Zheng Zhi, Pan Youmin, Guo Fengwei, Wei Hao, Wu Shimin, Pan Tiecheng, Li Jun
Department of Cardiothoracic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, PR China.
South Med J. 2011 Jun;104(6):440-5. doi: 10.1097/SMJ.0b013e318218700a.
Differentiation between pulmonary tuberculoma and malignancy by preoperative diagnostic imaging sometimes proves difficult. The purpose of this study is to investigate variable manifestations of pulmonary tuberculoma mimicking lung cancer on fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) image and pathologic correlation.
Twenty-five patients with a high suspicion of malignancy and histopathologically diagnosed as pulmonary tuberculoma were included. Their FDG PET/CT images, clinical data, and pathologic findings were investigated.
There were 18 men and seven women. The mean age was 52 ± 8.8 years. The maximal diameter of pulmonary tuberculoma ranged from 1.7 to 4.2 cm. CT scan revealed that abnormal signs associated with malignancy such as spicular radiation, notching, and pleural indentation also frequently manifested in tuberculoma. During early imaging, positive FDG uptake was identified in 21 patients (84%), intermediate uptake in 3 patients (12%) and negative uptake in 1 patient (4%). During delayed imaging, 16 patients (64%) showed persistent elevated FDG accumulation and 8 patients (32%) experienced a slight drop of FDG accumulation. Pathologically active tuberculoma showed significantly higher FDG radioactivity during both early and delayed imaging than inactive lesion (P < 0.05). Lymphadenopathy with positive FDG uptake was identified in nine patients (36%).
Pulmonary tuberculomas mimicking lung cancer, most of which were pathologically active lesions, commonly displayed abnormal appearances in CT scan and an increase in FDG uptake, similar to changes seen on malignancy. Coexistent lymphadenopathy made differential diagnosis even more complicated. These results suggested that positive FDG PET/CT findings should be interpreted with caution in tuberculosis-endemic regions.
术前诊断性影像学检查有时难以区分肺结核球与恶性肿瘤。本研究旨在探讨氟脱氧葡萄糖（FDG）正电子发射断层扫描/计算机断层扫描（PET/CT）图像上模仿肺癌的肺结核球的多种表现及其病理相关性。
纳入25例高度怀疑为恶性肿瘤且经组织病理学诊断为肺结核球的患者。对其FDG PET/CT图像、临床资料及病理结果进行研究。
男性18例，女性7例。平均年龄为52±8.8岁。肺结核球的最大直径为1.7至4.2厘米。CT扫描显示，肺结核球也常出现与恶性肿瘤相关的异常征象，如毛刺状放射、切迹和胸膜凹陷。早期成像时，21例患者（84%）FDG摄取呈阳性，3例患者（12%）摄取中等，1例患者（4%）摄取阴性。延迟成像时，16例患者（64%）FDG积聚持续升高，8例患者（32%）FDG积聚略有下降。病理上有活性的结核球在早期和延迟成像时的FDG放射性均显著高于无活性病变（P<0.05）。9例患者（36%）发现有FDG摄取阳性的淋巴结肿大。
模仿肺癌的肺结核球，其中大多数为病理活性病变，在CT扫描中通常表现为异常外观，且FDG摄取增加，类似于恶性病变所见。并存的淋巴结肿大使鉴别诊断更加复杂。这些结果表明，在结核病流行地区，对FDG PET/CT阳性结果应谨慎解读。
