Low-Grade Fibromyxoid Sarcoma: Clinical Study and Case Report

A Case Report on the Short-Term Recurrence of Low-Grade Fibromyxoid Sarcoma in the Maxillary Sinus

Low-grade fibromyxoid sarcoma (LGFMS) represents an exceptionally rare soft-tissue tumor, challenging to diagnose, and notorious for relentless recurrence and proliferation postsurgical resection. Primary symptoms of LGFMS include nasal congestion and rhinorrhea, accompanied by cheek numbness and distension. In this article, we report the diagnosis and treatment of a case of low-grade LGFMS originating in the maxillary sinus (MS). A 64-year-old male diagnosed with LGFMS of the left MS, undergoing 3 surgeries over a 1-year period with subsequent local recurrence. Following inconclusive postoperative pathology after the initial surgery, the patient experienced recurrence 2 months postsurgery, necessitating a second operation, which confirmed the LGFMS diagnosis pathologically. Radiation therapy commenced 1 month after the second surgery; however, recurrence transpired 6 months later, leading to a third operation. Subsequently, recurrence occurred again 8 months post third surgery, with the patient currently undergoing targeted therapy. This case underscores the distinct characteristics and therapeutic challenges inherent in LGFMS through the narrative of diagnosis and progression of LGFMS originating in the MS.

Low-Grade Fibromyxoid Sarcomas with the Maxillary Sinus Localization: A Case Report and Review of the Literature

A low-grade fibromyxoid sarcoma (LGFMS) is an extremely rare tumor first described by Evans in 1987. LGFMS is a type of soft tissue sarcoma characterized by a deceptively benign histological appearance but completely malignant behavior. LGFMS is usually seen in the deep soft tissues of the extremities and trunk. We have examined many reviews, case reports and case series previously published in PubMed and Google Scholar. To date, only five cases have been reported in the maxilla. LGFMS generally affects young adults, but it can also be seen in children and older adults. A radical surgical approach is the most recommended treatment option. LGFMS has a very low mitotic activity; therefore, it is considered that neither chemotherapy nor radiotherapy has a significant effect on long-term LGFMS prognosis. However, to date, there has been no study suggesting any protocol for the follow-up of patients with LGFMS. In this report, we present a case with LGFMS located in the maxillary sinus, in which despite radiotherapy following extensive surgical excision, the tumor recurred in a short period of three months and reached its former size.

Low-Grade Fibromyxoid Sarcoma Featuring an Unusual EWSR1-CREB3L2 Gene Fusion: Report of a Rare Case Arising in the Parotid Gland

Low-grade fibromyxoid sarcoma (LGFMS), also known as Evan's tumor, is a fibroblastic tumor with a deceptively bland morphology but a high metastasizing potential and late recurrence. It presents clinically as a slowly growing mass in the deep soft tissue of extremities and trunk. Morphologically, it shows a biphasic pattern with alternating fibrous and myxoid areas, whorling growth pattern, hypocellularity, and bland fibroblasts with curvilinear or arcuate vessels in between. Collagen rosettes with central hyalinization is a helpful feature but not specific. MUC-4 is the most sensitive immunostain in LGFMS. The majority of cases harbor a gene fusion in FUS - CREB3L2. Herein, we present a 23-year-old female patient with a slow growing painless mass in the left parotid gland, which was later diagnosed as LGFMS. Involvement of the head and neck region by LGFMS is uncommonly encountered. To date, only two cases within the parotid gland have been described.

Head and Neck Low-Grade Fibromyxoid Sarcoma: A Clinicopathologic Study of 15 Cases

Low-grade fibromyxoid sarcoma (LGFMS) is an uncommon mesenchymal tumor usually arising in the lower extremities and trunk. Only rare examples in the head and neck region have been reported. Fifteen cases of head and neck LGFMS were retrieved. MUC4 was performed on all cases. Results for smooth muscle actins, β-catenin, desmin, S100 protein, Epithelial membrane antigen (EMA) and STAT6 immunohistochemistry, as well as FUS rearrangement status, were recorded when available. Sites included neck (8), supraclavicular region (4) and orbit (1), parapharyngeal space (1) and lower lip (1). The age of the patients ranged from 3 to 97 years (median, 26 years). Tumors displayed classical morphologic features of LGFMS, as described. All cases (15/15) were positive for MUC4, and all cases tested (4/4) harbored FUS rearrangement. Variable positivity for EMA was identified in one case. Follow-up was available in 11 patients, ranging from 2 to 240 months (mean 71.4 months; median, 44 months). Three tumors recurred locally; none metastasized. In conclusion, although distinctly uncommon, LGFMS may arise in the head and neck region and should be distinguished from other more common spindle cell tumors in these locations. The morphologic, immunohistochemical and molecular genetic features of head/neck LGFMS are identical to those occurring elsewhere. The long-term metastatic risk of LGFMS in these locations remains to be fully elucidated.

