Subcutaneous ossifying lipoma: case report and review of the literature

Adipose and lipoma stem cells: A donor-matched comparison

Lipomas are slow growing benign fat tumors that develop in soft tissues of the mesoderm. Thus, the specific (dys-)function of mesenchymal stem cells (MSCs) has been suggested in the development of lipomas, but details of the tumor pathogenesis remain unclear. Existing studies comparing stem cells from native adipose (adipose stem cells [ASCs]) and lipomatous tissues (LSCs) have reported contradicting findings. However, harvesting ASCs and LSCs from different individuals might have influenced proper comparison. Therefore, we aimed to characterize donor-matched ASCs and LSCs to investigate metabolic activity, proliferation, capability for tri-linear differentiation (chondrogenesis, adipogenesis, osteogenesis), and the secretome of mature adipocytes and lipomacytes. Both stem cell types did not differ in metabolic activity, but ASCs demonstrated stronger proliferation than LSCs. While there was no difference in proteoglycan accumulation during chondrogenic differentiation, adipogenesis was higher in ASCs, with more lipid vacuole formation. Conversely, LSCs showed increased osteogenesis by higher calcium deposition. Lipomacytes showed stronger secretory activity and released higher levels of certain adipokines. Our findings indicated that LSCs possessed important characteristics of MSCs, including ASCs. However, LSCs' low proliferation and adipogenic differentiation behavior did not appear to account for enhanced tissue proliferation, but the secretome of lipomacytes could contribute to lipomatous neoplasm.

Giant hand osteolipoma: Case Report

Hand lipomas are rare in the hand, and they account for less than 1% of tumors. Osteolipoma is a rare variant of lipoma that is associated with bone metaplasia. It presents as a painless tumor that can cause symptoms when compressing adjacent structures. Magnetic resonance imaging (MRI) is the imaging study of choice. The treatment is surgical resection, with no recurrences being reported. We present the case of a patient with a giant subfascial hand osteolipoma, which, to the best of our knowledge has not yet been reported in the literature.

Ossifying Lipoma in Costal Arches That Suggest Extensive Pulmonary Involvement: Case Report

Background:

Lipomas are the most common benign soft tissue tumors in the general population. These lesions can appear on any part of the body and usually develop in the subcutaneous superficial tissue. Lipomas that show ossifying changes are very rare, representing less than 1% of the reported lipomas. They usually manifest as hard nodular lesions in the head and neck, the extremities, the sternoclavicular region, and the subcutaneous tissue in general; they are rare in the costal arches.

Case presentation:

We report the case of a patient with a history of multiple diseases and 2 tumor-like lesions with internal lytic areas detected in the fourth right costal arch and in the eighth left costal arc; we describe his clinical manifestations, radiological and laboratory findings as well as the pathological results and outcome.

Conclusions:

Ossifying lipomas are rare benign tumors with asymptomatic clinical presentation. It is important to perform an adequate radiological differentiation from other more aggressive lesions such as liposarcomas.

Investigation of stemness and multipotency of equine adipose-derived mesenchymal stem cells (ASCs) from different fat sources in comparison with lipoma

BACKGROUND

Adipose tissue-derived mesenchymal stem cells (ASCs) offer a promising cell source for therapeutic applications in musculoskeletal disorders. The appropriate selection of ASCs from various fat depots for cell-based therapy is challenging. The present study aims to compare stemness and multipotency of ASCs derived from retroperitoneal (RP), subcutaneous (SC), and lipoma (LP) fat to assess their usefulness for clinical application.

METHODS

Equine ASCs from the three fat tissue sources were isolated and characterized. The cell viability, proliferation, and self-renewal were evaluated using MTT, sulforhodamine B, and colony forming unit (CFU) assays. Stem cell relative marker CD44, CD90, and CD105 and tumor marker CA9 and osteopontin (OPN) expression were quantified using RT-qPCR. Multipotency of ASCs for adipogenic, osteogenic, and chondrogenic differentiation was examined by quantifying Oil Red O and Alizarin Red S staining, alkaline phosphatase activity (ALP), and expression of differentiation relative markers. All data were statistically analyzed using ANOVA.

RESULTS

RP fat-derived ASCs showed a higher cell proliferation rate compared to SC and LP derived cells. In contrast, ASCs from lipoma displayed a lower proliferation rate and impaired CFU capacities. The expression of CD44, CD90, and CD105 was upregulated in RP and SC derived cells but not in LP cells. RP fat-derived cells displayed a higher adipogenic potential compared to SC and LP cells. Although ASCs from all fat sources showed enhanced ALP activity following osteogenic differentiation, SC fat-derived cells revealed upregulated ALP and bone morphogenetic protein-2 expression together with a higher calcium deposition. We found an enhanced chondrogenic potency of RP and SC fat-derived cells as shown by Alcian blue staining and upregulation of aggrecan (Aggre), cartilage oligomeric matrix protein precursor (COMP), and collagen 2a1 (Col2a1) expression compared to LP. The expression of OPN and CA9 was exclusively upregulated in the ASCs of LP.

