Technetium(99mTc) Human Serum Albumin Diethylenetriamine Pentaacetic Acid

It has been well-known that technetium-99m-human serum albumin-diethylenetriaminepenta-acetic acid (99mTc-HSAD) scintigraphy is useful for diagnosis of the localization of the gastrointestinal arterial or venous bleeding. In this report, we describe a case of venous bleeding from capillary hemangioma of the ileum end detected by 99mTc-HSAD scintigraphy. This patient was a 9-year-old girl with severe anemia. Gastrointestinal bleeding was suspected from her clinical course and laboratory tests. Immediately after melena occurred, 99mTc-HSAD scintigraphy showed the extravasation of RI suggesting gastrointestinal bleeding in the ileum end. Abdominal angiography immediately after 99mTc-HSAD scintigraphy, however, could not show the extravasation of contrast agent. Because the condition of the patient became worse, laparotomy was performed on the basis of 99mTc-HSAD scintigraphy findings. At surgery, venous bleeding from capillary hemangioma in the ileum end was observed. It was suggested that 99mTc-HSAD scintigraphy was very useful for identifying the gastrointestinal venous bleeding.

Sentinel node biopsy (SNB) in breast cancer is a promising surgical technique that avoids unnecessary axillary lymph node dissection. To optimize lymphatic mapping with radiopharmaceuticals, mammary lymphoscintigraphy with 30-50 MBq of technetium-99m-diethylenetriamine pentaacetic acid human serum albumin (99mTc-HSAD), technetium-99m-human serum albumin (99mTc-HSA), or technetium-99m-tin colloid (99mTc-TC) were investigated in 69 cases of primary breast cancer. Dynamic early images were obtained during the first 30 or 40 minutes, and static delayed images were obtained 6 hours after tracer injection. Hot spots as sentinel lymph nodes (SLNs) appeared in 51 of 69 cases (74%): in early images in 27 cases and in delayed images in 24 cases. SLNs were visualized more frequently in 23 of the 26 cases (88%) treated with 99mTc-HSAD and in 21 of the 24 cases (88%) treated with 99mTc-HSA than in only 7 of the 19 cases (37%) treated with 99mTc-TC. In 26 of the 51 cases, SLNs were identified as faint spots in delayed images. There was a significant difference in the first appearance of SLNs on the lymphoscintiscan between 43 cases of dense breast parenchyma and 26 cases of fatty breast parenchyma. These results suggest that 99mTc-HSAD or 99mTc-HSA is acceptable for lymphatic mapping, but in cases which have faint spots in delayed images or fatty breast parenchyma, gamma probe-guided SNB may result in failure or misleading false-negative SLNs.