Primary sclerosing epithelioid fibrosarcoma presenting as lombosciatic syndrome: Case report and literature review

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Sclerosing epithelioid fibrosarcoma (SEF) is a rare mesenchymal tumor.

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SEF appears to be a slowly growing tumor often present for several months or years before diagnosis.

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A tumor of the gluteal region may mimic a sciatic nerve pain.

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SEF has a poor prognosis with high risk of metastasis.

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The treatment is surgical.

Introduction and importance

Sclerosing epithelioid fibrosarcoma (SEF) is a rare variant of low grade fibrosarcoma, with specific histological and immunohistochemical features. SEF is a difficult to diagnose. The prognosis is poor with a 40% mortality rate.

Case presentation

We report a case of 45-year-old female patient who presented to our department with a history of right sciatalgia evolving for three months. On physical examination, a firmly not well-defined mass was found in the right gluteal region. The histological diagnosis revealed a SEF.

Clinical discussion

SEF appears to be a slowly growing tumor often present for several months or years before diagnosis. The 3-month delay of our diagnosis shows the difficulty arising from the inconclusive clinical of this tumor.

Conclusion

SEF of the gluteal region can induce sciatalgia. The diagnosis should be made as early as possible in order to improve the prognosis.

Low-grade fibromyxoid sarcoma incidentally discovered as an asymptomatic mediastinal mass: a case report and review of the literature

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor characterized by bland histological features and aggressive clinical course. The most common anatomic locations of occurrence are the lower extremities, thorax, inguinal area, and upper limbs. Primary mediastinal sarcomas are even rarer. To the best of our knowledge, only seven cases of primary mediastinal LGFMS have been reported in the literature. Here, we report a case of primary mediastinal LGFMS.

CASE PRESENTATION

A 26-year-old Pakistani man presented with fever and vomiting for the past 2 months. On a routine chest x-ray, a mediastinal mass was incidentally found. Computed tomography (CT) scan showed a large circumscribed lobulated soft tissue density mass lesion in an anterior mediastinum. Grossly, the resected mass measured 17.0 × 12.0 × 11.0 cm. The cut surface was gray white with a whorled-like appearance and foci of calcification and cystic changes. Histologically, a spindle cell lesion was seen with alternating myxoid and hyalinized areas. The shaped cells were arranged in bundles. Immunohistochemical staining showed positive reactivity patterns with MUC4 and focally for epithelial membrane antigen (EMA). The diagnosis was confirmed as LGFMS. The patient is free of symptoms and recurrence 22 months after the surgery.

CONCLUSION

In conclusion, we report a rare case of primary mediastinal LGFMS in a young male patient that was discovered incidentally. Our patient is on regular follow-up to look for evidence of recurrence as these tumors are prone to recurrences.

The Uncertainty of the Surgical Margin in the Treatment of Low Grade Fibromyxoid Sarcoma: a Case Report and Literature Review

Low grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue tumor appearing mainly in young adults. Despite its bland histological features, the tumor has a tendency toward late local recurrence and distant metastases even up to 45 years after the diagnosis. The treatment of choice in this type of neoplasm is a radical surgical excision with clear resection margins. We decided to present a case report of a 17-year-old patient with LGFMS of the right hip. Surgical resection of the tumor was performed, but in the histopathological examination was described the minimal resection margin (0.3 mm). The multi-specialist team composed of oncologist, radiologist, and pediatric surgeon based on the literature decided to widen the resection margin despite its obtainment during the primary operation. The scar after the first surgery and surrounding soft tissues with the bigger margin were resected. No evidence of cancerous infiltration was found in the second histopathological material. Patient has stayed under the routine control of pediatric surgeon, pediatric oncologist, and has not presented recurrence for 3 years. In conclusion, when the resection margin is uncertain after the primary surgery, the increase of the range of operation allows the prevention of the late recurrence of the disease.

