Concentrations of 5-FU in the tissues of the patients with oral cancer after administration of fluoropyrimidine derivative (SF-S)

Thirty two patients with oral cancers were orally administered 600-800mg/day of SF-S which contains sustained release granules of tegafur before operation. Tegafur and 5-FU concentrations in serum, submandibular lymph nodes, normal and cancerous tissues were evaluated after SF-S administration by the method of chemical assay using HPLC and GC-MS.The mean tegafur concentrations in serum, submandibular lymph nodes, and normal and cancerous tissues were 15.1μg/m/, 9.91μg/g, 9.52μg/g, and 9.84μg/g, respectively. The mean tegafur concentration in serum was significantly higher than that in the other tissues (p<0.001). The mean 5-FU concentrations in serum, submandibular lymph nodes, and normal and cancerous tissues were 22.5 ng/m/, 171.9ng/g, 44.0ng/g and 173.9ng/g, respectively. The mean 5-FU concentration in cancerous tissues was much higher than 50ng/g which was reported to be the minimum effective concentration, and significantly higher than that in serum and normal tissues (p<0.001). Besides, the mean 5-FU concentration in submandibular lymph nodes was similarly higher than that in serum and normal tissues (p<0.01). With regard to the locations of cancerous tissue, the mean 5-FU concentrations in cancerous tissues of maxillary gingiva, mandibula gingiva, tongue, buccal mucosa, and oral floor were 158.8ng/g, 309.7ng/g, 94.1ng/g, 95.2ng/g, and 348.2ng/g, respectively. The mean 5-FU concentration in cancer tissues of mandibular gingiva was significantly higher than those of tongue and buccal mucosa (p<0.05).In conclusion, these results suggest that SF-S could also be effective against oral cancer.