Well-differentiated Liposarcoma Research Articles

Another Addition to Abdomen’s Pandora’s Box: Multi-compartment Enormous Liposarcoma

Abstract Soft tissue sarcomas constitute less than 1% of all neoplasms, with a third of malignant tumours in the retroperitoneum being sarcomas and liposarcoma being the commonest. Local aggressiveness and clinical non-specificity make treatment challenging. A 52-year-old man presented with a massive lump in the abdomen. Surgery following work-up indicated a well-differentiated retroperitoneal liposarcoma (RPLS) with intraperitoneal and scrotal extension and weighed a substantial 6.8 kg. Treatment required meticulous local resection preserving the functionality. RPLS manifests as a large, locally advanced lesion with intraperitoneal extension, but extension into the inguinal canal is unknown. Being low grade, distant metastasis is infrequent, and the challenge lies in achieving effective local control and preventing local recurrence. The preferred treatment involves radical resection incorporating en bloc resection of involved structures. Strategic neoadjuvant and adjuvant therapies, tailored to specific tumour histology, may enhance local control and overall survival. Radical resection of the tumour from the mesentery of the large and small bowel, preserving their vascularity along with retroperitoneal component, albeit in parts, was achieved and is the first-line cure in RPLS. In select cases, individualised chemotherapy and radiation therapy may offer a survival benefit.

Clinico-Radiological-Pathological Correlation in a Rapidly Evolving Well-Differentiated Orbital Liposarcoma: A Case Report

Clinico-Radiological-Pathological Correlation in a Rapidly Evolving Well-Differentiated Orbital Liposarcoma: A Case Report

Giant Well-Differentiated Liposarcoma of Esophagus Completely Removed by Endoscopic Submucosal Dissection.

Giant Well-Differentiated Liposarcoma of Esophagus Completely Removed by Endoscopic Submucosal Dissection.

Survival and prognostic factors among different types of liposarcomas based on SEER database

The aim of this study is to elucidate the disparities in survival and risk factors among different subtypes of liposarcoma, through analysis of epidemiological and prognostic data. The study cohort consisted of 12,822 patients diagnosed with liposarcoma in the United States between 2000 and 2021, whose data were retrieved from the Surveillance, Epidemiology, and End Results (SEER) program. The prognosis for different subtypes of liposarcoma and the associated factors such as age, tumor stage, intervention, gender, tumor grade, location, size, chemotherapy and radiotherapy, were retrieved from the database. Well-differentiated liposarcoma demonstrated the most favorable prognosis, with 5-year and 10-year survival rates of 82% and 68%, respectively, followed by myxoid liposarcoma, pleomorphic liposarcoma and dedifferentiated liposarcoma, which exhibited the poorest prognosis. Advanced age, higher tumor stage, and the absence of surgical intervention were associated with inferior survival outcomes across all subtypes. Male gender, higher pathological grade, and primary tumor sites outside the extremities were identified as risk factors for the prognosis of subtypes other than pleomorphic liposarcoma. Larger tumor size was an indicator of a worse prognosis in subtypes other than well-differentiated liposarcoma. Chemotherapy was a risk factor for the prognosis of well-differentiated and myxoid liposarcomas but had no significant correlation with the prognosis of pleomorphic and dedifferentiated liposarcomas. Radiotherapy served as a protective factor for the prognosis of subtypes other than well-differentiated liposarcoma. Survival and prognostic factors vary among the major subtypes of liposarcoma, necessitating individualized analysis for each subtype. Poorer outcomes can be anticipated in the dedifferentiated and pleomorphic subtypes, while well-differentiated and myxoid liposarcomas exhibit relatively favorable prognoses.

NTRK amplification occurs frequently in pan-TRK immunopositive dedifferentiated liposarcomas.

