Uterine bizarre epithelioid lipoleiomyoma with a myxoid stroma

The first case of uterine bizarre epithelioid lipoleiomyoma with a myxoid component occurring in an 86-year-old woman is described. An intramural 22 cm mass in the anterior wall of the uterine body had a lipoma-like appearance with strands of fibrous tissue. Histologically, the tumor consisted of adipocytes which varied in size and shape, and epithelioid smooth muscle cells with nuclear atypia within a myxoid stroma. No mitotic features were noted despite an extensive search. The patient was well without disease 24 months after hysterectomy. Patients with this type of tumor need close and long-term follow-up because of the paucity of clinical information.     

Malignant rhabdoid tumor of the uterus

Rhabdoid tumors are highly malignant neoplasms resembling rhabdomyosarcomas, which most commonly occur in the kidney in young children. Several cases of extrarenal malignant rhabdoid tumors have been described, many in adolescents and young adults. We describe a 46-year-old woman with a primary uterine tumor that has the histologic, immunohistochemical, and ultrastructural characteristics of a malignant rhabdoid tumor. To our knowledge, this is the first report of a rhabdoid tumor in this site. Furthermore, this woman's age expands the range for which pathologists and clinicians should consider this diagnosis, even in extrarenal sites.     

Perivascular epithelioid cell tumor of the uterus: report of four cases.

Uterine perivascular epithelioid cell tumor (PEComa) is very rare, and there have been only 27 reported cases. The differentiation of the tumor has been enigmatic, and the biologic behavior remains unclear. This study describes the clinical, histologic, and immunohistochemical features of four cases of uterine PEComa. The patients were 30, 32, 36, and 40 years old, and none of them had tuberous sclerosis complex. The size of the tumors ranged from 1 to 30 cm in diameter, and 3 of the 4 tumors were confined in the uterus. One tumor involved the left ovary and omentum. Microscopically, the tumors were characterized by an epithelioid arrangement of tumor cells, which had abundant clear to eosinophilic pale granular cytoplasm, and one tumor had moderately atypical nuclei. Coagulative necrosis was found in two cases. The mitotic figures ranged from 0 to 11 per 10 high power fields. Immunohistochemically, the tumors were positive for vimentin (4/4), HMB45 (4/4), h-caldesmon (4/4), alpha-smooth muscle actin (3/4), muscle actin (2/4), and desmin (3/4). They were uniformly negative for Melan A, CD10, and S-100 protein. Ultrastructural examinations were performed on one case and revealed no melanosomes, premelanosomes, or evidence of smooth muscle differentiation. One patient died of intestinal metastases 17 months after surgery. The other patients have been well with no evidence of disease 8, 12, and 36 months after surgery. Uterine PEComa should be regarded as tumors with an uncertain malignant potential until long-term outcome data for a larger number of patients become available.     

Morphologic features of prognostic significance in uterine smooth muscle tumors: a review of eighty-four cases.

Independent microscopic review of the most cellular and pleomorphic areas of 84 smooth muscle tumors of the uterus by two pathologists yielded 23 leiomyosarcomas, 43 cellular leiomyomas, 16 bizarre leiomyomas, and two intravenous leiomyomas. Greater than 5 mitotic figures/10 high-power fields (hpf) correlated with malignant clinical behavior, but this occurred in only 75% of the leiomyosarcomas. Five cases with fewer than 5 mitoses/10 hpf pursued a malignant course. The mean age of the patients with malignant tumors (52.5 years) was similar to the mean age of those with bizarre leiomyomas (48.0 years) but those patients with cellular leiomyomas were significantly younger (42.0 years; p less than 0.01). Gross evidence of extrauterine extension was diagnostic of malignancy as was vascular invasion by anaplastic tumor. Fifteen of the 19 patients with leiomyosarcoma died of disease at an average of 28 months postoperatively. Inadequate sampling and interobserver variation are discussed.     

