Bizarre Leiomyoma Research Articles

Hemoperitoneum Secondary to Exogastric Leiomyoblastoma of the Stomach

1and Stout 2 to describe an uncommon type of gastric tumor derived from the smooth muscle tissue, with the same macroscopic features of leiomyoma, but with different histological features. The term does not equate malignancy, and all leiomyoblastomas should be referred to as either benign or malignant leiomyoblastomas. These tumors have been given several different names, such as bizarre leiomyoma, epithelioid leiomyoma, and epithelioid myosarcomas. Intraperitoneal bleeding is an extremely rare complication of smooth muscle tumors of the stomach. We describe a recent patient with such a presentation. Case Report

Expression of steroid receptors, Ki-67, and p53 in uterine leiomyosarcomas.

The expression of estrogen receptor (ER), progesterone receptor (PR), tumor suppressor oncogene p53, and Ki-67 was compared in uterine smooth muscle tumors, including leiomyosarcoma (LMS), tumor of uncertain malignant potential (UMP), cellular leiomyoma (CL), bizarre leiomyoma (BL), and usual leiomyoma (UL). ER and PR were expressed in all ULs. PR was expressed in UL irrespective of the phase of the menstrual cycle; this staining was also observed in CL, UMP, and BL, although BL showed variable staining for ER. Compared to these tumors, the expression of both ER and PR was markedly reduced in LMS. The results of ER and PR transcripts by reverse transcription-polymerase chain reaction were compatible with those of immunohistochemistry. The number of Ki-67 positive cells in LMS was significantly higher than in UMP, BL, CL, and UL. p53 immunoreactivity was seen in 10 of 14 LMSs, and missense mutation in the p53 gene was found in 4 of 10 LMSs. These results suggest that abnormal expression of ovarian steroid receptors, p53, and Ki-67 is frequently associated with LMS of the uterus.

Mast cells in smooth muscle tumors of the uterus.

Mast cells (MCs) have been reported in the myometrium and uterine smooth muscle tumors. We examined the number of MCs in various uterine smooth muscle tumors (including leiomyosarcomas) and assessed whether this feature might be of value in their pathologic diagnosis. The number of MCs in 95 uterine smooth muscle tumors, including 55 ordinary leiomyomas, 17 cellular leiomyomas, 8 bizarre leiomyomas, and 15 leiomyosarcomas, was counted using toluidine blue and immunohistochemical staining. The number of MCs that stained for tryptase was lowest in leiomyosarcoma and next lowest in ordinary leiomyoma; the number in each of these two groups was significantly lower than in the myometrium (p < 0.001). In cellular and bizarre leiomyomas, the number of MCs was significantly higher than in ordinary leiomyoma (p < 0.001 and p < 0.001, respectively) and leiomyosarcoma (p < 0.001 and p < 0.005, respectively). Statistical analysis revealed that counting the number of MCs and using a cut-off value of 16 MCs per high-power-field is useful for the differential diagnosis of leiomyosarcomas from cellular leiomyoma and bizarre leiomyoma, yielding 100% sensitivity and 96% specificity. The number of MCs was significantly lower in leiomyosarcomas at TNM stages III and IV than in those at stages I and II (p < 0.05), but there was no significant correlation between the number of MCs and patient survival. These results suggest that the number of MCs might be useful as part of a multivariate approach to the differential diagnosis of leiomyosarcoma from bizarre or cellular leiomyoma.

Bizarre leiomyomas of the uterus: a comprehensive pathologic study of 24 cases with long-term follow-up.

