The relationship between time to initiation of adjuvant chemotherapy and survival in breast cancer: a systematic review and meta-analysis

364 Background: The optimal timing from CRC surgery to initiation of AC is unknown. We report a systematic review and meta-analysis to determine the relationship between time to adjuvant chemotherapy (TTAC) and survival. Methods: A systematic review of literature was done to identify studies that described the relationship between TTAC and survival. Studies were only included if the distribution of relevant prognostic factors was adequately described, and either comparative groups were balanced or results adjusted for the prognostic factors. Hazard ratio (HR) and TTAC for overall survival (OS) and disease free survival (DFS) from each study were converted to a regression coefficient (β) and standard error (SE) corresponding to a continuous representation per 4 weeks of TTAC. The adjusted β from individual studies were combined using a fixed-effect model. Inverse-variance (1/SE2) was used to weight individual studies. The possible effect of publication bias was investigated using the trim and fill approach. Results: We identified 9 eligible studies involving 14,357 patients (4 published articles, 5 abstracts). Two studies were randomized trials and 7 were cohort studies. Six studies reported TTAC as a binary variable and 3 reported TTAC as ≥3 categories. An estimate of HR for OS was derived from all 9 studies and estimate for DFS was derived from 5 studies. Meta-analysis demonstrated that a 4-week increase in TTAC was associated with a significant decrease in both OS (HR = 1.12, 95% CI 1.09-1.15), and DFS (HR = 1.15, 95% CI 1.11-1.20). The analysis showed no significant heterogeneity among studies. These TTAC associations remained significant after analysis for potential publication bias, and when the analysis was repeated excluding the two studies of largest weight. Conclusions: This study demonstrates a 12% increase in the risk of death for each 4 week of delay in the start of AC for CRC. These findings indicate the need for clinicians and health systems managers to take the steps necessary to keep TTAC as short as reasonably achievable. In addition, our results suggest there may be some benefit to AC after a 3-month TTAC delay. No significant financial relationships to disclose.

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The relationship between serum vitamin D levels and breast cancer prognosis: A meta-analysis.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.1521 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. 1521-1521

Author(s):

April Ann Nicole Rose ◽

Christine Elser ◽

Pamela Jean Goodwin

Keyword(s):

Breast Cancer ◽

Systematic Review ◽

Vitamin D ◽

Clinical Outcomes ◽

Survival Data ◽

Fixed Effects ◽

Meta Analysis ◽

Serum Vitamin ◽

Vitamin D Levels ◽

The Relationship

1521 Background: Vitamin D (VitD) is a circulating hormone known to regulate gene transcription in breast cancer (BC) cells. The association between VitD and BC risk has been extensively studied. Until recently, however, the role of VitD in BC progression and its association with clinical outcomes among BC patients was poorly understood. To assess these new developments, a systematic review and meta-analysis was performed. Methods: A systematic review and meta-analysis by searching MEDLINE (1982 – 2012), ASCO, and SABCS for abstracts (2009 – 2012), with the following keywords: “breast cancer” and “prognosis” or “survival”, and “vitamin D” or ”calcitriol.” Abstracts were scrutinized for reports correlating serum VitD levels with breast cancer clinical outcomes, including: disease-free survival (DFS) and overall survival (OS). Studies were included if serum VitD samples were taken shortly after diagnosis and survival data were reported. Meta-analyses were performed using an inverse-variance weighted fixed-effects model. Results: We identified 7 studies reporting correlative data between serum VitD levels and BC survival. These data included 4,885 patients evaluated for DFS and 3858 patients evaluated for OS. VitD-deficiency was defined as <30ng/mL, <20ng/mL, and <14ng/mL in 3, 3, and 1 studies, respectively, and was identified in an average of 48.1% of patients (range: 17.9-87.8%). VitD deficiency was associated with a pooled hazard ratio (HR) of 2.13 (CI: 1.64 - 2.78) and 1.76 (CI: 1.35 - 2.30) for DFS and OS, respectively. Conclusions: To our knowledge, this is the first report of a meta-analysis of the relationship between serum VitD and BC prognosis. The prevalence of VitD-deficiency varied widely across studies and may reflect differences in geographic location, race, and rates of supplementation across patient populations. These findings support the hypothesis that VitD-deficient breast cancer patients have poorer clinical outcomes than VitD sufficient patients; but do not establish whether this relationship is causative. Further studies are warranted to investigate the possible protective effects of VitD supplementation on survival among VitD-deficient BC patients.

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