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Keywords:

  • spinal metastasis;
  • outcomes assessment;
  • randomized controlled trial;
  • Nationwide Inpatient Sample;
  • validity of results

Abstract

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES

BACKGROUND

The effect of randomized controlled trials (RCT) on clinical practice patterns and patient outcomes is understudied. A 2005 RCT by Patchell et al demonstrated benefit for surgical decompression in patients with spinal metastasis (SpM). We examined trends in spinal surgery for patients with SpM before and after publication of the Patchell RCT.

METHODS

The Nationwide Inpatient Sample (NIS) was used to identify a 20% stratified sample of surgical SpM admissions to nonfederal United States hospitals from 2000 to 2004 and 2006 to 2010, excluding 2005 when the RCT was published. Propensity scores were generated and logistic regression analysis was performed to compare outcomes in pre- and post-RCT time periods.

RESULTS

A total of 7404 surgical admissions were identified. The rate of spine surgery increased post-RCT from an average of 3.8% to 4.9% surgeries per metastatic admission per year (P = .03). Admissions in the post-RCT group were more likely to be non-Caucasian, lower income, Medicaid recipients, and have more medical comorbidities and a greater metastatic burden (P < .001). Logistic regression of the propensity-matched sample showed increased odds post-RCT for expensive hospital stay (2.9; 95% confidence interval [CI] = 2.6-3.4) and some complications, including neurologic (1.7; 95% CI = 1.1-2.8), venous thromboembolism (2.8; 95% CI = 1.9-4.2), and decubitis ulcers (15.4; 95% CI = 6.7-34.5). However, odds for in-hospital mortality decreased (0.6; 95% CI = 0.5-0.8).

CONCLUSIONS

Surgery for SpM increased after publication of a positive RCT. A significantly greater proportion of patients with lower socioeconomic status, more comorbidities, and greater metastatic burden underwent surgery post-RCT. These patients experienced more postoperative complications and higher in-hospital charges but less in-hospital mortality. Cancer 2014;120:901–908. © 2013 American Cancer Society.


INTRODUCTION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES

The effect of randomized controlled trials (RCT) on clinical practice patterns is largely unknown.[1] Few studies address this question in the oncology literature. Registry-based studies of prescription patterns before and after cardiovascular RCTs suggest a mixed effect, with some trials having a significant impact on prescription rates, whereas others do not.[2-4] The impact of RCT results on institutional and geographic practice patterns suggests variability in the diffusion of evidence-based standards.[3, 5] Reports of discrepancies between evidence and practice have prompted national discussion on improving the generalizability of trial results[6] and the adoption of guidelines and evidence into medical practice.[7, 8]

RCT effects on practice patterns remain even less clear within procedural and surgical oncology domains. Rea et al showed a significant increase in laparoscopic colectomy procedures for colon cancer after publication of the Clinical Outcomes of Surgical Therapy (COST) trial in 2004.[9] However, data regarding other surgeries and procedures within oncology are scarce.

The effect of RCT publication on surgical practice for spinal metastasis (SpM) has not been studied. In 2005, a RCT by Patchell et al showed a significant benefit for surgical decompression of SpM when combined with radiation therapy versus radiation therapy alone.[10] Prior to publication of the RCT, the benefit of surgery for patients with SpM was uncertain given limited survival and a palliative treatment intent.[11, 12] Previous studies suggested no benefit for simple laminectomy with or without radiation.[13, 14] Advances in spinal decompression and instrumentation techniques suggested benefit in some nonrandomized studies, but definitive evidence was lacking.[15, 16] Given a definitive RCT by Patchell et al, we examined trends in the surgical treatment of SpM in the 5 years preceding and following its publication.

MATERIALS AND METHODS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES

Data Source

The Nationwide Inpatient Sample (NIS) was used to identify all SpM admissions to nonfederal US hospitals from 2000 to 2004 and from 2006 to 2010. Data for the NIS were obtained from all hospital inpatient stays and discharges from states participating in the Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality (AHRQ). The NIS represents the largest public, inpatient, all-payer database in the United States. NIS provides information on approximately 8 million inpatient stays from approximately 1000 hospitals annually, which approximates a 20% stratified sample of US nonfederal community hospitals. Participating hospitals include short-term, general, specialty, public, and academic medical centers. Data presented in this study represent counts from hospital admissions contained within NIS. The sum of the NIS variable for discharge weight (DISCWT) was used to produce estimates of national annual volume. Weighted national estimates were used in the analysis of trends to avoid sampling bias. Additional information regarding the discharge weighting in NIS is published by HCUP.[17]