The neurotrophic tyrosine kinase receptor (NTRK) gene family is of rising importance as their fusions are oncogenic, and specific target drugs are available to inhibit the chimera proteins. Pan-TRK antibody, which shows the overexpression of the NTRK1-2-3 genes, is a useful tool to detect tumors with or without NTRK gene alterations, due to high negative predictive value. Though it is well known that pan-TRK immunopositivity is usually not connected to NTRK fusion, the role of other possible genetic alterations is under-researched. In our previous work, we found 3 NTRK1 amplified cases out of 6 cases with recurrent NTRK1 tyrosine kinase domain mutation pair, so we extended our investigation to a larger series to estimate amplification frequency. Pan-TRK immunopositivity was seen in 76 of the 132 dedifferentiated liposarcomas cases, followed by NTRK1-2-3 break-apart FISH tests in 76 pan-TRK positive cases to detect oncogenic fusions or other copy number alterations of these genes. None of the pan-TRK immunopositive dedifferentiated liposarcomas showed absolutely certain sign of fusion, however, 18 (28%) cases showed amplification of one of the genes, 13 had polysomy, 34 were normal, 11 were not evaluable. The extent of pan-TRK immunoreaction showed a positive correlation (p = 0.002) with the NTRK status found by FISH. Analyzing publicly available data from large series of 265 liposarcoma samples consisting of both well-differentiated and dedifferentiated liposarcoma case, 23 (8.6%) cases showed a mutual exclusive amplification of the NTRK genomic loci in a non-preselected, independent patient population indicating that our findings are presented in other cohorts. Our results underline the so far not revealed frequent occurrence of NTRK amplifications which might be important in the TRK inhibition therapy.

Revisiting a soft tissue pathology heresy: a clinicopathological study of 17 retroperitoneal lipomas (with comparison to well-differentiated liposarcoma)

Revisiting a soft tissue pathology heresy: a clinicopathological study of 17 retroperitoneal lipomas (with comparison to well-differentiated liposarcoma)

Integrated lipidomics and RNA-seq reveal prognostic biomarkers in well-differentiated and dedifferentiated retroperitoneal liposarcoma

BackgroundRetroperitoneal liposarcoma (RLPS) is a mesenchymal malignant tumor characterized by different degrees of adipocytic differentiation. Well-differentiated liposarcoma (WDLPS) and dedifferentiated liposarcoma (DDLPS) are two of the most common subtypes of RLPS, exhibiting clear differences in biological behaviors and clinical prognosis. The metabolic features and genomic characteristics remain unclear.MethodsThis study employed lipidomic and RNA-seq analyses of RLPS tissues from 19 WDLPS and 29 DDLPS patients. Western blot and immunohistochemistry staining were performed to verify the tumor tissue protein levels of TIMP1, FN1, MMP11, GPNMB, and ECM1. Enzyme-linked immunosorbent assay (ELISA) was performed to evaluate different serum protein levels in 128 blood samples from patients with RLPS. Multivariate analysis was performed to identify the most crucial variables associated with overall survival (OS) and recurrence-free survival (RFS) of the RLPS patients.ResultsLipidomic analysis revealed a significant difference in lipid metabolism, particularly in phosphatidylcholines and triacylglycerides metabolism. RNA sequencing analysis revealed that 1,630 differentially expressed genes (DEGs) were significantly enriched in lipid metabolism, developmental process, and extracellular matrix (ECM) pathways. Integrated lipidomic and transcriptomic analysis identified 29 genes as potential biomarkers between WDLPS and DDLPS. Among the 29 DEGs, we found that TIMP1, FN1, MMP11, GPNMB, and ECM1 were increased in DDLPS tumor tissues than in WDLPS tumor tissues. The receiver operating characteristic (ROC) curve showed high specificity and sensitivity in diagnosing patients using a five-gene combination (AUC = 0.904). ELISA revealed a significant increase in the serum levels of ECM1 and GPNMB in patients with DDLPS compared to patients with WDLPS. ECM1 increased progressively across different FNCLCC Grades, correlating negatively with RFS (P = 0.043). GPNMB levels showed a negative correlation with OS (P = 0.019).ConclusionsOur study reveals different lipid metabolism, several transcriptional pathways between WDLPS and DDLPS, and examines several serum markers associated with the prognosis of RLPS. These findings provide a vital basis for future endeavors in diagnosing and predicting the prognosis of retroperitoneal liposarcoma with different differentiations.

Targeted transcriptomic analysis of well-differentiated and dedifferentiated liposarcoma reveals multiple dysregulated pathways including glucose metabolism, TGF-β, and HIF-1 signaling.

