Intramuscular Myxoma Research Articles

Thoracolumbar Paravertebral Intramuscular Myxoma Presenting With Mechanical Back Pain: A Case Report and Review of the Literature

Background and Aim: Intramuscular myxomas are uncommon benign tumors that are rarely seen in the paraspinal musculature. They might present with neurological symptoms if situated near the spinal cord or may present with nonspecific symptoms such as back pain. Case Presentation: The case of this study was a 46-year-old female presented with back pain that was exacerbated with movement. A thoracolumbar magnetic resonance imaging revealed a T2 hyperintense 35x25x85 mm mass that extends craniocaudally within the right-sided paraspinal muscles with heterogeneous contrast enhancement on T1 sequence images. Using a paramedian incision, paraspinal muscles were dissected, and a rubbery mass was palpated within. The tumor was mobilized in all quadrants and removed with its pseudocapsule. The tumor internally had a gel-like substance with rubbery margins. The patient was discharged without complications. Conclusion: To our knowledge, this is the 16th case of paraspinal intramuscular myxoma in the literature. Even though it is a rare entity, one must be vigilant for pathologies within the paraspinal muscles in patients with back pain

Intramuscular myxoma: unusual observation of spontaneous tumor size shrinkage.

Soft tissue tumors, whether benign or malignant, may grow over time or remain stable, but they usually do not spontaneously decrease in size. However, there are exceptions, such as inflammatory conditions, desmoid tumors, or benign cysts. Intramuscular myxomas are benign soft tissue tumors that typically present as a solitary, slow-growing, painless mass. They are generally treated by surgical resection, after which recurrence is rare. Here, we present a brief series of three unusual cases of intramuscular myxomas that spontaneously decreased in size. They were located in the cervical region, the right lower extremity, and the paravertebral lumbar region. Imaging findings and percutaneous biopsies confirmed the diagnosis in all cases. Follow-up imaging showed a spontaneous reduction in lesion volume over time, far exceeding the amount of tissue sample removed during biopsy. This unusual observation of spontaneous shrinkage may call into question the subsequent therapeutic approach to these lesions.

INTRAMUSCULAR MYXOMA OF THE VASTUS LATERALIS MUSCLE: A CASE REPORT

Introduction: Intramuscular myxoma is a rare benign soft tissue tumor which usually affects large muscle groups in patients aged between forty and sixty years. It is composed of hypocellular myxoid tissue. Incidence of intramuscular myxoma varies from 0.1 to 0.3 per 100,000 individuals. The aim of this study: to present the process of diagnosis and treatment of a patient with the rare soft tissue tumor. Case description: A 41-year-old female came to the Orthopedic Clinic with a 2-year history of a lump on the lateral side of her right thigh. Noticeable growth of the lesion and pain complaints started after skiing injury 7 months before the examination. The magnetic resonance imaging test demonstrated encapsulated intramuscular mass which measured 6 x 2 x 2 cm located in Vastus lateralis muscle. Due to an increasing pain and a significant size of the lesion, the patient was qualified for an excisional biopsy. After an excision, the lesion was found on histopathology to be an intramuscular myxoma. The patient did not complain of any neurological deficits, walking disorders. The follow-up imaging examination 3 months after surgery show no recurrence and the further observation was planned.

A rare case of fibrous dysplasia in the mandible: a case report

Background: Fibrous dysplasia (FD) is a benign fibro-osseous lesion of the bone which can be monostotic FD and the polyostotic form. Polyostotic FD with café-au-lait spots of the skin and hormonal imbalances is called McCune–Albright syndrome. Besides, Mazabraud syndrome is characterized by polyostotic FD and intramuscular myxomas. FD has its onset during childhood or early adolescence and usually occurs within the first or second decade of life.
 The mode of presentation of the FD of the jaw ranges from asymptomatic to dental anomalies, pain, and facial asymmetry. Given the clinical history and radiological assessment, cystic lesions have some important differential diagnoses which range from cystic ameloblastoma, fibrous dysplasia, aneurysmal bone cyst, and odontogenic keratocyst.
 Case report: This presents a 19-year-old female who presented to the maxillofacial surgeons’ clinic with a referral from a peripheral hospital. Her major complaint was right-sided facial swelling which was noticed 4 years before the presentation. A plain radiograph revealed an expansile lesion of the mid-right mandible appearing as a well-outlined, fairly oval multiloculated cystic radiolucent mass with multiple internal septations. A preliminary diagnosis of a complex cystic right jaw mass with benign features was made with possible differential diagnoses such as ameloblastoma, fibrous dysplasia, aneurysmal bone cyst, and odontogenic keratocyst were suggested as possible differential diagnoses. Finally, she had an excision biopsy with a histological diagnosis of fibrous dysplasia. The outcome of the surgery was satisfactory at one year review.
 

