A Rare Case of Incidentally Diagnosed Pulmonary Inflammatory Myofibroblastic Tumour with Dramatic Response to Crizotinib in a Postpartum Woman.

Introduction: Inflammatory myofibroblastic tumours are rare neoplasms which most commonly affect children and young adults. With an intermediate malignant potential, they are typically detected in the abdomen, lung, mediastinum, head and neck, gastrointestinal tract, and genitourinary tract. Case description: We describe the case of a 33-year-old postpartum woman incidentally diagnosed with a pulmonary inflammatory myofibroblastic tumour following complaints of poorly controlled hypertension a week after caesarean section. She was ALK-negative and received an ALK inhibitor with complete resolution of the lesion. A ROS1-TFG fusion confirmed the diagnosis of an inflammatory myofibroblastic tumour after CT-guided fine needle aspiration. Discussion: This case highlights an uncommon presentation posing a diagnostic and therapeutic challenge and the potential treatment option of crizotinib. LEARNING POINTS: Inflammatory myofibroblastic tumour (IMT) is a rarely reported neoplasm arising in the abdominal soft tissues, the lung, mediastinum, head, neck, gastrointestinal tract, and genitourinary tract, with intermediate malignant potential.IMT is definitively diagnosed only after histological examination following surgical biopsy, based on immunohistochemical markers and the molecular characteristics of the tumour, but small biopsies may have a role in a large lesion.IMT did not cause any complications during gestation.Therapeutic approaches include surgical resection and chemotherapy, including with crizotinib, an ALK tyrosine kinase inhibitor.

Mucinous cystic neoplasm of the pancreas with neuroendocrine cells and malignant stroma.

Mucinous cystic neoplasms (MCN) with malignant sarcomatous stroma are rare aggressive tumors and there are few recorded cases. We report a case of MCN that had adenocarcinoma in situ and invasive adenocarcinoma with foci of sarcomatous stroma in a 40-year-old woman. Clear transition from adenocarcinoma areas into sarcomatoid foci was noted. The stromal component showed immunoreactivity for CK7 and Cam 5.2 supporting epithelial origin of the sarcomatoid areas. Associated areas of cytologically benign MCN epithelium were present and were immunoreactive for positive staining with pan-cytokeratin (AE1/AE3), cytokeratin 7 (CK 7), cytokeratin 20 (CK 20), pan-cytokeratin (Cam 5.2), epithelial membrane antigen (EMA), muscle specific actin (MSA), and carcino-embryonic antigen (CEA). Interestingly, definite scattered pear-shaped neuroendocrine cells, as evidenced by strong immunoreactivity for chromogranin and synaptophysin, were identified in the cytologically benign MCN lining but not in the malignant epithelial component. We found that these tumor cells probably arise from a single precursor cell capable of divergent differentiation.