Objectives: Hypopharyngeal cancer (HPC) and cervical esophageal cancer (Ce) are aggressive tumors with a poor prognosis. Multiple lymph node metastases often occur in the upper mediastinum, as well as in the neck, and thus upper mediastinal dissection (MD) is crucial to improving the cure rate. However, excessive MD can increase postoperative morbidity and mortality, making it important to employ the proper technique and appropriate extent of dissection. In the present retrospective study we aimed to determine the proper extent of upper MD according to tumor site and stage. The benefit and risk of upper MD are also discussed.
Methods: Chart review was completed for patients who underwent upper MD, including 64 patients with HPC, 21 patients with Ce, and 9 patients with Ce extending to involve the upper thoracic esophagus (Ce/Ut). The incidence and distribution of lymph node metastases in the upper mediastinum were assessed by postoperative histopathologic examination. Postoperative complications of upper MD, as well as the impact on survival and locoregional control, were also reviewed.
Results: Upper mediastinal metastases were detected in 7.8% of HPC patients, 33.3% of Ce patients, and 55.6% of Ce/Ut patients. In HPC patients, mediastinal metastases were usually associated with T4 primary tumors (80%), whereas positive nodes in the upper mediastinum were detected regardless of T stage in both Ce and Ce/Ut. Only 1 Ce/Ut patient with a T4 tumor developed late nodal metastasis in the lower mediastinum. The 5-year disease-specific survival and locoregional control rates were 58.6% and 90.2% in HPC, 45.5% and 94.1% in Ce, and 38.9% and 77.7% in Ce/Ut, respectively. Rupture of the greater vessels after MD was observed in 5 cases (5.3%).
Conclusions: The present results indicate excellent locoregional control rates following upper MD, while major complications such as arterial breakdown were rare. It is suggested that upper MD may be an essential and adequate procedure for patients with Ce or Ce/Ut tumors, and may also be required for cases of HPC with a T4 primary to improve locoregional control of the disease.