Conditions: Lymphangioleiomyomatosis
Keywords: Lymphangiomyomatosis Postmenopausal
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 17
Healthy volunteers: no

Brief summary:
The hypothesis in this study is that estrogen suppression by an aromatase inhibitor in postmenopausal women with lymphangioleiomyomatosis (LAM) will prevent or delay progression of lung disease and result in a decrease in the rate of decline in FEV1

Detailed description:
Lymphangioleiomyomatosis, or LAM, is an uncommon, progressive, cystic lung disease that predominantly affects young women. Pulmonary parenchymal changes consistent with LAM are found in about one third of women with tuberous sclerosis complex (TSC), an autosomal dominant tumor suppressor syndrome. LAM also occurs in a sporadic form that is not associated with germline mutations in TSC genes. Recent evidence that recurrent LAM after lung transplantation results from seeding of the graft from a remote source and suggests a metastatic mechanism for the disease.

Since LAM occurs almost exclusively in women, and is exacerbated by pregnancy, menses and hormonal therapies suggest that estrogen suppression might be expected to prevent or delay progression of disease.

In postmenopausal women, estrogens are mainly derived from the action of the aromatase enzyme, which converts adrenal androgens (primarily androstenedione and testosterone) to estrone and estradiol. The suppression of estrogen biosynthesis in peripheral tissues can therefore be achieved by specifically inhibiting the aromatase enzyme. Letrozole is a nonsteroidal aromatase inhibitor (inhibitor of estrogen synthesis) that has been shown to be effective in other neoplasms that affect women, such as breast cancer.

Arms:
arm 1: Patients are placed on letrozole, 1 tablet (2.5 mg) daily for one year arm 2: Patients are placed on placebo, 1 tablet daily for one year

Interventions: intervention 1: Letrozole intervention 2: Placebo
Intervention descriptions: intervention 1: 2.5 mg daily for twelve months intervention 2: placebo given daily for twelve months

Protocol document: