Cases Of Low-grade Fibromyxoid Sarcoma Research Articles

A rare case report of pancreatic low-grade fibromyxoid sarcoma (LGFMS)

BackgroundLow-grade fibromyxoid sarcoma (LGFMS) is an uncommon neoplasm generally affecting muscle tissue. It presents rarely in abdominal viscera and even more rarely occurs in the pancreas. All types of pancreatic sarcomas are uncommon, and LGFMS is a rarer still. We present the case of an LGFMS in the pancreas. Because of its rarity, there are no guidelines for appropriate treatment or summations of the natural course of this illness.Case presentationWe present the case of a 49-year-old female who presented with epigastric pain. She had a prior history of three episodes of acute pancreatitis many years earlier. A CT revealed a pancreatic body mass, which was biopsied. Pathology returned LGFMS. The patient underwent a distal pancreatectomy and splenectomy. She did well after the case and did not require further intervention.ConclusionThough it is exceedingly rare, cases of pancreatic LGFMS should be reported in order to guide clinical decisions. LGFMS has been shown to have high malignant potential in other tissues, and there is no reason to think pancreatic masses will be different. By building a body of evidence about these rare tumors, patient care will benefit.

Low-grade fibromyxoid sarcoma of the maxillary sinus.

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

Cytomorphologic findings of low-grade fibromyxoid sarcoma

Low-grade fibromyxoid sarcoma (LGFMS) is a rare fibroblastic tumor characterized by a prolonged clinical course and malignant biological behavior. Given its deceptively bland cytomorphology, a diagnosis can be quite challenging notably on fine-needle aspiration (FNA). In an attempt to shed light on some of the distinctive cytomorphologic characteristics, this study was conducted to review all cases of LGFMS in our database, correlating available clinical data, immunohistochemical findings, and molecular analysis. This series included 20 FNAs from 18 patients with a histologically confirmed LGFMS diagnosis from 3 large academic institutions. Detailed cytomorphologic analysis for each case was documented in conjunction with corresponding clinical characteristics and provided ancillary testing. Out of 14 adequate FNA samples, 9 (64.2%) demonstrated a mixture of fibrous and myxoid pattern; the majority of cases were composed of deceptively bland tumor cells with rare nuclear pleomorphism and nuclear membrane irregularities. A MUC4 immunostain was performed on 5 specimens; all tested positive (100%). FUS rearrangement was detected in 4 out of 5 cases (80%). Follow-up information revealed 5-year recurrence in 1 case and metastatic disease in 2 cases, to the lung/pleura (8 years) and fourth rib (1 year), respectively. The presence of bland spindle cells and associated with myxoid matrix material, in the appropriate clinical setting, can suggest LGFMS and direct additional confirmatory testing. A definitive diagnosis of LGFMS on FNA requires adequate sampling, familiarity with key cytomorphologic features, acquisition of diagnostic material for a cell block preparation and ancillary testing, and clinicoradiologic correlation.

Two-Year Survival of Low-Grade Fibromyxoid Sarcoma of the Vulva Managed by Surgical Therapy

Abstract Background: Low-grade fibromyxoid sarcoma (LGFMS) of the vulva is an exceedingly rare condition. Only two cases of LGFMS arising from the vulva have been reported in the literature. Case: ...

Low-grade fibromyxoid sarcoma: a rare condition with high proliferation

Low-grade fibromyxoid sarcoma (LGFMS) is a type of high metastatic potential of the fibrosarcomas. Most of the time there is a long interval between tumor presentation and metastasis. We present 2 cases of LGFMS. The first is a 31-year-old female with a mass in anterior aspect of her left thigh, and the other is a 68-year-old female with mass in posterior of her neck. Both cases underwent operation for several times and confirmed as LGFMS histopathologically, there is no exact protocol for postoperative follow-up to detect early metastases according to the relative variety of LGFMS. So informing the patients about the long-standing metastatic potential of their disease is important.