A series of 24 bizarre (symplastic, pleomorphic) leiomyomas was analyzed to determine their spectrum of gross and microscopic features and to establish their clinical behavior by obtaining long-term follow-up. Patients' ages ranged from 25 to 51 years (mean 40.7). Maximum dimension of the tumors was about 1-14 cm (mean 4.2), with 83% measuring <5.5 cm and 8% > or = 10 cm. Grossly, the tumors generally resembled ordinary leiomyomas; one third had yellow or tan areas, two had hemorrhages, and a few had focal softening, cavitation or myxoid change. When evaluable (50%), the tumor border was generally circumscribed. Cellularity was 1+ in 21%, 2+ in 58%, and 3+ in 21%. Two tumors were predominantly of epithelioid cell type. Bizarre giant cells were unifocal in 12.5%, multifocal in 37.5%, and diffusely distributed in 50%. More than one third of the tumor contained giant cells in 67%. Degenerative changes occurred in 38%, usually hydropic change. One had infarct-type necrosis. None had tumor cell necrosis. Fibrinoid change of blood vessels occurred in 21%, usually accompanied by chronic inflammation. Mitosis counts ranged from zero to 2.8 mitotic figures (MFs)/10 high-power fields (HPFs) (mean 0.8) by the average count method. By the highest count method, the range was 0-7 MFs/10 HPFs (mean 1.6), with 13% having none and 29% having > or = 2 MFs/10 HPFs. Some pyknotic and karyorrhectic nuclei resembled abnormal MFs. Treatment was hysterectomy in 20 and myomectomy in six (including two with subsequent hysterectomy). Complete follow-up was available in 100%, ranging from 1 to 18.9 years (mean 11.2). Postoperative intervals were > or = 10 years in 58% and > or = 5 years in 83% of cases. All patients were alive and well. Although three patients subsequently developed unrelated second primary malignant neoplasms, none developed recurrence or metastasis of bizarre leiomyoma. Bizarre leiomyomas have a wider range of morphologic changes and mitotic activity than previously documented. This study firmly establishes the benign behavior of bizarre leiomyomas, even for those tumors with high cellularity, numerous widely distributed bizarre cells, and mitosis counts in the 2-7 MFs/10 HPFs range by the highest count method.

Epithelioid smooth-muscle tumors of the uterus: a clinicopathologic study of 18 patients.

Epithelioid smooth-muscle tumors of the uterus are uncommon neoplasms for which prognostic factors have not been well established. A retrospective follow-up study of 18 uterine epithelioid smooth-muscle tumors was performed. Patients ranged in age from 27 to 83 years (mean, 45 years) and were separated into three groups based on the nuclear grade of the epithelioid tumor cells. Two tumors had grade 1 nuclei; both were examples of intravenous leiomyomatosis. They had highest mitosis counts of 1 and 3 mitotic figures (MF)/10 high-power fields (HPF), no tumor cell necrosis was found, and both patients were alive with no evidence of disease at 64 and 5 months' follow-up. Ten tumors had grade 2 nuclei. All had highest mitosis counts of 0 to 3 MF/10 HPF, except one (5 MF/10 HPF). Tumor cell necrosis was absent in nine and only one had an infiltrative border. Tumor size ranged from 1.5 to 14 cm. Two tumors contained pleomorphic ("symplastic") multinucleated giant cells similar to those seen in bizarre leiomyomas. All nine patients with follow-up were alive with no evidence of disease 5 to 203 months postoperatively (median, 74 months). One patient had also received adjuvant radiation therapy. Six tumors had grade 3 nuclei. Highest mitosis counts of 4 to 9 MF/10 HPF were found in five; one had 1 MF/10 HPF. Maximum tumor size ranged from 4.5 to 13 cm. Two had tumor cell necrosis, and two had an infiltrative border. Two of these patients died of tumor 11 and 132 months postoperatively. The former had widespread metastases at initial surgery (stage IVb); the latter patient (stage I) developed the first of seven tumor recurrences 3 years postoperatively. Both patients had also received adjuvant chemotherapy. Of the remaining four patients, two were alive with no evidence of disease at 48 and 83 months, one was alive (tumor status unknown) at 28 months, and one was lost to follow-up. Based on our findings and those in the literature, we conclude that uterine smooth-muscle tumors with a predominance of epithelioid cells are extremely uncommon and metastasize infrequently. No single histologic feature is predictive of metastatic potential. Clinically malignant tumors (i.e., epithelioid leiomyosarcomas) typically have the combination of significant nuclear atypia (either grade 2 or grade 3 nuclei) and some mitotic activity (usually at least 3 to 4 MF/10 HPF); most also have tumor cell necrosis.

Prediction of histopathologic features and proliferative activity of uterine leiomyoma by magnetic resonance imaging prior to GnRH analogue therapy: correlation between T2-weighted images and effect of GnRH analogue.

