Randomized Phase II Study of PET Response-Adapted Combined Modality Therapy for Esophageal Cancer: Mature Results of the CALGB 80803 (Alliance) Trial

Determining the optimal radiation dose for locally advanced esophageal cancer: A pooled analysis of reconstructed individual patient data from randomized clinical trials

BACKGROUND

The optimal radiation dose of definitive concurrent chemoradiotherapy (dCCRT) for esophageal cancer (EC) has always been a concern in radiation oncology and has remained controversial for several decades, we performed a meta-analysis based on individual patient data (IPD) to explore the optimal dose.

METHODS

Randomized clinical trials (RCTs) comparing high-dose radiotherapy (HD-RT,≥59.4 Gy) with standard-dose radiotherapy (SD-RT, 50 Gy/50.4 Gy) were identified. Graphical reconstructive algorithms were employed to extract time-to-event outcomes from Kaplan-Meier curves presented in the original RCTs. Using reconstructed individual patient data, summary overall survival (OS), progression-free survival (PFS) and locoregional progression-free survival (LRPFS) for HD-RT versus SD-RT were recalculated. Hazard Ratios (HRs) of OS, PFS and LRPFS reported were also pooled by the fixed or random effects model.

RESULTS

Six RCTs, including 1722 patients, were included. IPD for OS, PFS, and LRPFS were from 1287, 462, and 722 patients, respectively. Overall, HD-RT had no significant benefits in 3-year OS (RR = 1.00, P = 0.990), 3-year progression-free survival (PFS) (RR = 0.96, P = 0.320) and 3-year locoregional progression-free survival (LRPFS) (RR = 0.88, P = 0.204), compared with SD-RT. Consistent with above results, the pooled HRs of OS, PFS and LRPFS for HD-RT versus SD-RT were 0.99 (P = 0.854), 0.94 (P = 0.628) and 0.91 (P = 0.410), respectively. However, HD-RT had higher grade ≥ 3 treatment-related adverse effects (TRAEs) (OR = 1.26, P = 0.025). Subgroup analyses were also performed based on the RT techniques, histology, size of the RT target, dose-escalation mode, and stage editions. We found that dose escalation, even in subgroups, did not benefit long-term survival but resulted in a higher incidence of grade ≥ 3 TRAEs.

CONCLUSION

The results provide robust evidence that corroborates current guidelines and supports the clinical practice of employing SD-RT. Additionally, it provides implications for the feasibility of further research into novel drug combinations (e.g., immunotherapy) rather than radiation dose escalation.

Initial reduction of the primary tumor or lymph nodes: which is the better prognostic factor in patients with esophageal squamous cell carcinoma receiving neoadjuvant chemotherapy followed by surgery?

BACKGROUND

Early response of the primary tumor (PT) to neoadjuvant chemotherapy (NAC) in patients with esophageal squamous cell carcinoma (ESCC) is considered a potential predictor of postoperative prognosis. However, the role of metastatic lymph nodes (LNs) remains poorly understood. This study aimed to compare the predictive value of early response in PT and LNs for postoperative prognosis.

METHODS

We enrolled 124 consecutive patients who received NAC-docetaxel, cisplatin, 5-fluorouracil (DCF) followed by surgery for ESCC between April 2010 and March 2020. Initial tumor reduction of the PT (ITR-PT) and LN (ITR-LN), defined as the percentage decrease in tumor shorter diameter after the first course of NAC-DCF, was evaluated using computed tomography. The optimal cut-off values of ITRs were determined using receiver operating characteristic curves and Cox regression models, and their relationship with recurrence-free survival (RFS) was analyzed.

RESULTS

The median ITR-PT and ITR-LN were 21.77% and -0.88%, respectively. The optimal cut-off values for predicting prognosis were approximately 10% for ITR-PT (hazard ratio [HR], 3.23; 95% confidence interval [CI], 1.84-5.64) and -10% for ITR-LN (HR, 2.20; 95% CI, 1.27-3.80). ITR-PT showed a greater impact on RFS (3-year RFS: ITR-PT ≥ 10%, 66.1%; ITR-PT < 10%, 18.4%; log-rank P < 0.001) compared with ITR-LN (3-year RFS: ITR-LN ≥ -10%, 64.1%; ITR-PT < -10%, 34.3%; log-rank P = 0.004). Multivariate analysis of RFS identified ypN, ITR-PT, and ITR-LN as independent prognostic factors.

CONCLUSIONS

Both ITR-PT and ITR-LN are promising predictors of survival in patients with ESCC who underwent NAC-DCF plus surgery. ITR-PT may be a stronger prognostic factor than ITR-LN.

Evolution of Therapeutics for Locally Advanced Upper Gastrointestinal Adenocarcinoma

Upper gastrointestinal (GI) malignancies, including esophageal, gastroesophageal junction (GEJ), and gastric adenocarcinomas, remain a major global health concern, with poor overall survival and high recurrence rate despite aggressive treatment. Patients with very early tumors (cT1a) can benefit from endoscopic therapy. However, patients with locally advanced disease require multimodal therapies that may combine surgery, radiation, and systemic therapies. This review provides a comprehensive overview of recent advancements in the treatment of locally advanced upper GI adenocarcinomas. Surgical resection remains the cornerstone of curative treatment, with perioperative chemotherapy emerging as the standard of care. While preoperative chemoradiation has demonstrated some benefits in esophageal and GEJ cancers, recent data suggest a more limited role for radiation going forward. Immunotherapy has shown some promise in both the adjuvant and perioperative settings but has yet to establish definitive survival benefit. The integration of HER2-targeted therapies into treatment regimens for HER2-positive locally advanced gastroesophageal cancers has not yielded significant improvements, underscoring the need for more effective strategies. Ongoing research focuses on better predictive biomarkers, personalized treatment approaches, and potential organ preservation strategies for patients achieving a clinical complete response. Continued advancements in treatment modalities and precision medicine are critical to improving survival for patients with locally advanced upper GI adenocarcinomas.

Trifluridine/Tipiracil and Oxaliplatin as Induction Chemotherapy in Resectable Esophageal and Gastroesophageal Junction Adenocarcinoma: A Phase II Study

BACKGROUND

Preoperative chemoradiation (CRT) followed by surgery for localized esophageal and gastroesophageal junction adenocarcinoma (EGAC) is a standard of care with a pathologic complete response (pCR) rate of 20%. We evaluated a novel combination of trifluridine/tipiracil with oxaliplatin as induction chemotherapy (IC) followed by CRT.

METHODS

We enrolled patients with potentially resectable localized EGAC (T3, T4aN0, or node-positive disease) in this open-label, single-arm, multicenter, Phase II trial between January 2020 and October 2022. Patients received three cycles of IC with trifluridine/tipiracil and oxaliplatin and then underwent concurrent CRT with weekly carboplatin and paclitaxel followed by surgery. The primary objective was to evaluate the pCR rate. The secondary objectives were to evaluate 2-year progression-free survival (PFS), 2-year overall survival (OS), and toxicities. Circulating tumor DNA (ctDNA) was measured at prespecified intervals to assess its correlation with clinical outcomes.

RESULTS

Of the 22 enrolled patients, 19 (86.4%) were male and 20 (90.9%) were Caucasian. The median age was 61 years, and 12 (54.5%) had their primary disease at the gastroesophageal junction. Twenty (90.9%) patients had T3 disease, and 15 (68.2%) had node-positive disease. Only two patients had pCRs, and an additional five had near pCRs. Since we could not meet our predefined pCR rate at the interim analysis, the study was closed. After a median follow-up of 15.8 months, 2-year OS and PFS were 43% and 41%, respectively. ctDNA clearance was associated with a significantly higher OS rate (p = 0.012) and PFS rate (p = 0.008). Nausea (59.1%) and fatigue (59.1%) were common treatment-related adverse events (AEs); nine (40.9%) patients had Grade 3 or higher AEs.

