Application of morphometric analysis to patients with lung cancer metastasis to the spine: a clinical study

Abstract

<jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>Predicting the survival rate for patients with cancer is currently performed using the TNM Classification of Malignant Tumors (TNM). Identifying accurate prognostic markers of survival would allow better treatment stratification between more aggressive treatment strategies or palliation. This is especially relevant for patients with spinal metastases, who all have identical TNM staging and whose surgical decision-making is potentially complex. Analytical morphometrics quantifies patient frailty by measuring lean muscle mass and can predict risk for postoperative morbidity after lumbar spine surgery. This study evaluates whether morphometrics can be predictive of survival in patients with spinal metastases.</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>Utilizing a retrospective registry of patients with spinal metastases who had undergone stereotactic body radiation therapy, the authors identified patients with primary lung cancer. Morphometric measurements were taken of the psoas muscle using CT of the lumbar spine. Additional morphometrics were taken of the L-4 vertebral body. Patients were stratified into tertiles based on psoas muscle area. The primary outcome measure was overall survival, which was measured from the date of the patient's CT scan to date of death.</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>A total of 168 patients were identified, with 54% male and 54% having multiple-level metastases. The median survival for all patients was 185.5 days (95% confidence interval [CI] 146–228 days). Survival was not associated with age, sex, or the number of levels of metastasis. Patients in the smallest tertile for the left psoas area had significantly shorter survival compared with a combination of the other two tertiles: 139 days versus 222 days, respectively, hazard ratio (HR) 1.47, 95% CI 1.06–2.04, p = 0.007. Total psoas tertiles were not predictive of mortality, but patients whose total psoas size was below the median size had significantly shorter survival compared with those greater than the median size: 146 days versus 253.5 days, respectively, HR 1.43, 95% CI 1.05–1.94, p = 0.025. To try to differentiate small body habitus from frailty, the ratio of psoas muscle area to vertebral body area was calculated. Total psoas size became predictive of mortality when normalized to vertebral body ratio, with patients in the lowest tertile having significantly shorter survival (p = 0.017). Left psoas to vertebral body ratio was also predictive of mortality in patients within the lowest tertile (p = 0.021). Right psoas size was not predictive of mortality in any calculations.</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>In patients with lung cancer metastases to the spine, morphometric analysis of psoas muscle and vertebral body size can be used to identify patients who are at risk for shorter survival. This information should be used to select patients who are appropriate candidates for surgery and for the tailoring of oncological treatment regimens.</jats:p></jats:sec>

Sarcopenia, but not frailty, predicts early mortality and adverse events after emergent surgery for metastatic disease of the spine

“…populations, confirms its association with poor clinical outcome [24,25,27,30,42,43]. Previous reports on nononcological spinal surgery populations have shown that morphometric analysis of the psoas could predict complications [44] and mortality [45].…”

“…Our results provide new, clinically relevant information to the existing literature regarding the role of sarcopenia on predicting early postoperative outcomes. Gakhar et al and Zhakaria et al have previously reported decreased survival with lower psoas size in patients with spinal metastasis [23,45]. In contrast to our study, Zakaria et al did not examine patients who underwent surgical intervention, but rather those treated with radiation therapy only.…”

“…Furthermore, this measurement is practical and simultaneously available on the same CT scan slice as the psoas muscle area. This technique has previously been used in the metastatic spine population and has shown good correlation with the conventional NTPA measures (r=0.77; p<0.0001) [23,45].…”

Impact of sarcopenia in borderline resectable and locally advanced pancreatic cancer patients receiving stereotactic body radiation therapy

“…The next best option is to use data from multiple studies using percentile based summative values. The literature currently uses a plethora of cohort-specific values, including using the lowest median, tertile, quartile, quintile, or standard deviation (19)(20)(21)23,24,27,28,(33)(34)(35)(36)(37)(38) in the study cohort. We validated our cohort's cutoff, by performing ROC curve analysis with regards to acute radiotoxicities which correlates to approximately a TPA of 500.…”

Prognostic factors in patients with metastatic spine tumors derived from lung cancer—a novel scoring system for predicting life expectancy

“…Finally, a recent study investigated the size of the psoas muscle as a prognostic factor in lung cancer patients with spinal metastasis [ 26 ].…”