Determinants of response to neoadjuvant chemotherapy for esophageal cancer using 18F-fluorodeoxiglucose positron emission tomography (18F-FDG-PET)

Remarkable response as a new indicator for endoscopic evaluation of local efficacy of non-surgical treatments for esophageal cancer

In Japan, standard of care of the patients with resectable esophageal cancer is neoadjuvant chemotherapy (NAC) followed by esophagectomy. Patients unfitted for surgery or with unresectable locally advanced esophageal cancer are generally indicated with definitive chemoradiotherapy (CRT). Local disease control is undoubtful important for the management of patients with esophageal cancer, therefore endoscopic evaluation of local efficacy after non-surgical treatments must be essential. The significant shrink of primary site after NAC has been reported as a good indicator of pathological good response as well as favorable survival outcome after esophagectomy. And patients who could achieve remarkable shrink to T1 level after CRT had favorable outcomes with salvage surgery and could be good candidates for salvage endoscopic treatments. Based on these data, "Japanese Classification of Esophageal Cancer, 12th edition" defined the new endoscopic criteria "remarkable response (RR)", that means significant volume reduction after treatment, with the subjective endoscopic evaluation are proposed. In addition, the finding of local recurrence (LR) at primary site after achieving a CR was also proposed in the latest edition of Japanese Classification of Esophageal Cancer. The findings of LR are also important for detecting candidates for salvage endoscopic treatments at an early timing during surveillance after CRT. The endoscopic evaluation would encourage us to make concrete decisions for further treatment indications, therefore physicians treating patients with esophageal cancer should be well-acquainted with each finding.

Role of (F-18) Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Prediction of Response to Neoadjuvant Therapy in Esophageal Cancer: Correlation with Pathological Response and Survival

Purpose

The purpose of this study is to assess the correlation between metabolic response with fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and pathological response in patients with locally advanced esophageal cancer treated with neoadjuvant chemoradiotherapy and to study FDG-PET parameters for the prediction of pathological response and outcome.

Methods

Twenty-five patients with locally advanced esophageal cancer underwent two FDG-PET/CT scans for initial staging and after neoadjuvant chemoradiotherapy. FDG uptake in the primary tumor was calculated in both scans (SUVmax, SULpeak, and TLG). Metabolic response was assessed according to the reduction of PET parameters: complete response (mCR = 100%), partial response (mPR ≥50%), and no response (mNR ≤50%). Pathological response was also classified as complete (pCR), partial (pPR), or no response (pNR). Patients were followed up (range, 8-99 months) determining free-disease interval (FDI) and overall survival (OS).

Results

Two patients were excluded due to exitus for nonesophageal-related causes. The metabolic response was observed in 18/23 remaining patients (3mCR, 15 mPR), of which 12/18 patients showed a pathological response (3 pCR, 9 pPR). A major discrepancy was observed in 2 mNR patients who achieved pPR. FDI and OS were longer in patients with metabolic response than nonresponders, but no statistical difference was found. No significant correlation was found between PET parameters and pathological response, FDI, and OS.

Conclusions

FDG-PET/CT is a useful technique to assess response to neoadjuvant chemoradiotherapy in esophageal cancer. Although in this preliminary study, no correlation between metabolic and pathologic response was found and no statistical differences between responders and nonresponders were observed, a tendency of longer FDI and OS was apparently found in responders patients.

Comparing a PD-L1 inhibitor plus chemotherapy to chemotherapy alone in neoadjuvant therapy for locally advanced ESCC: a randomized Phase II clinical trial : A randomized clinical trial of neoadjuvant therapy for ESCC

BACKGROUND

A Phase II study was undertaken to evaluate the safety and efficacy of the neoadjuvant socazolimab, a novel PD-L1 inhibitor, in combination with nab-paclitaxel and cisplatin for locally advanced esophageal squamous cell carcinoma (ESCC).

METHODS

Sixty-four patients were randomly divided between the Socazolimab + nab-paclitaxel + cisplatin (TP) arm (n = 32) and the control arm (n = 32), receiving either socazolimab (5 mg/kg intravenously (IV), day 1) or a placebo with nab-paclitaxel (125 mg/m² IV, day 1/8) and cisplatin (75 mg/m² IV, day 1) repeated every 21 days for four cycles before surgery. The primary endpoint was major pathological response (MPR), and the secondary endpoints were pathological complete response (pCR), R0 resection rate, event-free survival (EFS), overall survival (OS), and safety.

