Recent advances in the pathology of smooth muscle tumours of the uterus

Low doses of malathion impair ovarian, uterine, and follicular integrity by altering oxidative profile and gene expression of rats exposed during the peripubertal period

Malathion serves as a pivotal pesticide in agriculture and the management of the Aedes aegypti mosquito. Despite its widespread use, there is a notable absence of studies elucidating the mechanisms through which malathion may affect the female reproductive system. Consequently, the objective of this investigation was to assess whether exposing juvenile female rats to low doses of malathion during the juvenile and peripubertal periods could compromise pubertal onset, estradiol levels, and the integrity of the ovaries and uterus while also examining the underlying mechanisms of damage. To achieve this, thirty juvenile female rats were subjected to either a vehicle or malathion (10 mg/kg or 50 mg/kg) between postnatal days 22 and 60, with subsequent verification of pubertal onset. Upon completion of the exposure period, blood samples were collected for estradiol assessment. The ovaries and uterus were then examined to evaluate histological integrity, oxidative stress, and the expression of genes associated with cell proliferation, antiapoptotic responses, and endocrine pathways. Although estradiol levels and pubertal onset remained unaffected, exposure to malathion compromised the integrity and morphometry of the ovaries and uterus. This was evidenced by altered oxidative profiles and changes in the expression of genes regulating the cell cycle, anti-apoptotic processes, and endocrine pathways. Our findings underscore the role of malathion in inducing cell proliferation, promoting cell survival, and causing oxidative damage to the female reproductive system in rats exposed during peripubertal periods.

Intravenous leiomyomatosis: the first reported case of intraoperative intracaval embolisation of tumour to the right atrium

Intravenous leiomyomatosis is extremely rare. This case describes a 42-year-old woman who presented with abdominal distension, cyclical bloating and urinary retention. Preoperative imaging showed a multilobulated uterine mass. Following multidisciplinary team discussion, a complete staging surgery consisting of midline laparotomy, total hysterectomy and bilateral salpingo-oophrectomy was performed. Intraoperatively, a large multilobulated uterine mass was noted with engorgement of the infundibulopelvic ligaments due to intravascular extension of tumour. On removal of the uterus, the patient desaturated and became hypotensive. Intraoperative transoesophageal echocardiography revealed mass extending from the inferior vena cava (IVC) into the right atrium (RA). The cardiothoracic surgical team retrieved a worm-like mass extending from the IVC into the RA. Histopathological examination diagnosed a large uterine leiomyoma with intravenous leiomyomatosis. The mass from the RA was a bland spindle cell tumour which matched the uterine mass histopathologically. Intravenous leiomyomatosis is a rare variant of uterine leiomyoma. Although intracardiac extension has been described, this is the first case of intraoperative embolisation of pelvic tumour to the RA at hysterectomy.

Clinical experience of uterine smooth muscle tumor of uncertain malignant potential in two gynecological centers: Oncological and obstetrical aspects

OBJECTIVES

To evaluate the clinical characteristics and obstetrical and oncological outcomes of patients with uterine smooth muscle tumors of uncertain malignant potential (STUMP) and analyze the risk factors for recurrence.

STUDY DESIGN

A retrospective cohort study was performed at two gynecological centers using data collected between January 2008 and August 2018. All the patients enrolled were diagnosed with STUMP and had been followed up for at least 6 months. The patients' characteristics, treatment methods, recurrence rate, and subsequent pregnancy outcomes were evaluated.

RESULTS

The mean age of the 62 patients was 36.1 ± 9.1 years (median 35, range 20-55 years) and mean follow-up duration was 36.3 ± 26.8 months (29.5, 6-130). All the patients were of premenopausal status. Fourteen patients (22.6 %) were initially treated by hysterectomy and 48 (77.4 %) by myomectomy. During the study period, three patients (4.8 %) experienced recurrence. However, there was no statistical difference between myomectomy and hysterectomy in terms of the rate of recurrence of STUMP or sarcoma, and all patients survived even after recurrence. Multivariate analysis revealed that a history of previous myomectomy was the sole independent risk factor for recurrence (odds ratio = 51.071; 95 % confidence interval = 2.743-950.726; p = 0.008). Subsequent pregnancies were successful in 10 of 19 women (52.6 %) who tried to conceive. Two of them had ongoing pregnancies at the time of last follow-up; the remaining eight women experienced a total of 14 subsequent pregnancies.

CONCLUSIONS

The recurrence rate of STUMP was similar between hysterectomy and myomectomy. Therefore, fertility sparing myomectomy can be considered in women diagnosed with STUMP with close monitoring.

Prognostic factors and the role of pelvic lymphadenectomy in uterine leiomyosarcomas

Objectives:

Leiomyosarcomas are relatively rare uterine smooth muscle tumors. Surgery is the most common therapy choice for uterine leiomyosarcomas. However, controversy exists over the appropriate initial surgical management, especially about the role of lymph node sampling. The aim of our study is to analyze the prognostic factors and the role of lymphadenectomy in overall survival and in disease-free survival.

Methods:

We analyzed retrospectively 31 patients suffering from uterine leiomyosarcomas at Institute of Salah Azaiez during 2000–2014. Demographic and clinical features such as age, menopausal status, stage, tumor size, and management options were examined, and pathological characteristics such as mitotic count, lymphovascular space invasion, and tumor necrosis were evaluated.

Results:

Out of 31 patients treated for uterine leiomyosarcomas, pelvic lymphadenectomy was done for 18 patients. No para-aortic lymphadenectomy was performed. Median number of resected lymph nodes was 13 ± 7 (range: 3–27). Lymphatic metastasis was observed in 2 out of 18 patients with clinical stage IA and IIIB. The distribution of different variables (age, International Federation of Gynecology and Obstetrics stage, tumor size, mitotic count, and adjuvant treatment) between the group of patients, who had or had not lymphadenectomy done, had no significant difference. The 5-year overall survival and disease-free survival were 61% and 50%, respectively. Clinical stage, presence of lymphovascular space invasion, and lymph nodal dissection were found to be relevant for disease-free survival on univariate analysis. Only age and menopausal status were found to be a prognostic factor for overall survival.

