Role of surgical resection in complete responders on FDG-PET after chemoradiotherapy for locally advanced esophageal squamous cell carcinoma

Could 18-FDG PET-CT Radiomic Features Predict the Locoregional Progression-Free Survival in Inoperable or Unresectable Oesophageal Cancer?

Background: We evaluated the value of pre-treatment positron-emission tomography−computed tomography (PET-CT)-based radiomic features in predicting the locoregional progression-free survival (LR-PFS) of patients with inoperable or unresectable oesophageal cancer. Material and Methods: Forty-six patients were included and 230 radiomic parameters were extracted. After a principal component analysis (PCA), we identified the more robust radiomic parameters, and we used them to develop a heatmap. Finally, we correlated these radiomic features with LR-PFS. Results: The median follow-up time was 17 months. The two-year LR-PFS and PFS rates were 35.9% (95% CI: 18.9−53.3) and 21.6% (95%CI: 10.0−36.2), respectively. After the correlation analysis, we identified 55 radiomic parameters that were included in the heatmap. According to the results of the hierarchical clustering, we identified two groups of patients presenting statistically different median LR-PFSs (22.8 months vs. 9.9 months; HR = 2.64; 95% CI 0.97−7.15; p = 0.0573). We also identified two radiomic features (“F_rlm_rl_entr_per” and “F_rlm_2_5D_rl_entr”) significantly associated with LR-PFS. Patients expressing a “F_rlm_2_5D_rl_entr” of <3.3 had a better median LR- PFS (29.4 months vs. 8.2 months; p = 0.0343). Patients presenting a “F_rlm_rl_entr_per” of <4.7 had a better median LR-PFS (50.4 months vs. 9.9 months; p = 0.0132). Conclusion: We identified two radiomic signatures associated with a lower risk of locoregional relapse after CRT.

The Key Clinical Questions of Neoadjuvant Chemoradiotherapy for Resectable Esophageal Cancer—A Review

Over 50% of individuals with esophageal cancer (EC) present with advanced stages of the disease; therefore, their outcome following surgery alone is poor, with only 25%–36% being alive 5 years post-surgery. Based on the evidence that the CROSS and NEOCRTEC5010 trials provided, neoadjuvant chemoradiotherapy (nCRT) is now the standard therapy for patients with locally advanced EC. However, there are still many concerning clinical questions that remain controversial such as radiation dose, appropriate patient selection, the design of the radiation field, the time interval between chemoradiotherapy (CRT) and surgery, and esophageal retention. With immune checkpoint inhibitors (ICIs) rapidly becoming a mainstay of cancer therapy, along with radiation, chemotherapy, and surgery, the combination mode of immunotherapy is also becoming a hot topic of discussion. Here, we try to provide constructive suggestions to answer the perplexing problems and clinical concerns for the progress of nCRT for EC in the future.

Chemoradiotherapy Followed by Active Surveillance Versus Standard Esophagectomy for Esophageal Cancer: A Systematic Review and Individual Patient Data Meta-analysis

OBJECTIVE

To compare overall survival of patients with a cCR undergoing active surveillance versus standard esophagectomy.

SUMMARY OF BACKGROUND DATA

One-third of patients with esophageal cancer have a pathologically complete response in the resection specimen after neoadjuvant chemoradiotherapy. Active surveillance may be of benefit in patients with cCR, determined with diagnostics during response evaluations after chemoradiotherapy.

METHODS

A systematic review and meta-analysis was performed comparing overall survival between patients with cCR after chemoradiotherapy undergoing active surveillance versus standard esophagectomy. Authors were contacted to supply individual patient data. Overall and progression-free survival were compared using random effects meta-analysis of randomized or propensity score matched data. Locoregional recurrence rate was assessed. The study-protocol was registered (PROSPERO: CRD42020167070).

RESULTS

Seven studies were identified comprising 788 patients, of which after randomization or propensity score matching yielded 196 active surveillance and 257 standard esophagectomy patients. All authors provided individual patient data. The risk of all-cause mortality for active surveillance was 1.08 [95% confidence interval (CI): 0.62-1.87, P = 0.75] after intention-to-treat analysis and 0.93 (95% CI: 0.56-1.54, P = 0.75) after per-protocol analysis. The risk of progression or all-cause mortality for active surveillance was 1.14 (95% CI: 0.83-1.58, P = 0.36). Five-year locoregional recurrence rate during active surveillance was 40% (95% CI: 26%-59%). 95% of active surveillance patients undergoing postponed esophagectomy for locoregional recurrence had radical resection.

CONCLUSIONS

Overall survival was comparable in patients with cCR after chemoradiotherapy undergoing active surveillance or standard esophagectomy. Diagnostic follow-up is mandatory in active surveillance and postponed esophagectomy should be offered to operable patients in case of locoregional recurrence.

