Respiratory SystemThese well-aerated, pink normal lungs show the usual pattern with three lobes on the right and two lobes on the left. There is minimal dark anthracotic pigment.
This is normal lung microscopically. The alveolar walls are thin and delicate. The alveoli are well-aerated and contain only an occasional pulmonary macrophage (type II pneumonocyte).
the alveoli in this lung are filled with a smooth to slightly floccular pink material characteristic for pulmonary edema. Note also that the capillaries in the alveolar walls are congested with many red blood cells.
These lungs appear essentially normal, but are hyperinflated from air trapping in a patient who died with status asthmaticus.
Between the bronchial cartilage at the right and the bronchial lumen filled with mucus at the left is a submucosa widened by smooth muscle hypertrophy, edema, and inflammation (mainly eosinophils). These are changes of bronchial asthma, more specifically extrinsic asthma from type I hypersensitivity to allergens.
This is another form of obstructive lung disease known as bronchiectasis. Bronchiectasis occurs when there is obstruction or infection with inflammation and destruction of bronchi so that there is permanent dilation
EMPHYSEMA On cut section of the lung, the dilated airspaces with emphysema are seen. Although there tends to be some scarring with time because of superimposed infections, the emphysematous process is one of loss of lung parenchyma, not fibrosis.
Microscopically at high magnification, the loss of alveolar walls with emphysema is demonstrated. Remaining airspaces are dilated
Pneumoconiosis:A silicotic nodule in lung is seen here. It is composed mainly of bundles of interlacing pink collagen. There is a minimal inflammatory reaction.
The asbestos fiber becomes coated with iron and calcium, which is why it is often referred to as a "ferruginous body" as seen here with an iron stain
This is the causative agent for asbestosis. This long, thin object is an asbestos fiber
This is the microscopic appearance of diffuse alveolar damage (DAD) in the lung. there are hyaline membranes, as seen here, lining alveoli. Later, type II pneumonocyte proliferation and then interstitial inflammation and fibrosis are seen
Regardless of the etiology for restrictive lung diseases, many eventually lead to extensive fibrosis. The gross appearance, as seen here in a patient with organizing diffuse alveolar damage, is known as "honeycomb" lung because of the appearance of the irregular air spaces between bands of dense fibrous connective tissue.
The main changes are seen in the interstitium. Diffuse and progressive fibrous thickening of the alveolar walls leading to scarring and gross destruction of the lung, ending in “honeycomb lung”.
InfectionsThis is a lobar pneumonia in which consolidation of the entire left upper lobe has occurred.
A closer view of the lobar pneumonia demonstrates the distinct difference between the upper lobe and the consolidated lower lobe
MorphologyCongestion: gross: the lung is heavy and red.
Micro: vascular engorgement, intra-alveolar fluid and few neutrophils, numerous bacteria.
Red Hepatization: gross: red, firm and airless lobe with liver like consistency.
Micro: massive exudate, red cells, neutrophils, and fibrin filling the alveoli.
Gray Hepatizaiton: gross: grayish-brown colour with dull surface.
Micro: disintegration of RBCs, and persistence of Fibrinosuppurative exudate.
Resolution: digestion of exudate, into granular semifluid debris, resorbed and digested by macrophages or coughed up.
The pleura if involved either resolved or end with organization and fibrous thickening and adhesions.
Lobar Pneumonia – Gray hep…At the left the alveoli are filled with a neutrophilic exudate that corresponds to the areas of consolidation seen grossly with the bronchopneumonia. This contrasts with the aerated lung on the right of this photomicrograph
At higher magnification can be seen a patchy area of alveoli that are filled with inflammatory cells. The alveolar structure is still maintained, which is why a pneumonia often resolves with minimal residual destruction or damage to the lung.
The pleural surface left demonstrates thick yellow-tan purulent exudate and the pleural cavity is filled with purulent exudate. This is an empyema.
Seen here are two lung abscesses, one in the upper lobe and one in the lower lobe of this left lung. An abscess is a complication of severe pneumonia.
Here, alveolar walls are no longer visible because there is early abscess formation. There is also hemorrhage
lung abscess is seen on the right bordered by a thin wall of organizing granulation tissue. The center of the abscess contains neutrophils and necrotic debris.
This is a fungal granuloma produced by Aspergillus organisms. A fungus ball composed of blue-staining hyphal elements of Aspergillus is seen here in a bronchus.
This is a squamous cell carcinoma of the lung that is arising centrally in the lungSecond figuer is larger squamous cell carcinoma in which a portion of the tumor demonstrates central cavitation, probably because the tumor outgrew its blood supply
This is the microscopic appearance of squamous cell carcinoma with nests of polygonal cells with pink cytoplasm and distinct cell borders. The nuclei are hyperchromatic and angular.
This mass is a peripheral adenocarcinoma of the lung tend to arise more peripherally occurs more often in non-smokers and in smokers who have quit (with a much lower incidence than lung cancer in smokers).
Microscopically, adenocarcinoma is composed of columnar cells that proliferate along the framework of alveolar septae.
Arising centrally in this lung and spreading extensively is a small cell anaplastic (oat cell) carcinoma. The cut surface of this tumor has a soft, lobulated, white to tan appearance
This is the microscopic pattern of a small cell anaplastic (oat cell) carcinoma in which small dark blue cells with minimal cytoplasm are packed together in sheets
Here are two examples of a benign lung neoplasm known as a pulmonary hamartoma.The pulmonary hamartoma is seen microscopically to be composed mostly of benign cartilage on the right that is jumbled with a fibrovascular stroma and scattered bronchial glands on the left
A nest of metastatic infiltrating ductal carcinoma from breast is seen in a dilated lymphatic channel in the lung.
Here are larger but still variably-sized nodules of metastatic carcinoma in lung.
Morphology:The affected lung is typically ensheathed by a yellow-white, firm, sometimes gelatinous layer of tumor that obliterates the pleural space
The neoplasm may directly invade the thoracic wall or the subpleural lung tissue.
Distant metastasis is rare.
The dense white encircling tumor mass is arising from the visceral pleura and is a mesothelioma