SESSION TITLE: Medical Student/Resident Diffuse Lung Disease SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Lymphangioleiomyomatosis (LAM) is a rare systemic disease resulting in cystic lung destruction, recurrent pneumothoraces, chylous pleural effusions, and abdominal tumors. This multisystem disease most commonly affects women of childbearing age, resulting in stepwise decline in pulmonary function, with clinically apparent hypoxemia developing in most patients within a decade after onset of symptoms. Here we present a rare case of late-onset LAM with concurrent high grade B-cell lymphoma. CASE PRESENTATION: The patient is a 62-year-old female nonsmoker with a remote history of spontaneous pneumothorax who presented due to pleuritic chest pain at rest. Chest CT revealed innumerable pulmonary cysts up to 15 mm, few solid noncalcified pulmonary nodules, multiple complex mediastinal lesions, and a 30% left anterior pneumothorax. Chest tube was placed; the patient was admitted. A nontender swelling was noted on the skull which the patient attributed to a work injury several months prior. MRI showed a 5 cm lytic lesion involving the left frontal bone and subgaleal space with hypercellular diffusion pattern. Craniectomy with resection was performed; pathology revealed high-grade B cell lymphoma. CT abdomen revealed a 4x4 cm right-sided irregular exophytic renal mass. The patient had VEGF-D level of 1382 pg/mL, which, combined with diffuse cystic lung disease, was consistent with a diagnosis of LAM. The patient was discharged and underwent chemotherapy and radiation in the outpatient setting. Two months later, she was readmitted with recurrent left pneumothorax. She failed doxycycline chemical pleurodesis (as there was a nation-wide talc shortage) and went for VATS decortication, pleurectomy, LLL wedge resection, and mechanical pleurodesis. Immunohistochemistry studies on lung pathology confirmed LAM (Table 1). DISCUSSION: LAM may develop sporadically, or may arise in a patient with preexisting tuberous sclerosis complex. The clinical presentation varies and may include cough, dyspnea, recurrent pneumothorax, pleural effusion, or respiratory failure. Overall, the patient’s family history and clinical presentation was not consistent with tuberous sclerosis complex. This is a case of likely sporadic LAM in a patient with recurrent pneumothorax, the first being 5 years prior to this presentation. The concurrent diffuse large B cell lymphoma of the skull adds an interesting twist, as there have only been case reports of LAM occurring with malignant lymphoma. CONCLUSIONS: Although LAM is diagnosed at a median age of 35, more women are being diagnosed at an older age. Pleurodesis after the first occurrence of pneumothorax should be considered due to the high rate of recurrence, as seen in this patient who had multiple pneumothoraces and failed chemical pleurodesis. Sirolimus is also recommended for LAM but this patient’s concurrent treatment for lymphoma complicates her treatment options. Reference #1: McCormack FX, Gupta N, Finlay GR, et al. Official American Thoracic Society/Japanese Respiratory Society Clinical Practice Guidelines: Lymphangioleiomyomatosis Diagnosis and Management. Am J Respir Crit Care Med. 2016;194(6):748-761. doi:10.1164/rccm.201607-1384ST Reference #2: Park S, Lee EJ. Diagnosis and treatment of cystic lung disease. Korean J Intern Med. 2017 Mar;32(2):229-238. doi: 10.3904/kjim.2016.242. Epub 2017 Feb 28. Reference #3: Jawad H, Walker CM, Wu CC, Chung JH. Cystic interstitial lung diseases: recognizing the common and uncommon entities. Curr Probl Diagn Radiol. 2014 May-Jun;43(3):115-27. doi: 10.1067/j.cpradiol.2014.01.001. DISCLOSURES: No relevant relationships by Helen Li Mitchell, source=Web Response No relevant relationships by Sushant Soni, source=Web Response No relevant relationships by Justin Thomas, source=Web Response No relevant relationships by Shawnt Tosonian, source=Web Response