Patient Selection

All hospital admissions classified with a principal International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnostic code of secondary malignant neoplasm of the brain, spinal cord, nervous system, or bone (198.3, 198.4, 198.5) and ICD-9-CM procedural code (of any priority) for spinal decompression (03.01, 03.09, 03.4, 03.53) or fusion (81.00-81.08, 81.62, 81.63, 81.64) were included in the analyses. The combination of diagnosis and procedure codes identified a SpM cohort that underwent spine surgery during hospitalization, including any metastatic admissions with a nonsurgical discharge diagnosis. To estimate a surgical rate, the number of surgical admissions was divided by the total number of admissions with principal diagnostic codes 198.3, 198.4, or 198.5. Admissions, representing patients, were categorized as having undergone surgery in the 5-year period before (2000-2004) or after (2006-2010) the publication of the study by Patchell et al (Fig. 1).

image

Figure 1. Diagram shows inclusion process for spine surgery admissions from Nationwide Inpatient Sample database.

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Patient and Hospital Characteristics

All available preoperative factors known to influence postoperative outcomes in patients with SpM were analyzed, including demographics, socioeconomic factors, institution characteristics, and medical comorbidities.[18-20] Race was dichotomized into Caucasian and non-Caucasian. Income was determined using the NIS quartiles for ZIP code–based median household income. Low income was defined using the lowest quartile over the study period. Admission type was dichotomized into elective or nonelective, using the NIS variable for admission type (ATYPE). The NIS variable for admissions source (ASOURCE) was used to identify any missing values for admission type as has been previously described.[21] Hospital bed-size is defined in the NIS by the number of hospital beds relative to each hospital's geographic region, location, and teaching status. Hospital teaching status is assigned in the NIS database on the basis of residency training approval by the Accreditation Council for Graduate Medical Education (ACGME), membership in the Council of Teaching Hospitals (COTH), or a ratio of full-time residents to beds of ≥ 0.25. Additional information regarding hospital strata definitions including geographic assignment can be found at AHRQ's HCUP site.[22]

The presence of medical comorbidities was defined using the Elixhauser method.[23] Premorbid paralysis, other neurological deficits, metastatic disease, lymphoma, and primary tumor were excluded from the comorbidity analysis due to the possible association with spinal metastasis. Elixhauser-based comorbidities with known effects on outcomes in spine surgery patients, based on previously published reports, were included and are listed in Table 1.[18, 20, 24] Primary tumor histology for each SpM admission was categorized as lung (ICD-9-CM 162, V10.11), breast (174, 175, V10.3), prostate (185, V10.46), renal cell cancer (189, V10.52), and other or unspecified. Visceral or nonspinal metastases were identified using the ICD-9-CM series 197.XX and 198.XX and myelopathy using 336.3, 336.8, and 336.9.

Outcomes

Length of hospital stay (LOS) was defined as prolonged if LOS was greater than 75% of the LOS in the sample, which was 14 days. Total hospitalization charges were adjusted to 2010 dollar value and expensive hospital stay was defined as total charges greater than 75% of the total charges in the sample, which was $143,648. Disposition was dichotomized as discharge to home versus any other discharge type including a short-term hospital, other transfers, home health care, against medical advice, and death. Complications were identified using ICD-9-CM codes for neurologic complications (997.00-997.09); pulmonary complications (518.5, 518.81, 518.84, 997.3); acute venous thromboembolism events (VTE) (415.11-415.19, 453.40-2, 453.8, 453.9); cardiac complications (997.1 and 410); urinary and renal complications (584.5-584.9, 997.5); gastrointestinal complications (GI) (008.45, 560.1, 997.49); wound infection (998.30, 998.51, 998.59, 998.6, 998.81, 998.83); urinary tract infection (UTI) (595.0, 595.9, 599.0); meningitis (320, 322.9); sepsis (038); pneumonia (481, 482, 486); and decubitus ulcers (707.00-09).