Epithelioid endometrial and endometrioid stromal tumors: a report of four cases emphasizing their distinction from epithelioid smooth muscle tumors and other oxyphilic uterine and extrauterine tumors.

Three endometrial and one extrauterine endometrioid stromal tumors (three sarcomas and one stromal nodule) with a prominent component of epithelioid cells with abundant eosinophilic cytoplasm are described. The patients were 39, 48, 56 and 86 years of age. The endometrial sarcomas were described grossly as an ill-defined tan nodule and "ragged and papillary," respectively, and had the typical infiltrative pattern of low-grade endometrial stromal sarcoma. The stromal nodule was a 13-cm, well circumscribed, yellow, fleshy mass. The extrauterine tumor was probably primary in the sigmoid colon. Oval to polygonal epithelioid cells with abundant eosinophilic cytoplasm accounted for 50% to 90% of the tumor cells. The cytoplasm was granular in one case. None of the tumors contained cells with a rhabdoid appearance. Nuclear and other features did not differ from those of usual endometrial-endometrioid stromal tumors except in one case in which there was greater nuclear pleomorphism. There was strong diffuse cytoplasmic immunoreactivity of all four tumors for vimentin and for CD10 in three of three tumors tested, as well as extensive and moderate reactivity for NK1/C3 and focal weak reactivity for CD68 in two of three tumors tested. Muscle actin positivity was very focal to extensive and weak to strong in all three tumors tested, mainly in the epithelioid areas; alpha-smooth muscle actin was focally to extensively positive in the epithelioid areas of two of three tumors tested; and focal strong desmin positivity (interpreted as indicating smooth muscle metaplasia) was found in the epithelioid areas of one of four tumors. A vaginal recurrence in one case had similar cytologic features to the primary tumor but when examined initially in the absence of adequate history posed diagnostic difficulty, as did evaluation of the uterine tumor in two other cases and the extrauterine tumor in the final case. The differential in these cases is primarily with an epithelioid smooth muscle tumor when they are uterine primaries. The typical infiltration facilitates this distinction in the cases of endometrial stromal sarcomas, but this feature is usually only evident in hysterectomy specimens. In limited samples such as biopsy or curettage specimens, and in some cases of recurrent tumor, awareness that endometrial-endometrioid stromal tumors can have epithelioid cells is crucial in the formulation of the differential diagnosis. Diverse oxyphilic tumors, including deciduoid malignant mesothelioma, can potentially be in the differential diagnosis with extrauterine (endometrioid) stromal sarcomas with epithelioid cells. Immunohistochemical evaluation may potentially provide major aid in diagnosis.     

Epithelioid vascular leiomyoma of the uterus mimicking glomangiomyoma

Case report: An unusual case of epithelioid vascular leiomyoma mimicking glomangiomyoma arising in the uterine corpus of a 55-year-old Japanese woman is presented. The surgically resected uterine mass, measuring 4.0 × 3.5 cm², demonstrated a dark red well-circumscribed tumor. Histologically, the rounded epithelioid cells around the dilated vessels showed gradual transition to spindled smooth muscle cells. Immunohistochemistry was positive for smooth muscle actin, but negative for collagen IV. Conclusion: The experience in this case emphasizes that glomangiomyoma-like feature is interesting and might indeed be a new histological variant of uterine leiomyomas.     

Differential expression of P16 and P21 in benign and malignant uterine smooth muscle tumors

Purpose  

The diagnosis of benign and malignant uterine smooth muscle tumors depends on morphologic criteria such as nuclear atypia, coagulative tumor cell necrosis and mitotic activity. Most of these tumors are readily classifiable into benign or malignant categories using these criteria. However, the distinction between leiomyomas and leiomyosarcomas may at times be problematic. Hence, it would be useful to have additional markers which could help to distinguish these tumors. The aim of the study was to evaluate p16 and p21 expressions in uterine smooth muscle tumors and determine whether p16 and p21 have a potential value in the differential diagnosis of problematic cases. In addition, we evaluated whether the differential expression of p16 and p21 in uterine leiomyosarcomas correlated with tumor recurrence and patient survival.     

