SUN-446 RENAL ANGIOMYOLYPOMAS IN SPORADIC LYMPHANGIOLEIOMYOMATOSIS

Abstract

Lymphangioleiomyomatosis (LAM) is a rare multisystem disease that mostly afflicts young women. The average age at presentation is typically between the mid-thirties and mid-forties but can extend to eighties. Sporadic LAM is used for patients with LAM not associated with tuberous sclerosis complex (TSC). A 46 year old female initial presentation with shortness of breath at age of 43. Part of her evaluation for dyspnea included CT Chest which showed multiple thin-walled cysts and some reticular changes, which were compatible with Lymphangioleiomyomatosis and chronic interstitial lung disease, pulmonary function test revealed an obstructive pattern. CT and MRI abdomen done for surveillance showed multiple hepatic hemangiomas with bilateral renal masses represents angiomyolipoma. She had no other pulmonary complications. Patient denied personal of family history of seizure disorders, no skin lesions apart from the chronic idiopathic urticaria. There is no family history of Tuberos sclerosis. Her renal function was normal through out her follow up period. started initially on tamoxifen but she was shifted to sirolimus due to side effects. Follow up imaging showed stable renal masses. Clinical presentation: Pulmonary manifestations include fatigue, progressive dyspnea, spontaneous pneumothorax, pleural effusion which is most likely due to chylothorax and occurs in 10-30 % of patients in LAM. Exertional dyspnea is the most common presenting symptom and 1/3 of women with LAM have reversible airflow obstruction, which is confused with other obstructive lung diseases. Non pulmonary manifestations include Renal angiomyolipomas (AMLs) which are benign masses that contain blood vessels, muscle tissue, and fat. They occur in approximately 30% of patients with sporadic LAM & usually asymptomatic unless lesions are >4 cm it may present with abdominal pain due to hemorrhage specially if the mass contains aneurysm. Tuberous sclerosis is suspected if lesions are large, bilateral and multiple or if there is renal impairment. usually it is incidentally discovered on CT abdomen but Ct chest should be considered in case of large, bilateral lesions are present,11 % of patients with sporadic AMLs have cystic changes in the lung consistent with LAM. Renal AMLs are typically diagnosed by the presence of fat within a renal tumor on non contrast-enhanced CT. Fat-free or fat-poor AMLs can also occur, and must be distinguished from renal cell carcinomas, oncocytomas, or other more aggressive neoplasms, which can rarely complicate TSC and sporadic LAM.MRI can be more sensitive for detecting fat density. Vascular endothelial growth factor-D, VEGF-D levels are measured in the serum of patients with suspected LAM, in whom typical thin-walled cysts are found on chest CT and it is diagnostic for LAM if the level is greater than or equal to 800 pg/mL. The primary histopathologic abnormality is the proliferation of atypical smooth muscle like cells (LAM cells). Sirolimus, mTOR inhibitor, is a supportive but not curative medication. Lung function goes back to pretreatment function upon discontinuation of the medication,. Most renal angiomyolipomas do not require specific treatment unless big or hemorrhagic. Big tumors can be treated with embolization, radiofrequency ablation or partial nephrectomy if not responding to mTOR therapy.