Serum copper and zinc levels in patients with nasopharyngeal carcinoma.

Serum copper levels (SCL) and serum zinc levels (SZL) were evaluated in 103 patients with nasopharyngeal carcinoma (NPC) of varying stages during radiotherapy, and compared with normal subjects. Ninety-nine of these patients were undifferentiated squamous cell carcinoma, 2 were differentiated squamous cell carcinoma and 2 were moderately differentiated squamous cell carcinoma. The serum copper levels were significantly higher in NPC patients than in normal subjects, but the difference of SZL was not significant. The ratio of Cu/Zn also showed a significant difference between normal subjects and NPC patients. There was no significant difference in SCL, Cu/Zn or SZL between men and women. Patients with more advanced stages of the disease had more elevated Cu/Zn ratios. It appears that SCL in NPC patients may be useful in evaluating the extent of the disease; furthermore, the Cu/Zn ratio may also provide some information in discriminating between normal subjects and patients with early or advanced stages of NPC.