Malignant mixed Müllerian tumor with rhabdoid features: a report of two cases and a review of the literature

Rhabdoid tumors were originally described as a type of pediatric renal neoplasm that contains cells resembling rhabdomyoblasts but lacking muscle differentiation. Extrarenal rhabdoid tumors have since been reported in multiple anatomic sites in the pediatric and adult population. These tumors are characterized by an aggressive clinical course, resistance to treatment, and a rapidly fatal outcome. Eight cases of uterine neoplasms with rhabdoid differentiation have been previously reported. In the three cases where clinical follow-up was available, the patients died of disease within 3 to 17 months after the diagnosis was established. We report two cases of uterine malignant mixed Müllerian tumor (carcinosarcoma) with rhabdoid differentiation. The findings and clinical outcome confirm the aggressive nature of uterine tumors with rhabdoid differentiation. One of the patients died of disease 3 months after initial operative treatment while the other patient's tumor recurred in 1 month and she died within 10 weeks. The poor prognosis of these neoplasms makes their histopathologic recognition important.     

Epithelioid angiomyolipoma of the ovary: a case report and literature review.

Angiomyolipoma (AML) is a benign mesenchymal neoplasm that mainly occurs in the kidney either sporadically or in patients with tuberous sclerosis complex (TSC). Extrarenal AML is uncommon. We describe a 39-year-old female with a history of TSC and bilateral multicentric renal AML who presented with a persistent cystic ovarian mass that fluctuated in size during 2 years of ultrasonographic observation before its removal by salpingo-oophorectomy. The 4.5-cm mass was solid and cystic and tan-yellow. Microscopic examination showed an admixture of epithelioid cells, smooth muscle bundles, large thick-walled blood vessels, and mature adipose tissue. The epithelioid cells had abundant eosinophilic cytoplasm and many had bizarre atypical nuclei including multinucleated forms. Mitoses were rare. Typical smooth muscle cells and the epithelioid cells were strongly immunoreactive for HMB-45. To our knowledge, this represents the first report of an AML arising in the ovary. The differential with other oxyphilic tumors of the ovary is discussed.     

Report of an unusual problematic uterine smooth muscle neoplasm, emphasizing the prognostic importance of coagulative tumor cell necrosis

Follow-up data of the clinical behavior of uterine smooth muscle tumors with low malignant potential are scarce. We present a woman suffering from a uterine smooth muscle cell tumor with increased cellularity, absence of significant atypia, and two to three mitotic figures per 10 HPFs but with minimal focal coagulative tumor cell necrosis (CTCN). These microscopic features are currently accepted to label the lesion as a "smooth muscle neoplasm of low malignant potential, limited experience." After a disease-free survival of 4 years, two retroperitoneal tumors around the iliac vessels were extirpated. Both tumors consisted of smooth muscle cells with mild to moderate atypia and a mitotic index of 5-10 per 10 HPFs but with multifocal and extensive CTCN. These microscopic features were sufficient to establish the diagnosis of leiomyosarcoma. This case adds to the limited experience of the clinical behavior of problematic uterine smooth muscle cell neoplasms and underscores the prognostic importance of CTCN.     

Ultrastructural study of minute uterine leiomyomas

Minute uterine leiomyomas, less than 3 mm in diameter, were studied by electron microscopy. In five of 15 cases, morphologically different types of smooth muscle cell were identified. In the central region of leiomyomas, most myoma cells were characterized by filaments sporadically located in the cytoplasm and well-developed organelles. These cells were interpreted as immature smooth muscle cells. In the outer layer of nodules, the cells were a more mature form of smooth muscle cell and resembled normal myometrial cells. The differences suggest that differentiation of the smooth muscle cells occurs early in the growth of uterine leiomyoma.     

