FMISO-PET has demonstrated the ability to image and quantitate hypoxia. Tumor cells exhibiting hypoxia, a low-oxygen state, are more resistant to radiation therapy than adequately oxygenated tumor cells. Hypoxia is the one of the most important prognostic factors in cancer of the head and neck (HNC) and non–small cell lung cancer (NSCLC).
The study analyzed whether high FMISO uptake, which indicates hypoxia, correlates with tumor recurrence after radiotherapy and low uptake of FMISO, which indicates normal oxygenation, correlates with a longer survival rate. The research team presented its results on June 21 at the Society of Nuclear Medicine's 51st Annual Meeting in Philadelphia.
Thirty one patients--21 with advanced HNC and 10 with advanced NSCLC--were selected for the study prior to curative radiotherapy. FMISO-PET scans of each patient were acquired and analyzed; the patients then underwent radiotherapy. Data from clinical follow-up within one year were available for 19 patients.
The researchers found that high uptake of FMISO correlated with greater risk of tumor recurrence. They also found that a high ratio of uptake of FMISO by tumor tissue compared to uptake by muscle tissue correlated with a higher recurrence of tumor. According to Dr. Susanne M. Eschmann, MD, one of the authors of the study, "the combination of both of these results allows for a very precise prediction of therapeutic outcome."
"The results of our study can be applied to treatment," stated Dr. Eschmann. "Should this technique become standard practice--using FMISO-PET images to predict the possible recurrence of tumor--then treatment methods can correspond to prognosis. We believe that FMISO-PET represents a valuable tool for patient discrimination. Patients with increased risk of relapse may be introduced to an intensified therapeutic regimen."
The Society of Nuclear Medicine is holding its 51st Annual Meeting June 19–23, 2004, at the Pennsylvania Convention Center in downtown Philadelphia. Hot topics for the 2004 meeting include techniques for the early diagnosis of Alzheimer's disease; advanced imaging for the diagnosis, staging, and treatment of cancer; nuclear cardiology; and the collaboration between nuclear medicine and bioengineering in the fight against cancer.