Statistical Analyses

Admission characteristics and hospital-based outcomes were compared according to a pre- and post-RCT group using Pearson's chi-square tests for categorical variables, analysis of variance for parametric continuous variables, and Kruskal-Wallis for all nonparametric continuous variables. Propensity scores, including all variables in Table 1, were generated to obtain an unbiased measure of the association between time of surgery and adverse outcomes.[25] Propensity scores have been used to reduce biased estimates of treatment effects in observational studies.[26] A 1:1 greedy matching technique[27] was used first to match each pre-RCT patient with a unique post-RCT patient on propensity score. Restrictions were set on the matching criteria to within 0.2× (standard deviation) of the propensity score, to increase accuracy in matching. Covariates were compared between pre- and post-RCT groups in the matched sample. Logistic regression analysis was performed before and after matching to test whether post-RCT was independently associated with adverse outcomes. Analyses were performed using SAS software (version 9.1; SAS Institute Inc., Cary, NC). Statistical significance was set at P ≤ .05 and odds ratios are expressed with 95% confidence intervals (CI).

Table 1. Admission Characteristics for Spinal Metastasis 2000-2004 and 2006-2010 (N = 7404)
CharacteristicSurgery Before RCT 2000-2004 (N = 3307)Surgery After RCT 2006-2010 (N = 4097)P
  1. Bold values indicate statistical significance.

  2. Abbreviations: HTN, hypertension; RCT, randomized controlled trial; SD, standard deviation.

Mean age (y) ± SD60 ±1460 ± 14.05
Female sex41.0%41.0%.95
Caucasian race78.1%74.2%<.001
Low income11.1%21.8%<.001
Expected primary payer
Medicare38.5%37.6%<.001
Medicaid7.8%10.8%
Private48.1%45.1%
Other5.6%6.6%
Elective admission type37.6%34.9%.02
Weekend admission12.9%13.0%.93
Teaching hospital70.0%76.8%<.001
Hospital bed size
Small6.0%7.8%<.001
Medium18.2%15.9%
Large75.8%76.4%
Hospital region
Northeast22.7%21.1%<.001
Midwest21.4%19.6%
South35.9%35.5%
West20.1%23.8%
Elixhauser comorbidities
Cardiopulmonary43.1%54.5%<.001
Cardiopulmonary (without HTN)17.5%20.0%<.01
Hematologic15.7%25.1%<.001
Psychiatric6.7%9.0%<.001
Diabetes10.6%14.5%<.001
Obesity2.1%4.6%<.001
Renal1.1%3.8%<.001
Elixhauser comorbidity score
035.9%23.5%<.001
131.1%27.3%
220.6%23.1%
≥312.4%26.1%
Primary tumor histology
Lung23.1%21.9%.09
Breast13.9%12.4%
Prostate12.7%13.5%
Renal12.0%11.6%
Other/unknown38.3%40.6%
Visceral metastasis37.7%46.5%<.001
Myelopathy34.6%41.4%<.001

RESULTS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES

A total of 170,926 admissions were identified in the NIS database with metastatic disease to the central nervous system or bone, and 7404 of these admissions were identified as having undergone spine surgery for SpM (Fig. 1). Estimated national metastatic admission volume over the entire study period was approximately 843,060 admissions, and roughly 36,650 of these admissions underwent spine surgery.

The rate of spine surgery for SpM increased significantly after publication of the RCT from an average rate of 3.8% to 4.9% surgeries per metastatic admission, per year (P = .03), a 22% increase in the average rate of spine surgery for metastatic disease post-RCT (Fig. 2). Similar trends were observed among teaching hospitals, which showed an increase in average annual surgical rates from 4.8% to 6.2% (P = .02) and hospitals in the western United States, which showed an increase from 4.6% to 6.6% (P = .01). Small hospitals demonstrated a nonsignificant increase in average surgical rates, although they experienced a notable increase in surgical rates in 2009 and 2010. The largest year-on-year increases in surgery rates took place between 2007-2009 (Fig. 2).

image

Figure 2. Graph shows rate of spine surgeries per metastatic admission per year. The y-axis indicates total surgical admissions per year divided by total metastatic admissions per year multiplied by 100%. “Overall” indicates entire study sample, “Small” indicates small hospitals, “Teaching” indicates teaching hospitals, and “West Region” indicates hospitals located in the western United States. Surgical rate represents annual weighted discharge estimates calculated using Nationwide Inpatient Sample discharge weighting variable (DISCWT).

