PARESTHESIA, PAIN, AND ANOSMIA: AN UNCOMMON PRESENTATION OF LUNG CANCER

Abstract

SESSION TITLE: Case Report Semifinalists 11 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/21/2019 02:30 PM - 03:15 PM INTRODUCTION: While paraneoplastic neurological disorders (PND) remain underreported in small cell lung cancer (SCLC), they have been most commonly associated with this tumor as compared with other forms of lung malignancy CASE PRESENTATION: An 84 year-old female with history of prior tobacco abuse presented following a fall, causing right hip fracture. She reported a 1 year history of debilitating symptoms of numbness and pain beginning in her feet, which gradually progressed to involve her distal lower extremities, and similar symptoms subsequently developing in her hands and progressing to involve both upper extremities and left shoulder accompanied by weakness in both upper and lower extremities, with subsequent loss of balance contributing to her fall. Additionally she reported total loss of smell, altered taste, early satiety, and an unintentional weight loss of 30 lbs. She had been evaluated in the outpatient setting and underwent an unremarkable upper endoscopy, colonoscopy, chest X-ray, and CT-scan of the abdomen/pelvis. An EMG demonstrated diffuse sensory polyneuropathy involving both upper and lower extremities. Prior to her presentation to the ED, serologic testing for a suspected paraneoplastic process was performed. On presentation, neurologic examination was notable for fluent speech, normal orientation and cognition, anosmia, normal cranial nerve II-XII testing, and diffuse bilateral upper and lower extremity weakness. Laboratory evaluation demonstrated normocytic anemia (HCT 31), otherwise unremarkable. During hospitalization, the paraneoplastic workup ordered by her neurologist returned as positive for ANNA-1 and CRMP-5-IgG titers. A CXR was repeated and demonstrated a well-circumscribed density in the superior left hilar region, new compared to prior imaging. CT chest demonstrated a 3.2 x 4.8 x 4.8 cm mass in the left hilar region, adjacent to the left mainstem bronchus with narrowing the left pulmonary artery, and a filling density within the left inferior pulmonary vein extending to the left atrium concerning for thrombosis or direct tumor extension. A PET/CT demonstrated a hypermetabolic left hilar mass and hypermetabolic pretracheal and bilateral hilar adenopathy. Biopsy demonstrated small cell lung cancer. DISCUSSION: We add to the literature a case of a diffuse sensory, motor and cranial neuropathy attributable to paraneoplastic neurologic syndrome secondary to SCLC. Lambert Eaton myasthenic syndrome and limbic encephalitis are the most commonly described PND associated with SCLC. Although peripheral sensory neuropathy is well described with SCLC, especially in the presence of positive onconeural antibodies (mainly ANNA-1 and CRMP-5), such extensive neurological involvement has rarely been described. CONCLUSIONS: This case highlights the need to consider early evaluation for underlying malignancy in patients with otherwise unexplained diffuse neurologic symptoms Reference #1: Gozzard, P., Woodhall, M., Chapman, C., Nibber, A., Waters, P., Vincent, A., Lang, B., Maddison, P. (2015). Paraneoplastic neurologic disorders in small cell lung carcinoma: A prospective study. Neurology, 85(3), 235-9 Reference #2: Raspotnig M., Vedeler C., Storstein A. (2015) Paraneoplastic neurological syndromes in lung cancer patients with or without onconeural antibodies. Journal of the Neurological Sciences, 348 (1-2) , pp. 41-45. Reference #3: Kanaji, N., Watanabe, N., Kita, N., Bandoh, S., Tadokoro, A., Ishii, T., Dobashi, H., Matsunaga, T. (2014). Paraneoplastic syndromes associated with lung cancer. World journal of clinical oncology, 5(3), 197-223 DISCLOSURES: No relevant relationships by Matthew Ferrantino, source=Web Response No relevant relationships by Sandrine Hanna, source=Web Response No relevant relationships by Tala Salem, source=Web Response