PATHOLOGIC CONSIDERATIONS OF UTERINE SMOOTH MUSCLE TUMORS

Clinical features of uterine sarcomas presenting mainly with uterine masses: a retrospective study

BACKGROUND

Uterine sarcomas are uncommon mesenchymal tumors of the uterus. The clinical problem is that the features of uterine sarcomas can sometimes mimic uterine fibroids. This study aims to investigate the clinical characteristics of patients with uterine sarcomas who were preoperative presenting mainly with uterine masses.

METHODS

A retrospective analysis of patients who underwent gynecological surgery for uterine sarcomas at the Obstetrics & Gynecology Hospital of Fudan University, between January 2016 and December 2021.

RESULTS

Over the 5-year period, 277 patients were final diagnosed of uterine sarcomas. A total of 162 patients were preoperatively diagnosed as uterine fibroids for surgical treatment, the majority of whom were diagnosed of uterine leiomyosarcoma (uLMS) (49/162) and low-grade endometrial stromal sarcoma (LG-ESS) (100/162). Ninety people underwent total hysterectomy and bilateral salpingo-oophorectomy (TH + BSO), while 72 underwent myomectomy followed by supplemental TH + BSO. The group with direct hysterectomy had a higher average age than the group with prior myomectomy (47.20 ± 8.94 vs. 40.86 ± 5.88, p < 0.001). Among patients preoperatively diagnosed as uterine fibroids, patients with uLMS had a higher proportion of previous myomectomy (26.53% vs. 5.00%, p < 0.001), a larger uterine mass diameter on ultrasound (8.38 ± 3.39 cm vs. 6.41 ± 1.92 cm, p < 0.001), and richer hypervascularity (34.69% vs. 18%, p = 0.024) compared with LG-ESS.

CONCLUSIONS

Analysis of our data showed that a large proportion of uterine sarcomas, especially uLMS and LG-ESS, present mainly with uterine masses. Ultrasound features including a large uterine mass diameter and rich hypervascularity, and with a history of myomectomy may alert clinicians in suspicion of uLMS when compared with LG-ESS.

Torsion of a huge subserosal uterine leiomyoma: A challenging case of acute abdomen

Torsion of a uterine leiomyoma is an extremely rare, albeit life-threatening surgical emergency. A 28-year-old woman presented with acute abdominal pain. Imaging revealed a torsed subserosal uterine leiomyoma which was managed surgically and the diagnosis confirmed intraoperatively as well as on histopathology.

Contribution

While intraoperative findings remain the primary means of diagnosis, radiologists should be familiar with the potential imaging findings of leiomyoma torsion as timely intervention can greatly improve patient outcome.

MRI Evaluation of Uterine Masses for Risk of Leiomyosarcoma: A Consensus Statement

Laparoscopic myomectomy, a common gynecologic operation in premenopausal women, has become heavily regulated since 2014 following the dissemination of unsuspected uterine leiomyosarcoma (LMS) throughout the pelvis of a physician treated for symptomatic leiomyoma. Research since that time suggests a higher prevalence than previously suspected of uterine LMS in resected masses presumed to represent leiomyoma, as high as one in 770 women (0.13%). Though rare, the dissemination of an aggressive malignant neoplasm due to noncontained electromechanical morcellation in laparoscopic myomectomy is a devastating outcome. Gynecologic surgeons' desire for an evidence-based, noninvasive evaluation for LMS is driven by a clear need to avoid such harms while maintaining the availability of minimally invasive surgery for symptomatic leiomyoma. Laparoscopic gynecologists could rely upon the distinction of higher-risk uterine masses preoperatively to plan oncologic surgery (ie, potential hysterectomy) for patients with elevated risk for LMS and, conversely, to safely offer women with no or minimal indicators of elevated risk the fertility-preserving laparoscopic myomectomy. MRI evaluation for LMS may potentially serve this purpose in symptomatic women with leiomyomas. This evidence review and consensus statement defines imaging and disease-related terms to allow more uniform and reliable interpretation and identifies the highest priorities for future research on LMS evaluation.