RESULTS

A total of 29 (90.6%) patients in each arm underwent surgery, and 29 (100%) and 28 (98.6%) patients underwent R0 resection in the Socazolimab + TP and Placebo + TP arms, respectively. The MPR rates were 69.0 and 62.1% (95% Confidence Interval (CI): 49.1-84.0% vs. 42.4-78.7%, P = 0.509), and the pCR rates were 41.4 and 27.6% (95% CI: 24.1-60.9% vs. 13.5-47.5%, P = 0.311) in the Socazolimab + TP and Placebo + TP arms, respectively. Significantly higher incidence rates of ypT0 (37.9% vs. 3.5%; P = 0.001) and T downstaging were observed in the Socazolimab + TP arm than in the Placebo + TP arm. The EFS and OS outcomes were not mature.

CONCLUSIONS

The neoadjuvant socazolimab combined with chemotherapy demonstrated promising MPR and pCR rates and significant T downstaging in locally advanced ESCC without increasing surgical complication rates.

TRIAL REGISTRATION

Registration name (on clinicaltrials.gov): A Study of Anti-PD-L1 Antibody in Neoadjuvant Chemotherapy of Esophageal Squamous Cell Carcinoma.

REGISTRATION NUMBER

NCT04460066.

Maximum standardized uptake value change rate before and after neoadjuvant chemotherapy can predict early recurrence in patients with locally advanced esophageal cancer: a multi-institutional cohort study of 220 patients in Japan

BACKGROUND

Neoadjuvant chemotherapy (NAC) followed by esophagectomy can improve the prognosis of locally advanced esophageal cancer (LAEC). However, LAEC reportedly recurred in 17-21% of patients within 6 months post surgery. Thus, current treatment strategies may be inadequate for LAECs with poor prognosis. Preoperative identification of patients with poor prognosis might aid in modification of treatment strategies. This study aimed to evaluate the usefulness of the maximum standardized uptake value change rate (ΔSUV_max) in predicting treatment effects on the primary lesion, prognosis, and LAEC recurrence.

METHODS

This study involved 220 esophageal cancer patients who underwent esophagectomy after NAC at three facilities in Japan. The optimal cut-off point for ΔSUV_max in predicting tumor regression grade (TRG) was calculated and used to assess the correlation between ΔSUV_max and postoperative survival.

RESULTS

The optimal cut-off point for ΔSUV_max was 0.5. The 5-year overall survival rate in patients with ΔSUV_max ≥ 0.5 was significantly higher than that in patients with ΔSUV_max < 0.5 (71.5% vs. 50.5%, P = 0.001). Multivariate analysis identified ΔSUV_max (hazards ratio, 0.496; P = 0.004) as an independent prognostic factor. Among 199 patients evaluated for recurrence, 24 (12.1%) showed recurrence within 6 months post surgery. Univariate analysis revealed ΔSUV_max as the only predictor for early recurrence (odds ratio, 0.222; P = 0.004).

CONCLUSION

ΔSUV_max before and after NAC is clinically useful as it could help predict TRG, survival outcome, and early recurrence within 6 months post esophagectomy and is easily obtainable in general clinical practice. We believe that it may also help determine suitable treatment strategies for LAEC.

Platelet-to-Lymphocyte Ratio Multiplied by the Cytokeratin-19 Fragment Level as a Predictor of Pathological Response to Neoadjuvant Chemotherapy in Esophageal Squamous Cell Carcinoma

Background

The standard treatment for resectable advanced esophageal squamous cell carcinoma in Japan is surgery followed by neoadjuvant chemotherapy, and it is important to predict the effect of neoadjuvant chemotherapy before treatment. Therefore, this study aims to extract conventional blood examination data, such as tumor markers and/or inflammatory/nutritional index levels, that can predict the pathological response of patients with esophageal squamous cell carcinoma to neoadjuvant chemotherapy.

Methods

We retrospectively analyzed the medical records of 66 patients with thoracic esophageal squamous cell carcinoma who received neoadjuvant chemotherapy, followed by curative esophagectomy at Tottori University Hospital between June 2009 and December 2019.