Liposarcoma is the most prevalent sarcoma in adults representing 20% of all sarcomas with well-differentiated/dedifferentiated among the most common subtypes represented. Despite multimodality treatment approaches, there has not been any appreciable change in survival benefit in the past 10 years. The future of targeted therapy for WD/DDLPS is promising with the intention to spare multi-visceral removal due to radical surgical resection. Therefore, there is a need to expand upon the molecular landscape of WDLPS and DDLPS which can help identify potential therapeutic targets for the treatment of this disease. Targeted transcriptome analysis using the NanoString tumor signaling 360 panel revealed a dysregulation in glucose metabolism and HIF1 signaling pathways in both WDLPS and DDLPS when compared to normal fat controls. WDLPS, however, demonstrated upregulation of HIF-1A and TGF-β when compared to DDLPS by targeted transcriptome analysis and orthogonal validation by RT-qPCR suggesting activation of EMT pathway in WDLPS when compared to DDLPS. Our findings implicate a putative role for dysregulation in glucose metabolism, TGF-β and HIF1 signaling in the pathogenesis of both WD/DDLPS suggesting a possible proinflammatory tumor environment within WDLPS and subsequent activation of the TGF-β signaling pathway.

Liposarcoma: A Journey into a Rare Tumor's Epidemiology, Diagnosis, Pathophysiology, and Limitations of Current Therapies.

Sarcomas are a heterogeneous group of neoplasms that develop from bone and soft tissue. Approximately 80% of sarcomas affect soft tissue, with liposarcoma being one of the most common types, accounting for approximately 13-20% of all soft-tissue sarcomas. Per the World Health Organization, liposarcoma can be broadly classified into four different subtypes based on histologic examination: well-differentiated liposarcoma (WDLS)/atypical lipomatous tumors (ALT), dedifferentiated liposarcoma (DDLS), myxoid liposarcoma (MLS), and pleomorphic liposarcoma (PLS). WDLS/ALT is the most common liposarcoma subtype, accounting for approximately 31-33% of liposarcomas; DDLS accounts for 20%; MLS accounts for 19%; and PLS, the least common subtype, represents 7-8% of liposarcomas. Sarcoma diagnosis is challenging because of its rarity, intrinsic complexity, and diagnostic technological complexity. Sarcomas are misdiagnosed in approximately 30% of cases, leading to delays in diagnosis and access to appropriate therapy and clinical trials. Furthermore, treatment options are limited for those diagnosed with liposarcoma. This review discusses the epidemiology, pathology, and treatment options currently available for liposarcoma.

Primary Liposarcoma of the Spleen: Case Report With Review of the Literature.

We present a 55-year-old woman with a palpable mass in the right upper abdomen. Contrast-enhanced computed tomography showed a highly vascularized and primary resectable tumor of the spleen. We performed an open splenectomy with locoregional lymphadenectomy. Histopathological and immunohistochemical evaluation did not reveal classic markers of angiosarcoma, littoral cell angioma, or follicular dendritic cell sarcoma, but showed MDM2-amplification by FISH in all tumor cells as a marker for liposarcoma. The tumor showed growth limited to the spleen tissue. No MDM2-amplification was detectable in the perisplenic adipose tissue, so that infiltration of the spleen by retroperitoneal liposarcoma could be excluded. In summary, well-differentiated liposarcoma confined to the spleen was diagnosed. To the best of our knowledge, this is the first description of a primary liposarcoma of the spleen reported in the literature. Due to the local recurrence risk of liposarcomas, even after R0 resection, we recommended long-term periodic follow-up.

Perinephric myxoid pseudotumor of fat: A series of 13 cases and literature review

Perinephric myxoid pseudotumor of fat (PMPF) is a recently described and rare retroperitoneal mass-forming lesion whose clinical significance chiefly involves mimicry of a variety of soft tissue tumors. For unknown reasons, it commonly occurs in male patients with underlying non-neoplastic renal diseases and/or type 2 diabetes (DMT2). A total of 55 cases have been reported in the literature. Recently, we have encountered 13 such masses with peculiar histologic features; thus, we sought to investigate our experience and review the clinicopathologic characteristics of the literature. Our series confirms that PMPF frequently occurs in adult male patients (11/13, 85%), with an average age of 66 years, and commonly co-occurs with renal disease, such as DMT2 (2/13, 15%), end-stage renal disease (ESRD) (5/13, 39%), renal cysts (4/13, 31%), concurrent or prior renal neoplasia (2/13; 15%), and myeloma/lymphoma (2/13; 15%). Histologic evaluation shows lipomatous masses commonly showing variable amounts of fat necrosis, myxoid degeneration, lymphoplasmacytic inflammation and lacking atypical hyperchromatic stromal spindle cells. Unusual histologic features include extramedullary hematopoiesis (1/13, 8%), hemosiderin deposition (4/13, 31%), and small wisps of mature smooth muscle (6/13, 46%). All cases tested were negative for MDM2 and did not show an increased ratio of IgG4+/IgG+ plasma cells. Our study confirms the clinical and pathologic features of PMPF and expands its histologic spectrum, underscoring the importance of this entity as a benign pseudotumor which should be included in the differential diagnosis of other fat-containing retroperitoneal masses, particularly well-differentiated liposarcoma.

