Primary Leiomyosarcoma Of Bone Research Articles

What Is the Impact of Multimodal Treatment in Patients with Leiomyosarcoma of Bone? A Multicenter Study of 35 Patients with an Ultra-Rare Tumor Entity.

Primary leiomyosarcoma of bone (LMSoB) is extremely rare, comprising only <0.7% of primary malignant bone tumors, and is therefore considered an ultra-rare tumor entity. There is currently no consensus as to whether therapeutic strategies should be based on the biological characteristics of soft tissue leiomyosarcoma or on primary tumor localization in the bone. The use of perioperative chemotherapy and its effectiveness in this rare tumor entity remains unclear. We aimed to evaluate the impact of different treatment approaches in a multicenter setting with a total of 35 patients included. The 5-year overall survival (OS) was 74%. Patients with localized disease undergoing surgery had a significantly higher 5-year OS compared to patients who did not undergo surgical treatment (82% vs. 0%, p = 0.0015). Axial tumor localization was associated with worse event-free survival (EFS) probability (p < 0.001) and OS (p = 0.0082). A high proportion of our patients developed secondary metastases. Furthermore, the perioperative chemotherapy protocols applied to our patients were not associated with an improved EFS or OS. Therefore, the benefit of perioperative chemotherapy in LMSoB needs to be further investigated, and the choice of agents still needs to be clarified.

Rare Case of Primary Leiomyosarcoma of Bone – Findings on 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

Primary leiomyosarcoma of bone (PLB) is a rare tumor, constituting &lt;0.7% of all primary bone malignancies. It is clinically aggressive with heterogeneous presentation and a dismal prognosis. The most common presentation is pain with swelling and pathological fracture at times. Limited literature is available on PLB and only about 150 cases have been reported to date with only a few case reports defining the utility of 18F-fluorodeoxyglucose (18-F FDG) positron emission tomography/computed tomography (PET-CT) in its management. We hereby present a case of primary leiomyosarcoma of the right distal femur and the role of FDG-PET-CT in its management.

A Case Study of Primary Leiomyosarcoma of Bone with Duodenal Hemorrhage

&lt;p&gt;臨床上常見因長期使用非類固醇類消炎藥（non-steroidal anti-inflammatory drug, NSAID），造成上腹痛合併解黑便及頭暈症狀而至胃腸內科求治病患。本案例為62歲男性，近日因上腹悶痛合併頭暈持續3天故來院求治，初步臆斷為十二指腸糜爛性潰瘍併出血收治住院治療。身體評估發現右橈骨異常腫塊，詢問病史發現個案長期藉由服用NSAIDs緩解右前臂腫脹痠痛症狀，安排右手X光檢查及會診骨科進行右橈骨病灶處切片。十二指腸及右橈骨病灶處切片病理報告呈現相同異常梭形細胞，最終確診右橈骨骨源性平滑肌肉瘤（primary leiomyosarcoma of bone, LMSB）併十二指腸轉移。經跨團隊及院際醫療討論後，個案轉至醫學中心接受術前放射線、手術及化學藥物等治療。透過本案例探討，提醒入院時詳細完整病史詢問及身體評估有助於鑑別診斷，並可提供臨床更多元之考量，避免錯失治療黃金時間。&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;Patients who have been taking non-steroidal anti-inflammatory drugs (NSAIDs) for a long time are of-ten referred to the gastrointestinal clinics due to epigastric pain combined with melena and dizziness symptoms. The case in this study is a 62-year-old man who had epigastric pain and dizziness for three days. The initial diagnosis was duodenal erosive ulcer and hemorrhage, and the patient was admitted to hospital for treatments. The physical assessment revealed an abnormal mass in the right radius, and a medical history was found that NSAIDs were taken by the patient for a long period to relieve the swelling and soreness of the right forearm. An X-ray examination of the right hand was subsequently arranged and a consultation with the orthopaedic specialists was conducted for further conduct biopsy. The pathological report of the duodenum and right radius lesions showed the same abnormal spindle cells, therefore, the primary leiomyosarcoma of bone (LMSB) in right radius with duodenal metas-tasis was finally confirmed. Through multidisciplinary and inter-hospital medical discussions, the patient was immediately transferred to the medical center for preoperative radiotherapy followed by surgery and chemotherapy. This case study indicates the importance of performing a detailed medical history examination and physical assessment upon admission which are helpful for differential diag-nosis and can provide more clinical considerations for promptly treatments.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Primary Osseous Leiomyosarcoma with Vertebral and Nodal Metastasis in a Young Woman: A Rare Case Report.

