Cetuximab in combination with chemoradiotherapy in Chinese patients with non-resectable, locally advanced esophageal squamous cell carcinoma: a prospective, multicenter phase II trail

A Meta-Analysis and Review of Radiation Dose Escalation in Definitive Radiation Therapy between Squamous Cell Carcinoma and Adenocarcinoma of Esophageal Cancer

Esophageal cancer, ranked as the eighth most prevalent cancer globally, is characterized by a low survival rate and poor prognosis. Concurrent chemoradiation therapy (CCRT) is the standard therapy in the non-surgical treatment of localized carcinoma of the esophagus. Nevertheless, the radiation doses employed in CCRT remain notably lower compared to the curative definite chemoradiation therapy utilized in the management of other carcinomas. In order to increase the local control rates and enhance the treatment outcomes, several clinical trials have used high-dose radiation to analyze the effect of dose escalation. Despite the integration of technically advanced RT schemes such as intensity-modulated radiation therapy (IMRT), the results of these trials have failed to demonstrate a significant improvement in overall survival or local progression-free survival. In this review, we investigated previous clinical trials to determine the ineffectiveness of radiation dose escalation in the context of CCRT for esophageal cancer. We aim to clarify the factors contributing to the limited efficacy of escalated radiation doses in improving patient outcomes. Furthermore, we delve into recent research endeavors, exploring prospective radiation dose modifications being altered based on the histological characteristics of the carcinoma. The exploration of these recent studies not only sheds light on potential refinements to the existing treatment protocols but also seeks to identify novel approaches that may pave the way for more efficacious and personalized therapeutic strategies for esophageal cancer management.

Toward Targeted Therapies in Oesophageal Cancers: An Overview

Oesophageal cancer is one of the leading causes of cancer-related death worldwide. Oesophageal cancer occurs as squamous cell carcinoma (ESCC) or adenocarcinoma (EAC). Prognosis for patients with either ESCC or EAC is poor, with less than 20% of patients surviving more than 5 years after diagnosis. A major progress has been made in the development of biomarker-driven targeted therapies against breast and lung cancers, as well as melanoma. However, precision oncology for patients with oesophageal cancer is still virtually non-existent. In this review, we outline the recent advances in oesophageal cancer profiling and clinical trials based on targeted therapies in this disease.

Safety and efficacy of anti-EGFR monoclonal antibody (SCT200) as second-line therapy in advanced esophageal squamous cell carcinoma

OBJECTIVE

The mainstay treatment of esophageal squamous cell carcinoma (ESCC) involves chemotherapy and immunotherapy. However, alternative therapies are required for patients who are refractory or intolerant to existing therapies.

METHODS

In this single-arm, multicenter, open-label phase Ib study, 30 patients received an intravenous infusion of SCT200, an antiepidermal growth factor receptor (EGFR) monoclonal antibody, 6.0 mg/kg once a week for 6 weeks, followed by 8.0 mg/kg once every 2 weeks until disease progression or intolerable toxicity. The primary endpoint was the objective response rate (ORR). The secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Thirty patients were enrolled between July 2018 and May 2019. The ORR was 16.7% (95% CI: 5.6%-34.7%). The median PFS and OS were 3.1 months (95% CI: 1.5-4.3) and 6.8 months (95% CI: 4.7-10.1), respectively. A numerical difference without any statistical significance in ORR was observed in patients with different EGFR expressions (≥ 50%: 25.0% vs. < 50%: 0%, P = 0.140) or TP53 mutation abundance (< 10%: 23.8% vs. ≥ 10%: 0%, P = 0.286). Improved median PFS (3.4 vs. 1.4 months, P = 0.006) and OS (8.0 vs. 4.2 months, P = 0.027) were associated with TP53 mutation abundance of < 10%. The most common treatment-related adverse events of grade 3 or 4 (occurring in ≥ 2 patients) were hypomagnesemia [7 (23.3%)] and rash [2 (6.7%)]. No treatment-related death occurred.

