Ability of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography to Predict Outcomes of Neoadjuvant Chemoradiotherapy Followed by Surgical Treatment for Esophageal Squamous Cell Carcinoma

Prediction of Pathologic Complete Response in Esophageal Squamous Cell Carcinoma Using Preoperative Serum Small Ribonucleic Acid Obtained After Neoadjuvant Chemoradiotherapy

BACKGROUND

The authors hypothesized that small ribonucleic acid (sRNA) obtained from blood samples after neoadjuvant therapy from patients treated with neoadjuvant chemoradiation therapy (NACRT) could serve as a novel biomarker for predicting pathologic complete response (pCR).

METHODS

This study included 99 patients treated with esophagectomy after NACRT between March 2010 and October 2021 whose blood samples were collected between the end of NACRT and surgery. Next-generation sequencing (NGS) was used to analyze sRNAs from the blood samples. A predictive model for pCR comprising micro-RNA isoforms (isomiR), transfer RNA (tRNA)-derived sRNAs (tsRNAs), and clinical factors was constructed using cross-validation.

RESULTS

Of the 99 patients, pCR was diagnosed for 30 and non-pCR for 69 of the patients. Among sRNAs, the isomiRs of let-7b and miR-93 and the tsRNA group derived from tRNA-Gly-CCC/GCC were identified as predictive factors. The clinical factors included a decrease in the maximum standardized uptake value (SUVmax) at the primary site, clinical complete response post-NACRT, preoperative biopsy, and post-NACRT carcinoembryonic antigen levels. The combined predictive model for pCR (C-PM) was established using the three sRNAs and four clinical factors. The area under the curve for the C-PM was 0.84, which was a significant factor in the multivariate analysis (odds ratio, 89.41; 95 % confidence interval 8.1-987.5; p < 0.001).

CONCLUSIONS

Pathologic complete response after NACRT can be predicted by a predictive model constructed from preoperative clinical factors obtained via minimally invasive procedures and sRNA identified by NGS. Preoperative pCR prediction may influence treatment decision-making after NACRT.

Maximum standardised uptake value of positron emission tomography as a predictor of oesophageal cancer outcomes

OBJECTIVES

This study aimed to analyse the value of pre-operative 18F-fluorodeoxyglucose positron emission tomography (PET)-computed tomography that can predict tumour pathological complete response, tumour histology grade, overall survival, and recurrence-free survival in patients with locally advanced oesophageal squamous cell carcinoma who underwent neoadjuvant chemoradiotherapy (NCRT) followed by surgery.

METHODS

We retrospectively reviewed the cases of patients with locally advanced oesophageal squamous cell carcinoma undergoing NCRT followed by surgery. Patients who did not undergo PET within 3 months of surgery were excluded. We set a pre-operative PET maximum standardised uptake value (SUVmax) of > 5 as the threshold and classified the patients into two groups. We analysed the tumour response and histology grade, and compared the overall survival and recurrence-free survival between the two groups.

RESULTS

This cohort included 92 patients with oesophageal squamous cell carcinoma who underwent NCRT followed by surgery; 49 patients had a pre-operative PET SUVmax < 5, and 43 patients had a pre-operative PET SUVmax > 5. The patients' pre-operative PET SUVmax correlated with tumour histology, ypT stage, and tumour response. Patients with a pre-operative SUVmax < 5 had better 2-year-overall survival (78% vs. 62%, P < 0.05) and 2-year recurrence-free survival (62% vs. 34%, P < 0.05) than those with a pre-operative SUV > 5.

CONCLUSIONS

Pre-operative SUVmax may be useful to predict tumour response, survival, and recurrence in patients with locally advanced oesophageal squamous cell carcinoma who undergo NCRT followed by surgery.

Association between prognosis and lymph node status using 18F-fluorodeoxyglucose-positron emission tomography in esophageal squamous cell carcinoma treated with esophagectomy post-neoadjuvant chemotherapy

BACKGROUND

There are few reports on the associations between lymph node (LN) status, determined by preoperative 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET), and prognosis in patients with locally advanced esophageal squamous cell carcinoma (ESCC) who underwent esophagectomy post-neoadjuvant chemotherapy (NCT). Additionally, details on the diagnostic performance of LN metastasis determination based on pathological examination versus FDG-PET have not been reported. In this study, we aimed to evaluate the associations among LN status using FDG-PET, LN status based on pathological examination, and prognosis in patients with locally advanced ESCC who underwent esophagectomy post-NCT.

METHODS

We reviewed the data of 124 consecutive patients with ESCC who underwent esophagectomy with R0 resection post-NCT between December 2008 and August 2022 and were evaluated pre- and post-NCT using FDG-PET. The associations among LN status using FDG-PET, LN status based on pathological examination, and prognosis were assessed.

RESULTS

Station-by-station analysis of PET-positive LNs pre- and post-NCT correlated significantly with pathological LN metastases (sensitivity, specificity, and accuracy pre- and post-NCT: 51.6%, 96.0%, and 92.1%; and 28.2%, 99.5%, and 93.1%, respectively; both p < 0.0001). Using univariate and multivariate analyses, LN status determined using PET post-NCT was a significant independent predictor of both recurrence-free survival and overall survival.

CONCLUSION

The LN status assessed using FDG-PET post-NCT was significantly associated with the pathological LN status and prognosis in patients with ESCC who underwent esophagectomy post-NCT. Therefore, FDG-PET is a useful diagnostic tool for preoperatively predicting pathological LN metastasis and survival in these patients and could provide valuable information for selecting individualized treatment strategies.