A feasibility analysis of the ArcBlate MR-guided high-intensity focused ultrasound system for the ablation of uterine fibroids

Purpose

Uterine fibroids are benign gynecologic tumors and commonly occur in women by the age of 50. Women with symptomatic uterine fibroids generally receive surgical intervention, while they do not favor the invasive therapies. To evaluate the feasibility and safety of a novel magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) modality, ArcBlate, in the treatment of uterine fibroids.

Methods

Nine patients with uterine fibroids and one patient with adenomyosis were treated with ArcBlate MRgHIFU. Tumor size and quality of life were evaluated postoperatively at 1 and 3 months by magnetic resonance imaging (MRI) and the 36-Item Short Form Survey (SF-36), respectively.

Results

All patients completed the ArcBlate MRgHIFU procedure and there were no treatment-related adverse effects either during the procedure or during the 3 months of follow-up. Despite limiting the ablation volume to under 50% of the treated fibroid volume as a safety precaution, tumor volumes were markedly reduced in four patients by 15.78–58.87% at 3-month post-treatment. Moreover, SF-36 scale scores had improved at 3 months from baseline by 2–8 points in six patients, indicating relief of symptoms and improved quality of life.

Conclusion

This study evidence demonstrates the safety and feasibility of ArcBlate MRgHIFU and suggests its potential for treating uterine fibroids.

Predictors of adverse outcome in uterine smooth muscle tumours of uncertain malignant potential (STUMP): a clinicopathological analysis of 22 cases with a proposal for the inclusion of additional histological parameters

AIMS

The current World Health Organisation classification defines smooth muscle tumours of uncertain malignant potential (STUMPs) as neoplasms that cannot be diagnosed reliably as benign or malignant according to generally accepted criteria. This has led to the application of various sets of criteria; consequently, consistent and reliable outcome data are lacking. The aims of this study were: (i) to compare the frequency of adverse outcome in STUMP on the basis of enhanced criteria; and (ii) to perform failure analysis to identify feature(s) helpful in predicting outcome METHODS AND RESULTS: Cases of STUMP diagnosed between 1994 and 2009 were retrieved and follow-up data were collected. Morphological parameters were scored and correlated with outcome. Twenty-two subjects with a median follow-up of 74.5 months (range, 26-166 months) formed the study group. Their age ranged from 31.9 years to 51.8 years (median, 45.3 years). Sixteen subjects underwent hysterectomy and six underwent myomectomy. Adverse outcomes were noted in eight (36.4%) cases. In cases with adverse outcomes, notable features included moderate-severe nuclear atypia (seven), epithelioid features (one), infiltrative or irregular margins (five), atypical mitoses (two), and vascular intrusion (three) CONCLUSIONS: The frequency of adverse outcomes in our series (36.4%) was higher than that in previously published reports (7-26.7%), suggesting that the use of more stringent criteria can exclude some patients from further follow-up. Although 'significant' nuclear atypia was not discriminatory, its frequent association with adverse outcomes has pathobiological implications. The presence of necrosis was not particularly associated with adverse outcomes. Atypical mitoses, epithelioid differentiation, vascular involvement and infiltrative/irregular margins appear to herald adverse outcomes, and therefore merit inclusion in the diagnostic regimen.

Recurrent benign leiomyomas after total abdominal hysterectomy. Rich or poor estrogenic environment may lead to their recurrence?

INTRODUCTION

Benign metastasizing leiomyomas represent benign lesions consisted by leiomatosous tissue and could be observed in positions away from their usual localization, the human uterus. They commonly affect women that have undergone total hysterectomy. Approximately 100 similar cases have been reported in the literature, so the case we present is rare and reviewing the literature and needs to be reported.

PRESENTATION OF CASE

We report a case of a 55 year old Greek woman, gravida five and para three, who attended our unit 3 years ago complaining of occasionally lower abdominal pain and irritation the last months. Fourteen years ago she underwent abdominal hysterectomy and left salpingo-oophorectomy due to a 13 cm uterine leiomyoma. In the meantime she underwent two surgical procedures for recurrent benign leiomyomas.

DISCUSSION

When patient was admitted at this time, clinical examination revealed a palpable mass of 5 cm. The transvaginal ultrasonography revealed 3 masses in the lower pelvis of unknown origin. The patient underwent a new laparotomy revealing three masses of benign leiomyomas with low mitotic activity.