Results

We demonstrated that the product of the platelet-to-lymphocyte ratio (PLR) multiplied by the cytokeratin-19 fragment (CYFRA) level, which was termed "PLR-CYFRA," is the most accurate indicator that predicts the pathological response to neoadjuvant chemotherapy, with the highest area under the curve [0.795 (95% confidence interval: 0.665-0.925), P < 0.001] in receiver operating characteristic analyses. Therefore, we divided patients into the PLR-CYFRA^Low (< 237.6, n = 21) and PLR-CYFRA^High (≥ 237.6, n = 45) groups and found that the percentage of PLR-CYFRA^Low was significantly higher in patients with a better pathological response (P < 0.001). Furthermore, patients with good pathological response had significantly better prognoses in terms of disease-specific survival (P = 0.014), recurrence-free survival (P = 0.014), and overall survival (P = 0.032). In the multivariate analysis, PLR-CYFRA was an independent predictor of the pathological response of patients with esophageal squamous cell carcinoma to neoadjuvant chemotherapy (P = 0.002).

Conclusion

Pretreatment PLR-CYFRA might be a useful and simple tool that predicts the pathological effect of neoadjuvant chemotherapy in esophageal squamous cell carcinoma.

Baseline 18F-FDG PET/CT quantitative parameters as prognostic factors in esophageal squamous cell cancer

AIM

To determine the utility of [¹⁸F]FDG PET/CT quantitative parameters as prognostic factors for the response to neoadjuvant treatment, progression-free survival (PFS) and cancer-specific survival (CSS) in patients with esophageal squamous cell carcinoma (SCC).

MATERIAL AND METHODS

Thirty patients (29 men) diagnosed with SCC were retrospectively evaluated over a 6-year interval. Metabolic parameters were determined: maximum SUV (SUVmax), mean SUV (SUVmed), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) from baseline PET/CT study. After treatment with chemotherapy and/or radiotherapy, response to treatment and patient survival were assessed. The comparison of parameters between groups of responders and non-responders was carried out using a Mann-Whitney U test ROC curves and the Kaplan-Meier method were used for analysis of prognostic factors and survival curves.

RESULTS

The average follow-up was 22.4 months, with 22 recurrence-progressions and 25 deaths. Significant differences were demonstrated between responders and non-responders with respect to tumor size, MTV and TLG. Survival analysis found significant differences for SCE and CSS depending on these three parameters.

CONCLUSION

Metabolic parameters MTV and TLG, and tumor size were prognostic factors for neoadjuvant treatment response, PFS, and CSS in patients diagnosed with SCC. Neither SUVmax nor SUVmed were predictive for any of the evaluation criteria. Results could help to personalize patient treatment.

Baseline 18F-FDG PET/CT quantitative parameters as prognostic factors in esophageal squamous cell cancer

AIM

To determine the utility of 18F-FDG PET/CT quantitative parameters as prognostic factors for the response to neoadjuvant treatment, progression-free survival (PFS) and cancer-specific survival (CSS) in patients with esophageal squamous cell carcinoma (SCC).

MATERIAL AND METHODS

Thirty patients (29 men) diagnosed with SCC were retrospectively evaluated over a 6-year interval. Metabolic parameters were determined: maximum SUV (SUVmax), mean SUV (SUVmed), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) from baseline PET/CT study. After treatment with chemotherapy and/or radiotherapy, response to treatment and patient survival were assessed. The comparison of parameters between groups of responders and non-responders was carried out using a Mann-Whitney U test. ROC curves and the Kaplan-Meier method were used for analysis of prognostic factors and survival curves.

RESULTS

The average follow-up was 22.4months, with 22 recurrence-progressions and 25 deads. Significant differences were demonstrated between responders and non-responders with respect to tumor size, MTV and TLG. Survival analysis found significant differences for SCE and CSS depending on these three parameters.

CONCLUSION

Metabolic parameters MTV and TLG, and tumor size were prognostic factors for neoadjuvant treatment response, PFS, and CSS in patients diagnosed with SCC. Neither SUVmax nor SUVmed were predictive for any of the evaluation criteria. Results could help to personalize patient treatment.

Predicting tumor response and prognosis to neoadjuvant chemotherapy in esophageal squamous cell carcinoma patients using PERCIST: a multicenter study in Japan

PURPOSE

To investigate the usefulness of the positron emission tomography response criteria in solid tumors 1.0 (PERCIST1.0) for predicting tumor response to neoadjuvant chemotherapy and prognosis and determine whether PERCIST improvements are necessary for esophageal squamous cell carcinoma (ESCC) patients.

