Dagli Adile Ferda, Pehlivan Sultan, Ozercan Melhmet Resat
Department of Pathology, Medical School, Firat University, Elazig, Turkey.
Acta Cytol. 2010 Jul-Aug;54(4):601-4. doi: 10.1159/000325185.
Primary pleural liposarcoma is extremely rare, and its most common subtype is the myxoid subtype. To the best of our knowledge, the number of cases reported up to now is <20. It is primarily a disease ofindividuals 50 years of age and it is more common in men. It has no specific symptoms except for cough and chest pain.
A 56-year-old female presented complaining of chest pain and dyspnea for 4 months. An increase in homogeneous density on the left hemithorax, from the apex to basal area, with blurring of the borders of the heart and the diaphragm, was revealed by lung radiography. Thoracic computed tomography revealed a diffuse pleural effusion causing compressive atelectasis at the base of the left hemithorax. Cytologic examination of the pleural fluid demonstrated tumoral cells forming papillary structures with complex branching and fine fibrovascular core. The tumor cells were relatively uniform and had vacuolar cytoplasm with hyperchromatic nuclei. Upon finding CA-125 positive in the immunocytochemical examination, the case was reported as "consistent with malignancy, possibility of ovarian origin, cannot be excluded". As the gynecologic examination was normal, exploratory thoracotomy was performed to take a biopsy. The case was diagnosed as liposarcoma (myxoid type) by histopathologic examination.
Cytologic diagnosis of pleural liposarcoma is difficult due to its rarity and resemblance to malignant mesothelioma. Cytologic properties of liposarcoma in pleural fluid should be well known and considered in the differential diagnosis.
原发性胸膜脂肪肉瘤极为罕见，其最常见的亚型为黏液样亚型。据我们所知，截至目前报道的病例数<20例。它主要是一种50岁人群的疾病，在男性中更为常见。除咳嗽和胸痛外，它没有特异性症状。
一名56岁女性因胸痛和呼吸困难4个月前来就诊。胸部X线检查显示左半胸从肺尖到肺底均匀密度增加，心脏和膈肌边界模糊。胸部计算机断层扫描显示弥漫性胸腔积液，导致左半胸底部压迫性肺不张。胸腔积液的细胞学检查显示肿瘤细胞形成具有复杂分支和细纤维血管核心的乳头状结构。肿瘤细胞相对均匀，具有空泡状细胞质和核深染。免疫细胞化学检查发现CA-125阳性，该病例报告为“符合恶性肿瘤，可能起源于卵巢，不能排除”。由于妇科检查正常，遂行剖胸探查活检。经组织病理学检查，该病例诊断为脂肪肉瘤（黏液样型）。
由于胸膜脂肪肉瘤罕见且与恶性间皮瘤相似，其细胞学诊断困难。在鉴别诊断中应充分了解并考虑胸腔积液中脂肪肉瘤的细胞学特征。
