Uterine myxoid leiomyosarcoma within a leiomyoma

Rate of Leiomyosarcomas during Surgery for Uterine Fibroids: 8-Year Experience of a Single Center

The aim of this study is to investigate the prevalence of occult malignant mesenchymal tumors in patients operated on for uterine fibroids in relation to the surgical approach and type of operation. A retrospective review of all patients that underwent surgery for uterine fibroids (January 2011-December 2018) at the 1st Department of Obstetrics & Gynecology at "Papageorgiou" Hospital. The surgical approach and clinicopathological characteristics were analyzed. A total of 803 patients were operated on: 603 (75.1%) with laparotomy, 187 (23.3%) laparoscopically, and 13 (1.6%) vaginally. Furthermore, 423 (52.7%) patients underwent hysterectomy and 380 (47.3%) myomectomies. Laparoscopy and myomectomy were offered to younger patients with fewer smaller uterine fibroids and were associated with statistically significant shorter hospitalization. The pathological reports revealed: 690 (86%) benign leiomyomas, 32 (4%) cellular leiomyomas, 29 (3.6%) degenerated leiomyomas, 22 (2.7%) adenomyomas, 18 (2.2%) atypical-bizarre leiomyomas, 1 (0.1%) STUMP, 5 (0.65%) endometrial stromal sarcomas, and 6 (0.75%) cases of leiomyosarcomas (LMS). All LMS were preoperatively characterized as suspicious and underwent abdominal hysterectomy. Morcellation was offered in two cases of atypical leiomyomas, with no morcellation-associated complication. Laparoscopy as a valuable surgical approach for young patients with fewer in number and smaller in size fibroids is associated with shorter hospitalization. The risk of unintended morcellation of LMS seems to be very low and can be reduced with careful preoperative work-up but not eliminated.

A Rare Case of Uterine Myxoid Leiomyosarcoma

A 49-year-old female patient was referred to a tertiary care hospital with a history of postmenopausal bleeding and abdominal pain that had persisted for the last two months. An abdominal examination revealed a huge mass that had been present for 12 weeks. A fibroid uterus was suggested by USG. A biopsy was done and sent to histopathology which revealed myxoid leiomyoma. Subsequently, the patient underwent total abdominal hysterectomy without bilateral salpingo-oophorectomy. Histopathological examination confirmed the diagnosis of myxoid leiomyosarcoma (MLMS) of the uterus.

"Unicorn in a Field of Horses": A Rare Case of Carcinosarcomatous Transformation in a Uterine Leiomyoma

Malignant transformation in leiomyoma is rare, with a few documented cases of sarcomatous transformation in leiomyomas. However, carcinosarcomatous transformation in leiomyomas is extremely infrequent. A 45-year-old female presented with a mass sensation per abdomen for the last five months. An abdominal ultrasound revealed multiple uterine fibroids. Contrast-enhanced magnetic resonance imaging revealed a large multiloculated abdominopelvic mass arising from the fundus of the uterus, along with multiple smaller subserosal fibroids. A total abdominal hysterectomy with bilateral salpingectomy was performed. Grossly, the uterus was bosselated with multiple subserosal fibroids. The larger degenerated fibroid showed a smooth outer surface; however, the cut surface was predominantly cystic and filled with necrotic material. Microscopically and immunohistochemically, the larger mass showed a high-grade biphasic tumor comprising carcinomatous and sarcomatous components with the peripheral solid areas showing compressed smooth muscle bundles representing the residual leiomyomatous areas. A final diagnosis of carcinosarcomatous transformation in leiomyoma was rendered. The index report highlights the significance of systematic gross and microscopic examination of all the uterine masses in patients with multiple leiomyomata.

Myometrial myxoidosis in a patient with systemic lupus erythematosus

Myometrium myxoidosis is new terminology to describe a non-neo-plastic process of extracellular mucinous accumulation in the myometrium wall of the uterus. We report a rare association of myometrial myxoidosis with lupus erythematosus in a 35-year old woman with a history of leiomyoma. At presentation, this case was diagnosed as a pelvic abscess and treated with specific antibiotherapy, and then discharged after clinical improvement. One week later, after recurrence of the symptoms, the patient underwent hysterectomy with bilateral salpingo-oophorectomy and appendectomy with anterior abdominal soft tissue part resection. Pathological analysis revealed diffuse hypo-cellular myxoid areas intersecting the smooth muscle layer of the uterus and cervix in addition to a focal area in the interstitium of smooth muscles of the appendix and soft tissue of the anterior abdominal wall. This case emphasizes the importance of distinguishing between myxoid neoplastic and non-neoplastic lesions with myxoid changes. SIMILAR CASES PUBLISHED: To our knowledge, there are only two similar cases reported.