Introduction. Primary leiomyosarcoma of bone is rarely described in the literature. In young patients, the clinical and radiological features may mimic relatively common tumours like osteosarcoma. Vertebral and nodal metastasis from osseous leiomyosarcoma is extremely uncommon. Case presentation. A 25-year-old female presented with progressively increasing pain and swelling of the right knee. Clinical and radiological features were suggestive of osteosarcoma. Pre-operative biopsy showed a malignant spindle cell tumour. The surgical resection specimen showed features of leiomyosarcoma of the right proximal tibia. On further evaluation, the patient was found to have an L3-L4 vertebral lesion and histopathological evaluation showed a similar tumour. After 11 months of initial presentation, the patient had axillary lymph node metastasis. Conclusion. Primary osseous leiomyosarcoma should be considered as a differential diagnosis even in young patients presenting with meta-diaphyseal expansile malignant bony lesions. Histology and ancillary studies can confirm the diagnosis.

Comparison of clinicopathological features and outcomes in patients with primary leiomyosarcoma of bone and soft tissue.

e23526 Background: Leiomyosarcoma is a rare malignancy that may occur in bone. This investigation described the characteristics and outcomes of primary leiomyosarcoma of bone (PLB) compared to soft tissue leiomyosarcoma (SLMS). Methods: This study was a retrospective review using the Surveillance, Epidemiology, and End Results (SEER) database from 1975 to 2016. Continuous and categorial variables were described, and Cox regression were used to identify factors of prognostic significance. Results: Seven thousand five-hundred two patients met inclusion criteria. Seventy-four (1%) were PLB and 7428 (99%) were SLMS. On multivariable analysis for high-grade SLMS radiation (neoadjuvant: HR, 0.56; 95% CI, 0.4-0.8; p = 0.003, and adjuvant: HR, 0.75; 95% CI, 0.6-0.9; p = 0.008) and surgery (procedure specific) improved DSS, while age (HR, 1.013; 95% CI, 1.0-1.1; p &lt; 0.001), tumor size greater than or equal to 5 cm (HR, 3.16; 95% CI, 2.3-4.2; p &lt; 0.001), abdomen/pelvis/trunk/thorax tumors (HR, 1.31; 95% CI, 1.1-1.6; p = 0.006), and distant metastases at presentation (HR, 2.6; 95% CI, 2.1-3.3; p &lt; 0.001) negatively influenced DSS. Conclusions: Radiation and surgery positively influence survival in high-grade SLMS while chemotherapy appears to have no benefit. Surgery alone appears to lower the mortality risk in PLB.

Primary leiomyosarcoma of femur: A rare entitycase report and review of literature

Background: We report this case to highlight clinical and pathological features of this rare entity. Methods: It is about a 48 year-old woman with an osteolytic lesion of the lower extremity of the left femur. Result: A biopsy of the lesion showed densely cellular malignant mesenchymal proliferation. It was made by bundles of smooth muscle cells with nuclei of moderate to severe atypia. The immunohistochemical study showed an intense and diffuse cytoplasmic positivity of tumor cells with the smooth anti-muscle. Desmin was focal positive. After neoadjuvant chemotherapie, a knee block resection was made. Macroscopically, it was a 10 cm sized tumor located in the distal part of tumor. Histologically tumor showed post chemotherapy effects estimated at 20%. The bone and muscle surgical limits were unscathed. Conclusion: Primary leiomyosarcoma of bone is a rare and a diagnostically challenging tumor entity.

Primary Leiomyosarcoma of Humerus Presenting with Pathological Fracture and Treated Initially with Inadvertent Plate Fixation: a Case Report with Literature Review

Leiomyosarcoma is a malignant tumor of smooth muscle origin and commonly diagnosed in the uterus, gastrointestinal tract, and mucous membranes or as metastasis to the skeletal system. Primary leiomyosarcoma of bone is an uncommon type of tumor. Patient with primary bone sarcoma may present with a pathological fracture following a trivial injury, resulting in pain, swelling, and deformity. The pathological fracture needs to be evaluated with a high index of suspicion and proper investigations must be performed prior to fracture fixation. We present a case of primary leiomyosarcoma of humerus, who presented as pathological fracture and underwent inadvertent plating at a peripheral hospital. We treated this patient with wide resection of the tumor and the reconstruction was performed with an implant (Kuntscher’s nail and extra-articular plate) with bone cement spacer. The use of this novel method allowed us to perform implant fixation with small distal humerus bone segment and preserve native elbow joint. In this case report, we aim to highlight the importance of thorough preoperative evaluation and keeping a high index of suspicion while dealing with suspected pathological fractures to differentiate between primary and metastatic disease.

