Note the lobulated appearance. The pearly-white tissue is cartilage. The more translucent areas are loose, myxoid tissue. The surface has been inked to indicate surgical margins. They develop as nodular endobronchial or bronchiolar growths covered by non-neoplastic epithelium.
Parenchymal tumors tend to have more epithelial clefts than do endobronchial tumors.
Here, the connective tissue has a myxoid appearance defined by the abundant bluish matrix. In any case, the results of FNA or biopsies should be correlated with clinical and radiographic findings. FNA of a solitary pulmonary nodule showed this fragment of cartilage as well as fibromyxoid tissue as shown below. This loose, connective tissue and the cartilage above both stain with antibody to S-100 protein, which can be helpful in diagnosis. Although almost always benign, one patient with a tumor of 37 years' duration had apparent malignant sarcomatous change after resection of a 12 cm tumor.