Page 61 - Predicting survival in patients with spinal bone metastasesL

metastases (HR 1.8 95%CI 1.1-3.0, p=0.016) were shown to have an association with survival in the favorable profile. In the moderate and unfavorable profiles, only the KPS affected survival (HR 2.3. 95%CI 1.7-3.0, p<0.001) and (HR 1.9, 95%CI 1.5-2.3, p<0.001), respectively.
Training data set and validation data set
Based on the results of the three multivariate analyses, the cohort was divided into eight groups (figure 3A). By comparing the median survival of the groups, four final categories A, B, C and D were created (table 6). Patients in category A had a median overall survival of 31.2 months (95%CI 25.2-37.3) , compared to 15.4 months (95%CI 11.9-18.2) for patients in category B, 4.8 months (95%CI 4.1-5.4) for patients in category C and 1.6 months (95%CI 1.4-1.9) for patients in category D (figure 3B and table 7). Harrell’s c-statistic was 0.71, when calculated based on the training data set.
Patients in category A of the validation data set had a median survival of 16.3 months (95%CI 11.1-21.6), compared to 12.8 months (95%CI 9.5-16.0) for category B, 7.0 months (95%CI 5.1-9.0) for category C and 3.6 months (95%CI 2.6- 4.6) for category D (figure 3C and table 7). The c-statistic based on the validation data set was 0.69.
IV
PREDICTIVE MODEL
Table 6. Groups based on multivariate analysis
Clinical Profile
KPS
VM/BRM
MOS (95%CI)
N (%)
Category
Favorable Favorable Favorable Favorable
Moderate Moderate
100-80 100-80 70-10 70-10
100-80 70-10
No Yes No Yes
N/A N/A
N/A N/A
31.2 (25.2-37.3) 14.0 (6.8-21.1) 18.6 (16.0-21.1) 4.8 (2.3-7.3)
12.5 (6.5-18.5) 4.8 (4.0-5.6)
4.5 (3.1-5.8) 1.6 (1.4-1.9)
116 (12) A 42 (4) B 87 (9) B 52 (5) C
97 (10) B 190 (19) C
132 (13) C 278 (28) D
Unfavorable 100-80 Unfavorable 70-10
KPS: Karnofsky Performance survival.
Status. VM/BRM: visceral and/or brain metastases. MOS: median overall
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