Real-world Referral Pattern of Unplanned Excision in Patients With Soft-tissue Sarcoma: A Multicenter Study Conducted by the Bone and Soft-tissue Tumor Study Group of the Japan Clinical Oncology Group.

Despite the well-publicized clinical outcomes after unplanned excision (UE) and re-excision (re-excision) in patients with soft-tissue sarcoma (STS), there is little information about the real-life referral patterns for UE, such as patient profile, details of procedures, and subsequent management after UE. We aimed to investigate the characteristics of patients with UE who were referred to sarcoma-specific centers. Between May 2022 and June 2023, we registered 97 patients who underwent UE and were referred to sarcoma-specific centers in Japan. We excluded those with well-differentiated liposarcomas and dermatofibrosarcoma protuberances. We investigated the details of UE and additional treatment after UE. There were 49 men and 48 women, with a mean age of 62 years. A broad range of surgeons performed UE; 36 plastic surgeons, 22 orthopedic surgeons, 17 general surgeons, 17 dermatologists, and 5 others. The mean tumor size was 4.1 cm. Local anesthesia was administered to 58 patients. Forty-five patients underwent UE without prior magnetic resonance imaging. Inappropriate transverse skin incisions were performed in 42 patients. Of the 97 patients, 82 underwent re-excision after UE. The mean time between UE and date of initial presentation at the referral hospital was 46 days. The mean interval between UE and re-excision was 96 days. Of the 82 patients, 59 underwent soft-tissue reconstruction after re-excision. A broad range of surgeons performed UE. Continuous education about STS should be considered for all surgeons. UE should be avoided because residual tumors are common, and reconstructive surgery may be necessary.

Evaluation of morphological patterns and immunohistochemical characteristics of well-differentiated and dedifferentiated liposarcomas

Bevezetés: A liposarcomák morfológiailag változatos csoportot alkotnak a mesenchymalis malignitások között. A lágyrész-daganatok diagnosztikája során mindig fel kell merülnie a jól differenciált és a dedifferenciált liposarcoma lehetőségének. E daganatok eddigi legmegbízhatóbb immunhisztokémiai markere az MDM2 volt, a liposarcomák azonban más markerekkel is sokféle pozitivitást mutathatnak. Módszer: Tanulmányunkban a Szegedi Tudományegyetemen ismételten áttekintettük a 2017 és 2022 között előfordult, jól és dedifferenciált liposarcomás eseteket, és szükség esetén további immunhisztokémiai vizsgálatokat végeztünk, beleértve az MDM2-, CDK4-, p16- és STAT6-vizsgálatot. Eredmények: Kohorszunkban 7 esetben fordult elő jól differenciált, 11 esetben pedig dedifferenciált liposarcoma. Minden morfológiai mintázatot regisztráltunk és lefényképeztünk. Az esetek több mint felében a tumor a retroperitoneumban helyezkedett el (n = 11), és 8 betegnél T4-es stádiumban jelentkezett. Az MDM2 minden esetben fokálisan vagy diffúzan pozitív volt (n = 18), míg a CDK4 és a p16 szinte minden esetben diffúzan pozitívnak bizonyult (n = 17). A morfológiai változatosság ellenére az összes dedifferenciált liposarcoma (n = 11) pozitív volt MDM2-, CDK4- és p16-reakcióval is. A STAT6 3 dedifferenciált liposarcomás esetben mutatott multifokális nukleáris pozitivitást. Következtetés: A liposarcoma diagnózisának felállításához MDM2, CDK4 és p16 immunhisztokémiai reakciókat, valamint MDM2 fluoreszcens in situ hibridizációt szükséges végezni. Dedifferenciált liposarcomás eseteink jelentős kisebbsége mutatott multifokális pozitivitást a STAT6-tal, ezért a solitaer fibrosus tumorokból származó kis mintáknál az MDM2-reakció elvégzése ajánlott a liposarcoma lehetőségének kizárására. Tanulmányunk az első, amely a liposarcomák valamennyi jól ismert morfológiai mintázatát tartalmazza. Orv Hetil. 2024; 165(43): 1700–1706.