CONCLUSION

IC with trifluridine/tipiracil and oxaliplatin followed by CRT did not improve pCR rate in resectable EGAC compared to pCR from previous reports with CRT alone. We found a correlation between ctDNA clearance and improved survival, which merits further investigation.

CLINICAL TRIAL INFORMATION

NCT04097028.

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

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

Advances in radiotherapy in the treatment of esophageal cancer

Recent advancements in radiotherapy for esophageal cancer have significantly improved treatment outcomes and patient quality of life. Traditional radiotherapy techniques have been enhanced by the integration of advanced imaging and precision targeting technologies, such as intensity-modulated radiotherapy and proton therapy, which allow for more accurate tumor targeting while minimizing damage to surrounding healthy tissues. Additionally, combining radiotherapy with immunotherapy has shown promising results, leveraging the body's immune response to enhance the effectiveness of cancer treatment. Studies have also highlighted the benefits of neoadjuvant chemoradiation followed by surgical resection, which has been associated with improved overall survival rates compared to radiotherapy alone. These innovations are paving the way for more effective and personalized treatment strategies, offering new hope for patients with esophageal cancer.

FAPI-PET/CT guided radiotherapy for patients with esophageal cancer

BACKGROUND

Cancer associated fibroblasts have become a target of interest in different malignancies for positron emission tomography (PET) imaging, using positron emitter labelled fibroblast activation protein inhibitors (FAPI). New data underline the advanced imaging properties of FAPI-PET/CT for the staging of esophageal cancer compared to standard imaging. Potential benefits of FAPI-PET/CT in radiation therapy planning are the subject of this investigation.

METHODS

Ten patients with newly diagnosed esophageal cancer treated with radiochemotherapy (RCT) were retrospectively analyzed. All patients underwent [68Ga]OncoFAP-PET/CT in treatment position to facilitate radiation treatment planning. Six patients received neoadjuvant RCT as part of a trimodal therapy and four patients underwent definitive RCT. In five cases, restaging after initial treatment was performed with FAPI-PET/CT.

RESULTS

[68Ga]OncoFAP-PET/CT based imaging showed a high correlation with the endoscopic staging for initial imaging. In three cases, new sites of disease were unmasked, not visible in CT- and endosonographic staging. [68Ga]OncoFAP-PET/CT based RT delineation offered good definition of clinical target volumes, especially in retro-/paracardial areas and the gastroesophageal junction.

CONCLUSION

[68Ga]OncoFAP-PET/CT may aid and improve radiation treatment planning for patients with esophageal cancer.

CT-Derived Quantitative Image Features Predict Neoadjuvant Treatment Response in Adenocarcinoma of the Gastroesophageal Junction with High Accuracy

BACKGROUND

The purpose of this retrospective study was to evaluate the value of contrast-enhanced computed tomography (CE-CT) image features at baseline and after neoadjuvant chemotherapy in predicting histopathological response in patients with adenocarcinoma of the gastroesophageal junction (GEJ).

METHODS

A total of 105 patients with a diagnosis of adenocarcinoma of the GEJ were examined by CE-CT at baseline and preoperatively after neoadjuvant chemotherapy. All patients underwent surgical resection. Histopathological parameters and tumor regression grading according to Becker et al. were collected in 93 patients. Line profiles of the primary tumor area in baseline and preoperative CE-CT were generated using ImageJ. Maximum tumor density and tumor-to-wall density delta were calculated and correlated with the histopathological tumor response. In addition, tumor response was assessed according to standard RECIST measurements in all patients and by endoscopy in 72 patients.

RESULTS

Baseline and change in baseline to preoperative CE-CT parameters showed no significant differences between responders (Becker grade 1a, 1b) and non-responders (Becker grade 2, 3). After neoadjuvant therapy, responders and non-responders showed significant differences in maximum density and tumor-to-wall density delta values. Line profile measurements showed excellent inter-rater agreement. In comparison, neither RECIST nor endoscopy showed significant differences between these groups.

CONCLUSIONS

Posttreatment CE-CT can predict histopathological therapy response to neoadjuvant treatment in adenocarcinoma of GEJ patients with high accuracy and thus may improve patient management.

Phase I/II Trial of Perioperative Avelumab in Combination With Chemoradiation in the Treatment of Stage II/III Resectable Esophageal and Gastroesophageal Junction Cancer

BACKGROUND AND OBJECTIVES

Standard treatment of patients with stage II/III esophageal or gastroesophageal junction (E/GEJ) cancer involves neoadjuvant chemoradiation (nCRT), resection, and immunotherapy. Our trial evaluated the addition of perioperative avelumab to standard treatments.

METHODS

Patients with resectable E/GEJ cancers received avelumab with nCRT and adjuvant avelumab after resection. Primary endpoints for phase I and II portions were safety and pathologic complete response (pCR) rate, respectively. Secondary endpoints included recurrence-free survival (RFS), surgical complication prevalence, and R0 resection rate.

RESULTS

Twenty-two patients enrolled in the study. Median follow-up during data cutoff was 23.9 months. There were no dose-limiting toxicities during the run-in phase. Nineteen patients (86.4%) underwent resection with R0 resection rate of 78.9% and with pCR rate of 26%. Most common treatment-related adverse events (TRAE) were cytopenias from chemoradiation. Aside from one grade ≥ 3 avelumab-related hypersensitivity, no grade ≥ 3 avelumab TRAEs were seen. Median RFS was not reached, and 1-year RFS and overall survival were 71% and 81%, respectively. The study was terminated before full planned accrual due to standard practice change based on the CheckMate 577 trial.

CONCLUSIONS

The addition of perioperative avelumab to nCRT was tolerable and demonstrated promising outcomes.

A narrative review on advances in neoadjuvant immunotherapy for esophageal cancer: Molecular biomarkers and future directions

Esophageal cancer has a poor prognosis and survival rate due to its high incidence in Asia, lack of early symptoms and limited treatment options. In recent years, many clinical trials have demonstrated that immunotherapy has greatly improved the survival of patients with esophageal cancer. In addition, the combination of neoadjuvant immunotherapy with other popular therapeutic regimens has shown good efficacy and safety. In this review, we summarize the progress of clinical trials and some breakthroughs in neoadjuvant immunotherapy for esophageal cancer in recent years and suggest the possibility of multimodal neoadjuvant immunotherapy regimens, as well as directions for future development.

Optimizing neoadjuvant radiotherapy for locally advanced esophageal squamous cell carcinoma: a comprehensive review on the role of concomitant or sequential immune checkpoint inhibitors

Esophageal squamous cell carcinoma (ESCC) is a prevalent form of esophageal cancer with a poor prognosis despite advances in treatment. Combining immune checkpoint inhibitors (ICIs) with radiotherapy (RT) or chemoradiotherapy (CRT) has shown potential in enhancing treatment efficacy. We conducted a comprehensive review of clinical trials published between 2019 and 2024, sourced from PubMed, Scopus, and Embase databases. Studies included were prospective phase II trials that evaluated the combination of ICIs with neoadjuvant chemoradiotherapy (nCRT) in resectable locally advanced ESCC. Ten trials met the inclusion criteria. The review highlights various approaches in combining ICIs with CRT, including concurrent, induction, and consolidation therapy. Among the included trials, a significant proportion focused on concurrently administering ICIs with CRT, showing promising outcomes with high pathological complete response rates (pCR) and manageable toxicities. However, further research is needed to validate the efficacy of induction and consolidation therapies and determine optimal treatment protocols. The combination of ICIs and nCRT can potentially improve treatment responses and outcomes for patients with locally advanced ESCC. Despite recent encouraging findings, most trials were single-arm with small sample sizes, indicating the need for larger studies with longer follow-ups to assess survival outcomes comprehensively.

Current Standards and Controversies in Multidisciplinary Management of Locoregional Gastroesophageal Junction Tumors

PURPOSE OF REVIEW

There has been controversy in the management of gastroesophageal (GE) junction cancers with pre-operative chemoradiation and peri-operative chemotherapy as accepted practices. We aim to assess and compare the defining trials establishing current standards of care and discuss future directions seeking to further improve patient-centered outcomes in GE junction cancers.

