Objective: To investigate the clinicopathologic and molecular genetic characteristics of myxoid pleomorphic liposarcoma (MPLPS). Methods: Six cases of MPLPS diagnosed and consulted in Fujian Provincial Hospital from 2015 to 2021 were collected for histomorphological observation, immunohistochemistry, and fluorescence in situ hybridization (FISH) detection of DDIT3 (CHOP) gene translocation and MDM2/CDK4 gene amplification. Results: There were four males and two females, aged 26-74 years (mean 53.8 years). The tumor size was 3.8-16.0 cm (mean 11.8 cm). All six cases had similar histopathologic features, showing overlapping histologic morphology of myxoid liposarcoma and pleomorphic liposarcoma. Four cases (4/6) were positive for S-100 protein, and the Ki-67 index was 50%-95%. All cases (6/6) were negative for DDIT3 (CHOP) translocation and MDM2/CDK4 amplification by FISH. TP53 (p.R248w) germline mutation was found in one case. Conclusions: MPLPS is a rare subtype of liposarcoma, characterized by overlapping morphology of myxoid liposarcoma and pleomorphic liposarcoma. Genetically, a few of them have TP53 gene germline mutations, but they lack of DDIT3 (CHOP) translocation or MDM2/CDK4 amplification.
Female ; Humans ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Liposarcoma/pathology* ; Liposarcoma, Myxoid/diagnosis* ; Male ; Molecular Biology ; Proto-Oncogene Proteins c-mdm2/genetics* ; Translocation, Genetic

Humans ; Liposarcoma/genetics* ; Liposarcoma, Myxoid/genetics* ; Transcription Factor CHOP/genetics*

PURPOSE: The purpose of this study was to characterize and evaluate the clinical significance of volume changes of soft tissue sarcomas during radiation therapy (RT), prior to definitive surgical resection. MATERIALS AND METHODS: Patients with extremity or pelvis soft tissue sarcomas treated at our institution from 2013 to 2016 with RT prior to resection were identified retrospectively. Tumor volumes were measured using cone-beam computed tomography obtained daily during RT. Linear regression evaluated the linearity of volume changes. Kruskal-Wallis tests, Mann-Whitney U tests, and linear regression evaluated predictors of volume change. Logistic and Cox regression evaluated volume change as a predictor of resection margin status, histologic treatment response, and tumor recurrence. RESULTS: Thirty-three patients were evaluated. Twenty-nine tumors were high grade. Prior to RT, median tumor volume was 189 mL (range, 7.2 to 4,885 mL). Sixteen tumors demonstrated significant linear volume changes during RT. Of these, 5 tumors increased and 11 decreased in volume. Myxoid liposarcoma (n = 5, 15%) predicted decreasing tumor volume (p = 0.0002). Sequential chemoradiation (n = 4, 12%) predicted increasing tumor volume (p = 0.008) and corresponded to longer times from diagnosis to RT (p = 0.01). Resection margins were positive in three cases. Five patients experienced local recurrence, and 7 experienced distant recurrence, at median 8.9 and 6.9 months post-resection, respectively. Volume changes did not predict resection margin status, local recurrence, or distant recurrence. CONCLUSION: Volume changes of pelvis and extremity soft tissue sarcomas followed linear trends during RT. Volume changes reflected histologic subtype and treatment characteristics but did not predict margin status or recurrence after resection.
Cone-Beam Computed Tomography ; Diagnosis ; Extremities ; Humans ; Linear Models ; Liposarcoma, Myxoid ; Pelvis ; Recurrence ; Retrospective Studies ; Sarcoma ; Tumor Burden

PURPOSE: This study assessed the treatment outcomes of myxoid liposarcoma in the extremities and investigate the prognostic factors. MATERIALS AND METHODS: A total of 91 patients with myxoid liposarcoma (83 primary, 8 recurrent) between 2001 and 2015 were reviewed retrospectively. The local recurrence and metastasis after treatment were examined. The survival rates and prognostic factors affecting the survival were investigated. The mean follow-up was 84 months (range, 5–196 months). RESULTS: The overall survival rates at 5-yr and 10-yr were 82% and 74%, respectively. The tumor size (p=0.04), round cell component (p<0.0001), grade (p=0.0002), and local recurrence (p=0.006) affected survival in primary patients. Extrapulmonary metastases were observed in 75.0% (18/24) of metastatic patients and the mean post metastasis survival was 26 months (range, 2–72 months). CONCLUSION: Myxoid liposarcoma developed mainly at the lower extremities. The tumor size, grade, component of round cells, and local recurrence were associated with the prognosis. The unique feature of extrapulmonary metastasis in myxoid liposarcoma should be noted in the treatment and follow-up.
Cellular Structures ; Extremities ; Follow-Up Studies ; Humans ; Liposarcoma ; Liposarcoma, Myxoid ; Lower Extremity ; Neoplasm Metastasis ; Prognosis ; Recurrence ; Retrospective Studies ; Survival Rate

Myxoid liposarcoma arose from the spermatic cord is very rare. Also, it is difficult to diagnose by clinical findings or radiologic study. Even if it was a malignant tumor, scrotal malignancy is often misdiagnosed in many cases. A 55-year-old man presented with a mass in the left scrotum. Tumor markers showed all normal range. A scrotal magnetic resonance imaging scan revealed a vascular tumor such as a hemangioma. But, we performed radical orchiectomy. The mass was diagnosed as paratesticular myxoid liposarcoma. It is important to keep in mind the differential diagnosis of paratesticular liposarcoma in the case of a painless scrotal tumor.
Biomarkers, Tumor ; Diagnosis, Differential ; Hemangioma ; Humans ; Liposarcoma ; Liposarcoma, Myxoid ; Magnetic Resonance Imaging ; Middle Aged ; Orchiectomy ; Reference Values ; Scrotum ; Spermatic Cord

