7．肺尖部胸壁浸潤癌の手術

Surgical Treatment for Apical Invading Lung Cancer

肺尖部胸壁浸潤癌は，胸郭上口（thoracic inlet）において第1肋骨かそれ以上頭側の胸壁に浸潤する肺癌である1）．このうちsuperior sulcusより背側に位置し，肩から上肢内側へ広がる痛み，手の筋肉の萎縮，Horner症候群を呈するものをsuperior pulmonary sulcus tumor（狭義のsuperior sulcus tumor）としてPancoastが報告した2）．Superior sulcusより腹側に位置するものはanterior apical tumorと呼ばれ1），二つを併せてsuperior sulcus tumorと総称されている．

The apical invading lung cancer is the tumor infiltrating to the thoracic inlet, in other words, the 1st rib or the higher chest wall. Tumor arising in the posterior apex is invasive to the vertebral body, the sympathetic trunk, and the brachial plexus. Pancoast tumor is well known with typical triads, which is invasive to the sympathetic trunk and the brachial plexus in the posterior apex of the lung. Tumors originating in the anterior apex are called anterior apical tumors, and they often involve the subclavian vein and artery. Trimodality therapy is recommended to treat the apical invading lung cancer. Induction chemoradiotherapy followed by surgical resection lead to good local control and complete resection rate. Surgical approach should be selected based on the tumor location in the extreme apex. High posterolateral approach and hook approach are chosen for the tumor in the posterior apex. Anterior approaches developed by Masaoka, Dartevelle, Grunenwald, and Korst are suitable for the tumor in the anterior apex that are often invasive to the subclavian vessels. Surgical outcome depends on completeness of resection. Based on the preoperative evaluation of involved structures, appropriate surgical approach is important to achieve complete resection of the apical invading lung cancer.