RECENT FINDINGS

Over the last two decades, several large Phase III randomized trials have been conducted including GE junction cancers, showing superiority of 1) pre-operative chemoradiation over surgery (CROSS) and 2) peri-operative chemotherapy with FLOT over CROSS without radiotherapy (FLOT 4). While NEO-Aegis suggested equipoise between the CROSS vs. peri-operative chemotherapy, the recently presented ESOPEC trial demonstrated superiority of peri-operative FLOT versus CROSS in esophagus and GE junction adenocarcinomas. Based on the ESOPEC trial, peri-operative chemotherapy with FLOT appears to be a preferred regimen for patients with resectable GE junction adenocarcinomas in patients able to receive FLOT. There is evidence in support of other practices, such as induction chemotherapy, pre-operative chemoradiation, definitive chemoradiation for those not fitting ESOPEC criteria. Chemoradiation ± chemotherapy with non-operative intent represents a promising strategy for patients seeking organ preservation, and ongoing studies will better define its feasibility and long-term outcomes.

Induction chemotherapy plus chemoradiotherapy in esophageal cancer: long-term results and exploratory analyses of a randomized controlled trial

BACKGROUND

Previous results of our trial demonstrated that the addition of induction chemotherapy (IC) prior to definitive chemoradiotherapy (CRT) failed to significantly improve the response rate or 3-year survival in patients with locally advanced esophageal squamous cell carcinoma (ESCC). Here, we report long-term results and exploratory analyses to further evaluate the therapeutic value of IC.

METHODS

Patients with previously untreated, unresectable, stage II-IVA ESCC were randomly assigned to receive IC followed by CRT or CRT alone. The relationship between tumor response to IC and long-term survival was analyzed. Baseline tumor biopsies were collected for RNA-Seq to identify patients who may benefit from IC.

RESULTS

Eligible patients were randomized to either the IC + CRT group (n = 55) or the CRT group (n = 55). With a median follow-up of 74.9 months, the 5-year overall survival rate was 31.8% in the IC + CRT group and 29.1% in the CRT group (P =.675; HR, 0.91; 95% CI, 0.58-1.43). Similarly, no significant differences were identified in 5-year progression-free survival between groups (30.5% vs 25.5%, P =.508; HR, 0.86; 95% CI, 0.56-1.34). Patients who responded to IC had significantly better survival than nonresponders. A risk-score model incorporating 6 key genes to predict IC efficacy was also constructed.

CONCLUSIONS

Compared with definitive CRT alone, the addition of IC before CRT still failed to demonstrate superior survival in patients with unselected ESCC, based on long-term follow-up. However, because IC responders were associated with more favorable survival, potential molecular biomarkers were identified for selection of benefit population from IC.

CLINICAL TRIALS REGISTRATION

NCT02403531.

Report from the 25th Annual Western Canadian Gastrointestinal Cancer Consensus Conference on Gastric and Gastroesophageal Cancers, Winnipeg, Manitoba, 26-27 October 2023

The 25th Annual Western Canadian Gastrointestinal Cancer Consensus Conference (WCGCCC) was held in Winnipeg, Manitoba, on 26-27 October 2023. The WCGCCC is an interactive multidisciplinary conference that was attended by healthcare professionals from across Western Canada (British Columbia, Alberta, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; oncology nurses; pharmacists; and a family physician in oncology (FPO) participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of gastroesophageal cancers.

Evaluating Treatment Response in GEJ Adenocarcinoma: The Role of Pretherapeutic and Posttherapeutic Iodine Mapping

BACKGROUND

Neoadjuvant therapy regimens have significantly improved the prognosis of GEJ (gastroesophageal junction) cancer; however, there are a significant percentage of patients who benefit from earlier resection or adapted therapy regimens, and the true response rate can only be determined histopathologically. Methods that allow preoperative assessment of response are lacking.

PURPOSE

The purpose of this retrospective study is to assess the potential of pretherapeutic and posttherapeutic spectral CT iodine density (IoD) in predicting histopathological response to neoadjuvant chemotherapy in patients diagnosed with adenocarcinoma of the GEJ.

METHODS

In this retrospective cohort study, a total of 62 patients with GEJ carcinoma were studied. Patients received a multiphasic CT scan at diagnosis and preoperatively. Iodine-density maps were generated based on spectral CT data. All tumors were histopathologically analyzed, and the tumor regression grade (TRG) according to Becker et al ( Cancer . 2003;98:1521-1530) was determined. Two experienced radiologists blindly placed 5 defined ROIs in the tumor region of highest density, and the maximum value was used for further analysis. Iodine density was normalized to the aortic iodine uptake. In addition, tumor response was assessed according to standard RECIST measurement. After assessing interrater reliability, the correlation of IoD values with treatment response and with histopathologic TRG was evaluated.

RESULTS

The normalized ΔIoD (IoD at diagnosis - IoD after neoadjuvant treatment) and the normalized IoD after neoadjuvant treatment correlated significantly with the TRG. For the detection of responders and nonresponders, the receiver operating characteristic (ROC) curve for normalized ΔIoD yielded the highest area under the curve of 0.95 and achieved a sensitivity and specificity of 92.3% and 92.1%, respectively. Iodine density after neoadjuvant treatment achieved an area under the curve of 0.88 and a sensitivity and specificity of 86.8% and 84.6%, respectively (cutoff, 0.266). Iodine density at diagnosis and RECIST did not provide information to distinguish responders from nonresponders. Using the cutoff value for IoD after neoadjuvant treatment, a reliable classification of responders and nonresponders was achieved for both readers in a test set of 11 patients. Intraclass correlation coefficient revealed excellent interrater reliability (intraclass correlation coefficient, >0.9). Lastly, using the cutoff value for normalized ΔIoD as a definition for treatment response, a significantly longer survival of responders was shown.

CONCLUSIONS

Changes in IoD after neoadjuvant treatment of GEJ cancer may be a potential surrogate for therapy response.

Utility of Initial Tumor Reduction as a Prognostic Factor in Esophageal Squamous Cell Cancer Patients Undergoing Neoadjuvant Chemotherapy Followed by Surgery : A Retrospective Cohort Study

BACKGROUND

While a neoadjuvant chemotherapy regimen using docetaxel, cisplatin, and 5-fluorouracil (NAC-DCF) is considered the standard treatment for locally advanced esophageal cancer (EC) in Japan, a reliable marker for early prediction of treatment efficacy remains unclear. We investigated the utility of the tumor response after a first course of NAC-DCF as a post-surgery survival predictor in patients with EC.

METHODS

We enrolled 150 consecutive patients who underwent NAC-DCF followed by surgery for EC between September 2009 and January 2019. The initial tumor reduction (ITR), defined as the percentage decrease in the shorter diameter of the tumor after the first course of NAC-DCF, was evaluated using computed tomography. We analyzed the relationship between ITR, clinicopathological parameters, and survival.

RESULTS

The median ITR was 21.07% (range -11.45 to 50.13%). The optimal cut-off value for ITR for predicting prognosis was 10% (hazard ratio [HR] 3.30, 95% confidence interval [CI] 1.98-5.51), based on univariate logistic regression analyses for recurrence-free survival (RFS). Compared with patients with ITR <10%, patients with ITR ≥10% showed a significantly higher proportion of ypM0 (80.0% vs. 92.5%) and responders in terms of overall clinical response (50.0% vs. 80.8%). Multivariate analysis for RFS revealed that ypN2-3 (HR 2.78, 95% CI 1.67-4.62), non-response in terms of overall clinical response (HR 1.87, 95% CI 1.10-3.18), and ITR <10% (HR 2.48, 95% CI 1.42-4.32) were independent prognostic factors.

