Selection of a high-level physician may help improve outcomes of nasopharyngeal carcinoma

Abstract

Background: To assess the relationship between the level of clinical radiation oncologist and the prognosis of patients with nasopharyngeal carcinoma (NPC). To our knowledge, no previous study has explicitly assessed the relationship with cancer prognosis and clinical radiation oncologists level. The effect of physicians on the prognosis has been entirely ignored.

Methods: Clinical data were collected for 1140 patients with newly diagnosed NPC. Based on the 3-year overall survival, the treating physicians were classified into 3 grades: high-level group, medium-level group, and low-level group. Cox proportional hazards regression analysis was used to assess the independent significance of different prognostic factors. Propensity score matching (PSM) was used to minimize the influence of confounders so that difference in outcomes provides an unbiased estimate of the influence of physician. Interactive Risk Attributable Program (IRAP) was used to calculate the attribution risk of individual risk factors or a combination of multiple factors.

Results: The 3-year OS in the high-level, medium-level, and low-level groups was 92.9%, 87.7%, and 83.5%, respectively (p = 0.003). After propensity score matching, the 3-year OS was 92.4%, 87.4%, and 82.9%, respectively (p = 0.004). IRAP was used to calculate the attribution risk of mortality risk. After multivariable adjustment, patient-related factors including tumor accounted for 90.02% [95% confidence interval (CI), 73.43-96.84%) and physician factors accounted for 17.66% (95% CI, 5.39-44.65%) of the mortalityrisk. All related factors, including patient-related factors and physician factors accounted for 92.02% (95% CI, 77.83-97.43%).

Conclusion: Our study demonstrated obvious differences in the prognosis of patients treated by various clinical radiation oncologists. The largest share of prognosis risk was found to be at the patient level, while variation in prognosis was, in part, attributable to differences among physicians.

Keywords: Intensity-modulated radiation therapy; Interactive Risk Attributable Program; Nasopharyngeal carcinoma; Physician level; Prognosis; Propensity score matching.