A slow-growing anterior maxillary mass

A 43-year-old-male with no medical conditions presented to his dentist with a left maxillary swelling present for 1 year. His physical exam revealed a 2-cm × 2-cm, poorly demarcated, firm mass in the left anterior maxilla causing mobility of the associated teeth. He had a bluish discoloration of the anterior maxillary mucosa. A computed tomographic scan demonstrated a homogeneous and uniformly radiolucent, well-defined mass in the left anterior maxilla primarily involving the alveolus and the roots of teeth 7-12. The mass caused expansion and tooth displacement. An incisional biopsy was done and MUC 4 staining was diffusely positive so the diagnosis of low-grade fibromyxoid sarcoma (LGFMS) was made. He underwent wide local excision and reconstruction with a fibula free flap and a three-dimensionally printed, implant-retained prosthesis. The final pathology confirmed the diagnosis of LGFMS, stage pT4aN0M0, with negative margins. The patient had no evidence of recurrence at 1-year follow-up.

Low-grade fibromyxoid sarcoma of the maxillary sinus

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare malignant tumor. Moreover, only 3 cases of LGFMS originating from the nasal cavity and/or paranasal sinuses have been published so far.

METHODS

Two patients with histologically confirmed LGFMS of the maxillary sinus were primarily treated by open and endoscopic surgery. In one case adjuvant radiotherapy was indicated because of the uncertainty of the surgical margins.

RESULTS

Both surgeries were technically demanding and accompanied by significant bleeding from the tumors. Despite the extensive interventions there were no postoperative complications and no significant morbidity of the patients. There is no evidence of the disease 148 and 65 months after the treatment.

CONCLUSIONS

Regardless of the excellent post-treatment results, based on our experience, preoperative embolisation of the tumor should be considered prior to the surgical resection.

Low-grade fibromyxoid sarcoma: A report of the Cooperative Weichteilsarkom Studiengruppe (CWS)

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft-tissue tumor with benign histologic appearance, though fully malignant behavior is possible.

METHODS

Patients with LGFMS <21 years registered in Cooperative Weichteilsarkom Studiengruppe trials until 2017 were analyzed. Firstline treatment consisted of complete surgical resection whenever possible.

RESULTS

Median age of 31 patients was 10.9 years (first month to 17.1 years). Twenty-six tumors were confirmed to the tissue of origin (T1), four invaded contiguous structures (T2), one was TX. Eight were >5 cm. The best surgical result was resection with free margins (R0) in 24 and microscopic residuals (R1) in seven. Five-year event-free (EFS), 5-year local-relapse-free (LRFS), and 5-year overall-survival were 71 ± 18.6% confidence interval (CI) 95%, 76 ± 17.6% CI 95%, and 100%, respectively. Six patients suffered local relapse in a median of 1 year, one combined within 1.3 year and one metastatic relapse with lesions in the lung, back muscles, and thigh discovered in whole-body imaging 6 years after the first diagnosis. In univariate analysis, T status correlated with EFS (T1 79.6 ± 18.6%, T2 50.0 ± 49.0%, P = .038). Resection with free margins tends to be associated with better LRFS (R0 82.4 ± 18.6%, R1 53.6 ± 39.4%, P = .053). Among 24 patients with R0 resection, five (21%) suffered relapse, thereof three local, one metastatic, and one combined. Among seven patients with R1-resection, three (43%) suffered local relapse.

CONCLUSION

Special caution is advisable in T2 tumors. The metastatic potential with lesions in unusual sites indicates that affected patients need to be informed. If long-term follow-up with whole-body imaging is beneficial, it may be addressed in larger intergroup analyses. Further research in disease biology is essential for optimal treatment and follow-up care.

Intracranial Low-Grade Fibromyxoid Sarcoma: Findings on Electron Microscopy and Histologic Analysis

BACKGROUND

Low-grade fibromyxoid sarcoma is a rare tumor that manifests as a deep soft tissue mass characterized by a benign histology, but with potentially aggressive clinical behavior and a high rate of recurrence; primary intracranial sarcomas are even rarer. We present a case of primary intracranial low-grade fibromyxoid sarcoma, emphasizing its clinical, radiologic, and histologic features.

CASE DESCRIPTION

A 39-year-old woman presented with a recent history of headache and seizures. A right parietal mass was detected on computed tomography and magnetic resonance imaging, and she was subsequently operated on to remove the intracranial mass. Histologic examination of the resected tumor revealed mildly atypical fibroblastic cells embedded within a myxoid matrix. The diagnosis was confirmed by electron microscopy and cytogenetic analyses.