PATIENTS AND METHODS

We analyzed the cases of 177 ESCC patients and examined the association between PERCIST and their pathological responses. Associations of whole-PERCIST with progression-free survival (PFS) and overall survival (OS) were evaluated by a Kaplan-Meier analysis and Cox proportional hazards model. To investigate potential PERCIST improvements, we used the survival tree technique to understand patients' prognoses.

RESULTS

There were significant correlations between the pathologic response and PERCIST of primary tumor (p < 0.001). The optimal cutoff value of the primary tumors' SULpeak response to classify pathologic responses was -50.0%. The diagnostic accuracy of SULpeak response was 87.3% sensitivity, 54.1% specificity, 68.9% accuracy, positive predictive value 60.5%, and negative predictive value 84.1%. Whole-PERCIST was significantly associated with PFS and OS. The survival tree results indicated that a high reduction of the whole SULpeak response was significantly correlated with the patients' prognoses. The cutoff values for the separation of prognoses were - 52.5 for PFS and - 47.1% for OS.

CONCLUSION

PERCIST1.0 can help predict tumor responses and prognoses. However, ¹⁸F-FDG-PET/CT tends to underestimate residual tumors in histopathological response evaluations. Modified PERCIST, in which the partial metabolic response is further classified by the SULpeak response (-50%), might be more appropriate than PERCIST1.0 for evaluating tumor responses and stratifying high-risk patients for recurrence and poor prognosis.

Total Lesion Glycolysis Ratio in Positron Emission Tomography/Computed Tomography Images During Neoadjuvant Chemotherapy Can Predict Pathological Tumor Regression Grade and Prognosis in Patients with Locally Advanced Squamous Cell Carcinoma of the Esophagus

BACKGROUND

The usefulness of quantitating tumor lesion glycolysis (TLG) from ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) findings as a tool for determining the effect of neoadjuvant chemotherapy (NAC) in esophageal squamous cell carcinoma (ESCC) has not yet been established.

METHODS

The cohort of this retrospective study comprised 46 patients who had undergone NAC and subsequent esophagectomy for locally advanced ESCC between January 2008 and December 2017. PET/CT was conducted before and after NAC to assess its therapeutic effect. Associations between changes in TLG values during NAC and clinicopathological findings, pathological tumor regression grade (TRG), and prognosis were assessed.

RESULTS

Most patients received two courses of DCF (Docetaxel, Cisplatin, and Fluorouracil) as NAC. The mean TLG value of the primary tumor decreased significantly after NAC. The median follow-up period was 41 months. The Kaplan-Meier method, analyzed by log-rank test, showed that low TLG ratio (≤ 0.4) and low SUV_max ratio (≤ 0.6) were associated with favorable survival outcomes (P = 0.0073 and P = 0.032, respectively). Univariate and multivariate analysis revealed that TLG ratio and achievement of pathological cure were independent prognostic factors for overall survival. TLG ratio was also associated with pathological TRG (TRG 0-1a vs 1b-3) (P = 0.0016).

CONCLUSIONS

TLG ratio before and after NAC is clinically useful in predicting both histological response and survival outcome after NAC and subsequent esophagectomy in patients with 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.

Prognostic Significance of C-reactive Protein-to-prealbumin Ratio in Patients with Esophageal Cancer

Background

The prognostic value of combination of C-reactive protein and prealbumin (CRP/PAlb) in esophageal cancer remains unclear.

Methods

We enrolled 167 esophageal cancer patients who underwent curative esophagectomy. Univariate and multivariate analyses were performed to determine the prognostic significance of various markers, including CRP-to-albumin (CRP/Alb) ratio, modified Glasgow prognostic score, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and prognostic nutritional index.

Results

Receiver operating characteristic analysis revealed the optimal cut-off value of each inflammatory factor, and CRP/PAlb ratio had the greatest discriminative power in predicting recurrence-free survival (RFS) among the examined measures (AUC 0.668). The 5-year overall survival and RFS rates were significantly lower in patients with high CRP/PAlb ratio than in those with low CRP/PAlb ratio (P < 0.001, P = 0.001, respectively). In the univariate analysis, RFS was significantly worse in patients with low BMI, T2 or deeper tumor invasion, positive lymph node metastasis, positive venous invasion, high CRP/PAlb ratio, high CRP/Alb ratio, high NLR, and high LMR. Multivariate analysis revealed that CRP/PAlb, but not CRP/Alb, was an independent prognostic factor along with lymph node metastasis.