CONCLUSION

Our case supports the recurrent appearance of leiomyomas in pelvis after total abdominal hysterectomy and is one of few reports in literature where the tumors appear in the same patient both in estrogen rich and estrogen poor environment. Additionally, we show the importance of transvaginal ultrasonography and 3 dimensional power Doppler in the differential diagnosis of pelvic masses. Thus, transvaginal ultrasonography seems to be a pivotal tool for the diagnosis and follow up of these challenging lesions.

Ultrasound guided core needle biopsy prior to thermo ablative treatment of uterine tumors: first results

PURPOSE

This study aimed at evaluating the diagnostic yield for core needle biopsies of uterine fibroids before laparoscopic radiofrequency volumetric thermal ablation (RFVTA) with the aim of sonographic imaging. This study was in the context of a randomized, prospective, single-center, longitudinal comparative study in which RFVTA and laparoscopic myomectomy for symptomatic uterine fibroids were compared.

METHODS

All patients of the RFVTA-arm received a core needle biopsy under the guidance of an intraoperative laparoscopic ultrasound system. The Tissue samples were observed histologically.

RESULTS

24 patients were included and received in the median 3.17 biopsies (range 2-7). 45.8% of the fibroids were intramural. In 92% uterine leiomyoma was detected, in 4% a cell rich leiomyoma and in 4% a smooth muscle tumor with uncertain malignant potential (STUMP). There were no complications caused by core needle biopsy.

CONCLUSIONS

Ultrasound guided core needle biopsy can be used to receive a histological result before treating uterine fibroids with thermo surgical methods like RFVTA.

Benign metastasizing leiomyoma presenting as multiple cystic pulmonary nodules: a case report

BACKGROUND

Benign metastatic leiomyoma (BML) is an extremely rare disease. Although uterine leiomyomas are benign histologically, they can metastasize to distant sites. While the incidence is very low, the lung is the organ most frequently affected by BML. Pulmonary BML usually presents as numerous well-defined nodules of various sizes, while the cavitary or cystic features in the nodules are rarely observed on radiologic images.

CASE PRESENTATION

A 52-year-old woman complained of cough and dyspnea for one month. She had been previously diagnosed with uterine leiomyoma and had undergone total hysterectomy about 14 years prior. High-resolution computed tomography (CT) images showed that there were multiple cystic nodules of various sizes in both lungs. Pathologic examination revealed that the pulmonary nodule had complex branching glandular structures lined by a single layer of simple cuboidal to columnar epithelium that was surrounded by abundant spindle cells. Additional immunohistochemistry data suggested that pulmonary nodule diagnosis was BML-associated uterine leiomyoma.

CONCLUSION

In this report, we introduce an interesting case of pulmonary BML that presented as a combination of various kinds of nodules including simple round nodules, simple cysts, and cysts with a solid portion, which are very rare radiologic features of BML in lung. In addition, when the patient is a woman of reproductive age, physicians should meticulously review the gynecological history and suspect BML when there are various cystic pulmonary lesions.

Magnetic resonance imaging features of uterine sarcoma and mimickers

Uterine myometrial tumors are predominantly benign conditions that affect one-third of women and represent the main indication for hysterectomy. Preoperative imaging is of utmost importance for characterization and for precise mapping of myometrial tumors to best guide therapeutic strategy. New minimally invasive therapeutic strategies including morcellation, myolysis, uterine artery embolization and image-guided radiofrequency or focused ultrasound ablation have been developed for the treatment of uterine leiomyoma. However, preoperative differentiation between atypical leiomyomas and leiomyosarcomas is critical on imaging as uterine sarcoma requires a specific surgical technique to prevent dissemination. A single, rapidly growing uterine tumor, associated with endometrial thickening and ascites, in post-menopausal women is suspicious of uterine endometrial stromal sarcoma and carcinosarcoma. Suggestive magnetic resonance imaging features have been described, but overlap in imaging appearance between uterine leiomyosarcomas and cellular leiomyomas makes it challenging to ascertain the diagnosis. This review aims to illustrate the imaging features of uterine sarcomas and potential mimickers to make the reader more familiar with this serious condition which needs special consideration.

