MEDizzy - A 69-year-old woman has had a chronic cough for the past

Feed Library Learning Discuss Leaderboard Journal

Cellular Pathology

A 69-year-old woman has had a chronic cough for the past year. A chest radiograph shows a 6 cm mass in the left lung. A needle biopsy specimen of the mass shows carcinoma. A pneumonectomy is performed, and examination of the hilar lymph nodes reveals a uniform, dark black cut surface. Which of the following factors most likely accounts for the appearance of these lymph nodes?

ExplanationLung and hilar lymph nodes accumulate anthracotic pigmentation when carbon pigment is inhaled from polluted air. The tar in cigarette smoke is a major source of such carbonaceous pigment. Older individuals generally have more anthracotic pigment, but this is not inevitable with aging—individuals living in rural areas with good environmental air quality have less pigment. Resolution of hemorrhage can produce hemosiderin pigmentation, which imparts a brown color to tissues. Hepatic failure may result in jaundice, characterized by a yellow color in tissues.