Conclusion

CRP/PAlb ratio was useful for predicting the prognosis of esophageal cancer patients.

A Hopeful Natural Product, Pristimerin, Induces Apoptosis, Cell Cycle Arrest, and Autophagy in Esophageal Cancer Cells

Esophageal cancer is one of the most common malignant digestive diseases worldwide. Although many approaches have been established for the treatment of esophageal cancer, the survival outcome has not improved. Pristimerin is a quinone methide triterpenoid with anticancer, antiangiogenic, anti-inflammatory, and antiprotozoal activities. However, the role of pristimerin in cancers such as esophageal cancer is unclear. In this study, we investigated the role and mechanisms of action of pristimerin in esophageal cancer. First, we found that pristimerin can induce apoptosis in esophageal cancer in vivo and in vitro. CCK-8 and clonogenic assays showed that pristimerin decreased the growth of Eca109 cells. In addition, we found that pristimerin decreased the protein expression of CDK2, CDK4, cyclin E, and BCL-2 and increased the expression of CDKN1B. Meanwhile, pristimerin elevated the ratio of LC3-II/LC3-I. Otherwise, downregulation of CDKN1B can reduce the esophageal cancer tumor growth induced by pristimerin. In conclusion, our findings revealed an important role of pristimerin in esophageal cancer and suggest that pristimerin might be a potential therapeutic agent for this cancer.

Immunoregulatory influence of abundant MFG-E8 expression by esophageal cancer treated with chemotherapy

Milk fat globule‐epidermal growth factor factor 8 (MFG‐E8) is secreted from macrophages and is known to induce immunological tolerance mediated by regulatory T cells. However, the roles of the MFG‐E8 that is expressed by cancer cells have not yet been fully examined. Expression of MFG‐E8 was examined using immunohistochemistry in surgical samples from 134 patients with esophageal squamous cell carcinoma. The relationships between MFG‐E8 expression levels and clinicopathological factors, including tumor‐infiltrating lymphocytes, were evaluated. High MFG‐E8 expression was observed in 23.9% of the patients. The patients with tumors highly expressing MFG‐E8 had a significantly higher percentage of neoadjuvant chemotherapy (NAC) history (P < .0001) and shorter relapse‐free survival (P = 0.012) and overall survival (OS; P = .0047). On subgroup analysis, according to NAC history, patients with high MFG‐E8 expression had significantly shorter relapse‐free survival (P = .027) and OS (P = .0039) only when they had been treated with NAC. Furthermore, tumors with high MFG‐E8 expression had a significantly lower ratio of CD8⁺ T cells/regulatory T cells in tumor‐infiltrating lymphocytes (P = .042) only in the patients treated with NAC, and those with a lower ratio had a shorter OS (P = .026). High MFG‐E8 expression was also found to be an independent prognostic factor in multivariate analysis. The abundant MFG‐E8 expression in esophageal squamous cell carcinoma might have a negative influence on the long‐term survival of patients after chemotherapy by affecting T‐cell regulation in the tumor microenvironment.

High Expression of the Mitophagy-Related Protein Pink1 is Associated with a Poor Response to Chemotherapy and a Poor Prognosis for Patients Treated with Neoadjuvant Chemotherapy for Esophageal Squamous Cell Carcinoma

BACKGROUND

Autophagy plays a major role in cellular homeostasis and is implicated in cancer progression. Damaged mitochondria are scavenged and eliminated by mitochondrial autophagy, referred to as mitophagy, which can promote cancer cell survival. This study investigated the expression and effects of the autophagy-related protein LC3 and the mitophagy-related protein Pink1 in human esophageal squamous cell carcinoma (ESCC).

METHODS

Both LC3 and Pink1 were analyzed by immunohistochemistry in tissues from 217 ESCC patients, including 159 patients undergoing neoadjuvant chemotherapy. The relationships between LC3 and Pink1 expression and various clinicopathologic factors were determined. In vitro assays were performed to assess the role of LC3 and Pink1 in ESCC chemoresistance.

RESULTS

High LC3 expression was observed in 47.9% and high Pink1 expression in 48.4% of the ESCC patients. Pink1 expression was significantly higher in patients who underwent chemotherapy than in patients who did not (p = 0.032). High LC3 and Pink1 expression was significantly correlated with poor response to chemotherapy (p = 0.004 and p < 0.001, respectively), and high expression of Pink1, but not LC3, was significantly correlated with a poor prognosis for patients treated with preoperative chemotherapy (p = 0.007). Multivariate analysis identified Pink1 expression as an independent prognostic factor (p = 0.042). In vitro assays demonstrated that LC3-II and Pink1 expression increased after chemotherapeutic treatment in the ESCC cell line, and inhibition of autophagy and mitophagy using chloroquine and siPink1, respectively, restored chemosensitivity.

