Histology image of a soft tissue mass showing features diagnostic of myxoid liposarcoma, high-grade (round cell) variant. The specimen is a tissue biopsy examined by light microscopy after Hematoxylin and Eosin staining. The architectural pattern reveals a prominent myxoid (mucoid) extracellular matrix with a delicate, arborizing capillary network radiating from vessels, a classic backdrop for myxoid adipocytic tumors. Intermixed are primitive, round to oval tumor cells arranged in cords and short trabeculae extending from the vascular core. The cells have scant cytoplasm, hyperchromatic nuclei, and mitotic activity is variably increased consistent with high-grade transformation. Occasional lipoblasts with scalloped cytoplasm may be present, highlighting adipocytic differentiation amidst the myxoid milieu. The surrounding stroma is relatively cellular in the high-grade areas, with less prominent lipogenic features compared with low-grade components. This image emphasizes the cellularity and architectural disruption associated with the round cell component, which portends a more aggressive clinical behavior and higher metastatic potential. Clinically, identification of high-grade cell populations in a predominantly myxoid liposarcoma influences prognosis and treatment planning, including surgical excision with wide margins and consideration of adjuvant chemotherapy or radiotherapy. Overall, the image exemplifies hallmarks used in pathology reports to classify liposarcoma subtype and grade for diagnostic accuracy.

Gross pathology photograph of a myxoid liposarcoma in a soft-tissue tumor specimen. Modality: gross examination with photographic documentation. The specimen is a well-circumscribed soft mass, measuring roughly 8–9 cm in greatest dimension, with a glistening, gelatinous cut surface that reflects abundant myxoid extracellular matrix. The exterior is tan-pink and slightly translucent, with a lobulated contour and a moist, glossy surface. The cut surface reveals a homogeneous, mucinous pale-yellow to pinkish material interspersed with sparse adipose elements; there may be minor hemorrhagic foci at the periphery. The margins appear relatively well defined in the specimen, though in vivo growth can be infiltrative. Overall, the gross morphology is consistent with myxoid liposarcoma, a malignant adipocytic tumor characterized by a plentiful myxoid stroma and delicate capillary networks. This gross pattern correlates with the characteristic histology of myxoid liposarcoma: abundant myxoid stroma containing delicate capillaries and scattered lipoblasts at the microscopic level. Clinically, recognizing this gross pattern aids in prompt pathologic triage, surgical planning, and prognosis. This image is valuable for education in soft tissue sarcomas, tumor grossing technique, and radiopathology correlation, and it supports teaching datasets and searchable image repositories for pathology training, case-based learning, and medical informatics. Educational value assured.

This composite figure illustrates the clinical management and pathology of a primary myxoid liposarcoma in the left thigh of a 20-year-old male. (A-C) Diagnostic MRI in coronal and axial planes shows a large, hyperintense, well-circumscribed ovoid mass within the medial muscle compartment. A yellow dotted line in (C) indicates the planned surgical margins. (D) A biopsy sample on gauze confirms the preoperative diagnosis. (E-F) Surgical progression images depict the planned incision incorporating the biopsy site and the intraoperative field where periosteal resection was performed near the bone. (G-H) Macroscopic pathology of the resected specimen reveals a smooth, glistening, reddish-brown encapsulated mass. Longitudinal sectioning (H) demonstrates a heterogeneous internal architecture with prominent dark regions of central necrosis and cystic degeneration, characteristic of high-grade components or typical evolution of large liposarcomas. The sequence highlights the workflow from diagnostic radiology and biopsy to wide surgical excision and gross pathological assessment in musculoskeletal oncology.