A rare case of low-grade fibromyxoid sarcoma with ossification which was radiologically detected as apparent calcification and histopathologically proven

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft-tissue malignant neoplasm with a deceptively benign histological appearance and a potential for late recurrence and metastasis. LGFMS cases with significant ossification are extremely rare. To our knowledge, only three cases of LGFMS with bone formation which is detected as apparent calcification by radiological examinations and proven by histopathology have been reported. Here, we report the fourth such case. A 39-year-old female presented with a 10-year history of a painless tumor in her right buttock. Computed tomography images showed multiple foci of intratumoral calcification. A needle biopsy specimen of the tumor revealed a spindle cell neoplasm with hyalinizing/collagenous stroma and ossification. The tumor cells were immunohistochemically positive for MUC4 and the molecular analysis of the tumor detected FUS-CREB3L2 fusion. Pathological diagnosis of LGFMS was made. Total resection of the tumor with wide margins was performed, and histology of the resected sample showed multiple foci of intratumoral ossification.

Low-Grade Fibromyxoid Sarcoma in the Left Gluteal Region Presenting as Sciatic Nerve Pain

Low-grade fibromyxoid sarcoma is a slowly growing soft tissue neoplasm, mostly affecting young individuals. It usually arises in a deep soft tissue of the lower limbs and trunk, but few cases of low-grade fibromyxoid sarcoma that presents sciatic nerve pain have been reported. We report a 34-year-old woman with a low-grade fibromyxoid sarcoma originating in the left gluteal region that initially presented as sciatic nerve pain; she had experienced this type of pain for 5 years before visiting our hospital. Magnetic resonance imaging revealed a tumor in the left gluteal region. After needle biopsy revealed it to be a low-grade fibromyxoid sarcoma, we performed the wide resection. Intra-operative findings revealed no tumor invasion into the sciatic nerve. No recurrence or metastasis has been detected 6 months post-surgery. Oncologists who encounter patients with sciatic nerve pain should consider the possibility of less common causes such as the low-grade fibromyxoid sarcoma found in our patient.

Huge mesenteric low-grade fibromyxoid sarcoma: A case report and review of the literature.

Low-grade fibromyxoid sarcoma is a rare soft tissue tumor which has been mostly reported in lower extremities; however, it can also occur in other parts of the body such as head and neck and abdominal wall, but its occurrence in the abdominal cavity and mesentery of bowel is an extremely rare event and has very rarely been reported. Herein, we report our experience with a 24-year-old lady with a huge mesenteric mass, turned out to be low-grade fibromyxoid sarcoma. This case is the largest one reported in the English literature. We will also discuss about the previously reported cases of low-grade fibromyxoid sarcoma in the English literature.

Primary gastric low-grade fibromyxoid sarcoma with FUS-CREB3L1 fusion – A hitherto undescribed origin of Evans tumor

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue neoplasm with a deceptively benign histological appearance. Only several LGFMS cases originating from the gastrointestinal tract have been reported, but all of them are from the small intestine or colon. Here, we describe a case of gastric LGFMS that was proven to have a characteristic FUS-CREB3L1 fusion gene. A 54-year-old Japanese female complained of epigastralgia. Abdominal computed tomography revealed a solid mass probably originating from the lessercurvature of the gastric body and protruding outside the gastric wall. Under the clinical diagnosis of suspicious gastrointestinal stromal tumor of the stomach, gastric wedge resection including the tumor was done. The macroscopic finding showed a mass approximately 8.0cm in maximal diameter with white-tan cut surface, arising from the gastric wall. Histological examination revealed a mesenchymal tumor consisting of blunt spindle cells with occasional collagen rosettes and inflammatory cells. Tumor was immunohistochemically positive for MUC4 and the molecular analysis using formalin-fixed paraffin embedded tissue detected FUS-CREB3L1 fusion which is a minor fusion gene type in LGFMS. Thus, the pathological diagnosis of gastric LGFMS was confirmed. To the best of our knowledge, the present case is the first one of LGFMS arising from the stomach in the English literature.

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.

A genetic dichotomy between pure sclerosing epithelioid fibrosarcoma (SEF) and hybrid SEF/low-grade fibromyxoid sarcoma: a pathologic and molecular study of 18 cases.

