Time-varying prognostic effects of primary tumor sidedness and grade after curative liver resection for colorectal liver metastases.
Surg Oncol
; 38: 101586, 2021 Sep.
Article
em En
| MEDLINE
| ID: mdl-33933898
ABSTRACT
BACKGROUND:
The veracity of the proportional hazards (PH) requirement is rarely scrutinized in most areas of cancer research, although fulfilment of this assumption underpins widely-used Cox survival models. We sought to critically appraise the existence of prognostic factors with time-dependent effects and to characterize their impact on survival among CLM patients.METHODS:
Consecutive patients who underwent liver resection with curative intent for CLM at the Singapore General Hospital were identified from a prospectively-maintained database. We evaluated PH of 55 candidate variables, and parameters which departed significantly from proportionality were included in Cox models that incorporated an interaction term to account for time-dependent effects. As sensitivity analyses, we fitted Weibull mixture 'cure' models to handle long plateaus in the tails of survival curves, and also analyzed the restricted mean survival time.RESULTS:
318 consecutive patients who underwent curative liver resection for CLM between Jan 2000 and Nov 2016 were included in this analysis. Hazard ratios for tumor grade (poorly-versus well- and moderately-differentiated) were found to decrease from 3.135 (95% CI 1.637-6.003) at 12 months to 2.048 (95% CI 1.038-4.042) after 24 months, and ceased to be significant at 26 months. Compared to left-sided tumors, a right-sided tumor location was found to portend worse prognosis for the first 10 months after resection but subsequently confer a survival benefit due to a crossing of survival curves. Corroborating this observation, long-term cure fractions were estimated to be 25.5% (95% CI 17.4%-33.6%) and 34.2% (95% CI 17.4%-50.9%) among patients with left-sided and right-sided primary disease respectively.CONCLUSION:
Primary tumor sidedness and grade appear to exert time-varying prognostic effects in CLM patients undergoing curative liver resection.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Colorretais
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Hepatectomia
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Neoplasias Hepáticas
Tipo de estudo:
Observational_studies
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Prognostic_studies
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article