinoma of the gastroesophageal junction (GEJ) determines the curative treatment regimen containing either neoadjuvant chemotherapy or chemoradiotherapy followed by either gastrectomy or esophagectomy. The value of current diagnostic tools is a matter of debate.

METHODS

A prospective database (2003-2013) was used to identify 266 consecutive patients with adenocarcinoma of the GEJ in order to evaluate the accuracy of endoscopic ultrasound (EUS) and computed tomography (CT) regarding tumor localization according to Siewert, nodal status and its consequences on treatment strategy.

RESULTS

Overall accuracy in determining tumor localization was 73% for endoscopy/EUS and 61% for CT (p = 0.018). With endoscopy/EUS, the accuracy was 97%, 66% and 75% respectively for type I, II and III. With CT this was respectively 69%, 57% and 80%. The overall accuracy for determining N-status (N0/N+) per patient was 75% for EUS and 71% for CT. Accuracy for determining a positive nodal station in patients without neoadjuvant therapy was 77% for EUS and 71% for CT (p = 0.001). Accuracy for detecting positive upper mediastinal nodes was 80-92%, whereas for peritumoral and abdominal nodes this was 50-80% in both EUS and CT. In 8/266 patients (3%) the type of surgery changed due to intraoperative findings. A radical resection was performed in 233 patients (88%).

CONCLUSIONS

Despite the suboptimal accuracy of determining tumor localization with EUS and CT, in only a small number of patients an intraoperative change of surgical treatment was needed. EUS is superior to CT in determining nodal status and tumor localization in GEJ tumors.

Patterns of nodal metastases on 18F-FDG PET/CT in patients with esophageal squamous cell carcinoma are useful to guide treatment planning of radiotherapy

BACKGROUND AND PURPOSES

The aim of the study was to examine the patterns of lymph node metastases from esophageal squamous cell carcinoma (ESCC) and compare the laterality of lymphatic metastasis in cervical, supraclavicular, and paratracheal areas using F-FDG PET/CT.

PATIENTS AND METHODS

The data of 75 patients who underwent F-FDG PET/CT for staging of ESCC between January 2011 and March 2012 were reviewed. Fourteen groups of lymph nodes from the neck to abdomen were defined. Lateralization of the upper thoracic lymph nodes was defined in reference to the midline of the trachea. Frequencies of positive lymph nodes were used to determine the pattern of lymphatic spread and compare the lateralization of metastases in the cervical and upper thoracic regions.

RESULTS

The right paratracheal region was the most frequent site of metastasis among all patients. Left paratracheal and paragastric nodes were more frequent in upper and lower third ESCC, respectively. Upward and downward lymphatic spread was equal in mid third ESCC. In all patients, there was a trend toward more frequent lymph node metastasis on the right side than the left side for the supraclavicular and paratracheal regions. Further stratified analysis with tumor location found that right paratracheal node metastasis was significantly associated with mid third ESCC (P = 0.03). Remote nodal metastasis was found in 10.5% of patients with upper third ESCC and 13% of patients with lower third ESCC, respectively. Remote nodal metastasis was associated with higher SUV of the primary tumor (P = 0.02) and worse survival (P = 0.03). Receiver operating characteristic analysis showed a cutoff SUV of 14.8 for predicting remote lymph node metastases.

CONCLUSIONS

PET/CT provides important information before radiotherapy planning. Mid and lower third ESCC tends to metastasize to the right paratracheal/supraclavicular lymph nodes. Remote nodal metastases on PET/CT correlated with higher primary tumor SUV and worse survival.

PET/CT imaging correlates with treatment outcome in patients with multidrug-resistant tuberculosis

Definitive clinical trials of new chemotherapies for treating tuberculosis (TB) require following subjects until at least 6 months after treatment discontinuation to assess for durable cure, making these trials expensive and lengthy. Surrogate endpoints relating to treatment failure and relapse are currently limited to sputum microbiology, which has limited sensitivity and specificity. We prospectively assessed radiographic changes using 2-deoxy-2-[(18)F]-fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) at 2 and 6 months (CT only) in a cohort of subjects with multidrug-resistant TB, who were treated with second-line TB therapy for 2 years and then followed for an additional 6 months. CT scans were read semiquantitatively by radiologists and were computationally evaluated using custom software to provide volumetric assessment of TB-associated abnormalities. CT scans at 6 months (but not 2 months) assessed by radiologist readers were predictive of outcomes, and changes in computed abnormal volumes were predictive of drug response at both time points. Quantitative changes in FDG uptake 2 months after starting treatment were associated with long-term outcomes. In this cohort, some radiologic markers were more sensitive than conventional sputum microbiology in distinguishing successful from unsuccessful treatment. These results support the potential of imaging scans as possible surrogate endpoints in clinical trials of new TB drug regimens. Larger cohorts confirming these results are needed.

Diagnostic value of ¹⁸F-FDG PET/CT for lymph node metastasis of esophageal squamous cell carcinoma

PURPOSE

This study investigated the diagnostic accuracy of hybrid positron-emission tomography/computed tomography (PET/CT) for lymph node (LN) metastasis of esophageal cancer. We also investigated the correlation between the size of metastatic nests and the detection by PET/CT.