Leiomyoma originating from axilla: A rare case report and differential diagnosis

INTRODUCTION

Leiomyoma is a form of benign tumor originated in hypertrophy of the smooth muscles, which is most prevalent in the uterus and gastrointestinal tract. However, Leiomyoma originating from smooth muscle at the vessels lying on deep soft tissue is very rare.

CASE REPORT

Our case was a rare case of leiomyoma originating from the axillary region, which was initially diagnosed as a fibroadenoma on radiological examination. The mass was separated from surrounding tissues and totally resected. Pathologically, hematoxylin-eosin-stained biopsy tissue showed the typical findings of leiomyoma. Postoperative follow-up observation was done for 1 year, without any complications or recurrence.

CONCLUSION

Notably, a leiomyoma in the axillary region is difficult to differentiate from other benign or malignant tumors on preoperative radiological examinations such as ultrasonography or computed tomgraphy. Therefore, when an indefinite asymptomatic mass that is not lymphadenopathy or common benign tumor is identified in the axillary region, leiomyoma can be considered as one of the differential diagnoses.

Atypical uterine leiomyoma: a case report and review of the literature

Background

Atypical uterine leiomyomas show benign behavior. However, the distinction between leiomyomas and leiomyosarcomas may at times be problematic. We report a rare case of atypical uterine leiomyoma. We try to investigate potential immunohistochemical parameters that could be essential to distinguish cases of malignant smooth muscle tumors and those of uncertain or borderline histology.

Case presentation

A 56-year-old white ethnic Albanian woman from Kosovo presented with uterine bleeding because of uterine multiple leiomyomas. A hysterectomy with unilateral adnexectomy was performed. Her hysterectomy specimen contained multiple leiomyomas in submucosal, intramural and subserosal locations. The leiomyomas were well demarcated, firm and white with a whorled cut surface and one had foci of hemorrhage. Histology of most of the leiomyomas showed a whorled (fascicular) pattern of smooth muscle bundles separated by well-vascularized connective tissue. Smooth muscle cells were elongated with eosinophilic or occasional fibrillar cytoplasm and distinct cell membranes. Some of them developed areas of degeneration including hyaline change, with less than five mitotic figures per ten high power fields in most mitotically active areas, and no significant atypia. One leiomyoma was characterized by moderately to severely pleomorphic atypical tumor cells with low mitotic counts and no coagulative tumor cell necrosis. Immunohistochemistry showed strong immunoreactivity for vimentin, smooth muscle actin and desmin, while cyclin-dependent kinase inhibitor 2A (p16), and B-cell lymphoma 2 (bcl-2) showed focal immunoreactivity, estrogen and progesterone were positive, Ki-67 expressed a low proliferation index, whereas p21 and tumor suppressor gene p53 were negative.

Conclusions

The combination of evaluation of conventional morphologic criteria with cyclin-dependent kinase inhibitor 2A (p16), p21, progesterone, B-cell lymphoma 2, tumor suppressor gene p53 and Ki-67 expression may be of great value in the assessment of uterine smooth muscle tumors of uncertain or borderline histology.

Imaging findings of fallopian tube leiomyoma with myxoid degeneration: a case report

Leiomyomas from the fallopian tube are very rare and usually asymptomatic but may cause symptoms by torsion or obstruction. Herein, we describe the detailed imaging findings of tubal leiomyoma with myxoid degeneration. Tubal leiomyoma appeared as a well-defined juxtauterine tumor marginated by low-signal rims with intervening bridging vessels between the tumor and uterus. A tubal mass showing heterogeneous speckled high signals with intermediate signal background on T2-weighted image without diffusion restriction could suggest the probability of tubal leiomyoma with mxoid degeneration.

A giant cystic leiomyoma mimicking an ovarian malignancy

INTRODUCTION

Leiomyoma of the uterus is the most common type of tumor affecting the female pelvis and arises from uterine smooth muscle. The size of leiomyomas varies from microscopic to giant; giant myomas are exceedingly rare. We report an unusual case of a large, cystic, pedunculated uterine leiomyoma mimicking a primary malignant ovarian tumor on sonography and CT.

