XXXX arising in uterine lipoleiomyoma: a report of 3 cases and review of the literature.

@entity1 @entity3519 @entity2283 @entity242 @entity39 @entity7465 @entity5 @entity4483 @entity1822 @entity361 @entity1821
BACKGROUND: Primary @entity242 of the uterus are uncommon, @entity1822 being the most frequent. Most uterine @entity242 arise de novo, with malignant transformation of a benign @entity361 being a very rare event, and is reported only in leiomyomata. DESIGN: The clinicopathologic features of 3 uterine @entity1821 arising in association with a lipoleiomyoma were studied. Immunohistochemistry for @entity2283 , h-caldesmon, @entity4483 , and @entity7465 , and fluorescence in situ hybridization for the t(12;16) (q13;p11) were performed in all cases. RESULT: @entity1 ranged in age from 49 to 70 (mean, 59) years. The @entity5 were centered in the myometrium, ranged in size from 10 to 18.5 cm, and showed a gelatinous cut surface with foci of @entity39 . On microscopic examination, the @entity5 had well-circumscribed pushing margins. One @entity5 was uniformly hypocellular with a prominent myxoid background, and a striking delicate vascular network. Another @entity5 showed alternating hypocellular (myxoid) and hypercellular areas, whereas the third @entity5 was uniformly hypercellular with a hyalinized background. In the myxoid areas, the cells were small and spindle with oval nuclei and inconspicuous nucleoli. In the hypercellular areas, the cells were pleomorphic with large, hyperchromatic nuclei. Mitotic activity ranged from <3 to 7/10 high-power fields. Lipoblasts were present in all @entity5 but were more common in the hypercellular areas. Two @entity5 merged imperceptibly with a lipoleiomyoma (1 typical and 1 with bizarre nuclei), whereas the third @entity5 showed an infarcted area composed of ghost mature adipocytes admixed with hyalinized smooth muscle most consistent with an infarcted lipoleiomyoma. @entity5 were classified as myxoid, mixed myxoid and pleomorphic, and @entity1821 , respectively. The benign and malignant adipose components were positive for @entity4483 , whereas the benign smooth muscle component stained for @entity2283 and h-caldesmon. @entity7465 immunostain was positive in the 2 cases with a @entity1821 component. Fluorescence in situ hybridization analysis was successfully completed in only 1 of 3 @entity5 (pure @entity1821 ), which failed to show the @entity3519 . The @entity1 are alive and well 1, 2, and 20 years after initial surgery with no adjuvant therapy. CONCLUSIONS: Primary @entity1821 of the uterus are extremely rare and are most likely to arise from malignant transformation of a lipoleiomyoma. These @entity5 should be added to the differential diagnosis of @entity5 , @entity361 , and malignant mixed @entity5 (if pleomorphic) of the uterus.
