Fibromyxoid sarcoma in a four-year-old child: case report and review of the literature

Case report: Primary pleural low-grade fibromyxoid sarcoma in a 4-year-old boy with molecular confirmation

Low-grade fibromyxoid sarcoma (LGFMS) is a rare malignant fibroblastic tumor, principally affecting the deep tissues of the proximal trunk and extremities in young adults. However, primary pleural LGFMS is extremely rare, and only three cases have been reported in the previous English literature without genetic confirmation. Furthermore, the historical pleural LGFMS cases were all adults, and the primary pleural LGFMS in children has never been reported to date. Here, we presented a primary pleural LGFMS in a 4-year-old boy with detailed clinical, pathological, and molecular results. Histologically, the current tumor showed typical alternating collagenous and myxoid areas, containing spindled or oval tumor cells arranged in a whorled and short fascicular pattern. In some areas, the tumor cells exhibited moderate atypia, and mitotic figures were identified but without the identification of giant collagen rosettes. Immunohistochemically, all the neoplastic cells showed strong and diffuse positivity for MUC4. Genetically, FUS gene rearrangement was revealed by fluorescence in-situ hybridization (FISH), and subsequently, next-generation sequencing (NGS) and polymerase chain reaction (PCR) further demonstrated the FUS::CREB3L2 fusion transcript. To the best of our knowledge, this is the first case of primary pleural LGFMS with the identification of FUS gene rearrangement and FUS::CREB3L2 fusion in a 4-year-old child. Our study expands the age range of pleural LGFMS and highlights the combination of morphological, immunohistochemical, and molecular analyses in such challenging cases.

Low-grade Fibromyxoid Sarcoma: Treatment Outcomes and Efficacy of Chemotherapy

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) is a rare sarcoma subtype with a generally indolent pattern of clinical behaviour, but treatments for advanced disease are limited.

PATIENTS AND METHODS

A retrospective search of a prospectively maintained institutional database identified 102 patients treated from December 1994 to August 2018. We evaluated the outcome of patients and the efficacy and safety of non-surgical therapies in LGFMS.

RESULTS

Ninety-four out of 102 (92.2%) underwent primary resection, seven (6.9%) were treated with systemic therapy and one (1.0%) is currently being treated with pre-operative radiotherapy. The RECIST 1.1 response rate to first-line chemotherapy was 0%, and median progression-free survival was 1.84 months (95% confidence intervaI=0.10-3.6 months).

CONCLUSION

Conventional systemic therapy has limited efficacy in advanced LGFMS.

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

Low-grade fibromyxoid sarcoma with nuclear pleomorphism arising in the subcutis of a child

Low-grade fibromyxoid sarcoma (LGFMS) represents a rare soft tissue tumor that was first characterized in 1987. LGFMS usually presents as a large, deeply situated mass in adults and is characterized by deceptively bland histopathologic features. LFGMS is less common in superficial soft tissue and in children. It is distinctly uncommon for LGFMS to exhibit nuclear pleomorphism. Herein, we present a case of a 10-year-old male who presented with a subcutaneous back mass that displayed features typical for LGFMS as well as scattered large, hyperchromatic and pleomorphic nuclei. The constellation of clinicopathologic features, including the young age of the patient, the small size and superficial location of the tumor and the presence of scattered nuclear pleomorphism are all unusual features for LGFMS. Fluorescent in situ hybridization (FISH) with a break-apart probe for FUS revealed the presence of a FUS gene rearrangement confirming the diagnosis of LGFMS. This case highlights the importance of maintaining a high index of suspicion for LGFMS even in the context of small, superficially-located tumors, pediatric patients or tumors with scattered nuclear pleomorphism.

Low-grade fibromyxoid sarcoma, a deceptively benign tumor in a 5-year-old child

Low-grade fibromyxoid sarcoma (LGFMS) is very uncommon in the pediatric population with only 20% of reported cases under the age of 18. The youngest reported case to date has been in a 4-year-old child. Lesions are usually slow growing and asymptomatic, and locations described in children have included paravertebral, thigh and intrathoracic. Although benign in appearance, these lesions can behave aggressively, with local recurrence and distant metastases primarily to lungs. These lesions can be resistant to the usual chemotherapy and radiotherapy with surgical resection being the treatment of choice. We report a case of a 5-year-old boy who presented with a mass in the left buttock.

Fibromyxoid Sarcoma of the Kidney. A Case Report

Low grade fibromyxoid sarcoma is an uncommon soft tissue tumor.

We present the case of a 83–year-old female who developed large mass in the right kidney. A nephrectomy was performed. The tumor measured 18,5×17,5×11,5 cm and on pathology evaluation was diagnosed as low grade fibromyxoid sarcoma. Currently, the patient is doing well without evidence of local recurrence and distant metastasis.

Low grade fibromyxoid sarcoma of the Kidney is a very rare tumor. The metastasizing potential is high. Sometimes long interval between tumor presentation and metastasis is observed. The treatment of choice is surgery. The role of radiotherapy and chemotherapy is uncertain.