CONCLUSIONS

Tumor response after the first course of NAC-DCF may be a good predictor of survival in patients with EC who underwent NAC-DCF plus surgery.

The Role of Immunotherapy in the Management of Esophageal Cancer in Patients Treated with Neoadjuvant Chemoradiation: An Analysis of the National Cancer Database

BACKGROUND

The current National Comprehensive Cancer Network advises neoadjuvant chemoradiotherapy followed by surgery for locally advanced cases of esophageal cancer. The role of immunotherapy in this context is under heavy investigation.

METHODS

Patients with esophageal adenocarcinoma were identified in the National Cancer Database (NCDB) from 2004 to 2019. Three groups were generated as follows: (a) no immunotherapy, (b) neoadjuvant immunotherapy, and (c) adjuvant immunotherapy. Overall survival was evaluated using the Kaplan-Meier method and Cox proportional hazard analysis, adjusting for previously described risk factors for mortality.

RESULTS

Of the total 14,244 patients diagnosed with esophageal adenocarcinoma who received neoadjuvant chemoradiation, 14,065 patients did not receive immunotherapy, 110 received neoadjuvant immunotherapy, and 69 received adjuvant immunotherapy. When adjusting for established risk factors, adjuvant immunotherapy was associated with significantly improved survival compared to no immunotherapy and neoadjuvant immunotherapy during a median follow-up period of 35.2 months. No difference was noted among patients who received no immunotherapy vs. neoadjuvant immunotherapy in the same model.

CONCLUSIONS

In this retrospective analysis of the NCDB, receiving adjuvant immunotherapy offered a significant survival advantage compared to no immunotherapy and neoadjuvant immunotherapy in the treatment of esophageal adenocarcinoma. The addition of neoadjuvant immunotherapy to patients treated with neoadjuvant chemoradiation did not improve survival in this cohort. Further studies are warranted to investigate the long-term outcomes of immunotherapy in esophageal cancer.

Systematic Review of Hypofractionated Radiation Therapy for the Treatment of Oesophageal Squamous Cell Carcinoma and Oesophageal Adenocarcinoma

BACKGROUND AND AIM

There has been limited progress made in improving the suboptimal outcomes delivered by conventionally fractionated radiotherapy (RT) for oesophageal adenocarcinoma (OAC) and squamous cell carcinoma (OSCC). A greater biological effect may be achieved using hypofractionated RT (HFRT), though the toxicity, tolerability and efficacy of this approach in OAC and OSCC is uncertain.

METHODS

A systematic literature review was carried out in accordance with Preferred Reporting Items for Systematic Reviews guidance. Medline, EMBASE, PubMed, Cochrane, CINAHL, Scopus and Web of Science databases were searched for terms relating to HFRT (>2.4Gy per fraction) for OAC or OSCC. All relevant clinical studies published between January 2000 and April 2023 were included. Study quality was assessed using predefined criteria.

RESULTS

Ninety-six studies were screened and 20 subsequently included, together incorporating 1208 patients. Fourteen studies focussed on neoadjuvant or definitive treatment. These were predominantly retrospective (n = 10, 71%) though two (n = 2, 14%) early phase trials were identified. Most focussed on OSCC (n = 7, 47%) or mixed OSCC/OAC (n = 6, 43%) populations. Four (28.6%) included a conventionally fractionated chemoradiotherapy (CRT) comparator, against which median overall (mOS) and progression free survival outcomes from HFRT did not differ. Reported mOS for HFRT ranged between 29-36 months at 2.5-3.125Gy per fraction (total dose 50-60Gy) for OAC and OSCC combined. Toxicity and tolerability with HFRT was comparable with conventionally fractionated CRT up to, but not exceeding, 5Gy. Three (50%) of the six palliative-intent studies were early phase trials and most (n = 4, 67%) focussed on OAC and OSCC. Response rates with HFRT in the palliative setting were 63.6-88.0%.

CONCLUSION

These data provide evidence in OAC/OSCC for promising efficacy and an acceptable toxicity profile for moderately HFRT, alone or with concurrent chemotherapy. These data should prompt prospective, randomised comparisons of HFRT and conventionally fractionated CRT and single-modality RT schedules.

REGISTRATION DETAILS

PROSPERO; CRD42023457791.

Advances in diagnosis and management of cancer of the esophagus

Esophageal cancer is the seventh most common malignancy worldwide, with over 470 000 new cases diagnosed each year. Two distinct histological subtypes predominate, and should be considered biologically separate disease entities.1 These subtypes are esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC). Outcomes remain poor regardless of subtype, with most patients presenting with late stage disease.2 Novel strategies to improve early detection of the respective precursor lesions, squamous dysplasia, and Barrett's esophagus offer the potential to improve outcomes. The introduction of a limited number of biologic agents, as well as immune checkpoint inhibitors, is resulting in improvements in the systemic treatment of locally advanced and metastatic esophageal cancer. These developments, coupled with improvements in minimally invasive surgical and endoscopic treatment approaches, as well as adaptive and precision radiotherapy technologies, offer the potential to improve outcomes still further. This review summarizes the latest advances in the diagnosis and management of esophageal cancer, and the developments in understanding of the biology of this disease.

Esophagogastric Cancer: The Current Role of Radiation Therapy

Radiation therapy is an effective treatment modality in the management of patients with esophageal cancer regardless of tumor location (proximal, middle, or distal esophagus) or histology (squamous cell vs adenocarcinoma). The addition of neoadjuvant CRT to surgery in patients who are surgical candidates has consistently shown a benefit in terms of locoregional recurrence, pathologic downstaging, and overall survival. For patients who are not surgical candidates, CRT has a role as definitive treatment.

Neoadjuvant nivolumab or nivolumab plus LAG-3 inhibitor relatlimab in resectable esophageal/gastroesophageal junction cancer: a phase Ib trial and ctDNA analyses

Gastroesophageal cancer dynamics and drivers of clinical responses with immune checkpoint inhibitors (ICI) remain poorly understood. Potential synergistic activity of dual programmed cell death protein 1 (PD-1) and lymphocyte-activation gene 3 (LAG-3) inhibition may help improve immunotherapy responses for these tumors. We report a phase Ib trial that evaluated neoadjuvant nivolumab (Arm A, n = 16) or nivolumab-relatlimab (Arm B, n = 16) in combination with chemoradiotherapy in 32 patients with resectable stage II/stage III gastroesophageal cancer together with an in-depth evaluation of pathological, molecular and functional immune responses. Primary endpoint was safety; the secondary endpoint was feasibility; exploratory endpoints included pathological complete (pCR) and major pathological response (MPR), recurrence-free survival (RFS) and overall survival (OS). The study met its primary safety endpoint in Arm A, although Arm B required modification to mitigate toxicity. pCR and MPR rates were 40% and 53.5% for Arm A and 21.4% and 57.1% for Arm B. Most common adverse events were fatigue, nausea, thrombocytopenia and dermatitis. Overall, 2-year RFS and OS rates were 72.5% and 82.6%, respectively. Higher baseline programmed cell death ligand 1 (PD-L1) and LAG-3 expression were associated with deeper pathological responses. Exploratory analyses of circulating tumor DNA (ctDNA) showed that patients with undetectable ctDNA post-ICI induction, preoperatively and postoperatively had a significantly longer RFS and OS; ctDNA clearance was reflective of neoantigen-specific T cell responses. Our findings provide insights into the safety profile of combined PD-1 and LAG-3 blockade in gastroesophageal cancer and highlight the potential of ctDNA analysis to dynamically assess systemic tumor burden during neoadjuvant ICI that may open a therapeutic window for future intervention. ClinicalTrials.gov registration: NCT03044613 .

Pathologic complete response in patients with esophageal cancer receiving neoadjuvant chemotherapy or chemoradiation: A systematic review and meta-analysis

BACKGROUND

Neoadjuvant chemoradiation and chemotherapy are recommended for the treatment of nonmetastatic esophageal cancer. The benefit of neoadjuvant treatment is mostly limited to patients who exhibit pathologic complete response (pCR). Existing estimates of pCR rates among patients receiving neoadjuvant therapy have not been synthesized and lack precision.