CONCLUSIONS

High expression of Pink1 is associated with chemoresistance and a poor prognosis for ESCC patients undergoing neoadjuvant chemotherapy.

Significance of baseline FDG-PET/CT scan as a method of staging regional lymph nodes in patients with operable distal oesophageal or gastroesophageal junction adenocarcinoma

BACKGROUND

The new American Joint Committee on Cancer eighth edition (AJCC8) staging is the first to describe separate clinical and pathology staging systems, but still has low performance to predict prognosis in patients with oesophageal/gastroesophageal junction (O/GOJ) adenocarcinoma, who are candidates for surgery. Recent studies have demonstrated that O/GOJ cancer patients with 18F-fluorodeoxyglucose (FDG) avid regional lymph nodes (RLNs) may have poor prognosis. The aim of our study was to examine whether the baseline assessment of the FDG uptake of RLN improves the prognostic accuracy of the new AJCC8 staging.

PATIENTS AND METHODS

This single-centre retrospective study included patients with operable FDG avid O/GOJ adenocarcinoma treated with perioperative chemotherapy. All patients were reclassified according to the new AJCC8 clinical staging. Prognostic factors for time-to-progression (TTP) and overall survival (OS) were explored.

RESULTS

Of 430 patients included in the study, 180 (41.9%) had FDG avid RLN at baseline PET/CT scan before starting perioperative chemotherapy. The presence of FDG avid RLN was significantly and independently associated with shorter TTP and OS, especially in clinical stage III patients (p < .001 in both cases). Stage III patients with FDG avid RLN had similar TTP and OS to those with stage IVA. Classifying stage III patients with FDG avid RLN into stage IVA led to a significant improvement of the prognostic accuracy of the new AJCC8 clinical staging system (Harrell's concordance index improved from 0.555 to 0.588, p < .001). Of 430 patients starting perioperative chemotherapy, 332 underwent radical tumour resection. The presence of FDG avid RLN before starting perioperative chemotherapy could additionally predict a significantly shorter postoperative time-to-relapse and OS (p < .001 in both cases).

CONCLUSIONS

We propose that the incorporation of RLN status (by FDG PET/CT scan) into the AJCC8 staging system of O/GOJ adenocarcinoma improves its prognostic accuracy and may also improve treatment stratification.

Importance of positron emission tomography for assessing the response of primary and metastatic lesions to induction treatments in T4 esophageal cancer

BACKGROUND

There is no consensus strategy for treatment of T4 esophageal cancer, and because of this, a better evaluation of treatment response is crucial to establish personalized therapies. This study aimed to establish a useful system for evaluating treatment response in T4 esophageal cancer.

METHODS

This study included 130 patients with cT4 esophageal cancer without distant metastasis who underwent ¹⁸F-fluorodeoxyglucose-positron emission tomography before and after a series of induction treatments comprising chemoradiation or chemotherapy. We evaluated the maximal standardized uptake value and treatment response.

RESULTS

The mean ± standard deviation of standardized uptake value in the primary tumor before and after induction treatments were 13.8 ± 4.4 and 5.4 ± 4.1, respectively, and the mean standardized uptake value decrease was 58.4%. The most significant difference in survival between positron emission tomography-primary tumor responders and nonresponders was at a decrease of 60% standardized uptake value, based on every 10% stepwise cutoff analysis (2-year cause-specific survival: 60.2 vs 23.5%; hazard ratio = 2.705; P < .0001). With this cutoff value, the resectability (P = .0307), pathologic response (P = .0004), and pT stage (P < .0001) were associated with positron emission tomography-primary tumor response. Univariate analysis of 2-year cause-specific survival indicated a correlation between cause-specific survival and clinical stages according to TNM classification, esophageal perforation, positron emission tomography-primary tumor response, lymph node status evaluated by positron emission tomography before and after induction treatments, and operative resection. Multivariate analysis further identified positron emission tomography-primary tumor response (hazard ratio = 2.354; P = .0107), lymph node status evaluated by positron emission tomography after induction treatments (hazard ratio = 1.966; P = .0089), and operative resection (hazard ratio = 2.012; P = .0245) as independent prognostic predictors.