This histopathology image depicts a relatively cellular area within a myxoid liposarcoma on Hematoxylin and Eosin staining using bright-field light microscopy. The tumor is embedded in a prominent myxoid (mucinous) extracellular matrix, rendered in pale bluish-purple, with a delicate, arborizing capillary vascular network that is characteristic of this entity. Scattered lipoblasts are present, identified by cytoplasmic lipid vacuoles that indent (scallop) the nuclei, and by occasional hyperchromatic, rounded to oval nuclei. The neoplastic cells range from small to moderately sized spindle- to stellate-shaped cells with variably eosinophilic, scant cytoplasm and mild nuclear atypia. Cellular areas show increased density compared with the abundant myxoid background. Mitotic figures are uncommon in this field, and there is no conspicuous necrosis. The overall pattern—myxoid stroma with a plexiform capillary network and lipogenic cells—supports a diagnosis of myxoid liposarcoma; higher cellularity regions can be encountered in the cellular variant. This histology distinguishes from other lipomatous neoplasms and from other myxoid sarcomas by the presence of lipoblasts and the characteristic branching vasculature. Clinically, dx is often reinforced by molecular tests for DDIT3 gene rearrangement. Correlate with imaging (MRI/CT) and clinical presentation for staging and treatment planning.

Imaging modality: Light microscopy of hematoxylin-eosin stained histology section from a soft tissue biopsy containing a liposarcoma with prominent myxoid matrix. Anatomical context: soft tissue tumor, unspecified site, intratumoral myxoid stroma with mucin pooling. Visual features: abundant mucin pools create cribriform or lacelike architecture; flat tumor cells line mucin pools with intermittent rounded cells at the pool rims; pseudoacinar patterns arise at the mucin borders; in some areas, a lymphangioma-like appearance is observed; occasional cystic spaces and edema-like basophilic mucin mimic pulmonary edema histology. These features are typical of myxoid liposarcoma; adipocytic differentiation may be seen; scattered delicate capillary networks may accompany the mucin pools. This histology supports diagnosis of myxoid liposarcoma, a soft tissue sarcoma characterized by abundant myxoid stroma and a plexiform capillary network; the mucin-rich milieu contributes to a clear-to-pale appearance on H&E. Diagnostic significance: recognition of myxoid matrix with pooling mucin and cribiform pattern aids distinction from myxofibrosarcoma and other myxoid sarcomas; differential diagnoses include myxoid chondrosarcoma or metastatic mucinous carcinoma depending on location. Clinical correlation: correlate with tumor size, site, and imaging (MRI features of high T2 signal with heterogenous enhancement); prognosis varies with histologic grade and presence of lipoblasts. Potential clinical use cases include diagnostic confirmation and educational illustration for soft-tissue pathology.

Histopathology image depicts a high-grade myxoid liposarcoma, round cell predominant. Using light microscopy, sections stained with hematoxylin and eosin show primitive-appearing tumor cells arranged in cords, nests, and short trabeculae within a variably myxoid matrix. The tumor displays a delicate, plexiform capillary network typical of myxoid liposarcoma, with prominent branching, thin-walled vessels in a myxoid stroma. Cells are small to medium-sized with hyperchromatic, elongated to round nuclei, scant cytoplasm, and conspicuous mitotic activity in high-grade areas. Occasional lipoblast-like cells may be seen; lipogenic differentiation is variably evident. The background myxoid stroma appears pale pink to blue with abundant mucopolysaccharide matrix. Necrosis is minimal or focal. The lesion lacks overt adipocytic maturation in the high-grade component. Immunohistochemistry is not provided in image, but typical profiles show variable S-100 positivity; molecular hallmark is the FUS-DDIT3 fusion gene due to t(12;16)(q13;p11). Clinically, this histology portends a higher risk of metastasis and recurrence compared to conventional, low-grade myxoid liposarcoma. Potential differential diagnoses include round cell variants of other soft tissue sarcomas such as synovial sarcoma, Ewing/PNET, and malignant peripheral nerve sheath tumor, requiring molecular testing to confirm. The image is educational for pathology education, tumor histology, and diagnostic pathology training; relevant for surgical oncology planning and radiation therapy decisions.