How to differentiate abdominal wall leiomyomas from desmoid tumors?

Background: Desmoid tumor and leiomyoma are abdominal wall tumors with similar clinical, radiographic, and histological features. However, differentiation between these two diseases is important because each may be linked to different systemic diseases, and their managements are entirely different. We proposed that misdiagnosis is possible in some cases. Patients and Methods: Between 1983 and 2010, patients with a history of uterine surgeries and diagnosed with either abdominal wall desmoid tumors or leiomyomas were studied. All the images reviewed by an independent radiologist and surgical specimen were reexamined by immunohistochemistry (IHC) techniques as a standard method to confirm the diagnoses. Results: Fifteen female patients (desmoid tumors, n = 10; leiomyomas, n = 5) were included. The diagnosis of IHC revealed that two cases initially thought to be leiomyomas were desmoid tumors, whereas the remaining 13 cases maintained their initial diagnoses. The accuracy of hematoxylin and eosin staining was 86.7%. All tumors excised without complications, except for one desmoid tumor that recurred and underwent another excision. Conclusion: Preoperative magnetic resonance imaging (MRI) can be considered to differentiate the two diseases, as well as the elimination of other associated systemic diseases should be performed routinely. If MRI is inaccessible or unavailable, preoperative fine-needle biopsy is recommended. Optional IHC staining is required if the primary histological assessment is equivocal or inconclusive.