CONCLUSION

Positron emission tomography evaluation of the response of primary and metastatic lesions to induction treatments is important to formulate treatment strategies for cT4 esophageal cancer.

Is 18F-FDG-PET useful for predicting R0 resection after induction therapy for initially unresectable locally advanced esophageal carcinoma?

OBJECTIVE

Induction therapy followed by surgery is a promising strategy for esophageal cancer patients with invasion of the trachea/bronchus or aorta. However, no diagnostic criteria have been established to diagnose whether R0 resection can be performed. We investigated whether ¹⁸F-2-deoxy-D-glucose positron emission tomography (¹⁸F-FDG-PET) and other modalities are useful for predicting R0 resection.

METHODS

Fifty-seven patients with esophageal cancer invading the trachea/bronchus or aorta who underwent induction therapy followed by surgery were enrolled. We divided the participants into two groups, an R0 resection group (n = 43) and a non-R0 resection group (n = 14), and then compared the between-group results of three modalities, including computed tomography (CT), endoscopy and ¹⁸F-FDG-PET, before and after induction therapy.

RESULTS

The post-maximal standardized uptake value (SUV_max) after induction therapy in the R0 resection group was significantly lower than that in the non-R0 resection group (4.4 vs. 6.6, p = 0.005). The receiver operating characteristic curve analysis showed that the cut-off value for the post-SUV_max based on ¹⁸F-FDG-PET prediction of R0 resection was 4.7. Furthermore, a tumor reduction rate of ≥44% on CT, no residual stenosis, and no deep ulcer on endoscopy were associated with R0 resection after induction therapy (p = 0.002, p = 0.091, and p = 0.059, respectively). Multivariate logistic analyses revealed that the tumor reduction rate on CT and post-SUV_max <4.7 in ¹⁸F-FDG-PET were independent factors for R0 resection.

CONCLUSIONS

The post-SUV_max determined by ¹⁸F-FDG-PET and the volume reduction rate based on CT scans were useful for predicting R0 resection after induction therapy for initially unresectable locally advanced esophageal carcinoma.

Serial imaging using [18F]Fluorodeoxyglucose positron emission tomography and histopathologic assessment in predicting survival in a population of surgically resectable distal oesophageal and gastric adenocarcinoma following neoadjuvant therapy

Background and objectives

We retrospectively evaluated the value of PET/CT in predicting survival and histopathological tumour-response in patients with distal oesophageal and gastric adenocarcinoma following neoadjuvant treatment.

Methods

Twenty-one patients with resectable distal oesophageal adenocarcinoma and 14 with gastric adenocarcinoma between January 2002 and December 2011, who had undergone serial PET before and after neoadjuvant therapy followed by surgery, were enrolled. Maximum standard uptake value (SUVmax) and metabolic tumour volume were measured and correlated with tumour regression grade and survival.

Results

Histopathological tumour response (PR) is a stronger predictor of overall and disease-free survival compared to metabolic response. ∆%SUVmax ≥70% was the only PET metric that predicted PR (82.4% sensitivity, 61.5% specificity, p = 0.047). Histopathological non-responders had a higher risk of death (HR 8.461, p = 0.001) and recurrence (HR 6.385, p = 0.002) and similarly in metabolic non-responders for death (HR 2.956, p = 0.063) and recurrence (HR 3.614, p = 0.028). Ordinalised ∆%SUVmax showed a predictive trend for OS and DFS, but failed to achieve statistical significance.

Conclusions

PR was a stronger predictor of survival than metabolic response. ∆%SUVmax ≥70% was the best biomarker on PET that predicted PR and survival in oesophageal and gastric adenocarcinoma. Ordinalisation of ∆%SUVmax was not helpful in predicting primary outcomes.

Predictive value of repeated F-18 FDG PET/CT parameters changes during preoperative chemoradiotherapy to predict pathologic response and overall survival in locally advanced esophageal adenocarcinoma patients

INTRODUCTION

The goal of the current study was to investigate the predictive and prognostic values of repeated F-18 FDG PET/CT parameter changes for prediction of complete pathologic response (pCR) in patients with adenocarcinoma of locally advanced esophageal cancer (LAEC) who received preoperative concurrent chemoradiotherapy (PCRT).