CONCLUSIONS

The results provide evidence of variation in ASC performance not only between normal fat depots but also compared to LP cells which suggest a different molecular regulation controlling the cell fate. These data provided are useful when considering a source for cell replacement therapy in equine veterinary medicine.

Stem Cells Derived from Lipoma and Adipose Tissue-Similar Mesenchymal Phenotype but Different Differentiation Capacity Governed by Distinct Molecular Signature

Lipomas are benign adipose tissue tumors of unknown etiology, which can vary in size, number, body localization and cell populations within the tissue. Lipoma-derived stem cells (LDSCs) are proposed as a potential tool in regenerative medicine and tissue engineering due to their similar characteristics with adipose-derived stem cells (ADSCs) reported so far. Our study is among the first giving detailed insights into the molecular signature and differences in the differentiation capacity of LDSCs in vitro compared to ADSCs. Mesenchymal stem cell phenotype was analyzed by gene expression and flow cytometric analysis of stem cell markers. Adipogenesis and osteogenesis were analyzed by microscopic analysis, cytochemical and immunocytochemical staining, gene and protein expression analyses. We showed that both LDSCs and ADSCs were mesenchymal stem cells with similar phenotype and stemness state but different molecular basis for potential differentiation. Adipogenesis-related genes expression pattern and presence of more mature adipocytes in ADSCs than in LDSCs after 21 days of adipogenic differentiation, indicated that differentiation capacity of LDSCs was significantly lower compared to ADSCs. Analysis of osteogenesis-related markers after 16 days of osteogenic differentiation revealed that both types of cells had characteristic osteoblast-like phenotype, but were at different stages of osteogenesis. Differences observed between LDSCs and ADSCs are probably due to the distinct molecular signature and their commitment in the tissue that governs their different capacity and fate during adipogenic and osteogenic induction in vitro despite their similar mesenchymal phenotype.

Lumbar Intraspinal Osteolipoma Presenting as Cauda Equina Syndrome: A Case Report and Review of Literature

Introduction

Osteolipomas are uncommon variants of lipoma. These lesions have been usually reported to arise from the oral cavity, brain, and neck and scarcely from the knee and thigh. Intraspinal osteolipomas are rare. A single case of intraspinal osteolipoma has been reported in the cervical and thoracic spine in the literature. To our knowledge, there is no report of osteolipomas in the lumbar spine.

Case Presentation

We report a very rare case of a solitary lumbar intraspinal osteolipoma, presenting as a cauda equina syndrome. The intraspinal osteolipoma was excised en bloc and fusion was performed as it required partial resection of the facet joint within 24 hours of presentation. He has since then improved neurologically, and there has been no recurrence of the lesion so far. The clinical presentation, radiological characteristics, treatment course, and histopathological features of this lesion along with the clinical outcomes and a pertinent literature review were done and have been discussed.

Discussion

The heterogeneous signal intensity of the lesion in MRI differentiates it from other dural-based lesions, and this should raise suspicion of an osteolipoma, which warrants a CT. Although intraspinal osteolipomas are benign lesions and generally have good prognosis, they need to be removed en bloc as they may result in rapid neurological deterioration.

Lingual Chondrolipoma in a Dog

A 13-year-old female Yorkshire terrier was presented with difficulty swallowing because of a lingual mass, which had grown to a size of 0.8 × 0.8 × 0.8 cm in 1 month. Grossly, the mass was located in the lingual frenulum and the cut surface was grey-white in colour. Microscopically, the mass was unencapsulated and composed of lobules of mature adipose tissue and cartilaginous tissue with abundant basophilic myxoid matrix separated by fibrous connective tissue. Immunohistochemically, almost all of these cells were positive for vimentin and S100. Chondroid cells and their adjacent spindle cells were also positive for SOX9. Based on these findings, a diagnosis of chondrolipoma was made. To the best of our knowledge, this is the first report of a chondrolipoma originating as a primary tumour in the lingual frenulum of a dog.

Giant Osteolipoma Fixed to the Greater Trochanter of the Femur in a Seventy-Year-Old Elderly Woman

A lipoma containing mature osseous elements is called osteolipoma. This article describes a giant osteolipoma fixed to the periosteum of the greater trochanter of the femur. A seventy-year-old woman presented with a large subcutaneous mass in the right buttock which had been present for six years. On local examination, a giant mass that was ovoid, firm, non-tender, well demarcated, subcutaneous, and relatively fixed to the greater trochanter was palpated in the right buttock. A medical imaging and fluoro-deoxy-glucose (FDG) bone scan revealed a large lipomatous and metabolically active lesion arising from the periosteum of the greater trochanter of femur. The excisional mass of 17 × 8 × 7 cm³ was well encapsulated and had an osseous basal portion. Cut sections of the mass revealed mainly yellow fatty tissue surrounded by a thin fibrous capsule with numerous interlacing thin lamellar bony structures. The definitive pathological diagnosis was osteolipoma without evidence of malignancy. No recurrence was observed at eight months follow-up.

