Yasunori Sohara

Identification of the transforming EML4–ALK fusion gene in non-small-cell lung cancer

Improvement in the clinical outcome of lung cancer is likely to be achieved by identification of the molecular events that underlie its pathogenesis. Here we show that a small inversion within chromosome 2p results in the formation of a fusion gene comprising portions of the echinoderm microtubule-associated protein-like 4 (EML4) gene and the anaplastic lymphoma kinase (ALK) gene in non-small-cell lung cancer (NSCLC) cells. Mouse 3T3 fibroblasts forced to express this human fusion tyrosine kinase generated transformed foci in culture and subcutaneous tumours in nude mice. The EML4–ALK fusion transcript was detected in 6.7% (5 out of 75) of NSCLC patients examined; these individuals were distinct from those harbouring mutations in the epidermal growth factor receptor gene. Our data demonstrate that a subset of NSCLC patients may express a transforming fusion kinase that is a promising candidate for a therapeutic target as well as for a diagnostic molecular marker in NSCLC.

Descending necrotizing mediastinitis secondary to retropharyngeal abscess without cervical spread.

Cervical infections can cause neck phlegmonosa and occasionally develop lethal mediastinitis. We report a 52-year-old man with a retropharyngeal abscess causing descending mediastinis without cervical spread. Thoracoscopic drainage without cervicotomy was successful. Deep neck infections causing a descending mediastinitis should be considered in patients even without an abnormal neck appearance.

A dangerous venous variation in thoracoscopic right lower lobectomy.

Anatomical variations of the pulmonary vessels present a potential risk of intraoperative bleeding and damage to pulmonary circulation during pulmonary resection. We present details of a dangerous variation of the superior pulmonary vein associated with thoracoscopic right lower lobectomy that could potentially be divided if there was no preoperative foreknowledge of individual vessel configurations.

Spontaneous regression of symptomatic thymoma caused by infarction

We herein report a 38-year-old man who had spontaneous regression of a thymoma with repeating episodes of chest pain that initially occurred 2 years earlier when the tumor was 35 mm in the long axis. Left video-assisted thoracoscopic thymothymectomy was performed. Pathology examination showed a thymoma 15 mm in the long axis, classified B2 in the World Health Organization classification and stage II by Masaoka staging. The feeding arteriole of the tumor, occluded by organized thrombi, was suggested to be the cause of coagulation necrosis. The patient recovered well from surgery without complication and with no episodes of chest pain at the 9-month outpatient follow-up.

Large-cell neuroendocrine carcinoma without immunohistological positivity or serum elevation of CEA until relapse

We herein report a case of large cell neuroendocrine carcinoma (LCNEC) originating in the right lung upper lobe and showing unique features at relapse in the right middle lobe. The relapsed tumor pathology included a carcinoembryonic antigen (CEA)-positive mantle component and a CEA-negative core area. The latter showed the same pathological picture as the original tumor, both histologically and immunohistochemically. The serum CEA concentration did not increase until the tumor relapsed, and it fell to within the normal range after resection of the relapsed tumor. Rarely, a newly elevated tumor marker suggests relapse, even in resected cases with a negative immunohistochemical study for the marker.

Epithelioid sarcoma arising in the thoracic wall. A case report.

背部胸壁に原発した類上皮肉腫の1例を報告した.患者は64歳男で胸壁腫瘤を主訴に来院.胸部CTで左脊柱起立筋内に石灰化を伴う腫瘤を認めた.穿刺吸引細胞診では大型類円形ないし多稜形異型細胞よりなる結合性の疎な細胞集塊や少数の紡錘形細胞がみられた.摘出された腫瘍は白色充実性分葉状で, 一部で出血や中心壊死を伴い, 辺縁では骨化がみられた.組織学的には多稜形細胞が上皮様胞巣を形成する部分と紡錘形腫瘍細胞からなり, 両者はなだらかに移行していた.一部でrhabdoid featureを呈していた.免疫組織化学的にはCAM 5.2陽性, EMA陽性, CEA陽性, vimentin陽性, HHF35陽性, α-smooth muscle actin陽性, NSE陽性, desmin陰性, S-100陰性, factor VIII陰性であった.電顕的には細胞質に豊富な中間径細線維がみられた.