Primary Leiomyosarcoma of Bone: Review and Update.

Leiomyosarcoma of bone is a rare primary osseous sarcoma characterized by smooth muscle differentiation and absence of malignant osteoid formation. Leiomyosarcoma of bone is diagnostically challenging; this can be improved with greater awareness of this entity and the ability to differentiate it from its histologic mimics. Because of its rarity, only a small number of studies are available in the literature. These factors contribute to our limited understanding of its pathology, prognosis, and treatment. To review the clinicopathologic features of leiomyosarcoma of bone and present the most up-to-date understanding of its behavior and management in accordance with the current literature. Review of pertinent literature on the major features, current knowledge thereof, and the authors' experience in the diagnosis and management of leiomyosarcoma of bone. Leiomyosarcoma of bone is a rare but well-recognized primary osseous sarcoma that may arise de novo or in association with radiation. Although it is diagnostically challenging, awareness of this rare sarcoma and knowledge of its key histomorphologic and immunohistochemical features allow for accurate diagnosis.

Primary leiomyosarcoma of bone: imaging findings

Objective To analyze the radiological imagines and SPECT imaging features of primary leiomyosarcoma of bone and to improve the diagnostic level. Methods The imaging data of 16 patients in our hospital from January 2009 to May 2018 were retrospectively analyzed by two senior musculoskeletal radiologists, and they were all proved by surgery and pathology. The location of the lesions, type of bone destruction, size, soft tissue mass, mineralization, pathological fracture and periosteal reaction were detected by radiography and CT. The types of bone destruction are osteolytic, cystic and mixed. Periosteal reaction was divided into codman triangle, layered periosteal reaction and spiculate periosteal reaction. The signal intensity of lesions, size, distruction of the bony cortex, soft tissue mass and peritumoral edema were detected by MRI.Signal intensity was divided into low signal,iso-signal and high signal by taking surrounding normal muscles as reference. Enhancement scan was used to detect the form of enhancement. SPECT bone scan: compared with normal bone, SPECT bone scan signals were higher than normal bone, which was called concentrated radioactivity. Results Among the 16 cases, located in tibia(5 cases), femur (4 cases), sacrum(1 case), pubis(1 case), ilium(1 case), thoracic vertebra (2 cases) and humerus(2 cases). Radiography showed osteolytic, cystic and mixed bone destruction, among which 8 cases were osteolytic, 2 cases were cystic, 4 cases were mixed, and 1 case was normal. On CT images, 9 cases were osteolytic, 6 cases with soft tissue masses, among which 3 cases with partial sclerosis rim (2 cases with pathological fractare and obviously enhanced), 1 case with mild bone expansion and soft tissue, 2 cases with partial sclerosis rim. Four cases were mixed, all with cortical bone destruction, penetration, 1 case with soft tissue mass and periosteal reaction, 1 case which in the long bone of the extremity was central in location with periosteal reaction. Two cases were obviously and heterogeneously enhanced atter the enhanced CT scanning (1 case with bone expansion). Two cases were cystic,all with cortical destruction and penetration,1 case with soft tissue mass,1 case with partial sclerotic rim;after the enhanced CT scanning,2 case were obviously and heterogeneously enhanced. The most of the MR imagines showed the iso-intensity signal (10cases) and/or lightly lower signal (3cases), lightly higher sign (2cases) on T1WI, inhomogeneous hyperintensity on T2WI (15cases),after injected contrast medium,the tumor was inhomogeneous enhancement (14cases) with the cysts, necrosis and hemorrhage in it,11 cases with soft tissue masses,12 cases accompanied by peritumoral edema. On SPECT bone scan, 10 Cases showed significant concentrated radioactivity(1 case was circumferential) and 1 case was mild concentrated radioactivity. Conclusion PLB usually occurs in the lower extremities,more frequently at the distal end of the femur, the proximal end of the tibia. The mainly appearance are central situated and osteolytic destruction with mass of the soft tissue. Although PLB has some imaging features, it is difficult to differentiate it from malignant bone tumors. Multi-imaging modalities such as radiography, CT, MRI and SPECT may suggest the diagnosis. Key words: Leimyosarcoma; Bone; Magnetic resonance imaging; Tomography, X-Ray computed