Sclerosing epithelioid fibrosarcoma (SEF) is a rare soft tissue tumor exhibiting considerable morphologic overlap with low-grade fibromyxoid sarcoma (LGFMS). Moreover, both SEF and LGFMS show MUC4 expression by immunohistochemistry. While the majority of LGFMS cases are characterized by a FUS-CREB3L1 fusion, both FUS-CREB3L2 and EWSR1-CREB3L1 fusions were recently demonstrated in a small number of LGFMS and SEF/LGFMS hybrid tumors. In contrast, recent studies pointed out that SEF harbor frequent EWSR1 rearrangements, with only a minority of cases showing FUS-CREB3L2 fusions. In an effort to further characterize the molecular characteristics of pure SEF and hybrid SEF/LGFMS lesions, we undertook a clinicopathologic, immunohistochemical and genetic analysis of a series of 10 SEF and 8 hybrid SEF/LGFMS tumors. The mortality rate was similar between the two groups, 44% within the pure SEF group and 37% in the hybrid SEF/LGFMS with a mean overall follow-up of 66 months. All but one pure SEF and all hybrid SEF/LGFMS-tested cases showed MUC4 immunoreactivity. The majority (90%) of pure SEF cases showed EWSR1 gene rearrangements by fluorescence in situ hybridization with only one case exhibiting FUS rearrangement. Of the nine EWSR1 positive cases, six cases harbored CREB3L1 break-apart, two had CREB3L2 rearrangement (a previously unreported finding) and one lacked evidence of CREB3L1/2 abnormalities. In contrast, all hybrid SEF/LGFMS tumors exhibited FUS and CREB3L2 rearrangements. These results further demarcate a relative cytogenetic dichotomy between pure SEF, often characterized by EWSR1 rearrangements, and hybrid SEF/LGFMS, harboring FUS-CREB3L2 fusion; the latter group recapitulating the genotype of LGFMS.

Recurrent EWSR1-CREB3L1 Gene Fusions in Sclerosing Epithelioid Fibrosarcoma

Sclerosing epithelioid fibrosarcoma (SEF) and low-grade fibromyxoid sarcoma (LGFMS) are 2 distinct types of sarcoma, with a subset of cases showing overlapping morphologic and immunohistochemical features. LGFMS is characterized by expression of the MUC4 protein, and about 90% of cases display a distinctive FUS-CREB3L2 gene fusion. In addition, SEF is often MUC4 positive, but is genetically less well studied. Fluorescence in situ hybridization (FISH) studies have shown involvement of the FUS gene in the majority of so-called hybrid LGFMS/SEF and in 10% to 25% of sarcomas with pure SEF morphology. In this study, we investigated a series of 10 primary tumors showing pure SEF morphology, 4 cases of LGFMS that at local or distant relapse showed predominant SEF morphology, and 1 primary hybrid LGFMS/SEF. All but 1 case showed diffuse expression for MUC4. Using FISH, reverse transcription polymerase chain reaction, and/or mRNA sequencing in selected cases, we found recurrent EWSR1-CREB3L1 fusion transcripts by reverse transcription polymerase chain reaction in 3/10 pure SEF cases and splits and deletions of the EWSR1 and/or CREB3L1 genes by FISH in 6 additional cases. All 5 cases of LGFMS with progression to SEF morphology or hybrid features had FUS-CREB3L2 fusion transcripts. Our results indicate that EWSR1 and CREB3L1 rearrangements are predominant over FUS and CREB3L2 rearrangements in pure SEF, highlighting that SEF and LGFMS are different tumor types, with different impacts on patient outcome.

