Failure Patterns after Radical Surgery of Thoracic Esophageal Squamous Carcinoma

Abstract

Radiation therapy is an important cancer treatment modality in both adjuvant and definitive setting, however, the use of radiation therapy for elective treatment of regional lymph nodes is controversial for esophageal squamous cell carcinoma after radical surgery. This analysis aims to study the metastasis pattern through a pooled analysis of published results after radical tumor and lymph nodal resection with histological study in thoracic esophageal squamous cell carcinoma. Literature search using electronic databases of MEDLINE from May 1977 to April 2017 was performed, supplemented by review of references. Thirteen researches and 2531 thoracic esophageal squamous cell carcinoma patients underwent radical surgical resection were included. The probability of recurrence and metastasis in local (anastomotic and tumor bed included), lymph node and distal area was calculated. A chi-square test was used to investigate the difference by statistical software. The recurrent rate is 24.45% for locoregional, 13.23% for distal, 22.24% for lymph node, 2.44% for local. Lymph nodes is divided into cervical and supraclavicular with the recurrent rate of 12.27%, mediastinal with rate of 18.69%(upper 28.23%, middle 17.90% and lower 5.27%, respectively) and abdominal with rate of 6.10% (paraaortic 5.95% and upper abdominal 4.01% respectively). In upper thoracic esophageal squamous cell carcinoma, the order is as follows, cervical and supraclavicular with of 24.32%, mediastinal with rate of 14.86% (upper mediastinal 9.38%, middle mediastinal 3.131%, lower mediastinal 3.13%), abdominal with rate of 1.56%. In middle thoracic esophageal squamous cell carcinoma, the order is as follows, mediastinal with rate of 11.19%(upper mediastinal 7.36%, middle mediastinal 1.74%, lower mediastinal 1.74%), cervical and supraclavicular with rate of 7.12%, and abdominal with rate of 4.75%. In lower thoracic esophageal squamous cell carcinoma, the order is as follows, abdominal LN with rate of 14.85% (paraaortic 11.39% and upper abdominal 3.47%), mediastinal LN with rate of 6.93% (upper mediastinal LN 2.79%, middle mediastinal 1.68%, lower mediastinal LN 1.68%), and cervical and supraclavicular with rate of 3.47% The distal metastatic pattern is as follows, lung (7.04%), liver (6.79%), bone (4.99%), skin (2.28%), and brain (0.74%). Thoracic esophageal squamous cell carcinoma has a high propensity of lymphatic metastases but poor propensity of anastomotic and tumor bed recurrence. Cervical and supraclavicular, upper mediastinal should be delineated as the postoperative prophylactic irradiation target volume for upper, cervical and supraclavicular, upper mediastinal and abdominal lymph nodes especially paraaortic for middle, abdominal lymph nodes especially paraaortic and mediastinal lymph nodes should be delineated for lower as the postoperative prophylactic irradiation target volume.