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Admissions in the post-RCT group were slightly younger and more likely to be non-Caucasian, low income, and Medicaid recipients (Table 1). Patients who underwent surgery in the post-RCT period had more medical comorbidities compared to those in the pre-RCT group. The distribution of primary tumor histology remained unchanged. Post-RCT surgical admissions demonstrated a 9% increase in the prevalence of visceral metastasis and a 7% increase in the prevalence of myelopathy. Fewer patients were admitted for surgery on an elective basis in the post-RCT group, and admissions were more likely to undergo surgery in a teaching hospital, small hospital, and hospitals located in the western United States (Table 1).

Outcomes pre- and post-RCT showed a significant increase in the rate of several complications including pulmonary, VTE, urinary/renal, UTI, and decubitus ulcers (Table 2). The overall rate of infectious complications increased by 3% and the number of admissions with 3 or more hospital-related complications increased by 1.5%. Despite the increase in complications, the mortality rate for SpM admissions decreased from 5.1% to 4.0% in the post-RCT period. Total hospitalization charges, corrected to 2010 dollars, increased from a median value of $62,078 pre-RCT to $107,298 post-RCT, with a 22% increase in admissions with total hospital charges in the highest quartile. However, post-RCT admissions showed a slight decrease in overall LOS, from a median of 9 to 8 days.

Table 2. Outcomes After Spinal Surgery 2000-2004 and 2006-2010 (N = 7404)
 Surgery Before RCT 2000-2004 (N = 3307)Surgery After RCT 2006-2010 (N = 4097)P
  1. Bold values indicate statistical significance.

  2. a

    Includes only those complications as defined in the table.

  3. Abbreviations: LOS, length of hospital stay; RCT, randomized controlled trial; SD, standard deviation.

Length of hospital stay (days), mean ± SD11 ± 1011 ± 10.02
Median98 
Prolonged LOS (>14 days)26.4%25.4%.32
Total charges ($), mean ± SD$82,462 ± $75,020$139,376 ± $117,375<.001
Median$62,078$107,298 
Expensive hospital stay (>$143,648)12.3%34.1%<.001
Complications
Neurologic1.1%1.6%.06
Pulmonary3.3%4.6%<.01
Venous thromboembolism1.4%4.6%<.001
Cardiac2.1%1.7%.31
Urinary/renal2.4%4.0%<.001
Gastrointestinal3.5%3.6%.71
Wound2.1%2.0%.85
Urinary tract infection7.1%9.5%<.001
Meningitis0.2%0.2%.94
Sepsis2.1%2.3%.66
Pneumonia4.4%5.3%.07
Decubitus ulcer0.2%3.4%<.001
Cardiopulmonary5.1%6.1%.07
Infectious12.3%15.2%<.001
Number of complicationsa
None78.4%71.0%<.001
115.9%19.3%
24.3%6.6%
≥31.6%3.1%
Discharged to home52.2%53.6%<.01
In-hospital mortality5.1%4.0%.02

Propensity Analysis

Using propensity analysis, we successfully matched 2754 (83.3%) of the pre-RCT patients with 2754 (67.2%) of the post-RCT patients. After matching, only renal comorbidities remained significantly different between pre- and post-RCT groups (Supporting Table).

The relationship between RCT status and each outcome of interest was determined using logistic regression at baseline; and, after matching, by propensity scores (Table 3). In the unmatched analyses, when compared to the pre-RCT group, the post-RCT admissions had 3.7 (95% CI = 3.3-4.1) the odds for an expensive hospital stay. Post-RCT patients also had nearly 20 (8.7-44.4) times the odds for decubitus ulcer compared with pre-RCT patients. Post-RCT patients had significantly higher odds for pulmonary complications, VTE, urinary/renal complications, UTI, infectious complications, and any complications overall. In the propensity-matched sample, the odds of post-RCT patients for expensive hospital stay remained high, although the odds for prolonged LOS and for in-hospital mortality decreased. Post-RCT patients also continued to have higher odds for any reported complication (odds ratio = 1.3; 95% CI = 1.1-1.4) including neurologic, VTE, and decubitus ulcers (Table 3). No change was observed in the odds of a patient being discharged to home in the post-RCT period.