Successful generation of patient-derived xenografts and cell lines as preclinical models for sarcomas.

e22549 Background: The establishment of patient-derived preclinical models has been a challenge issue in sarcomas, because of the rarity of diseases. We report our successful experience in establishing patient-derived sarcoma xenografts and cell lines. Methods: Tumor tissue samples from sarcoma patients undergoing surgery were collected by a team of orthopedicians and pathologists. Small tumor fragments were subcutaneously transplanted to immunodeficient NOG mice. The other part was used to establish a cell line using serum-containing media. The omics profiling was performed to examine the preservation of molecular backgrounds during the model establishment. Effects of FDA-approved drugs were examined in the established models. Results: Since April 2014, tumor samples from 246 sarcoma cases have been processed. The sample characteristics are summarized in the table. Currently we have established PDXs and cell lines from 39 and 27 cases, respectively. Xenografts and cell lines were established from unique sarcomas such as CIC-DUX4 fusion positive sarcoma, extraskeletal osteosarcoma, primary leiomyosarcoma of bone, and alveolar soft part sarcoma. A take rate of xenografts and cell lines varied among the sarcoma types. Omics profiles considerably changed during the process of model establishment. Anti-cancer drugs with significant tumor suppressive effects were detected. Conclusions: Our patient-derived cancer models will facilitate translational sarcoma research. The original biological features preserved in the xenografts and cell lines should be clarified to optimize the utility of sarcoma models. Currently, our cell lines are available for the academic researchers upon a request.

PRIMARY LEIOMYOSARCOMA OF BONE: CLINICOPATHOLOGIC AND PROGNOSTIC FACTORS ANALYSIS IN A SINGLE INSTITUTION.

ABSTRACTObjective:Primary leiomyosarcoma of bone (PLB) is a rare type of malignant bone tumor considered as a variant of the spindle cell sarcomas (SCS). The objective of this study was to analyze the clinicopathologic and the prognostic factors of patients with PLB treated at a single institution.Methods:We retrospectively reviewed the records of 22 patients with pathologically confirmed PLB. The data collected were: age, sex, tumor size and location, grade and stage of the disease and histopathologic features. Mean age was 45.5 years (range, 17 to 73 y). Location was: upper limb (27.3%), lower limb (68.2%) and pelvis (4.5%). Patients had high grade in 90.9% of the reports. Margins were negative in 77.3% of the cases. Histological reports describe spindly sarcomatous cells arranged in fascicles with increased vascular formation without osteoid or chondroid matrix production. On immunohistochemistry, smooth muscle actin and desmin where positive in all cases.Results:Mean follow-up time was 73.5 months (range, 5.3 to 331.1 m). We found 22.7% of local recurrence (LR). Distant metastasis (DM) was reported in 9 (40.9%) patients. Lung metastasis was the only DM affected site. Overall survival (OS) rate in 5 years was 59.1%. Predictors of OS were LR and DM.Conclusions:PLB is an extremely rare malignant bone tumor that has a higher rate of DM and similar OS prognosis compared with other bone sarcomas. Level of Evidence IV, Case Series.

Establishment and characterization of patient-derived xenograft and its cell line of primary leiomyosarcoma of bone.

