title: Nasopharyngeal carcinoma incidence in North Tunisia: negative trends in adults but not adolescents, 1994-2006.
abstract: Nasopharyngeal carcinoma (NPC) is the second most common neoplasm of head and neck in Tunisia. The distribution is bimodal with a first period occurrence between 15 and 20 years old and a second peak at around 50 years of age. Undifferentiated carcinoma of nasopharynx type III (UCNT) is the predominant histological type (93.4%). Data of cancer registry of North Tunisia confirmed that it is an intermediate risk area for NPC with overall ASRs of 3.6 and 1.6/100,000 respectively in males and females. This study aimed to present the evolution of incidence rate of nasopharyngeal carcinoma over a period of 12 years (1994-2006). Data of cancer registry of North Tunisia (NTCR), covering half of the Tunisian population, were used to determine evolution of NPC incidence, calculated by 5 year periods. The estimated annual percentage change (EAPC) was used as an estimate of the trend. To best summarize the behavior or the data trend across years, we used a join-point regression program. Between 1994 and 2006, we observed negative annual average change of standardized incidence in men and women (-3.3% and -2.7%) also for the standardized incidences which showed a rather important decline (26.4% in males and 22.3% in females). The truncated age standardized incidence rate of NPC in adults aged of 30 years old and more (N=1209) decreased by -0.4% per year from 1994 to 2006 over time in north Tunisia dropping from 6.09 to 4.14 person-years. However, the rate was relatively stable during this period among youths aged 0-29 years (N=233) in both sexes. NPC demonstrated a favorable evolution from 1994-2006 probably due to a improvement in socioeconomic conditions.
authors: Department of Epidemiology and Biostatistics, Salah Azaiez Institute of Oncology Cancer Registry North of Tunisia, Tunis, Tunisia E-mail : wided.benayoub@rns.tn.
authors: Ben Ayoub Hizem
authors: BA
authors: Wided
authors: Boussen
authors: B
authors: Hamouda
authors: Hsairi
authors: H
authors: Hamadi
authors: Ben Abdallah
authors: BA
authors: Mansour
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology*; D012042:Registries; D012306:Risk; D014416:Tunisia / Q000453:epidemiology; D055815:Young Adult