Same case with formation of interstitial granulomas. Non-caseating granuloma in sarcoidosis. Calcified circular bodies of various kinds can be seen in sarcoidosis. Lipid pneumonia, with large, circular spaces that previously contained lipid. This was due to aspiration of mineral oil.
Polarized light shows talc particles in blood vessels and interstitium.
Pulmonary infiltrates in main-line drug user. The bronchial mucosa at left is normal. Stratified squamous metaplastic epithelium heaps up at right. The mucosa is completely occupied by malignant squamous cells with large, hyperchromatic nuclei. Prickles are seen between cells.