Intramuscular Myxoma, Mimicking a Psoas Abscess

We report a clinical observation of intramuscular myxoma, mimicking a psoas abscess. Surgical minimally invasive treatment of the disease has been suggested. This clinical observation shows an example of the effective use of minimally invasive treatment methods in surgical practice, as an alternative to open surgery.

Genetic characterization of intramuscular myxomas.

Introduction: Intramuscular myxomas are benign tumors that are challenging to diagnose, especially on core needle biopsies. Acquired chromosomal aberrations and pathogenic variants in codon 201 or codon 227 in GNAS complex locus gene (GNAS) have been reported in these tumors. Here we present our genetic findings in a series of 22 intramuscular myxomas. Materials and methods: The tumors were investigated for the presence of acquired chromosomal aberrations using G-banding and karyotyping. Pathogenic variants in codon 201 or codon 227 of GNAS were assessed using direct cycle Sanger sequencing and Ion AmpliSeq Cancer Hotspot Panel v2 methodologies. Results: Eleven tumors carried chromosomal abnormalities. Six tumors had numerical, four had structural, and one had both numerical and structural chromosomal aberrations. Gains of chromosomes 7 and 8 were the most common abnormalities being found in five and four tumors respectively. Pathogenic variants in GNAS were detected in 19 myxomas (86%) with both methodologies. The detected pathogenic variants were p.R201H in nine cases (seven with abnormal and two with normal karyotypes), p.R201C in five cases, all with normal karyotypes, p.R201S in three cases (two with abnormal and one with normal karyotype), p.R201G in one case with a normal karyotype, and p.Q227E in one case with a normal karyotype. Conclusion: Firstly, our data indicate a possible association between chromosomal abnormalities and GNAS pathogenic variants in intramuscular myxomas. Secondly, the presence of the rare pathogenic variants R201S, p.R201G and p.Q227E in 26% (5 out of 19) of myxomas with GNAS pathogenic variants shows that methodologies designed to detect only the common "hotspot" of p.R201C and p.R201H will give false negative results. Finally, a comparison between Ion AmpliSeq Cancer Hotspot Panel v2 and direct cycle Sanger sequencing showed that direct cycle Sanger sequencing provides a quick, reliable, and relatively cheap method to detect GNAS pathogenic variants, matching even the most cutting-edge sequencing methods.

Nerve sheath myxoma masqueraded as intramuscular myxoma: an extremely rare tumor with unusual location - a case report and literature review.

The authors present the first reported case of NSM in the anterior tibialis muscle in a 39-year-old man presented as deep swelling in the left leg. NSM is difficult to diagnose clinically or using standard imaging techniques; MRI and ultrasonography cannot differentiate it from other anomalies. Histopathology alone is not enough to distinguish NSM from neurothekeomas, which were considered synonymous in the past. They can be distinguished by using immunohistochemical markers. Soft tissue tumors in lower extremity muscles are somewhat difficult to diagnose. Excision of the tumor by a specialized orthopedic surgeon and histopathological/immunohistochemical analysis were the only avenues to correctly diagnose the NSM.

