Simultaneous multiple primary cancers with concomitant inflammatory myofibroblastic tumor: a case report.

Multiple primary cancers are of rare occurrence. Most multiple primary cancers are metachronous multiple primary cancers, while simultaneous multiple primary cancers are rare. Inflammatory myofibroblastic tumors are rare. Inflammatory myofibroblastic tumor occurs most frequently in children and young adults. Herein, we report a rare case of simultaneous multiple primary cancers and inflammatory myofibroblastic tumor. A 44-year-old woman was admitted for a breast mass evaluation. The patient was positive for antinuclear, anti-mitochondrial, and anti-RO52 antibodies. Breast magnetic resonance imaging revealed a right breast mass. After neoadjuvant chemotherapy, modified radical mastectomy was performed. Postoperative histopathology revealed an invasive ductal carcinoma. Two months later, computed tomography revealed a nodule in the right upper lobe and ground-glass opacity in the lower lobe of the lungs. Lobectomy and lobe biopsy were performed. Postoperative histopathology revealed that the mass in the right upper lobe was an inflammatory myofibroblastic tumor and the right lower lobe lesion was an invasive adenocarcinoma. Immunohistochemistry of the inflammatory myofibroblastic tumor revealed negativity for anaplastic lymphoma kinase. At the 4-month follow-up, the patient showed good recovery. The etiology of multiple primary cancers and inflammatory myofibroblastic tumors is still unknown; in this case, we believe that autoimmune factors are the main cause of multiple primary cancers with concomitant inflammatory myofibroblastic tumor. Tissue biopsy is needed to ensure correct diagnosis of multiple primary cancers and inflammatory myofibroblastic tumor. Surgery-based comprehensive therapy is recommended. The prognosis is favorable and regular follow-up is necessary.