A 56-year-old woman comes to the office due to 4 months of mild cough with occasional, scant sputum production. Yesterday, she noticed blood in her sputum. The patient has no chronic medical conditions. She has never smoked or used illicit drugs but drinks alcohol socially. Vital signs and pulmonary examination are normal. Chest x-ray reveals a 2.5-cm irregular nodule in the peripheral right upper lung field with no hilar or mediastinal lymph node enlargement. What is the most likely diagnosis in this patient?

Question

A 56-year-old woman comes to the office due to 4 months of mild cough with occasional, scant sputum production.  Yesterday, she noticed blood in her sputum.  The patient has no chronic medical conditions.  She has never smoked or used illicit drugs but drinks alcohol socially.  Vital signs and pulmonary examination are normal.  Chest x-ray reveals a 2.5-cm irregular nodule in the peripheral right upper lung field with no hilar or mediastinal lymph node enlargement.  What is the most likely diagnosis in this patient?

Quizplus · Accepted Answer

11ec25c8_d4b9_4068_bc81_61ffbe19dd91_MD0003_00 This patient's long-standing cough, hemoptysis, and large, irregular pulmonary nodule raise strong suspicion for lung cancer. Although smoking is the single greatest risk factor for lung cancer in all patient populations, ~50% of women who develop lung cancer are never-smokers (generally defined as <100 lifetime cigarettes). Risk is increased with exposure to secondhand smoke, radon, environmental carcinogens (eg, asbestos, chromium, arsenic), or oncogenic viruses (eg, human papillomavirus). Chronic lung disease and previous chemotherapy/radiotherapy also increase risk. The most common type of lung cancer in never-smokers is adenocarcinoma, which typically arises in the lung periphery. Patients frequently have chest pain or pleural effusion (eg, dyspnea) due to erosion of the tumor into surrounding structures. Hemoptysis and cough also frequently occur, particularly as the tumor grows. In contrast, patients who smoke most often develop squamous cell carcinoma, which usually occurs in the central portion of the lung rather than in the periphery (Choice D). (Choice B) Histoplasmosis is a mycosis endemic to the Ohio and Mississippi river valleys that usually causes asymptomatic infection. However, a minority (~5%) of patients develop lobar infiltrate, hilar lymphadenopathy, and systemic symptoms (eg, fever). The presence of a peripheral lung nodule with no infiltrate or hilar lymphadenopathy makes histoplasmosis unlikely. (Choice C) Sarcoidosis can cause chronic cough and (rarely) hemoptysis. However, most patients have significant bilateral hilar adenopathy. The presence of a solitary peripheral mass would be atypical. (Choice E) Although active tuberculosis often causes cough and hemoptysis, patients generally have systemic manifestations (eg, weight loss, fever). Chest imaging usually shows hilar adenopathy and a cavitary/patchy lung infiltrate. A solitary, irregular nodule in the lung periphery would be atypical. Educational objective: Smoking is the single greatest risk factor for lung cancer in all patient populations. However, ~50% of women who develop lung cancer have no history of smoking. Women who have never smoked most often develop adenocarcinoma, which usually arises in the lung periphery. References: Non-small cell lung cancer in never smokers as a representative 'non-smoking-associated lung cancer': epidemiology and clinical features. (http://www.ncbi.nlm.nih.gov/pubmed/21562939)

A 56-Year-Old Woman Comes to the Office Due to 4