CONCLUSIONS

SCT200 monotherapy as the second- or further-line treatment for advanced ESCC showed favorable efficacy, with an acceptable safety profile. TP53 mutation abundance might serve as a potential predictive biomarker.

Advances in the pharmacotherapeutic management of esophageal squamous cell carcinoma

INTRODUCTION

Esophageal squamous cancer remains an important cause of mortality worldwide with two new immunotherapy drugs recently approved for metastatic disease.

AREAS COVERED

The authors review the epidemiology and genomics of esophageal squamous cell carcinoma. They also examine prior trials involving targeted agents under investigation as well immunotherapies that have been approved and novel combinations.

EXPERT OPINION

Great advances have been made in characterizing the molecular changes in esophageal carcinoma. However, relatively few drugs have shown benefit in this disease. Targeted therapies have not shown to improve survival although many of these trials did not explore potential biomarkers. Pembrolizumab and nivolumab are now approved for esophageal squamous carcinoma but much more data are needed to understand how these agents may be used in non-metastatic settings. Novel treatments are still required as overall prognosis remains poor.

A review of radiation-induced lymphopenia in patients with esophageal cancer: an immunological perspective for radiotherapy

Radiotherapy is a frequently utilized therapeutic modality in the treatment of esophageal cancer (EC). Even though extensive studies are carried out in radiotherapy for EC, the design of the clinical target volume and the radiation dose is not satisfactorily uniform. Radiotherapy acts as a double-edged sword on the immune system; it has both an immunostimulatory effect and an immunosuppressive effect. Radiation-induced lymphopenia and its potential association with tumor control and survival outcomes remain to be understood. The advent of immunotherapy has renewed the focus on preserving a pool of functioning lymphocytes in the circulation. In this review, we summarize the potential impact mechanisms of radiotherapy on peripheral blood lymphocytes and the prognostic role of radiation-induced lymphopenia in patients with EC. We also propose the concept of organs-at-risk of lymphopenia and discuss potential strategies to mitigate its effects on patients with EC. From an immunological perspective, we put forward the hypothesis that optimizing radiation modalities, radiation target volume schemes, and radiation doses could help to reduce radiation-induced lymphopenia risks and maximize the immunomodulatory role of radiotherapy. An optimized radiotherapy plan may further enhance the feasibility and effectiveness of combining immunotherapy with radiotherapy for EC.

Phase II Trial of Epigallocatechin-3-Gallate in Acute Radiation-Induced Esophagitis for Esophagus Cancer

Acute radiation-induced esophagitis (ARIE) is among the most serious form of toxicities associated with definitive radiotherapy or chemoradiotherapy used for treatment of patients with esophageal cancer. Our preliminary phase I and II trials of lung cancer patients who received radiotherapy indicated epigallocatechin-3-gallate (EGCG) as a promising therapeutic option against ARIE. Therefore, we conducted a prospective phase II study to validate the efficacy and safety of EGCG in the treatment of ARIE. The patients who received chemoradiotherapy or definitive radiotherapy for treatment of esophageal cancer in the Shandong Cancer Hospital and Institute in China were enrolled for the present study. EGCG (440 μM) was administered with first onset of ARIE and then at weeks after final radiotherapy. The patients were monitored every week for dysphagia, Radiation Therapy Oncology Group (RTOG) score, and esophagitis-related pain. Moreover, tumor response and the effect on survival following the treatment were also evaluated. Comparison of the RTOG score in the first, second, third, fourth, fifth, and even sixth week after EGCG prescription and the first and second week after radiotherapy with baseline indicates a significant reduction. The tumor response rate was 86.3%. The overall survival rate in 1, 2, and 3 years was found to be 74.5%, 58%, and 40.5%. Oral administration of EGCG solution seems to be feasible for treating ARIE in patients with esophageal cancer who receive radiation therapy. EGCG might be an ARIE-reliever without compromising the efficacy of radiation therapy. A randomized study with a control group is needed for further evaluation.