METHODS

We conducted an independently funded systematic review and meta-analysis (PROSPERO CRD42023397402) of pCR rates among patients diagnosed with esophageal cancer treated with neoadjuvant chemo(radiation). Studies were identified from Medline, EMBASE, and CENTRAL database searches. Eligible studies included trials published from 1992 to 2022 that focused on nonmetastatic esophageal cancer, including the gastroesophageal junction. Histology-specific pooled pCR prevalence was determined using the Freeman-Tukey transformation and a random effects model.

RESULTS

After eligibility assessment, 84 studies with 6451 patients were included. The pooled prevalence of pCR after neoadjuvant chemotherapy in squamous cell carcinomas was 9% (95% CI: 6%-14%), ranging from 0% to 32%. The pooled prevalence of pCR after neoadjuvant chemoradiation in squamous cell carcinomas was 32% (95% CI: 26%-39%), ranging from 8% to 66%. For adenocarcinoma, the pooled prevalence of pCR was 6% (95% CI: 1%-12%) after neoadjuvant chemotherapy, and 22% (18%-26%) after neoadjuvant chemoradiation.

CONCLUSIONS

Under one-third of patients with esophageal cancer who receive neoadjuvant chemo(radiation) experience pCR. Patients diagnosed with squamous cell carcinomas had higher rates of pCR than those with adenocarcinomas. As pCR represents an increasingly utilized endpoint in neoadjuvant trials, these estimates of pooled pCR rates may serve as an important benchmark for future trial design.

Neoadjuvant chemotherapy for early-stage colon cancer

Surgery with or without adjuvant chemotherapy is the standard treatment for early-stage colon cancer. However, evidence has recently emerged for neoadjuvant chemotherapy, with the results of randomised clinical trials sparking debates within multidisciplinary teams and splitting the gastrointestinal oncology community. Further to a systematic search of the literature, we provide a thorough and in-depth analysis of the findings from these trials, highlighting the advantages and disadvantages of neoadjuvant chemotherapy. We conclude that, while there is a potential value of moving systemic therapy from the post-operative to the pre-operative setting, the available evidence does not justify a shift in the treatment paradigm of early-stage colon cancer, and surgery with or without adjuvant chemotherapy should remain the standard approach for these patients.

Current and future on definitive concurrent chemoradiotherapy for inoperable locally advanced esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is an aggressive and fatal disease that is usually diagnosed when the chances for surgical intervention has been missed. Definitive concurrent chemoradiotherapy (dCRT) is the first choice of treatment for inoperable locally advanced esophageal squamous cell carcinoma (LA-ESCC). Nevertheless, the local recurrence rate for esophageal cancer patients undergoing dCRT remains high at 40-60%, with a 5-year overall survival rate of solely 10-30%. Immunotherapy in combination with dCRT is a promising treatment for inoperable LA-ESCC, for that improved long-term survival is expected. The present review provides a comprehensive overview of the evolutionary trajectory of dCRT for LA-ESCC, delineates notable relevant clinical studies, addresses unresolved concerns regarding the combination of dCRT with immunotherapy, and highlights promising directions for future research. When dCRT is combined with immunotherapy, the following aspects should be carefully explored in the future studies, including the optimal irradiation dose, segmentation scheme, radiotherapy technique, timing, sequence and duration of radiotherapy, and the selection of chemotherapeutic and immunologic drugs. In addition, further investigations on the mechanisms of how dCRT combined with immunotherapy exerts synergistic anti-tumor effects and molecular biomarkers ensuring precise screening of ESCC patients are needed.

The Evolving Landscape of Neoadjuvant Immunotherapy in Gastroesophageal Cancer

Despite advances in treatment strategies and surgical approaches in recent years, improving survival outcomes in esophagogastric cancer (EGC) patients treated with curative intent remains a significant area of unmet need. The recent emergence of adjuvant immunotherapy as the standard of care for resected EGC demonstrates the impact of immunotherapy in improving recurrence-free survival. Neoadjuvant and perioperative immunotherapies represent another promising approach with potential advantages over adjuvant therapy. Despite the promising results of early neoadjuvant immunotherapy studies, there are several challenges and future research needs. The optimal timing, duration and number of doses in relation to surgery and the optimal combination of immunotherapies are still unclear. In addition, rigorous correlative studies need to be performed to identify biomarkers for patient selection and treatment response prediction to maximize the benefits of neoadjuvant immunotherapy. In this review, we provide a concise summary of the current standard of care for resectable EGC and discuss the rationale for the use of immune checkpoint inhibitors in this setting and the pre-clinical and early clinical data of these novel therapies. Finally, we will examine the potential role and future direction of immunotherapy in the treatment paradigm and the perceived challenges and opportunities that lay ahead.

The Society of Thoracic Surgeons/American Society for Radiation Oncology Updated Clinical Practice Guidelines on Multimodality Therapy for Locally Advanced Cancer of the Esophagus or Gastroesophageal Junction

Outcomes for patients with esophageal cancer have improved over the last decade with the implementation of multimodality therapy. There are currently no comprehensive guidelines addressing multidisciplinary management of esophageal cancer that have incorporated the input of surgeons, radiation oncologists, and medical oncologists. To address the need for multidisciplinary input in the management of esophageal cancer and to meet current best practices for clinical practice guidelines, the current guidelines were created as a collaboration between The Society of Thoracic Surgeons (STS), American Society for Radiation Oncology (ASTRO), and the American Society of Clinical Oncology (ASCO). Physician representatives chose 8 key clinical questions pertinent to the care of patients with locally advanced, resectable thoracic esophageal cancer (excluding cervical location). A comprehensive literature review was performed identifying 227 articles that met the inclusion criteria covering the use of induction chemotherapy, chemotherapy vs chemoradiotherapy before surgery, optimal radiation dose, the value of esophagectomy, timing of esophagectomy, the approach and extent of lymphadenectomy, the use of minimally invasive esophagectomy, and the value of adjuvant therapy after resection. The relevant data were reviewed and voted on by the panel with 80% of the authors, with 75% agreement on class and level of evidence. These data were then complied into the guidelines document.

The Society of Thoracic Surgeons/American Society for Radiation Oncology Updated Clinical Practice Guidelines on Multimodality Therapy for Locally Advanced Cancer of the Esophagus or Gastroesophageal Junction

Outcomes for patients with esophageal cancer have improved over the last decade with the implementation of multimodality therapy. There are currently no comprehensive guidelines addressing multidisciplinary management of esophageal cancer that have incorporated the input of surgeons, radiation oncologists, and medical oncologists. To address the need for multidisciplinary input in the management of esophageal cancer and to meet current best practices for clinical practice guidelines, the current guidelines were created as a collaboration between The Society of Thoracic Surgeons (STS), American Society for Radiation Oncology (ASTRO), and the American Society of Clinical Oncology (ASCO). Physician representatives chose 8 key clinical questions pertinent to the care of patients with locally advanced, resectable thoracic esophageal cancer (excluding cervical location). A comprehensive literature review was performed identifying 227 articles that met the inclusion criteria covering the use of induction chemotherapy, chemotherapy vs chemoradiotherapy before surgery, optimal radiation dose, the value of esophagectomy, timing of esophagectomy, the approach and extent of lymphadenectomy, the use of minimally invasive esophagectomy, and the value of adjuvant therapy after resection. The relevant data were reviewed and voted on by the panel with 80% of the authors, with 75% agreement on class and level of evidence. These data were then complied into the guidelines document.

Opportunities and challenges in combining immunotherapy and radiotherapy in esophageal cancer

BACKGROUND

Immunotherapy has shown promise in the treatment of esophageal cancer, but using it alone only benefits a small number of patients. Most patients either do not have a significant response or develop secondary drug resistance. The combination of radiotherapy and immunotherapy appears to be a promising approach to treating esophageal cancer.

