Complete metabolic response is not uniformly predictive of complete pathologic response after induction therapy for esophageal cancer

Predicting outcomes in esophageal adenocarcinoma following neoadjuvant chemoradiation: Interactions between tumor response and survival

OBJECTIVES

The prognostic value of tumor regression scores (TRS) in patients with esophageal adenocarcinoma (EAC) who underwent neoadjuvant chemoradiation remains unclear. We sought to investigate the prognostic value of pathologic and metabolic treatment response among EAC patients undergoing neoadjuvant chemoradiation.

METHODS

Patients who underwent esophagectomy for EAC after neoadjuvant CROSS protocol between 2016 and 2020 were evaluated. TRS was grouped according to the modified Ryan score; metabolic response, according to the PERCIST criteria. Variables from endoscopic ultrasound, endoscopic biopsies, and positron emission tomography (primary and regional lymph node standardized uptake values [SUVs]) were collected.

RESULTS

The study population comprised 277 patients. A TRS of 0 (complete response) was identified in 66 patients (23.8%). Seventy-eight patients (28.1%) had TRS 1 (partial response), 97 (35%) had TRS 2 (poor response), and 36 (13%) had TRS 3 (no response). On survival analysis for overall survival (OS), patients with TRS 0 had longer survival compared to those with TRS 1, 2, or 3 (P = .010, P < .001, and P = .005, respectively). On multivariable logistic regression, the presence of signet ring cell features on endoscopic biopsy (odds ratio [OR], 7.54; P = .012) and greater SUV uptake at regional lymph nodes (OR, 1.42; P = .007) were significantly associated with residual tumor at pathology (TRS 1, 2, or 3). On multivariate Cox regression for predictors of OS, higher SUVmax at the most metabolically active nodal station (hazard ratio [HR], 1.08; P = .005) was independently associated with decreased OS, whereas pathologic complete response (HR, 0.61; P = .021) was independently associated with higher OS.

CONCLUSIONS

Patients with pathologic complete response had prolonged OS, whereas no difference in survival was detected among other TRS categories. At initial staging, the presence of signet ring cells and greater SUV uptake at regional lymph nodes predicted residual disease at pathology and shorter OS, suggesting the need for new treatment strategies for these patients.

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

OBJECTIVE

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

SUMMARY OF BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Detecting Pathological Complete Response in Esophageal Cancer after Neoadjuvant Therapy Based on Imaging Techniques: A Diagnostic Systematic Review and Meta-Analysis

INTRODUCTION

Up to 32% of patients with esophageal cancer show a pathological complete response (ypCR) after neoadjuvant therapy. To prevent overtreatment, the indication to perform esophagectomy in these patients should be reconsidered. Implementing an organ-preserving strategy for patients with ypCR requires an accurate assessment of residual disease after neoadjuvant treatment. The aim of this study was to systematically review the effectiveness of imaging techniques used for detection of ypCR after neoadjuvant therapy but before resection in patients with esophageal cancer.

METHODS

A systematic literature search of the Medline, Embase, and Cochrane Library databases was performed from January 1, 2000, to December 13, 2017. Eligible studies were diagnostic studies that compared results of imaging modalities after neoadjuvant therapy to histopathological findings in the resection specimen after esophagectomy. Methodological quality was assessed by the Cochrane Quality Assessment of Diagnostic Accuracy Studies, version 2, model. Primary outcome measures were true positive, false-positive, false-negative, and true negative values of imaging techniques predicting ypCR. A meta-analysis was performed by pooling sensitivities and specificities by using a bivariate model.

RESULTS

A total of 4420 articles were identified. After exclusion of irrelevant titles and abstracts, 360 articles were reviewed in full text. In total, four imaging modalities (computed tomography [CT], positron emission tomography [PET-CT], endoscopic ultrasound [EUS], and magnetic resonance imaging [MRI]) were used for restaging. The meta-analysis was conducted with data from 56 studies involving 3625 patients. The pooled sensitivities of CT, PET-CT, EUS, and MRI for detecting ypCR were 0.35, 0.62, 0.01 and 0.80, respectively, whereas the pooled specificities were 0.83, 0.73, 0.99, and 0.83, respectively. The positive predictive value in detecting ypCR was 0.47 for CT, 0.41 for PET-CT, not applicable for EUS, and 0.61 for MRI.