Conclusion:

Hence, routine lymph node dissection was not generally recommended. Our study demonstrates that lymphadenectomy has a statistically significant effect on disease-free survival but not on overall survival.

Parasitic leiomyomas: a systematic review

BACKGROUND

Parasitic leiomyomas were first described as early as 1909 but are a rare condition. In recent years, due to the rise of laparoscopic surgery and power morcellation, several cases of parasitic leiomyomas associated with this surgical procedure have been reported.

METHODS

A literature search was performed using PubMed, Embase and Google Scholar with the following combination of keywords: leiomyoma OR uterine neoplasms OR uterine myomectomy OR laparoscopy OR hysterectomy OR peritoneal neoplasms AND parasitic. Papers describing parasitic leiomyomas were included. The results of these studies are summarized herein.

RESULTS

We retrieved abstracts of 756 papers. Of these, 591 were excluded for not fulfilling the inclusion criteria and 54 were removed as duplicates; after full-text assessment, 8 were rejected for presenting cases of malignancy and finally 103 were included in our systematic review. From these, we present information about 274 patients with parasitic leiomyomas. The mean age of women was 40 years (range 18-79 years); and 154 (56%) had no history of uterine surgery, the others (120, 44%) having had a previous myomectomy or hysterectomy. Of the total, 106 (39%) women had a history of power morcellation. The most frequent clinical symptom was abdominal pain (49%) and the most frequent presentation was disseminated peritoneal leiomyomatosis.

CONCLUSIONS

While parasitic leiomyoma was first described a century ago, the recent introduction of laparoscopic power morcellation has increased the number of reported cases.

Massive Broad Ligament Cellular Leiomyoma with Cystic Change: A Diagnostic Dilemma

Leiomyomas are known to arise from uterus, but rarely from broad ligament. Further, cellular leiomyoma of broad ligament is the least common variant reported in literature. The diagnostic dilemma arises when leiomyomas undergo degenerative changes. This poses both clinical and radiological difficulty in differentiating with an ovarian tumour. We present an unusual case of a huge broad ligament mass measuring 29x19x09cm, mimicking an ovarian tumour both clinically and radiologically. Histopathology revealed cellular leiomyoma of broad ligament with cystic and myxoid degeneration hereby being the second case reported in literature. This case is being presented not only because of the rare incidence but also due to its diagnostic confusion with ovarian malignancy on clinical evaluation and radiological findings.

Intravenous leiomyomatosis: an unusual intermediate between benign and malignant uterine smooth muscle tumors

Intravenous leiomyomatosis is an unusual smooth muscle neoplasm with quasi-malignant intravascular growth but a histologically banal appearance. Herein, we report expression and molecular cytogenetic analyses of a series of 12 intravenous leiomyomatosis cases to better understand the pathogenesis of intravenous leiomyomatosis. All cases were analyzed for the expression of HMGA2, MDM2, and CDK4 proteins by immunohistochemistry based on our previous finding of der(14)t(12;14)(q14.3;q24) in intravenous leiomyomatosis. Seven of 12 (58%) intravenous leiomyomatosis cases expressed HMGA2, and none expressed MDM2 or CDK4. Colocalization of hybridization signals for probes from the HMGA2 locus (12q14.3) and from 14q24 by interphase fluorescence in situ hybridization (FISH) was detected in a mean of 89.2% of nuclei in HMGA2-positive cases by immunohistochemistry, but in only 12.4% of nuclei in negative cases, indicating an association of HMGA2 expression and this chromosomal rearrangement (P=8.24 × 10(-10)). Four HMGA2-positive cases had greater than two HMGA2 hybridization signals per cell. No cases showed loss of a hybridization signal by interphase FISH for the frequently deleted region of 7q22 in uterine leiomyomata. One intravenous leiomyomatosis case analyzed by array comparative genomic hybridization revealed complex copy number variations. Finally, expression profiling was performed on three intravenous leiomyomatosis cases. Interestingly, hierarchical cluster analysis of the expression profiles revealed segregation of the intravenous leiomyomatosis cases with leiomyosarcoma rather than with myometrium, uterine leiomyoma of the usual histological type, or plexiform leiomyoma. These findings suggest that intravenous leiomyomatosis cases share some molecular cytogenetic characteristics with uterine leiomyoma, and expression profiles similar to that of leiomyosarcoma cases, further supporting their intermediate, quasi-malignant behavior.

Epidemiological and genetic clues for molecular mechanisms involved in uterine leiomyoma development and growth

BACKGROUND

Uterine leiomyomas (fibroids) are highly prevalent benign smooth muscle tumors of the uterus. In the USA, the lifetime risk for women developing uterine leiomyomas is estimated as up to 75%. Except for hysterectomy, most therapies or treatments often provide only partial or temporary relief and are not successful in every patient. There is a clear racial disparity in the disease; African-American women are estimated to be three times more likely to develop uterine leiomyomas and generally develop more severe symptoms. There is also familial clustering between first-degree relatives and twins, and multiple inherited syndromes in which fibroid development occurs. Leiomyomas have been described as clonal and hormonally regulated, but despite the healthcare burden imposed by the disease, the etiology of uterine leiomyomas remains largely unknown. The mechanisms involved in their growth are also essentially unknown, which has contributed to the slow progress in development of effective treatment options.

METHODS

A comprehensive PubMed search for and critical assessment of articles related to the epidemiological, biological and genetic clues for uterine leiomyoma development was performed. The individual functions of some of the best candidate genes are explained to provide more insight into their biological function and to interconnect and organize genes and pathways in one overarching figure that represents the current state of knowledge about uterine leiomyoma development and growth.