EWSR1-CREB3L1 Gene Fusion

Low-grade fibromyxoid sarcoma (LGFMS) is an uncommon sarcoma with a deceptively bland-looking morphology that disguises its malignant clinical behavior. It shows distinctive chromosomal translocations resulting in fusion of FUS with the CREB3L2 gene in most cases and CREB3L1 in rare cases. Thus molecular studies are particularly helpful in the diagnosis of this bland-looking sarcoma. We report 2 cases of LGFMS serendipitously found to harbor a novel alternative EWSR1-CREB3L1 gene fusion, as confirmed by DNA sequencing of reverse transcriptase-polymerase chain reaction products and fluorescence in situ hybridization. One patient was a child who presented with a subcutaneous nodule on the lower leg, and the other was a middle-aged woman who had a mass lesion over the proximal thigh. Morphologically, one case showed a spindle cell tumor with hyalinization and giant rosettes, whereas the other showed classical histology of LGFMS with focal metaplastic bone formation. Immunostaining for MUC4 showed extensive positive staining. Our findings therefore expand the spectrum of gene fusions that characterize LGFMS and suggest that the EWSR1 gene may substitute for the function of FUS in gene fusions of sarcoma.

Low-grade Fibromyxoid Sarcoma of the Small Intestine

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue tumor that typically involves the deep soft tissues of the extremities. However, LGFMS has been described in other locations including the head and neck, retroperitoneum, and mesentery. Translocations involving the FUS gene located at 16p are considered to be highly specific for the diagnosis of this tumor when present in conjunction with the appropriate morphologic appearance. We report 4 cases of LGFMS arising in the small bowel. The patients' ages (3 female, 1 male) ranged from 52 to 71 years (median, 61 y). None of the patients had a history of soft tissue sarcoma. An intramural tumor was presented in all cases, ranging from 4.5 to 14.5 cm in greatest diameter (mean, 10 cm). Microscopically, the tumors consisted of an admixture of hypocellular, heavily collagenized zones and more cellular myxoid nodules, containing a greater number of neoplastic cells arranged around characteristic curvilinear vessels. By immunohistochemistry, all tumors were positive for vimentin and negative for smooth muscle actin, CD117, CD34, and S100 protein. Fluorescence in situ hybridization for rearrangement of the FUS locus at 16p11 was positive in 3 informative cases. Follow-up information was available in 3 cases; 2 patients are alive without disease and another patient died of disease. We conclude that LGFMS should be included in the differential diagnosis of fibrous or myxoid spindle cell tumors of the gastrointestinal tract. On the basis of limited follow-up, the natural history of enteric LGFMS seems to be similar to that of LGFMS in other locations, with potential for late metastases.

Low-grade fibromyxoid sarcoma: a clinicopathologic study of 18 cases, including histopathologic relationship with sclerosing epithelioid fibrosarcoma in a subset of cases

Low-grade fibromyxoid sarcoma (LGFMS) is an uncommon tumor with diverse histopathologic features. It has been found to be histopathologically and genetically related to hyalinizing spindle cell tumor with giant rosettes. Lately, sclerosing epithelioid fibrosarcoma (SEF) has been identified as another rare variant of fibrosarcoma. Very few studies have addressed the aspect of its histopathologic relationship with LGFMS. The present study was conducted to critically analyze the clinicopathologic features of a series of LGFMS cases, including identification of cases with histopathologic similarity with SEF. During a 7-year period, 18 LGFMS cases were diagnosed in 9 male and 9 female patients, had ages ranging from 10 to 69 years (median, 32.5 years), and were most commonly identified in the lower extremities (8 cases, or 44.4%). Most cases (16, 88.8%) showed "classic" features of LGFMS with mild (13 cases, or 72.2%) to moderate atypia (5 cases) and nil mitosis (12 cases, or 66.6 %). Variable features included whorling tumor growth pattern, small rosettes, perivascular hyalinization, and amianthoid-like collagen, along with epithelioid differentiation and nuclear pseudoinclusions within tumor cells. Four cases (22.2%) with large collagenous rosettes were diagnosed as hyalinizing spindle cell tumor with giant rosettes. Distinct SEF-like areas were observed in 6 cases (33.3%). On immunohistochemistry, consistent vimentin positively reinforced fibroblastic lineage of the tumor. Therapeutically, all 4 of 7 cases with available follow-up details, which underwent wide excisions, have been free of disease at 5 to 61 months. Eight excisions with unclear margins included 3 cases free of disease (24, 36, and 52 months) and 1 case with recurrence and metastasis. Two cases of marginal excision had tumor recurrences, including 1 case that recurred after 10 years. Low-grade fibromyxoid sarcoma is an uncommon sarcoma with diverse histopathologic features. Histopathologic relationship exists between LGFMS and SEF in a few cases. An LGFMS is optimally managed with surgical wide excision and follow-up.

MUC4 Is a Highly Sensitive and Specific Marker for Low-grade Fibromyxoid Sarcoma

Low-grade fibromyxoid sarcoma (LGFMS) is a distinctive fibroblastic neoplasm that is characterized by alternating collagenous and myxoid areas, deceptively bland spindle cell morphology, a whorling architecture, and a t(7;16) translocation involving FUS and CREB3L2. Owing to variable morphology and a lack of discriminatory markers, LGFMS can be difficult to distinguish from benign mesenchymal tumors and other low-grade sarcomas. Gene expression profiling has identified differential upregulation of the mucin 4 (MUC4) gene in LGFMS compared with histologically similar tumors. MUC4 is a transmembrane glycoprotein that functions in cell growth signaling pathways; aberrant MUC4 expression has been reported in various carcinomas. We investigated MUC4 protein expression by immunohistochemistry in LGFMS and in other soft tissue tumors to determine the potential diagnostic use of this novel marker. Whole-tissue sections of 309 tumors were evaluated: 49 LGFMSs (all with FUS gene rearrangement confirmed by fluorescence in situ hybridization), 40 soft tissue perineuriomas, 40 myxofibrosarcomas, 20 cellular myxomas, 20 solitary fibrous tumors, 20 low-grade malignant peripheral nerve sheath tumors, 20 cases of desmoid fibromatosis, 20 neurofibromas, 20 schwannomas, 20 monophasic synovial sarcomas, 20 cases of dermatofibrosarcoma protuberans, 10 myxoid liposarcomas, and 10 extraskeletal myxoid chondrosarcomas. The LGFMS cases included 7 with marked hypercellularity, 4 with prominent hemangiopericytoma-like vessels, 3 with giant collagen rosettes, 3 with epithelioid morphology, 2 with focal nuclear pleomorphism, and 2 with areas of sclerosing epithelioid fibrosarcoma. All 49 LGFMS cases (100%) showed cytoplasmic staining for MUC4, which was usually diffuse and intense. All the other tumor types were negative for MUC4, apart from 6 (30%) monophasic synovial sarcomas. In conclusion, MUC4 is a highly sensitive and quite specific immunohistochemical marker for LGFMS, and can be helpful to distinguish this tumor type from histologic mimics.

Hyalinizing spindle cell tumor with giant rosettes

Low-grade fibromyxoid sarcomas are uncommon deep-seated soft tissue neoplasms that exhibit a deceptively benign appearance microscopically. The finding of a linear or whorled array of spindled cells with few or no mitoses in a characteristic myxoid stroma can pose diagnostic dilemmas. Recurrences are common, and late metastases have been recorded. A closely related tumor, the so-called hyalinizing spindle cell tumor with giant collagen rosettes (HSCTGR), has also been described, with both the neoplasms having a similar cytogenetic abnormality and clinical behavior. Because of the similarities, both lesions are considered to be a single entity within the spectrum of low-grade sarcomas. Two cases of HSCTGR occuring in the lower limb are described in this report.

The clinical significance of the FUS-CREB3L2 translocation in low-grade fibromyxoid sarcoma

BackgroundLow-grade fibromyxoid sarcoma (LGFMS) is a rare soft-tissue neoplasm with a deceptively benign histological appearance. Local recurrences and metastases can manifest many years following excision. The FUS-CREB3L2 gene translocation, which occurs commonly in LGFMS, may be detected by reverse-transcriptase polymerase chain reaction (RT-PCR) and fluorescence in situ hybridisation (FISH). We assessed the relationship between clinical outcome and translocation test result by both methods.MethodsWe report genetic analysis of 23 LGFMS cases and clinical outcomes of 18 patients with mean age of 40.6 years. During follow-up (mean 24.8 months), there were no cases of local recurrence or metastasis. One case was referred with a third recurrence of a para-spinal tumour previously incorrectly diagnosed as a neurofibroma.ResultsResults showed 50% of cases tested positive for the FUS-CREB3L2 translocation by RT-PCR and 81.8% by FISH, suggesting FISH is more sensitive than RT-PCR for confirming LGFMS diagnosis. Patients testing positive by both methods tended to be younger and had larger tumours. Despite this, there was no difference in clinical outcome seen during short and medium-term follow-up.ConclusionsRT-PCR and FISH for the FUS-CREB3L2 fusion transcript are useful tools for confirming LGFMS diagnosis, but have no role in predicting medium-term clinical outcome. Due to the propensity for late recurrence or metastasis, wide excision is essential, and longer-term follow-up is required. This may identify a difference in long-term clinical outcome between translocation-positive and negative patients.

