Foci of decreased signal on T2-weighted MR images in leiomyosarcomas of soft tissue: correlation between MR and histological findings.
OBJECTIVE: Leiomyosarcomas are rare soft tissue sarcomas with varying MR signal characteristics and histologic pictures. The purpose of this study was to investigate the histological features of foci, which showed decreased signal on T2-weighted images in leiomyosarcomas of soft tissue. MATERIAL AND METHODS: We reviewed the MR images of six histologically proved cases of leiomyosarcomas of soft tissue and correlated the foci, which showed decreased signal on T2-weighted images with the histologic findings. RESULT: Microscopic examination revealed that these foci were composed of hyalinization of neoplastic tissue, internal septations, deposition of hemosiderin, or corresponded to metaplastic bone. CONCLUSION: The authors explain that the foci of decreased signal on T2-weighted MR images correspond to tissue components of the lesion, particularly fibrous tissue, hemosiderin and metaplastic bone. So, the suggestion is that leiomyosarcoma should be considered in the differential diagnosis of soft-tissue tumors that show foci of decreased signal on T2-weighted MR images.