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INTRODUCTION: The pleomorphic variant is the least common and consequently, the least known subtype of liposarcomas. It represents <5 % of all liposarcomas and develops during late adulthood. PRESENTATION OF THE CASE: We report the case of a 77-year-old male who presented with pain in the right iliac fossa and right inguinal region. A CT scan revealed a stony lesion at the level of the cecum. A right hemicolectomy was performed, and the pathology report was positive for pleomorphic liposarcoma. Consequently, he was referred for adjuvant radiotherapy. CLINICAL DISCUSSION: Molecular analysis has validated the distinction of liposarcoma subtypes, although histological subtype remains the reliable prognostic parameter in daily practice, recent evidence suggests that genetic profiles may eventually influence risk stratification of individual patients. CONCLUSION: The pleomorphic subtype of liposarcomas is infrequent, and they are very rare in the cecum, so it is currently recommended that patients be evaluated by a multidisciplinary team to make a therapeutic decision as it is a subtype of very aggressive behavior, before initiating any type of oncologic treatment.

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Se presenta a un paciente con liposarcoma mediastinal gigante con dolor torácico, disnea, cuyos estudios por imágenes revelaban la presencia de una gran tumoración de 42 cm en su diámetro mayor que abarcaba todo el mediastino, comprometía ambas cavidades torácicas, rechazaba los pulmones, corazón y grandes vasos. La biopsia con aguja cortante bajo guía ecográfica fue informada como liposarcoma. El paciente tuvo resección completa del tumor mediante la incisión Clamshell. En el post operatorio inmediato, presentó shock circulatorio más disfunción multiorgánica (DOMS): plaquetopenia, insuficiencia renal aguda con necesidad de soporte dialítico, injuria hepática. El soporte y monitoreo especializado en la Unidad de Cuidados Intensivos (UCI) permitió mejoría clínica y buena evolución. Salió de alta en buenas condiciones.

We present a patient with giant mediastinal liposarcoma with chest pain, dyspnea, whose imaging studies revealed the presence of a large tumor measuring 42 cm in its greatest diameter that covered the entire mediastinum, involved both thoracic cavities, rejected the lungs, heart and big glasses. The sharp needle biopsy under ultrasound guidance was reported as liposarcoma. The patient had complete resection of the tumor through the Clamshell incision. In the immediate postoperative period, he presented circulatory shock plus multiple organ dysfunction (DOMS): plateletopenia, acute renal failure with the need for dialytic support, liver injury. Specialized support and monitoring in the Intensive Care Unit (ICU) allowed clinical improvement and good evolution. He was discharged in good condition.

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INTRODUCTION: conventional parosteal osteosarcoma is an uncommon malignant bone tumor, comprising 4% of all osteosarcomas. Although rare, parosteal osteosarcoma is the most common type of osteosarcoma of the bone surface. We present the clinical, histological and imaging characteristics of a rare histologic variant of a parosteal osteosarcoma, review the literature and emphasize the importance of radio-pathological correlation as well as the interpretation of a representative biopsy in order to obtain the correct diagnosis. CASE REPORT: a 36-year old woman began her condition one year prior to admission to the hospital with increased volume in the left knee and pain. Image studies showed a juxtacortical heterogeneous tumor localized on the posterior surface of the distal femoral metaphysis. An incisional biopsy was performed, with the diagnosis of a Parosteal Osteosarcoma and a wide surgical resection was undertaken. According to the findings of the surgical specimen, the diagnosis of a Parosteal Osteosarcoma with low grade chondrosarcoma and liposarcoma components was made. The knowledge of this rare parosteal osteosarcoma variant can lead the orthopedic oncologists to avoid overlooking the adipose component and provide adequate surgical margins. CONCLUSION: we present the clinical, histological and imaging characteristics of a Parosteal Osteosarcoma with low grade liposarcoma and chondrosarcoma components.

