Haruhiko Ishii

Hepatoid adenocarcinoma in the lung

We have experienced a very rare case of hepatoid adenocarcinoma in the lung. A 55-year-old male with a history of smoking was diagnosed as adenocarcinoma of the right S2, and underwent resection of the right upper lobe and dissection of the hilum and mediastinal lymph nodes (complete resection). Pathological examination revealed cuboid atypical cells arranged in a papillary or trabecular fashion, and a proliferating pattern in most part of the tumor resembling that of hepatocellular carcinoma. Immunohistochemistry study showed alpha-fetoprotein (AFP)-positive tumor cells, hence the diagnosis of hepatoid adenocarcinoma was confirmed. Postoperative pathological staging classified the patient as having as p-T2NOMO, p-stage I B disease. The serum AFP level was not determined before surgery, but the value decreased gradually after surgery and has since remained within the normal range. At present, 32 months after the operation, no signs of recurrence have been observed. Hepatoid adenocarcinoma in the lung has been reported in eight patients with the present one being the ninth case. All were males, the tumor diameter was large and the patient prognoses were mostly poor, but at early stage two cases of long-term survival have been reported indicating that the stage is the most important prognostic factor also for rare tumor.

Colliding primary lung cancers of adenosquamous carcinoma and large cell neuroendocrine carcinoma

We report an extremely rare case of primary lung cancer showing various histological elements diagnosed as the collision of an adenosquamous carcinoma and a large cell neuroendocrine carcinoma by loss of heterozygosity (LOH) analysis of the human androgen receptor (AR) and phosphoglycerate kinase (PGK‐1) genes. The tumor exhibited a tiny ground‐glass opaque shadow suggesting atypical adenomatous hyperplasia 18 months prior to surgery. However, the tumor grew rapidly, and the resected tumor consisted of two closely located nodules. The larger nodule was composed of well‐differentiated adenocarcinomatous and moderately to poorly differentiated squamous cell carcinomatous elements, while the smaller nodule consisted of a large cell neuroendocrine carcinomatous element with partial squamoid differentiation having focal continuity with the adenocarcinomatous element. Both the adenocarcinomatous and squamous cell carcinomatous elements revealed transitional features and LOH of AR and PGK‐1 genes, while the large cell neuroendocrine carcinomatous element showed a monoclonal pattern but possessed both alleles of AR and PGK‐1 genes. From these clinical and pathological results, the parental cell of the large cell neuroendocrine carcinomatous element was considered to be different from that of the adenosquamous carcinomatous element.

Computed Tomography Imaging Analysis of Resected Lung Cancers Detected by Computed Tomography.

最近約3年間に神奈川県立がんセンターで切除された原発性肺癌240例の中で, 通常の胸部単純X線写真ではその原発巣の指摘が困難でX線CT検査を契機に発見された肺野型肺癌30例について, CT画像および病理所見をretrospectiveに解析した.内訳は男性16例, 女性14例であり, 年齢は39～79 (中央値66) 歳であった.発見動機は自覚症状を有した例は5例のみであり, 他疾患経過中が8例, 残りは検診を目的としてCTが施行された.CT画像は淡い低濃度型と辺縁明瞭な充実型に大別され, 前者では病変と既存肺野との濃度差が少ないことが, 後者では肺門部の血管, 心臓および骨組織との重なりによりX線写真では病変の描出が困難であった.病理所見は25例 (83%) が1期であり, うち低濃度型例が21例 (70%) を占めた.以上よりCTで発見された肺癌, 特に低濃度型例は早期肺癌が多く, CT検査の検診への導入と低濃度型例の発見が治癒する肺癌の発見につながることが示唆された.