PURPOSE

We reviewed milestone clinical trials of radiotherapy combined with immunotherapy for esophageal cancer. We then discussed potential biomarkers for radiotherapy combined with immunotherapy, including programmed cell death-ligand 1 (PD-L1) status, tumor mutation burden (TMB), tumor-infiltrating lymphocytes, ct-DNA, imaging biomarkers, and clinical factors. Furthermore, we emphasize the key mechanisms of radiation therapy-induced immune stimulation and immune suppression in order to propose strategies for overcoming immune resistance in radiation therapy (RT). Lastly, we discussed the emerging role of low-dose radiotherapy (LDRT) , which has become a promising approach to overcome the limitations of high-dose radiotherapy.

CONCLUSION

Radiotherapy can be considered a triggering factor for systemic anti-tumor immune response and, with the assistance of immunotherapy, can serve as a systemic treatment option and potentially become the standard treatment for cancer patients.

Change in stage after neoadjuvant chemoradiation is associated with survival in patients with esophageal cancer

BACKGROUND

The aim of this study was to determine if change in stage after neoadjuvant chemoradiation (CRT) was associated with improved survival in esophageal cancer using a national database.

METHODS

Using the National Cancer Database, patients with non-metastatic, resectable esophageal cancer who received neoadjuvant CRT and surgery were identified. Comparing clinical to the pathologic stage, change in stage was classified as pathologic complete response (pCR), downstaged, same-staged, or upstaged. Univariable and multivariable Cox regression models were used to identify factors associated with survival.

RESULTS

A total of 7745 patients were identified. The median overall survival (OS) was 34.9 months. Median OS was 60.3 months if pCR, 39.1 months if downstaged, 28.3 months if same-staged, and 23.4 months if upstaged (p < 0.0001). On multivariable analysis, pCR was associated with improved OS compared to the other groups (downstaged: hazard ratio [HR]: 1.32 [95% confidence interval [CI]: 1.18-1.46]; same-staged: HR: 1.89 [95% CI: 1.68-2.13]; upstaged: HR: 2.54 [95% CI: 2.25-2.86]; all p < 0.0001).

CONCLUSIONS

In this large database study, change in stage after neoadjuvant CRT was strongly associated with survival for patients with non-metastatic, resectable esophageal cancer. There was a significant stepwise decline in survival, in descending order of pCR, downstaged tumor, same-staged tumor, and upstaged tumor.

MiR-199a-5p Decreases Esophageal Cancer Cell Proliferation Partially through Repression of Jun-B

MicroRNA (miR)-199a-5p has been shown to function as a tumor suppressor in some malignancies but its role in esophageal cancer is poorly understood. To further explore its role in esophageal cancer, we sought to investigate the interaction between miR-199a-5p and Jun-B, an important component of the AP1 transcription factor, which contains a potential binding site for miR-199a-5p in its mRNA. We found that levels of miR-199a-5p are reduced in both human esophageal cancer specimens and in multiple esophageal cancer cell lines compared to esophageal epithelial cells. Jun-B expression is correspondingly elevated in these tumor specimens and in several cell lines compared to esophageal epithelial cells. Jun-B mRNA expression and stability, as well as protein expression, are markedly decreased following miR-199a-5p overexpression. A direct interaction between miR-199a-5p and Jun-B mRNA was confirmed by a biotinylated RNA-pull down assay and luciferase reporter constructs. Either forced expression of miR-199a-5p or Jun-B silencing led to a significant decrease in cellular proliferation as well as in AP-1 promoter activity. Our results provide evidence that miR-199a-5p functions as a tumor suppressor in esophageal cancer cells by regulating cellular proliferation, partially through repression of Jun B.

Induction Fluorouracil-Based Chemotherapy and PET-Adapted Consolidation Chemoradiation with Esophagectomy for High-Risk Gastroesophageal Adenocarcinoma

Background: Neoadjuvant chemoradiation with esophagectomy is standard management for locally advanced esophageal adenocarcinoma. Induction chemotherapy with a tailored approach to chemoradiation based on metabolic response to therapy on PET was explored as an alternative strategy in the CALGB 80803 trial. We sought to describe real-world institutional experience implementing this approach outside of a clinical trial. Methods: Patients who were treated with induction fluorouracil-leucovorin-oxaliplatin (FOLFOX) or fluorouracil-leucovorin-oxaliplatin-docetaxel (FLOT) with tailored chemoradiation based on PET response and subsequent esophagectomy were identified from a prospectively maintained database. Primary outcomes were pathologic complete response (pCR) and overall survival (OS) following completion of all therapy. Results: There were 35 patients who completed induction chemotherapy, chemoradiation, and esophagectomy. Thirty-three completed restaging PET following induction chemotherapy with metabolic response seen in 76% (n = 25/33). The pCR rate was 31% (n = 11/35) and the ypN0 rate was 71% (n = 25/35). Among the patients who demonstrated metabolic response to induction FOLFOX/FLOT and subsequently continued fluorouracil-based chemoradiation, the pCR rate was 39% (n = 9/23). The rate of pathologically negative lymph nodes in this group was high (n = 19/23, 83%) with 100% R0 resection rate (n = 23/23). With the median follow-up of 43 months, the median OS was not reached for this group and was significantly longer than the OS for the remainder of the cohort (p = 0.027, p = 0.046 adjusted for clinical stage). Conclusions: Induction FOLFOX/FLOT chemotherapy with evaluation of sensitivity via metabolic response and tailored chemoradiation seems to lead to high pCR and ypN0 rates in high-risk patients with adenocarcinoma of the esophagus and GE junction. This approach in clinical practice seems to recapitulate encouraging results in clinical trials.

Durvalumab and PET-Directed Chemoradiation in Locally Advanced Esophageal Adenocarcinoma: A Phase Ib/II Study

OBJECTIVE

To determine the safety and efficacy of adding the anti-PD-L1 antibody durvalumab to induction FOLFOX and preoperative chemotherapy in locally advanced esophageal adenocarcinoma.

BACKGROUND

Neoadjuvant induction FOLFOX followed by positron emission tomography (PET) directed chemoradiation has demonstrated improved survival for esophageal adenocarcinoma. There is clear benefit now for the addition of immune checkpoint inhibitors both in early and advanced stage disease. Given these results we investigated the safety and efficacy of adding durvalumab to induction FOLFOX and preoperative chemoradiotherapy.

METHODS

Patients with locally advanced resectable esophageal/gastroesophageal junction adenocarcinoma received PET-directed chemoradiation with durvalumab before esophagectomy. Patients who had R0 resections received adjuvant durvalumab 1500 mg every 4 weeks for 6 treatments. The primary endpoint of the study was pathologic complete response.

RESULTS

We enrolled 36 patients, 33 of whom completed all preoperative treatment and underwent surgery. Preoperative treatment was well tolerated, with no delays to surgery nor new safety signals. Pathologic complete response was identified in 8 [22% (1-sided 90% lower bound: 13.3%)] patients with major pathologic response in 22 [61% (1-sided 90% lower bound: 50%)] patients. Twelve and 24-month overall survival was 92% and 85%, respectively.

CONCLUSIONS

The addition of durvalumab to induction FOLFOX and PET-directed chemoradiotherapy before surgery is safe, with a high rate of pathologic response, as well as encouraging survival data.