To predict the histological features and proliferative activity of leiomyomas and to evaluate the effect of GnRH analogues (GnRHa) by MR images, the correlation between MR images and histopathologic findings was studied on 137 leiomyomatous nodules from 79 patients. The correlation among cellularity, proliferative activity and MR images was studied on sections of 42 leiomyomatous, nodules stained with hematoxylin-eosin and immunohistochemistry for proliferating cell nuclear antigen. The utility of MR imaging in assessing response to therapy with a GnRHa (buserelin 900 micrograms/day, intranasal for 16 weeks) was studied on 62 leiomyomatous nodules from 29 patients. On T2-weighted MR images, we encountered five major images. According to the increase of signal intensity relative to that of the myometrium and/or the endometrium, the images were classified as Type 1, Type 2, Type 3, Type 4, and Type 5. Histopathologically, the majority of Type 1, Type 2 and Type 3 images had features of typical leiomyoma. Almost all cellular leiomyomas and bizarre leiomyomas had Type 4 images. Variable degenerative features were observed in the nodules with Type 5 images. According to the increase of signal intensity, leiomyomas had a tendency to show a high degree of both cellularity and proliferative activity. Moreover, the reduction rate of leiomyomatous nodules after GnRHa therapy correlated with the tumor signal intensity on T2-weighted images before therapy. The reduction rate was the lowest in Type 1 images (20.9%) and the highest in Type 4 images (50.7%). These results suggest that increased the signal intensity on T2-weighted MR images correlates with the cellularity and proliferative activity of leiomyomas, and with tumor response to GnRHa treatment. MR imaging enables quantitative monitoring of GnRHa therapy in patients with leiomyomatous nodules, and allows us to predict the histopathology, cellularity, proliferative activity, and shrinkage rate of nodules before GnRHa treatment.

Vulvar leiomyoma

Since symptoms of benign and malignant conditions in the vulvar area are frequently similar, early diagnosis and treatment are mandatory. A rare case of a bizarre leiomyoma in the area of Bartholin's gland, which presented as a Bartholin's abscess, is described and discussed.

Complex karyotypic anomalies in a bizarre leiomyoma of the uterus

Cytogenetic investigation of short-term cultures from a bizarre leiomyoma of the uterus, a tumor type not hitherto karyotypically characterized, revealed two abnormal clones with multiple complex rearrangements. Three-fourths of the aberrant cells were hypodiploid with the composite karyotype 38-44,XX,-6,-7,-10, -11,+20,-22,r(1),der(2)(:2p23----cen----2q13::1q21---- 1qter),der(2)t(2; 9)(p21;q13),t(5;?)(q35;?), t(5;?),(q35;?),+der(5)t(5;15)(q11;q15), der(8)t(8;11)(q24;q13),t(15;?)(p12;?),der(16)t(12;16)(q13;p13),+r,+mar. The remaining abnormal mitoses were hypotetraploid, with chromosome numbers ranging from 74 to 86. These massively rearranged cells showed the same markers that were found in the hypodiploid clone, but in duplicate, indicating that this clone had arisen through polyploidization of hypodiploid cells. Flow cytometry revealed a DNA index of 1.03.

Histogenesis of morphologic variations in tumors of the uterine wall

We investigated seven uterine wall lesions, selected because of the presence of unexpected patterns or components, to determine their relationship to normal uterine constituents. These lesions included a bizarre leiomyoma, a palisading leiomyoma which resembled a schwannoma, two myxomas, irradiated myometrium, a plexiform tumor, and a leiomyoma with tubular structures. All of these lesions except for the epithelial component of the plexiform tumor showed ultrastructural characteristics of smooth muscle, demonstrating a common origin from the myometrium. Two tumors, the plexiform tumor and the leiomyoma with tubules, had the pattern of epithelial structures suggesting origin from müllerian mesencyme: the plexiform tumor resembled incompletely differentiated endometrium and the tubular structures in the leiomyoma had features of mesothelium. We conclude that these varied and often confusing morphologic patterns reflect the capacity of uterine smooth muscle and stroma to undergo a wide spectrum of alterations including differentiation toward epithelial structures. Changes of this type occur in benign and malignant uterine stromal neoplasms and do not in themselves have prognostic significance.