Molecular Pathology: Predictive, Prognostic, and Diagnostic Markers in Uterine Tumors

This article focuses on the diagnostic, prognostic, and predictive molecular biomarkers in uterine malignancies, in the context of morphologic diagnoses. The histologic classification of endometrial carcinomas is reviewed first, followed by the description and molecular classification of endometrial epithelial malignancies in the context of histologic classification. Taken together, the molecular and histologic classifications help clinicians to approach troublesome areas encountered in clinical practice and evaluate the utility of molecular alterations in the diagnosis and subclassification of endometrial carcinomas. Putative prognostic markers are reviewed. The use of molecular alterations and surrogate immunohistochemistry as prognostic and predictive markers is also discussed.

MED12 mutations in leiomyosarcoma and extrauterine leiomyoma

Leiomyoma and leiomyosarcoma share morphological features and smooth muscle differentiation, and both arise most frequently within the uterine corpus of middle-aged women. However, they are considered biologically unrelated tumors due to their disparate clinical, cytogenetic, and molecular features. MED12, the mediator complex subunit 12 gene, has been recently implicated as an oncogene in as many as 70% of sporadic uterine leiomyoma. In the present study, we show MED12 hotspot exon 2 mutations in extrauterine leiomyoma (3 of 19 cases) and in leiomyosarcoma (3 of 13 uterine cases). We also show that MED12 mutations are found in both primary and metastatic leiomyosarcoma. Immunoblotting studies demonstrated MED12 protein expression in 100% of leiomyomas (13) and leiomyosarcomas (20), irrespective of MED12 exon 2 mutation status or histological grade. These findings indicate that MED12 has oncogenic roles in a broad range of smooth muscle neoplasia, including tumors arising in extrauterine locations.

MED12 alterations in both human benign and malignant uterine soft tissue tumors

The relationship between benign uterine leiomyomas and their malignant counterparts, i.e. leiomyosarcomas and smooth muscle tumors of uncertain malignant potential (STUMP), is still poorly understood. The idea that a leiomyosarcoma could derive from a leiomyoma is still controversial. Recently MED12 mutations have been reported in uterine leiomyomas. In this study we asked whether such mutations could also be involved in leiomyosarcomas and STUMP oncogenesis. For this purpose we examined 33 uterine mesenchymal tumors by sequencing the hot-spot mutation region of MED12. We determined that MED12 is altered in 66.6% of typical leiomyomas as previously reported but also in 11% of STUMP and 20% of leiomyosarcomas. The mutated allele is predominantly expressed in leiomyomas and STUMP. Interestingly all classical leiomyomas exhibit MED12 protein expression while 40% of atypical leiomyomas, 50% of STUMP and 80% of leiomyosarcomas (among them the two mutated ones) do not express MED12. All these tumors without protein expression exhibit complex genomic profiles. No mutations and no expression loss were identified in an additional series of 38 non-uterine leiomyosarcomas. MED12 mutations are not exclusive to leiomyomas but seem to be specific to uterine malignancies. A previous study has suggested that MED12 mutations in leiomyomas could lead to Wnt/β-catenin pathway activation however our immunohistochemistry results show that there is no association between MED12 status and β-catenin nuclear/cytoplasmic localization. Collectively, our results show that subgroups of benign and malignant tumors share a common genetics. We propose here that MED12 alterations could be implicated in the development of smooth muscle tumor and that its expression could be inhibited in malignant tumors.

Carcinosarcoma arising in a uterine leiomyoma: report of a unique neoplasm

Malignant transformation of a uterine leiomyoma is an exceedingly rare phenomenon. Previous reported examples of malignant neoplasms to arise so include leiomyosarcoma, angiosarcoma, and malignant mesenchymoma. We report an intramural carcinosarcoma arising in a uterine leiomyoma in a 38-year-old woman. This case is unique in being the first recorded carcinosarcoma arising within a uterine leiomyoma and the first example of an epithelial neoplasm to do so. We discuss the differential diagnosis and possible pathogenesis of the tumor that has likely arisen secondary to epitheliogenesis in a mesenchymal neoplasm.

