[Lymphoscintigraphy with 99mTc-DTPA-HSA: detection of metastases to iliopelvic lymph nodes].

The purpose of this study was to evaluate 99mTc-DTPA-HSA as an iliopelvic lymphoscintigraphic agent in 5 normal volunteers and 10 patients with metastases of malignant tumors (cancer, 9; and malignant lymphoma, 1) to the iliopelvic lymph nodes. The subjects underwent intradermal injection of 185 MBq of 99mTc-DTPA-HSA into digital web spaces of the feet. Massage was applied at the injection sites for 30 sec; the subjects then walked around for 2 min. Whole-body scintigrams were obtained 5 min after injection. The whole-body scanning speed was 20 cm/min. The tracer transport was prompt. Within 15 min after injection, the tracer reached the termination of the thoracic duct in all normal volunteers. Normal whole-body images of excellent quality delineated the lymph nodes and channels almost without background radioactivity. The images of 9 patients with metastases of cancer showed clearly the following abnormal patterns: a) obstruction of lymphatic system (5/9, 55.6%); b) absence of visualization of the thoracic duct (44.4%); c) decreased uptake in lymph nodes (88.9%); d) visualization of collateral circulation (44.4%); e) tracer extravasation into more proximal soft tissue (22.2%). The image in the patient with malignant lymphoma showed increased uptake in the enlarged lymph nodes in addition to the all abnormal findings mentioned above. We concluded that 99mTc-DTPA-HSA is an excellent radiopharmaceutical for iliopelvic lymphoscintigraphy.