The role of 18F-FDG PET/CT in predicting the pathological response to neoadjuvant PD-1 blockade in combination with chemotherapy for resectable esophageal squamous cell carcinoma

PURPOSE

Accurate assessment of residual disease of tumor and lymph nodes after neoadjuvant immunochemotherapy is crucial in the active surveillance for patients with pathological complete response (pCR) and the optimal extent of lymphadenectomy for patients with non-pCR. This post hoc analysis aimed to evaluate the performance of ¹⁸F-FDG PET/CT to predict the pathological response to neoadjuvant immunochemotherapy for esophageal squamous cell carcinoma (ESCC).

METHODS

Fifty-eight resectable ESCC patients received two cycles of camrelizumab in combination with chemotherapy and were enrolled in the final analysis. The ¹⁸F-FDG PET/CT scans were acquired at baseline (scan-1) and after immunochemotherapy but prior to surgery (scan-2). Maximum standardized uptake value (SUV_max), mean standardized uptake value (SUV_mean), tumor-to-blood pool SUV_max ratio (SUV_TBR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were evaluated for their association with the pathological response to immunochemotherapy.

RESULTS

Nineteen patients (32.8%, 19/58) had pCR and thirty-nine patients (67.2%, 39/58) had non-pCR after two doses of camrelizumab and chemotherapy. At scan-2, the SUV_max, SUV_mean, SUV_TBR, TLG, and MTV were significantly lower in pCR than in non-pCR patients. Decrease in TLG and MTV between scan-2 and scan-1 of the same patient was significantly higher in the pCR than in the non-pCR group. In the receiver operating characteristic curve analysis, SUV_max, SUV_mean, SUV_TBR, TLG, and MTV in scan-2 showed excellent predictive value for the pCR of primary tumors. Furthermore, SUV_max in scan-2 were higher in positive lymph nodes than in negative ones, suggesting a high negative predictive ability (98.6%) with a cut-off value at 1.4.

CONCLUSION

The parameters of ¹⁸F-FDG PET/CT have the excellent performance for predicting pCR after the combined neoadjuvant immunochemotherapy in resectable ESCC.

TRIAL REGISTRATION

ChiCTR2000028900. Registered on January 6, 2020.

Evaluation of Neoadjuvant Chemoradiotherapy Followed by Surgery for Borderline Resectable Esophageal Squamous Cell Carcinoma

BACKGROUND

It is occasionally difficult to diagnose cT3 or cT4b using imaging examinations for esophageal cancer. The optimal treatment strategy for borderline resectable esophageal squamous cell carcinoma (BR-ESCC) is unclear.

METHODS

We included 131 patients with cT3 ESCC who received neoadjuvant chemoradiotherapy (NCRT) followed by surgery. The patients were classified as having definitive cT3 (D-cT3) or borderline resectable cT3 (BR-cT3), based on presence of undeniable adjacent organ invasion on pretreatment CT. Surgical outcomes and prognoses were compared among patients with D-cT3 and BR-cT3 tumors, and the risk factors for non-R0 resection were assessed.

RESULTS

Ninety and 41 patients were classified as D-cT3 and BR-cT3, respectively. Although BR-cT3 had a significantly higher non-R0 resection rate than D-cT3 (D-cT3 3.7%; BR-cT3 14.6%), BR-cT3 was not correlated with shorter overall survival (OS) (D-cT3 5-year OS, 50.8%; BR-cT3 5-year OS 38.4%; p = 0.234). Conversely, non-R0 resection was significantly associated with poor OS (R0 resection 5-year OS 48.8%; non-R0 resection 5-year OS 22.2%; p = 0.031). Cox regression analysis of OS demonstrated that BR-cT3 was not a prognostic factor. In the analysis of risk factors for non-R0 resection, BR-cT3 (p = 0.027), suspected invasion of the trachea or bronchus (p = 0.046), and high SUVmax of the primary lesion after NCRT (p = 0.002) were risk factors.

CONCLUSIONS

NCRT followed by surgery achieved a relatively high R0 resection rate and an almost equal overall survival rate for BR-cT3 compared with D-cT3 ESCC. Thus, NCRT followed by surgery is an effective treatment strategy for patients with BR-cT3 ESCC.

Trimodality therapy for locally advanced esophageal squamous cell carcinoma: the role of volume-based PET/CT in patient management and prognostication

PURPOSE

To evaluate the role of positron emission tomography/computed tomography (PET/CT) in predicting pathologic complete response (pCR) and identify relevant prognostic factors from clinico-imaging-pathologic features of locally advanced esophageal squamous cell carcinoma (eSCC) patients undergoing trimodality therapy.

METHODS

We evaluated 275 patients with eSCCs of T3-T4aN0M0 and T1-T4aN1-N3M0 who received trimodality therapy. We correlated volume-based PET/CT parameters before and after concurrent chemoradiation therapy with pCR after surgery, clinico-imaging-pathologic features, and patient survival.

