Differentiated liposarcoma is a rare connective tissue malignancy in adults that mostly occurs in the extremities and retroperitoneum, with a tendency to aggressiveness and recurrence, and the ten-year survival rate of about 10%. Clinically, dedifferentiated liposarcoma of the pharynx has been reported to be rare abroad and only one case has been reported in China. Clinical symptoms are mainly foreign body sensation in the pharynx, which can be easily misdiagnosed as benign tumors. Pathological diagnosis is the main examination tool for this kind of disease, and immunohistochemistry and FISH test can help to differentiate it from other tumors. This article presents a case of a male patient with dedifferentiated liposarcoma of the hypopharynx, who had a foreign body sensation in the pharynx for more than 1 month, and underwent supported laryngoscopic pharyngeal lesion resection after completing the preoperative relevant examinations and postoperative radiation therapy, with postoperative pathology returned as dedifferentiated liposarcoma. The present postoperative follow-up was 12 months without recurrence. Therefore, accurate diagnosis and timely treatment are extremely important for the prognosis of this disease.
Humans ; Male ; Liposarcoma/diagnosis* ; Hypopharyngeal Neoplasms/diagnosis* ; Middle Aged ; Hypopharynx ; Adult

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a patient with De-differentiated liposarcoma (DDLPS). METHODS: A 38-year-old female patient with DDLPS who had visited Hunan Provincial People's Hospital in January 2025 was selected as the study subject. A retrospective study method was adopted to collect the patient's clinical data, including current and past medical history, auxiliary examinations, pathological diagnosis, and results of genetic testing. This study was approved by the Ethics Committee of Hunan Provincial People's Hospital (Ethics No.: KY2025-150). RESULTS: The patient had presented with abdominal pain and abdominal mass. Imaging studies revealed ascites and space-occupying abdominal lesions. Postoperative pathological examination showed that the tumor was composed of spindle cells, and its morphology and immunohistochemistry had made it difficult to distinguish between DDLPS and leiomyosarcoma. High-throughput sequencing revealed characteristic molecular alterations of DDLPS, and fluorescence in situ hybridization confirmed MDM2 gene amplification, leading to a diagnosis of DDLPS. CONCLUSION The patient was diagnosed with DDLPS. Her clinical manifestations and pathological features were consistent with the characteristics of DDLPS. Molecular pathological testing played a crucial role in the diagnosis and provided a crucial reference for subsequent treatment.
Humans ; Female ; Adult ; Liposarcoma/diagnosis* ; Phenotype ; Proto-Oncogene Proteins c-mdm2/genetics*

Liposarcoma is a malignant mesenchymal neoplasm composed of adipose tissue with varying degrees of atypia. While generally indolent, some tumors have the potential to grow enormously particularly if located in the retroperitoneum. We report a 49-year-old female generally asymptomatic except for a 1-year history of gradual abdominal enlargement. Contrast-Enhanced Computed Tomography (CT) of the abdomen showed a large retroperitoneal mass with characteristic features consistent with liposarcoma. On laparotomy, the mass was encapsulated with good plane of dissection, great vessels were preserved, however the right kidney and suprarenal gland were undetachable from the primary tumor hence was removed en bloc with the liposarcoma. The post-operative course was uneventful with excellent outcome after 6 months of follow-up. Final histopathologic diagnosis revealed low-grade, dedifferentiated liposarcoma, which has favorable prognosis following radical surgery.

Retroperitoneal liposarcoma is an uncommon tumor both in the pregnant and nonpregnant state. Its exact incidence is unknown because of its rarity. Due to its propensity for local recurrence, prognosis depends on histologic subtype and negative margins of resection. Surgery remains the mainstay of treatment, and timing is critical in terms of finding a surgically resectable lesion while balancing fetal risks. This report describes tumor recurrence in a pregnancy with a prior history of surgery for an atypical lipomatous tumor presenting as a retroperitoneal mass. After discussion with the multidisciplinary team, as well as with the patient’s consent, the plan was to defer surgery until 34 weeks, followed by scheduled tumor removal 2 weeks postpartum. She delivered abdominally to a baby girl with a good outcome. Histopathology showed dedifferentiated liposarcoma with a positive tumor margin. The patient has survived at 6-month follow-up and completed four cycles of chemotherapy with doxorubicin, ifosfamide, and mesna. However, surveillance imaging again showed tumor recurrence.
Liposarcoma

