Breast liposarcoma with solitary metastasis to the pleura: A case report.

Rationale: Breast cancer is the most prevalent malignancy in women worldwide. Our patient presented with a history of breast liposarcoma (LPS) and was found to have pleural metastasis during the initial workup.

Patient Concerns: The patient was complaining about chest pain and dyspnea that had persisted for a week.

Diagnoses: After a full evaluation and histological diagnosis, she was diagnosed as metastatic breast LPS.

Interventions: We adopted 6 cycles of pegylated liposomal doxorubicin (PLD) plus ifosfamide as 1st-line palliative chemotherapy, combined with local pleural effusion management.

Outcomes: The patient's symptoms were notably relieved, and both malignant metastatic lesions and pleural effusion were controlled.

Lessons: Although metastatic breast LPS is rarely reported and incurable, more clinical experience and use of next-generation sequencing should be helpful in finding the effective treatment for metastatic LPS.