Myxoid Soft Tissue Tumors: A 20-Year Experience on Fine Needle Aspiration with Application of the Proposed WHO Reporting System for Soft Tissue Cytopathology

Introduction: Myxoid soft tissue tumors represent a heterogenous group of neoplasms. The study presented our experience on cytopathology of myxoid soft tissue tumors on fine needle aspiration (FNA) and aimed to apply the recently proposed WHO system for reporting soft tissue cytopathology. Material and Methods: We performed a 20-year retrospective search of our archives to identify all FNAs performed on myxoid soft tissue lesions. All cases were reviewed, and the WHO reporting system was applied. Results: 129 FNAs performed in 121 patients (62 males; 59 females) showed a prominent myxoid component, accounting for 2.4% of all soft tissue FNAs. The FNAs were performed on 111 (86.7%) primary tumors, 17 (13.2%) recurrent tumors, and one (0.8%) metastatic lesion. A spectrum of non-neoplastic and neoplastic lesions including both benign and malignant neoplasms was identified. Overall, the most common tumors identified were myxoid liposarcoma (27.1%), intramuscular myxoma (15.5%), and myxofibrosarcoma (13.1%). The sensitivity and specificity of FNA regarding the nature of the lesion (benign vs. malignant) were 98% and 100%, respectively. When the WHO reporting system was applied, the frequency of the categories was as follows: benign (7.8%), atypical (34.1%), soft tissue neoplasm of uncertain malignant potential (18.6%), suspicious for malignancy (3.1%), and malignant (36.4%). The risk of malignancy calculated in each category was as follows: benign (10%), atypical (31.8%), soft tissue neoplasm of uncertain malignant potential (50%), suspicious for malignancy (100%), and malignant (100%). Conclusion: A diverse group of non-neoplastic and neoplastic lesions can show a prominent myxoid component on FNA. The WHO reporting system for soft tissue cytopathology is easily applicable and appears to correlate well with the malignant potential of myxoid tumors.

An unusual presentation of a myxoma at the tip of the tongue: a case report and literature review

Myxomas are benign mesenchymal tumours, comprised of bland spindle cells embedded in an abundant myxoid stroma. Soft tissue intramuscular myxomas typically occur within the large skeletal muscles of the limbs. Myxomas infrequently occur in the head and neck region, where they develop almost exclusively in the jaw bones and are of odontogenic origin. Only 33 cases of intramuscular myxoma in the head and neck region have been reported.1 The occurrence of myxoma within the soft tissue or muscle of the tongue is particularly rare, with only four cases reported in the literature to date.

A Rare Variant of Mazabraud’s Syndrome Overlapping with McCune-Albright Syndrome with a Clinical Review: A Case Report

Mazabraud syndrome (MS) is a rare and sporadic disorder. It is mainly characterized by fibrous dysplasia (FD) of single or multiple bones and intramuscular myxomas (IM). Data on the prevalence since it was first reported, clinical features, and prognosis are extremely scarce. We report a case of a 59-year-old woman with IM and polyostotic FD. She also had multiple cafe’-au-lait spots suggestive of McCune-Albright syndrome (MAS). On magnetic resonance imaging, there are masses with well-defined heterogeneous enhancement, accompanied by an inner cyst in the vastus lateralis muscle and femur. These radiological results are identical to those of FD. After surgical intervention with excision of intramuscular soft-tissue mass, a diagnosis of IM of MS was confirmed. Given that cafe’-au-lait spots also appeared, the patient was diagnosed with a variant of MS with some of the clinical characteristics of MAS.

A 73-Year-Old Man with an Incidental Diagnosis of Deltoid Intramuscular Myxoma Following a History of Trauma

Patient: Male, 73-year-old Final Diagnosis: Intramuscular myxoma Symptoms: Shoulder pain Medication:— Clinical Procedure: — Specialty: General and Internal Medicine • Orthopedics and Traumatology Objective: Rare disease Background:Intramuscular myxomas are rare and benign soft-tissue tumors of uncertain differentiation. Predisposing or precipitating factors have not yet been reported. Activating mutation in GNAS (exons 8 and 9) is detected in >90% of sporadic cases. The role of chronic myopathy, tendinopathy, or trauma to muscles in the etiology of these neoplasms is not known. We report an unusual case of a deltoid mass found following longstanding rotator cuff tendinopathy and a recent fall, later confirmed to be an intramuscular myxoma on biopsy.Case Report:A 73-year-old man with a 5-year history of left shoulder pain and rotator cuff tear presented with intractable pain in his left shoulder after a recent fall at home. Physical examination was suggestive of a rotator cuff injury and magnetic resonance imaging (MRI) of the left shoulder revealed a 2.7×2.5×3.7cm T1 hypo- and T2 hyperin-tense oblong mass-like signal abnormality with heterogeneous, predominantly peripheral enhancement within the deltoid muscle concerning for a malignant mass. Surgical resection was carried out along with left reverse total shoulder replacement, and histopathology revealed findings consistent with an intramuscular myxoma.Conclusions:Intramuscular myxomas are rare, benign tumors. This case report presents one such myxoma incidentally found in a patient with longstanding rotator cuff tendinopathy and a recent fall. Although this co-occurrence is likely incidental, further research and case series review of similar presentations may influence postulations of the pathophysiology of myxomas.