Uterine leiomyosarcoma arising in leiomyoma: clinicopathological study of four cases and literature review

In this study we examined four cases of leiomyosarcoma (LMS) arising in leiomyoma (LM). The patients ranged from 40 to 64 years old. Symptoms were unspecific and preoperative diagnosis of LMS had not been made. Size of the tumors ranged from 4 cm to 20.5 cm. All patients were in stage I and no patients developed recurrent disease. Histologically, the LMS component showed moderate to severe cytological atypia and an increased mitotic count in all cases. Tumor cell necrosis in the LMS was seen in three cases. Associated LM component was cellular in one case. The LMS component showed p53 expression in three of four cases and p16 expression was seen in two cases. The LM component lacked p53 expression in all cases and demonstrated p16 expression in two cases, including one case of cellular LM. In all cases, Ki-67-positive cells were less than 5% in the LM component and more than 25-30% in the LMS component. This study reveals that: (i) malignant transformation can occur even in relatively small LM; (ii) patients with LMS with an LM component have a favorable prognosis; and (iii) immunohistochemical examination of p53, p16 and Ki-67 is useful for identification of malignant focus.

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.

A myxoid liposarcoma arising in a leiomyoma of the uterus: a case report

BACKGROUND

A liposarcoma is the most frequent soft tissue sarcoma found in adults, however, a liposarcoma arising in uterus is extremely rare. Indeed, a liposarcoma coexistent with a leiomyoma is even rarer and there is only one case has been reported in the English literature to date.

CASE

We describe a case of the uterine liposarcoma arising in a leiomyoma in 48-year-old woman who presented with dysmenorrhea, brownish vaginal discharge, and a rapidly enlarging lower abdominal mass. The tumor emerged from the lower segment of the endometrium and filled the endometrial cavity as a polypoid lesion. The authors of this study documented the adipocyte origin of the tumor with immunohistochemical and electron microscopical studies, the available literature was reviewed and the possible histogenesis was discussed.

CONCLUSION

We herein report a case of very rare primary liposarcoma arising in a submucosal uterine leiomyoma.

Areas with benign morphologic and immunohistochemical features are associated with some uterine leiomyosarcomas

The pathogenesis of uterine leiomyosarcomas (LMS) is poorly understood. It is unknown if these tumors arise de-novo or from pre-existing leiomyomata (LM) or atypical leiomyomata. In this study, we evaluated morphologic heterogeneity within uterine LMS to identify possible precursor lesions. We reviewed 11 cases of total hysterectomy in which the final diagnosis was LMS. All slides from the grossly recognized tumor were evaluated for the degree of atypia and mitotic counts within the leiomyosarcomas. The slides with the lowest and highest mitotic count were stained with monoclonal antibody to p53, MIB-1 and ER/PR. The number of cells stained was subjectively assessed to nearest 5%, with 1% for rare positive cells. Morphologically benign tumor areas were identified in 5 of the 11 tumors. These areas showed <5 mitoses/10 HPF, with 1+ atypia in 4 cases and 1-2+ atypia in 1 case. No necrosis was seen by definition. Immunostains could be done in 4 of these 5 cases. These morphologically benign areas showed a p53 expression of 1% in each of the 4 cases, with low MIB-1 (5 to 15%) and high ER/PR expression (ER: 50-100%, PR: 10-100%). Morphologically malignant areas had 13 to 31 mitoses/10 HPF, 2+ to 3+ atypia, p53 expression of 70% to 100%, MIB-1 expression of 40% to 100%, ER expression of 1 to 100% and PR expression of 1 to 100%. The benign and malignant areas merged in all cases. Morphologic and immunohistochemical spectrum of changes from benign to malignant is seen in 50% of LMS. This raises the possibility of progression of some leiomyomata to LMS.

Massive myxoid leiomyosarcoma of the uterus

Uterine myxoid leiomyosarcoma is a very rare and aggressive variant of uterine sarcoma, of which only 26 cases have been described in the literature published in English. A 59-year-old woman, who had been menopausal for 5 years and had a huge abdominal mass underwent laparotomy; histopathology of the bulky tumor revealed the particular characteristics of a myxoid leiomyosarcoma. Immunohistochemically, Ki-67 contributed toward indicating a malignancy, whereas p53 and progesterone and estrogen receptors were negative. The level of serum Ca125 was high at diagnosis, within normal limits after the fifth cycle of chemotherapy, and subsequently increased again at recurrence. Sixteen months after surgery, the patient died of respiratory failure. Immunohistochemistry and Ca125 levels can aid the diagnosis, management, and prognosis of uterine myxoid leiomyosarcoma.

