MON-914 Ectopic ACTH Syndrome Caused by Adenocarcinoma of Lung - a Rare Association with Rare Complication

INTRODUCTION Ectopic ACTH constitutes 5-10% of ACTH dependent Cushing’s syndrome. Evolution of symptoms can be rapid. Cortisol & ACTH is usually higher as compared to Cushing’s disease. Imaging studies should be obtained for localization of the source of ACTH. Here, we present a case of Cushing’s syndrome caused by ectopic ACTH production caused by adenocarcinoma lung, which has very rarely been associated with this syndrome CASE A 52-year-old male presented with 3-month H/O bilateral pedal edema & puffiness of face. He noticed bruises over his trunk & darkening of face for 2 months. There was a recent worsening of his HTN (requiring 3 antihypertensives) & recently diagnosed with DM. On examination patient had cushingoid features, acne and ecchymosis. BP - 166/110 mm Hg. Proximal myopathy, Pedal edema, clubbing & cervical lymphadenopathy was present (largest node - 2.5cm). Fasting & postprandial blood sugars were 190 & 285 mg/dl respectively. Serum K(+) was 3.0 meq/L (3-5-5.0meq/L), 11pm serum cortisol was 51.6 mcg/dl (cutoff < 7,5mcg/dl), 8 am cortisol after overnight 1mg dexamethasone was 60.7 mcg/dl (cutoff<1.8mcg/dl). Serum ACTH(8am) - 178 pg/ml.(>20 pg/ml-ACTH dependent Cushing’s) Biopsy of neck node revealed poorly differentiated adenocarcinoma. PET scan showed left lung upper & lower lobe masses. A diagnosis of ectopic ACTH syndrome was made, the source of which was adenocarcinoma of lung, which has been very rarely reported to be associated with it. Oral ketoconazole was started followed by Chemotherapy with paclitaxel & carboplatin. Within the next 7 days patient developed pleural effusion, neutropenia & worsened rapidly. BAL revealed Nocardia species, known to be associated with hypercortisolism. He was treated with appropriate antibiotics & supportive treatment but succumbed to septic shock. CONCLUSION If a patient presents with rapidly evolving symptoms of Cushing’s syndrome, ectopic ACTH syndrome should be considered. The presence of wasting and weight loss, hypokalemic alkalosis, pedal edema & marked hyperpigmentation should also alert towards the diagnosis. Histopathological confirmation of malignancy is important, as in our case with ectopic ACTH where the source was an adenocarcinoma of the lung, of which only 5 cases have been reported till now (Ectopic ACTH more commonly associated with SCLC). Finally, in cases of severe hypercortisolemia, there should be a high index of suspicion for opportunistic infections including invasive fungal infections, Nocardiosis etc, so that specific antibiotic therapy can be initiated. Typical features like fever, leukocytosis can be absent. Treatment of underlying hypercortisolism with surgical/medical management prior to initiation of chemotherapy has been shown to reduce the frequency of infections.