Diagnostic and Therapeutic Pathways of Intramuscular Myxoma.

Intramuscular myxomas (IMMs) are benign tumors. Evidence regarding diagnostic and therapeutic pathways is rare, and guidelines do not exist due to their low incidence. The aim of this study was a retrospective analysis at a university cancer center and the interdisciplinary re-evaluation of the individual diagnostic and therapeutic procedures. Overall, 38 patients were included in the study. IMMs occurred mostly in middle-aged women. At the time of first consultation, 57.9% had few symptoms or were asymptomatic. In 92.1% of the cases, the tumor was localized in the extremities. The lower extremity was affected in 73.7%. The average size of IMMs was 5.0 cm. The proximally located tumors in the gluteus, thighs, and upper arms were significantly larger (p = 0.02) than the distally-located tumors in the forearms and lower legs. An MRI was performed in 97.4%. Based on imaging, an IMM was suspected in 5.6% by radiologists and in 54.1% by musculoskeletal surgeons. An incision biopsy was performed in 68.4% and led in 100.0% to the right histopathological diagnosis. In total, 89.5% of IMMs were resected. Postoperative complications requiring revision occurred in 8.8%. Recurrences or degenerations of IMMs were not reported in any of these cases.

A case report on Intramuscular Myxoma

Intramuscular myxoma is a rare mesenchymal tumour reported to be in 1 in one lakh population and most frequently diagnosed in females (~57%) patients between fifth and sixth decades of life. These tumours are commonly benign in nature and it usually favours in thighs, shoulders, buttocks. A very rare site of this tumour is forearm mainly found in elderly patients. Generally, myxoma is composed of gelatinous material that has a myxoid histologic appearance. They are slow growing, asymptomatic and submucosal masses. There is no known underlying cause for this condition but it is suspected that it can occur due to the combination of genetic and environmental risk factors. In this case report local reoccurrence has not been reported after resection. We treated the patient with surgical excision and that seems to be the most effective treatment. After surgical excision if reoccurrence occurs histopathologic diagnosis should be reviewed. The tumor may be low grade myxoid neoplasm and treatment plan may be changed. An elderly patient presenting with a solitary soft tissue tumour should be thoroughly investigated to rule out the soft tissue sarcomatous conditions, which in many ways mimic the intramuscular myxoma.

Artificial intelligence significantly improves the diagnostic accuracy of deep myxoid soft tissue lesions in histology

Deep myxoid soft tissue lesions have posed a diagnostic challenge for pathologists due to significant histological overlap and regional heterogeneity, especially when dealing with small biopsies which have profoundly low accuracy. However, accurate diagnosis is important owing to difference in biological behaviors and response to adjuvant therapy, that will guide the extent of surgery and the need for neo-adjuvant therapy. Herein, we trained two convolutional neural network models based on a total of 149,130 images representing diagnoses of extra skeletal myxoid chondrosarcoma, intramuscular myxoma, low-grade fibromyxoid sarcoma, myxofibrosarcoma and myxoid liposarcoma. Both AI models outperformed all the pathologists, with a significant improvement of accuracy up to 97% compared to average pathologists of 69.7% (p < 0.00001), corresponding to 90% reduction in error rate. The area under curve of the best AI model was on average 0.9976. It could assist pathologists in clinical practice for accurate diagnosis of deep soft tissue myxoid lesions, and guide clinicians for precise and optimal treatment for patients.