What Is the Optimal Radiotherapy Target Size for Non-Operable Esophageal Cancer? A Meta-Analysis

Definitive radiotherapy has an affirmative role in treating non-operable esophageal cancer; however, the controversy between elective lymph node irradiation (ENI) and involved-field irradiation (IFI) still remains. To ascertain the benefits and disadvantages of the two radiation target volumes, we performed a meta-analysis with 7 related publications. According to our findings, patients treated with ENI and IFI had nearly identical 1, 2, and 3-year survival rates (pooled odds ratio [OR] = 1.004, p = 0.980, and pooled OR = 1.15, p = 0.594, and pooled OR = 0.918, p = 0.679, respectively). Likewise, no significant differences were detected in local recurrence rates (pooled OR = 1.04, p = 0.883), regional recurrence rates (pooled OR = 0.65, p = 0.555), and distant metastasis rates (pooled OR = 1.29, p = 0.309) between the two treatment groups. However, IFI could significantly decrease the incidences of acute radiation esophagitis (pooled OR = 2.30, p = 0.001) and late pneumonia (pooled OR = 2.52, p = 0.04) compared with ENI. This meta-analysis provides evidence that IFI is more feasible for non-operable esophageal cancer than ENI.

Slight advantages of nimotuzumab versus cetuximab plus concurrent chemoradiotherapy in locally advanced esophageal squamous cell carcinoma

This study aimed to compare the efficacy of nimotuzumab (Nimo) versus cetuximab (C225) plus concurrent chemoradiotherapy (CCRT) in locally advanced esophageal squamous cell carcinoma (LA-ESCC). A total of 95 patients with LA-ESCC were retrospectively reviewed, including 65 in Nimo and 30 in C225. The results showed that the ORR in Nimo (61.0%; CR 22.0%, 13/59; PR 39.0% 23/59) was slightly higher than that in C225 (43.5%; CR 8.7%, 2/23; PR 34.8%, 8/23) but without significant difference (p = 0.81). The DCR was 79.7% vs. 73.9% in C225, favoring Nimo plus CCRT (p = 0.04). The median PFS in Nimo was significantly longer than that in C225 (19.6 months vs. 13.0 months, p = 0.02). The median OS of the whole cohort, the Nimo group and the C225 group were 21.3, 24.5, and 20.9 months, respectively. The rates of OS at 1-, 3-year in Nimo were 77.7% and 33.5%, compared to 73.3% and 20.0% in C225 (HR = 1.17, p = 0.23). Grade 3 or worse hematological toxicity and non-hematological toxicity (radiation esophagitis) in Nimo were similar with that in C225 (21.5% vs. 26.7%, p = 0.91; 26.1% vs. 26.7%, p = 0.56). No grade ≥3 radiation pneumonitis occurred neither Nimo group nor C225 group. Nimo plus CCRT improved DCR and PFS of patients with LA-ESCC and had a tendency of prolonged survival compared to C225 plus CCRT. Our results suggest that the combination of Nimo and CCRT may be a reasonable option in this population.

Enhancement of radiotherapeutic efficacy for esophageal cancer by paclitaxel-loaded red blood cell membrane nanoparticles modified by the recombinant protein anti-EGFR-iRGD

Paclitaxel is widely used as a radiosensitizer for various tumors, including esophageal cancer, but its therapeutic effect remains to be improved. In this study, we constructed a novel nano-radiosensitizer, anti-EGFR-iRGD-conjugated (iE)-PRNPs, by conjugating the recombinant protein anti-epidermal growth factor receptor (EGFR)-internalizing arginine-glycine-aspartic (iRGD) to the surface of paclitaxel-loaded red blood cell membrane nanoparticles (PRNPs). The iE-PRNPs were confirmed to possess tumor-targeting, high penetrability, and sustained release properties that free paclitaxel does not possess. Compared with that of paclitaxel, the sensitizer enhancement ratio of iE-PRNPs was significantly increased (1.32-fold and 1.25-fold) in esophageal cancer cells with high and low expression levels of EGFR, respectively. Additionally, compared with that of unmodified PRNPs, the sensitizer enhancement ratio of iE-PRNPs in EGFR-overexpressing esophageal cancer cells was significantly increased (1.27-fold), while that of PRNPs in esophageal cancer cells with a low EGFR expression level increased slightly (1.06-fold). The improved radiosensitization effect was associated with enhanced G2/M arrest, increased reactive oxygen species, and more effective induction of DNA double-strand breaks. In summary, iE-PRNPs appear to be a novel type of radiosensitizer with the potential to overcome the bottleneck of esophageal cancer radiotherapeutic efficacy.