Osteolipoma with an osseous basal portion is rare. Surgical excision is the treatment of choice and the prognosis is good. To the best of our knowledge, this is the first report of an unusual giant osteolipoma fixed to the periosteum of the greater trochanter of the femur.

Cervical paravertebral osteolipoma: case report and literature review

Lipomas are the most frequent soft tissue tumors. Osteolipomas are a rare variant that can be difficult to diagnose. We report the case of a 66-year-old man consulting with a tumor of 2 years development in the right paravertebral cervical region. Neurologically, the patient had no sign of myelopathy or neurological focality. Magnetic resonance imaging showed a mass with a lipid component and calcifications inside within the right paravertebral musculature with a possible origin in the right C3 posterior root. A computed tomography scan and guided biopsy were performed, revealing hematic material and small bone spicules with no apparent neoplastic element. The tumor was totally removed, including the right C3 posterior branch, and was confirmed to be an osteolipoma on biopsy. The patient remains asymptomatic at 6-month follow-up. The osteolipoma is a benign tumor of soft tissue, characterized by lipoma areas with mature bone tissue differentiation, and even with hematopoietic marrow.

Osteochondrolipoma of the submandibular region: a case report and review of the literature

Lipoma is an extremely common and ubiquitous benign soft tissue tumor composed of mature adipose tissue, with frequent differentiation towards other mesenchymal elements such as blood vessels, fibrous tissue, or muscle. They are typically slow-growing, encapsulated, superficial or deep, and have a wide range in size depending on their location. The presence of cartilage or bone is very rare, with most reported cases in the head and neck area. We report the case of an osteochondrolipoma of the submandibular region with associated benign bone marrow elements, with a review of the literature and discussion of the differential diagnosis.

Osteolipoma: radiological, pathological, and cytogenetic analysis of three cases

Osteolipoma is a rare variant of lipoma consisting of mature adipose tissue and mature lamellar bone. The presence of non-fatty elements may lead to a wide differential diagnosis on radiology including benign and malignant lipomatous and nonlipomatous entities. The pathological diagnosis is also confounded by the presence of heterologous differentiation. Fortunately, most lipomas harbor classic cytogenetic aberrations, and the finding of translocations involving 12q13-15 may aid in the correct diagnosis. We report three cases of osteolipoma with radiological, histological, and cytogenetic correlation.

Osteolipoma independent of bone tissue: a case report

Introduction

Lipomas are the most common benign soft tissue tumors and appear in any part of the body. They typically consist of mature adipose tissue. Osteolipoma is an extremely rare histologic variant of lipoma that contains mature lamellar bone within the tumor and osteolipoma independent of bone tissue are very rare. We report a case of histologically confirmed osteolipoma independent of bone located in the thigh.

Case presentation

A 47-year-old male presented with a progressively enlarging, painful mass which approximately 10 cm × 8 cm over the anteromedial aspect of his right thigh. Plain films, Computerized Tomography, Magnetic Resonance Imaging and ultrasound guided needle biopsy were performed. Given the benign imaging characteristics and fine needle aspiration, an excisional biopsy was undertaken. The definitive pathologic diagnosis was intramuscular osteolipoma without evidence of malignancy. No recurrence was observed after 18 months follow up.

Conclusion

Although ossifying lipomas are very rare, it is important to keep them in mind when a lesion with adipose tissue in combination with ossification is encountered.

Giant lipoma of the thenar--case study and contemporary approach to its aetiopathogenicity

Giant lipomas of the thenar are rare tumours of the adipose tissue of the hand, with a benign prognosis. Apart from the cosmetic problems they may cause, their most frequent complications include a compromise in functionality and pressure upon the nerves, mainly on the radial nerve. The first step in their management is their differential diagnosis from well-differentiated liposarcomas (WDLPS), as they require a different therapeutic approach. This step is completed with the aid of MRIs, biopsies and modern immunohistochemical methods, which offer high specificity and sensitivity. Our paper presents a case of giant lipoma of the thenar, with a review of the relevant literature, focusing on the disease's molecular genetics, which is a very important field of research today.

Osteolipoma of the oral and pharyngeal region: report of a case and review of the literature

Osteolipoma is an uncommon phenomenon that rarely occurs in the oral and pharyngeal region. A 68-year-old man presented with a 4-year history of a relatively small painless mass in the right mandibular alveolar mucosa adjacent to the premolar teeth. The lesion was easily excised and histologically confirmed to be an osteolipoma. Ten cases of oral and pharyngeal osteolipoma have appeared in the English literature thus far. In addition to reporting a new case of osteolipoma arising in the oral cavity in this article, the literature is reviewed accordingly.