Liposarcoma vulvar desdiferenciado con diferenciación homóloga a liposarcoma pleomórfico: reporte de caso / Dedifferentiated vulvar liposarcoma with homologous differentiation to pleomorphic liposarcoma: case report

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.

Long-Term Survival of a Patient with Recurrent Dedifferentiated High-Grade Liposarcoma of the Retroperitoneum Under Adjuvant Treatment with Viscum album L. Extract: A Case Report.

CASE PRESENTATION: A 68-year-old male patient underwent a resection of a DDL (T2 N0 M0, FNCLCC grade 2, stage IIIA) in the retroperitoneum. Three months after this first surgery, a recurrence occurred, and was treated with neoadjuvant and adjuvant doxorubicin plus ifosfamide and surgery (resection). A second recurrence-11 months after the second surgery-was treated with surgery and radiotherapy. The patient then began to undergo VAE treatment (0.2 mg-2 mg, subcutaneously, thrice a week). After the VAE treatment was initiated, the patient reported improved quality of life. A third recurrence-12 months after the third surgery-was treated with surgery, radiotherapy, and with an increased dose of VAE (20 mg). Sixty-nine months (5.8 years) after the fourth surgery a fourth recurrence occurred. It was again treated with surgery, along with a month of intravenous VAE infusions and subsequent subcutaneous VAE (20 mg) treatment. Finally, a fifth recurrence-5 months after the fifth surgery-was treated with subcutaneous and intravenous VAE applications and eribulin. The patient died 11 months after the last recurrence; he received a total of 103 months (8.6 years) of VAE treatment and achieved 10.5 years of survival. CONCLUSION: The case presented herein shows a long-time survival and a prolonged recurrence-free interval in a patient with retroperitoneal DDL treated with surgery, chemotherapy, radiotherapy, and VAE injections. On the basis of the antitumoral and immunomodulating effects of VAE and on the reported prolonged survival of VAE-treated patients with other types of tumors, the adjunct VAE treatment is presumed to have contributed to the favorable outcome. Regarding the clinical relevance of VAE treatment, further investigations are needed.

Anti-tumor activity of the MDM2-TP53 inhibitor BI-907828 in dedifferentiated liposarcoma patient-derived xenograft models harboring MDM2 amplification.

PURPOSE: Dedifferentiated liposarcoma (DDLPS) is a soft tissue malignancy characterized by amplification of the mouse double minute 2 homolog (MDM2) gene. MDM2 is a negative regulator of tumor protein 53 (TP53). We tested the in vivo efficacy of BI-907828, a small molecule inhibitor of the MDM2-TP53 interaction, in two DDLPS patient-derived xenografts (PDX). METHODS: Partially immunodeficient mice were bilaterally engrafted with UZLX-STS3 (n = 24) and UZLX-STS5 (n = 24) human DDLPS tissue harboring MDM2 amplifications. Mice were grouped as follows: (a) vehicle (0.5% hydroxyethylcellullose) 10 ml/kg daily per os (p.o.); (b) doxorubicin 5 mg/kg weekly intraperitoneally (i.p.); (c) BI-907828 2.5 mg/kg daily p.o. and (d) BI-907828 10 mg/kg daily p.o. The treatment lasted for 15 days, all mice treated with BI-907828 were followed for 37 days post-treatment. Efficacy was assessed by tumor volume and histopathological evaluation. RESULTS: The 15-day treatment with 2.5 mg/kg and 10 mg/kg BI-907828 significantly inhibited tumor growth in UZLX-STS5 and -STS3 (p < 0.0001 compared to control for both models). All UZLX-STS5 and -STS3 tumors treated with BI-907828 decreased in size during treatment, and BI-907828-treated UZLX-STS5 tumors even disappeared completely. During the follow-up period, no tumor regrowth was observed in the UZLX-STS5 model and both doses of BI-907828 led to a pathological complete response, whereas a dose-dependent regrowth was seen in the UZLX-STS3 model. CONCLUSION: BI-907828 showed significant anti-tumor activity in DDLPS PDX harboring MDM2 amplifications, providing a strong rationale for early clinical testing of BI-907828 in a DDLPS patient population.

Dedifferentiated liposarcoma of the gallbladder: first reported case.

BACKGROUND: Liposarcoma of the gallbladder is an extremely rare sarcoma, with only five cases reported in the literature according to our knowledge. CASE PRESENTATION: A 71-year-old woman was referred to the Surgical Oncology Division of Napoleão Laureano Hospital (João Pessoa, PB, Brazil) due to a solid mass at the right side of the abdomen and fever, with no signs of jaundice. Abdominal ultrasonography and computed tomography (CT) evidenced an extensive gallbladder lobular formation adhered to the inferior border of the right hepatic lobe and cholelithiasis. The CT report suggested gallbladder liposarcoma. A cholecystectomy associated with resection of segments IV-B and V of the liver were performed. Intraoperative frozen sections were compatible with gallbladder sarcoma. Anatomopathological examination and immunohistochemistry confirmed dedifferentiated liposarcoma with foci of heterologous leiomyosarcomatous differentiation and undifferentiated fusocellular areas of high histological grade. CONCLUSION: This is the first case of dedifferentiated liposarcoma of the gallbladder to be reported.