CONCLUSIONS

This report describes electron microscopic evaluation of intracranial low-grade fibromyxoid sarcoma, which has an extremely rare occurrence.

Low-Grade Fibromyxoid Sarcoma of the Lateral Skull Base: Presentation of Two Cases

Low-grade fibromyxoid sarcoma (LGFMS) is a rare slow-growing malignant tumour with a deceptively benign histologic appearance. Herein, we report two cases of LGFMS with variable clinical presentations. The first case was a 17-year-old female who referred to our department due to deaf ear on the right together with ipsilateral gag reflex impairment and globus sensation in the pharynx. The second case was a 35-year-old female with recurrent LGFMS, suffering from headaches, vertigo, and episodes of loss of consciousness. LGFMS of the temporal bone is a rare pathology, and to the best of our knowledge, no such cases have been reported before.

Low-grade fibromyxoid sarcoma of the external anal sphincter: a case report

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue tumor that has a tendency to grow in the deep soft tissue of the trunk and extremities. Despite its benign appearance, the tumor has a high recurrence rate and metastatic potential. LGFMS in the perineal space is rare, and only a few cases have been reported. We present the first case of LGFMS to be located at the external anal sphincter.

CASE PRESENTATION

A 27-year-old male patient admitted to our Surgical Department with perianal pain and swollen for a year. The digital rectal examination revealed a perianal mass. Oral metronidazole and analgesia were prescribed on suspicion of perianal abscess failed to alleviate the symptom; hence, the patient was scheduled for surgery. Intraoperative diagnosis revealed an encapsulated tumor in the external anal sphincter that extended from the perianal region orally to the pararectal space. The results of immunohistochemistry (MUC4 staining) and FUS gene rearrangement by fluorescence in situ hybridization confirmed the diagnosis of LGFMS.

CONCLUSIONS

This case is unique in terms of the location of the rare soft tissue tumor. Although LGFMS is considered low grade, its unpredictable behavior necessitates a long-term follow-up.

Low-grade fibromyxoid sarcoma involving the mandible: A diagnostic dilemma

Low-grade fibromyxoid sarcoma (LGFMS) is a distinctive variant of fibrosarcoma with a high metastasizing potential and is characterized by a long interval between tumor presentation and metastasis. LGFMS involving the maxillofacial region is a very rare entity with only six cases reported till date. LGFMS is characterized by its benign histological appearance, with spindle cells in whorling pattern, and collagenized and myxoid areas. The heterogeneous histological appearance makes the diagnosis challenging. Immunohistochemical staining has been reported by a number of authors, with some conflicting results, showing positivity with vimentin, but no immunoreactivity with antibodies to keratin, desmin, actin, S100 or epithelial membrane antigen. We present a case of a 35-year-old male patient who developed a mass on the left mandibular body region. The tumor was excised along with mental nerve at the level of the mental foramen. The tumor on pathologic and immunohistochemical evaluation was diagnosed as LGFMS.

[A case of low-grade fibromyxoid sarcoma of the colon]

Low-grade fibromyxoid sarcoma is a slowly growing soft tissue neoplasm that shows benign histologic features but may have clinical course of malignant disease. It has been reported to occur in the thigh, inguinal area, axilla, shoulder, neck, perineum or buttock. However, there have been few cases of abdominal organ involvement. A 21-year-old woman presented with a large palpable abdominal mass. A 7×4 cm sized round soft tissue tumor at right upper quadrant area was identified by abdominopelvic CT scan. Percutaneous ultrasound-guided biopsy revealed features of spindle cell tumor. On exploration, the tumor originated from transvers colon and was attached to gastrocolic ligament, transverse mesocolon and stomach. The tumor could be dissected with transverse colectomy and partial gastrectomy. The excised tumor, measuring 7×5×5 cm, was well demarcated and appeared as an ovoid mass with firm and myxoid cut surface. She was diagnosed with low-grade fibromyxoid sarcoma arising from transverse colon, and is currently being followed-up without recurrence or metastasis.

