A Case of Resected Pulmonary Liposarcoma with Hamartoma

━━ Background. Liposarcoma most commonly arises in the extremities and retroperitoneum. Primary pulmonary liposarcoma is rare and there are very few cases accompanied by hamartoma. Case. A 62-yearold man was referred to our hospital because of an abnormal shadow on a chest X-ray film which showed decreased translucency in the left lower lung field. Chest CT and MRI showed a huge heterogeneous tumor with fat and soft tissue components expanding into the left thoracic cavity, suggesting liposarcoma. We attempted to perform tumor resection, however, the tumor was suspected to invade adjacent organs, thus we performed complete resection of the tumor with combined resection of the left lung and pericardium. The tumor was 21×15×8.5 cm in size. Histologically, most of the tumor consisted of a well-differentiated liposarcoma, except for some small white nodules diagnosed as hamartomas. No adjuvant therapy was performed and the patient has been well without recurrence for 2 years after the surgery. Conclusion. We described a rare case of completely resected primary pulmonary liposarcoma associated with hamartoma. Surgically complete resection is recommended for well-differentiated liposarcoma because of its good prognosis after surgery. (JJLC. 2012;52:890-896) KEY WORDS━━ Liposarcoma, Mediastinal tumor, Hamartoma, Pulmonary liposarcoma Reprints: Miyuki Kitahara, Department of Thoracic Surgery, Ibaraki Prefectural Central Hospital and Cancer Center, 6528 Koibuchi, Kasama-city, Ibaraki 309-1793, Japan (e-mail: m-kitahara@chubyoin.pref.ibaraki.jp). Received January 17, 2012; accepted August 10, 2012. 要旨━━背景.脂肪肉腫は四肢や後腹膜にしばしば発 生するが,肺内発生および過誤腫共存例は稀である.症 例.62 歳男性.健診で胸部異常陰影を指摘され,精査加 療目的に当院を受診した.初診時の胸部X線写真では, 左下肺野全体の透過性低下を認めた.胸部CTおよび MRI では,左胸腔内を広汎に占拠する内部不均一で脂肪 成分を含む腫瘍を認めた.画像所見より,脂肪肉腫が疑 われた.手術は左後側方切開で行い腫瘍切除術を予定し た.しかし,腫瘍は左肺,心嚢および肺門の脂肪織と連 続し正常脂肪織との境界が不明瞭であった.また,上下 肺静脈と密に癒着していたため,左肺全摘・心膜合併切 除術を施行し腫瘍の完全切除を行った.腫瘍は大きさ 21×15×8.5 cm,組織学的には腫瘍の大半を占める領域 は分化型脂肪肉腫と診断され,一部白色結節領域は過誤 腫と診断された.術後補助療法なく 2年経過するが再発 は認めていない.結論.左肺全摘および心膜合併切除に より完全切除し得た,過誤腫が共存する肺内脂肪肉腫の 1例を経験した.分化型脂肪肉腫は外科的治療により良 好な予後が期待できるため,完全切除を目指すことが重 要である. 索引用語━━脂肪肉腫,縦隔腫瘍,過誤腫,肺内脂肪肉 腫 茨城県立中央病院・茨城県地域がんセンター 1呼吸器外科,2病理 科;3雪谷大塚クリニック. 別刷請求先:北原美由紀,茨城県立中央病院・茨城県地域がん センター呼吸器外科,〒309-1793 茨城県笠間市鯉渕 6528(e-mail: m-kitahara@chubyoin.pref.ibaraki.jp). 受付日:2012 年 1 月 17 日,採択日:2012 年 8 月 10 日. (肺癌.2012;52:890-896) 2012 The Japan Lung Cancer Society A Case of Resected Pulmonary Liposarcoma with Hamartoma―Kitahara et al Japanese Journal of Lung Cancer―Vol 52, No 6, Oct 20, 2012―www.haigan.gr.jp 891 Table 1. Laboratory Data on the First Visit Hematology Serology WBC 8900/μl CRP 0.45 mg/dl RBC 5.28×106/μl Hb 15.8 g/dl Tumor markers Ht 46.3% CEA 1.0 ng/ml Plt 384×103/μl AFP 3.4 ng/ml CA19-9 3.4 U/ml Biochemistry TP 8.0 g/dl Arterial blood gas (room air) Alb 4.6 g/dl pH 7.385 T-Bil 0.7 mg/dl PaO2 84.4 torr AST 21 IU/l PaCO2 43.1 torr ALT 20 IU/l HCO325.2 mEq/l LDH 175 IU/l ALP 270 IU/l Respiratory function CK 141 U/l VC 3.25 l ChE 296 U/l %VC 92.3% BUN 13 mg/dl FEV1.0 2.71 l Cr 0.68 mg/dl FEV1.0% 81.4% Na 142 mEq/l K 3.8 mEq/l Cl 102 mEq/l Ca 9.5 mg/dl FBS 102 mg/dl Figure 1. Chest X-ray film on the first visit shows decreased translucency of the left lower lung field. Figure 2. Chest X-ray taken at the medical check up 1 year ago shows a small abnormal shadow. はじめに 脂肪肉腫は,軟部組織由来の非上皮性悪性腫瘍で四肢 や後腹膜にしばしば発生するが,肺内発生は稀であり, また,過誤腫を共存した脂肪肉腫の報告はほとんどない. 今回我々は,過誤腫より発生し,縦隔内に増殖したと考 えられた脂肪肉腫の 1例を経験したので,文献的考察を 加え報告する.