Clinicopathological Analysis and Treatment of Inflammatory Myofibroblastic Tumor in Adult patients: a Retrospective Study of 74 Cases

摘要: Objective: Inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal neoplasm with diverse behaviors occurring in soft tissues and visceral organs. The clinical and pathological features of IMT in adult patients are not well understood. This study highlights the importance of comprehensive diagnostics, including histopathology, immunohistochemistry, and genetic testing, in managing IMTs. High ALK positivity in lung IMTs suggests targeted therapies’ benefit. ALK inhibitors should be considered for ALK-positive tumors. Regular follow-up is crucial due to relapse risk. Methods: We conducted a retrospective analysis of 74 patients diagnosed with IMTs at Peking Union Medical College Hospital between 2010 and 2023. Clinicopathological data, treatments, and outcomes were collected and analyzed. Results: Among the 74 patients (34 females, 40 males) at an average age of 50, the majority were asymptomatic. The most common tumor locations were the head and neck (24.1%), followed by lung (21.6%). Anaplastic lymphoma kinase (ALK) positivity was identified in 31% of cases, with the highest prevalence in lung IMTs (45.5%). Most patients underwent surgical resection, and some received postoperative treatments including radiotherapy, chemotherapy, or ALK inhibitors. The 1-year, 3-year, 5-year, and 10-year OS rates were 78.4%, 70.9%, 69.2%, and 69.2%, respectively. Limitations: This is a single-center retrospective study, and the characteristics of these patients may not be representative of all adult IMT patients. While the sample size of drug-treated patients is relatively small and heterogeneous, making further systematic analysis difficult. The mechanism of resistance to ALK inhibitors has not been determined. Conclusions: IMTs exhibit significant clinical heterogeneity, with lung IMTs demonstrated the highest rate of ALK positivity. While surgical resection remains the primary treatment modality, the observed rates of relapse and mortality underscore the necessity for more effective therapeutic strategies. ALK inhibitor such as crizotinib should be consideration for ALK positive patients. A deeper understanding of the molecular characteristics of IMTs may help to enhance diagnostic accuracy and inform the development of improved treatment options.