Gastric Stromal Tumor with Peritoneal Nodules in Pregnancy: Tumor Spread or Rare Variant of Diffuse Leiomyomatosis

Gastric tumors discovered during pregnancy are rare. A cystic gastric stromal tumor with adjacent peritoneal nodules and associated with ascites was encountered in a 32-year-old pregnant patient. On initial clinical evaluation the mass was thought to originate from the uterine adnexa. The tumor itself was composed of uniform spindle cells with minimal mitotic activity. Immunohistochemical and ultrastructural studies were consistent with a gastrointestinal stromal tumor (GIST). Small nodules on the gastric serosa and adjacent omentum resembled those of leiomyomatosis peritonealis disseminata but were confined to the upper abdomen and on further study lacked evidence of smooth muscle differentiation. Although many of these nodules were not resected, a CT scans 3 and 9 months later failed to detect them. This case of GIST in pregnancy is apparently unique and distinct from leiomyomatosis peritonealis disseminata and rare forms of intestinal leiomyomatosis.     

Uterine adenomyomas excluding atypical polypoid adenomyomas and adenomyomas of endocervical type: a clinicopathologic study of 30 cases of an underemphasized lesion that may cause diagnostic problems with brief consideration of adenomyomas of other female genital tract sites.

We report 30 uterine tumors composed of an admixture of endometrioid glands, endometrioid stroma, and smooth muscle that lacked the characteristic features of atypical polypoid adenomyoma. The patients ranged from 26 to 64 (median 47) years of age. The usual presenting symptom was abnormal vaginal bleeding, which was "massive" in two patients. Six patients were treated by polypectomy only, with hysterectomy performed in the remainder. Twenty-seven adenomyomas were in the corpus (22 submucosal, two mural, and three subserosal) and three in the cervix. The subserosal and submucosal examples were polypoid. The tumors were 0.3 to 17 cm in greatest dimension, and firm with cystic areas often present on sectioning. Focal hemorrhage was described in five cases. On microscopic examination, the tumors were composed of glands and cysts lined by endometrial-type epithelium separated by endometrial stroma and smooth muscle, with smooth muscle predominating. Minor foci of tubal-type epithelium (14 cases), mucinous endocervical-type epithelium (2 cases), and squamous epithelium (1 case) were present. The smooth muscle component was cellular in three cases and contained occasional bizarre nuclei in three cases. The epithelial cells were uniformly bland. No mitotic activity was observed in the epithelial or mesenchymal elements in 20 cases. In the remainder, up to 5 mitotic figures/10 high-power fields were observed in the epithelium (3 cases), the stroma and smooth muscle (3 cases), or both compartments (4 cases). Follow-up in 14 cases revealed no recurrence or extrauterine spread in any case. A diagnosis of adenocarcinoma or adenosarcoma was entertained by the submitting pathologist in five of 14 consultation cases. Adenomyomas are unusual benign uterine tumors that can be misdiagnosed, in part, because the lesion has not often received attention in the literature. The most realistic considerations in the differential diagnosis are atypical polypoid adenomyoma and adenosarcoma. The former, by definition, has epithelial atypia and the latter a malignant (usually low grade) stromal component with typically absent or inconspicuous smooth muscle. Distinction of adenomyoma from adenosarcoma may have significant therapeutic implications, particularly in young women.     

Expression of chemokines CCL5 and CCL11 by smooth muscle tumor cells of the uterus and its possible role in the recruitment of mast cells