Active Surveillance Versus Immediate Surgery in Clinically Complete Responders After Neoadjuvant Chemoradiotherapy for Esophageal Cancer: A Multicenter Propensity Matched Study

OBJECTIVE

This study compared outcomes of patients with esophageal cancer and clinically complete response (cCR) after neoadjuvant chemoradiotherapy (nCRT) undergoing active surveillance or immediate surgery.

BACKGROUND

Since nearly one-third of patients with esophageal cancer show pathologically complete response after nCRT according to CROSS regimen, the oncological benefit of immediate surgery in cCR is topic of debate.

METHODS

Patients with cCR based on endoscopic biopsies and endoscopic ultrasonography with fine-needle aspiration initially declining or accepting immediate surgery after nCRT were identified between 2011 and 2018. Primary endpoint was overall survival (OS). The secondary endpoints were progression-free survival (PFS), rate and timing of distant dissemination, and postoperative outcomes.

RESULTS

Some 98 patients with cCR were identified: 31 in the active surveillance- and 67 in the immediate surgery group with median followup of survivors of 27.7 and 34.8 months, respectively. Propensity score matching resulted in 2 comparable groups (n = 29 in both groups). Patients undergoing active surveillance or immediate surgery had a 3-year OS of 77% and 55% (HR 0.41; 95% CI 0.14-1.20, P = 0.104), respectively. The 3-year PFS was 60% and 54% (HR 1.08; 95% CI 0.44-2.67, P = 0.871), respectively. Patients undergoing active surveillance or immediate surgery had a comparable distant dissemination rate (both groups 28%), radical resection rate (both groups 100%), and severity of postoperative complications (Clav- ien-Dindo grade ≥ 3: 43% vs 45%, respectively).

CONCLUSION

In this retrospective study, OS and PFS in patients with cCR undergoing active surveillance or immediate surgery were not significantly different. Active surveillance with postponed surgery for recurrent disease was not associated with a higher distant dissemination rate or more severe adverse postoperative outcomes.

Omitting surgery in esophageal cancer patients with complete response after neoadjuvant chemoradiotherapy: a systematic review and meta-analysis

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is a standard treatment modality for locally-advanced esophageal cancer. However, patients who achieve clinical complete response (cCR) after nCRT have been reported to have better prognosis. Further, the role of surgery in these patients is controversial. Thus, this meta-analysis aimed to evaluate whether surgery is still useful in patients with cCR after nCRT.

METHODS

We systematically reviewed the MEDLINE, PubMed, Embase, Cochrane library, and Scopus databases for studies on surgical efficacy in complete responders after concurrent chemoradiotherapy for esophageal cancer. The publication date was set to January 1, 2010-January 31, 2020. The hazard ratio (HR) and risk ratio were used to compare the 2-year overall survival (OS), disease-free survival (DFS), incidence of locoregional failure, distant metastasis, and treatment mortality between the nCRT and nCRT plus surgery groups.

RESULTS

Six articles involving 609 patients were included. There was a significant benefit of nCRT for OS (HR = 0.80, 95% confidence interval [CI] 0.64-0.99, p = 0.04), but not for DFS (HR = 1.55, 95% CI 0.35-6.86, p = 0.56). The nCRT group tended to have lower mortality than the nCRT plus surgery group (risk ratio = 0.15, 95% CI 0.02-1.18, p = 0.07).

CONCLUSION

Omitting surgery provides better OS in complete responders after nCRT. Adding surgery could increase the morbidity and mortality and decrease the quality of life. Thus, nCRT alone could be a feasible approach for patients with cCR.

Prognostic and predictive values of interim 18F-FDG PET during neoadjuvant chemoradiotherapy for esophageal cancer: a systematic review and meta-analysis

PURPOSE

To determine the prognostic and predictive value of early metabolic response assessed by a change in standardized uptake value (SUV) on interim 18F-FDG PET in patients with esophageal cancer undergoing neoadjuvant chemoradiotherapy.

METHODS

PubMed and Embase were searched up until 10 September, 2020, for studies evaluating a change in SUV on interim 18F-FDG PET for predicting a pathologic response, progression-free survival (PFS), or overall survival (OS) in patients with esophageal cancer. The sensitivity and specificity for predicting a pathologic response were pooled using bivariate and hierarchical summary receiver operating characteristic (HSROC) models. Meta-analytic pooled hazard ratios (HRs) and their 95% confidence intervals (CIs) were derived using a random-effects model.

