A Skin Inflammatory Myofibroblastic Tumor Penetrates Through Skull To The Dura: A Case Report

Abstract

Abstract Introduction/Objective Inflammatory myofibroblastic tumor (IMT) is currently accepted to be a true neoplasm with a wide spectrum of biological behavior, varying from benign lesions to the rare tumors which are multifocal and prone to recurrence. IMT is characterized by a proliferation of myofibroblastic spindle cells with an inflammatory infiltrate. It was first described in the lung and later on reported in various sites such as stomach, intestine, spleen, bone. Here we report a rare IMT case in that the tumor penetrates through skull and extends to the dura. Methods/Case Report A 29-year-old female presented with a slowly progressive upper head scalp mass of one-year duration. Magnetic resonance imaging showed a soft tissue mass that extended through the skull and into the dura. Patient denies headache, syncopal episodes, neck pain, back pain, radicular symptoms, weakness, ataxia, nausea, vomiting, bladder or bowel incontinence, saddle anesthesia, or changes from baseline hearing, vision, or speech. Grossly, serial sectioning of the scalp skin specimen revealed a well-circumscribed mass lesion with white, firm, and homogeneous cut surface, with no hemorrhage or necrosis identified. The lesion measured 7.0 x 6.5 x 1.7 cm in greatest dimension. The lesion involved the deep margin and extended to the skull and dura. On histopathological examination, the lesion was composed of variable admixture of spindle cells with eosinophilic cytoplasm and inflammatory cells comprising of plasma cells and lymphocytes. The spindle cells were positive for smooth muscle actin, CD10 (partial), and negative for AE1/AE3, ALK–1, CD34, CD68, CD117, Desmin, Myogenin, p53, S-100, and SOX-10. The Ki-67 showed a spindle cell proliferation index at about 2%. The patient successfully went through surgery and was followed up without complications. Results (if a Case Study enter NA) NA Conclusion Our case showed a rare IMT case harboring histologically benign features like low cellularity, minimal nuclear atypia, and low proliferative index, but demonstrating locally very aggressive biological behaviors. Complete surgical resection and close follow up are suggested to avoid recurrence. Further studies are needed in this field to design in-depth investigation for accurate diagnosis and better clinical outcomes.