RESULTS

In this review, the widely recognized roles of estrogen and progesterone in uterine leiomyoma pathobiology on the basis of clinical and experimental data are presented. This is followed by fundamental aspects and concepts including the possible cellular origin of uterine fibroids. The central themes in the subsequent parts are cytogenetic aberrations in leiomyomas and the racial/ethnic disparities in uterine fibroid biology. Then, the attributes of various in vitro and in vivo, human syndrome, rodent xenograft, naturally mutant, and genetically modified models used to study possible molecular mechanisms of leiomyoma development and growth are described. Particular emphasis is placed on known links to fibrosis, hypertrophy, and hyperplasia and genes that are potentially important in these processes.

CONCLUSIONS

Menstrual cycle-related injury and repair and coinciding hormonal cycling appears to affect myometrial stem cells that, at a certain stage of fibroid development, often obtain cytogenetic aberrations and mutations of Mediator complex subunit 12 (MED12). Mammalian target of rapamycin (mTOR), a master regulator of proliferation, is activated in many of these tumors, possibly by mechanisms that are similar to some human fibrosis syndromes and/or by mutation of upstream tumor suppressor genes. Animal models of the disease support some of these dysregulated pathways in fibroid etiology or pathogenesis, but none are definitive. All of this suggests that there are likely several key mechanisms involved in the disease that, in addition to increasing the complexity of uterine fibroid pathobiology, offer possible approaches for patient-specific therapies. A final model that incorporates many of these reported mechanisms is presented with a discussion of their implications for leiomyoma clinical practice.

Cellular leiomyoma with necrosis and mucinous degeneration presenting as pseudo-Meigs' syndrome with elevated CA125

Pseudo-Meigs' syndrome is a syndrome rarely caused by leiomyomas. Elevated CA125 usually suggests malignancy of the ovary. No reported case of pseudo-Meigs' syndrome presenting with necrosis and mucinous degeneration of uterine cellular leiomyomas (CLs) and an elevated CA125 level was found upon a PubMed search. A 37-year-old woman presenting with massive ascites, bilateral pleural effusions and a pelvic mass measuring 20 x 18 x 10 cm is described. The pre-operative serum CA125 was 920.4 U/ml. After total abdominal hysterectomy and partial omentumectomy, the final pathologic diagnosis was CL with focal hemorrhage, necrosis and mucinous degeneration. The ascites and pleural effusion disappeared, and the CA125 level returned to normal in one month. Benign leiomyoma accompanied by pseudo-Meigs' syndrome and elevated serum CA125 can mimic a pelvic malignancy.

The measurement of stiffness of uterine smooth muscle tumor by elastography

Leiomyoma shows various diagnostic images, often making it difficult to differentiate from leiomyosarcoma. Recently, the utility of elastography has been reported for the differentiation of superficial tumors. We attempted to diagnose two cases of uterine smooth muscle tumors by elastography.

One case was strongly suspected of leiomyosarcoma, and the other case had been diagnosed with leiomyoma. We preoperatively performed virtual tissue imaging (VTI) and virtual tissue quantification (VTQ). In VTQ, we measured shear wave velocity (Vs) five times at each point that ROI was placed. In case of suspected leiomyosarcoma, we attached the tip of convex probe 2 cm below the navel, perpendicular to the floor and measured Vs. In case of leiomyoma, we placed four ROIs randomly in leiomyomas for VTQ. For the case of suspected leiomyosarcoma, Vs and pathological findings from the VTQ were comparably examined. Significant differences were observed in the Vs in the leiomyosarcoma case, whereas not in the leiomyoma case. The comparison of VTQ and pathological findings for the case of leiomyosarcoma indicated high viability in the region where the highest Vs was measured, and strong necrosis in the region with the lowest Vs. These findings suggest that VTQ is useful for diagnosing uterine smooth muscle tumors.

Uterine cellular leiomyomata with chromosome 1p deletions represent a distinct entity

OBJECTIVE

This study aimed to determine whether 1p deletion defines a subset of cellular leiomyomata (CL), which is a hypercellular variant of uterine leiomyomata that may have delayed malignant potential, and to correlate this genetic change with clinical and pathologic characteristics including those present in uterine sarcomas.

STUDY DESIGN

Available CL cases at the Mayo Clinic (n = 101) and variant cases reported in another article (n = 16) were identified. Each case with sufficient tissue that met histologic criteria for CL when reviewed by a single pathologist underwent interphase fluorescence in situ hybridization to determine the presence of 1p deletion. Clinical characteristics of women with confirmed CL were compared on the basis of 1p deletion status using univariate analysis.

RESULTS

Of the Mayo Clinic cohort of histologically confirmed CL, 23% had deletion of 1p. Women with this subset of CL, when compared to those without 1p deletion, were more likely to be postmenopausal (P = .049) and their uteri tended to be heavier (P = .039) with a larger dominant leiomyoma (P = .030). The pathologic features associated with 1p deletion were high cellularity (P = .036) and hyaline necrosis (P = .047), which remained significant after inclusion of the CL cases from a previously published series.

CONCLUSION

Deletion of 1p occurs in approximately one-quarter of CL cases. This genetic alteration is potentially associated with clinicopathologic features that are present in uterine sarcomas, which suggests a distinct clinical entity that may have malignant potential. Our findings are particularly pertinent considering the increased preference for uterine-sparing options in leiomyoma treatment, suggesting assessment of 1p deletion status in CL may influence clinical surveillance decisions.

Estrogen and Progesterone Receptors Expression in Uterine Malignant Smooth Muscle Tumors: Correlation with Clinical Outcome

Uterine leiomyosarcomas are associated with a poor prognosis, although a considerable diversity in behavior may be found, and prolonged survival may occur. The aim of this study was to analyze the expression of estrogen (ER) and progesterone (PR) receptors in tumor specimens from uterine leiomyosarcomas, and to test their correlation with disease-free interval and cause-specific survival. This additional information may help the clinician differentiate between patients who have minimal risk of recurrence and those at greater risk of developing progressive disease. We examined specimens from 31 uterine leiomyosarcoma patients with clinical history and known follow-up. Disease-free interval and cause-specific survival rates were calculated according to the Kaplan-Meier method. According to univariate analysis, with Cox proportional hazards models, the ER expression (P=0.006 and P=0.016, respectively), PR expression (P=0.005 and P=0.016, respectively), and FIGO stage disease (P=0.011 and P=0.007, respectively) were independent predictors of the risk of recurrence and death from disease.