RESULTS

pCR occurred in 75 (27.3%) of 275 patients, of whom 61 (80.9%) showed 5-year survival. Pre-total lesion glycolysis (pre-TLG, OR = 0.318, 95% CI 0.169 to 0.600), post-metabolic tumor volume (post-MTV, OR = 0.572, 95% CI 0.327 to 0.999), and % decrease of average standardized uptake value (% SUVavg decrease, OR = 2.976, 95% CI = 1.608 to 5.507) were significant predictors for pCR. Among them, best predictor for pCR was pre-TLG with best cutoff value of 205.67 and with AUC value of 0.591. Performance status (HR = 5.171, 95% CI 1.737 to 15.397), pathologic tumor size (HR = 1.645, 95% CI 1.351 to 2.002), pathologic N status (N1, HR = 1.572, 95% CI 1.010 to 2.446; N2, HR = 3.088, 95% CI 1.845 to 5.166), and post-metabolic tumor volume (HR = 1.506, 95% CI 1.033 to 2.195) were significant predictors of overall survival.

CONCLUSION

Pre-TLG, post-MTV, and % SUVavg decrease are predictive of pCR. Additionally, several clinico-imaging-pathologic factors are significant survival predictors in locally advanced eSCC patients undergoing trimodality therapy.

PET-Uptake Reduction into Lymph Nodes After Neoadjuvant Therapy is Highly Predictive of Prognosis for Patients Who have Thoracic Esophageal Squamous Cell Carcinoma Treated with Chemoradiotherapy Plus Esophagectomy

BACKGROUND

Patients with ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET)-positive lymph nodes before treatment have a poor prognosis after esophagectomy. This study investigated whether FDG uptake into lymph nodes on FDG-PET (PET-N) during the pre- or posttreatment stage is more predictive of survival for thoracic esophageal squamous cell carcinoma (TESCC) patients who received neoadjuvant chemoradiotherapy (NACRT) followed by esophagectomy.

METHODS

Of 129 TESCC patients with clinical lymphatic metastasis who underwent curative-intent esophagectomy after NACRT between 2010 and 2018, 97 who received PET before and after NACRT were enrolled in the study. The study defined lymph nodes with a maximum standardized uptake value (SUV_max) greater than 2.5 on FDG-PET before NACRT as cPET-N(+) and after NACRT as CRT-cPET-N(+). Both the cPET-N(+) and CRT-cPET-N(-) patients were defined as PET-N responders. Survival was analyzed using the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

No significant difference in survival was detected between the cPET-N(+) and cPET-N(-) patients. However, the CRT-cPET-N(-) patients had significantly better 5-year overall survival (OS) and disease-specific survival (DSS) than the CRT-cPET-N (+) patients. The PET-N responders had significantly better 5-year OS and DSS than the PET-N non-responders, and PET-N response was an independent prognostic factor for 5-year DSS.

CONCLUSION

The PET-N response is a highly predictive prognostic marker for TESCC patients who undergo NACRT followed by esophagectomy. The PET-N response may help clinicians to establish a strategy for perioperative treatments that improves survival for patients with lymph node metastasis in TESCC.

Predicting the Local Response of Esophageal Squamous Cell Carcinoma to Neoadjuvant Chemoradiotherapy by Radiomics with a Machine Learning Method Using 18F-FDG PET Images

Background: This study aimed to propose a machine learning model to predict the local response of resectable locally advanced esophageal squamous cell carcinoma (LA-ESCC) treated by neoadjuvant chemoradiotherapy (NCRT) using pretreatment 18-fluorodeoxyglucose positron emission tomography (FDG PET) images. Methods: The local responses of 98 patients were categorized into two groups (complete response and noncomplete response). We performed a radiomics analysis using five segmentations created on FDG PET images, resulting in 4250 features per patient. To construct a machine learning model, we used the least absolute shrinkage and selection operator (LASSO) regression to extract radiomics features optimal for the prediction. Then, a prediction model was constructed by using a neural network classifier. The training model was evaluated with 5-fold cross-validation. Results: By the LASSO analysis of the training data, 22 radiomics features were extracted. In the testing data, the average accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve score of the five prediction models were 89.6%, 92.7%, 89.5%, and 0.95, respectively. Conclusions: The proposed machine learning model using radiomics showed promising predictive accuracy of the local response of LA-ESCC treated by NCRT.

Positron emission tomography complete metabolic response as a favorable prognostic predictor in esophageal cancer following neoadjuvant chemotherapy with docetaxel/cisplatin/5-fluorouracil

BACKGROUND

¹⁸F-fluorodeoxyglucose-positron emission tomography (PET)/computed tomography is useful in diagnosing lymph node and distant metastases of esophageal cancer. However, its value for predicting survival is controversial.

AIM

To evaluate the value of PET complete metabolic response (CMR) as a prognostic predictor for esophageal cancer.

METHODS

Between June 2013 and December 2017, 58 patients with squamous cell esophageal cancer who underwent neoadjuvant chemotherapy (NAC) in Oita University were enrolled in this retrospective cohort study. Tumors were clinically staged using fluorodeoxyglucose-PET/computed tomography before and after NAC. After NAC, maximal standardized uptake value ≤ 2.5 was defined as PET-CMR, and maximal standardized uptake value > 2.5 was defined as non-PET-CMR. We compared short-term outcomes between the PET-CMR group and non-PET-CMR group and evaluated prognostic factors by univariate and multivariate analyses.

RESULTS

The PET-CMR group included 22 patients, and the non-PET-CMR group included 36 patients. There were no significant differences in intraoperative and postoperative complications between the two groups. Five-year relapse-free survival and overall survival in the PET-CMR group were significantly more favorable than those in the non-PET-CMR group (38.6 mo vs 20.8 mo, P = 0.021; 42.8 mo vs 25.1 mo, P = 0.011, respectively). PET-CMR was a significant prognostic factor in terms of relapse-free survival by univariate analysis (hazard ratio: 2.523; 95% confidence interval: 1.034–7.063; P < 0.041). Particularly, PET-computed tomography negative N was an independent prognostic factor of relapse-free survival and overall survival by multivariate analysis.

