Familial and sporadic cases of nasopharyngeal carcinoma in Taiwan

Background Nasopharyngeal carcinoma (NPC) has a striking geographic/ethnic distribution with especially high rates among southern Chinese. Previous st udies have indicated that a family history of NPC is associated with increa sed risk and noted familial clustering in low-risk populations Materials an d Methods: We investigated differences between sporadic and familial cases of NPC in a case-control study, of 375 histologically confirmed NPC cases ( 99% response late) and 328 age-, sex-, and geographically-matched controls (88% response rate). All participants answered a derailed risk factor inter view and donated blood for EBV and CYP 2E1 testing Results: Subjects with a first degree relative with NPC had an odds ratio (OR) of 7.6 (95% confiden ce interval (CI) =2.3-25), while those with a family history of any other c ancer had only a slightly elevated risk of disease (OR=1.4; 95% CI=.93-2.2) . Of the cases, 25 (6.7%) were familial-having at least one first degree re lative with NPC. No significant difference was seen between familial and sp oradic cases with respect to sex, age, ethnicity, histology or stage. There was a nonsignificant (p =0.16) increase in TIN2 tumors among familial case s, suggesting a more aggressive tumor. Family history of other cancers, EBV serologies, or the distribution of the Rsal c2 form of the allele of cytoc hrome P450 2E1 were also not significantly different between the two groups . Conclusions: In conclusion, while genetic factors ale likely to play an i mportant role in NPC pathogenesis, our results provide little evidence that a familial form of NPC exists with characteristics notably distinct from s poradic cases.