MDM2 Testing In Lipomatous Tumors: An Institutional Experience with 1,161 Neoplasms

Abstract Introduction/Objective Amplifications of the MDM2 gene is a well-recognized central molecular event in atypical lipomatous tumors, well-differentiated liposarcomas, and dedifferentiated liposarcomas. However, given the fact that most adipocytic neoplasms are benign, the specific testing approaches that will maximize the detection of MDM2 amplified tumors in an accurate and cost-efficient manner remains unclear. The purpose of this study is to present our experience with MDM2 testing by FISH in a large cohort of lipomatous neoplasms. Methods/Case Report The pathologic database of an academic medical center was queried for all lipomatous tumors as well as all tumors for which MDM2 testing was performed during a three-year period. At our center, MDM2 testing for well differentiated adipocytic neoplasms is triggered by the so-called “traditional criteria”: a deep tumor and/or tumor size >10 cm and/or recurrence. We also take an expanded approach for a variety of indications that may include equivocal atypia or clinical/imaging concern, among others. Testing is also performed on overt malignancies for which dedifferentiated liposarcoma is a plausible consideration after review of morphologic features. Clinicopathologic data, including patient age of diagnosis, tumor size, depth of tumor, results from MDM2 testing [when performed], anatomic location(s) and recurrence [where applicable], were collected for each patient. Results (if a Case Study enter NA) 1161 cases were assessed, 456 of whom underwent MDM2 testing, and 108 of which were ultimately classified as MDM2 amplified. Standardized bivariable comparisons found that a deep tumor location (p=0.0014) and older age (p=0.0002), but not tumor size at the >10 cm cut off were associated with MDM2 positivity. However, a logistic regression model showed that neither size, depth or age were significantly associated with MDM2 positivity. Among the MDM2-positive cohort, 91% had tumor sizes <10 cm, 14% were superficial, 23% were non-recurrent and 15% were less than the median cohort patient age of 58 years. If the aforementioned “traditional criteria” were used as the sole basis for MDM2 testing, 50 (46.29%) of the 108 cases that were ultimately classified as MDM2 positive would not have been tested. Conclusion Our findings suggest that a strict adherence to “traditional criteria” may result in a significant subset of MDM2 positive tumors not being tested in lipomatous tumors. A more expansive approach that incorporates additional indications for testing, should be evaluated.

Variability in treatment approaches, outcomes, and recurrence patterns after curative intent treatment for primary retroperitoneal sarcomas in Latin America: A report on 333 patients from LATAMSARC collaborative working group

Background and objectiveRetroperitoneal sarcomas (RPS) are rare tumors with several well-defined histologic subtypes. This study aimed to assess the epidemiology, treatment patterns, and outcomes of patients with retroperitoneal sarcoma in Latin America and analyze patterns of recurrence and treatment variations in a large population of patients treated at reference centers. MethodsThis retrospective descriptive study utilized an electronic database of medical records from LATAMSARC (a group studying sarcomas consisting of different centers in various countries in Latin America, including Argentina, Chile, Costa Rica, Mexico, and Peru). Adult patients (≥18 years) with retroperitoneal sarcoma who underwent surgery at six cancer centers in Latin America were included. Key outcomes were practice patterns, overall survival (OS), and progression-free survival (PFS). ResultsIn this retrospective study, 333 patients diagnosed with retroperitoneal sarcomas met the inclusion/exclusion criteria. The cohort consisted of 157 females (42.3 %) and 176 males (57.7 %), with an average age of 53.9 years (SD 13.37). Histology most commonly included Dedifferentiated Liposarcoma (31.5 %), Well-Differentiated Liposarcoma (29.7 %), and Leiomyosarcoma (9.9 %). The tumors predominantly resided in the retroperitoneum (81.7 %) and showed a mean diameter of 23.53 cm (SD 13.8 cm). Surgical interventions varied, with Complete Compartmental Resection performed in 31.2 % of cases and Simple Complete Resection in 29.4 %. Postoperative complications were documented, with Clavien-Dindo Grade ≥3 complications occurring in 16.8 % of patients. An R0/1 resection was obtained in 91.6 % of cases. The ICU admission rate post-surgery was 18.6 %. Adjuvant treatments included radiotherapy in 8.1 %. Local recurrence occurred in 20.7 % of cases, with the majority being ipsilateral. Distal recurrence was observed in 15 patients, predominantly affecting the liver. The mean overall survival was 65.5 months, and disease-free survival was 47.0 months. ConclusionThis study provides information on the epidemiology, treatment patterns, and outcomes of retroperitoneal sarcomas in a group of reference centers in Latin America. These results represent Latin America's largest body of evidence on retroperitoneal sarcomas.