CONCLUSION

PET-CMR after NAC is considered a favorable prognostic factor for esophageal cancer. Evaluation by PET-computed tomography could be useful in clinical decision making for esophageal cancer.

SUVmax reduction predicts long-term survival in patients of non-pCR both in the tumor and lymph nodes after neoadjuvant chemoradiotherapy in esophageal squamous cell carcinoma

Background

A pathological complete response (pCR) after neoadjuvant chemoradiotherapy (NACRT) ensures long-term survival in esophageal squamous cell carcinoma (ESCC) patients following esophagectomy, but pCR patients are a minority. The aim here was to identify prognostic factors in patients with non-pCR ESCC after NACRT.

Methods

This is a retrospective study. Investigated were 5-year overall survival (OS), disease-specific survival (DSS), and relapse-free survival (RFS) among non-pCR ESCC patients divided into pT0N0, primary site pCR (pT0N+), lymph node pCR (pT+N0), and non-pCR in both the tumor and lymph node (pT+N+) subgroups after NACRT and esophagectomy. Focusing on the SUV_max reduction rate in the primary tumor in 88 patients who underwent FDG-PET before and after NACRT, we used univariate and multivariate Cox proportional hazard models to identify prognostic factors.

Results

Although there were no significant survival differences among non-pCR ESCC patients with pT0N+, pT+N0, or pT+N+, survival rate among pT+N+patients was the poorest. After setting a 60% cutoff for the SUV_max reduction rate in the tumor, RFS curves for non-pCR patients significantly differed between patients above the cutoff and those below it. For pT+N+ patients, the SUV_max reduction rate (<60% vs ≥ 60%) was an independent prognostic factor of OS, DSS, and RFS.

Conclusion

Because ESCC patients with SUV_max reduction rates of <60% in the tumor after NACRT and categorized as pT+N+ after NACRT had significantly poorer prognoses, even after esophagectomy, a change in treatment strategy may be an option to improve survival.

Prediction of the tumor response and survival based on computed tomography in esophageal squamous cell carcinoma after trimodality therapy

PURPOSE

Predicting the response to neoadjuvant chemoradiotherapy (NCRT) and the prognosis of esophageal squamous cell carcinoma (ESCC) is challenging. This study evaluated the potential of a preoperative computed tomography (CT) analysis for predicting the pathological response and survival of patients with ESCC who received trimodality therapy.

METHODS

A total of 119 patients with cT3 or T4 ESCC who underwent surgery following NCRT between 2007 and 2019 were assessed. The CT-based parameters were measured with enhanced CT preoperatively, prior to and during treatment. Associations between these parameters and the pathologic response, as well as the prognosis, were examined.

RESULTS

Pretreatment maximum CT value (p = 0.009), pretreatment mean CT value (p = 0.022), preoperative whole tumor volume (WTV, p = 0.003), preoperative largest cross section (LCS, p = 0.002), ΔLCS (pretreatment to preoperative, p = 0.004), ΔWTV (pretreatment to preoperative, p = 0.012), and Δmean CT value (pretreatment to preoperative, p = 0.012) of the primary lesion were significantly associated with a good pathological response. A Cox-regression analysis of recurrence-free survival (RFS) and overall survival (OS) showed that preoperative LCS was an independent CT-based predictor. RFS and OS were significantly higher at the optimal cut-off value of the preoperative LCS (p = 0.036 and p = 0.016, respectively).

CONCLUSIONS

CT-based parameters are thus considered to be valuable predictors of the tumor response and survival after trimodality therapy for ESCC.

Utility of positron emission-computed tomography for predicting pathological response in resectable oesophageal squamous cell carcinoma after neoadjuvant chemoradiation

OBJECTIVES

For patients with locally advanced oesophageal cancer, improved complete pathological response after neoadjuvant chemoradiation (nCRT) and the detrimental effects on the quality of life related to oesophagectomy have led to the need for a reliable method to select patients who have achieved complete pathological response and do not need surgery. The reliability of 18F-fluorodeoxyglucose positron emission-computed tomography (PET-CT) for predicting the pathological response after nCRT was evaluated.

METHODS

Patients with locally advanced oesophageal cancer who were treated with nCRT and oesophagectomy from July 2010 to February 2017 were analysed. On the post-nCRT PET-CT, a complete metabolic response was defined as all tumourous lesions demonstrating maximum standardized uptake value (SUVmax) ≤2.5. To minimize the effect of radiation-induced oesophagitis, complete metabolic response was also defined as no viable lesion distinguishable from the background with diffuse uptake. The sensitivity, specificity, positive predictive value and negative predictive value were analysed for SUVmax, [X]ΔSUVmax and %ΔSUVmax.

RESULTS

A total of 158 patients with oesophageal squamous cell carcinoma were analysed. The rate of complete pathological response was 27.8%, and that of complete metabolic response was 7.6%. The sensitivity, specificity, positive predictive value and negative predictive value based on SUVmax ≤2.5 and visual normalization were 95%, 14%, 74% and 50%, respectively. Analysis for [X]ΔSUVmax and %ΔSUVmax using the optimal cut-off values determined by the receiver operating characteristic curves did not show an improved predictive efficacy.