Rapidly enlarging low-grade fibromyxoid sarcoma with intracranial extension in a 5-year-old girl: case report

Low-grade fibromyxoid sarcoma (LGFMS) is a rare mesenchymal tumor that is characterized by a benign histology but potentially aggressive clinical behavior, with a high rate of recurrence and metastasis. It primarily occurs in young adults in the extremities, inguinal area, neck, or chest wall. There are rare reports of intracranial LGFMS in adults. In this report, the authors present the case of a 5-year-old girl who presented with a rapidly enlarging frontal scalp mass. Pathological examination of the resected mass demonstrated LGFMS. To the authors' knowledge, this is the only reported case of intracranial LGFMS in a child.

A Rare Pathology: Low-Grade Fibromyxoid Sarcoma of the Maxilla

Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor with a benign histologic appearance and fully malignant behavior. To date, only 5 cases of LGFMS in the maxillofacial region have been reported. This report describes the case of a 16-year-old boy who was referred to the authors' hospital with an intraosseous myxofibroblastic tumor, probably of the LGFMS type, of the right maxilla. Radical resection with wide safe margins and secondary reconstruction with a free forearm flap were performed. Six-month follow-up showed no sign of recurrence or metastasis. The authors review the scientific literature and discuss different tumor locations and treatment strategies for those in the maxillofacial region. The present case is the sixth reported case of LGFMS in the maxillofacial region (intraosseous LGFMS of the maxilla), adding another facet to the literature regarding this rare soft tissue tumor.

Low-Grade Fibromyxoid Sarcoma of the Head and Neck: A Clinicopathologic Series and Review of the Literature

Low-grade fibromyxoid sarcoma (LGFMS) is a deceptively bland malignancy with potential for late recurrence and metastasis, which usually occurs in the deep soft tissues of the extremities and trunk. Most LGFMSs harbor a characteristic gene fusion of FUS-CREB3L2, and recently MUC4 immunostaining has been found to be highly sensitive and specific for the diagnosis. We present a dedicated series of head and neck LGFMS, including the first reported laryngeal case, as well as a review of reported head and neck cases. The surgical pathology archives of our three institutions were searched for cases of LGFMS arising within the head and neck, and four cases were identified. The H&E slides were reviewed, and immunohistochemistry were performed for pancytokeratin, p63, p40, EMA, S100 protein, β-catenin, actin, CD34, and MUC4. The patients were 6, 43, 45, and 73 years old (mean 41.8 years) and included three males and one female. The tumors were located in the posterior cervical spine, facial skin, mandible, and larynx. The tumors were treated with surgical excision, and all four had histologic features typical for LGFMS including alternating myxoid and fibrous areas with prominent curvilinear vasculature. All tumors were MUC4 positive (100%), 2/4 (50%) were p63 positive, 1/4 (25%) showed focal EMA positivity; all 4 were negative for pancytokeratin, p40, S100 protein, β-catenin, actin, and CD34. LGFMS is a low grade sarcoma that rarely develops in the head and neck. Due to its rarity, a pathologist may not consider LGFMS in the differential diagnosis of spindle cell neoplasms within the head and neck. Immunohistochemical staining is helpful, but stains should be selected carefully to avoid misdiagnosis.

Deeply located low-grade fibromyxoid sarcoma with FUS-CREB3L2 gene fusion in a 5-year-old boy with review of literature

Background

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue tumor typically affecting young to middle-aged adults. Despite its otherwise benign histologic appearance and indolent nature, it can have fully malignant behavior, and recurrence and metastasis may occur even decades later.

Case history

We report a case of LGFMS in the left lower leg of a 5-year-old Japanese boy. A magnetic resonance imaging (MRI) uncovered a well-demarcated intra-gastrocnemial tumor measuring 27 × 20 mm with a slightly high intensity on T1WI and heterogeneously high intensity on T2WI. Histologically, the tumor was composed of bland spindle-shaped cells with a whorled growth pattern. The tumor stroma was variably hyalinized and fibromyxoid with arcades of curvilinear capillaries and arterioles with associated perivascular fibrosis. Although LGFMS is known to affect children under 18 years of age, it is extremely rare in infants and children under 5 years of age. Despite the young age, this patient was accurately diagnosed by the typical histology and the detection of a FUS-CREB3L2 gene fusion.

Conclusion

Although LGFMS in children tends to be located superficially, this case presented with an intramuscular tumor in the region of the gastrocnemius. To the best of our knowledge, this is the first case of deep LGFMS arising in a child younger than 5 years of age. The patient is still alive with no evidence of the disease 4 months after diagnosis.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_163