Using a continuous transformation of the Breslow thickness for prognosis in cutaneous melanoma

Citation
Rt. Vollmer et Hf. Seigler, Using a continuous transformation of the Breslow thickness for prognosis in cutaneous melanoma, AM J CLIN P, 115(2), 2001, pp. 205-212
Citations number
67
Categorie Soggetti
Research/Laboratory Medicine & Medical Tecnology","Medical Research Diagnosis & Treatment
Volume
115
Issue
2
Year of publication
2001
Pages
205 - 212
Database
ISI
SICI code
Abstract
Although the Breslow thickness provides the most important histologic infor mation for prognosis in cutaneous melanoma, controversies and uncertainty r emain about how best to use thickness. It is unclear whether cutpoints shou ld be used, or if they are used, which are optimal. We studied new data col lected from more than 1, 000 patients followed up for a relatively long per iod. From Cox proportional hazards models of survival we learned that more cut points provide more prognostic information than using, for example, jus t I cutpoint at 1.7 mm. Nevertheless, a continuous transformation provides an effective alternative that captures the information that thickness provi des, and it avoids the pitfalls of using multiple cutpoints. In a multivari ate model, this transformation provided strong prognostic information, and the result produced a prognostic score for cutaneous melanoma. This score p rovides a practical way that Cox model results can be used, and we believe it consolidates the prognostic information provided by traditional histolog ic and clinical variables. When newer prognostic variables are introduced, we suggest that they be used with this continuous transformation of thickne ss rather than with cutpoints in thickness.