CONCLUSIONS

PET-CT is not a reliable tool for predicting pathological response. Patients diagnosed with resectable oesophageal cancer who underwent neoadjuvant therapy should not be exempt from surgery based on PET-CT results.

The value of intravoxel incoherent motion diffusion-weighted imaging in predicting the pathologic response to neoadjuvant chemotherapy in locally advanced esophageal squamous cell carcinoma

OBJECTIVE

To explore the value of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) for the prediction of pathologic response to neoadjuvant chemotherapy (NAC) in locally advanced esophageal squamous cell carcinoma (ESCC).

MATERIAL AND METHODS

Forty patients with locally advanced ESCC who were treated with NAC followed by radical resection were prospectively enrolled from September 2015 to May 2018. MRI and IVIM were performed within 1 week before and 2-3 weeks after NAC, prior to surgery. Parameters including apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudodiffusion coefficient (D^*), and pseudodiffusion fraction (f) before and after NAC were measured. Pathologic response was evaluated according to the AJCC tumor regression grade (TRG) system. The changes in IVIM values before and after therapy in different TRG groups were assessed. Receiver operating characteristic (ROC) curves analysis was used to determine the best cutoff value for predicting the pathologic response to NAC.

RESULTS

Twenty-two patients were identified as TRG 2 (responders), and eighteen as TRG 3 (non-responders) in pathologic evaluation. The ADC, D, and f values increased significantly after NAC. The post-NAC D and ΔD values of responders were significantly higher than those of non-responders. The area under the curve (AUC) was 0.722 for post-NAC D and 0.859 for ΔD in predicting pathologic response. The cutoff values of post-NAC D and ΔD were 1.685 × 10^-3 mm²/s and 0.350 × 10^-3 mm²/s, respectively.

CONCLUSION

IVIM-DWI may be used as an effective functional imaging technique to predict pathologic response to NAC in locally advanced ESCC.

KEY POINTS

• The optimal cutoff values of post-NAC D and ΔD for predicting pathologic response to NAC in locally advanced ESCC were 1.685 × 10^-3 mm²/s and 0.350 × 10^-3 mm²/s, respectively. • Pathologic response to NAC in locally advanced ESCC was favorable in patients with post-NAC D and ΔD values that were higher than the optimal cutoff values. • IVIM-DWI can potentially be used to preoperatively predict pathologic response to NAC in esophageal carcinoma. Accurate quantification of the D value derived from IVIM-DWI may eventually translate into an effective and non-invasive marker to predict therapeutic efficacy.

Distribution of Lymph Node Metastasis in Esophageal Squamous Cell Carcinoma After Trimodal Therapy

BACKGROUND

Although metastatic tumors in lymph nodes (LN) are potentially affected by neoadjuvant chemoradiotherapy (NCRT), the distribution of LN metastases of esophageal squamous cell carcinoma (ESCC) after trimodal therapy has never been sufficiently estimated.

PATIENTS AND METHODS

We evaluated the distribution of LN metastases, relationships between LN metastases and radiation fields, risk factors for LN metastasis, and the influence of LN metastasis on the survival of 184 patients with ESCC who underwent NCRT followed by esophagectomy.

RESULTS

Neoadjuvant chemoradiotherapy resulted in down-staged LN status in 74 (49.3%) patients. Pathological LN metastases were extensive in 177 LN stations in the cervical, mediastinal, and abdominal fields, and 162 (91.5%) metastases were located inside the radiation fields. Multivariate analysis showed that clinical N stage [N0 vs. 1/2/3: hazard ratio (HR), 2.69; 95% confidence interval (CI), 1.22-5.92; p = 0.01] and clinical response of primary tumor (complete vs. noncomplete: HR, 2.93; 95% CI, 1.50-5.69; p = 0.002) were statistically significant for pathological LN metastasis. Recurrence-free and overall survivals were significantly stratified according to the number of pathological LN metastases, associations between clinical and pathological LN metastases, and presence or absence of pathological LN metastases outside radiation field.

CONCLUSIONS

About 50% of patients who were clinically diagnosed with LN metastasis before treatment were downstaged by NCRT, and their prognoses were relatively good. However, LN metastases were extensive at the cervical, mediastinal, and abdominal areas, even within the radiation field. Thus, systematic and adequate lymphadenectomy is required for ESCC treated by NCRT.

Predictions of Pathological Features and Recurrence Based on FDG-PET Findings of Esophageal Squamous Cell Carcinoma after Trimodal Therapy

BACKGROUND

The degree of metabolic activity in tumor cells can be determined by 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET). Associations between FDG uptake by primary tumors of locally advanced esophageal squamous cell carcinoma (ESCC) under trimodal therapy and the pathological features of such tumors have not been fully investigated.

PATIENTS AND METHODS

We evaluated relationships between the maximal standardized uptake (SUVmax) in primary tumors on preoperative PET images and pathological features as well as cancer recurrence in 143 patients with ESCC who underwent neoadjuvant chemoradiotherapy (NCRT) followed by surgery.