Mazabraud’s Syndrome: Literature Review and Report of A Case Series.

Mazabraud’s syndrome is a condition that combines fibrous dysplasia with of single or multiple intramuscular myxomas, which etiology remains relatively unknown. We present three cases of this uncommon disease. All patients received marginal resection of their symptomatic myxomas, with histopathological confirmation of the lesions after surgery and follow-ups of more than one year. Mazabraud’s syndrome corresponds to a very rare disease. The management of these patients should be focused on the treatment of symptoms and avoidance of complications. Fracture risk is to be studied and treated if necessary. Conclusions: This disease is probably underestimated. It’s important to report cases in order to advance in the knowledge of this syndrome.

Intramuscular myxoma in the gluteus maximus muscle after continuous intramuscular injections

Joint Diseases and Related Surgery (JDRS), the official journal of the Turkish Joint Diseases Foundation, is an international, peer-reviewed, immediate open access journal. All published articles in JDRS has been free for everyone, without embargo, since 1990.

Extent of Extraskeletal Manifestations of Fibrous Dysplasia/McCune-Albright Syndrome in Patients with Mazabraud's Syndrome.

Mazabraud's syndrome (MZB) is a rare condition in which fibrous dysplasia of bone/the McCune-Albright syndrome (FD/MAS) co-exists with intramuscular myxomas. Both FD and the myxomas harbor the GNAS-mutation. Recent studies have shown that extraskeletal, GNAS-related features are associated with a more severe phenotype of FD/MAS. However, patients with MZB are often only seen by orthopedic surgeons. We therefore evaluated MZB patients seen in tertiary referral centers from the Netherlands (LUMC), USA (National Institutes of Health) and France (INSERM UMR 1033 (Lyos), Hôpital Edouard Herriot). All FD/MAS patients known in these centers with an additional diagnosis of a myxoma were included. Demographic information and data on disease extent and extraskeletal manifestations of FD/MAS such as precocious puberty (PP) or café-au-lait patches (CAL) were retrieved from patient's medical records. Thirty MZB patients were included: 20 women (67%) and 10 men (33%). Patients received a diagnosis of MZB (median 42years, range 16-19) significantly later than the diagnosis of FD/MAS (median 30years, range 0-60), p < 0.01. Twenty-six patients were diagnosed with polyostotic disease (87%). In 97% the myxoma was located near the skeletal FD lesion. The combination of MZB and MAS was made in 13 patients in whom PP (n = 7), CAL (n = 7), GH-excess (n = 3) and hyperthyroidism (n = 3) were present. Other extraskeletal features were (multinodular) goiter (n = 2) and thyroid cysts (n = 1). Furthermore, in this cohort of patients with MZB several (pre-)malignant tumors were observed; ductal carcinoma in situ of the breast in 3 patients (10%), breast cancer in 1 patient (3.3%), intra pancreatic mucinous neoplasms in 3 patients (10%) and liver adenomas in 2 patients (6.6%). A total of 47% of patients with MZB had an additional extraskeletal feature such as an endocrinopathy. In MZB, 87% of patients suffer from polyostotic FD, 43% of patients have extraskeletal GNAS-features such as an hyperfunctioning endocrinopathy and 30% (pre-)malignant tumors. We therefore advocate that MZB patients should undergo a complete screening and long-term follow-up for extent of bone disease, but also extraskeletal GNAS features of FD/MAS.

A case of intramuscular lumbar myxoma: Uncertainty in the preoperative diagnosis of a spinal soft tissue tumour

We report an uncommon case of a 76-year-old woman who presented with lower back pain, an intermittent L5 radiculopathy and a right palpable paraspinal mass. Imaging studies revealed a 7-cm lumbar paraspinal pseudo-cystic soft tissue tumour developed in the paravertebral musculature, without a clear radiological diagnosis. Gross total surgical resection was performed, resulting in complete resolution of pain. Histopathological studies revealed an intramuscular (IM) myxoma.With a low positive predictive value of radiological work-up and a poor yield of percutaneous biopsies, surgery remains the mainstay treatment for these rare soft tissue tumours of the lumbar spine. Intramuscular myxomas show excellent postoperative results.

