ORIGINAL CONTRIBUTIONS |
Repeated Occurrence of Basal Cell Carcinoma of the Skin and Multifailure Survival Analysis: Follow-up Data from the Nambour Skin Cancer Prevention Trial
1 Population Studies and Human Genetics, Queensland Institute of Medical Research, Royal Brisbane Hospital, Brisbane, Queensland, Australia
2 The Australian Centre for International and Tropical Health and Nutrition, University of Queensland, Brisbane, Queensland, Australia
Correspondence to Nirmala Pandeya, Queensland Institute of Medical Research, P.O. Royal Brisbane Hospital, Brisbane, Queensland 4029, Australia (e-mail: Nirmala.Pandeya{at}qimr.edu.au).
The aim of this study was to apply multifailure survival methods to analyze time to multiple occurrences of basal cell carcinoma (BCC). Data from 4.5 years of follow-up in a randomized controlled trial, the Nambour Skin Cancer Prevention Trial (1992–1996), to evaluate skin cancer prevention were used to assess the influence of sunscreen application on the time to first BCC and the time to subsequent BCCs. Three different approaches of time to ordered multiple events were applied and compared: the Andersen-Gill, Wei-Lin-Weissfeld, and Prentice-Williams-Peterson models. Robust variance estimation approaches were used for all multifailure survival models. Sunscreen treatment was not associated with time to first occurrence of a BCC (hazard ratio = 1.04, 95% confidence interval: 0.79, 1.45). Time to subsequent BCC tumors using the Andersen-Gill model resulted in a lower estimated hazard among the daily sunscreen application group, although statistical significance was not reached (hazard ratio = 0.82, 95% confidence interval: 0.59, 1.15). Similarly, both the Wei-Lin-Weissfeld marginal-hazards and the Prentice-Williams-Peterson gap-time models revealed trends toward a lower risk of subsequent BCC tumors among the sunscreen intervention group. These results demonstrate the importance of conducting multiple-event analysis for recurring events, as risk factors for a single event may differ from those where repeated events are considered.
carcinoma, basal cell; epidemiologic methods; neoplasms, multiple primary; proportional hazards models; skin neoplasms; survival analysis
Abbreviations: BCC, basal cell carcinoma
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  A. C. Green and G. M. Williams Point: Sunscreen Use Is a Safe and Effective Approach to Skin Cancer Prevention Cancer Epidemiol. Biomarkers Prev., October 1, 2007; 16(10): 1921 - 1922. [Full Text] [PDF]
|
|
|
|
|
|
J. C. van der Pols, G. M. Williams, N. Pandeya, V. Logan, and A. C. Green Prolonged Prevention of Squamous Cell Carcinoma of the Skin by Regular Sunscreen Use Cancer Epidemiol. Biomarkers Prev., December 1, 2006; 15(12): 2546 - 2548. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. C. van der Pols, C. Xu, G. M. Boyle, P. G. Parsons, D. C. Whiteman, and A. C. Green Expression of p53 Tumor Suppressor Protein in Sun-exposed Skin and Associations with Sunscreen Use and Time Spent Outdoors: A Community-based Study Am. J. Epidemiol., June 1, 2006; 163(11): 982 - 988. [Abstract] [Full Text] [PDF]
|
|