Clinical and pathological characteristics, pathological reevaluation and recurrence patterns of cellular leiomyomas: a retrospective study in 76 patients

OBJECTIVES

To analyze clinical and pathologic features as well as recurrence patterns of cellular leiomyomas (CL) in women who underwent surgical therapy for symptomatic disease.

STUDY DESIGN

This retrospective study was conducted at the Department of Obstetrics and Gynecology, University Women's Clinic, Tuebingen, Germany. We identified all women who had CL on final diagnosis after surgery between January 1, 2000, and December 31, 2010.

RESULTS

Our study sample comprised 76 women with a diagnosis of CL. A single uterine mass was present in 51.3% of the cases; in uteri with both CL and uterine leiomyomas (UL), the CL constituted the largest uterine mass in 20 of 21 (95.2%) cases. Additionally, in 98% of the uteri, CL were either the largest or the only uterine mass. Five women (6.6%; 5/76) had reported surgical procedures for symptomatic leiomyoma before the index surgery in our analysis. Three women underwent hysteroscopic resection of the leiomyomas and 2 women underwent abdominal myomectomy. Mean time to recurrence was 14.0 months (median 6.0; range, 4.0-52.0). Over the follow-up period, 6 women who underwent uterus-conserving surgery (12.0%; 6/50) with CL had leiomyoma recurrence. Five women underwent abdominal myomectomy and one underwent hysteroscopic resection of the CL. One patient had recurrence of a CL 43 months after abdominal myomectomy and underwent vaginal hysterectomy; the other five women had recurrences of UL. Mean time to recurrence was 28.6 months (median 12.5; range, 4.0-83.0).

CONCLUSIONS

Recurrence rates of CL in our study group resemble recurrence rates of UL.

Understanding cellular leiomyomas: a case-control study

OBJECTIVE

Reports exist in which cellular leiomyomas (CLs) appear to have clinical characteristics or genetic profiles similar to leiomyosarcomas. This study aimed to determine whether most CLs differ clinically from typical uterine leiomyomas (ULs).

STUDY DESIGN

A case-control study was conducted with women who underwent surgical procedures between January 1989 and December 2008 and who were diagnosed with a CL (n = 99). Control subjects, who were matched in a 2:1 ratio, were women with a diagnosis of UL (n = 198). Hospital and ambulatory records were reviewed.

RESULTS

In multivariable logistic regression analyses, women with CLs were more likely to have surgery for the indication of enlarging leiomyoma and less likely to have concomitant endometriosis or adenomyosis. Uteri that contained CLs were also more likely to have larger and fewer leiomyomas when compared with control subjects.

CONCLUSION

CLs have a distinct clinical phenotype compared with ULs and have some characteristics in common with leiomyosarcomas.

Molecular and immunohistochemical evidence for the origin of uterine leiomyosarcomas from associated leiomyoma and symplastic leiomyoma-like areas

It is uncertain whether uterine leiomyosarcoma arises de novo or in preexisting leiomyoma. Leiomyoma-like areas can be seen associated with uterine leiomyosarcoma, raising the possibility of precursor lesions for uterine leiomyosarcoma. In this study, we examined cases of uterine leiomyosarcoma associated with leiomyoma-like areas at the histological, immunohistochemical and DNA level to further evaluate if benign-looking leiomyoma-like and uterine leiomyosarcoma areas are related. Cases of uterine leiomyosarcoma observed at the New York University Medical Center from 1994 to 2007 were reviewed for the presence of leiomyoma-like areas. Of the 26 cases of uterine leiomyosarcoma observed during this period, 18 cases had an associated leiomyoma-like area (five cellular leiomyoma, four symplastic leiomyoma, four cellular and symplastic leiomyoma and five usual type leiomyoma). Sixteen of the 18 cases were examined immunohistochemically for Ki-67, for estrogen receptor, progesterone receptor and for p53. Immunohistochemical profiles were as expected for leiomyoma-like (the mean expression of p53, ER, PR and Ki-67 at 0.3, 63, 75 and 0.6%, respectively), symplastic leiomyoma-like areas (the mean expression of p53, ER, PR and Ki-67 at 0.6, 85, 89 and 5.5%, respectively) and uterine leiomyosarcoma areas (the mean expression of p53, ER, PR and Ki-67 at 52, 38, 39 and 61%, respectively). In six cases, the leiomyoma-like and uterine leiomyosarcoma areas from each case were examined using high-density oligonucleotide array-CGH to determine genetic aberrations in the two areas. Nearly all the genetic aberrations found in leiomyoma-like areas were also found in the corresponding uterine leiomyosarcoma areas. In addition, uterine leiomyosarcoma areas had additional genetic aberrations. The immunohistochemical profiles and genetic aberrations of the examined cases suggest that uterine leiomyosarcoma could arise from the preexisting leiomyoma-like areas that often have a symplastic or cellular morphology.

Treatment of early uterine sarcomas: disentangling adjuvant modalities

Uterine sarcomas are a rare group of neoplasms with aggressive clinical course and poor prognosis. They are classified into four main histological subtypes in order of decreasing incidence: carcinosarcomas, leiomyosarcomas, endometrial stromal sarcomas and "other" sarcomas. The pathological subtype demands a tailored approach. Surgical resection is regarded as the mainstay of treatment. Total abdominal hysterectomy and bilateral salpingo-oophorectomy represents the standard treatment of uterine sarcomas. Pelvic and para-aortic lymph node dissection in carcinosarcomas is recommended, given their high incidence of lymph node metastases, and may have a role in endometrial stromal sarcomas. Adjuvant radiation therapy has historically been of little survival value, but it appears to improve local control and may delay recurrence. Regarding adjuvant chemotherapy, there is little evidence in the literature supporting its use except for carcinosarcomas. However, more trials are needed to address these issues, especially, their sequential application. Patients with uterine sarcomas should be referred to large academic centers for participation in clinical trials.