INTRODUCCIÓN: el osteosarcoma parosteal convencional es un tumor óseo maligno poco común, que comprende el 4% de todos los osteosarcomas. Aunque es poco común, el osteosarcoma parosteal es el tipo más común de osteosarcoma de la superficie ósea. Presentamos las características clínicas, histológicas y de imagen de una variante histológica rara de un osteosarcoma parosteal, revisamos la literatura y enfatizamos la importancia de la correlación radio-patológica, así como la interpretación de una biopsia representativa para obtener el diagnóstico correcto. REPORTE DE CASO: mujer de 36 años inició su cuadro un año antes de su ingreso al hospital con aumento de volumen en rodilla izquierda y dolor. Los estudios de imagen mostraron una tumoración heterogénea yuxtacortical localizada en la superficie posterior de la metáfisis femoral distal. Se realizó biopsia incisional, con diagnóstico de osteosarcoma parosteal y se realizó resección quirúrgica amplia. De acuerdo con los hallazgos de la pieza quirúrgica se realizó el diagnóstico de osteosarcoma parosteal con componentes de condrosarcoma y liposarcoma de bajo grado. El conocimiento de esta rara variante de osteosarcoma parosteal puede llevar a los ortopedistas oncólogos a considerar otros componentes y proporcionar márgenes quirúrgicos adecuados. CONCLUSIÓN: presentamos las características clínicas, histológicas y de imagen de un osteosarcoma parosteal con componentes de liposarcoma y condrosarcoma de bajo grado.

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El liposarcoma pleomórfico de vulva es extremadamente raro y hay pocos casos reportados en la literatura. Presentamos el primer caso del Instituto Oncológico Nacional en Panamá. Se trata de una mujer de 52 años con una tumoración vulvar de un año de evolución y de crecimiento lento. Se le toma una biopsia y es referida a nuestro Instituto. Se le realiza hemivulvectomia. La patología confirma liposarcoma pleomórfico con márgenes negativos. Tuvo una evolución postoperatoria favorable. El tratamiento de elección es quirúrgico. El tratamiento adyuvante es individualizado. (provisto por Infomedic International)

Pleomorphic liposarcoma of the vulva is extremely rare and there are few cases reported in the literature. We present the first case from the National Oncologic Institute in Panama. It is a 52-year-old woman with a slow-growing vulvar tumor of one year of evolution. A biopsy was taken, and she was referred to our Institute. A hemivulvectomy was performed. Pathology confirms pleomorphic liposarcoma with negative margins. Postoperative evolution was favorable. The treatment of choice is surgical. Adjuvant treatment is individualized. (provided by Infomedic International)

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Primary hepatic liposarcoma is an extremely rare malignant tumour derived from adipocytes and is part of the group of mesenchymal tumours. We present the case of a 43-year-old Hispanic male patient with a pleomorphic hepatic liposarcoma and absence of MDM2 gene amplification. Two years and six months after surgery, the patient is asymptomatic. The present case is the first report of this entity with positive immunohistochemical testing for p16, p53, S100, vimentin and absence of MDM2 gene amplification.