Primary mesenteric liposarcoma is rare. It is difficult to make an accurate preoperative diagnosis of the myxoid type of liposarcoma by using imaging such as ultrasound or computed tomography (CT) due to the very small amount of fat that is located in the tumor. We report a case of primary myxoid liposarcoma of the mesentery which was difficult to differentiate from other solid mesenteric tumors with a myxoid component such as low grade fibromyxoid sarcoma, myxoid leiomyosarcoma or myxoma. Use of chemical shift magnetic resonance (MR) imaging to detect small fat components and its cystic appearance with solid components on the MR images can be useful to differentiate myxoid liposarcoma from the other mesenteric tumors with a myxoid component.
Diagnosis ; Leiomyosarcoma ; Liposarcoma ; Liposarcoma, Myxoid* ; Magnetic Resonance Imaging ; Mesentery* ; Myxoma ; Sarcoma ; Ultrasonography

Primary liposarcomas constitute less than 1% of all mediastinal tumors. The posterior mediastinum is the location in 95% of cases. Literature search did not show a case that encompassed three mediastinal compartments.
A 32-year old man was diagnosed with high grade primary mediastinal liposarcoma (80% myxoid plus 20% round cell), after presenting with superior vena cava syndrome. CT-scan revealed lobulated masses on the superior, anterior, and the right middle mediastinum measuring 7.8 x 9.0 x 7.5 cm and compressing the superior vena cava. He underwent surgical debulking and palliative 3 cycles doxorubicin-based chemotherapy, but later succumbed to pneumonia.

Human ; Male ; Adult ; Liposarcoma ; Mediastinum ; Vena Cava, Superior ; Myxoid ; Doxorubicin ; Pneumonia

The pathological features of a mass in the back skin region of an 8-year-old castrated male dog are described herein. The cut section of the tumor was white to tan with a soft multilobulated mass containing hemorrhagic and necrotic foci and a mucinous-like composition. Microscopically, the tumor was composed of a mixture of lipocytes, lipoblasts, spindle cells and stellate cells and had a myxoid background. Oil red O staining revealed that the cytoplasm of neoplastic cells contained large numbers of lipid droplets. Immunohistochemically, tumor cells were positive for vimentin and S-100 protein. The skin mass was diagnosed as myxoid liposarcoma.
Adipocytes ; Animals ; Child ; Cytoplasm ; Dogs* ; Humans ; Liposarcoma, Myxoid* ; Male ; S100 Proteins ; Skin ; Triacetoneamine-N-Oxyl ; Vimentin

OBJECTIVETo study the diagnostic value and pitfalls of ultrasound-guided core needle biopsy (CNB) of soft tissue tumors.

METHODSOne hundred and six cases of CNB specimens encountered during the period from 2007 to 2012 were enrolled into the study. The pathologic diagnosis using CNB was compared with that using surgical specimens. Diagnostic accuracy was analyzed using Chi-square test, with respect to the histologic pattern (such as spindle cell and myxoid), biologic behavior (benign versus malignant) and immunohistochemical results. The 59 cases of sarcoma were subdivided into three grades according to FNCLCC grading system.

RESULTSHistologic diagnosis could be made in 84.0% (89/106) cases. Thirteen cases were non-diagnostic on CNB. There were 4 cases on CNB showing diagnostic discrepancy with surgical specimens. Four cases of "benign lesions" on CNB found to be myxoid liposarcoma and lipoma-like liposarcoma upon resection. In general, myxoid pattern (9/17) seen on CNB showed less diagnostic correlation with surgical specimens, as compared to spindle cell and other histologic patterns (P < 0.01). The rate of diagnostic correlation was 79.7% (49/59) for the 59 cases of sarcoma studied, with grade 2 and grade 3 sarcoma showing better correlation (in contrast to 7/17 for grade 1 sarcoma) (P < 0.01). Comparative analysis showed no significant difference between benign/borderline tumors and sarcomas. The application of immunohistochemical study did not result in significant improvement in diagnostic accuracy on CNB.

CONCLUSIONSUltrasound-guided CNB is a reliable tool in pathologic diagnosis of soft tissue tumors and shows a high accuracy rate especially for high-grade sarcoma. Tumors with myxoid pattern, lipomatous tumors and grade 1 sarcomas are associated with lower diagnostic accuracy on CNB. Correlation with clinicoradiologic findings would also be helpful in diagnostic evaluation and surgical planning.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Biopsy, Large-Core Needle ; methods ; Diagnostic Errors ; Extremities ; Female ; Humans ; Liposarcoma, Myxoid ; diagnosis ; diagnostic imaging ; pathology ; Male ; Middle Aged ; Neoplasm Grading ; Sarcoma ; diagnosis ; diagnostic imaging ; pathology ; Soft Tissue Neoplasms ; diagnosis ; diagnostic imaging ; pathology ; Ultrasonography, Interventional ; methods ; Young Adult

Cranial Fossa, Anterior ; Humans ; Liposarcoma, Myxoid ; diagnostic imaging ; metabolism ; pathology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; S100 Proteins ; metabolism ; Skull Base Neoplasms ; diagnostic imaging ; metabolism ; pathology ; Tomography, X-Ray Computed