OBJECTIVE: Smooth muscle tumors of uterus have been reported to contain considerable number of mast cells, especially cellular leiomyoma. However, to our knowledge the mechanism by which mast cells increased in them is not known. The purpose of this study was to reveal the different mast cell subsets in smooth muscle tumors of uterus and to investigate the mechanism of local increase of mast cells. METHODS: Tissue sections from 85 uterine smooth muscle tumors were studied using immunohistochemical double labeling techniques, including 40 cases of ordinary leiomyomas, 30 cases of cellular leiomyomas and 15 cases of leiomyosarcomas. The sections were double immunostained for mast cell tryptase and chymase, mast cell tryptase and ki-67, mast cell tryptase and chemokines (i.e., CCL2, CCL5, CCL11, TGFbeta), as well as tryptase and CCR3. RESULTS: MC(TC)-type of mast cells was the predominant type in ordinary leiomyoma and cellular leiomyoma, whereas MC(T)-type was seldom found in them. There was no MC(C) in smooth muscle tumors. The total intratumoral number of mast cells in cellular leiomyoma group was significantly higher than that in both leiomyosarcoma and ordinary leiomyoma (P<0.01). Mast cells proliferation was rarely detected in smooth muscle tumors, as revealed by constant negative labeling of the proliferation marker Ki-67 in mast cells. Almost all mast cells (tryptase positive) in smooth muscle tumors were also CCL2, CCL5, CCL11 and TGFbeta positive. Expressions of CCL5 and CCL11 in tumor cells in cellular leiomyoma were all significantly higher than that in both ordinary leiomyoma and leiomyosarcoma (P<0.01). While the expression of TGFbeta in tumor cells in cellular leiomyoma was not significantly different from that in ordinary leiomyoma, expression of CCL2 was not observed in smooth muscle tumor cells. There were positive correlations between CCL5 and the number of mast cells (r(s)=0.801, P<0.01) and between CCL11 and the number of mast cells (r(s)=0.744, P<0.01) in smooth muscle tumors as well. The vast majority of the mast cells in cellular leiomyoma were CCR3 positive. CONCLUSIONS: Using the monoclonal anti-mast cell tryptase antibody could detect all mast cells in smooth muscle tumor. The increased intratumoral mast cell counts in cellular leiomyoma might be the result of mast cells recruitment from the peripheral blood rather than local mast cells proliferation. CCL5 and CCL11, which are expressed by smooth muscle tumor cells, are possibly responsible for the recruitment of mast cells in uterine cellular leiomyoma. Whether they combine to CCR3 expressed by mast cells need further study.     

Ki-67 expression in patients with uterine leiomyomas, uterine smooth muscle tumors of uncertain malignant potential (STUMP) and uterine leiomyosarcomas (LMS)

BACKGROUND: The aim of the current study was to evaluate the expression of Ki-67 in uterine smooth muscle tumors, comparing leiomyomas, uterine smooth muscle tumors of uncertain malignant potential (STUMP) and uterine leiomyosarcomas (LMS) and to prove the accuracy of a Ki-67 expression as a useful parameter in the diagnosis of LMS. METHODS: Ki-67 was assessed using immunohistochemistry from paraffin-embedded tissue in 20 patients with uterine LMS, 22 cases of STUMP and 25 cases of leiomyomas. RESULTS: Ki-67 was present in 10/20 (50%) LMS, in 0/22 (0%) STUMP and in 2/25 (8%) leiomyomas. Significant differences regarding the frequency of Ki-67 expression were observed between LMS and STUMP (p = 0.0001) as well as between LMS and leiomyomas (p = 0.002), but not between STUMP and leiomyomas (p = 0.491). Likewise, the staining intensity differed significantly between LMS and leiomyomas (p = 0.018) as well as between LMS and STUMP (p = 0.002), but not between STUMP and leiomyomas (p = 0.368). CONCLUSIONS: Our results demonstrate that the significantly elevated Ki-67 antigen expression in LMS, which correlates well with the rapid growth of these malignant tumors, may be a useful immunohistochemical parameter to distinguish between cases of malignant smooth muscle tumors and those of uncertain or borderline histology.     

Primary extrarenal rhabdoid tumor of the ovary. A case report

BACKGROUND: Malignant rhabdoid tumors are rare, aggressive neoplasms that consist of both renal and extrarenal subtypes. Although extrarenal rhabdoid tumors have been documented at multiple extrarenal sites, to our knowledge no primary ovarian cases have been reported. CASE: An 18-year-old, Caucasian woman was diagnosed with a pure primary extrarenal rhabdoid tumor of the ovary following diagnostic laparoscopy for pelvic pain. The tumor exhibited rapid growth, failed to respond to chemotherapy and led rapidly to death. CONCLUSION: Although no other reports on primary ovarian extrarenal rhabdoid tumor have been published, the aggressive behavior of the tumor in this patient was similar to that seen in patients with metastatic disease.     