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El liposarcoma es un tumor de origen mesenquimal que se presenta comúnmente en el retroperitoneo; es de crecimiento lento y su capacidad de producir metástasis depende de su tipo histológico. Este trabajo tiene como propósito presentar un caso de liposarcomas paratesticulares simultáneos con diferentes tipos histológicos, en un paciente masculino, de 80 años con antecedentes de salud y nivel socioeconómico bajo que venía presentando desde hacía dos años aumento de volumen en la región inguinal izquierda y testículo ipsilateral, al inicio fue indoloro; luego, a medida que aumentó de tamaño se tornó doloroso, abarcando la región inguinoescrotal derecha en su totalidad. El examen físico, incluido el signo de la transiluminación fue negativo. El estudio analítico mostró solamente velocidad de sedimentación globular en 95 mm/h y la LDH en 650 U/l; la ecografía testicular mostró una masa heterogénea, solida e hiperecoica, de aspecto graso inguinoescrotal y de más de 30 cm, sin llegarse a observar el testículo. Se realizó exéresis tumoral encontrándose tres tumores liposarcomatosos, dos de ellos con características histopatológicas similares y el otro con patrón histológico diferente. Luego del tratamiento quirúrgico el paciente se recuperó satisfactoriamente y no ha presentado recidiva según los controles periódicos realizados. Se consideró la publicación del caso pues los liposarcomas pueden llegar a confundirse a la exploración clínica con la presencia de una hernia inguinal de contenido graso con sintomatología similar a estas; por lo que debe hacerse una exploración clínica exhaustiva para realizar un correcto diagnóstico. El estudio histopatológico confirmó el diagnóstico de la enfermedad que, además, reveló la presencia de tres tumores liposarcomatosos y dos variantes histopatológicas del mismo, de lo cual no se encontraron reportes en la literatura revisada.

Liposarcoma is a mesenchymal origin tumor that commonly occurs in the retroperitoneum; It is slow growing and its ability to produce metastasis depends on its histological type. The purpose of this work is to present a case of simultaneous paratesticular liposarcomas with different histological types, in an 80-years-old male patient with a health history and low socioeconomic level; For two years he had been experiencing an increase in volume in the left inguinal region and ipsilateral testicle, which at first was painless; Then, as it increased in size, it became painful, covering the entire right inguinoscrotal region. Physical examination, including transillumination sign, was negative. The analytical study only showed erythrocyte sedimentation rate at 95 mm/h and LDH at 650 U/l; The testicular ultrasound showed heterogeneous, solid and hyperechoic mass, with a fatty inguinoscrotal appearance and measuring more tan 30 cm, without the testicle being observed. Tumor excision was performed and three liposarcomatous tumors were found, two of them with similar histopathological characteristics and the other with a different histological pattern. After the surgical treatment, the patient recovered satisfactorily and has not had a recurrence according to the periodic controls carried out. The publication of the case was considered because liposarcomas can be confused on clinical examination with the presence of an inguinal hernia with fatty content with symptoms similar to these; Therefore, a thorough clinical examination must be performed to make a correct diagnosis. The histopathological study confirmed the diagnosis of the disease; which, in addition, revealed the presence of three liposarcomatous tumors and two histopathological variants of the same, from which no reports were found in the reviewed literature.

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Los liposarcomas son neoplasias que se originan de las células mesenquimales, y su localización paratesticular es infrecuente. Se dividen en cuatro subtipos histológicos, siendo el mixoide el más raro. Se muestra el informe de un caso de liposarcoma paratesticular mixoide y una revisión de la literatura, con el objetivo de brindar información sobre esta rara enfermedad. El caso es un paciente masculino de 70 años de edad, que acude a consulta por tumefacción escrotal derecha e indolora de 13 meses de evolución, diagnosticado inicialmente como una hernia inguinal unilateral. Se realizó orquiectomía inguinal radical derecha y ligadura de cordón alto. En anatomía patológica se recibe la pieza quirúrgica de 2500 g. Al estudio histológico se evidencia liposarcoma mixoide. La tomografía computarizada de tórax, abdomen y pelvis no mostró metástasis. La presencia de un liposarcoma debe tenerse en cuenta durante el estudio diagnóstico de masas escrotales, para minimizar la tasa de diagnóstico erróneo y manejo inadecuado.

Liposarcoma are neoplasms that originate from mesenchymal cells, and their paratesticular location is infrequent. They are divided into four histological subtypes, the myxoid being the rarest. The report of a case of myxoid paratesticular liposarcoma and a review of the literature are shown, with the aim of providing information on this rare disease. The case is a 70-years-old male patient who assists the clinic due to painless right scrotal swelling of 13 months evolution, who was initially diagnosed with a unilateral inguinal hernia. Right radical inguinal orchiectomy and high cord ligation were performed. The pathological piece of 2500g is received in pathological anatomy. Myxoid liposarcoma is evidenced at histological study. Chest, abdomen and pelvis computed tomography showed no metastasis. The presence of liposarcoma should be taken into account during the diagnostic study of scrotal masses to minimize the rate of misdiagnosis and inadequate management.

