Giannaki Alexandra, Doganis Dimitrios, Giamarelou Panagiota, Konidari Anastasia
From the B Paediatric Clinic Paidon Aglaia Kyriakou Children's Hospital.
JPGN Rep. 2020 Dec 17;2(1):e019. doi: 10.1097/PG9.0000000000000019. eCollection 2021 Feb.
Myofibroblastic tumor is a mesenchymal neoplasm composed of myofibroblastic spindle cells with inflammatory infiltrate and considered to be of low-malignant potential tumor. Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a variant of myofibroblastic tumor with malignant characteristics; it mainly consists of round-to-epithelioid cells with positive nuclear membrane/perinuclear immunostaining for anaplastic lymphoma kinase (ALK) receptor tyrosine kinase. A gastric EIMS case in a 7-year-old boy is discussed. Our patient presented with severe anemia and melena. Magnetic resonance imaging of the abdomen and pelvis revealed a solid tumor (2.7 × 1.9 × 2.6 cm) at the posterior stomach wall. Upper gastrointestinal endoscopy revealed an irregular, protruding, highly vascular, approximately 2 cm mass close to the gastrooesophageal junction. Endoscopic biopsies were taken for histology; tumor cells were epithelioid with eccentric nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. Immunohistochemistry showed positive staining for desmin, smooth muscle actin, epithelial membrane antigen, cluster of differentiation CD30, and strongly positive staining for ALK. Fluorescence in situ hybridization analysis confirmed the presence of ALK rearrangements. A full-thickness surgical excision of the tumor with clear margins was performed. No adjunct treatment was administered and our patient has remained in full remission at 12 months following the surgery. To the best of our knowledge, this is the first pediatric case of gastric EIMS. Raised awareness and prompt recognition of special histological and immunochemical characteristics of EIMS can lead to accurate diagnosis and targeted therapy.
肌成纤维细胞瘤是一种间叶性肿瘤，由具有炎症浸润的肌成纤维梭形细胞组成，被认为是低恶性潜能肿瘤。上皮样炎性肌成纤维细胞肉瘤（EIMS）是肌成纤维细胞瘤的一种具有恶性特征的变体；它主要由圆形至上皮样细胞组成，间变性淋巴瘤激酶（ALK）受体酪氨酸激酶的核膜/核周免疫染色呈阳性。本文讨论了一名7岁男孩的胃EIMS病例。我们的患者表现为严重贫血和黑便。腹部和骨盆的磁共振成像显示胃后壁有一个实性肿瘤（2.7×1.9×2.6cm）。上消化道内镜检查发现靠近胃食管交界处有一个不规则、突出、血管丰富、大小约2cm的肿块。取内镜活检进行组织学检查；肿瘤细胞为上皮样，核偏位，核仁突出，嗜酸性细胞质丰富。免疫组织化学显示结蛋白、平滑肌肌动蛋白、上皮膜抗原、分化簇CD30染色阳性，ALK染色强阳性。荧光原位杂交分析证实存在ALK重排。对肿瘤进行了切缘清晰的全层手术切除。未给予辅助治疗，我们的患者在手术后12个月仍处于完全缓解状态。据我们所知，这是首例小儿胃EIMS病例。提高对EIMS特殊组织学和免疫化学特征的认识并及时识别，可实现准确诊断和靶向治疗。
