Improved evaluation of mediastinal lymph node metastasis in lung cancer with Ga-67 emission CT

To determine the contribution of single-photon emission CT (SPECT) to the evaluation of mediastinal lymph node metastasis of lung cancer with Ga-67, planar and SPECT imaging findings in 40 postoperative patients were analyzed. The images, obtained using Ga-67 citrate, were compared with postoperative histologic findings in the mediastinal lymph nodes. SPECT imaging yielded ten true-positive, 12 false-positive, four false-negative, and 14 true-negative studies. SPECT proved superior to planar imaging in depicting mediastinal lymph node metastasis, although the number of false-positive studies increased somewhat