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PURPOSE: Soft tissue sarcomas are rare malignant tumors. Liposarcoma constitutes the most frequent histological subtype of retroperitoneal sarcoma. The prognosis of soft tissue sarcomas depends on clinical and histologic characteristics. OBJECTIVE: Evaluate variables that may be related to the overall and local recurrence-free survival in patients with retroperitoneal liposarcoma and discuss the need for visceral resection en-bloc for tumors. METHODS: A retrospective analysis was conducted of the medical records of 60 patients seen between 1997 and 2017 who underwent surgical resection of retroperitoneal liposarcoma. RESULTS: The overall survival rate at 5 years of follow-up was 75.22% (95% confidence interval [CI] 0.58-0.86). The probability of a local recurrence-free survival at 5 years of follow-up was 26.04% (95% CI 0.11-0.44). The multivariate analysis showed that dedifferentiated or pleomorphic tumors and R2/fragmented resection were associated with a shorter time to recurrence. No other characteristics markedly influenced the overall survival (P > 0.05). CONCLUSION: Patients with dedifferentiated or pleomorphic tumors and incomplete resection were associated with higher local recurrence rates than others. This study reinforces the need for complete and en-bloc resection with organs when there is clear involvement or technical surgical difficulty to maintain the tumor integrity.

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INTRODUCTION: Retroperitoneal Liposarcomas (RL) are a rare form of malignant tumors, they encompass just 5 % ot these and mainly present in female adults between 50 and 60 years of age. They can be divided into 4 morphological subtypes: 1) well-differentiated, 2) undifferentiated, 3) myxoid, and 4) pleomorphic. CASE PRESENTATION: 41-year-old male who present to the outpatient consult of oncological surgery after being diagnosed via imaging with a giant retroperitoneal liposarcoma. The patient reported unsuccessful weight loss attempts and subsequently noticed an increase in abdominal size as well as the development of ulcers in the lower limbs. He underwent radical resection, which included a right nephrectomy, as the primary treatment. DISCUSSION: Giant retroperitoneal liposarcomas are defined as those 30 cm in diameter or more or 20 kg or more in weight are considered "giants" and are extremely rare. The only treatment involves resection of the tumoration and those adjacent involved organs, and sometimes, uninvolved ones. Due to the high risk of recurrence, adjuvant therapy may be provided as well as imaging follow up. CONCLUSION: RL are a complicated entity to manage. They tend to present high rates of recurrence due to the difficulty of performing a full resection without positive margins. These patients should be thoroughly studied before surgery and appropriate follow-up should be provided.

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Los liposarcomas son neoplasias malignas raras que se originan en el tejido adiposo, con mayor frecuencia en el retroperitoneo. De todas las variantes histológicas, el diferenciado es el más común y el de mejor pronóstico. El diagnóstico se establece con pruebas imagenológicas con o sin ayuda de biopsia. El tratamiento consiste en la resección completa del tumor, que puede o no acompañarse de terapia adyuvante. Se presenta el caso de un paciente de 41 años con distensión abdominal y pérdida de peso, en el que se confirma un liposarcoma retroperitoneal mediante una TC abdominal, por lo que fue sometido a una resección quirúrgica completa que resultó exitosa. El paciente se recuperó satisfactoriamente y se mantuvo sin recidivas durante el seguimiento. Se concluye que el diagnóstico y terapéutico varían de acuerdo con las características del tumor y su riesgo de recidiva; por lo que hasta la actualidad continúa siendo un desafío multidisciplinario.