Neoadjuvant and adjuvant therapy in esophageal cancer

Esophageal cancer is an aggressive malignancy that carries a high mortality rate. The treatment of locally advanced resectable esophageal cancer requires a multimodal approach involving chemotherapy, radiation therapy, and surgical resection. Optimal treatment combinations and sequences for squamous cell carcinoma (SCC) versus adenocarcinoma (AC) histological subtypes are still being determined. For very early stage esophageal cancers, endoscopic therapies or surgical resection without chemotherapy and radiation are preferred. Neoadjuvant chemoradiation followed by surgical resection has been the standard in locally advanced resectable esophageal cancer based on the landmark CROSS trial. Definitive chemoradiation is recommended for patients who are not surgical candidates or decline surgery. Perioperative chemotherapy without radiation can be considered for lower esophageal AC and gastroesophageal (GE)-junction AC based on landmark MAGIC and FLOT4 trials. Additional trials are underway to compare preoperative chemoradiation to perioperative chemotherapy in esophageal and GE-junction ACs. Thus far, targeted therapies against vascular endothelial growth factor (VEGF) and human epidermal growth factor receptor 2 (HER2) have not been successful in the neoadjuvant/adjuvant setting. The roll of immunotherapy in perioperative/adjuvant setting is promising. Based on the CheckMate 577 trial, adjuvant nivolumab should be considered for all patients following neoadjuvant chemoradiation and R0 resection with residual pathologic disease. Additional trials involving various immunotherapy agents are underway.

Interpretation of Tumor Response Grade following Preoperative Therapy for Gastric Cancer: An Overview

Gastric cancer is among the top five causes of cancer-related death worldwide. Preoperative chemotherapy has been established as an option in patients with locally advanced gastric cancer. However, chemotherapy yields variable results, owing to the cellular and molecular heterogeneity of this disease. Identifying patients who did or did not respond to preoperative therapy can allow clinicians to alter treatment modalities and provide important information related to prognostication. A pathologic response to preoperative therapies, called the Tumor Response Grade (TRG), has been evaluated to quantify treatment response. Multiple systems for TRG have been established. However, the literature has demonstrated inconsistent results for TRG systems and prognosis, possibly due to variability in interpretation of tumor response between systems and interobserver variability. Radiographic responses to preoperative therapies using RECIST 1.1 criteria and endoscopically assessed tumor response have demonstrated association with survival; however, their use in gastric cancer remains challenging given the inability to accurately and consistently identify and measure the tumor, especially in the setting of neoadjuvant therapy, where treatment-related changes can obscure the gastric wall layers. While the response to preoperative therapies with positron emission tomography (PET) has shown promising results in esophageal and esophagogastric junction (EGJ) malignancies, its role in gastric cancer is still under investigation. This review is focused on summarizing the available literature related to evaluating TRG in gastric cancer, as well as providing a brief overview of the use of radiographic and endoscopic methods to assess response to preoperative therapies. Lastly, we outline future directions regarding the use of a universal TRG system to guide care and assist with prognosis.

Efficacy of early PET-CT directed switch to carboplatin and paclitaxel based definitive chemoradiotherapy in patients with oesophageal cancer who have a poor early response to induction cisplatin and capecitabine in the UK: a multi-centre randomised controlled phase II trial

Background

The utility of early metabolic response assessment to guide selection of the systemic component of definitive chemoradiotherapy (dCRT) for oesophageal cancer is uncertain.

Methods

In this multi-centre, randomised, open-label, phase II substudy of the radiotherapy dose-escalation SCOPE2 trial we evaluated the role of ¹⁸F-Fluorodeoxyglucose positron emission tomography (PET) at day 14 of cycle 1 of three-weekly induction cis/cap (cisplatin (60 mg/m²)/capecitabine (625 mg/m² days 1-21)) in patients with oesophageal squamous cell carcinoma (OSCC) or adenocarcinoma (OAC). Non-responders, who had a less than 35% reduction in maximum standardised uptake value (SUV_max) from pre-treatment baseline, were randomly assigned to continue cis/cap or switch to car/pac (carboplatin AUC 5/paclitaxel 175 mg/m²) for a further induction cycle, then concurrently with radiotherapy over 25 fractions. Responders continued cis/cap for the duration of treatment. All patients (including responders) were randomised to standard (50Gy) or high (60Gy) dose radiation as part of the main study. Primary endpoint for the substudy was treatment failure-free survival (TFFS) at week 24. The trial was registered with International Standard Randomized Controlled Trial Number 97125464 and ClinicalTrials.govNCT02741856.

Findings

This substudy was closed on 1st August 2021 by the Independent Data Monitoring Committee on the grounds of futility and possible harm. To this point from 22nd November 2016, 103 patients from 16 UK centres had participated in the PET-CT substudy; 63 (61.2%; 52/83 OSCC, 11/20 OAC) of whom were non-responders. Of these, 31 were randomised to car/pac and 32 to remain on cis/cap. All patients were followed up until at least 24 weeks, at which point in OSCC both TFFS (25/27 (92.6%) vs 17/25 (68%); p = 0.028) and overall survival (42.5 vs. 20.4 months, adjusted HR 0.36; p = 0.018) favoured cis/cap over car/pac. There was a trend towards worse survival in OSCC + OAC cis/cap responders (33.6 months; 95%CI 23.1-nr) vs. non-responders (42.5 (95%CI 27.0-nr) months; HR = 1.43; 95%CI 0.67-3.08; p = 0.35).

Interpretation

In OSCC, early metabolic response assessment is not prognostic for TFFS or overall survival and should not be used to personalise systemic therapy in patients receiving dCRT.

Funding

Cancer Research UK.

A Review of Advances in Radiotherapy in the Setting of Esophageal Cancers

Esophageal cancer is the eighth most common cancer worldwide and is the sixth most common cause of cancer-related mortality. The paradigm has shifted to include a multimodality approach with surgery, chemotherapy, targeted therapy (including immunotherapy), and radiation therapy. Advances in radiotherapy through techniques such as intensity modulated radiotherapy and proton beam therapy have allowed for the more dose homogeneity and improved organ sparing. In addition, recent studies of targeted therapies and predictive approaches in patients with locally advanced disease provide clinicians with new approaches to modify multimodality treatment to improve clinical outcomes.

Pre-operative chemoradiotherapy with or without induction chemotherapy for operable locally-advanced esophageal cancer

Background

For patients with operable locally advanced esophageal carcinoma (LA-EC), we hypothesized that pre-operative induction chemotherapy followed by chemoradiotherapy (IC-CRT) would improve progression-free survival (PFS) and overall survival (OS) when compared to chemoradiotherapy (CRT).

Methods

This was a single institution retrospective cohort study including patients with LA-EC who received preoperative-intent IC-CRT vs. CRT between 2013-2019. The Kaplan-Meier method was used to estimate OS and PFS. Cox proportional hazards regression was used to assess for variables associated with survival. The impact of treatment group on pathologic response was assessed by chi-square.

Results

Ninty-five patients were included for analysis (IC-CRT n=59; CRT n=36) and the median follow-up was 37.7 months (IQR: 16.8-56.1). There was no difference in median PFS or OS for IC-CRT or CRT, 22 months (95% CI: 12-59) vs. 32 months (95% CI: 10-57) (P=0.64) and 39 months (95% CI: 23-not reached) vs. 56.5 months (95% CI: 38-not reached) (P=0.36), respectively. Amongst the subset of patients with adenocarcinoma histology, there was no difference in median PFS or OS, nor was there when analyses were further restricted to those who received ≥3 cycles of induction 5-fluorouracil and platinum, or for those who underwent esophagectomy. Pathologic complete response occurred in 45% vs. 29% (P=0.24) and N-stage regression occurred in 72% vs. 58% (P=0.28) of patients in the IC-CRT and CRT cohorts, respectively. Distant metastasis occurred in 44% of patients in each treatment cohort.

Conclusions

For patients with LA-EC, preoperative-intent IC-CRT was not associated with improved PFS or OS when compared with CRT.

Radiotherapy combined with immune checkpoint inhibitors in locally advanced/metastatic esophageal squamous cell carcinoma: clinical trials, efficacy and future directions

Esophageal squamous cell carcinoma (ESCC) is a common malignancy worldwide and often diagnosed at advanced stages with poor prognosis. Combination of radiotherapy and immunotherapy seems to be a promising approach for treating ESCC. This comprehensive review article summarizes the current state of combination of radiotherapy and immunotherapy in locally advanced/metastatic ESCC, delineates the clinical trials that merit attention, and outlines unresolved issues and future research directions in this field. The clinical trial findings suggest that radio-immunotherapy combination may improve tumor response and overall survival with manageable side effects, highlighting the importance of patient selection and the necessity for further research to optimize treatment strategies. Issues such as irradiation dosage, fractionation regimen, irradiation site and technique of radiotherapy, as well as the timing, sequence and duration of combination therapy will all affect treatment outcomes, justifying further in-depth investigation.

