Fig. 3

Immunohistochemical staining of primary cytokeratin-positive interstitial reticulum cell (CIRC) tumors, relapsed CIRC tumors and small cell lung carcinoma using CAM5.2, AE1/AE3, TTF-1, chromogranin A, synaptophysin, CD56, l-caldesmon, prolyl 4-hydroxylase 1 and transglutaminase II antibodies. Tumor cells of primary CIRC tumors and relapsed CIRC tumors were positive for CAM5.2 and AE1/AE3 and negative for TTF-1. Tumor cells of small cell lung carcinoma were focally positive for CAM5.2 and AE1/AE3 and weakly positive for TTF-1. Tumor cells of primary CIRC tumors and relapsed CIRC tumors were negative for chromogranin A, synaptophysin and CD56. Tumor cells of small cell lung carcinoma were focally positive for chromogranin A and strongly positive for synaptophysin and CD56. Tumor cells of primary CIRC tumors and relapsed CIRC tumors were positive for l-caldesmon, prolyl 4-hydroxylase 1 and transglutaminase II. Tumor cells of small cell lung carcinoma were negative for l-caldesmon, prolyl 4-hydroxylase 1 and transglutaminase II