Positron emission tomography and leiomyomas: clinicopathologic analysis of 3 cases of PET scan-positive leiomyomas and literature review

INTRODUCTION: Studies have suggested that PET scans can differentiate between leiomyomas and leiomyosarcomas. Our experience, however, shows that PET scan-positive smooth muscle tumors are not necessarily malignant. CASE REPORTS: Three patients with cancer underwent PET imaging. In all three, the most worrisome finding was a PET scan-positive uterine tumor. After surgical extirpation, all three uterine tumors were found to be benign smooth muscle neoplasms. DISCUSSION: To explore the potential reason these tumors were positive on PET imaging, we performed a detailed histopathologic and immunohistochemical study of all specimens. Pathologic evaluation revealed a leiomyoma, a cellular leiomyoma, and a stromomyoma. There was no association between an increased Ki67 (proliferative) index and positivity on PET imaging. Increased vascularity, however, appeared to be a feature common to the leiomyomas that were PET-positive.     

Diagnostic criteria for uterine smooth muscle tumors: leiomyoma variants associated with malignant behavior

OBJECTIVE: To determine the prognostic accuracy of current diagnostic criteria for uterine smooth muscle tumors. STUDY DESIGN: Cases of uterine leiomyosarcoma (LMS) treated from 1976 to 1999 were analyzed retrospectively. Uterine LMS specimens were reevaluated using current criteria by a pathologist specializing in gynecologic diseases. Kaplan-Meier survival curves were evaluated. RESULTS: Specimens were available from 67 patients diagnosed with uterine LMS. On rereview, only 47 specimens were thought to represent uterine LMS. The 20 other patients were deemed to have leiomyomas or leiomyoma variants, including 13 cellular leiomyomas, 5 atypical leiomyomas and 2 leiomyomas. Median survival for patients with uterine LMS was 2.1 years. (Ninety-seven percent of disease-specific deaths occurred within 6 years after the diagnosis.) With leiomyoma variants, median survival was > 25 years. Among these 18 women were 3 disease-specific deaths (all > 6 years after diagnosis). CONCLUSION: Diagnostic criteria for uterine smooth muscle tumors require continued refinement. A small but significant number of patients diagnosed with leiomyoma variants will die of the disease. In contrast to the aggressive behavior of uterine LMS, disease-specific deaths attributed to leiomyoma variants occurred later. With this potential for delayed recurrence, these patients warrant close clinical surveillance.     

Recurrent benign metastasizing leiomyoma after hysterectomy and bilateral salpingo-oophorectomy

BACKGROUND: Benign uterine leiomyomas are sometimes found in association with benign smooth muscle tumors outside the confines of the uterus and are given the name benign metastasizing leiomyomas (BML). We present two patients who were on estrogen replacement therapy, in which BML recurred twice despite previous hysterectomy and bilateral salpingo-oophorectomy (TAH/BSO) requiring two additional laparotomies. PATIENTS: Our patients, presented with multiple abdominal masses 6 years after their initial surgery for benign leiomyoma. At exploratory laparotomy multiple benign leiomyomas were resected, and in one case a 2.2 cm leiomyoma was also resected from the left lower lobe of the lung. Both patients had a third laparotomy for another abdominal recurrence approximately 2 years later. RESULTS: Pathology revealed benign leiomyomas with no cytological atypia and a mitotic count of <5 per 10 high power fields (hpf). CONCLUSION: Benign metastasizing leiomyoma rarely follow TAH/BSO in patients with uterine myoma and estrogen replacement therapy may play a role in such occurrence. Despite surgery to remove these tumors, they can still recur; therefore, there is need for prolonged surveillance in such patients after resection.