Intramuscular Low-grade Fibromyxoid Sarcoma: A Case Report

Low-grade fibromyxoid sarcoma (LGFMS) is a rare neoplasm that commonly arises in the deep soft tissues of the lower extremities, particularly in the thigh. LGFMS occurs preferentially in young male adults. The microscopic appearance of LGFMS exhibits bland fibroblastic spindle cells with a whorled or linear arrangement in fibrous and myxoid areas. Although LGFMS has a deceptively benign histologic appearance, local recurrence and late metastases have frequently been reported. Diagnosis of LGFMS is still difficult because of its characteristic bland-looking histologic features that can be confused with other benign or low-grade fibromyxoid lesions. Although immunohistochemical staining can offer an overview of the differential diagnosis of myxoid tumors of soft tissue, it is sometimes limited for diagnosis of LGFMS. However, recent cytogenetic and molecular analyses have provided significant improvements in the diagnosis of LGFMS. Such analyses have demonstrated that most cases of LGFMS have a characteristic t(7,16)(q33;p11) translocation, resulting in the FUS-CREB3L2 fusion gene. We report a 29-year-old female who presented with a LGFMS located in the soleus muscle of her left lower leg. Preoperative imaging suggested the possibility of an intramuscular histiocytoma of the left soleus muscle. In conclusion, diagnosis of LGFMS can be challenging in routine practice in surgical pathology because of its bland-looking features. The immunohistochemical and ultrastructural findings were consistent with the fibroblastic properties of LGFMS. Cytogenetic and/or molecular genetic analyses can be used as ancillary diagnostic tools for LGFMS.

Low-grade fibromyxoid sarcoma: a clinicopathological analysis of 9 cases

To study the clinicopathological features, immnophenotype and differential diagnosis of low-grade fibromyxoid sarcoma (LGFMS). The clinical, radiological and pathological features of 9 cases of LGFMS were reviewed. The patients consisted of six males and three females with ages ranging from 11 to 65 years (mean 31.4 years). Clinically, most cases presented as slowly growing painless masses located in the extremities, trunk and neck. Two cases had a history of a rapid recent enlargement. Three cases presented with recurrent diseases after incomplete resection. Ultrasound showed heterogeneous signal. Precontrast CT and T1-weighted MRI showed a nodular mass of low to isodensity, while contrast-enhanced CT and T2-weighted MRI demonstrated contrasting zonal areas of hypo/hyperintensity. The tumors measured 3 to 16 cm (mean 7.7 cm), with a fibrous to myxoid appearance on cut surface. Histologically, they were composed of alternating collagenous and myxoid areas. A transition between the two areas could be identified. Giant rosette-like structures were observed in 3 cases. The center of the giant rosettes was composed of eosinophilic collagen, which showed centrifugal in arrangement. There was also gradual transition between the giant rosettes and the fibromyxoid component. On high magnification, the tumor was composed of ovoid to spindle-shaped cells with hyperchromatic nuclei. Nuclear atypia was inconspicuous. The tumor cells were arranged mostly in interlacing fascicles or whorls. Vessels were not prominent and necrosis was absent. Immunohistochemically, the tumor cells showed unique staining for vimentin, consistent with a fibroblastic differentiation. LGFMS is a distinctive low grade fibroblastic sarcoma of young adults. Recognizing the characteristics of the rare entity may help to avoid misdiagnosis. Wide local excision is recommended to avoid local recurrences.