TRUST YOUR INSTINCTS: DIAGNOSTIC DIFFICULITIES OF ADVANVED LUNG CANCER IN A YOUNG MALE

Abstract

TOPIC: Lung Cancer TYPE: Fellow Case Reports INTRODUCTION: Lung cancer remains the leading cause of cancer-related death in the United States, occurring at the highest rate in those aged over 70yrs(1). It is exceedingly rare for those under the age of 40 to be diagnosed with primary lung cancer, with an incidence of 0.6-4.6%(2). The low incidence of lung cancer in this age group can lead to diagnostic delay. We present a case of a 28 yr old male who was diagnosed with stage 4 lung adenocarcinoma after multiple ED and hospital visits. CASE PRESENTATION: A 28 yr old previously healthy male presented to our facility for evaluation of an 8wk history of shortness of breath and non-productive cough. Denied fevers, chills, malaise or myalgias. He stopped working for a car repossession company due to being too dyspneic to walk short distances. Social history is notable for social smoking and vaping but none in the 3 months prior to symptom onset. Denied recent travel or exposures. No relevant family history. He was previously seen at two outside facilities and thought to have an atypical pneumonia. No improvement after two courses of antibiotics, prednisone and trilogy inhaler. After an abnormal chest CT he was seen by an outside pulmonologist and cardiothoracic surgeon for biopsy but it was felt to not be indicated. He sought another opinion at our facility because he felt like something was being missed. A chest CT revealed an extensive central infiltrative masslike consolidation encasing the right main pulmonary artery with extensive interstitial thickening and diffuse nodular pattern throughout the right lung with mediastinal adenopathy. Left lung appeared normal. The outside facility chest CT from a few weeks prior was obtained for comparison. This showed similar findings but the central masslike consolidation was now more extensive and confluent. Biopsy confirmed metastatic lung adenocarcinoma. DISCUSSION: A recent review of lung cancer in those 35yrs and younger found that nearly half of these patients had metastatic disease at presentation(3). The reason for advanced stage at diagnosis in this age group has yet to be delineated. In this case, it is likely that at least one cognitive bias contributed to his diagnosis being delayed. Both ascertainment bias, where a physician's thinking is shaped by prior expectation and representativeness restraint which drives the diagnostician toward looking for prototypical manifestations of disease(4), likely contributed. When age is removed from the equation, his imaging alone would have prompted a biopsy during his earlier encounters. CONCLUSIONS: Illness scripts are an important part of diagnostic reasoning, but it is imperative that clinicians remain wary of potential cognitive biases which may put them at risk for diagnostic error. Relying too heavily on pattern recognition as in representativeness restraint, we risk missing atypical variants of disease such as lung cancer in young man. REFERENCE #1: U.S. Cancer Statistics Working Group. U.S. Cancer Statistics Data Visualizations Tool, based on 2019 submission data (1999-2017): U.S. Department of Health and Human Services, Centers for Disease Control and Prevention and National Cancer Institute; www.cdc.gov/cancer/dataviz, released in June 2020. REFERENCE #2: Pan, X., Lv, T., Zhang, F. et al. Frequent genomic alterations and better prognosis among young patients with non-small-cell lung cancer aged 40 years or younger. Clin Transl Oncol 20, 1168–1174 (2018). https://doi.org/10.1007/s12094-018-1838-z REFERENCE #3: Liu B, Quan X, Xu C, et al. Lung cancer in young adults aged 35 years or younger: A full-scale analysis and review. J Cancer. 2019;10(15):3553-3559. Published 2019 Jun 9. doi:10.7150/jca.27490 DISCLOSURES: No relevant relationships by Katie Baxter, source=Web Response