Clinical Utility of 18F-2-Fluoro-deoxy-d-glucose PET Imaging in Locally Advanced Esophageal/Gastroesophageal Junction Adenocarcinoma

Esophageal adenocarcinoma, including adenocarcinoma of the gastroesophageal junction, is uncommon in the United States, but is associated with a rising incidence in young adults, and has a traditionally poor prognosis. Despite the incremental benefits that have been made with multimodality approaches to locally advanced disease, most patients will go on to develop metastatic disease, and long-term outcomes remain suboptimal. Over the last decade, PET-CT has emerged as a key tool in the management of this disease, with several prospective and retrospective studies evaluating its role in this disease. Herein, we review the key data pertaining to the use of PET-CT in the management of locally advanced esophageal and GEJ adenocarcinoma, with a focus on staging, prognostication, PET-CT adapted therapy in the neoadjuvant setting, and surveillance.

Risk stratification of oesophageal squamous cell carcinoma using change in total lesion glycolysis and number of PET-positive lymph nodes

BACKGROUND

The efficacy of neoadjuvant chemotherapy (NACT) correlates with patient survival in oesophageal squamous cell carcinoma (OSCC), but optimal evaluation of the treatment response based on PET-CT parameters has not been established.

METHODS

We analysed 226 OSCC patients who underwent PET-CT before and after NACT followed by surgery. We assessed SUVmax, metabolic tumour volume (MTV), and total lesion glycolysis (TLG) for the primary tumour and the number of PET-positive lymph nodes before and after NACT to predict patient survival.

RESULTS

In a stepwise analysis, we defined 60%, 80%, and 80% as the optimal cut-off values for SUVmax, MTV, and TLG reduction, respectively, to distinguish responders and non-responders to NACT. In the ROC analysis, the TLG reduction rate was the best predictor of recurrence among PET-CT parameters. The TLG responders achieved significantly more favourable prognoses than non-responders (2-year progression-free survival [PFS] rate: 64.1% vs. 38.5%; P = 0.0001). TLG reduction rate (HR 2.58; 95% CI 1.16-5.73) and the number of PET-positive lymph nodes after NACT (HR 1.79; 95% CI 1.04-3.08) were significant independent prognostic factors.

CONCLUSIONS

TLG reduction is the best predictor of prognosis. Preoperative PET-CT evaluation of both the primary tumour and lymph nodes could accurately stratify risk in OSCC patients.

Improving outcomes in patients with oesophageal cancer

The care of patients with oesophageal cancer or of individuals who have an elevated risk of oesophageal cancer has changed dramatically. The epidemiology of squamous cell and adenocarcinoma of the oesophagus has diverged over the past several decades, with a marked increase in incidence only for oesophageal adenocarcinoma. Only in the past decade, however, have molecular features that distinguish these two forms of the disease been identified. This advance has the potential to improve screening for oesophageal cancers through the development of novel minimally invasive diagnostic technologies predicated on cancer-specific genomic or epigenetic alterations. Surgical techniques have also evolved towards less invasive approaches associated with less morbidity, without compromising oncological outcomes. With improvements in multidisciplinary care, advances in radiotherapy and new tools to detect minimal residual disease, certain patients may no longer even require surgical tumour resection. However, perhaps the most anticipated advance in the treatment of patients with oesophageal cancer is the advent of immune-checkpoint inhibitors, which harness and enhance the host immune response against cancer. In this Review, we discuss all these advances in the management of oesophageal cancer, representing only the beginning of a transformation in our quest to improve patient outcomes.

Metabolic tumour and nodal response to neoadjuvant chemotherapy on FDG PET-CT as a predictor of pathological response and survival in patients with oesophageal adenocarcinoma

OBJECTIVES

2-deoxy-2[¹⁸F]Fluoro-D-glucose (FDG) PET-CT has an emerging role in assessing response to neoadjuvant therapy in oesophageal cancer. This study evaluated FDG PET-CT in predicting pathological tumour response (pTR), pathological nodal response (pNR) and survival.

METHODS

Cohort study of 75 patients with oesophageal or oesophago-gastric junction (GOJ) adenocarcinoma treated with neoadjuvant chemotherapy then surgery at Guy's and St Thomas' NHS Foundation Trust, London (2017-2020). Standardised uptake value (SUV) metrics on pre- and post-treatment FDG PET-CT in the primary tumour (mTR) and loco-regional lymph nodes (mNR) were derived. Optimum SUV_max thresholds for predicting pathological response were identified using receiver operating characteristic analysis. Predictive accuracy was compared to PERCIST (30% SUV_max reduction) and MUNICON (35%) criteria. Survival was assessed using Cox regression.

RESULTS

Optimum tumour SUV_max decrease for predicting pTR was 51.2%. A 50% cut-off predicted pTR with 73.5% sensitivity, 69.2% specificity and greater accuracy than PERCIST or MUNICON (area under the curve [AUC] 0.714, PERCIST 0.631, MUNICON 0.659). Using a 30% SUV_max threshold, mNR predicted pNR with high sensitivity but low specificity (AUC 0.749, sensitivity 92.6%, specificity 57.1%, p = 0.010). pTR, mTR, pNR and mNR were independent predictive factors for survival (pTR hazard ratio [HR] 0.10 95% confidence interval [CI] 0.03-0.34; mTR HR 0.17 95% CI 0.06-0.48; pNR HR 0.17 95% CI 0.06-0.54; mNR HR 0.13 95% CI 0.02-0.66).

CONCLUSIONS

Metabolic tumour and nodal response predicted pTR and pNR, respectively, in patients with oesophageal or GOJ adenocarcinoma. However, currently utilised response criteria may not be optimal. pTR, mTR, pNR and mNR were independent predictors of survival.

KEY POINTS

• FDG PET-CT has an emerging role in evaluating response to neoadjuvant therapy in patients with oesophageal cancer. • Prospective cohort study demonstrated that metabolic response in the primary tumour and lymph nodes was predictive of pathological response in a cohort of patients with adenocarcinoma of the oesophagus or oesophago-gastric junction treated with neoadjuvant chemotherapy followed by surgical resection. • Patients who demonstrated a response to neoadjuvant chemotherapy in the primary tumour or lymph nodes on FDG PET-CT demonstrated better survival and reduced rates of tumour recurrence.

Biology-Guided Radiation Therapy

Biology-guided radiation therapy is an emerging field whereby delivery of external beam radiotherapy incorporates biological/molecular imaging to inform radiation treatment. At present, there is evidence for the use of functional imaging such as PET to evaluate treatment response in patients both during and after radiation treatment as well as to provide a method of adapting or selecting patient-specific treatments. Examples in thoracic, gastrointestinal, and hematologic malignancies are provided. Improvements in PET metrics, thresholds, and novel radiotracers will further move this novel field forward.

Esophageal cancer: Is the CROSS strategy ready for history books?

The CROSS trial group deserves enormous credit for completing a well-powered randomized trial that has established the CROSS strategy as a standard of care for patients with potentially resectable esophageal cancer. However, the 10-year results are rather disappointing with only 38% of all patients treated with the CROSS strategy cured compared with approximately 25% who had surgery alone. Another standard, perioperative chemotherapy has produced similar disappointing results as the CROSS strategy. Although many of us are consumed by the question as to which option is better for our patients, we conclude that both strategies produce only marginal benefits. We should have better treatment options. The timing may be opportune to reflect on how to develop novel and rational strategies rather than propagate the historical empiric approaches.