SUMMARY Liposarcomas are rare malignant neoplasms that originate in adipose tissue, most frequently in the retroperitoneum. Of all histological variants, differentiated liposarcoma is the most common and has the best prognosis. Diagnosis is established by imaging tests with or without the aid of biopsy. Treatment consists of complete resection of the tumour, which may or may not be accompanied by adjuvant therapy. We present the case of a 41-year-old patient with abdominal distension and weight loss, who was confirmed to have retroperitoneal liposarcoma by abdominal CT scan and underwent successful complete surgical resection. The patient recovered satisfactorily and remained free of recurrence during follow-up. It is concluded that diagnosis and therapy vary according to the characteristics of the tumour and its risk of recurrence, which is why it remains a multidisciplinary challenge to this day.

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Lipomas are mesenchymal neoplasms relatively uncommon in the oral cavity. Lipomas can exhibit histopathological features mimicking atypical lipomatous tumors (ALT) or dysplastic lipoma (DL) in the presence of degenerative changes. Relevantly, immunohistochemistry assists in the correct diagnosis. Herein, we present the case of a 54-year-old male with a sessile nodule located on the dorsum of the tongue. The histopathological analysis showed a diffuse, non-circumscribed adipocytic proliferation constituted by cells of variable size containing cytoplasmic vacuoles and displaced nuclei, some resembling lipoblasts supported by fibrous connective tissue stroma. By immunohistochemistry, tumor cells were positive for vimentin, S100, FASN, CD10, and p16. Rb expression was intact. Moreover, CD34, p53, MDM2, and CDK4 were negative. After 2-year of follow-up, no alteration or recurrence was observed. In conclusion, MDM2, CDK4, p53, and Rb immunomarkers can be used reliably to differentiate benign lipoma with degenerative changes from ALT and DL.

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ABSTRACT Lipomas are mesenchymal neoplasms relatively uncommon in the oral cavity. Lipomas can exhibit histopathological features mimicking atypical lipomatous tumors (ALT) or dysplastic lipoma (DL) in the presence of degenerative changes. Relevantly, immunohistochemistry assists in the correct diagnosis. Herein, we present the case of a 54-year-old male with a sessile nodule located on the dorsum of the tongue. The histopathological analysis showed a diffuse, non-circumscribed adipocytic proliferation constituted by cells of variable size containing cytoplasmic vacuoles and displaced nuclei, some resembling lipoblasts supported by fibrous connective tissue stroma. By immunohistochemistry, tumor cells were positive for vimentin, S100, FASN, CD10, and p16. Rb expression was intact. Moreover, CD34, p53, MDM2, and CDK4 were negative. After 2-year of follow-up, no alteration or recurrence was observed. In conclusion, MDM2, CDK4, p53, and Rb immunomarkers can be used reliably to differentiate benign lipoma with degenerative changes from ALT and DL.

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O Sarcoma de partes moles é um tumor maligno raro, correspondendo a aproximadamente 1% dos tumores malignos em adultos. Objetivamos descrever um raro caso de Lipossarcoma pleomórfico em paciente jovem, sem história familiar, que representa 0,3% dos sarcomas da mama. Relatamos o caso de uma paciente do sexo feminino, 39 anos, com nodulação em prolongamento axilar de mama esquerda, cujas mamografia e ecografia caracterizaram nodulação regular, de limites definidos, sem fluxo central ou periférico e ecotextura heterogênea. A Core-Biopsy diagnosticou neoplasia maligna fusocelular. Realizada ressecção segmentar, cujos laudos histopatológico e de imuno-histoquímica concluíram como sendo Lipossarcoma pleomórfico de alto grau. O sarcoma pleomórfico é um subtipo raro e agressivo entre os lipossarcomas. O seu tratamento, assim como dos sarcomas de mama, é a ressecção cirúrgica com margens de segurança; a terapia adjuvante com radioterapia é indicada devido à taxa de recorrência deste tumor. A quimioterapia ainda tem papel indefinido nesses tipos de tumores. Concluímos que, por ser o Lipossarcoma pleomórfico uma neoplasia maligna rara, o diagnóstico e a conduta adequados se fazem necessários para prover terapêutica precisa e conter metastatização e recidiva local.