Primary leiomyosarcoma (LMS) of bone is a rare and aggressive mesenchymal malignancy that differentiates toward smooth muscle. Complete resection is the only curable treatment, and novel therapeutic approaches for primary LMS of bone have long been desired. Patient-derived xenografts (PDXs) and cell lines are invaluable tools for preclinical studies. Here, we established PDXs from a patient with primary LMS of bone and a cell line from an established PDX. Bone primary LMS tissue was subcutaneously implanted into highly immune-deficient mice. After two passages, a piece of the tumor was subjected to tissue culturing, and a morphological evaluation and proteomic analysis were performed on the PDX and the established cell line. Moreover, the responses of the established cell line to anti-cancer drugs were examined. Microscopic observations revealed that the PDX tumors retained their original histology. The cell line was established from the third-generation PDX and named NCC-LMS1-X3-C1. The cells were maintained for over 18mo and 40 passages. The cells exhibited a spindle shape and aggressive growth. Mass spectrometric protein identification revealed that the original tumor tissue, PDX tumor tissue, and NCC-LMS1-X3-C1 cells had similar but distinct protein expression profiles. We previously established the cell line, NCC-LMS1-C1, from the tumor tissue of same patient. We found that the response to drug treatments was different between NCC-LMS1-X3-C1 and NCC-LMS1-C1, suggesting the heterogeneous traits of tumor cells in the identical tumor tissue. This set of PDXs and stable cell line will be a useful resource for bone LMS research.

Primary Leiomyosarcoma of Bone: A Case Report

: Leiomyosarcoma is an aggressive type of soft tissue neoplasm that originates from smooth muscle cells; it is typically found in the uterus, gastrointestinal tract, and retroperitoneum. Primary leiomyosarcoma of bone is an extremely rare phenomenon first reported in 1965. Here, we present a case of primary leiomyosarcoma of bone occurred in the proximal humerus of a 41-year-old man who was referred to our orthopaedic clinic with a chief complaint of persistent left shoulder pain. Radiological investigations revealed a proximal lesion of the left humerus with periosteal reaction. Core needle biopsy of the lesion was performed later, which pointed to primary leiomyosarcoma of bone as the underlying pathology. Subsequently, complete resection of the lesion and prosthetic replacement of the proximal humorous were performed. The patient was followed three months after the surgery, and no sign of local recurrence or metastatic lesion was detected. To the best of our knowledge, this is the first case report of primary leiomyosarcoma of bone in Iran.

Primary leiomyosarcoma of the first metatarsal bone: A case report

INTRODUCTION: Primary leiomyosarcoma of bone is a rare entity which has never been reported in the foot. We report a case of primary leiomyosarcoma of metatarsal bone. CASE REPORT: A 60-year-old male presented with a history of pain, progressively increasing swelling and a non-healing ulcer over the dorsomedial aspect of his right foot. Plain radiograph showed an osteolytic, destructive lesion of the first metatarsal with involvement of surrounding soft tissue and bones. Magnetic resonance imaging showed a lesion that was hypointense on T1- and heterogeneous on T2-weighted images. Histology of the tumour with immunohistochemistry features aid in making the diagnosis of primary leiomyosarcoma of the first metatarsal bone, which was rare for this location. DISCUSSION: A brief review of the literature is done to determine the epidemiology, radiological and histological features and management of this tumour. CONCLUSION: Primary leiomyosarcoma of bone is a rare tumour and should be kept in the differential diagnosis of primary malignant osteolytic, destructive neoplasms especially in the older age group LEVEL OF EVIDENCE: therapeutic, IV

Primary Leiomyosarcoma of Bone: Analysis of Prognosis

Leiomyosarcoma of bone is just one of the variants of spindle cell sarcoma of bone characterised by the expression of desmin and other markers indicating a significant element of smooth muscle in the tumour, without osteoid production we have investigated the management and outcome of this rare type of primary malignant bone tumour. Method. Retrospective review of data stored on a prospective database. Results. In a database of 3364 patients with primary malignant bone sarcomas, 31 patients were identified with a primary leiomyosarcoma of bone. There were 12 males and 19 females with a mean age of 46 and tumour size of 8 cm. The most common site was the distal femur followed by the proximal tibia. Treatment was with chemotherapy and surgical resection. Seven of the patients had metastases at diagnosis. Surgery was carried out in 28 patients, 8 having amputation and 20 limb salvage. Three patients developed local recurrence, but half developed metastases. All patient disease-specific survival was 57% at five years and 44% at 10 yrs but for those without metastases was 82% and 60%, respectively. The only prognostic factors were metastases at diagnosis. Conclusion. Leiomyosarcoma of bone is a very rare primary malignant bone tumour affecting a predominantly older population. Despite the high incidence of metastases, survival is better than for other bone sarcomas for those without metastases at diagnosis.