A rare well-differentiated renal retroperitoneal liposarcoma: a case report

Introduction and importance: Retroperitoneal liposarcomas (RPLPSs) are rare tumors that arise from mesenchymal cells in the peritoneum cavity. The sites of PRLPSs vary a lot, but renal PRLPSs are extremely rare (there are only 45 cases of Renal retroperitoneal liposarcomas on PubMed). In this case, the authors present a rare renal retroperitoneal liposarcoma case, describe the major concepts, and raise awareness about this rare tumor. Case presentation: A 44-year-old woman presented to the clinic with hirsutism and irregular menstruation; upon physical examination, a large abdominal mass was accidentally identified; the patient had Doppler ultrasound (Doppler US) and MRI, which both showed a mass arising from the right upper pole of the kidney, fine needle aspiration (FNA) confirmed the diagnosis of retroperitoneal liposarcoma, patient underwent surgical removal and her symptoms disappeared. Clinical discussion: The retroperitoneum is a cavity behind the abdominal wall containing organs like the pancreas and kidneys. Retroperitoneal tumors (RPTs) are rare neoplasms, primarily of mesenchymal origin. Retroperitoneal liposarcomas (RPLPS) are the most common RPT, often asymptomatic until large, and rarely metastasize but frequently recur. Liposarcomas are classified into five subtypes, with well-differentiated liposarcoma being the most common and characterized by high local recurrence. The presence of specific oncologic mutations affects the prognosis and the response to treatment. Conclusion: In rare cases, retroperitoneal liposarcomas can arise from sites near the kidney and compress the adjoining adrenal gland.

Uncommon Presentation Of A Giant Retroperitoneal Liposarcoma: A Peculiar Case Study

Introduction: Soft tissue sarcomas constitute less than 1% of all neoplasms, with approximately one-third of malignant tumors in the retroperitoneum being sarcomas. Among these, liposarcoma emerges as the most prevalent type. Retroperitoneal liposarcomas with intraperitoneal extension and extension into the inguinal canal are relatively uncommon, presenting a challenge for treatment due to their local aggressiveness and clinical nonspecificity. The clinical difficulty in managing these cases is exacerbated by patients often seeking medical attention late in the disease progression. The slow development and the scarcity of symptoms in the early stages contribute to delayed reporting. Consequently, these tumors are recognized for their capacity to reach enormous sizes before being diagnosed and addressed. Case Report: We present a case involving a 52-year-old man who underwent surgical resection for a massive, well-differentiated retroperitoneal liposarcoma. This tumor exhibited intraperitoneal extension and weighed a substantial 6.8 kilograms. Discussion: Retroperitoneal liposarcomas (RPS) frequently manifest as large, locally advanced lesions. The occurrence of RPS with intraperitoneal extension and extension into the inguinal canal is relatively uncommon. The clinical presentation is often delayed, attributed to the expansive nature of the retroperitoneal space. Evaluating these tumors necessitates a comprehensive, multimodal approach. Given that most RPS are characterized as low-grade, distant metastasis is infrequent, and the primary challenge lies in achieving effective local control and preventing recurrence. The preferred treatment involves radical resection of these tumors, incorporating en bloc resection of involved structures. In certain cases, the strategic use of neoadjuvant and adjuvant therapies, tailored to specific tumor histologies, may enhance local control and overall survival. Conclusion: Effectively managing retroperitoneal liposarcomas necessitates a multidisciplinary approach, ideally conducted at high-volume centers that specialize in the treatment of patients facing these intricate malignancies. Existing data indicate that radical resection stands as the primary opportunity for a cure. In select cases, chemotherapy and radiation therapy may offer a survival benefit, underlining the importance of individualized treatment strategies based on the specific characteristics of the tumor and the patient