Histogenesis of morphologic variations in tumors of the uterine wall

We investigated seven uterine wall lesions, selected because of the presence of unexpected patterns or components, to determine their relationship to normal uterine constituents. These lesions included a bizarre leiomyoma, a palisading leiomyoma which resembled a schwannoma, two myxomas, irradiated myometrium, a plexiform tumor, and a leiomyoma with tubular structures. All of these lesions except for the epithelial component of the plexiform tumor showed ultrastructural characteristics of smooth muscle, demonstrating a common origin from the myometrium. Two tumors, the plexiform tumor and the leiomyoma with tubules, had the pattern of epithelial structures suggesting origin from müllerian mesenchyme: the plexiform tumor resembled incompletely differentiated endometrium and the tubular structures in the leiomyoma had features of mesothelium. We conclude that these varied and often confusing morphologic patterns reflect the capacity of uterine smooth muscle and stroma to undergo a wide spectrum of alterations including differentiation toward epithelial structures. Changes of this type occur in benign and malignant uterine stromal neoplasms and do not in themselves have prognostic significance. Am J Surg Pathol 4: 59-74, 1980.

Vascular leiomyosarcoma.The malignant counterpart of vascular leiomyoma

The clinical and pathological findings of six cases of leiomyosarcoma arising from blood vessels of different caliber are described. The term vascular leiomyosarcoma, having both a topographic and morphologic significance, is proposed for these tumors. The histologic pattern is characterized by a proliferation of atypical smooth muscle cells with a large number of intermingled blood vessels. Mitoses were counted per 10 high power field (hpf) and tumors were divided in three groups I, 10 to 20 mitoses, group II, 20 to 35 mitoses, and group III, more than 35 mitoses per 10 hpf. The mitotic index seems to be the most important pathological feature on which a prognostic evaluation for vascular leiomyosarcoma can be based. Tumors in group I had neither local recurrences nor metastases; the one tumor in group II had one local recurrence, but the patient is free of disease 6 years after surgical treatment; the three tumors in group III developed distant metastases and constitutional symptoms. Vascular leiomyoma, bizarre leiomyoma, and hemangiopericytoma are included in the differential diagnosis of vascular leimyosarcoma. The possibility that vascular leiomyosarcoma arising from small vessels represents the malignant counterpart of vascular leiomyoma is proposed.

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 hpt 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 <0.01). Gross evidence of extrauterine extension was diagnostic of maHgnancy 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.

Leiomyosarcoma of the uterus

Histologic material from 153 cases of uterine tumors with prior diagnosis or suspicion of sarcoma was reviewed. On the basis of cellularity, pleomorphism, and mitotic counts, 81 smooth muscle tumors were divided into 32 leiomyosarcomas, 31 cellular leiomyomas, 17 bizarre leiomyomas, and one intravascular leiomyoma. Only one case among the 153 was lost to follow-up. The average yearly instance rate for leiomyosarcoma was 0.67 per 100,000 women 20 years old and older. The incidence was significantly higher in Negroes than in Caucasians. The 5-year survival rate was 20.7%; however, three of the six 5-year survivors subsequently died of disease, and one is living with disease. Mitotic counts accurately separate leiomyosarcoma from cellular leiomyoma. No patient with fewer than five mitoses per 10 high-power field died of disease. The average length of follow-up was 12 years. In spite of the alarming histologic and cytologic features of bizarre leiomyomas no patient died of disease. Follow-up averaged 11.2 years.

Bizarre leiomyoma of the stomach: Case report.

Bizarre leiomyoma of the stoirtach, which has become an accepted and well‐documented entity in the course of the past decade, has to date received mention in Australasian literature on an extremely scanty basis. A case is now reported in full in order to draw further attention to the condition, of which the characteristic features are discussed in some detail.

A comprative electron microscopic study of a leiomyosarcoma and bizarre leiomyoma (leiomyoblastoma) of the stomach.

Two grossly similar neoplasms of the stomach were studied with the light and electron microscope. They were diagnosed as well-differentiated leiomyosarcoma and leiomyoblastoma, respectively. The leiomyosarcoma cells contained scanty myofibrils as compared with normal smooth muscle but exhibited a striking number of mitochondria. The cells of the leiomyoblastoma exhibited more myofibrils, and its vacuolar nature was confirmed. Some of the vacuoles appeared to represent degeneration of mitochondria, others were clearly derived from rough-surfaced endoplasmic reticulum, and still others might well represent light cells among darker elements.