Treatment of Polyostotic Fibrous Dysplasia With Intravenous Ibandronate

Introduction: Fibrous Dysplasia (FD) is proliferation of fibrous tissue within the bone marrow causing osteolytic lesions and pathologic fractures. Polyostotic FD in combination with a thigh myxoma is consistent with Mazabraud syndrome (MS). Bisphosphonates have shown promise in treatment and prevention of progression of FD. Clinical Case: A 34-year-old male with an unremarkable family history developed left thigh pain shortly after Whipple’s procedure for pancreatic cancer in 2017. Imaging revealed a 9cm left thigh mass and multiple femoral and pelvic intramedullary lesions compatible with FD. The thigh mass was removed and final pathology revealed an intramuscular myxoma with +GNAS mutation. Given clinical picture, genetics raised concern for MS and recommended endocrinology consultation. Patient reported chronic pain in chest, abdomen, back and multiple joints requiring spinal stimulator placement. Labs displayed subclinical hyperthyroidism and thyroid uptake scan revealed a right toxic MNG. Hence ablation was performed. Labs also displayed elevated alkaline phosphatase (ALP) bone isoenzyme of 103 IU/L (RR 0–72). Thoracic X-ray revealed chronic endplate vertebral compression fracture with no history of trauma and normal DEXA scan. NM bone scan was consistent with FD in skull, humerus, scapula, ribs, pelvis, femur and tibia. Given chronic pain at multiple sites and compression fractures, therapy with IV Zoledronic acid was given after Vitamin D was repleted. Within several hours, patient developed acute phase reaction (APR) with severe bone pain requiring hospitalization. ALP levels normalized within 1 year of therapy. 1.5 years post therapy, patient experienced a grand mal seizure. MRI brain revealed multifocal abnormal bone marrow within the calvarium, facial bones and skull base. Labs again displayed elevated ALP but new hypophosphatemia and an elevated serum FGF23. Given progression of skeletal disease as indicated by elevated FGF23, additional off-label injectable treatment options were reviewed and patient agreed to Ibandronate. Discussion: Majority of evidence for bisphosphanate treatment in FD is derived from observational studies, which report variable symptomatic improvement despite improvement of bone turnover markers. Oral anti-resorptives are commonly used but were not an option for our patient given history of Barrett’s esophagus and Whipple’s surgery. Pamidronate was first used in the treatment of FD with variable success rates. Denosumab is also being considered as a therapeutic option in FD however there are insufficient case reports to outline safety profile. Zoledronic acid is commonly used however our patient developed APR to the first dose and refused retrial. Given progression of disease, treatment was recommended. Therefore a milder anti-resorptive such as Ibandronate was considered which warrants further investigation in the treatment of FD.

Surgical Treatment of Intramuscular Myxoma.

Intramuscular myxoma (IM) is a rare benign myxoid tumor that may be challenging to differentiate from sarcoma in small amounts of biopsied material. Although IM appears to be well-circumscribed macroscopically, it infiltrates the adjacent edematous muscle microscopically. The recommended treatment is resection, but there is controversy with regard to the appropriate surgical margin. This study aimed to clarify which surgical procedure that should be applied when the preoperative diagnosis is IM and how to manage treatment if the postoperative diagnosis turns out to be a sarcoma. We retrospectively examined 55 IM patients treated from January 1982 to December 2014. Patient characteristics, tumor location, tumor size, radiograph, preoperative and postoperative pathological reports, surgical techniques, treatment outcome, and complications were reviewed. The patients were followed up on for at least 5years. All patients were confirmed not to have Mazabraud syndrome. In the 55 IM patients examined, the mean patient age was 48years and most were female. The most common tumor locations were in the muscles of the thighs (47%) and buttocks (20%). The mean tumor diameter was 5cm. Wide resection and marginal resection were performed in 24 and 31 patients, respectively. The mean follow-up duration was 19years. No local recurrence, malignant transformation, or complications were observed. Marginal resection is suitable in patients whose preoperative diagnosis is IM, as it is able to prevent local recurrence and allows for the preservation of muscle and muscle fascia. If the postoperative diagnosis turns out to be myxoid sarcoma, minimum surgical contamination makes additional wide resection less invasive.