57Co-bleomycin imaging study of tumors of the head and neck

57Co-Bleomycin (57Co-BLM) was used to visualize malignancies of the head and neck because it does not present the disadvantages of many other radiopharmaceuticals. In a series of 21 patients with 9 control subjects and 12 cases of tumors, 57Co-BLM showed a high and rapid uptake in primary site and metastases of malignant tumors of various histologic types, but not in benign tumors such as angiofibromas. Compared to 67Ga-citrate, 57Co-BLM has many advantages for tumor imaging in the areas of nose, pharynx and larynx: No background activity due to the concentration of 57Co-BLM in normal structures of the head and neck has ever been observed, as opposed to what happens with 67Ga-citrate. Furthermore, the blood clearance of 57Co-BLM is much more rapid than that of 67Ga-citrate, so that an early study may be performed in a 6 to 24 hr interval instead of 48 to 72 hr with 67Ga-citrate. 57Co-BLM scintigraphy is an easy, non-invasive and sensible diagnostic technique in determining the extent of malignant tumors in ORL patients