RESULTS

A total of 11 studies (695 patients) were included in the meta-analysis. For nine studies assessing predictive accuracy, the pooled sensitivity and specificity of an early metabolic response for predicting a pathologic response were 0.80 (95% CI 0.61-0.91) and 0.54 (95% CI 0.45-0.63), respectively. The area under the HSROC curve was 0.64 (95% CI 0.60-0.68). Across the nine studies assessing prognostic value, an early metabolic response determined by interim PET showed pooled HRs for predicting PFS and OS of 0.44 (95% CI, 0.30-0.63) and 0.42 (95% CI, 0.31-0.56), respectively.

CONCLUSION

Change in SUV on interim 18F-FDG PET had significant prognostic value and moderate predictive value for a pathologic response in esophageal cancer treated with neoadjuvant chemoradiotherapy. Interim 18F-FDG PET may help prognostic stratification and guide treatment planning in oncologic practice.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Induction chemoradiotherapy including docetaxel, cisplatin, and 5-fluorouracil for locally advanced esophageal cancer

BACKGROUND

Locally advanced esophageal cancer (EC) invading surrounding organs (T4b) is difficult to treat. In general, definitive chemoradiotherapy (d-CRT) has been chosen as treatment for such cases. However, the outcome has not been good. Recently, the effectiveness of d-CRT with docetaxel, cisplatin, and 5-fluorouracil (DCF-RT) has been reported. Furthermore, surgery after d-CRT has a better prognosis than d-CRT alone in some reports, although it has a high risk of surgical complications. This study investigated the effectiveness and safety of induction DCF-RT.

METHODS

The subjects were EC patients who underwent induction DCF-RT in Okayama University Hospital between January 2011 and December 2017. Their background characteristics, treatment details, histopathological factors, adverse events during CRT, postoperative complications, and overall survival (OS) were assessed.

RESULTS

A total of 16 cases were performed induction DCF-RT. In 10 cases, death occurred, with 9 cancer-related deaths, and 1 death due to other disease. For all cases, OS was 37.5% at 3 years. 12 cases underwent esophagectomy after DCF-RT. Their OS was 50% at 3 years. 13 patients (81.3%) had Grade 3 febrile neutropenia. In 7 cases (62.5%), fasting for the treatment of diarrhea was needed. Three patients (25%) developed anastomotic leakage. Some recurrent laryngeal nerve paralysis was observed in 6 cases (50%).

CONCLUSION

Although the rates of adverse events and surgical complications were slightly higher than in past reports, they were acceptable. It is useful to perform induction DCF-RT for T4b EC.

Post-chemoradiotherapy FDG PET with qualitative interpretation criteria for outcome stratification in esophageal squamous cell carcinoma

Objectives

Post-chemoradiotherapy (CRT) FDG PET is a useful prognosticator of esophageal cancer. However, debate on the diverse criteria of previous publications preclude worldwide multicenter comparisons, and even a universal practice guide. We aimed to validate a simple qualitative interpretation criterion of post-CRT FDG PET for outcome stratification and compare it with other criteria.

Methods

The post-CRT FDG PET of 114 patients with esophageal squamous cell carcinoma (ESCC) were independently interpreted using a qualitative 4-point scale (Qual_4PS) that identified focal esophageal FDG uptake greater than liver uptake as residual tumor. Cohen’s κ coefficient (κ) was used to measure interobserver agreement of Qual_4PS. The Kaplan-Meier method and Cox proportional hazards regression analyses were used for survival analysis. Other criteria included a different qualitative approach (Qual_BK), maximal standardized uptake values (SUV_max3.4, SUV_max2.5), relative change of SUV_max between pre- and post-CRT FDG PET (ΔSUV_max), mean standardized uptake values (SUV_mean), metabolic volume (MV) and total lesion glycolysis (TLG).

Results

Overall interobserver agreement on the Qual_4PS criterion was excellent (κ: 0.95). Except the Qual_BK, SUV_max2.5, and TLG, all the other criteria were significant predictors for overall survival (OS). Multivariable analysis showed only Qual_4PS (HR: 15.41; P = 0.005) and AJCC stage (HR: 2.47; P = 0.007) were significant independent variables. The 2-year OS rates of Qual_4PS(‒) patients undergoing CRT alone (68.4%) and patients undergoing trimodality therapy (62.5%) were not significant different, but the 2-year OS rates of Qual_4PS(+) patients undergoing CRT alone (10.0%) were significantly lower than in patients undergoing trimodality therapy (42.1%).

Conclusions

The Qual_4PS criterion is reproducible for assessing the response of ESCC to CRT, and valuable for predicting survival. It may add value to response-adapted treatment for ESCC patients, and help to decide whether surgery is warranted after CRT.

Clinical complete response after chemoradiotherapy for carcinoma of thoracic esophagus: Is esophagectomy always necessary? A systematic review and meta-analysis

Background

Although a clinical complete response (cCR) after chemoradiotherapy (CRT) could lead to a better prognosis, the choice of a following strategy, such as surgical or non‐surgical approach, remains controversial.

