Surgery for clinical T3 carcinomas of the upper thoracic oesophagus and the need for new strategies

Caution against simultaneous integrated boost radiotherapy for upper thoracic esophageal squamous cell carcinoma: results from a single-arm phase II trial

PURPOSE

To explore the feasibility and safety of simultaneous integrated boost technology (SIB) with elective nodal irradiation (ENI) to the cervical and upper mediastinal lymph node (LN) regions in upper thoracic esophageal squamous cell carcinoma (ESCC).

MATERIAL AND METHODS

Patients with pathologically proven unresectable upper thoracic ESCC were assigned 50.4 Gy/28 fractions (F) to the clinical target volume (encompassing the ENI area of cervical and upper mediastinal LN regions) and a boost of 63 Gy/28 F to the gross tumor volume. Chemotherapy consisted of courses of concurrent cisplatin (20 mg/m2) and docetaxel (20 mg/m2) weekly for 6 weeks. The primary endpoint was toxicity.

RESULTS

Between Jan 2017 and Dec 2019, 28 patients were included. The median follow-up time for all patients was 24.6 months (range 1.9-53.5). Radiation-related acute toxicity included esophagitis, pneumonia and radiodermatitis, all of which were well managed and reversed. Late morbidity included esophageal ulcer, stenosis, fistula and pulmonary fibrosis. Grade III esophageal stenosis and fistula was seen in 11% (3/28) and 14% (4/28) patients, respectively. The cumulative incidence rate of late esophageal toxicity was 7.7%, 19.2% and 24.6% at 6, 12 and 18 months, respectively. There was significant difference of the occurrence of severe late esophageal toxicity among the different volume levels of the esophagus, and cervical and upper mediastinal LNs which received ≥ 63 Gy stratified by the tertiles (p = 0.014).

CONCLUSIONS

Despite the acceptably tolerated acute toxicity of SIB in concurrent CRT with ENI to the cervical and upper mediastinal LN regions for upper thoracic ESCC, the incidence of severe late esophageal toxicity was relatively high. Cautions are provided against easy clinical application of SIB (50.4 Gy/28F to the CTV, 63 Gy/28F to the GTV) in upper thoracic ESCC. Further exploration on dose optimization is warranted.

Risk Factors for Residual Tumors in Surgery Following Neoadjuvant Chemotherapy for Esophageal Cancer

Neoadjuvant chemotherapy (NAC) followed by esophagectomy is considered the standard treatment for resectable advanced esophageal squamous cell carcinoma in Japan. The purpose of this study was to identify the risk factors for residual tumors in surgery following NAC. We herein described risk factors for residual tumors in surgery following neoadjuvant chemotherapy for thoracic esophageal cancer. We reviewed the medical records of patients in our institution selected by using the following criteria: (1) pathologically confirmed squamous cell carcinoma or adenosquamous carcinoma before treatment; (2) cT1 to cT3; and (3) receipt of thoracotomy performed between 2007 and 2010 with the intention of curative resection after NAC composed of 5-fluorouracil plus cisplatin. The patients were divided into the complete resection group (R0 group), and the macroscopic or microscopic residual tumor group [R(+) group]. A total of 88 patients were eligible (R0, 70 patients; R1, 9 patients; R2, 7 patients; and not resected, 2 patients). There were more cT3 cancers and clinical node-positive diseases in the R(+) group than in the R0 group. Multivariate analysis identified tumor depth (cT3) and tumor location (above the carina) as risk factors for residual tumor. Patients with cT3 esophageal cancer above the carina have a high risk of residual tumor in esophagectomy following NAC. In these patients, more intensive preoperative therapy will be required.

Current advances in esophageal cancer proteomics

We review the current status of proteomics for esophageal cancer (EC) from a clinician's viewpoint. The ultimate goal of cancer proteomics is the improvement of clinical outcome. The proteome as a functional translation of the genome is a straightforward representation of genomic mechanisms that trigger carcinogenesis. Cancer proteomics has identified the mechanisms of carcinogenesis and tumor progression, detected biomarker candidates for early diagnosis, and provided novel therapeutic targets for personalized treatments. Our review focuses on three major topics in EC proteomics: diagnostics, treatment, and molecular mechanisms. We discuss the major histological differences between EC types, i.e., esophageal squamous cell carcinoma and adenocarcinoma, and evaluate the clinical significance of published proteomics studies, including promising diagnostic biomarkers and novel therapeutic targets, which should be further validated prior to launching clinical trials. Multi-disciplinary collaborations between basic scientists, clinicians, and pathologists should be established for inter-institutional validation. In conclusion, EC proteomics has provided significant results, which after thorough validation, should lead to the development of novel clinical tools and improvement of the clinical outcome for esophageal cancer patients. This article is part of a Special Issue entitled: Medical Proteomics.