Soft tissue sarcoma is a rare malignant tumor, accounting for approximately 1% of malignant tumors in adults. We aim to describe a rare case of pleomorphic liposarcoma in a young patient with no family history, representing 0.3% of breast of breast sarcomas. We report the case of a 39-year-old female patient with nodulation in the axillary extension of the left breast, whose mammogram and ultrasonography characterized a regular nodulation, with defined limits, without central or peripheral flow, and heterogeneous echotexture. The Core-Biopsy diagnosed malignant fusocellular neoplasm. Segmental resection was performed. The histopathological and immunohistochemistry reports concluded that it was a high grade pleomorphic liposarcoma. Pleomorphic sarcoma is a rare and aggressive subtype among the liposarcomas. Its treatment, as with breast sarcomas, is surgical resection with safety margins; adjuvant therapy with radiotherapy is indicated due to the recurrence rate of this tumor. Chemotherapy still has an undefined role in these types of tumors. We conclude that, because pleomorphic liposarcoma is a rare malignant neoplasm, the diagnosis and management are necessary to provide an accurate therapy and contain metastasis and local recurrence.

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Werner's syndrome is caused by the inactivation of both WRN alleles and is characterized by premature aging and increased risk of neoplasms, especially those of mesenchymal origins, such as sarcomas. Given the characteristic genomic instability, patients with this syndrome are more susceptible to develop toxicities when exposed to cytotoxic agents, such as alkylators and anthracyclines. The impact of the monoallelic WRN mutation on treatment-associated toxicities is poorly understood. Here, we report a patient with locally advanced dedifferentiated liposarcoma of the retroperitoneum harboring a heterozygous germline inactivation mutation in the WRN gene, who was treated with a classic regimen of ifosfamide and doxorubicin and developed exacerbated and prolonged hematological and renal toxicities.

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Retroperitoneal liposarcomas are very infrequent retroperitoneal malignant tumours. Most patients complain of palpable abdominal mass and only half present with abdominal pain. With haematogenous spread they can reach, mainly, lungs and liver, but only in 10% of cases. Here we report the presentation and surgical treatment of a giant massive retroperitoneal liposarcoma in a 53-year-old man.

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Retroperitoneal liposarcomas are very infrequent retroperitoneal malignant tumours. Most patients complain of palpable abdominal mass and only half present with abdominal pain. With haematogenous spread they can reach, mainly, lungs and liver, but only in 10% of cases. Here we report the presentation and surgical treatment of a giant massive retroperitoneal liposarcoma in a 53-year-old man.

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Resumen ANTECEDENTES: Los liposarcomas son un tipo de tumor de partes blandas. El subtipo desdiferenciado es una de las variantes más comunes junto con el liposarcoma bien diferenciado. CASO CLÍNICO: Paciente de 68 años que acudió a consulta por aparición de una masa en la zona vaginal que clínicamente se diagnosticó como hernia inguinal directa. Se procedió a la resección quirúrgica de la masa. El reporte histopatológico fue de miofibrolipoma, sin atipias y con bordes libres de neoplasia. Tres años después, la paciente retornó a la consulta por reaparición de la masa y se negó a una nueva biopsia. Posteriormente, en el 2020, la paciente aceptó la resección de la masa; el reporte histopatológico fue: liposarcoma desdiferenciado con diferenciación lipoblástica homóloga a liposarcoma pleomórfico. CONCLUSIÓN: Los estudios histopatológicos son necesarios para la confirmación del diagnóstico y la resección quirúrgica es el tratamiento de elección.