Humans ; Liposarcoma/surgery* ; Retroperitoneal Neoplasms/surgery* ; Neoplasm Recurrence, Local/surgery*

OBJECTIVE: To investigate the value of using MDM2 amplification probe and DDIT3 dual-color, break-apart rearrangement probe fluorescence in situ hybridization (FISH) technique in the diagnosis of liposarcoma. METHODS: In the study, 62 cases of liposarcoma diagnosed in Peking University First Hospital from January 2015 to December 2019 were analysed for clinicopathological information. Of these 62 cases of liposarcoma, all were analysed for MDM2 amplification and 48 cases were analysed for DDIT3 rearrangement using a FISH technique. Our study aimed to evaluate the status of MDM2 and DDIT3 by FISH in liposarcoma and correlate it with diagnosis of different subtypes of liposarcoma. The subtypes of liposarcoma were classified according to the FISH results, combined with the relevant clinicopathological features. RESULTS: The patients aged 31-89 years (mean: 59 years) with a 1.75:1 male to female ratio. Histologically, there were 20 cases of atypical lipomatous tumour/well-differentiated liposarcoma (ALT/WDLPS), 26 cases of dedifferentiated liposarcoma (DDLPS), 13 myxoid liposarcoma (MLPS) and 3 pleomorphic liposarcoma (PLPS). Tumors with DDLPS (23/26) and WDLPS (8/20) were localized retroperitoneally, while both tumours of MLPS and PLPS were localized extra-retroperitoneally, and the difference of sites among the four subtypes of liposarcoma was statistically significant (P < 0.05). Histologically, varied mucoid matrix could be observed in the four subtypes of liposarcoma, and the difference was statistically significant (P < 0.05). MDM2 gene amplification was demonstrated in all cases of ALT/WDLPS and DDLPS (100%, 20/20 and 26/26 respectively); DDIT3 gene rearrangement was noted only in MLPS (100%, 13/13); most cases of DDLPS (96.2%, 25/26) and ALT/WDLPS (83.3%, 5/6, 6 cases selected for detection) demonstrated the picture of amplification of the DDIT3 telomeric tag. According to the instructions of DDIT3 break-apart rearrangement probe, the 5' telomere probe and 3' centromere probe spanned but did not cover the DDIT3 gene itself, on the contrary, the 5' telomere probe covered the CDK4 gene, while the DDIT3 and CDK4 gene were located adjacent to each other on chromosome, therefore, when the amplification signal appeared on the telomeric tag of the DDIT3 rearrangement probe, it indeed indicated the CDK4 gene amplification rather than the DDIT3 gene rearrangement. Then the 10 cases with DDIT3 telomeric tag amplification were selected for CDK4 and DDIT3 gene amplification probe FISH tests, and all the cases showed CDK4 gene amplification (100%, 10/10) and two of the 10 cases demonstrated co-amplification of CDK4 and DDIT3 (20%, 2/10); DDIT3 polysomy detected by DDIT3 gene rearrangement probe was found in 1 case of DDLPS and 2 cases of PLPS (66.7%, 2/3) with morphology of high-grade malignant tumour and poor prognosis. CONCLUSION Our results indicate that a diagnosis of different subtype liposarcoma could be confirmed based on the application of MDM2 and DDIT3 FISH, combined with clinicopathological findings. It is also noteworthy that atypical signals should be correctly interpreted to guide correct treatment of liposarcomas.
Male ; Female ; Humans ; In Situ Hybridization, Fluorescence/methods* ; Cyclin-Dependent Kinase 4/metabolism* ; Liposarcoma/pathology* ; Lipoma/pathology* ; Gene Amplification ; Transcription Factor CHOP/genetics* ; Proto-Oncogene Proteins c-mdm2/metabolism*

Humans ; Rectum/surgery* ; Liposarcoma/surgery* ; Biomarkers, Tumor

Humans ; Retroperitoneal Neoplasms ; Liposarcoma ; Calcium-Binding Proteins ; Mixed Function Oxygenases ; Membrane Proteins ; Muscle Proteins

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/surgery* ; Retroperitoneal Neoplasms/pathology* ; STAT6 Transcription Factor