18F-deoxyglucose positron emission tomography/computed tomography to predict local failure in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) patients are at risk for local failure (LF) following treatment. Predicting tumor regions at high risk for local failure before radiotherapy may increase treatment efficacy by permitting an escalated radiation dose specifically to those regions critical for tumor control. Forty-one patients with non-resectable locally advanced ESCC underwent ¹⁸F-deoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging before concurrent chemoradiotherapy (CCRT). After CCRT, a second (failure) FDG PET/CT was performed in cases of relapse. Failure FDG PET/CT scans were fused to pre-treatment scans to identify tumor regions at high risk for LF. Within a median follow-up time of 26 months, 20 patients (48.8%) had LF. In 19 patients, the failure occurred within a pre-treatment high FDG uptake region; the failure occurred outside these regions in only one patient. Pre-treatment metabolic tumor volume (MTV) was independently associated with LF (P<0.001, HR 1.128, 95% CI: 1.061–1.198). LF was more likely in patients with MTVs ≥27 cm³. In initial PET/CT images, when 50% maximum standardized uptake value (SUV_max) was used as the threshold, delineated subvolumes overlapped LF regions. These results confirm that LF occurs most commonly within pre-treatment high FDG uptake regions.

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.

Treatment of esophageal cancer with radiation therapy -a pan-Chinese survey of radiation oncologists

Lots of controversies were found about the treatment in relation to radiation therapy (RT) for esophageal squamous cell carcinoma (ESCC). We designed a questionnaire of these controversies to do a pan-Chinese survey of radiation oncologists (ROs). For operable ESCC, 53% ROs chose surgery plus postoperative chemoradiotherapy (CRT), while 40% chose preoperative CRT plus surgery. For target volume of postoperative RT, most ROs (92%) would delineate tumor bed plus involved lymph nodes region before surgery. For definitive RT, most ROs (81%) would give patients higher RT dose to 60-65Gy. For radiation target volume, most ROs would give patients prophylactic irradiation of the bilateral superclavicular-lymph nodes region for cervical ESCC (93%), and the left gastric lymph nodes region for lower thoracic ESCC (72%). For the treatment of mediastinal lymph nodes, 72% ROs preferred elective nodal irradiation, while 28% did the involved nodal irradiation. For concurrent chemotherapy regimen, PF (5-Fu + cisplatin) and TP (cisplatin + paclitaxel) were used widely (49% and 46%, respectively). During simulation, four-dimensional computer tomography (4D CT) was not widely used (48%), even for cervical or lower thoracic ESCC (52%). For daily RT delivery, only 66% ROs would perform imaging guidance RT daily. In summary, more controversies existed in the treatment of ESCC with RT in China, including treatment strategy, radiation dose and target contour. Future goals include standardization of treatment strategy, radiation dose, and target contour, and application of 4D CT and daily imaging guidance, and pursuit of randomized trials in Chinese population.

Overview of different available chemotherapy regimens combined with radiotherapy for the neoadjuvant and definitive treatment of esophageal cancer

INTRODUCTION

Neoadjuvant chemoradiotherapy (CTRT) is the current standard of care for treatment of locally advanced cancer of the esophagus or gastroesophageal junction. Many efforts have been made over the last years to identify the best chemotherapy and radiotherapy combination regimen, but specific randomized trials addressing this issue are still lacking. Areas covered: A systematic review of the literature was performed searching in PubMed all published studies of combinations CTRT regimens for operable or unresectable esophageal cancer to describe activity and toxicity. Studies considered were prospective series or clinical phase II-III trials including at least 40 patients and published in English language. Expert commentary: Long-term results of CROSS trial have established RT combined with carboplatin plus paclitaxel chemotherapy as the preferred neoadjuvant treatment option for both squamous and adenocarcinoma of the esophagus. More effective multimodal treatment strategies integrating novel biological agents including immunotherapy and based on an extensive molecular tumor characterization are eagerly awaited.