Primary leiomyosarcoma of bone—a clinicopathologic study of 8 uncommon cases with immunohistochemical analysis and clinical outcomes

Primary leiomyosarcoma of bone is a rare and a diagnostically challenging tumor entity. Over a 7-year period, we identified 8 such cases that fulfilled the diagnostic criteria in 6 men and 2 women, with age ranging from 25 to 59 years (mean, 42.7 years). All cases were noted in the lower limbs, including femur and tibia as the commonly involved bones in 4 and 3 cases, respectively. On radiography, the most consistent feature was a solitary osteolytic lesion with cortical destruction, unassociated with matrix formation. On histopathology, all cases showed spindly sarcomatous cells, mostly arranged in fascicles and whorls. Of 8 cases, 6 (75%) were of high grade. Prominent vasculature was noted in 5 cases. Two cases displayed focal mineralization, including calcification and heterotropic woven bone formation in 1 case each, but lacked malignant osteoid or chondroid matrix. One case showed osteoclast-like giant cells. On immunohistochemistry, smooth muscle actin was diffusely positive in all cases (100%), desmin was positive in 6 (75%) of 8 cases, and h-caldesmon was positive in 5 (83.3%) of 6 cases. Five cases underwent surgery, including 3 amputations and 2 wide excisions. One case underwent chemotherapy. On follow-up, 5 cases developed metastasis, including 1 case with another, who died within 17 and 5 months. Leiomyosarcoma of bone is uncommon and diagnostically challenging. An index of suspicion is necessary for this diagnosis, especially in cases of lytic, destructive bone lesions, unassociated with matrix production, that show spindly sarcomatous cells on histopathology. Immunohistochemical analysis, including an optimum panel formed by smooth muscle actin (diffuse positivity), desmin, and h-caldesmon, is necessary for substantiating this diagnosis. Surgery forms the treatment mainstay. The prognosis appears to be dismal.

Primary leiomyosarcoma of bone: a report on three patients

Primary leiomyosarcoma of bone is a rare aggressive tumor that occurs mainly in older people. It resembles other malignancies clinically and radiologically, and differential diagnosis is based on histopathology, including immunohistochemistry. If leiomyosarcoma is found in bone, the possibility that it is a metastasis from a distant tumor should be investigated. The treatment is surgical excision with wide margins. Here we present three patients who had primary leiomyosarcoma of radius, ilium, and femur, respectively, and who were treated surgically.

Coexistence of Two Rare Sarcomas: Primary Leiomyosarcoma of Bone and Epithelioid Hemangioendothelioma of the Liver

A 33-year-old woman sought medical attention for a painful swelling of the left ankle. Plain radiographs revealed an osteolytic lesion involving the left distal tibia. An excisional biopsy provided the diagnosis of leiomyosarcoma in the tibia. A staging work-up was performed and an abdominal CT showed 4 liver hypodense lesions in both lobes with peripheral contrast enhancement. A liver biopsy confirmed the diagnosis of epithelioid hemangioendothelioma of the liver. No association between these two entities has been described before. This case introduces the importance of the pathological confirmation of apparent metastatic lesions in low grade sarcomas and provides a review of the literature of both tumours.

A primary leiomyosarcoma of bone containing pseudoepithelial plexiform elements

A rare but distinctive variant of smooth muscle tumours that occurs almost exclusively in the uterus is characterised by the presence of plexiform tumourlets, which are composed of clumps and cords of tumour cells that form a discrete pseudoepithelial component. We report on a case of a primary leiomyosarcoma of the proximal humerus, which, in addition to characteristic histological and immunophenotypic features of leiomyosarcoma, contained plexiform tumourlets. Tumour cells in the plexiform component focally expressed muscle/smooth muscle actin, calponin and cytokeratin. Spindle-shaped and epithelioid smooth muscle tumour cells also expressed the above antigens. This is the first report of a plexiform smooth muscle tumour arising in bone. This case is remarkable, not only for being only the second reported case of a malignant plexiform smooth muscle tumour, but also for being one of very few examples of this type of tumour arising outside the uterus; it also is unique in having arisen in a male patient. This variant of primary leiomyosarcoma needs to be distinguished from other bone tumours containing epithelial elements, notably metastatic carcinoma.

Primary Leiomyosarcoma of Bone

Primary leiomyosarcoma of bone is a very rare tumor. Four cases are reported: 3 tumors were located in the femur and 1 in the talus. Clinical and imaging findings including radiographs, CT, and MRI are described. The final diagnosis was made by histopathological, immunohistochemical, and/or ultrastructural study after biopsy.