The topic Atypical Lipomatous Tumor  you are seeking is a synonym, or alternative name, or is closely related to the medical condition Well-Differentiated Liposarcoma.

Quick Summary:

• Well-Differentiated Liposarcomas (WDLSs) are usually slow-growing, malignant soft tissue tumors. They are well-circumscribed and typically present on the retroperitoneum, limbs, and mediastinum (chest region)
• The cause of development of these tumors is unknown, but some genetic mutations have been observed
• The treatment course includes complete surgical excision, which is usually curative. Since, Well-Differentiated Liposarcomas do not metastasize, the prognosis is typically excellent with early detection and removal of the tumor
• The World Health Organization (WHO) classifies Well-Differentiated Liposarcomas into 4 types:
  • Lipoma-like Well-Differentiated Liposarcoma: These tumors have very good prognosis upon complete removal. However, since the tumors resemble benign lipomas, their diagnosis may be difficult
  • Sclerosing Well-Differentiated Liposarcoma: It is frequently found in the retroperitoneum followed by paratesticular region. in this tumor, there is the presence of fibrosis, when the tumor is examined by a pathologist under the microscope
  • Inflammatory Well-Differentiated Liposarcoma: Prominent inflammatory cells are found in the tumor, when it is examined by a pathologist under the microscope
  • Spindle Cell Well-Differentiated Liposarcoma: In addition to the retroperitoneum and spermatic cord, these tumors are also found to occur in the subcutaneous tissue. On a pathological examination of this soft tissue tumor under a microscope, there may be spindle cell areas, which give the tumor its name
• A liposarcoma (LPS or LS) is a rare and malignant tumor of the fat cells. They are generally asymptomatic and can occur anywhere in the body
• There are 4 main types of liposarcomas and these include:
  • Well-Differentiated Liposarcoma (WDLS): Approximately 45% of all types of liposarcomas are well-differentiated
  • Dedifferentiated Liposarcoma: It is a high-grade morphology tumor
  • Myxoid Liposarcoma: This type constitute 30% of all liposarcomas        
  • Pleomorphic Liposarcoma (PLS): It is the rarest type and constitute about 5% of all liposarcomas

Please find comprehensive information on Well-Differentiated Liposarcoma regarding definition, distribution, risk factors, causes, signs & symptoms, diagnosis, complications, treatment, prevention, prognosis, and additional useful information HERE.