RESULTS

The post-SUVmax significantly differed after NCRT for ypT and ypN status, lymphatic invasion (LI), venous invasion (VI), and recurrence. Furthermore, the %ΔSUVmax (rate of decrease between before and after NCRT) for LI, VI, and recurrence significantly differed. Univariate and multivariate analyses selected post-SUVmax and %ΔSUVmax as independent preoperative predictors of recurrence-free survival [hazard ratio (HR) 1.46; 95% confidence interval (CI) 1.24-1.72 and HR 0.97; 95% CI 0.96-0.99, respectively; p < 0.001 for both]. Recurrence-free and overall survival were significantly stratified according to optimal SUVmax cutoffs for predicting recurrence (post- and %ΔSUVmax: 2.8 and 70, respectively).

CONCLUSIONS

The post- and %ΔSUVmax of primary tumors were significantly associated with the pathological features and recurrence of ESCC under trimodal therapy. Therefore, FDG-PET can preoperatively predict the degree of aggressive tumor behavior in ESCC under trimodal therapy.

Accuracy of Detecting Residual Disease After Neoadjuvant Chemoradiotherapy for Esophageal Cancer: A Systematic Review and Meta-analysis

OBJECTIVE

The aim of this study was to perform a meta-analysis on the accuracy of endoscopic biopsies, EUS, and 18F-FDG PET(-CT) for detecting residual disease after neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer.

SUMMARY OF BACKGROUND DATA

After nCRT, one-third of patients have a pathologically complete response in the resection specimen. Before an active surveillance strategy could be offered to these patients, clinically complete responders should be accurately identified.

METHODS

Embase, Medline, Cochrane, and Web-of-Science were searched until February 2018 for studies on accuracy of endoscopic biopsies, EUS, or PET(-CT) for detecting locoregional residual disease after nCRT for squamous cell- or adenocarcinoma. Pooled sensitivities and specificities were calculated using random-effect meta-analyses.

RESULTS

Forty-four studies were included for meta-analyses. For detecting residual disease at the primary tumor site, 12 studies evaluated endoscopic biopsies, 11 qualitative EUS, 14 qualitative PET, 8 quantitative PET using maximum standardized uptake value (SUVmax), and 7 quantitative PET using percentage reduction of SUVmax (%ΔSUVmax). Pooled sensitivities and specificities were 33% and 95% for endoscopic biopsies, 96% and 8% for qualitative EUS, 74% and 52% for qualitative PET, 69% and 72% for PET-SUVmax, and 73% and 63% for PET-%ΔSUVmax. For detecting residual nodal disease, 11 studies evaluated qualitative EUS with a pooled sensitivity and specificity of 68% and 57%, respectively. In subgroup analyses, sensitivity of PET-%ΔSUVmax and EUS for nodal disease was higher in squamous cell carcinoma than adenocarcinoma.

CONCLUSIONS

Current literature suggests insufficient accuracy of endoscopic biopsies, EUS, and 18F-FDG PET(-CT) as single modalities for detecting residual disease after nCRT for esophageal cancer.

Circulating microRNA/isomiRs as novel biomarkers of esophageal squamous cell carcinoma

BACKGROUND

MicroRNA (miR)s are promising diagnostic biomarkers of cancer. Recent next generation sequencer (NGS) studies have found that isoforms of micro RNA (isomiR) circulate in the bloodstream similarly to mature micro RNA (miR). We hypothesized that combination of circulating miR and isomiRs detected by NGS are potentially powerful cancer biomarker. The present study aimed to investigate their application in esophageal cancer.

METHODS

Serum samples from patients with esophageal squamous cell carcinoma (ESCC) and age and sex matched healthy control (HC) individuals were investigated for the expression of miR/isomiRs using NGS. Candidate miR/isomiRs which met the criteria in the 1st group (ESCC = 18 and HC = 12) were validated in the 2nd group (ESCC = 30 and HC = 30). A diagnostic panel was generated using miR/isomiRs that were consistently confirmed in the 1st and 2nd groups. Accuracy of the panel was tested then in the 3rd group (ESCC = 18 and HC = 18). Their use was also investigated in 22 paired samples obtained pre- and post-treatment, and in patients with esophageal adenocarcinoma (EAD) and high-grade dysplasia (HGD).

RESULTS

Twenty-four miR/isomiRs met the criteria for diagnostic biomarker in the 1st and 2nd group. A multiple regression model selected one mature miR (miR-30a-5p) and two isomiRs (isoform of miR-574-3p and miR-205-5p). The index calculated from the diagnostic panel was significantly higher in ESCC patients than in the HCs (13.3±8.9 vs. 3.1±1.3, p<0.001). The area under the receiver operating characteristics (ROC) curves of the panel index was 0.95. Sensitivity and specificity were 93.8%, and 81% in the 1st and 2nd groups, and 88.9% and 72.3% in the 3rd group, respectively. The panel index was significantly lower in patients with EAD (6.2±4.5) and HGD (4.2±1.7) than in those with ESCC and was significantly decreased at post-treatment compared with pre-treatment (6.2±5.6 vs 11.6±11.5, p = 0.03).

CONCLUSION

Our diagnostic panel had high accuracy in the diagnosis of ESCC. MiR/isomiRs detected by NGS could serve as novel biomarkers of ESCC.

Association of the primary tumor's SUVmax with survival after surgery for clinical stage IA esophageal cancer: a single-center retrospective study

BACKGROUND

Compared to other esophageal cancers, clinical stage IA esophageal cancer generally has a good prognosis, although a subgroup of patients has a poor prognosis. Unfortunately, clinical diagnoses of invasion depth or lymph node metastasis are not always accurate, which make it difficult to identify patients with a high risk of postoperative recurrence using the tumor-node-metastasis staging system. Fluorodeoxyglucose-positron emission tomography may help guide the identification of malignant tumors and the evaluation of their malignant grade based on glucose metabolism. We aimed to evaluate the association between pre-operative fluorodeoxyglucose-positron emission tomography findings and the postoperative prognosis of patients with clinical stage IA esophageal cancer.