Table 3. Comparing Surgery Pre- and Post-RCT Publication for Adverse Outcomes Using Logistic Regression Before and After Stratification on Propensity Score
 Logistic Regression Post-RCT Cohort OR (95% CI)Propensity-Matched Post-RCT Cohorta OR (95% CI)
  1. Abbreviations: CI, confidence interval; LOS, length of hospital stay; OR, odds ratio; RCT, randomized controlled trial.

  2. a

    Propensity score includes all covariates present in Table 1.

  3. b

    Defined as ≥1 complication during hospitalization.

Prolonged LOS (>14 days)0.9 (0.9-1.1)0.7 (0.7-0.8)
Expensive hospital stay (>$143,648)3.7 (3.3-4.1)2.9 (2.6-3.4)
Complications
Neurologic1.5 (1.0-2.2)1.7 (1.1-2.8)
Pulmonary1.4 (1.1-1.8)1.3 (1.0-1.7)
Venous thromboembolism3.5 (2.5-4.9)2.8 (1.9-4.2)
Cardiac0.8 (0.6-1.2)0.7 (0.5-1.1)
Urinary/renal1.7 (1.3-2.2)1.4 (1.0-2.0)
Gastrointestinal1.0 (0.8-1.3)0.9 (0.7-1.2)
Wound1.0 (0.7-1.3)0.9 (0.6-1.4)
Urinary tract infection1.4 (1.2-1.6)1.2 (1.0-1.4)
Meningitis1.0 (0.4-2.8)1.0 (0.3-4.0)
Sepsis1.1 (0.8-1.5)1.0 (0.7-1.5)
Pneumonia1.2 (1.0-1.5)1.1 (0.8-1.4)
Decubitus ulcer19.6 (8.7-44.4)15.4 (6.7-34.5)
Cardiopulmonary1.2 (1.0-1.5)1.1 (0.8-1.3)
Infectious1.3 (1.1-1.5)1.1 (0.3-1.3)
Any complicationb1.5 (1.3-1.6)1.3 (1.1-1.4)
Discharged to home1.2 (1.0-1.3)1.0 (0.9-1.1)
In-hospital mortality0.8 (0.6-1.0)0.6 (0.5-0.8)

DISCUSSION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES

Our findings suggest that publication of a RCT, which demonstrated efficacy in select patients with SpM, resulted in the adoption of the trial results into clinical practice. The rate of surgery increased significantly after publication of the RCT across the study population, particularly among teaching hospitals and hospitals located in the western United States.

Surgical rates showed the largest annual gains approximately 2 to 4 years after publication of the RCT, suggesting a “diffusion” period where RCT results gained wider acceptance and implementation into clinical practice, in a variety of settings (Fig. 2). A similar process of diffusion was also reflected in the literature, because the number of citations per year of the Patchell et al RCT showed a steady increase over time (Fig. 3). This diffusion period appears consistent with some reports of surgical adoption post-RCT,[9, 28] but appears to differ considerably from the decade or more adoption times reported in studies of medication prescription practices after RCT.[4, 7]

image

Figure 3. Histogram shows randomized controlled trial (RCT) citation counts per year, representing the total number of articles that cite the RCT by Patchell et al per year using the “Published Items in Each Year” citation report in Web of Science. (Source: Thomson Reuters Web of Science “Times Cited” Search. Topic: Direct decompressive surgical resection in the treatment of spinal cord compression caused by metastatic cancer: a randomised trial AND Author: Patchell. Accessed September 5, 2013 at: http://thomsonreuters.com/web-of-science.)

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Significant differences existed between patients with SpM who underwent surgery before and after publication of the RCT. Post-RCT admissions were more likely to be low income, Medicaid or self-pay status, and admitted on an emergent or urgent basis. Post-RCT patients also carried more preoperative surgical risk factors with more medical comorbidities and comorbidities specifically associated with suboptimal outcomes after surgery. These admissions had a greater burden of metastatic disease and higher rates of preoperative myelopathy. Our findings suggest a broadening of criteria for surgery and more aggressive care for patients with more advanced metastatic disease, which may lead to a higher risk for poor outcomes.