Myxoid endometrial stromal sarcoma of the uterus

A rare case of a myxoid type of endometrial stromal sarcoma of the uterus in a 41-year-old woman is reported. A tumor was found in the myometrium and was well circumscribed, measuring 9 x 7 x 7 cm in size. The tumor was mainly composed of a hypocellular area with tumor cells separated by prominent myxoid stroma. The tumor cells were spindle-shaped and resembled endometrial stromal cells. Numerous small thin-walled vessels were seen throughout the tumor. Immunohistochemically, the tumor cells were diffusely stained for estrogen and progesterone receptors and CD10, and focally and weakly for HHF35, alpha-smooth muscle actin and desmin, but not stained for h-caldesmon. These results indicated that the tumor originated from endometrial stromal cells. The tumor had an increased mitotic activity (MIB-1 labeling index: 1-10%), and focally showed nuclear pleomorphism. Thus, this tumor had a malignant potential and was diagnosed as a myxoid type of low-grade endometrial stromal sarcoma. The patient is currently well with no evidence of local recurrence or metastasis 21 months after the operation. This case indicates a wide morphological spectrum of endometrial stromal tumor. A myxoid endometrial stromal sarcoma should be considered in the different diagnosis of the intramural myxoid tumors in the uterus.

Myxoid leiomyosarcoma of the uterus with subsequent pregnancy and delivery

BACKGROUND

Myxoid leiomyosarcoma of the uterus is an extremely rare neoplasm. In young women with this disease, fertility should be considered in the treatment protocol.

CASE

A 20-year-old woman presented with a huge pelvic mass originating from the uterine wall and showing a histopathology of myxoid leiomyosarcoma. Five and one-half years after laparotomy, the recurrent tumor was found and removed. Two years after the second operation, she became pregnant, and delivered a healthy baby by cesarean section. Multiple recurrent masses were evident and removed at cesarean section. She is alive and well without evidence of recurrence 1 year after delivery.

CONCLUSION

The best treatment for this tumor is not established. In young women with a desire to bear children, the management is more controversial.

Malignant mesenchymoma of the uterus, arising in a leiomyoma

AIMS

To document and find evidence for the rare occurrence of malignant progression of a benign uterine leiomyoma with divergent mesenchymal differentiation. In a 54-year-old female a large pedunculated tumour was encountered which had suddenly increased in size and had apparently arisen at the site of a subserosal uterine leiomyoma first described 19 years earlier. The tumour seemed histologically diverse in its composition. The possibility of malignant progression of the benign leiomyoma with divergent mesenchymal differentiation was entertained.

METHODS AND RESULTS

In the resected tumour, smooth muscle, osseous and adipose components were identified and these were assessed using recognized histological criteria of malignancy. In addition to a benign smooth muscle component, malignant leiomyosarcomatous tissue was seen in addition to a malignant osseous component and a malignant adipose component. The tumour thus met the criteria of a malignant mesenchymoma. The relationship of the different components of the tumour was analysed by immunohistochemistry and with molecular loss of heterozygosity (LOH) analysis. In the osseous and leiomyosarcomatous components a similar LOH pattern was observed. The adipose component showed a distinct LOH pattern. Retention of smooth muscle differentiation in the osseous component was demonstrated by desmin immunostaining.

CONCLUSION

Malignant transformation of benign uterine leiomyoma may rarely occur. Mesenchymal stem cells underlying these tumours may show divergent mesenchymal differentiation.

Myxoid leiomyosarcoma of the uterus

A 70-year-old, menopausal Japanese woman with large uterine tumor underwent total hysterectomy. Microscopic examination revealed a myxoid leiomyosarcoma with 5 to 6 mitoses/10 high power field (HPF). Immunohistochemically, the tumor cells reacted with desmin, suggesting that they are derived from uterine smooth muscle cells. The patient was treated with the combination chemotherapy consisting of cisplatin, adriamycin and cyclophosphamide, and she has been free from disease for 70 months after the operation.