Metastatic Renal Cell Carcinoma to the Spine and the Extremities

What Is the Value of Undergoing Surgery for Spinal Metastases at Dedicated Cancer Centers?

BACKGROUND

The Alliance of Dedicated Cancer Centers is an organization of 11 leading cancer institutions and affiliated hospitals that are exempt from the Medicare prospective system hospital reimbursement policies. Because of their focus on cancer care and participation in innovative cancer treatment methods and protocols, these hospitals are reimbursed based on their actual billings. The perceived lack of incentive to meet a predetermined target price and reduce costs has spurred criticism of the value of cancer care at these institutions. The rationale of our study was to better understand whether dedicated cancer centers (DCCs) deliver high-value care for patients undergoing surgical treatment of spinal metastases.

QUESTION/PURPOSE

Is there a difference in 90-day complications and reimbursements between patients undergoing surgical treatment (decompression or fusion) for spinal metastases at DCCs and those treated at nonDCC hospitals?

METHODS

The 2005 to 2014 100% Medicare Standard Analytical Files database was queried using ICD-9 procedure and diagnosis codes to identify patients undergoing decompression (03.0, 03.09, and 03.4) and/or fusion (81.0X) for spinal metastases (198.5). The database does not allow us to exclude the possibility that some patients were treated with fusion for stabilization of the spine without decompression, although this is likely an uncommon event. Patients undergoing vertebroplasty or kyphoplasty for metastatic disease were excluded. The Medicare hospital provider identification numbers were used to identify the 11 DCCs. The study cohort was categorized into two groups: DCCs and nonDCCs. Although spinal metastases are known to occur among nonMedicare and younger patients, the payment policies of these DCCs are only applicable to Medicare beneficiaries. Therefore, to keep the study objective relevant to current policy and value-based discussions, we performed the analysis using the Medicare dataset. After applying the inclusion and exclusion criteria, we included 17,776 patients in the study, 6% (1138 of 17,776) of whom underwent surgery at one of the 11 DCCs. Compared with the nonDCC group, DCC group hospitals operated on a younger patient population and on more patients with primary renal cancers. In addition, DCCs were more likely to be high-volume facilities with National Cancer Institute designations and have a voluntary or government ownership model. Patients undergoing surgery for spinal metastases at DCCs were more likely to have spinal decompression with fusion than those at nonDCCs (40% versus 22%; p < 0.001) and had a greater length and extent of fusion (at least four levels of fusion; 34% versus 29%; p = 0.001). Patients at DCCs were also more likely than those at nonDCCs to receive postoperative adjunct treatments such as radiation (16% versus 13.5%; p = 0.008) and chemotherapy (17% versus 9%; p < 0.001), although this difference is small and we do not know if this meets a minimum clinically important difference. To account for differences in patients presenting at both types of facilities, multivariate logistic regression mixed-model analyses were used to compare rates of 90-day complications and 90-day mortality between DCC and nonDCC hospitals. Controls were implemented for baseline clinical characteristics, procedural factors, and hospital-level factors (such as random effects). Generalized linear regression mixed-modeling was used to evaluate differences in total 90-day reimbursements between DCCs and nonDCCs.

RESULTS

After adjusting for differences in baseline demographics, procedural factors, and hospital-level factors, patients undergoing surgery at DCCs had lower odds of experiencing sepsis (6.5% versus 10%; odds ratio 0.54 [95% confidence interval 0.40 to 0.74]; p < 0.001), urinary tract infections (19% versus 28%; OR 0.61 [95% CI 0.50 to 0.74]; p < 0.001), renal complications (9% versus 13%; OR 0.55 [95% CI 0.42 to 0.72]; p < 0.001), emergency department visits (27% versus 31%; OR 0.78 [95% CI 0.64 to 0.93]; p = 0.01), and mortality (39% versus 49%; OR 0.75 [95% CI 0.62 to 0.89]; p = 0.001) within 90 days of the procedure compared with patients treated at nonDCCs. Undergoing surgery at a DCC (90-day reimbursement of USD 54,588 ± USD 42,914) compared with nonDCCs (90-day reimbursement of USD 49,454 ± USD 38,174) was also associated with reduced 90-day risk-adjusted reimbursements (USD -14,802 [standard error 1362] ; p < 0.001).

CONCLUSION

Based on our findings, it appears that DCCs offer high-value care, as evidenced by lower complication rates and reduced reimbursements after surgery for spinal metastases. A better understanding of the processes of care adopted at these institutions is needed so that additional cancer centers may also be able to deliver similar care for patients with metastatic spine disease.

LEVEL OF EVIDENCE

Level III, therapeutic study.