Prognostic factors in patients with nasopharyngeal carcinoma.

From 1971 to 1985 a total of 122 patients with non-distant metastatic nasopharyngeal carcinoma were treated at the Norwegian Radium Hospital with radiation doses that increased from 50 Gy (at 2 Gy/fractions) to 70 Gy (at 2 Gy/fractions) during the treatment period. Possible relationship between the increase in dose and survival time was investigated. The median cancer-specific survival time was 50 months, and the median crude survival time 38 months. No correlation was found between radiation dose and survival time. In a multivariate analysis histology was found to be the most important prognostic factor for survival with a relative risk of death from cancer of 3.4 and 3.2 for non-keratinizing carcinoma and squamous cell carcinoma respectively compared with undifferentiated carcinoma. When assessed in terms of N category the relative death risk for N2/N3 was 2.1 compared to N0/N1.