Low grade fibromyxoid sarcoma: a case report and review of the literature

Low grade fibromyxoid sarcoma (LGFMS) is a distinctive variant of fibrosarcoma with a high metastasizing potential and sometimes long interval between tumour presentation and metastasis. We present the case of a 50-year-old male who developed a large mass in the posterior aspect of his lower left thigh. The tumor was excised with preservation of the neurovascular structures surrounded by the mass. The tumour measured 11 x 10 x 9 cm and on pathology evaluation was diagnosed as LGFMS. Due to the relative rarity of LGFMS, there is no dedicated protocol regarding follow-up recommendations. In order to early diagnose possible metastasis it is important to inform the patients about the longstanding metastatic potential of the disease.

Low-grade fibromyxoid sarcoma of the medial vastus: a case report

Low-grade fibromyxoid sarcoma (LGFMS) was first described by Evans in 1987, and since then, just over 150 cases have been reported, showing the rarity of this tumor. We report the clinical case of a 56-year-old man with a swelling on the distal third of the left thigh. The mass had grown in the course of 1 year and was surgically excised, obtaining complete resolution. Immuno-histological examination demonstrated the lesion to be a LGFMS, defined as a benign tumor but with a high incidence of local and distant recurrence (5-10%). At 2-year follow-up the patient was disease-free, confirming the efficacy of the surgical excision. In literature, the frequency of incomplete excision of LGFMS due to inappropriate diagnosis is stressed. It is this element that contributes most to the high rate of recurrence. We recommend that the eventuality of observing this rare tumor be borne in mind, and that care be taken to perform a complete, ample excision.

The benefits of molecular pathology in the diagnosis of musculoskeletal disease : part I of a two-part review: soft tissue tumors

Bone and soft tissue metabolic and neoplastic diseases are increasingly characterized by their molecular signatures. This has resulted from increased knowledge of the human genome, which has contributed to the unraveling of molecular pathways in health and disease. Exploitation of this information has allowed it to be used for practical diagnostic purposes. The aim of the first part of this two-part review is to provide an up-to-date review of molecular genetic investigations that are available and routinely used by specialist musculoskeletal histopathologists in the diagnosis of neoplastic disease. Herein we focus on the benefits of employing well characterized somatic mutations in soft tissue lesions that are commonly employed in diagnostic pathology today. The second part highlights the known somatic and germline mutations implicated in osteoclast-rich lesions of bone, and the genetic changes that disturb phosphate metabolism and result in a variety of musculoskeletal phenotypes. Finally, a brief practical guide of how to use and provide a molecular pathology service is given.

[Fibromyxoid sarcoma of kidney]

OBJECTIVE

To report a case of fibromyxoid sarcoma of the kidney.

CLINIC REPORT

A 28-year-old male patient attended the urological outpatient clinic for left varicocele associated with abdominal pain, fatigue, and weight loss.

CONCLUSIONS

Low-grade fibromyxoid sarcoma of the kidney is an uncommon tumor. Surgery is the treatment of choice for this condition. Pathological analysis provides the final diagnosis.

Fibromyxoid sarcoma in a 4-year-old boy: case report and review of the literature

The authors report on the case of a low-grade fibromyxoid sarcoma (LGFMS) with giant rosettes in a 4-year-old boy. The tumor arose in the paravertebral region and had infiltrated the vertebral canal between L2 and S1. A review of the literature indicates that this is one of the youngest patients diagnosed with a tumor of this type, and spinal involvement had never been reported with LGFMS.

Superficial Low-grade Fibromyxoid Sarcoma (Evans Tumor)

Low-grade fibromyxoid sarcoma (LGFMS), usually a deeply situated mass in adults, is uncommon in superficial soft tissue and in children. Nineteen superficial LGFMS from our files were studied for clinicopathologic features, the latter including tumor size, growth pattern, cellularity, collagen rosettes, vascularity, nuclear atypia, mitotic rate, necrosis, and immunophenotype. The patients included 12 males and 7 females who ranged in age from 2 to 70 years (mean, 29 years). There were 7 children. Tumor locations included the lower extremity (8), buttock (3), trunk (3), vulva/inguinal region (2), upper extremity (2), and unspecified subcutis (1). Clinical and histologic submitting diagnoses were mainly benign except for 3 cases, submitted as low-grade sarcoma, with only one as superficial LGFMS. The mean tumor size was 4.2 cm (range, 1.6-18 cm). Of 15 with evaluable resections, 5 had focal ink on tumor and 2 of these had known negative wider reexcisions. The tumors were relatively well circumscribed with low to moderate cellularity. The tumors alternated from myxoid zones with prominent curvilinear vasculature to collagenous fascicular zones. Collagen rosettes with peripheral round epithelioid cells and focal ischemic necrosis were present in 6 cases each. Mitotic rate was low (mean 1.6/50 HPF). Tumor cells were positive for vimentin and some were focally positive for actins, CD68, and EMA. CD34, keratins, and S-100 protein were negative. Follow-up (mean, 44 months; range, 10-84 months) on 16 patients demonstrated 14 with no evidence for disease, 2 with local recurrences at 5 and 16 months, but no metastases. Superficial LGFMS is more common than previously recognized and may affect children at a higher rate (7 of 19, 37%) than that for deep LGFMS. The prognosis is good and appears to be better than that for deep LGFMS.