METHODS

Two hundred and fifty-eight patients with esophageal squamous cell carcinoma who underwent esophagectomy with two- or three-field radical lymphadenectomy were analyzed retrospectively. We compared the diagnosis of preoperative PET/CT to the postoperative histopathological examination by each anatomical field (n = 1,231) in all 258 patients. The metastatic LNs resected from PET/CT positive fields were classified as belonging to the PET/CT-N-positive group (n = 229) and those from negative fields as belonging to the PET/CT-N-negative group (n = 352). The cross-sectional areas of metastatic nests were measured in each metastatic LN.

RESULTS

Of the 1,231 fields, 275 (22 %) were positive for metastasis, including 581 LNs from 408 regional LN stations. The sensitivity and specificity of PET/CT examined by each anatomical field were 25.8 and 97.8 %, respectively. The median area of metastatic nests was 17.7 mm2 in the PET/CT-N-positive group, and 7.7 mm2 in the PET/CT-N-negative group (p < 0.001).

CONCLUSIONS

A significant correlation was suggested between the nest size and detection by PET/CT. Because of its low sensitivity, PET/CT alone is insufficient to determine the surgical procedures, especially when considering reduction surgery.

Clinical significance of surgical resection for the recurrence of esophageal cancer after radical esophagectomy

BACKGROUND

This study aimed to clarify the clinical significance of surgical resection for recurrent lesions after esophagectomy for esophageal cancer.

METHODS

Recurrence was detected in 113 of 365 consecutive patients who underwent surgical resection for esophageal cancer, and some treatment was performed for recurrence in 100 of the 113 patients. The treatments were classified into two groups: chemotherapy and/or radiation with surgery (surgery group, n = 14) and chemotherapy and/or radiation without surgery (no surgery group, n = 86). The outcomes were retrospectively analyzed.

RESULTS

Of the 14 patients in the surgery group, 3 underwent repeated resection. Thus, a total of 22 resections were performed for these patients. The resected organs were the lymph nodes in nine patients, the lungs in six patients, local recurrence in two patients, subcutaneous recurrence in two patients, the liver in one patient, the brain in one patient, and the parotid gland in one patient. Among the 22 recurrent cases, 20 involved solitary lesions or multiple lesions located in a small resectable region. When the two groups were compared, the surgery group showed a more favorable prognosis in terms of both survival after esophagectomy (median survival time, 103.3 vs 23.1 months; p = 0.0060) and survival after initial recurrence (92.1 vs 12.2 months; p = 0.0057).

CONCLUSIONS

Multimodal treatment provides a significant benefit for patients with recurrence after esophagectomy for esophageal cancer. Surgical intervention should be aggressively included in the treatment strategy when the recurrent lesion is solitary or localized.

Recent Trends in PET Image Interpretations Using Volumetric and Texture-based Quantification Methods in Nuclear Oncology

Image quantification studies in positron emission tomography/computed tomography (PET/CT) are of immense importance in the diagnosis and follow-up of variety of cancers. In this review we have described the current image quantification methodologies employed in (18)F-fluorodeoxyglucose ((18)F-FDG) PET in major oncological conditions with particular emphasis on tumor heterogeneity studies. We have described various quantitative parameters being used in PET image analysis. The main contemporary methodology is to measure tumor metabolic activity; however, analysis of other image-related parameters is also increasing. Primarily, we have identified the existing role of tumor heterogeneity studies in major cancers using (18)F-FDG PET. We have also described some newer radiopharmaceuticals other than (18)F-FDG being studied/used in the management of these cancers. Tumor heterogeneity studies are being performed in almost all major oncological conditions using (18)F-FDG PET. The role of these studies is very promising in the management of these conditions.

Concordance of studies for nodal staging is prognostic for worse survival in esophageal cancer

Pretreatment clinical staging in esophageal cancer influences prognosis and treatment strategy. Current staging strategies utilize multiple imaging modalities, and often the results are contradictory. No studies have examined the implications of concordance of computed tomography (CT), positron emission tomography (PET), and endoscopic ultrasound (EUS) when used for the evaluation of nodal disease. The objective of this study was to determine if concordance of CT, PET, or EUS for nodal disease predicts worse overall survival. We reviewed 615 esophageal cancer patients with pretreatment CT, PET, and EUS that underwent esophagectomy for survival outcomes based on concordance of studies for nodal disease. Concordant N+ is defined as two or three studies positive for nodal disease; non-concordant N+ is defined as only one positive study. Node-positive disease by any study predicted shorter survival than node-negative disease (42% vs. 73% 5-year survival; P<0.001). Additionally, non-concordant N+ patients had shorter survival than N- patients (52% vs. 73% 5-year survival; P<0.001). Concordant N+ patients had shorter survival than non-concordant N+ patients (38- vs. 61-month median survival; P=0.017). There were no statistically significant differences in survival based on specific combinations of studies. When PET was disregarded, patients with both CT+ and EUS+ had shorter survival than patients with either CT+ or EUS+ (39- vs. 58-month median survival; P=0.029). Pretreatment CT, PET, or EUS concordance for node-positive disease predicts shorter overall survival in patients that undergo esophagectomy for esophageal cancer. Predicting survival in esophageal cancer should consider the synergistic capabilities of CT, PET, and EUS in evaluating nodal status.