METHODS

A total 53 patients with LAEC patients were included in the current study. All patients were evaluated by F-18 FDG PET/CT before and during chemoradiotherapy. The percent changes (∆, %) in F-18 FDG PET/CT parameters were used to predict pCR and to calculate overall survival (OS). The predictive value for pCR of F-18 FDG PET/CT cutoff values was determined by ROC analysis. The prognostic significance was assessed using Kaplan-Meier analysis.

RESULTS

pCR occurred in 15 patients (28.3 %). When ΔSUVmax > 23.5 % was used as cutoff, the sensitivity and specificity of F-18 FDG PET/CT for prediction of pCR were 100 % and 52.6, respectively. The AUC was 0.750 (95 % CI; 0.612-0.859), and standard error (SE) was 0.0633 (p = 0.0002). ΔMTV resulted in 80 % sensitivity, 76.3 % specificity, and 0.731 AUC (95 % CI; 0.591-0.843, SE = 0.077, p = 0.0027) for cutoff values >25.5 %. When ΔTLG > 44.8 % was used as cutoff, the sensitivity and specificity of F-18 FDG PET/CT for prediction of pCR were 100 and 65.8 %, respectively. The AUC was 0.893 (95 % CI; 0.777-0.961), and SE was 0.0431 (p < 0.0001). Kaplan-Meier analysis showed that high ΔSUVmax, ΔMTV, and ΔTLG were associated with improved OS.

CONCLUSION

In conclusion, the current study shows the capability of the changes (Δ) in repeated F-18 FDG PET/CT parameters to predict the achievement of pCR during PCRT in LAEC patients. Among the parameters, the ΔSUVmax, ΔMTV, and ΔTLG were predictors for pCR and well associated with OS.

Impact of number of [(18)F]fluorodeoxyglucose-PET-positive lymph nodes on survival of patients receiving neoadjuvant chemotherapy and surgery for oesophageal cancer

BACKGROUND

[(18) F]fluorodeoxyglucose (FDG)-PET has been used to evaluate the response of primary tumours to neoadjuvant therapy for oesophageal cancer. The clinical significance of the number of PET-positive nodes before and after therapy has not been investigated previously.

METHODS

[(18) F]FDG-PET was performed before and 2-3 weeks after completion of neoadjuvant chemotherapy to identify the number of PET-positive nodes, and these numbers were assessed in relation to metabolic changes in the primary tumour.

RESULTS

Of 302 patients in total, 90 had no PET-positive nodes, 83 had one, 59 had two and 70 patients had three or more positive nodes before therapy. After treatment, the numbers were: none in 207 patients, one in 59, two in 20 and three or more in 16 patients. The number of PET-positive nodes after treatment was influenced by both the number of PET-positive nodes before therapy and the response to preoperative therapy, and correlated with the number of metastatic lymph nodes. Overall survival was longer in patients who had no PET-positive nodes after treatment than in those who had one or more. Multivariable analysis identified the numbers of PET-positive nodes before and after chemotherapy as independent prognostic factors, together with clinical response, tumour depth and lymph node involvement.

CONCLUSION

The number of PET-positive nodes after treatment correlated with survival in patients with oesophageal cancer who underwent neoadjuvant chemotherapy.

Positron Emission Tomography (PET) in Oncology

Since its introduction in the early nineties as a promising functional imaging technique in the management of neoplastic disorders, FDG-PET, and subsequently FDG-PET/CT, has become a cornerstone in several oncologic procedures such as tumor staging and restaging, treatment efficacy assessment during or after treatment end and radiotherapy planning. Moreover, the continuous technological progress of image generation and the introduction of sophisticated software to use PET scan as a biomarker paved the way to calculate new prognostic markers such as the metabolic tumor volume (MTV) and the total amount of tumor glycolysis (TLG). FDG-PET/CT proved more sensitive than contrast-enhanced CT scan in staging of several type of lymphoma or in detecting widespread tumor dissemination in several solid cancers, such as breast, lung, colon, ovary and head and neck carcinoma. As a consequence the stage of patients was upgraded, with a change of treatment in 10%-15% of them. One of the most evident advantages of FDG-PET was its ability to detect, very early during treatment, significant changes in glucose metabolism or even complete shutoff of the neoplastic cell metabolism as a surrogate of tumor chemosensitivity assessment. This could enable clinicians to detect much earlier the effectiveness of a given antineoplastic treatment, as compared to the traditional radiological detection of tumor shrinkage, which usually takes time and occurs much later.