Lymphangioleiomyomatosis Medical Slides

Present the MILES trial (McCormack 2011, NEJM): double-blind RCT of sirolimus vs placebo in LAM patients with FEV1 <70%. Sirolimus stabilized FEV1 (mean change +1 mL/month vs -12 mL/month decline with placebo), improved quality of life, reduced serum VEGF-D levels, and stabilized gas trapping. However, FEV1 decline resumed after drug discontinuation. This established sirolimus as standard of care for progressive LAM, with indefinite treatment recommended.

Present the ATS/JRS 2017 diagnostic criteria: Definite LAM requires characteristic cystic HRCT plus any one of: TSC diagnosis, renal angiomyolipoma, elevated VEGF-D ≥800 pg/mL, chylothorax/chylous ascites, LAM cells in biopsy. Probable LAM: characteristic HRCT plus compatible clinical history (pneumothorax in young woman). VEGF-D has 73% sensitivity and 100% specificity at ≥800 pg/mL threshold — often avoids need for surgical biopsy.

Present the systematic HRCT-based differential: LAM (diffuse, round, thin-walled, uniform cysts in a woman of childbearing age), PLCH (irregular/bizarre-shaped cysts, upper-lobe predominant, smoker), Birt-Hogg-Dubé (lower-lobe/medial predominant cysts, skin fibrofolliculomas, renal tumors, FLCN gene mutation), lymphocytic interstitial pneumonia (lower-lobe ground-glass with cysts, associated with Sjögren syndrome), and cystic metastases (variable wall thickness, cancer history). VEGF-D helps distinguish LAM from mimics.