Assessment of mediastinal involvement in lung cancer with technetium-99m-sestamibi SPECT.

UNLABELLED: This study evaluated the clinical role of SPECT with sestamibi versus CT in the presurgical staging of lung cancer. METHODS: Forty-seven consecutive patients (44 men, 3 women; mean age 63.3 yr, range 49-82 yr) with clinical and radiological suspicion of lung cancer were enrolled in this study. Staging procedures including radiography, CT, fiberoptic bronchoscopy and sestamibi SPECT of the thorax. Radionuclide imaging was performed after intravenous injection of 740-925 MBq of sestamibi. In 36 patients a histological diagnosis was made, and these patients were evaluated for the study of mediastinal lymph node involvement. RESULTS: Mediastinal lymph node involvement was demonstrated in 11 of the 36 patients evaluated. Sestamibi SPECT correctly staged 10 of 11 patients with and 21 of 25 without mediastinal nodes, showing a diagnostic sensitivity of 91% and a specificity of 84%. Computed tomography gave 8 true-positive and 15 true-negative results, with a sensitivity of 73% and a specificity of 60%. Sestamibi SPECT results were also better than those of CT with regard to positive and negative predictive values and accuracy. CONCLUSION: The clinical role of sestamibi SPECT can be fully appreciated when the technique is used in selected patients, combined with CT or MRI, or both, to assess mediastinal involvement and avoid any invasive staging procedures.

Current role of gallium scan and magnetic resonance imaging in the management of mediastinal Hodgkin lymphoma.

BACKGROUND: A residual mediastinal mass after treatment represents a common diagnostic problem in the management of patients with Hodgkin lymphoma (HD). Conventional diagnostic radiology, computed tomography (CT), or ultrasonography (US) do not adequately reflect changes as fibrosis or necrosis. Gallium-67 (67Ga) imaging has been proven to be useful for the evaluation of HD in the mediastinum. The authors compared the ability of gallium scan and magnetic resonance imaging (MRI) to evaluate the mediastinal disease in the follow-up of patients with HD. METHODS: Thirty-four patients previously treated for HD were investigated with gallium scan, MRI, and all the other investigations to evaluate the mediastinal region. Sixteen patients were in restaging after treatment, and 18 were investigated for suspected radiologic recurrence in the mediastinum (follow-up, 9-75 months). The results of gallium scan and MRI were matched with clinical findings during the follow-up. RESULTS: A sensitivity of 85.7% for 67Ga and 92.8% for MRI was found, while the specificity was 100% for the scan and 80.6% for MRI. The predictive positive value that resulted was 100% for 67Ga and 68.4% for MRI. CONCLUSIONS: Both examinations were accurate in assessing the activity of residual masses in the mediastinum after treatment. 67Ga showed a lower sensitivity in comparison with MRI, but 67Ga frequently overestimates the presence of pathologic tissue. The authors acknowledge the complementary role of these two tests, but if only one of these examinations can be performed for logistic or economic reasons, then gallium scan represents the single most adequate diagnostic procedure.