CONCLUSION

Current imaging modalities such as CT, PET-CT, and EUS seem to be insufficiently accurate to identify complete responders. More accurate diagnostic tests are needed to improve restaging accuracy for patients with esophageal cancer.

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.

Dose-escalated radiotherapy improved survival for esophageal cancer patients with a clinical complete response after standard-dose radiotherapy with concurrent chemotherapy

Purpose

For esophageal cancer patients with a clinical complete response (cCR) after standard-dose radiotherapy with concurrent chemotherapy, data on the survival outcomes and recurrence patterns remain scarce. To evaluate the impact of dose escalation on overall survival for this subset of patients, we carried out the current investigation.

Materials and methods

Medical records of 80 esophageal cancer patients with a cCR after standard-dose radiotherapy with concurrent chemotherapy at our center from 2010 to 2014 were allocated into the standard-dose group (50.4 Gy, observation group) or the radiation dose-escalation group (59.4 Gy, control group). In this cohort study, we compared the outcomes between the 2 groups.

Results

There were no differences in patient characteristics between the 2 groups. The median recurrence-free survival and overall survival times for all patients were 38 and 54 months, respectively. Patients in the control group had significantly better 5-year recurrence-free survival rate (12% vs 0%, p=0.019) and 5-year overall survival rate (42.8% vs 21.0%, p=0.028) than the observation group. Additionally, local control rate was significantly higher in the control group (p=0.04), and ~60% of treatment failures were local failures even for patients achieving cCR after chemoradiotherapy. There were no significant differences in treatment-related toxicities between the groups.

Conclusion

The results of the current study suggest that for esophageal cancer patients with a cCR after standard-dose radiotherapy with concurrent chemotherapy, those with dose-escalated radiotherapy showed significantly better local control, recurrence-free survival, and overall survival than patients receiving 50.4 Gy radiotherapy.

Is pathological complete response after a trimodality therapy, a predictive factor of long-term survival in locally-advanced esophageal cancer? Results of a retrospective monocentric study

OBJECTIVE

To evaluate long-term (5- and 10-year) survival and recurrence rates on the basis of the pathological complete response (pCR) in the specimens of patients with esophageal carcinoma, treated with trimodality therapy.

METHODS

Between 1993 and 2014, all consecutives patients with esophageal locally-advanced non-metastatic squamous cell carcinoma (SCC) or adenocarcinoma (ADC) who received trimodality therapy were reviewed. According to histopathological analysis, patients were divided in two groups with pCR and with pathological residual tumor (pRT). The primary endpoint was overall survival (OS). The secondary endpoints included the disease-free survival (DFS), the recurrence rate, and the predictive factors of overall survival and recurrence.

RESULTS

One hundred and three patients were included: 49 patients with pCR and 54 patients with pRT. The median OS was significantly longer in pCR group than in pRT group (132±22.3 vs. 25.5±4 months), with both 5- and 10-years OS rates of 75.2% vs. 29.1%, and 51.1% vs. 13.6%, respectively (P<0.001). Also, pRT, major postoperative complications (Dindo-Clavien grade>IIIb) and recurrence were the 3 independent predictive factors for worse OS.

CONCLUSIONS

Patients with locally-advanced oesophageal carcinoma, who responded to trimodality therapy with a pCR, could be achieved a 10-year survival rate of 51%.