Low grade fibromyxoid sarcoma of the falciform ligament: a case report

Background

Low grade fibromyxoid sarcomas (LGFMS) are very rarely seen. They commonly arise from deep soft tissues of the lower extremities. Very few cases of intra-abdominal location have been reported.

Case presentation

We report a 37 year old man who presented with an abdominal mass and dragging pain. Pre-operative imaging suggested the possibility of a subcapsular hemangioma of liver.

Conclusions

Laparoscopy was useful to locate the tumor as arising from falciform ligament and made the subsequent surgery simpler. This is one of the large fibromyxoid sarcomas to be reported.

End-stage renal interstitial fibrosis in an adult ten years after ifosfamide therapy

A 33-year-old male presented with end-stage renal failure. Renal biopsy showed severe interstitial fibrosis without glomerulopathy or vasculopathy. More than 10 years previously the patient had been successfully treated for recurrent rhabdomyosarcoma. The treatment included ifosfamide, a drug known to cause acute tubular dysfunction. Though a possible synergistic effect of previous radiation which was well within accepted tolerance limits cannot be excluded, it would appear that ifosfamide was almost certainly the major cause of the late onset chronic renal disease.

Low-grade fibromyxoid sarcoma and hyalinizing spindle cell tumor with giant rosettes: a clinicopathologic study of 73 cases supporting their identity and assessing the impact of high-grade areas

Low-grade fibromyxoid sarcoma (LGFMS) is a rare sarcoma characterized by bland histologic features and a paradoxically aggressive clinical course. The hyalinizing spindle cell tumor with giant rosettes (HSCT) is a closely related tumor characterized by the presence of giant collagen rosettes. Only a single example of a metastasizing HSCT has been reported. A small subset of both LGFMS and HSCT display areas of increased cellularity and atypia which qualify as intermediate- to high-grade sarcoma; the significance of these features has not been definitively assessed. We present the clinicopathologic features of 77 cases of LGFMS and HSCT to determine the degree of overlap of these two lesions, their biologic behavior, and the significance of the occasional presence of intermediate- to high-grade sarcoma within both. The patients (33 female, 40 male) ranged from 3 to 78 years of age (median, 34 yrs). Fourteen cases occurred in patients less than 18 years of age. The tumors measured from 1 to 23 cm (median, 4.5 cm) and occurred predominantly in the trunk and lower extremities in both the deep (66 cases) and superficial (7 cases) soft tissues. In 15 cases, the tumor was present > 1 year before diagnosis. All tumors showed predominantly the typical hypocellularity and bland cytologic features of typical LGFMS; however, areas of hypercellularity and nuclear enlargement and hyperchromatism were identified in 12 of 73 (16%) and 7 of 73 (10%), respectively. Necrosis and mitotic activity >5/50 high-powered fields (HPF) were present in 6 of 73 (8%) and 5 of 73 (7%), respectively. Epithelioid areas were present in 33 of 73 (45%) and rosettes in 22 of 73 (30%). Follow up (54 cases; range, 2-192 mos; median, 24 mos; mean, 38 mos) showed 5 recurrences, 3 metastases, and 1 death. The diagnosis of LGFMS or HSCT was made prospectively in 51 patients; none had metastatic disease. Two of the metastatic tumors were LGFMS and one was a HSCT. LGFMS may occur more often in the pediatric population and show a much wider histologic spectrum than previously thought. A significant number of LGFMS possess inconspicuous collagen rosettes characteristic of HSCT, indicating that these two tumors are ends of a common spectrum rather than distinct entities. HSCT, like LGFMS, are low-grade sarcomas with metastatic potential. The presence of focal areas of intermediate- to high-grade sarcoma does not portend a worse outcome in the short term. The better prognosis reflected in this study compared with previous ones might reflect the fact that all were initially diagnosed as sarcomas and treated with aggressive surgery. The fact that the only three patients to develop metastatic disease were patients whose LGFMS or HSCT was identified retrospectively supports this concept.

Low-grade fibromyxoid sarcoma

Described is a low-grade fibromyxoid sarcoma (LGFMS) of the abdominal wall muscles in a 38-year-old black woman. There was no evidence of metastatic disease. A 5.2-kg LGFMS - the largest case ever reported - was resected. One year after surgery, the patient is alive without any sign of local recurrence or distant metastasis. Follow-up comprises abdominal and thoracic CT scans at 6-month intervals.