Inflammatory Myofibroblastic Tumor: A Rare Presentation and an Effective Treatment with Crizotinib

Abstract

Inflammatory myofibroblastic tumor (IMT) is a rare entity of neoplastic origin. It usually occurs in children and adolescents and most commonly involves pulmonary and gastrointestinal sites. Here, the authors present two cases; one is the nine months old boy with a subcutaneous IMT in the left temporal region that was treated successfully with surgical resection. To the best of our knowledge, this is the first reported case of a subcutaneous IMT in this particular region. The second is an eight years old girl with an IMT of the right hemi-pelvis. The mass had complete surgical excision with clear margins and no residual disease. She was kept on regular follow-up with ultrasound abdomen. However, her disease relapsed with the appearance of lesions in right iliac fossa, right ovary, and liver. Biopsy of the relapsed abdominal mass confirmed ALK-positive IMT. She was treated with ALK inhibitor Crizotinib. She was monitored with regular blood complete picture, hepatic and renal function test, and ultrasound abdomen. Her lesions started regressing within one month, and she achieved complete remission after 6 months of treatment.

Figure 1

CT scan brain showing soft tissue mass in right temporal area under the skin not involving bone and brain.

Figure 2

Microscopic appearance of inflammatory myofibroblastic tumor. Spindle cells with inflammatory cells.

Figure 3

Immunohistochemical staining showing ALK Positivity.