Radiotherapy for esophageal carcinoma: dose, response and survival

Esophageal cancer (EC) is an extremely aggressive, lethal malignancy that is increasing in incidence worldwide. At present, definitive chemoradiotherapy is accepted as the standard treatment for locally advanced EC. The EC guidelines recommend a radiation dose of 50.4 Gy for definitive treatment, yet the outcomes for patients who have received standard-dose radiotherapy remain unsatisfactory. However, some studies indicate that a higher radiation dose could improve local tumor control, and may also confer survival benefits. Some studies, however, suggest that high-dose radiotherapy does not bring survival benefit. The available data show that most failures occurred in the gross target volume (especially in the primary tumor) after definitive chemoradiation. Based on those studies, we hypothesize that at least for some patients, more intense local therapy may lead to better local control and survival. The aim of this review is to evaluate the radiation dose, fractionation strategies, and predictive factors of response to therapy in functional imaging for definitive chemoradiotherapy in esophageal carcinoma, with an emphasis on seeking the predictive model of response to CRT and trying to individualize the radiation dose for EC patients.

What is the role of neoadjuvant chemotherapy, radiation, and adjuvant treatment in resectable esophageal cancer?

The majority of patients with operable esophageal cancers present with locally advanced disease, for which surgical resection as a sole treatment modality has been historically associated with poor survival. Even following radical resection, most of these patients will eventually succumb to their disease due to distant metastasis. For this reason, there has been intense interest in the role of neoadjuvant therapy. Neoadjuvant therapy primarily consists of either chemotherapy, radiation therapy, or a combination of the two. Multiple studies of variable scope, design, and patient characteristics have been conducted to determine whether neoadjuvant therapy is warranted, and-if so-what is the best modality of treatment. Despite nearly three decades of study, decisions regarding neoadjuvant therapy for esophageal cancer remain controversial. Regardless, the available evidence provided by large, prospective studies supports preoperative chemotherapy as opposed to surgery alone. Therefore, in our opinion, there is no longer any question as to whether induction therapy is appropriate for locally advanced esophageal cancer. Less clear, however, is the evidence that the addition of radiation to chemotherapy in the preoperative setting is superior to neoadjuvant chemotherapy alone. Our group generally advocates for neoadjuvant chemotherapy alone followed by radical esophageal resection. The data for adjuvant therapy are soft, and particularly troubling is the high rate of treatment drop out in trials studying adjuvant therapy. Therefore, we strongly prefer neoadjuvant chemotherapy and reserve adjuvant chemotherapy for those rare, highly selected patients-patients with T1 tumors, for example-who do not receive neoadjuvant treatment and are found to have occult nodal disease at the time of surgery.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Value of CT–PET after neoadjuvant chemoradiation in the prediction of histological tumour regression, nodal status and survival in oesophageal adenocarcinoma

Background

The role of CT–PET after neoadjuvant chemoradiation (nCRT) for prediction of pathological response and oncological outcome in oesophageal and junctional adenocarcinoma (OAC) is unclear. The relationship between complete metabolic response (cMR), pathological complete response (pCR) and nodal status has not been clarified.

Methods

Patients with locally advanced OAC selected to receive nCRT and surgery with curative intent, on the basis of staging that included CT–PET positivity, were included. Repeat scanning (PET2) with an identical protocol was performed 2–4 weeks after completion of nCRT (cisplatin and 5-fluorouracil plus 44 Gy radiation). Changes in [18F]fluorodeoxyglucose uptake, considered as either a maximum standardized uptake value (SUVmax) or a relative reduction (%ΔSUVmax), and PET-predicted nodal status following nCRT were compared with histopathological response, histological node positivity and survival.

Results

One hundred consecutive patients with PET-positive OAC were studied. Following nCRT, PET2 identified M1 disease in 2·0 per cent of patients. There were no significant associations between PET2 SUVmax or %ΔSUVmax with respect to primary tumour stage (ypT) (P = 0.216 and P = 0·975 respectively), tumour regression grade (P = 0·109 and P = 0·232), pCR (P = 0·633 and P = 0·870) or complete resection (R0) (P = 0·440 and P = 0·235). The sensitivity of PET2 for ypN was 10 per cent. %ΔSUVmax was not associated with disease-free or overall survival (P = 0·162 and P = 0·154 respectively). Of 46 patients with a cMR on PET2, 37 (80 per cent) had histological evidence of residual tumour in the resected specimen, and cMR was not associated with overall survival benefit (P = 0·478).

Conclusion

CT–PET following nCRT for OAC has poor prognostic and discriminatory value for clinical application.