201Tl chloride single photon emission computed tomography in patients with oral cavity squamous cell carcinoma

IN SQUAMOUS CELL CARCINOMA (SCC), some authors have reported that tumor angiogenesis is a prognostic factor in predicting the effect of treatment.1,2 There are some studies using microvessel density (MVD) in evaluating angiogenesis and showing the usefulness of MVD in predicting radiosensitivity in esophageal cancer,3 cervix carcinoma,4 and head and neck carcinoma.5–8 Furthermore, some authors used CD31 antibody and reported its usefulness in staining vascular endothelial cells.3,5,7,9 On the other hand, in evaluating the effectiveness of radiotherapy, some authors have reported the usefulness of 201Tl chloride single photon emission computed tomography (Tl SPECT) in brain tumor,10–12 lung cancer,13–16 bone and soft tissue sarcoma17 and head and neck cancer,18–22 because 201Tl chloride (Tl) has a tendency to accumulate in lesions with tumor activity.23 Nakahara et al.24 examined the percent decrease in the quantitative value using Tl SPECT after preoperative chemoradiotherapy (%Dtl) for advanced esophageal SCC. They reported that in evaluation using %Dtl, there was a Correlation between angiogenesis and reduction ratio measured using 201Tl chloride single photon emission computed tomography in patients with oral cavity squamous cell carcinoma