A retrospective study of patients with malignant PEComa receiving treatment with sirolimus or temsirolimus: the Royal Marsden Hospital experience.

UNLABELLED: Perivascular epithelioid cell tumors (PEComas) are rare tumors driven by tuberous sclerosis complex gene mutations causing up-regulation of mTOR. We report the outcome of ten consecutive patients treated with sirolimus or temsirolimus.

PATIENTS AND

METHODS

A retrospective analysis was performed on patients seen between 2007 and 2013. Demographic and treatment data were collected and radiological response was assessed.

RESULTS

Ten patients were investigated, eight females, with median age of 47.5 years. Nine patients received sirolimus, one temsirolimus. The median treatment duration was 128 (range=7-1,366 days). Temsirolimus was given at 25 mg IV weekly and median starting dose of sirolimus was 3 mg daily. Seven patients were evaluable for response by RECIST: 5 showed partial response (50%), 1 stable disease (10%) and 1 progressive disease (10%). Two patients progressed rapidly on treatment. One patient stopped due to grade 3 hyperlipidaemia although CT scan shows maintained response. Three patients continue on treatment while the remainder stopped due to disease progression.

CONCLUSION

Our study confirms that mTOR inhibition with sirolimus/temsirolimus is well-tolerated with good radiological responses, albeit short-lived, and supports its use in PEComas.