Clinical and Pathological Features of Lipoleiomyoma of the Uterine Corpus: A Review of 76 Cases

Abstract

Lipoleiomyoma is a rare and easily recognized benign variant of uterine leiomyoma, composed of an intimate admixture of mature smooth muscle cells and adipocytes, often with the former element predominant, most commonly found in the uterine corpus (1-4).In 1916, Lopstein first described a lipoleiomyoma, but this received little attention in the literature (5). Its lack of specific histological features led researchers to underestimate its occurrence rate. The largest reports in the literature belong to Wang et al. (1) with 50 cases and Aung et al. (2) with 17 cases. To this day, there is no uniform accepted classification and the histogenesis is not resolved. Willen and Pounder (5, 6) designated these tumors as "uterine fatty tumors" and subdivided them into "lipoma" and "mixed lipoma/leiomyoma" (lipoleiomyoma). Modern research rejects the view that these tumors are hamartomas, choristomas, fatty metamorphosis, or lipomatous degeneration. They probably represent tumor metaplasia within a leiomyoma. However, some studies show monoclonality (7), and lipoleiomyoma is now regarded as a distinctive true neoplasm (8). Therefore, its pathogenesis and clinical significance remain to be clarified. Regardless of its origin, lipoleiomyomas have been consistently considered benign.Our study aimed to investigate the clinical, pathological and immunohistochemical features of uterine lipoleiomyoma and to confirm the benign nature of these tumors. MATERIAL AND METHODSThis is a retrospective study of 70 patients who had undergone hysterectomy and myomectomy over a 13-year period Background: Uterine lipoleiomyoma is a rare and specific type of leiomyoma with a considerable amount of adipocytes. Aims: The aim of the study was to investigate the clinical, pathological and immunohistochemical features of lipoleiomyoma of the uterine corpus, and review its histogenesis and differential diagnosis from other neoplastic and non-neoplastic lesions in order to obtain a detailed profile of this somewhat uncommon lesion. Study Design: Descriptive study. Methods: This study is a retrospective analysis of 70 consecutive women with 76 lipoleiomyomas, who underwent surgery mainly for uterine leiomyoma and gynecological carcinomas between January 2000 and April 2013. Clinical and pathological information was obtained from medical records. Immunohistochemistry was applied in selected cases. Parametric methods were used to compare clinical and pathologic features. Results: The patients ranged in age from 34 to 77 years (mean 55.49 years). Lipoleiomyomas ranged from 0.5 to 55 cm in diameter (mean 5.50 cm). Typical macroscopic and microscopic features were noted.Sixty-nine (90.7%) tumors were in the uterine corpus and five (6.5%) were in the cervix. One broad ligament tumor and one retroperitoneal tumor were also studied. No tumors displayed cytologic atypia, mitosis, necrosis, calcification, or other degenerative changes. Immunohistochemically, the adipose tissue element was positive for vimentin, desmin, S100 protein, estrogen (ER), progesterone (...

Giant lipoleiomyoma-an intimidating entity: case report and literature review

“…We reviewed cases published in literature of giant lipoleiomyoma measuring >20cm (Table 1). 3,6,7 Lower abdominal pain was most common presenting complaint in these patients followed by abdominal distension. Pre-operative scans in the largest reported tumor were suggestive of a malignant mass lesion, as was also observed in the present case.…”

“…2 However, in the recent years, several papers have been published discussing origin and presentation of this unusual entity. 3,4 Nevertheless, only few reports describe giant lipoleiomyoma.…”

“…Few reports have attributed the pathogenesis to divergent differentiation of uterine smooth muscles towards adipocytes; a theory supported by expression of ER, PR and Ki-67 in fat cells of lipoleiomyoma. 3,8 Another theory of adipocyte metaplasia of uterine smooth muscles is favored by reactivity of adipocytes in between smooth muscle cells for vimentin and desmin. These tumors also show t (12;14), a feature observed in conventional leiomyomas.…”

“…Akubulut et al in their review of conventional leiomyomas, found 46.05% (35 out of 76 cases) of patients had minimal lipomatous change, concentrated in focal areas only. 3 The differential diagnoses of uterine tumours with adipose tissue and spindle cells include spindle cell lipoma, angiolipoma, fibrolipoma and myolipoma. A meticulous review of histomorphology can help in differentiating these lesions.…”

Lipoleiomyoma of the Uterine Cervix: A Case Report

“…Daha az sık-lıkta submukozal ve subserozal lokalizasyondadır. Serviks uteri yerleşimli lipoleiomyomlar az sayıda literatürde bildirilmiştir (1,(6)(7)(8) . Yetmiş altı ve elli olguluk iki çalışmada uterin lipoleiomyomlar arasında serviks uteri lipoleiomyom oranı sırasıyla %6,5-13 oranında saptanmıştır (1,8) .…”