Smooth muscle tumors of the uterus: a practical approach

Smooth muscle tumors (SMTs) are the most frequent mesenchymal tumors of the uterus. The majority of the uterine SMTs are readily classificable as benign or malignant based on their gross and microscopic appearances. However, when unusual features are seen in some leiomyoma variants, the differential diagnosis with a leiomyosarcoma may become challenging. Moreover, diagnostic criteria for the different subtypes of leiomyosarcoma are not uniform. Finally, non-smooth muscle tumors that originate in the uterus may show overlapping histologic and even immunohistochemical features with uterine SMTs, more commonly with the spindle and epithelioid variants, complicating their correct classification. The diagnosis of malignant uterine SMTs has important prognostic and therapeutic implications. This review provides a practical approach to the diagnosis of uterine leiomyosarcoma based on a systematic assessment of histologic parameters as well as a systematic approach to its differential diagnosis based on histologic and immunohistochemical features.

Can gray-scale and color Doppler sonography differentiate between uterine leiomyosarcoma and leiomyoma?

PURPOSE

To evaluate the role of gray-scale and color Doppler sonography to distinguish uterine leiomyosarcoma (LMS) from leiomyoma (LM).

METHODS

We analyzed the preoperative gray-scale and color Doppler sonographic findings of 8 patients with LMS, 21 patients with cellular leiomyomas, and 3 patients with smooth muscle tumors of uncertain malignant potential and compared these findings to 225 patients with benign LM. All patients underwent myomectomy or hysterectomy. Number, size, echotexture, degenerative changes, and vascularity (central or peripheral; absent, mild, moderate, or marked) were recorded and correlated to the histologic findings

RESULTS

LMSs were significantly larger than other uterine smooth muscle tumors. They were all solitary, and 7/8 lesions had a diameter >or=8 cm. Degenerative cystic changes were observed in 4 lesions, and increased peripheral and central vascularity was demonstrated in 7 lesions. Sensitivity, specificity, and positive predictive value of increased central and peripheral vascularity in the diagnosis of LMS were 100%, 86%, and 19%, respectively. Combining other sonographic findings with marked central vascularity, positive predictive value increased to 60%, but sensitivity decreased to 75%.

CONCLUSION

The findings of the present study suggest that the detection of hypervascularity in combination with other sonographic findings can identify suspicious uterine smooth muscle tumors that will require additional diagnostic evaluation before treatment.

The management of patients with uterine sarcoma: a debated clinical challenge

Uterine sarcomas include a heterogeneous group of rare tumours that usually have an aggressive clinical behaviour and a poor prognosis. Total abdominal hysterectomy and bilateral salpingo-oophorectomy represents the standard surgical treatment. Pelvic and/or para-aortic lymphadenectomy is indicated for carcinosarcoma, but not for leiomyosarcoma and undifferentiated endometrial sarcoma. Some recent data on low numbers of patients with low-grade endometrial stromal sarcoma appear to show an incidence of nodal involvement higher than previously expected, thus suggesting a role for lymphadenectomy in this malignancy. Carcinosarcoma also requires a comprehensive surgical peritoneal staging. Postoperative treatment of uterine sarcomas has been long debated. Adjuvant pelvic radiotherapy appears to improve local control without any significant impact on overall survival. There is little evidence in the literature supporting the use of adjuvant chemotherapy in any gynaecological sarcomas except for carcinosarcomas. However, uterine sarcomas have a high tendency to develop distant recurrences, and recent data on adjuvant chemotherapy in soft tissue sarcomas are promising. As for the drugs to be used, it is worth noting that in a Swiss study, the combination of ifosfamide (IFO) and doxorubicin (DOX) obtained similar response rates in advanced gynaecological sarcomas and in advanced soft tissue sarcomas of other sites. In our decision-making scheme for early-stage disease, patients with leiomyosarcoma or undifferentiated endometrial sarcoma should receive adjuvant doxorubicin/epidoxorubicin (EPIDX)+ifosfamide, and those with carcinosarcoma should be treated with adjuvant cisplatin (CDDP)-based chemotherapy. The same drug regimens are used for the treatment of advanced disease. Sequential pelvic radiotherapy following chemotherapy could be delivered to selected cases. Recurrent disease often requires the integration of different therapeutic modalities, but no curative option is currently available with the possible exception of surgery for lung metastases and hormone therapy with or without debulking surgery for recurrent low-grade endometrial stromal sarcoma. Patients should be encouraged to enter clinical trials designed to identify new active drugs for these malignancies.

Multinodular leiomyoma of the esophagus with internodular hydropic degeneration and bulbous serosal protrusions similar to cotyledonoid uterine leiomyoma

Leiomyoma is the most common benign tumor of the esophagus, and usually occurs as a solitary mass. We report a case of esophageal leiomyoma which shows multinodular growth pattern with bulbous serosal protrusions. The patient was a 26-year-old woman who had an esophageal ulcerated mass near the gastroesophageal junction. Clinical findings were consistent with carcinoma of the gastric cardia. Based on the clinical diagnosis, total gastrectomy with distal esophagectomy was performed. Histologic appearance of the resected specimen was consistent with leiomyoma which had a multinodular growth pattern.

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.

The Endometrium

Context.—Endometrial tissue specimens are commonly encountered in daily practice. It is well known that a number of problematic diagnostic scenarios occur relative to these specimens.

Objective.—To emphasize practical aspects of endometrial specimen handling and reporting, with selected comments on common diagnostic pitfalls, including (1) the diagnosis of endometrial intraepithelial carcinoma in atrophic endometrial biopsy specimens, (2) evaluation of adequacy of endometrial sampling specimens, (3) problems in diagnosing and measuring the depth of myometrial invasion in endometrial carcinoma, (4) the question of metastasis versus independent primaries in concurrent carcinomas of endometrium and one or both ovaries, (5) the problematic differential diagnoses between type 1 (primarily endometrioid) and type 2 (primarily serous) adenocarcinomas, and (6) atypical hyperplasia and proposed classification systems for its replacement.