Liposarcoma del cordón espermático

Introduction: liposarcoma of the spermatic cord (LSC) is a rare condition and accounts for about 3 to 7% of all paratesticular sarcomas. A case is presented in an 80-year-old patient who consulted for a left inguinoscrotal painless swelling, that had been present for several years. Physical examination revealed a soft left hemiscrotal tumor that appeared not to be adherent to the testicle. Ultrasonography showed a solid, heterogeneous hyperschoic paratesticular mass with central calcifications and peripheral hypervascularity. During surgery, a diffuse lipomatous tumor was found in the spermatic cord on the superior pole of the left testicle, separated from it. Anatomopathological examination revealed a well-differentiated liposarcoma of the spermatic cord. Discussion: this neoplasm features a slow-growing palpable paratesticular mass. This site of occurrence is rare and represents 7 to 10% of all scrotal tumors. Imaging differentiation between LSC and benign lesions is sometimes challenging. Surgical treatment should include radical orchiectomy wide local excision, and spermatic cord and inguinal ring surrounding soft tissue resection. Conclusion: spermatic cord liposarcoma is a rare and unusual mesenchymal tumor and should be considered among the differential diagnoses of scrotal tumors.

A metabolic crosstalk between liposarcoma and muscle sustains tumor growth

Dedifferentiated and Well-differentiated liposarcoma are characterized by a systematic amplification of the Murine Double Minute 2 (MDM2) oncogene. We demonstrate that p53-independent metabolic functions of chromatin-bound MDM2 are exacerbated in liposarcoma and mediate an addiction to serine metabolism to sustain tumor growth. However, the origin of exogenous serine remains unclear. Here, we show that elevated serine levels in mice harboring liposarcoma-patient derived xenograft, released by distant muscle is essential for liposarcoma cell survival. Repressing interleukine-6 expression, or treating liposarcoma cells with Food and Drugs Administration (FDA) approved anti-interleukine-6 monoclonal antibody, decreases de novo serine synthesis in muscle, impairs proliferation, and increases cell death in vitro and in vivo. This work reveals a metabolic crosstalk between muscle and liposarcoma tumor and identifies anti-interleukine-6 as a plausible treatment for liposarcoma patients.

Predictive Value of Quantitative Parameters of 18F-FDG PET/CT in Patients with Liposarcoma.

The purpose of this study was to evaluate the predictive features of baseline F-18-fluorodeoxy-D-glucose positron emission tomography (18F-FDG PET)/computed tomography (CT) parameters in patients with dedifferentiated liposarcomas (DDLPSs) and well-differentiated liposarcomas (WDLPSs) receiving systemic treatment. A total of 24 patients with liposarcoma who underwent longitudinal 18F-FDG PET/CT in systemic therapy were included. All volumetric segmentation of each tumor section and semiquantitative imaging parameters were extracted from the axial field of view from both PET and CT images. Maximum, mean, and minimum standardized uptake values (SUVmax, SUVmean, and SUVmin), Hounsfield units (HUs), and their respective changes from baseline and posttreatment were calculated. The voxel values from unenhanced CT images were correlated with PET-derived parameters. The 18F-FDG uptake decreased by more than 56% on average in responders for both SUVmax and SUVmean in DDLPS. There was a decrease in HUmax in DDLPS among responders. Using AUC > 0.8 as a reasonable predictor, we found that the ratios of SUVmaxD/HUmean, SUVmaxD/HUmedian, and SUVmeanD/HUmedian at baseline were significant indicators of the response to treatment in patients with liposarcoma. The changes in SUVmean and not just SUVmax parameters could be considered as accurate tumor response indicators. For the first time, we introduced baseline SUV/HU ratios as a valuable diagnostic tool in predicting liposarcoma treatment outcomes. This ability was not revealed by classic semiquantitative PET or CT parameters at baseline.