# Development and validation of the Home time and Overall survival after Metastatic spine tumor surgery Estimator (HOME score)

## TL;DR

The HOME score is a new tool that predicts how long patients with spine tumors will stay in the hospital and their survival after surgery.

## Contribution

The HOME score is a novel predictive model for post-surgery home time and survival in metastatic spine tumor patients.

## Key findings

- The HOME score includes 17 items for home time prediction and 24 for survival prediction.
- The model's performance was stable across training and testing datasets with AUC and C-index values above 0.70.
- Primary cancer origin and history of CHF were the most influential factors in predictions.

## Abstract

This study reports the development and validation of the Home time and Overall survival after Metastatic spine tumor surgery Estimator (HOME score).

A population cohort study was conducted, including 2348 adults with spine metastases treated with surgery in the 2005 to 2020 Ontario Cancer registry. HOME score predictions were the likelihood of post-surgery home time of 3-months or less, and overall survival at 6 months, 1 year, and 1.5 years after surgery. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) for home time predictions, and the concordance index (C-index) for survival. Variable importance was quantified using standardized coefficients.

Mean age was 62.4 years (SD: 12.6) and the most common primary cancer was lung (N = 513, 21.9%). Patients treated between 2005 and 2018 were allocated to training, and those treated in 2019-2020 were used as a hold-out test cohort. The final model included 17 items for home time prediction, and 24 items for survival prediction including demographic, comorbid, cancer, and presentation features. Performance of the home time model (AUC: 0.70), and survival model (C-index 0.70, 6-month AUC: 0.73, 1-year AUC: 0.75, 1.5-year AUC: 0.76) was stable across training and testing. Primary cancer origin and history of congestive heart failure (CHF) ranked highest among features impacting outcome predictions.

The HOME score (https://shakilh.shinyapps.io/home_app/) accurately predicts home time and survival for patients with spinal metastases undergoing surgery. Key factors influencing predictions were primary origin, and history of CHF. This represents a significant advancement to patient centered preoperative risk stratification.