Table 2.

Key Pathological Features of Sarcoidosis

Favors Sarcoidosis	Against Sarcoidosis
Granuloma presence
Numerous	Few
Absent but with nodular hyalinized fibrosis representing healed granulomas (scattered multinucleated giant cells may be detectable)	Absent
Granuloma morphology
Compact, tightly formed collections of large “epithelioid” histiocytes and multinucleated giant cells. Granulomas tend to stay discrete	Loosely organized collections of mononuclear phagocytes/multinucleated giant cells
Nonnecrotic or focal and usually minimal ischemic necrosis	• Extensive necrosis
	• Dirty necrosis (containing nuclear debris)
	• Palisading granulomas
Fibrosis beginning at the granuloma periphery with extension centrally into the granuloma, with or without calcification
Lesion location
Perilymphatic; around bronchovascular bundles and fibrous septa containing pulmonary veins, and near visceral pleura	• Lack of lymphangitic distribution
	• Intraalveolar granulomas
In necrotizing sarcoid angiitis and granulomatosis: granulomatous angiitis with invasion of vascular walls
Accompanying histology
Sparse surrounding lymphocytic infiltrate	• Robust surrounding inflammatory infiltrate (including lymphocytes, neutrophils, eosinophils, and plasma cells)
	• Secondary lymphoid follicles
Microorganism stains and cultures
Negative	Positive
Multidisciplinary clinical features
Intra- and extrathoracic involvement	Extrathoracic involvement only