Siminovich Mónica, Galluzzo Laura, López Jessica, Lubieniecki Fabiana, de Dávila María Teresa G
Department of Pathology, Hospital Nacional de Pediatría J. P Garrahan, Buenos Aires, Argentina.
Pediatr Dev Pathol. 2012 May-Jun;15(3):179-86. doi: 10.2350/11-10-1105-OA.1. Epub 2012 Jan 26.
The inflammatory myofibroblastic tumor (IMT) is a rare neoplastic lesion with a high incidence in children and young people, and may arise in lungs, soft tissue, or viscera. It is recognized as a borderline tumor with the possibility to recur, undergo malignant transformation, and metastasize. IMT is composed of fascicles of bland myofibroblastic cells admixed with an inflammatory infiltrate consisting of lymphocytes, plasma cells, and eosinophils. We reviewed pulmonary IMT diagnosed at Garrahan Hospital in Buenos Aires, Argentina, during 12 years and examined the clinical, laboratory, and pathological features as well as molecular genetics. Eight pediatric cases were evaluated with a male-to-female ratio of 5:3 and a median age of 6 years at diagnosis. The most common lung localization was the upper lobe. All cases underwent surgical excision and no local recurrences were found. Five out of eight patients, including two cases with metastatic/multifocal lesions in the central nervous system (CNS), are alive and disease free after a median follow-up of 30 months. Anaplastic lymphoma kinase (ALK) expression was negative in all pulmonary samples by immunohistochemistry (IHC), however, rearrangement for ALK locus by fluorescence in situ hybridization was found in one lung and in two CNS samples. These findings may reflect higher sensitivity of the molecular biologic procedure compare to traditional IHC practice. In our pediatric experience, 25% of patients with lung IMT developed CNS lesions; therefore we consider that CNS screening in these patients should be considered, at diagnosis and later during follow up.
炎性肌纤维母细胞瘤（IMT）是一种罕见的肿瘤性病变，在儿童和年轻人中发病率较高，可发生于肺、软组织或内脏。它被认为是一种交界性肿瘤，有可能复发、发生恶性转化和转移。IMT由温和的肌纤维母细胞束组成，并伴有由淋巴细胞、浆细胞和嗜酸性粒细胞组成的炎性浸润。我们回顾了阿根廷布宜诺斯艾利斯加拉汉医院12年间诊断的肺IMT病例，并研究了其临床、实验室和病理特征以及分子遗传学。评估了8例儿科病例，男女比例为5:3，诊断时的中位年龄为6岁。最常见的肺部定位是上叶。所有病例均接受了手术切除，未发现局部复发。8例患者中有5例存活，包括2例中枢神经系统（CNS）有转移/多灶性病变的病例，中位随访30个月后无疾病。免疫组织化学（IHC）检测显示所有肺组织样本中间变性淋巴瘤激酶（ALK）表达均为阴性，然而，通过荧光原位杂交发现1例肺组织样本和2例CNS样本中有ALK基因座重排。这些发现可能反映了分子生物学检测方法相对于传统IHC方法具有更高的敏感性。根据我们在儿科的经验，25%的肺IMT患者会出现CNS病变；因此，我们认为在这些患者的诊断和随访期间应考虑进行CNS筛查。