Methods

All articles relevant to a comparison of surgical and non‐surgical treatment (including further definitive chemoradiotherapy or active surveillance) for esophageal carcinoma patients with a cCR after CRT were retrieved for meta‐analysis. The final date for data retrieval was 30 June 2018.

Results

Four retrospective studies including 648 patients met the inclusion criteria: 620 with squamous cell carcinoma and 28 with adenocarcinoma. The CRT + surgery group had an advantage over the non‐surgery group in regard to two‐year disease‐free survival (DFS); however, the two groups showed similar results in five‐year DFS. The CRT + surgery group had an advantage over the non‐surgery group in two‐year overall survival (OS); nevertheless, the two groups showed similar results in five‐year OS.

Conclusions

Based on the available evidence, the addition of surgery to thoracic locally advanced esophageal carcinoma patients with a cCR after neoadjuvant CRT provided no advantage to long‐term survival. As an exception, the two‐year DFS and OS could be improved. This research conclusion might be more suitable to patients with squamous cell carcinoma.

Prognostic value of metabolic response measured by 18F-FDG-PET in oesophageal cancer patients treated with definitive chemoradiotherapy

BACKGROUND

This study aimed to assess the efficacy of fluorine-18 fluorodeoxyglucose (F-FDG)-PET for predicting overall survival (OS) and disease-free survival (DFS) in oesophageal cancer patients after definitive chemoradiotherapy (CRT) and prognostic importance of metabolic response detected by post-treatment PET at least 3 months after completing CRT.

MATERIALS AND METHODS

Data from 58 oesophageal cancer patients receiving definitive CRT were retrospectively analysed. Post-treatment F-FDG-PET was delivered at a median of 3.2 (range, 3.0-6.4) months after CRT. The impact of metabolic response determined by post-treatment F-FDG-PET, maximum post-treatment standardized uptake value (SUVmax) and percent SUV change (pretreatment to post-treatment) on survival was analysed.

RESULTS

The median follow-up was 19.7 (range, 4.2-91.9) months for all patients and 28.2 (range, 13.7-91.9) months for survivors. The mean pretreatment and post-treatment SUVmax and the median percent SUV decrease were 18.6±6.4, 6.2±4.6 and -73% (+13 to -100%). Pretreatment SUVmax was higher in patients with locoregional or distant failure than in those without (P<0.001). Pretreatment SUVmax was lower in patients with a complete response (CR) than in those without a CR (P=0.006). Two-year OS and DFS were higher in patients with CR compared with those without CR (P<0.001). CR rates detected by post-treatment F-FDG-PET were lower in patients with lymph node metastases or longer tumours than in those with shorter tumours or no metastases. During multivariate analysis, post-treatment SUVmax was a significant predictor for OS, and post-treatment SUVmax, percent SUV decrease and tumour length were significant prognostic factors for DFS.

CONCLUSION

Metabolic response assessed by post-treatment F-FDG-PET at least 3 months after CRT showed that post-treatment SUVmax and percent SUV change were important survival predictors.

Factors associated with false-negative endoscopic biopsy results after neoadjuvant chemoradiotherapy in patients with esophageal squamous cell carcinoma

The usefulness of endoscopic biopsy following neoadjuvant chemoradiotherapy (nCRT) is limited because of its high false-negative (FN) rates. However, data on the factors associated with FN biopsy results remain scarce. The purpose of this study was to investigate factors associated with FN results on endoscopic biopsies in patients with esophageal squamous cell carcinoma (ESCC) following nCRT. We retrospectively reviewed the records of ESCC patients who were treated at the Chang Gung Memorial Hospital, Taoyuan, Taiwan, between 1999 and 2013. Inclusion criteria were receiving nCRT as first-line treatment before esophagectomy and having been preoperatively submitted to an endoscopic biopsy. Endoscopic findings at the lesion site were classified into 6 distinct categories: stricture, tumor, ulcer, scar, other findings, or normal. Univariate and multivariate analyses were used to identify factors associated with FN biopsy findings. A total of 227 patients were selected, of which 92 (41.9%) had positive biopsy results. Among patients with negative biopsy findings (n = 135), 85 were found to have residual cancer on the resected esophagus. Multivariate analysis identified endoscopic findings as the only independent predictor of FN biopsy results. The negative predictive values were 77.8%, 61.9%, 52.6%, 30.3%, 23.1%, and 20.0% for the normal, scar, other findings, ulcer, stricture, and tumor categories, respectively (P < 0.001). In ESCC patients, the FN rate of endoscopic biopsy after nCRT is associated with the type of residual lesion.