Long-term results and recurrence patterns from SCOPE-1: a phase II/III randomised trial of definitive chemoradiotherapy +/- cetuximab in oesophageal cancer

BACKGROUND

The SCOPE-1 study tested the role of adding cetuximab to conventional definitive chemoradiotherapy (dCRT), and demonstrated greater toxicity and worse survival outcomes. We present the long-term outcomes and patterns of recurrence.

METHODS

SCOPE-1 was a phase II/III trial in which patients were randomised to cisplatin 60 mg m-2 (day 1) and capecitabine 625 mg m-2 bd (days 1-21) for four cycles +/- cetuximab 400 mg m-2 day 1 then by 250 mg m-2 weekly. Radiotherapy consisted of 50 Gy/25# given concurrently with cycles 3 and 4. Recruitment was between February 2008 and February 2012, when the IDMC recommended closure on the basis of futility.

RESULTS

About 258 patients (dCRT=129; dCRT+cetuximab (dCRT+C)=129) were recruited from 36 centres. About 72.9% (n=188) had squamous cell histology. The median follow-up (IQR) was 46.2 (35.9-48.3) months for surviving patients. The median overall survival (OS; months; 95% CI) was 34.5 (24.7-42.3) in dCRT and 24.7 (18.6-31.3) in dCRT+C (hazard ratio (HR)=1.25, 95% CIs: 0.93-1.69, P=0.137). Median progression-free survival (PFS; months; 95% CI) was 24.1 (15.3-29.9) and 15.9 (10.7-20.8) months, respectively (HR=1.28, 95% CIs: 0.94-1.75; P=0.114). On multivariable analysis only earlier stage, full-dose RT, and higher cisplatin dose intensity were associated with improved OS.

CONCLUSIONS

The mature analysis demonstrates that the dCRT regimen used in the study provided useful survival outcomes despite its use in patients who were largely unfit for surgery or who had inoperable disease. Given the competing risk of systemic and local failure, future studies should continue to focus on enhancing local control as well as optimising systemic therapy.

The lymphocyte-monocyte ratio predicts tumor response and survival in patients with locally advanced esophageal cancer who received definitive chemoradiotherapy

Background

The lymphocyte–monocyte ratio (LMR), a simple biomarker that can reflect the antitumor immune response of the host, has been associated with patient prognosis in several solid tumors. The aim of this study was to evaluate whether LMR can predict clinical tumor response and prognosis in patients with locally advanced esophageal squamous cell carcinoma (ESCC) who received definitive chemoradiotherapy (CRT).

Patients and methods

A total of 162 advanced ESCC patients treated at our institution between January 2012 and December 2013 were retrospectively recruited for analysis. Patients were treated with a platinum-based bimodal cytotoxic drug chemotherapy and concurrent radiation therapy. The LMR was calculated from blood counts in samples collected prior to treatment initiation. The predictive value of LMR for clinical tumor response and prognosis was examined.

Results

The LMR before CRT was significantly higher in 48 patients who achieved clinical complete response (CR) compared to that in patients who did not achieve clinical CR (4.89±1.17 vs 3.87±1.29, P<0.001). Compared to their matched counterparts, patients in the high LMR group (LMR >4.02) showed a good clinical tumor response (P<0.05). A significant independent association between a high pretreatment LMR and better outcomes was identified in a multivariate analysis for progression-free survival (PFS; hazard ratio [HR]=2.17; P<0.001) and overall survival (OS; HR=2.02; P=0.002).

Conclusion

In ESCC patients, a high LMR before treatment, which indicates a robust host immune system, is associated with both a good clinical tumor response after definitive CRT and favorable prognosis.

