The mean ± SD plasma CCL18/PARC concentration and ChT activity in the five patients from Period 1 with an identified genetic cause for NP-C were 289 ± 286 ng/mL (range 88–788 ng/mL) and 380 ± 374 nmol/mL*h (range 156–1045 nmol/mL*h), respectively. This evidence concerns the gene CCL18 and nasopharyngeal carcinoma.