Abstract BACKGROUND: Liposarcomas are a type of soft tissue tumor. The dedifferentiated subtype is one of the most common variants along with well-differentiated liposarcoma. CLINICAL CASE: A 68-year-old female patient presented for consultation due to the appearance of a mass in the vaginal area which was clinically diagnosed as a direct inguinal hernia. Surgical resection of the mass was performed. The histopathological report was myofibrolipoma, without atypia and with borders free of neoplasia. Three years later, the patient returned to the office for recurrence of the mass and refused a new biopsy. Subsequently, in 2020, the patient accepted the resection of the mass; the histopathologic report was: dedifferentiated liposarcoma with lipoblastic differentiation homologous to pleomorphic liposarcoma. CONCLUSION: Histopathological studies are necessary for confirmation of the diagnosis and surgical resection is the treatment of choice.

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We report a rare case of dedifferentiated liposarcoma in a man. A 60-year-old male patient presented with a left mass involving the whole breast area, with no lymph node enlargement, growing during a one-year-period. Imaging studies revealed a fat-containing mixed-density mass apparently associated with the pectoralis major muscle. A core biopsy was performed that yielded a diagnosis of a well-differentiated liposarcoma. Further tests to check for metastases were ordered and no distant disease was found. Left mastectomy with en bloc resection of the pectoralis major muscle was performed. The pathologic diagnosis revealed a high-grade dedifferentiated liposarcoma with extensive necrosis. This tumor type is primarily described in the retroperitoneum and extremities. We report an unusual presentation of a liposarcoma mimicking a breast mass.

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Liposarcomas are malignant mesenchymal tumours usually located in the retroperitoneum, rarely occurring as a single lesion in the kidney. We present a case of a 59-year-old male patient with a left renal mass detected by computed tomography scan. He underwent radical nephrectomy and the histopathological study reported a primary undifferentiated liposarcoma of the kidney without nodal involvement. After 15 months of surgery, he remained asymptomatic and without evidence of disease recurrence. The objective of this report is to present a case and literature review with current evidence of treatment options and prognostic factors for survival.

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Sarcomas are a heterogenous group of malignant tumors with origin or mesenchymal differentiation, they comprise 1-2% of all solid tumors. Retroperitoneum is the second most frequent site affected. Prognosis is worse compared to the limbs, with a 5y OS of 36-58%, and 50-60% patients will relapse. Dedifferentiated liposarcomas (ddLPS) are more aggressive, it is known that presence of a de-differentiated component increases the probability of distant recurrence and lowers OS. There is little information about the specific impact of each type of de-differentiation. To determine if the presence of myogenic differentiation markers in DDLPS is an adverse prognostic factor. A retrospective, observational, analytic cohort study was performed. Cases identified from the electronic clinical files from the National Cancer Institute in Mexico City, we included cases from January 1st 2005 to December 31st 2016. We correlated the presence of expression of myogenic markers (Smooth muscle actin, Calponin, H-caldesmon, Desmin and Myogenin) in the dedifferentiated component of DDLPS with overall survival and surgical outcomes. One hundred and forty-three cases were analyzed. Eighty-two were liposarcomas, and 38 had a dedifferentiated component. Of these 38 cases, 21(55.3%) were males and, 17(44.7%) were females. Median age was 54.1(27-79) years, median tumor size was 28 cm (13-56). Most patients had locally advanced disease: 32(84.2%) were in stage IIIB. 2.6% had metastatic disease and 5(13.2%) had stage Ib at diagnosis. Myogenic marker expression was found in 18.4% of cases; these patients had a worse median survival than cases with no myogenic expression: 18 months (95% CI 15.4-20.5) vs 32 months (95% CI 21.8-42.1) p = 0.01, we also found a relation with higher postoperative morbidity in these cases (p = 0.045). The presence of myogenic differentiation markers might be associated with a worse prognosis, in our series it corelated with worse OS, however it is not a common event. Relation with surgical morbidity is to be analyzed in further studies.