PRESENTATION OF CASE

A 58-year-old postmenopausal nulliparous woman presented with a history of lower abdominal pain and distension for a period of approximately 12 months. The patient's personal history revealed difficulty in walking, tiredness and recent weight gain of approximately 25 kg. Sonography and CT examination showed a large mass that filled the abdomen. A preoperative diagnosis of a primary malignant ovarian tumor was made. The patient underwent laparotomy, total hysterectomy and bilateral salpingo-ooferectomy. The histology revealed a leiomyoma with extensive cystic degeneration.

DISCUSSION

The current established management of uterine fibroids may involve expectant, surgical, or medical management or uterine artery embolization or a combination of these treatments. A surgical approach is preferred for management of giant leiomyomas.

CONCLUSION

Pedunculated leiomyomas should be considered in the differential diagnosis of a multilocular and predominantly cystic adnexal mass.

Diffusion-weighted imaging in uterine artery embolisation: do findings correlate with contrast enhancement and volume reduction?

OBJECTIVES

The objective of this study was to determine the role of diffusion-weighted imaging (DWI) in uterine artery embolisation (UAE), and to assess the apparent diffusion coefficient (ADC) of the dominant fibroid and its relationship to contrast enhancement and fibroid volume reduction.

METHODS

We carried out a retrospective study of 15 patients who underwent UAE. Calculations were performed at baseline and 6 months post-embolisation. Fibroid ADC (expressed in 10(-3) mm(2) s(-1)) was calculated using b=0 and b=1000 DWI values. Fibroid enhancement was compared with background myometrium by measuring signal-difference-to-noise ratio (SDNR). Fibroid volume was calculated using a prolate ellipse formula.

RESULTS

There was a significant reduction (p<0.001) in fibroid ADC at 6 months (0.48; standard deviation, SD=0.26) as compared with baseline (1.01; SD=0.39). No significant change (p=0.07) was identified in 6-month myometrial ADC (1.09; SD=0.28) as compared with baseline (1.24; SD=0.20). Moderately strong and significant positive correlation was identified between baseline ADC and 6-month percentage volume reduction of the fibroid (correlation=0.66, p=0.007). No correlation was identified between SDNR and ADC at baseline or 6 months (r=0.01, p=0.97 and r=-0.13, p=0.64, respectively) or SDNR and percentage volume reduction at 6 months (correlation r=0.18, p=0.51).

CONCLUSION

Baseline ADC of dominant fibroids shows a moderately strong correlation with subsequent volume reduction at 6 months following UAE. No correlation was identified between ADC values and contrast enhancement on the baseline or 6-month scans. Further prospective evaluation is needed before DWI can be utilised in clinical practice. Advances in knowledge DWI imaging may provide additional information about UAE and possibly help to predict uterine volume reduction.

Uterine smooth-muscle tumors with unusual growth patterns

Uterine smooth-muscle tumors with unusual growth patterns include a variety of neoplastic lesions characterized histologically by their similarity to adult smooth muscle tissue. The 3 primary neoplasms are intravenous leiomyomatosis, benign metastasizing leiomyoma, and leiomyomatosis peritonealis disseminata. We present a review of the recent literature along with the clinical and pathologic features of 5 illustrative cases from Mayo Clinic Arizona, Scottsdale.

Gynecologic pathology on multidetector CT: a pictorial review

The purpose of this pictorial essay is to review the imaging appearance of the spectrum of gynecologic pathology that may be visualized by multidetector computed tomography (CT). Although ultrasound and magnetic resonance imaging remain the primary imaging modalities for evaluating female patients with suspected obstetric and gynecologic pathology, CT is frequently performed as the initial imaging modality in the evaluation of abdominal and pelvic pain of unknown etiology. Pelvic pain in women due to a gynecologic condition may also mimic numerous other conditions such as appendicitis and diverticulitis, resulting in initial evaluation by CT-particularly in the emergency setting. The radiologist should, therefore, be familiar with the spectrum of gynecologic and obstetric pathology that may be present on a CT evaluation of the abdomen and pelvis regardless of the study indication, particularly because CT is often the most readily available imaging modality in the emergency setting on a 24/7 basis.

Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor of uterus

The aim of this paper was to investigate the relationship between the expression of adrenomedullin (ADM) and microvessel density (MVD) and prognosis in smooth muscle tumor of uterus. The expression of ADM was detected using immunohistochemical staining in specimens from 15 normal controls, 28 cases of uterine leiomyoma (LE) and 19 cases of uterine leiomyosarcoma (LES). The MVD was assayed by immunostainting with CD34. There was a positive correlation between the ADM expression and MVD in LE and LES respectively (r s = 0.823, P < 0.01; r s = 0.793, P < 0.01). The expression of ADM in LE was statistically lower than that in LES (P < 0.05). There was a positive correlation between the ADM expression and mitotic figures in LES (P < 0.05): the more mitotic figures, the higher levels of the ADM expression and poor prognosis. The ADM is an important angiogenic factor in smooth muscle tumor of uterus. The ADM can be used as an accessory marker in estimating the malignant potency of LE and judging the prognosis of LES, and as a novel molecular target of anti-angiogenic and anticarcinogenic strategies.

Hormone-dependent gynaecological disorders: a pathophysiological perspective for appropriate treatment

Hormonal changes are involved in several gynaecological disorders. Correct functioning of the hypothalamus-pituitary-ovarian (HPO) axis is critical for ovulatory function, as well as the growth and differentiation of uterine tissue (myometrium and endometrium). However, the correct functioning of other endocrine glands (thyroid, adrenal cortex, pancreas) is also crucial for correct reproductive function. Genes and environmental factors have an influence on women's fertility through their effect on hormonal function. Consequently, dysfunction of the HPO axis and/or other endocrine systems may cause infertility and gynaecological disorders. The pathogenetic basis can be used to help make the correct clinical decision for treating these diseases. Disturbances related to the menstrual cycle, i.e. amenorrhoea, polycystic ovary syndrome (PCOS) and premenstrual syndrome (PMS), have a close correlation with hypo- or hypersecretion of hormones of the HPO axis. The roles of hypothalamic neurohormones and neurotransmitters in the various forms of amenorrhoea and PMS are well established. PCOS has a complex endocrine/metabolic origin, so a variety of hormonal treatments have been proposed. Hormone derangement has also been proposed as the cause of endometriosis and uterine fibroids. These disorders do not have hyper- or hyposecretion of reproductive hormones, but hyperactivity of oestrogen receptors coupled with a genetic predisposition. The relevance of the endocrine changes is confirmed by the clinical effectiveness of hormonal treatments. In order to establish the correct treatment approach in gynaecological disorders, it is important to understand the endocrine pathophysiology.

Is It a Fibroid? Are You Sure?

Uterine fibroids are common benign lesions. Other common benign masses include renal cysts, renal angiomyolipomas, hepatic cysts, hepatic hemangiomas, thyroid cysts, adrenal incidentalomas, pulmonary granulomas and hamartomas, ovarian cysts, and dermoids. All these conditions, especially in asymptomatic patients, almost never have clinical significance. However, it is important to differentiate them from more sinister or even malignant lesions. In general, when a lesion is described as a fibroid, no further evaluation is performed. So if we say that a lesion is a fibroid, we have to be sure. Endometrial fibroids may mimic endometrial polyps or endometrial cancer. Subserous, especially pedunculated fibroids, may need further evaluation to differentiate them from ovarian pathology, colonic pathology, or even müllerian duct anomalies. Pelvic magnetic resonance imaging may be helpful in these cases.

Smooth Muscle Tumors of the Ovary

We studied 54 ovarian smooth muscle tumors with an emphasis on histologic criteria for malignancy. Twenty-two leiomyomas were identified, including 7 typical, 11 cellular, 2 mitotically active, 1 with bizarre nuclei, and 1 myxoid. Follow-up ranging from 12 to 240 months (mean, 77.6 months) was available for 14 patients; all were alive with no evidence of disease. Of 26 leiomyosarcomas, including 2 myxoid leiomyosarcomas, most were readily diagnosed by the presence of at least two of the following: moderate or severe cytologic atypia, mitotic rate > or =10 mitotic figures per 10 high power fields, and tumor cell necrosis. Some cytologically atypical tumors demonstrated lesser mitotic activity of 5 to 9 mitotic figures per 10 high power fields, in the absence of tumor cell necrosis. Sixty percent of these were clinically malignant, supporting a diagnosis of leiomyosarcoma in such tumors. Follow-up was available for 21 patients. Seventy-one percent developed recurrent disease at a mean of 19 months, and 62% died of their disease at a mean of 24 months. Four tumors were deemed of uncertain malignant potential, and two that were stage II both recurred in the pelvis. One case of ovarian intravenous leiomyomatosis had a benign outcome at 42 months, as did one case of ovarian leiomyoma with leiomyomatosis peritonealis disseminata at 180 months. Overall, ovarian smooth muscle tumors encompass the same varied histologic spectrum as their uterine counterparts. The main tumors in the differential diagnosis are those in the fibroma/thecoma category, spindle cell carcinomas, and metastatic gastrointestinal stromal tumors.

