title: Radiation effects on uptake of 99Tcm-hexamethylpropylen amine oxime (HMPAO) in head and neck tumours.
abstract: Twenty patients with malignant head and neck tumours were imaged with 99Tcm-labelled hexamethylpropylene amine oxime (HMPAO), a radiopharmaceutical generally used for blood flow studies. Before radiotherapy (RT), 93% of the tumours could be detected with single photon emission computed tomography (SPECT) and 45% with planar imaging. Whole tumour-to-background 99TcmHMPAO uptake ratios ranged from 3.6 to 1.0 (mean 1.7 +/- 0.6) in untreated tumours. There was a good correlation between tumour volume and uptake (r = 0.69, P = 0.002). Sixteen patients were reimaged during or shortly after radical RT. 99TcmHMPAO uptake was significantly lower after treatment (mean uptake ratio 1.2 +/- 0.3, P less than 0.001). However, RT associated changes in 99TcmHMPAO uptake were in agreement with the clinical response in only 63% of the studies. This study indicates that 99TcmHMPAO SPECT imaging can be used for pretherapeutic localisation of head and neck tumours. Although most tumours show a decrease in uptake after irradiation the poor association with tumour regression does not allow for reliable assessment of treatment response.
authors.affiliation: Department of Oncology and Radiotherapy, Turku University Central Hospital, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Minn
authors.forename: A
authors.initials: A
authors.lastname: Ahonen
authors.forename: R
authors.initials: R
authors.lastname: Paul
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006258:Head and Neck Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000532:radiotherapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds / Q000378:metabolism*; D010091:Oximes / Q000378:metabolism*; D011877:Radionuclide Imaging; D019690:Technetium Tc 99m Exametazime
chemical_list: D015609:Organotechnetium Compounds; D010091:Oximes; D019690:Technetium Tc 99m Exametazime