Propensity-matched, logistic regression analysis suggested several outcomes independently associated with surgery for SpM in the post-RCT period. Patients showed higher odds for postoperative complications including neurologic, VTE, and decubitus ulcer complications. These findings are noteworthy when considering the 4-step, ambulation-based, primary endpoint of the RCT.[10] Our results suggest that surgical patients are suffering from ambulation-related complications in the postoperative in-hospital period, despite the potential long-term gains in ambulatory status suggested by the RCT. Our findings should be considered in the context of post-RCT studies of surgery for SpM, which suggest a loss of functional and ambulatory benefit as age and comorbidities increase.[20, 29]

Post-RCT complications occurred in the setting of significantly reduced odds for in-hospital mortality. Our findings are consistent with mortality results from the Patchell et al RCT (6%).[10] However, no studies, to our knowledge, have described the extent of postoperative complications, total charges, and the discharge dispositions of patients in this population after publication of RCT results. Liberalizing surgical criteria for patients with SpM may increase survival at the risk of higher complication rates.

Our results also suggest how results from an RCT are extrapolated into clinical practice. In the RCT by Patchell et al, patients were excluded if they were not of “acceptable medical status” and had a prognosis less than 3 months.[10] However, the RCT, as published, provided little information regarding socioeconomic status, metastatic burden, and extent of preoperative medical comorbidities. Although this limits our ability to compare the RCT population to our pre- and post-RCT populations, our results suggest a possible widening of patient selection beyond that identified in the RCT to a sicker population that may not experience the same benefit as the RCT population. This finding is important because patients different from the study population may not tolerate surgical treatment as well or have different susceptibility to treatment toxicity.[30] Although concerns over the external validity of RCT results is not new, few measures exist to evaluate external validity, which leaves many clinicians with little guidance in applying trial results to patient care.[1] This highlights the importance of post-RCT studies to assess treatment effects in different populations and to consider later systematic assessment of external validity,[31] as we have done.

Limitations

This study has limitations. The NIS database is the largest all-payer inpatient database in the United States and provides hospitalization and socioeconomic information with known affects on outcomes in patients with SpM.[18, 19] As with any coding-based registry, the reported increase in medical comorbidities and complications in the post-RCT period may have been related to protean coding practices. The time frame selected for this study is large compared to other similar observational studies. However, long-term trends in post-RCT surgical rates and surgical patient characteristics were not taken into account. The 5-year post-RCT period may over- or underestimate the effect of an RCT, particularly under conditions of a Gartner hype cycle in which innovation triggers inflated expectations followed by a period of disillusionment and eventual plateau.[32] Clinical information that may be pertinent for surgical decision-making in patients with SpM, such as imaging results, a detailed neurologic examination, and precise functional status measures, are lacking. However, NIS data such as visceral metastasis and myelopathy provide some insight into preoperative clinical characteristics. Nonetheless, associations in preoperative characteristics pre- and post-RCT do not demonstrate causality. Surgical decision-making for SpM patients is a complex dynamic between patients and clinicians, and no single factor can account for such decisions. Outcomes in this study are also limited to the in-hospital time period and do not reflect long-term outcomes, such as extent and duration of functional recovery, survival, or quality of life. Future studies may elucidate how post-RCT trends translate into posthospitalization survival, patient-centered outcome measures, and the use of adjunct treatment modalities such as radiation therapy. Nonetheless, this study represents the largest and most comprehensive analysis of how, in a substantive proportion of the US population, publication of a RCT may have altered the care and management of patients with metastatic cancer to the spine.

Conclusions

Surgery for patients with SpM is typically palliative and survival often limited. Whether the potential post-RCT broadening of surgical criteria is beneficial for all SpM patients remains difficult to ascertain. Our findings suggest a possible change in the risk:benefit ratio as the population undergoing surgery evolves due to changes in practice patterns and patient selection criteria. The adoption of evidence, and potential ways in which results are disseminated and alter practice, is not well described in the oncology literature and has important implications both for caregivers and for patients.

Concerns over the translation of evidence into clinical practice should focus not only on adoption of evidence into practice, but also how such evidence is interpreted and what effect this has on patient outcomes, which are dynamic processes. Our analysis of changes in spine surgery for metastasis, before and after publication of an RCT, demonstrates challenges and opportunities for understanding both the design and later dissemination of RCTs in oncology.

FUNDING SOURCES

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES

Dr. Weil was supported in part by the Melvin Burkhardt chair in neurosurgical oncology, and by the Karen Colina Wilson research endowment within the Brain Tumor and Neuro-oncology Center at the Cleveland Clinic. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

REFERENCES

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. MATERIALS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. FUNDING SOURCES
  8. CONFLICT OF INTEREST DISCLOSURES
  9. REFERENCES