Influence of preoperative chemotherapy for advanced thoracic oesophageal squamous cell carcinoma on perioperative complications

BACKGROUND

The Japan Clinical Oncology Group (JCOG) 9907 trial has changed the standard of care for advanced thoracic oesophageal cancer in Japan from postoperative chemotherapy to preoperative chemotherapy. The impact of preoperative chemotherapy on the risk of developing postoperative complications remains controversial. This article reports the safety analysis of JCOG9907, focusing on risk factors for postoperative complications.

METHODS

Patients with potentially resectable advanced thoracic oesophageal squamous cell carcinoma were randomized to either postoperative or preoperative chemotherapy followed by transthoracic oesophagectomy with D2-3 lymphadenectomy. Chemotherapy consisted of two cycles of cisplatin and 5-fluorouracil. Clinical baseline data, intraoperative complications, postoperative complications and in-hospital mortality, collected on the case report forms in a predetermined format, were analysed. Univariable and multivariable analyses were used to explore the risk of postoperative complications in relation to treatment group, age, sex, tumour depth, nodal metastasis, stage and location.

RESULTS

Of 330 patients randomized, 166 were assigned to receive postoperative chemotherapy and 164 preoperative chemotherapy; 162 and 154 patients respectively underwent surgery. The incidence of intraoperative complications, postoperative complications and in-hospital mortality was similarly low in both groups. Multivariable analysis showed that age, sex and tumour location were independently associated with an increase in postoperative complications, but preoperative chemotherapy was not.

CONCLUSION

Preoperative chemotherapy does not increase the risk of complications or hospital mortality after surgery for advanced thoracic oesophageal cancer.

A study comparing endoscopic ultrasound (EUS) and computed tomography (CT) in staging oesophageal cancer and their role in clinical decision making

BACKGROUND AND AIM

Computed tomography (CT) and endoscopic ultrasound (EUS) are part of the regular preoperative staging protocol in oesophageal cancer. At present, EUS is increasingly being used for preoperative locoregional staging of oesophageal cancer. The aim of this study is to compare EUS and CT findings and their role in clinical decision making.

METHODS

The CT staging of 30 patients with oesophageal carcinoma was compared with EUS. This is a single centre-based study, and the EUS was carried out by a single operator.

RESULTS

The mean age was 58.2 years. On EUS, one (3.3%), five (16.7%), 16(53.3%) and eight (26.7%) patients had T1, T2, T3 and T4 tumours, respectively, compared with CT which showed 12(40%), nine (30%) and seven (23.3%) patients with T2, T3 and T4 tumours. On CT, two (6.7%) were shown as no tumour (T0). EUS revealed lymph node involvement in 25 (83.3%) patients compared with CT which indicated lymph node involvement in seven (23.3%) patients. On EUS, coeliac node involvement was shown in four (13.3%) patients (M1). The TNM staging of CT and EUS were comparable in nine (30%) patients. EUS staging revealed a more advanced stage of oesophageal cancer in 17 (56.7%) patients. Preoperative EUS staging changed the decision of management in 15 (50%) patients (P < 0.005).

CONCLUSIONS

EUS staging revealed a more advanced stage of cancer in the majority of patients. It appears to be far more superior in detecting lymph node involvement compared with CT. Therefore, EUS may have a significant impact on deciding the treatment modality of a patient with oesophageal carcinoma.

Hedgehog and epithelial-mesenchymal transition signaling in normal and malignant epithelial cells of the esophagus

It has been established that the Hedgehog (Hh) and epithelial-mesenchymal transition (EMT) signals act on morphogenesis of embryonic and adult tissues. Recently, both signals have been involved in tumor malignancy. However, little is known as to whether Hh and EMT signals act on normal and malignant epithelial cells in the esophagus. By laser microdissection (LMD)-based microarray and reverse transcription polymerase chain reaction in the undifferentiated and differentiated epithelial cells of the esophagus, we compared the expression profiles of Hh and EMT signaling molecules of these cells with those of cancers. Whether and how both signalings act in undifferentiated cells and in cancer cells are investigated by treatment of a Hh-signal inhibitor and/or siRNAs of Hh and EMT transcriptional key regulator genes on a mouse primary culture and on human esophageal squamous cell carcinoma (ESCC) cell lines. Undifferentiated esophageal epithelial cells and most ESCCs coexpressed Hh and EMT signaling genes. Some mesenchymal-related genes were regulated by an EMT regulator SIP1/ZEB2/ZFHX1B, which was a downstream gene of a primary transcriptional transducer GLI1 in Hh signaling. Hh signal block inhibited esophageal keratinocyte differentiation and cancer cell invasion and growth. These findings suggest that the mesenchymal gene expression of undifferentiated cells is maintained or strengthened in cancer cells through Hh signaling. This is a first report showing the presence of crosstalk between Hh and EMT pathways.

