Définition du volume cible anatomoclinique pour l’irradiation des cancers de l’œsophage

Influence of negative lymph node in No 7 on survival of patients with middle thoracic esophageal squamous cell carcinoma

Background

The overall survival (OS) of patients with thoracic esophageal cancer is poor because of the high rate of lymph node metastases. However, recent studies found that the negative lymph node (LN) may also influence the patients’ OS. The purpose of this study is to investigate which negative LN stations play a key role in OS prediction.

Method

Our study included the retrospective records of 99 patients, who were identified with middle thoracic esophageal squamous cell cancer after esophagectomy. The maximum follow-up time was 6 years. Cox regression models were employed to determine the association between the negative LN and OS of patients. After applying Kaplan–Meier method to calculate OS of patients with positive and negative LNs, the log-rank tests were used to assess the difference between them.

Result

The hazard ratio of the total number of negative LNs was 0.937 (P=0.001), and the length of tumor was 1.166 (P=0.038). Multivariate regression results showed that the numbers of positive LNs in No 3 and 7 stations and negative LNs in No 109 and 7 stations were significantly related to OS, and their P-values were 0.017, 0.001, 0.020, and 0.022, respectively. The OS of the patients who had positive and negative LNs in No 7 station was significantly different (P=0.028).

Conclusion

No 7 is the most important among the negative LN stations which prolong OS. More attention should be paid to this area when making treatment plan for patients with no negative LNs identified in operation.

[Are extensive fields useful for radiotherapy of esophageal cancer?]

PURPOSE

Study of the pattern of relapse for locally advanced oesophageal cancer and analysis of the local recurrences according to irradiated volume.

PATIENTS AND METHODS

We performed a monocentric retrospective study of patients treated in the integrated centre of oncology (Angers, France). Two treatment strategies were used: concurrent chemoradiation alone or followed by surgery. Recurrences were classified as: locoregional, either isolated or associated with distant metastasis, and metastatic only. Locoregional relapses were subclassified as in-field, out-field, or mixed.

RESULTS

Between March 2004 and October 2011, 168 patients were treated: 130 by chemoradiation, and 38 by chemoradiation followed by surgery. The median supero-inferior margins added to the gross tumour volume in order to create the planning tumour volume was 5cm (range: 0.5-21). Sixty-two percent of patients (n=104) relapsed: 82 locoregional relapses (49%), including 45 isolated relapses (27%) and 37 associated with distant metastasis relapses (22%), and 22 metastatic relapses (13%). From the 82 locoregional relapses, only four isolated relapses were exclusively out-field.

CONCLUSION

With 5cm supero-inferior margins added to gross tumour volume, less than 3% of patients had an isolated out-field recurrence. However, half of the patients suffered in-field local recurrence and one third had metastases. These findings advocate for a limited prophylactic nodal irradiation. Trials are ongoing to assess dose escalation or surgery in order to increase local control.

[Lymph nodes of esophagus cancer: radiological approach]

The cervico-thoracic-abdominal-pelvic CT-scan is a key examination of the staging of esophagus cancers. Anatomical and pathophysiological knowledge of the lymph nodes is an essential tool to establish a precise mapping. Imaging tests (such endoscopic ultrasound and PET scanning) will be very useful to determine clinical options and clinical target volume delineation for the radiotherapy of esophagus cancers.