Urban T
Pôle Thorax Vaisseaux, CHU Angers, France.
Rev Mal Respir. 2007 Jun;24(6):725-40. doi: 10.1016/s0761-8425(07)91147-x.
Pulmonary lymphangioleiomyomatosis (LAM) is a rare disease affecting young women and presenting with recurrent pneumothorax.
Other lesions such as chylothorax or renal angiomyolipoma may suggest the diagnosis. The condition is related to a proliferation of abnormal smooth muscle cells staining for the monoclonal antibody HMB45. LAM can appear sporadically or be associated with tuberous sclerosis with abnormalities of the TSC2 suppressor gene. High resolution thoracic CT scanning shows bilateral, thin walled pulmonary cysts. Pulmonary function tests reveal bronchial obstruction and over-inflation with a reduced DLCO being the earliest abnormality.
Although there are non-progressive forms, LAM usually leads to chronic respiratory insufficiency within a few, or ten or so years. In the absence of a controlled clinical trial hormone therapy has not been shown to be effective. Lung transplantation is the last therapeutic resort; recurrences in the transplanted lung have been occasionally reported.
Analysis of the molecular mechanisms induced by mutations of the TSC2 suppressor gene and the demonstration of the migratory properties of smooth muscle cells, whose origin may be extra-thoracic, reveal new specific antiproliferative therapeutic options.
肺淋巴管平滑肌瘤病(LAM)是一种罕见疾病,影响年轻女性,表现为反复气胸。
其他病变如乳糜胸或肾血管平滑肌脂肪瘤可能提示诊断。该疾病与对单克隆抗体HMB45染色的异常平滑肌细胞增殖有关。LAM可散发出现或与结节性硬化症相关,伴有TSC2抑癌基因异常。高分辨率胸部CT扫描显示双侧薄壁肺囊肿。肺功能测试显示支气管阻塞和过度充气,DLCO降低是最早出现的异常。
尽管存在非进行性形式,但LAM通常在数年或十年左右导致慢性呼吸功能不全。在缺乏对照临床试验的情况下,激素治疗尚未显示有效。肺移植是最后的治疗手段;偶尔有移植肺复发的报道。
对TSC2抑癌基因突变诱导的分子机制的分析以及平滑肌细胞迁移特性的证明,其起源可能在胸外,揭示了新的特异性抗增殖治疗选择。