Mode of lymphadenectomy and surgical outcome of upper thoracic esophageal squamous cell carcinoma

INTRODUCTION

Only a few studies have evaluated the impact of clinicopathological variables and cervical lymphadenectomy on survival in patients with upper thoracic esophageal squamous cell carcinoma (SCC).

MATERIAL AND METHODS

From 1960 to 2005, a total of 167 consecutive patients with upper thoracic esophageal SCC underwent esophagectomy. Of these patients, 108 underwent surgery between 1960 and 1989 and 59 between 1990 and 2005. A total of 65 patients were treated with cervical lymphadenectomy. Univariate and multivariate analyses were performed to evaluate the impact of clinicopathological variables on surgical outcome and possible predictors for cervical lymph node metastasis.

RESULTS AND DISCUSSION

The overall 5-year survival of the later period was significantly better than the former period (43% vs 13%, p < 0.01). Based on Cox's proportional hazards model, T3/T4 tumors, thoracic or abdominal node metastasis, venous invasion, residual cancer, absence of cervical lymphadenectomy, and hospital morbidity were independent risk factors for reduced survival in patients with upper thoracic esophageal SCC. A total of 31 (48%) of 65 patients who underwent cervical lymphadenectomy showed positive nodes in cervical field.

CONCLUSION

Based on logistic regression analysis, T3/T4 tumors and recurrent nerve node metastasis were possible risk factors for cervical node metastasis.

Appraisal of a revised lymph node classification system for esophageal squamous cell cancer

BACKGROUND

Node-positive patients with esophageal carcinoma constitute a heterogeneous population with a variable prognosis, which the current staging system insufficiently addresses. To that end, 863 patients with a curative resection for esophageal squamous cell carcinoma were analyzed to evaluate a useful and simple nodal classification system.

METHODS

Along with standard conventional clinicopathologic factors, data for metastatic lymph node (MLN) number, metastatic to examined LN ratio (MLN ratio), and MLN size were evaluated. The greatest microscopic dimension of the metastatic tumor inside the largest MLN (MLN size) was measured on histopathologic slides. Patients with MLNs were classified into n1 (< 9 mm) and n2 (> or = 9 mm) groups, according to size of MLNs (n-stage).

RESULTS

The paratracheal LNs most frequently contained the largest MLN and among them the right recurrent laryngeal LNs were the most common site (81.8%). Patients were stratified into significant groups by all the nodal criteria. In multivariable analysis, MLN size n-stage and MLN ratio N-stage were the best independent predictors for disease-free and overall survival, respectively. In the disease-free survival, MLN ratio N-stage subcategories were divided into prognostic groups according to the n-stage. A combined nodal staging strategy combining the n-stage and N-stage had the strongest prognostic value and was used for the tumor-node-metastasis classification with distinct separation of patients into prognostic groups.

CONCLUSIONS

Results of this study indicate that the MLN size may serve as an accurate metric to classify node-positive patients and a combination of the MLN ratio and size may have synergism in classifying node-positive patients into prognostically homogenous groups.

New insights in the lymphatic spread of oesophageal cancer and its implications for the extent of surgical resection

In this review new insights in the dissemination pattern of oesophageal tumours and the implications for the (extent of) surgical and endoscopic resection are discussed. Moreover, the sentinel node concept in oesophageal cancer is reconsidered. Three-years survival after a limited resection for cervical-upper thoracic oesophageal cancer was 14-20% after an extended resection. No patients with distant metastases were alive after five years. Therefore, curative surgery for cervical-upper oesophageal cancer with extended lymph node dissection is probably only indicated in patients without distant lymph nodes metastases. Involved coeliac nodes can be found in tumours of the whole oesophagus. Adenocarcinomas of the gastrooesophageal junction do metastasize predominantly to the paracardial and lesser curvature regions. No significant difference was found in a randomized trial comparing two-field transthoracic resection with limited transhiatal resection for adenocarcinoma of the gastrooesophageal junction.(6) Subgroup analysis for patients with a distal oesophageal adenocarcinoma revealed a 17% survival benefit after transthoracic resection. In several Japanese studies a better five-year survival is claimed after a three-field lymph node dissection than after a conventional two-field lymphadenectomy. In a randomized study, however, no statistically significant difference was found in the short- and long-term survival nor in the recurrence rate. If an early lesion is limited to the mucosa, endoscopic mucosal resection (EMR) could be considered because of the low chance of lymph node metastases. However, the technique of EMR has not yet been optimized resulting in high numbers of local cancer recurrences and a high need for endoscopic re-resections. Only few studies investigated whether the sentinel node concept is applicable to the oesophagus or gastric cardia. In one study in patients with oesophageal or cardia cancer, the accuracy was 96% and only two false negative sentinel nodes were identified. The sentinel node concept in oesophageal cancers might change future operative strategies.