Data Sources.—Published literature, consensus statements, and personal experience.

Conclusions.—A systematic approach to the handling and reporting of endometrial specimens reduces the potential for omission and error. Recognition of diagnostic pitfalls and practical approaches to their resolution help improve quality.

Uterine smooth-muscle tumors with unusual growth patterns: imaging with pathologic correlation

OBJECTIVE

This essay illustrates the salient features of variant smooth-muscle tumors on multiple imaging techniques with correlative pathology. We describe how recognition of these features allows the radiologist to distinguish a uterine leiomyoma variant from the classic fibroid or a leiomyosarcoma. Finally, we highlight the role of the radiologist in triaging these patients to surgical versus medical management and in surgical planning.

CONCLUSION

Parasitic leiomyoma, intravenous leiomyomatosis, disseminated peritoneal leiomyomatosis, and benign metastasizing leiomyoma show key features on multiple imaging techniques that correlate with pathology findings. In the appropriate clinical setting, the radiologist should include these unusual lesions in the broader differential diagnosis of smooth-muscle tumors and, in certain cases, aid in surgical planning.

Uterine leiomyoma versus leiomyosarcoma: a new attempt at differential diagnosis based on their cellular characteristics

AIM

To differentiate uterine leiomyoma (LM) with 'pseudosarcomatous' features from leiomyosarcoma (LMS). We hypothesized that because pseudosarcomatous LM is only a benign variant of conventional LM, it may have some characteristics different from LMS.

METHODS AND RESULTS

Fourteen uterine smooth muscle tumours, which had been diagnosed as LMS previously, were reviewed and divided into adverse outcome (true LMS; seven cases) and excellent outcome groups (presumed pseudosarcomatous LM; seven cases) based on their clinical course. The tumours of the adverse outcome group were composed of rather uniform long spindle cells similar to those of leiomyosarcoma arising from the soft tissue. All tumours in this group had coagulative necrosis and all but one case were diagnosed preoperatively as malignant. In contrast, the tumours of the excellent outcome group showed significant histological diversity both between tumours and also in the same tumour and areas indistinguishable from conventional LM were often seen. All the tumours of this group were diagnosed preoperatively as benign. Immunohistochemically, all tumours of the excellent outcome group expressed progesterone receptor, often intensely, and also frequently expressed oestrogen receptor. In contrast, all the tumours of the adverse outcome group lacked them completely.

CONCLUSION

Pseudosarcomatous LM has characteristics useful for differentiating it from LMS, which are common in conventional LM.

Observing three-dimensional human microvascular and myogenic architecture using conventional fluorescence microscopy

Microangiography and vascular casting have previously been used to demonstrate the three-dimensional architecture of human uterine microvasculature. However, a limitation of these perfusion-dependent techniques is the difficulty in identifying surrounding tissue components. We have previously shown that it is possible to visualise microvascular networks on the cut surfaces of fresh tissue specimens by diffusive labelling of vascular endothelium with fluorescently conjugated UEA-1 lectin. Unlike perfusion methods that are limited to accessible vascular networks, diffusive fluorescence labelling (DFL) allows additional visualisation of extravascular cellular components, such as smooth muscle. Following UEA-1 DFL, smooth muscle-myosin and -actin were then visualised by immunolocalisation on the acetone-fixed tissue pieces. This allowed clear three-dimensional distinction between the vascular and muscle architecture of the myometrium and endometrium. This method can also be applied for studying the relative distribution of microvascular and muscle architecture in leiomyomas (fibroids). The techniques described in this methodological study provide a simple way of directly examining the uterine vasculature in three dimensions using conventional microscopy, while also distinguishing myometrial from endometrial parts of the network.

Les tumeurs musculaires lisses de l’utérus

INTRODUCTION

Smooth muscle tumors of the uterus are frequent. Most of them are benign. Some leiomyomas may have unusual morphologic features difficult to distinguish from leiomyosarcoma. These tumors are: cellular leiomyoma, atypical leiomyoma and mitotically active leiomyoma.

OBJECTIVES

The purpose of our work is to study cases of leiomyosarcomas, cellular leiomyoma, atypical leiomyoma and mitotically active leiomyoma among a large series of uterine smooth muscle tumors.

MATERIALS AND METHODS

We reviewed retrospectively 2760 uterine smooth muscle tumors. The slides were reviewed and the tumors reclassified according to the criteria of the WHO 2003 classification. Chi-square test or Fisher's exact were used for statistical analyses as appropriate.

RESULTS

Review of the slides demonstrated: 12 mitotically active leiomyomas, 18 cellular leiomyomas, 20 atypical leiomyomas, 16 leiomysarcomas, only one case of smooth muscle tumor of uncertain malignant potential. The 2709 remaining tumors were all common leiomyomas. So mitotically active, cellular and atypical leiomyomas were as rare as the leiomyosarcomas. The average age of patients with leiomyomas was 39 years. That of patients with leiomyosarcomas was 54 years (p=0,000002). Average size of leiomyomas was 7.4cm. That of leiomyosarcomas was 10.2cm. The average age and size of the 3 studied variants of leiomyomas were identical to those of the common leiomyomas. Leiomyomas were unique in 60.9% of cases. On the other hand 87.5% of leiomyosarcomas had unique nodules (p=0,04).

No evidence for epigenetic inactivation of fumarate hydratase in leiomyomas and leiomyosarcomas

Germline mutations in Fumarate Hydratase (FH) cause the development of leiomyomas and leiomyosarcomas in the syndromes Multiple Cutaneous and Uterine Leiomyomata (MCUL1) and Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC). There is little evidence, however, that FH mutation plays a role in the development of sporadic leiomyomas or leiomyosarcomas. Such observations do not, however, exclude a role for FH in tumour development outside the context of MCUL1/HLRCC, as it is possible that FH expression could be silenced by epigenetic mechanisms. To explore this possibility we have developed a highly specific antibody to FH and analysed a series of forty-five fresh-frozen uterine leiomyomas and nine leiomyosarcomas for FH expression.

