Technetium-99m HMPAO and SPECT in the assessment of blood flow in human lung tumours.

In order to assess the blood flow patterns through human lung tumours, 20 patients received 400-750 MBq 99TcmHMPAO intravenously 10 min before single photon emission computed tomography (SPECT). Ratios of uptake in the whole tumour relative to normal lung ranged from 0.35 to 1.53 (mean 1.01) with eight tumours showing less uptake than normal lung and ten showing greater uptake. In one patient the tumour was not distinguishable from surrounding lung and in another a large pleural effusion prevented evaluation. Tumour: lung ratios for central tumour regions ranged from 0 to 1.83 (mean 0.80) with 13 showing lower uptake than normal lung and five showing greater uptake. Duplicate scans were performed in eight patients demonstrating satisfactory reproducibility. This technique provides a simple and reproducible method for the assessment of tumour blood flow.