METHODS

This single-center retrospective study evaluated pre-esophagectomy fluorodeoxyglucose-positron emission tomography findings from 38 patients with clinical stage IA esophageal cancer. Receiver operating characteristic curve analysis was performed to evaluate the prognostic significance of the primary tumor having low and high SUVmax values (cut-off: 3.56).

RESULTS

Overall survival (log-rank p = 0.034) and progression-free survival (log-rank p = 0.008) were significantly different between the groups with low SUVmax values (n = 18) and high SUVmax values (n = 20). Furthermore, the primary tumor's SUVmax value was related to pathological vascular invasion (p = 0.045) and distant metastasis (p = 0.042).

CONCLUSION

The SUVmax of the primary tumor is a predictor of postoperative survival for clinical stage IA esophageal cancer. Thus, using fluorodeoxyglucose-positron emission tomography to evaluate the primary tumor's glucose metabolism may reflect the tumor's grade and potentially compensate for inaccuracies in tumor-node-metastasis staging.

Efficacy of 4'-[methyl-11C] thiothymidine PET/CT before and after neoadjuvant therapy for predicting therapeutic responses in patients with esophageal cancer: a pilot study

Background

4′-[Methyl-11C] thiothymidine (4DST) has been introduced as a new cell proliferation imaging PET tracer that incorporates into DNA directly. The aim of this prospective study was to evaluate the efficacy of 4DST PET/CT for predicting responses to neoadjuvant therapy in patients with esophageal cancer comparing with FDG PET/CT.

Methods

Twenty-six patients who had pre- and post-therapeutic 4DST and FDG PET/CT and underwent esophagectomy following neoadjuvant therapy were used for the analysis. Based on pathological findings, patients were divided into two groups: non-responders and responders. The maximum standardized uptake value (SUVmax), metabolic tumor volume, total lesion glycolysis, and total lesion proliferation of the primary lesion were measured for FDG and 4DST PET.

Results

The pathological diagnosis revealed 16 responders and 10 non-responders. Non-responders showed significantly higher 4DST post-therapeutic SUVmax (_postSUVmax) than responders, whereas FDG _postSUVmax showed no statistically significant difference (non-responders vs. responders: 4DST, 6.7 vs. 3.3, p = 0.001; FDG, 6.1 vs. 4.5, p = 0.11). Responders showed a greater reduction in percentage changes of 4DST and FDG SUVmax (ΔSUVmax) from baseline to post-therapeutic PET (non-responders vs. responders: 4DST, − 2.9% vs. − 56.7%, p < 0.001; FDG, − 36.3% vs. − 72.6%, p < 0.001). In ROC analysis, ΔSUVmax and _postSUVmax with 4DST provided great diagnostic performance for predicting responses (area under the curve: 4DST ΔSUVmax = 0.92, 4DST _postSUVmax = 0.88).

Conclusions

4DST PET/CT has a great potential for predicting pathologic response to neoadjuvant therapy in patients with esophageal cancer; it may be slightly superior to that with FDG PET/CT.

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.

Evaluation of Prognostic Factors for Esophageal Squamous Cell Carcinoma Treated with Neoadjuvant Chemoradiotherapy Followed by Surgery

BACKGROUND

Intensive trimodality therapy is needed for locally advanced esophageal squamous cell carcinoma (ESCC). However, some patients develop recurrence and die of cancer even after trimodality therapy.

METHODS

We evaluated prognostic factors based on data from 125 patients with ESCC who underwent neoadjuvant chemoradiotherapy (NCRT) comprising concurrent chemotherapy and 40 Gy of radiation, followed by curative-intent esophagectomy.

RESULTS

Thirty-four (27.2%) patients achieved a pathological complete response (pCR) after NCRT. The 5-year recurrence-free (RFS) and overall survival (OS) rates of all patients were 49.2 and 52.9%, respectively, and were significantly better for patients with pCR than without pCR (p = 0.01 and 0.02, respectively). Univariate and multivariate analyses selected performance status [PS 0 vs. 1: hazard ratio (HR) 2.05; 95% confidence interval (CI) 1.30-4.84; p = 0.01] and ypN (0 vs. 1: HR 2.33; 95% CI 1.12-4.84; p = 0.02; 0 vs. 2/3: HR 3.73; 95% CI 1.68-8.28; p = 0.001) as independent covariates for RFS. Furthermore, PS (0 vs. 1; HR 2.94; 95% CI 1.51-5.72; p = 0.002) and ypN (0 vs. 1; HR 2.26; 95% CI 1.09-4.69; p = 0.03; 0 vs. 2/3: HR 3.90; 95% CI 1.79-8.48; p = 0.001) were also independent covariates for OS.

CONCLUSIONS

Performance status 1 and ypN+ were significantly associated with a poor prognosis after trimodality therapy for ESCC.