Pediatric gastrointestinal stromal tumors and leiomyosarcoma

BACKGROUND

With the introduction of molecularly targeted therapy for gastrointestinal stromal tumors (GISTs), it became important to distinguish GISTs from leiomyosarcomas (LMSs). The authors sought to characterize the clinicopathologic features of these tumors in pediatric patients.

METHODS

The authors reviewed the medical records of 11 patients for whom GIST or LMS was diagnosed between March 1962 and July 2002 at St. Jude Children's Research Hospital and reclassified the tumors according to current histologic and immunophenotypic criteria. The authors also reviewed the literature pertaining to pediatric GISTs and LMSs.

RESULTS

Seven patients had GISTs, and four had LMS. The median age of the patients at diagnosis was 11.5 years. At diagnosis, metastases were present in one patient with GISTs and in another with LMS. Unlike the focal distribution of CD117 (KIT) in LMS, diffuse and strong immunostaining was observed in GISTs. Only GISTs expressed CD34. Six patients underwent complete resection (four with GISTs and two with LMS), four patients underwent incomplete resection (three with GISTs and one with LMS), and one patient (with LMS) underwent a biopsy only. Radiotherapy or chemotherapy was used to treat one patient with GISTs and three patients with LMS. One patient with a high-risk GIST (largest dimension of 32 cm and high mitotic count) was treated with adjuvant imatinib mesylate outside the preferred setting of a clinical trial, due to concerns regarding the high risk of tumor recurrence. Four patients with GISTs and two with LMS survived median disease-free a median of 10.4 years and 4.3 years after diagnosis, respectively. Tumors in all but one survivor were completely resected.

CONCLUSIONS

KIT staining helped to distinguish GISTs from LMSs. Surgery was the treatment of choice for both entities, and tumor resectability was a key prognostic factor.

A glance at adenosine receptors: novel target for antitumor therapy

Adenosine can be released from a variety of cells throughout the body, as the result of increased metabolic rates, in concentrations that can have a profound impact on the vasculature, immunoescaping, and growth of tumor masses. It is recognized that the concentrations of this nucleoside are increased in cancer tissues. Therefore, it is not surprising that adenosine has been shown to be a crucial factor in determining the cell progression pathway, either during apoptosis or during cytostatic state. From the perspective of cancer, the most important question then may be "Can activation and/or blockade of the pathways downstream of the adenosine receptor contribute to tumor development?" Rigorous examinations of the role of adenosine in in vivo and in vitro systems need to be investigated. The present review therefore proposes multiple adenosine-sustained ways that could prime tumor development together with the critical combinatorial role played by adenosine receptors in taking a choice between proliferation and death. This review proposes that adenosine acts as a potent regulator of normal and tumor cell growth. It is hypothesized that this effect is dependent on extracellular adenosine concentrations, cell surface expression of different adenosine receptor subtypes, and signal transduction mechanisms activated following the binding of specific agonists. We venture to suggest that the clarification of the role of adenosine and its receptors in cancer development may hold great promise for the treatment of chemotherapy in patients affected by malignancies.

Functional genomics guided with MR imaging: mouse tumor model study

To gain a better understanding of gene expression patterns in tumors, the authors used contrast material-enhanced magnetic resonance (MR) imaging to noninvasively characterize regions within the same tumor to provide a correlate for genomic analysis. Gene expression profiles of samples from a mouse tumor model obtained from contrast-enhanced and nonenhanced regions within the same tumor were compared with MR imaging and functional genomics. From these samples, 11000 genes were analyzed: 10 genes were up-regulated in the contrast-enhanced areas, and one gene was up-regulated in the nonenhanced regions. Several of these genes encode extracellular matrix proteins. Findings in this study demonstrate that MR imaging can serve as a powerful noninvasive tool for characterizing different regions of tumors to guide genomic analysis with high spatial and temporal resolution.

DNA hypomethylation and imbalanced expression of DNA methyltransferases (DNMT1, 3A, and 3B) in human uterine leiomyoma

OBJECTIVE

Despite the high prevalence of uterine leiomyoma in women, little is known about the pathophysiology of this tumor. This study intends to define the epigenetic modulation of this tumor.

METHODS

Twenty-three pairs of leiomyomas and their adjacent myometria were collected. Status of DNA global methylation was determined by using DNA methyl acceptance assay and immunohistochemistry staining with 5-methylcytidine antibody. MRNA level of DNA methyltransferases (DNMT1, 3A, and 3B) was assessed by quantitative real time PCR.

RESULTS

DNA global hypomethylation was detected in the leiomyoma tissues as compared with the adjacent myometria. DNMT1 expression was increased in 47.5% and was equal in 47.5% in leiomyomas compared to the adjacent myometria. On the other hand, over 74% of cases showed decreased expression of DNMT3A and 3B in leiomyomas compared to the adjacent myometria.

CONCLUSION

Global hypomethylation and imbalanced expression of DNMTs in uterine leiomyoma suggested a potential mechanism of epigenetic modulation in the development of this tumor.

Leiomyoblastoma of the uterus: an immunohistochemical and electron microscopic study of distinctive tumours with immature smooth muscle cell differentiation mimicking fetal uterine myocytes

AIMS

We present three distinctive uterine tumours which exhibited immature smooth muscle differentiation mimicking smooth muscle cells of the fetal uterus.

METHODS AND RESULTS

The patients were 45, 46 and 49 years old, and all of them had simple hysterectomies. Grossly, all tumours were present in the uterine body, and two of the three tumours were well demarcated 60-mm and 85-mm lesions, and the other tumour was a small 25-mm incidental lesion within multiple conventional leiomyomas. The tumours had varied histological features and were composed of round epithelioid, rhabdoid and large vacuolated cells intermingled with spindle-shaped cells to various degrees. Although their round vesicular nuclei showed mild to moderate variation in size, prominent nuclear atypia was not seen. Necrosis and mitotic figures suggesting biological aggressiveness were not present in any of the tumours. Immunohistochemically, tumour cells were intensely positive for desmin and alpha-smooth muscle actin, whereas positivity for heavy molecular weight caldesmon was restricted. In addition, two cases were positive for non-muscle myosin heavy chain (SMemb). Ultrastructurally, most tumour cells contained various amounts of intermediate filaments which were occasionally abundant and aggregated as in rhabdoid cells. Well-developed myofilaments with focal densities were observed in only a few tumour cells. Intermediate filaments and bundles of thin filaments without dense bodies were often intermingled and they occasionally formed distinctive complexes with many irregular dense body-like structures and crystalloid bodies. Other cytoplasmic organelles including rather rich mitochondria, some rough endoplasmic reticulum and free ribosomes were also common.

