succimer and Nasopharyngeal-Neoplasms

Twenty-seven patients (24 men, 3 women; ages: 39-74 years) were diagnosed as having squamous cell carcinoma of the nasopharynx (NPC) as confirmed by pathologic findings of biopsies. In addition, three of the 27 patients had metastases to neck lymph nodes. The results of 2-4-hour SPECT images of the head and neck after intravenous injection of 15-20 mCi of Tc-99m (V) DMSA were compared with normal Tc-99m (V) DMSA images and CT of heads and necks. The results showed that of the 27 NPC cases, none of the patients had a significant uptake of Tc-99m (V) DMSA. However, in the three cases complicated with metastases of neck lymph nodes, the metastatic lesions could be detected by Tc-99m (V) DMSA. Our results challenge previous reports in which carcinomas of the head and neck were detected by Tc-99m (V) DMSA. The tumor-seeking agent Tc-99m (V) DMSA is not a good choice for the detection of NPC among malignancies of the head and neck.

Topics: Adult; Aged; Carcinoma, Squamous Cell; Female; Humans; Lymphatic Metastasis; Male; Middle Aged; Nasopharyngeal Neoplasms; Organotechnetium Compounds; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid; Tomography, Emission-Computed, Single-Photon

We prepared 99mTechnetium(V) DMSA (pentavalent form) as an imaging agent for eighteen patients with proven nasopharyngeal carcinoma. The head, neck, chest and abdomen were scanned. The nasopharyngeal tumour showed tracer accumulation in only 5 out of the 18 patients (28%). The study indicates that 99mTechnetium(V) DMSA is not a useful radiopharmaceutical for visualising nasopharyngeal tumours although it may have other useful properties.

Topics: Carcinoma, Squamous Cell; Female; Humans; Lung Neoplasms; Lymphatic Metastasis; Male; Nasopharyngeal Neoplasms; Organometallic Compounds; Radionuclide Imaging; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

Being aware of the ideal nuclear properties of Tc-99m, our interest has been focused on the design of the (+5) oxidation state Tc-99m(V) dimercaptosuccinic acid (Tc(V)-DMSA) as a tumor-seeking agent. Tc-99m(V) DMSA holds a TcO4(3-) core and, like PO4(3-), has excellent characteristics for tumor uptake, but has a different distribution than the well-known renal scanning agent, Tc-99m DMSA. The differences in chemical behavior of Tc-99m(V) DMSA and Tc-99m DMSA are discussed. Three cases in which neoplasms were studies with Tc-99m(V) DMSA and Tc-99m DMSA are presented. Tc-99m DMSA and Tc-99m(V) DMSA, having a common ligand and tracer but, with the metal ion core in a different oxidation state, the uptake characteristics are altered markedly.

Topics: Adrenal Gland Neoplasms; Carcinoma, Renal Cell; Humans; Kidney Neoplasms; Male; Middle Aged; Nasopharyngeal Neoplasms; Neoplasms; Radionuclide Imaging; Succimer; Sulfhydryl Compounds; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid