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Role of 3D reconstruction in the evaluation of patients with lower segment oesophageal cancer.

Background
Three-dimensional (3D) reconstruction has been used in evaluating the lungs and liver, but there is only little research on the application of 3D reconstruction for the oesophagus. This research aims to study the application of 3D reconstruction in patients with lower segment oesophageal tumours to improve the diagnosis and treatment of oesophageal cancer and to provide a better method of preoperative assessment.


Methods
All the patients were treated at the First Hospital of Jilin University between January 2014 and August 2015 for oesophageal cancer. We collected the patients' imaging data and used surface reconstruction technology to reconstruct their oesophageal tumours and adjacent structures. Tumour shape and other specific parameters were analysed and calculated, and comparisons of the results from different conditions of 3D reconstruction were made. IBM SPSS 19.0 was used to analyse all the data. All the data were averaged over three measurements. The t-test was used to compare the mean of the two groups, and variance analysis was used among the groups, where P<0.05 indicated a significant difference.


Results
Of the 72 patients, there were 48 cases in which a gastroscope was able to pass through the oesophageal lesion and 24 cases where this was not possible. The location of the lesion ranged from 30 to 42 cm among those 48 cases. The endoscopic measurement length and the 3D length were both longer than the pathological length (P<0.05), but there was no significant difference between the endoscopic measurement length and the 3D length. In the reconstructed data of positive lymph nodes, the length, diameter, volume, CT value and reconstruction of the lymph nodes in the negative group were significantly different compared with the positive group.


Conclusions
The application of 3D reconstruction in oesophageal cancer is safe and effective. 3D reconstruction plays an important role in preoperative evaluation of tumours and the surrounding lymph nodes and may be useful for evaluation of the long-term efficacy of radiotherapy and chemotherapy for oesophageal cancer.