CONCLUSIONS

These findings support their immature smooth muscle cell differentiation which mimics the mesenchymal cells of fetal uterus during 14-26 weeks of gestation. The term 'uterine leiomyoblastoma' is thought to be appropriate for describing these distinctive immature smooth muscle tumours.

Sinonasal smooth muscle cell tumors: a clinicopathologic and immunohistochemical analysis of 12 cases with emphasis on the low-grade end of the spectrum

CONTEXT

Smooth muscle tumors (SMTs) of the sinonasal tracts are very rare mesenchymal neoplasms, and the literature includes very limited data correlating histologic parameters with clinical outcome. As the behavior of SMTs is site-dependent, defining applicable criteria to distinguish among low-grade leiomyosarcoma, SMT of uncertain malignant potential (SMTUMP), and cellular leiomyoma is sometimes difficult and arbitrary.

OBJECTIVE

To correlate the clinicopathologic features of 12 well-differentiated sinonasal SMTs with MIB-1 index and clinical outcomes so as to better classify this group of tumors.

DESIGN

Twelve cases of sporadic well-differentiated SMTs arising from the sinonasal tract were retrieved from both institutions. High-grade leiomyosarcomas were excluded from this analysis. The histologic parameters assessed included circumscription, mucosal ulceration, cellularity, nuclear atypia, mitotic count, necrosis, and destruction of adjacent bony structures. The histologic classification of these tumors was based on the guidelines for SMTs of deep soft tissues, using greater than 4 mitotic figures (MF)/10 high-power fields (HPF) to separate SMTUMP from leiomyosarcoma and the presence of 1 to 4 MF/10 HPF to distinguish between leiomyoma and SMTUMP. Immunostaining of MIB-1 index was performed in 7 cases with available material.

RESULTS

This study showed a 1:1.5 male-female ratio and a mean age of 40 years (range, 20-67 years). The most frequent symptoms were nasal stuffiness and/or epistaxis. The tumors involved nasal cavity in 8 cases (67%), paranasal sinus alone in 2 cases (16.5%), and both nasal cavity and paranasal sinuses in 2 cases (16.5%). The tumors ranged in size from 0.3 to 5.5 cm (mean, 2 cm) and were classified as follows: 7 leiomyomas, 2 SMTUMPs, and 3 low-grade leiomyosarcomas. All 7 leiomyomas, 1 SMTUMP, and 1 leiomyosarcoma originated from vessel walls. Bone involvement was seen in both the SMTUMPs (1 of 2) and leiomyosarcomas (2 of 3). Focal infiltrative growth was observed only in the 3 leiomyosarcomas, 1 of which also showed microscopic coagulative tumor necrosis. Mitotic figures ranged from 0 to 10 (mean, 2.3), with absence of mitosis in all 7 leiomyomas, 1 to 4 MF/10 HPF in the 2 SMTUMPs, and more than 4 MF/10 HPF in the 3 low-grade leiomyosarcomas. The MIB-1 index was low (<or=5%) in both leiomyoma and SMTUMP groups, while the leiomyosarcomas showed a higher (>or=15%) proliferative index. All 12 patients were treated by surgical excision, and only 1 patient with leiomyosarcoma received postoperative radiation. In all 12 tumors, there was neither local recurrence nor distant metastasis after an average of 93 months of follow-up (range, 4-221 months).

CONCLUSION

Well-differentiated sinonasal SMTs are rare and occur in adults with a slight female predilection. The lesions confined within the nasal cavity were more common than those involving a single paranasal sinus or both nasal cavity and paranasal sinuses. Despite variations in location, clinical manifestation, histologic features, and MIB-1 index, these tumors appear to follow a favorable course. Complete surgical excision appears to provide adequate treatment for these patients.

Pathologic features of uteri and leiomyomas following uterine artery embolization for leiomyomas

The objectives of this study were to identify the presence/absence and location of any embolic material and to describe the morphologic appearance of the leiomyoma and adjacent tissues of cases undergoing surgical intervention following uterine artery embolization (UAE) for leiomyomas. A total of 555 women underwent UAE using polyvinyl alcohol particles (PVA) in a multicenter clinical trial. The histopathologic slides from 17 of 18 women who subsequently underwent myomectomy or hysterectomy in the follow-up period (median 8.2 months) were reviewed without knowledge of the indication for surgery or time elapsed since UAE. The presence/absence and distribution of PVA emboli, associated inflammatory response, and necrosis were noted. Necrosis of leiomyoma(s) was classified as hyaline-type, coagulative tumor cell necrosis, and/or acute suppurative necrosis. In all cases PVA emboli were identified within smooth muscle tumors of the uterine body, its periphery, cervix, uterine body, myometrium, and/or the adnexa. A florid foreign body giant cell type of chronic inflammatory reaction was seen within 1 week of UAE and persisted with visible PVA for up to 14 months post-UAE. Typically, post-UAE leiomyomas showed hyaline-type, but rarely coagulative tumor cell necrosis and acute suppurative necrosis could be seen as well. Five of eight cases coming to surgery for complications showed necrotizing endomyometritis with tissue infarction. PVA particles are recognizable in post-UAE specimens. Leiomyoma necrosis is typically of the hyaline type; coagulative tumor cell necrosis was rarely seen. In some cases with complications, uterine and/or cervical necrosis occurred. The applicability of these findings for UAE patients who have been successfully treated and not resected is uncertain.