RESUMO
PURPOSE: Traditional methods of evaluating cardiotoxicity focus on radiation doses to the heart. Functional imaging has the potential to provide improved prediction for cardiotoxicity for patients with lung cancer. Fluorine-18 (18F) fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) imaging is routinely obtained in a standard cancer staging workup. This work aimed to develop a radiomics model predicting clinical cardiac assessment using 18F-FDG PET/CT scans before thoracic radiation therapy. METHODS: Pretreatment 18F-FDG PET/CT scans from three study populations (N = 100, N = 39, N = 70) were used, comprising two single-institutional protocols and one publicly available data set. A clinician (V.J.) classified the PET/CT scans per clinical cardiac guidelines as no uptake, diffuse uptake, or focal uptake. The heart was delineated, and 210 novel functional radiomics features were selected to classify cardiac FDG uptake patterns. Training data were divided into training (80%)/validation (20%) sets. Feature reduction was performed using the Wilcoxon test, hierarchical clustering, and recursive feature elimination. Ten-fold cross-validation was carried out for training, and the accuracy of the models to predict clinical cardiac assessment was reported. RESULTS: From 202 of 209 scans, cardiac FDG uptake was scored as no uptake (39.6%), diffuse uptake (25.3%), and focal uptake (35.1%), respectively. Sixty-two independent radiomics features were reduced to nine clinically pertinent features. The best model showed 93% predictive accuracy in the training data set and 80% and 92% predictive accuracy in two external validation data sets. CONCLUSION: This work used an extensive patient data set to develop a functional cardiac radiomic model from standard-of-care 18F-FDG PET/CT scans, showing good predictive accuracy. The radiomics model has the potential to provide an automated method to predict existing cardiac conditions and provide an early functional biomarker to identify patients at risk of developing cardiac complications after radiotherapy.
Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Radiômica , Cardiotoxicidade , Tomografia por Emissão de PósitronsRESUMO
INTRODUCTION: The goal of the present study was to investigate the predictive and prognostic values of interim fluorine-18 (18F) fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) parameters for the prediction of a complete pathologic response (pCR) in patients with locally advanced rectal cancer (LARC) who had received preoperative chemoradiotherapy (PCRT). PATIENTS AND METHODS: A total 103 patients with LARC were included in the present study. All the patients were evaluated by 18F FDG PET/CT before and after 45 Gy of radiotherapy with concurrent oral capecitabine chemotherapy. The quantitative, volumetric parameters and their percentage of change (Δ%) were used to predict the pCR and calculate the overall survival (OS). The predictive value for a pCR of 18F FDG PET/CT cutoff values were determined by receiver operating characteristic analysis. The prognostic significance was assessed using Kaplan-Meier analysis. RESULTS: A pCR occurred in 22 patients (21.4%). Univariate and multivariate analyses demonstrated that the post-PCRT maximum standardized uptake value (SUVmax2) and change in the SUVmax (ΔSUVmax) as significant factors for the prediction of pCR, with a sensitivity of 68.2% and specificity of 87.7% and sensitivity of 90.9% and specificity of 80.3%, respectively. Kaplan-Meier analysis showed that a low SUVmax2 (< 2.5) and high ΔSUVmax (≥ 62.2%) were potent predictors for OS. CONCLUSION: The present study has shown the capability of interim 18F FDG PET/CT parameters to predict the achievement of pCR after PCRT in patients with LARC. Of the parameters, SUVmax2 and ΔSUVmax were potent predictors for pCR and well associated with OS.
Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/tratamento farmacológico , Quimiorradioterapia Adjuvante/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/tratamento farmacológico , Adenocarcinoma/mortalidade , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Fluordesoxiglucose F18 , Humanos , Interpretação de Imagem Assistida por Computador , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Curva ROC , Radioisótopos , Neoplasias Retais/mortalidade , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
A 35-year-old man presented to the emergency department with a worsening cough and a history of unintended weight loss. Chest radiograph revealed a giant mass occupying the left hemithorax. On CT scan, the mass measured over 20 cm and shifted the heart into the right hemithorax. Bone scan demonstrated multifocal radiotracer uptake within coarse intratumoral calcifications. Biopsy revealed no malignant cells. However, malignancy was clinically suspected due to size, and FDG PET/CT was performed. Mild FDG uptake was present in the mass. The mass was excised, and pathologic examination revealed the rare diagnosis of a giant pulmonary chondroid hamartoma.