Fibroleiomyomas of the tubular genitalia in female beluga whales

Fibroleiomyomas of the tubular genitalia were diagnosed in 6 of 9 adult female beluga whales from the St. Lawrence estuary, Quebec, Canada. These tumors were located in the vagina (6 of 6), the cervix (2 of 6), and the uterus (1 of 6). Endogenous hormones or xeno-estrogens may be implicated in the occurrence of these tumors.

Uterine leiomyomas: histopathologic features, MR imaging findings, differential diagnosis, and treatment

Leiomyomas are the most common uterine neoplasm and are composed of smooth muscle with varying amounts of fibrous connective tissue. As leiomyomas enlarge, they may outgrow their blood supply, resulting in various types of degeneration: hyaline or myxoid degeneration, calcification, cystic degeneration, and red degeneration. Leiomyomas are classified as submucosal, intramural, or subserosal; the latter may become pedunculated and simulate ovarian neoplasms. Although most leiomyomas are asymptomatic, patients may present with abnormal uterine bleeding, pressure on adjacent organs, pain, infertility, or a palpable abdominalpelvic mass. Magnetic resonance (MR) imaging is the most accurate imaging technique for detection and localization of leiomyomas. On T2-weighted images, nondegenerated leiomyomas appear as well-circumscribed masses of decreased signal intensity; however, cellular leiomyomas can have relatively higher signal intensity on T2-weighted images and demonstrate enhancement on contrast material-enhanced images. Degenerated leiomyomas have variable appearances on T2-weighted images and contrast-enhanced images. The differential diagnosis of leiomyomas includes adenomyosis, solid adnexal mass, focal myometrial contraction, and uterine leiomyosarcoma. For patients with symptoms, medical or surgical treatment may be indicated. MR imaging also has a role in treatment of leiomyomas by assisting in surgical planning and monitoring the response to medical therapy.

Cotyledonoid dissecting leiomyoma (Sternberg tumor): an unusual form of leiomyoma

Smooth muscle tumors are the most common neoplasms of the female genital tract. While most are usually easy to diagnose, several variants pose considerable diagnostic difficulties. Recently, a new form of uterine smooth muscle tumor was described that has an infiltrative character, which was named "cotyledonoid dissecting leiomyoma" or "Sternberg tumor" due to its macroscopic similarity to the gross architecture of the placental cotyledon. This report, the second such of this tumor, describes the macroscopic, microscopic, immunohistochemical and ultrastructural features of one of these unusual cases.

Tissue characterization in the female pelvis by means of MR imaging

Pelvic imaging techniques such as computed tomography and ultrasonography provide a limited capability for tissue characterization. Fat, fluid, and calcification, for example, can be identified on the basis of parameters such as x-ray attenuation, echogenicity, and sound attenuation. Because of the many tissue parameters, such as T1, T2, magnetic susceptibility, and chemical shift, that contribute to signal intensity, magnetic resonance (MR) imaging may afford an ability to identify a wider array of specific tissues. The purpose of this article is to review the ability of MR imaging to help identify various types of soft tissue and to provide an approach to interpretation of MR images of the female pelvis through tissue characterization. Lipid, fluid, hemorrhage, smooth muscle, fibrosis, solid malignant tissue, and hydrated soft tissue (including edema, mucin, and myxomatous tissue) have typical MR imaging properties, and their presence in a mass can often be established on MR images. Consideration of the tissue composition of various pathologic processes in the pelvis can result in more systematic approaches to image interpretation and thus narrow the differential diagnosis.