Low-dose sirolimus in retroperitoneal lymphangioleiomyomas

Area of Science:

• Rare diseases
• Oncology
• Pulmonology

Background:

• Lymphangioleiomyomatosis (LAM) is a rare multisystem disorder characterized by cystic lung destruction and abdominal tumors.
• Retroperitoneal lymphangioleiomyomas are common abdominal manifestations of LAM.
• Current sirolimus therapy for LAM focuses on lung function, targeting serum trough levels of 5-15 ng/mL.

Observation:

• A patient with sporadic LAM presented with retroperitoneal lymphangioleiomyomas.
• The patient was treated with low-dose sirolimus, achieving serum trough levels below 5 ng/mL.

Findings:

• Treatment with low-dose sirolimus resulted in a significant reduction of retroperitoneal lymphangioleiomyomas.
• This outcome was observed despite serum trough levels being below the currently recommended range for lung function.

Implications:

• Low-dose sirolimus may be an effective therapeutic option for managing retroperitoneal lymphangioleiomyomas in LAM patients.
• Further research is warranted to explore the efficacy and safety of lower sirolimus doses for LAM-associated tumors.
• This approach could offer an alternative for LAM patients who may not tolerate or require higher sirolimus doses for lung disease.