Predicting survival of de novo metastatic breast cancer in Asian women: systematic review and validation study.
BACKGROUND
In Asia, up to 25% of breast cancer patients present with distant metastases at diagnosis. Given the heterogeneous survival probabilities of de novo metastatic breast cancer, individual outcome prediction is challenging. The aim of the study is to identify existing prognostic models for patients with de novo metastatic breast cancer and validate them in Asia.


METHODS
We performed a systematic review to identify prediction models for metastatic breast cancer. Models were validated in 642 women with de novo metastatic breast cancer registered between 2000 and 2010 in the Singapore Malaysia Hospital Based Breast Cancer Registry. Survival curves for low, intermediate and high-risk groups according to each prognostic score were compared by log-rank test and discrimination of the models was assessed by concordance statistic (C-statistic).


RESULTS
We identified 16 prediction models, seven of which were for patients with brain metastases only. Performance status, estrogen receptor status, metastatic site(s) and disease-free interval were the most common predictors. We were able to validate nine prediction models. The capacity of the models to discriminate between poor and good survivors varied from poor to fair with C-statistics ranging from 0.50 (95% CI, 0.48-0.53) to 0.63 (95% CI, 0.60-0.66).


CONCLUSIONS
The discriminatory performance of existing prediction models for de novo metastatic breast cancer in Asia is modest. Development of an Asian-specific prediction model is needed to improve prognostication and guide decision making.
Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore.
Hui
H
Miao
Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore; Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Mikael
M
Hartman
National Clinical Research Centre, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia; Julius Center for Health Sciences and Primary Care, University Medical Center, Utrecht, the Netherlands.
Nirmala
N
Bhoo-Pathy
Department of Hematology Oncology, National University Cancer Institute, National University Health System, Singapore, Singapore.
Soo-Chin
SC
Lee
Department of Surgery, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
Nur Aishah
NA
Taib
Department of Surgery, Tan Tock Seng Hospital, Singapore, Singapore.
Ern-Yu
EY
Tan
Department of Surgery, Tan Tock Seng Hospital, Singapore, Singapore.
Patrick
P
Chan
Julius Center for Health Sciences and Primary Care, University Medical Center, Utrecht, the Netherlands.
Karel G M
KG
Moons
National Clinical Research Centre, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
Hoong-Seam
HS
Wong
Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.
Jeremy
J
Goh
Ministry of Health Holdings, Singapore, Singapore.
Siti Mastura
SM
Rahim
Department of Surgery, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
Cheng-Har
CH
Yip
Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore; Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands.
Helena M
HM
Verkooijen
D044466:Asian People; D001943:Breast Neoplasms / Q000401:mortality* / Q000473:pathology; D005260:Female; D006801:Humans; D008296:Malaysia; D009362:Neoplasm Metastasis / Q000473:pathology*; D009841:Oligonucleotides; D011379:Prognosis; D012846:Singapore
D009841:Oligonucleotides; C548733:SurKex