Targeted therapy in esophageal cancer

An increasing number of patients are diagnosed with esophageal cancer at an advanced stages, and only a small group of them can benefit from the traditional chemotherapy and radiotherapy. So far, multiple monoclonal antibodies and tyrosine kinase inhibitors have been developed, alone or in combination with traditional therapy, to improve the prognosis of patients with advanced esophageal cancer. This review summarizes the recent advances of targeted therapies against EGFR, HER2, VEGFR and c-MET in esophageal cancer. More clinical trials should be performed to evaluate the efficacy and safety of various targeted therapy regimens. Future basic research should focus on investigating the molecular mechanisms of therapeutic targets in esophageal cancer.

Successes and Failures of Combined Modalities in Upper Gastrointestinal Malignancies: New Directions

Upper gastrointestinal malignancies generally have moderate to poor cure rates, even in the earliest stages, thereby implying that both local and systemic treatments have room for improvement. Therapeutic options are broadening, however, with the development of new immunotherapies and targeted agents, which can have synergistic effects with radiotherapy. Here we discuss the current state of combined modality therapy for upper gastrointestinal malignancies, specifically recent successes and setbacks in trials of radiation therapy with targeted therapies, vaccines, immunotherapies, and chemotherapies.

Postoperative radiation in esophageal squamous cell carcinoma and target volume delineation

Esophageal cancer is the sixth leading cause of cancer death worldwide, and patients who are treated with surgery alone, without neoadjuvant therapies, experience frequent relapses. Whether postoperative therapies could reduce the recurrence or improve overall survival is still controversial for these patients. The purpose of our review is to figure out the value of postoperative adjuvant therapy and address the disputes about target volume delineation according to published data. Based on the evidence of increased morbidity and disadvantages on patient survival caused by postoperative chemotherapy or radiotherapy (RT) alone provided by studies in the early 1990s, the use of postoperative adjuvant therapies in cases of esophageal squamous cell carcinoma has diminished substantially and has been replaced gradually by neoadjuvant chemoradiation. With advances in surgery and RT, accumulating evidence has recently rekindled interest in the delivery of postoperative RT or chemoradiotherapy in patients with stage T3/T4 or N1 (lymph node positive) carcinomas after radical surgery. However, due to complications with the standard radiation field, a nonconforming modified field has been adopted in most studies. Therefore, we analyze different field applications and provide suggestions on the optimization of the radiation field based on the major sites of relapse and the surgical non-clearance area. For upper and middle thoracic esophageal carcinomas, the bilateral supraclavicular and superior mediastinal areas remain common sites of recurrence and should be encompassed within the clinical target volume. In contrast, a consensus has yet to be reached regarding lower thoracic esophageal carcinomas; the “standard” clinical target volume is still recommended. Further studies of larger sample sizes should focus on different recurrence patterns, categorized by tumor locations, refined classifications, and differing molecular biology, to provide more information on the delineation of target volumes.

Involved-field radiotherapy for esophageal squamous cell carcinoma: theory and practice

Esophageal carcinoma (EC) is characterized by a high rate of lymph node metastasis and its spread pattern is not always predictable. Chemoradiotherapy has an important role in the treatment of EC in both the inoperable and the pre-operative settings. However, regarding the target volume for radiation, different clinical practices exist. Theoretically, in addition to the clinical target volume administered to the gross lesion, it might seem logical to deliver a certain dose to the uninvolved regional lymph node area at risk for microscopic disease. However, in practice, it is difficult because of the intolerance of normal tissue to radiotherapy (RT), particularly if all regions containing the cervical, mediastinal, and upper abdominal nodes are covered. To date, the use of elective nodal irradiation (ENI) is still controversial in the field of radiotherapy. Some investigators use involved-field radiotherapy (IFRT) in order to reduce treatment-related toxicities. It is thought that micrometastases can be controlled, to some extent, by chemotherapy and the abscopal effects of radiation. It is the presence of overtly involved lymph nodes rather than the micrometastatic nodes negatively affects survival in patients with EC. In another hand, lymph nodes stationed near primary tumors also receive considerable incidental irradiation doses that may contribute to the elimination of subclinical lesions. These data indicate that an irradiation volume covering only the gross tumor is appropriate. When using ENI or IFRT, very few patients experience solitary regional node failure and out-of-field lymph node failure is not common. Primary tumor recurrence and distant metastases, rather than regional lymph node failure, affect the overall survival in patients with EC. The available evidence indicates that the use of ENI seems to prevent or delay regional nodal relapse rather than improve survival. In a word, these data suggest that IFRT is feasible in EC patients.

