RESUMEN
The aim of the study is to assess the prognostic value of different volume-based calculations of tumor metabolic activity in the initial assessment of patients with high-grade bone sarcomas (BS) and soft tissue sarcomas (STS) using F-18 FDG PET/CT.A single-site, retrospective study from 2002 to 2012 including 92 patients with histologically verified high-grade BS (Nâ=â37) or STS (Nâ=â55). All patients underwent a pretreatment F-18 FDG PET/CT scan. Clinical data were registered. Measurements of the accuracy of metabolic tumor volume with a preset threshold of 40% of the maximum standardized uptake value of primary tumor (MTV40%) and total lesion glycolysis (TLG) as prognostic variables and identification of optimal discriminating cut-off values were performed through ROC curve analysis. Patients were grouped according to the cut-off values. All deaths were considered an event in survival analysis. Kaplan-Meier survival estimates and log-rank test were used to compare the degree of equality of survival distributions. Prognostic variables with related hazard ratios (HR) were assessed using Cox proportional hazards regression analysis.Forty-one of 92 patients died during follow-up (45%; 12 BS and 29 STS). Average survival for included patients was 6.5 years (95% CI 5.8-7.3 years) and probability of 5-year survival was 52%. There was a high-significant accuracy of TLG and MTV40% as prognostic variables when looking on all patients and during subgroup analysis. AUCs were higher for TLG than for MTV40%. TLG above optimal cut-off value was the only variable which was independently prognostic for survival throughout multivariate regression analysis of all included patients (Pâ=â0.01, HR 4.78 [95% CI 1.45-15.87]) and subgroup analysis (BS: Pâ=â0.04, HR 11.11 [95% CI 1.09-111.11]; STS: Pâ<â0.05, HR 3.37 [95% CI 1.02-11.11]). No significant results were demonstrated for MTV40%.Volume-based F-18 FDG PET/CT imaging markers in terms of pretreatment estimation of TLG provide supplemental prognostic information to histologic grading, with significant independent properties for prediction of overall survival in patients with high-grade BS or STS.
Asunto(s)
Neoplasias Óseas/diagnóstico , Neoplasias Óseas/patología , Sarcoma/diagnóstico , Sarcoma/patología , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/mortalidad , Niño , Femenino , Fluorodesoxiglucosa F18 , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Imagen Multimodal , Tomografía de Emisión de Positrones , Pronóstico , Modelos de Riesgos Proporcionales , Radiofármacos , Estudios Retrospectivos , Sarcoma/mortalidad , Neoplasias de los Tejidos Blandos/mortalidad , Tomografía Computarizada por Rayos X , Carga Tumoral , Adulto JovenRESUMEN
To assess the prognostic value of primary tumor metabolic activity in patients with high-grade bone sarcomas (BS) or soft tissue sarcomas (STS) using F-18 FDG PET/CT. A single-site, retrospective study including 92 patients with high-grade BS or STS. Pretreatment F-18 FDG PET/CT scan was performed. Clinical data were registered. Accuracy of maximum standardized uptake value of primary tumor (SUVmax) and tumor-to-background (T/B) uptake ratio as prognostic variables and identification of cut-off values to group patients were determined. Kaplan-Meier survival estimates and log-rank test were used to compare survival distributions. Prognostic variables were assessed using Cox proportional hazards regression analysis. Forty-one of 92 patients died during follow-up (45%). Average survival was 6.5 years (95% CI 5.8-7.3 years) and probability of 5-year survival was 52%. Accuracy of SUVmax and T/B uptake ratio as prognostic variables in all patients and during subgroup analysis of patients with STS was significant. No significant results for AUCs were registered in patients with BS. Surgery was independently prognostic for survival throughout multivariate regression analysis of all patients (Pâ=â0.001, HR 3.84) and subgroup analysis (BS: Pâ=â0.02, HR 11.62; STS: Pâ=â0.005, HR 4.13). SUVmax was significant as prognostic variable in all patients (Pâ=â0.02, HR 3.66) and in patients with STS (Pâ=â0.007, HR 3.75). No significant results were demonstrated for T/B uptake ratio. Estimation of primary tumor metabolic activity with pretherapeutic SUVmax using F-18 FDG PET/CT demonstrates independent properties beyond histologic grading for prediction of survival in patients with high-grade STS, but not with high-grade BS.
Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Sarcoma/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/metabolismo , Neoplasias Óseas/mortalidad , Niño , Dinamarca/epidemiología , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Cintigrafía , Estudios Retrospectivos , Sarcoma/metabolismo , Sarcoma/mortalidad , Neoplasias de los Tejidos Blandos/metabolismo , Neoplasias de los Tejidos Blandos/mortalidad , Adulto JovenRESUMEN
PURPOSE: To evaluate the feasibility of (18)F-FDG PET/CT for initial assessment in high-grade bone sarcomas (BS) and soft tissue sarcomas (STS). METHODS: During the years 2001-2010, 89 patients (30 BS, 59 STS) referred for further evaluation and surgical treatment of a high-grade BS or STS also had a PET/CT scan performed for staging preoperatively (n = 68) or within 1 month of surgery (n = 21). Metastatic lesions suggested on the PET/CT scan were confirmed or rejected by histological evaluation, by additional imaging or by follow-up. In 68 patients (28 BS, 40 STS) the relationship between the maximal standardized uptake value (SUVmax) of the primary tumour and survival was examined. RESULTS: The PET/CT scan suggested the presence of 13 metastatic lesions in BS patients (5 lymph node, 8 distant) and 21 metastatic lesions (6 lymph node, 15 distant) in STS patients. The calculated sensitivity (SE) and specificity (SP) were 95 % and 96 % for detection of distant metastases, and the predictive value (PV) of a positive or a negative test was 87 % and 98 %, respectively. SE and SP were 100 % and 90 % for detection of lymph node metastases, and the PV of a positive or a negative test was 27 % and 100 %, respectively. The 5-year survival was 81 % among patients with SUVmax below the median value (≤ 10), but was 33 % among those with SUVmax >10. CONCLUSION: FDG PET/CT for the initial assessment of patients with high-grade BS or STS was feasible with high SE and SP, but in those with lymph node metastases the PV of a positive test was low. The SUVmax of the primary tumour was a strong prognostic factor for survival.