Long-term results of neoadjuvant chemoradiotherapy using cisplatin and 5-fluorouracil followed by esophagectomy for resectable, locally advanced esophageal squamous cell carcinoma

This study retrospectively evaluated the long-term results of neoadjuvant chemoradiotherapy (NCRT) followed by esophagectomy for the patients with resectable, locally advanced esophageal squamous cell carcinoma (ESCC). Altogether, 49 patients treated from 2008 to 2012 were analyzed. Chemotherapy consisted of 5-fluorouracil and cisplatin. Radiotherapy was performed with a total dose of 40 Gy in 20 fractions for primary tumor, metastatic lymph nodes, and elective nodal area. Subsequently, transthoracic esophagectomy with extensive lymphadenectomy was performed. The median follow-up time for the survivors was 86 (range, 55-111) months. Pathological complete response from NCRT was observed in 17 (35%) patients. The 5-year overall survival and relapse-free survival rates were 56% [95% confidence interval (CI): 43-71%] and 55% (95% CI: 41-69%), respectively. The 5-year locoregional control rate was 84% (95% CI: 74-95%). Multivariate analyses revealed body mass index, N-factor, and %ΔSUVmax as significant factors for overall survival. Recurrences and within-irradiation field failure were observed in 16 (31%) and 4 (8%) patients, respectively. Toxicities of NCRT were generally mild. Postoperative Grade IIIb or worse complications were seen in 14% of patients, including one Grade V case (2%). The 5-year incidence rate of late complications of Grade 3 or worse was 22% (95% CI: 7-36%). The cumulative 5-year incidence rate of metachronous malignancies was 13% (95% CI: 1-26%). NCRT followed by esophagectomy for patients with resectable, locally advanced ESCC showed favorable locoregional control and overall survival, with acceptable postoperative complications. Long-term careful follow-up for late complications and metachronous malignancies is needed.

Preoperative prediction of a pathologic complete response of esophageal squamous cell carcinoma to neoadjuvant chemoradiotherapy

BACKGROUND

The accurate prediction of a pathologic complete response (ypT0N0M [LYM] 0 ypStage 0) before operation is essential for selecting appropriate strategies for treating esophageal cancer after neoadjuvant chemoradiotherapy.

METHODS

We reviewed 130 consecutive patients with esophageal squamous cell carcinoma who were evaluated preoperatively using upper gastrointestinal endoscopy, computed tomography, and 18F-fluorodeoxyglucose-positron emission tomography after neoadjuvant chemoradiotherapy and subsequently underwent esophagectomy. Our aim was to determine the diagnostic abilities of computed tomography, 18F-fluorodeoxyglucose-positron emission tomography, and endoscopy to predict preoperatively a pathologic complete response of the primary site of the locally advanced esophageal squamous cell carcinoma and associated lymph nodes to trimodal neoadjuvant chemoradiotherapy. Associations between clinical complete response (ycT0N0M [LYM] 0 ycStage 0) and pathologic complete response were investigated preoperatively.

RESULTS

Twenty-nine (22.3%) and 43 (33.1%) patients, respectively, achieved clinical complete response and pathologic complete response, which were associated (P=.001). The sensitivity and specificity, as well as the positive and negative predictive values of clinical complete response to define pathologic complete response were 39.5%, 86.2%, 58.6%, and 74.3%, respectively. Univariate and multivariate analyses selected clinical complete response as the sole independent preoperative predictor of pathologic complete response (clinical complete responses versus non-clinical complete responses: odds ratio: 0.26, 95% confidence interval, 0.10-0.65, P=.004). Recurrence-free and overall survival (OS) rates were better in patients with than in those without clinical complete response (5-year recurrence-free and overall survival: 69.0% vs 41.4% and 75.9% vs 45.0%, respectively, both P=.02). Furthermore, clinical complete response was an independent preoperative predictor of recurrence-free survival (clinical complete response versus nonclinical complete response: hazard ratio: 2.20, 95% confidence interval, 1.08-4.45, P=.03).

CONCLUSION

Although pathologic complete response was predictable preoperatively to some extent, the accuracy was somewhat low. Considerable caution should be exercised when selecting the watch-and-wait approach with operation as needed and omitting planned operative intervention even for patients who achieve clinical complete response after neoadjuvant chemoradiotherapy.

Perioperative Risk Calculator Predicts Long-Term Oncologic Outcome for Patients with Esophageal Carcinoma

BACKGROUND

Few risk models have been provided to predict long-term prognosis after esophagectomy. This study investigated the reliability of a risk calculator as well as classification and regression trees analysis for predicting long-term prognosis after esophagectomy for esophageal cancer.

METHODS

The study enrolled 438 patients who underwent esophagectomy at Keio University Hospital, Tokyo, Japan, between July 2000 and June 2016. Patients who underwent R0 or R1 resection or esophagectomy with combined resection of other organs were included. The authors investigated the usefulness of a risk model for 30-day mortality and operative mortality described in their previous report for predicting long-term prognosis after esophagectomy.

RESULTS

The 438 patients (377 men and 61 women) in this study had a 5-year overall survival (OS) rate of 62.8% and a disease-free survival rate of 54.3%. The OS was higher for the patients with 30-day mortality risk model values lower than 0.675% than for those with values higher than 0.675% (p < 0.001). The cutoff values for prediction were shown to be significant risk factors in the multivariate analysis. The risk calculator was validated by comparing the cutoff values with Harrell's C-index values of clinical stage. For overall risk, the C-index of operative mortality was 0.697, and the C-index of cStage was 0.671.

CONCLUSIONS

The risk calculator was useful for predicting recurrence and death after esophagectomy. Furthermore, because the C-index of the risk model for operative mortality was higher than for clinical tumor-node-metastasis stage, this risk-scoring system may be more useful clinically.