Tumour delineation in oesophageal cancer - A prospective study of delineation in PET and CT with and without endoscopically placed clip markers

PURPOSE

The objective was to analyse the value of F-18-fluorodesoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) for delineation of the Gross Tumour Volumes (GTVs) in primary radiotherapy of oesophageal cancer.

METHOD

20 consecutive and prospective patients (13 men, 7 women) underwent FDG-PET/CT for initial staging and radiation treatment planning. After endoscopy-guided clipping of the tumour another CT study was acquired. The CT and the FDG-PET/CT were registered with a rigid and a non-rigid registration algorithm to compare the overlap between GTV contours defined with the following methods: manual GTV definition in (1) the CT image of the FDG-PET/CT, (2) the PET image of the FDG-PET/CT, (3) the CT study based on endoscopic clips (CT clip), and (4) in the PET-data using different semi-automatic PET segmentation algorithms including a gradient-based algorithm. The absolute tumour volumes, tumour length in cranio-caudal direction, as well as the overlap with the reference volume (CT-clip) were compared for all lesions and separately for proximal/distal tumours.

RESULTS

In 6 of the patients, FDG-PET/CT discovered previously unknown tumour locations, which resulted in either altered target volumes (n=3) or altered intent of treatment from curative to palliative (n=3) by upstaging to stage IV. For tumour segmentation a large variability between all algorithms was found. For the absolute tumour volumes with CT-clip as reference, no single PET-based segmentation algorithm performed better compared to using the manual CT delineation alone. The best correlation was found between the CT-clip and the gradient based segmentation algorithm (PET-edge, R(2)=0.84) as well as the manual CT-delineation (CT-manual R(2)=0.89). Non-rigid registration between CT and image FDG-PET/CT did not decrease variability between segmentation methods compared to rigid registration statistically significant. For the analysis of tumour length no homogeneous correlation was found.

CONCLUSION

Whereas FDG-PET was highly relevant for staging purposes, CT imaging with clipping of the tumour extension remains the gold standard for GTV delineation.

Involved-field irradiation concurrently combined with nedaplatin/5-fluorouracil for inoperable esophageal cancer on basis of (18)FDG-PET scans: a phase II study

PURPOSE

A prospective study was performed on chemoradiotherapy (CRT) for esophageal cancer using involved-field radiation therapy (IFRT) based on 18-fluorodeoxyglucose positron-emission tomography. The goal of this phase II study was to evaluate the efficacy of the IFRT procedure in newly diagnosed esophageal cancer.

PATIENTS AND METHODS

Eligible patients were adults with newly diagnosed untreated, inoperable esophageal cancer in stages I-IV with lymph node metastases. Patients received nedaplatin 80mg/m(2) per day on day 1, 5-fluorouracil 800mg/m(2) on days 1-4 intravenously repeated every 28days for 2-4 cycles, and combined IFRT. Elective nodal irradiation was not performed. Irradiation was applied only to the primary tumor and positive lymph nodes.

RESULTS

From September 2009 to July 2012, of the 63 patients enrolled, 58 were evaluable for response. The primary end point of isolated out-of-field loco-regional nodal recurrence was seen in only two patients. The expectant rate was assumed to be less than 5%. The threshold value was set as 10% to calculate the number of registrations. Progression-free and overall survival rates at 36months were 47.7% and 51.1%, respectively. The median progression-free survival was 34.6months, and overall survival was 38.4months. Salvage surgery was tried for 11 patients (17.5%) due to residual or recurrent disease.

CONCLUSION

The primary end point of the trial was demonstrated, indicating the efficacy of IFRT in the treatment of inoperable esophageal cancer mostly of squamous cell carcinoma.