ABSTRACT
UNLABELLED: The aim of this prospective study was to evaluate the value of (18)F-FDG PET for the assessment of chemotherapy response in patients with non-small cell lung cancer. Furthermore, part of the objective of this study was to compare 2 methods to quantify changes in glucose metabolism. METHODS: In 51 patients, dynamic (18)F-FDG PET was performed before and at 5-8 wk into treatment. Simplified methods to measure glucose metabolism (standardized uptake value [SUV]) and quantitative measures (metabolic rate of glucose [MR(Glu)]), derived from Patlak analysis, were evaluated. The overall survival and progression-free survival with respect to MR(Glu) and SUV were calculated using Kaplan-Meier estimates. Fractional changes in tumor glucose use were stratified by the median value and also the predefined EORTC (European Organization for Research and Treatment of Cancer) metabolic response criteria, and criteria applying cutoff levels similar to those of RECIST (Response Evaluation Criteria in Solid Tumors) were evaluated. RESULTS: When stratifying at the median value of DeltaMR(Glu) and DeltaSUV, the difference in overall survival (P = 0.017 for DeltaMR(Glu), P = 0.018 for DeltaSUV) and progression-free survival (P = 0.002 for DeltaMR(Glu), P = 0.0009 for DeltaSUV) was highly significant. When applying the predefined criteria for metabolic response, the cutoff levels as also used for size measurement (RECIST) showed significant differences for DeltaSUV between response categories in progression-free survival (P = 0.0003) as well as overall survival (P = 0.027). CONCLUSION: The degree of chemotherapy-induced changes in tumor glucose metabolism as determined by (18)F-FDG PET is highly predictive for patient outcome, stratifying patients into groups with widely differing overall survival and progression-free survival probabilities. The use of (18)F-FDG PET for therapy monitoring seems clinically feasible, because simplified methods to measure tumor glucose use (SUV) are sufficiently reliable and can replace more complex, quantitative measures (MR(Glu)) in this patient population.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/drug therapy , Fluorodeoxyglucose F18 , Image Interpretation, Computer-Assisted/methods , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/drug therapy , Adult , Aged , Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/mortality , Female , Humans , Lung Neoplasms/mortality , Male , Middle Aged , Netherlands/epidemiology , Positron-Emission Tomography/methods , Prognosis , Reproducibility of Results , Sensitivity and Specificity , Survival Analysis , Survival Rate , Treatment OutcomeABSTRACT
CONTEXT: It is generally assumed that pancreatic function recovers completely after mild but not after severe acute pancreatitis. OBJECTIVE: To evaluate both pancreatic function and quality of life in patients who had recovered from acute pancreatitis in a long-term follow-up study. PARTICIPANTS: Thirty-four patients (mean age: 56 years) who had recovered from biliary (n=26) or post ERCP (n=8) acute pancreatitis. The mean time after the event was 4.6 years. MAIN OUTCOME MEASURES: Pancreatic function was evaluated by fecal fat excretion, urinary 4-aminobenzoic acid (PABA) recovery, oral glucose tolerance test and pancreatic polypeptide (PP) secretion. In addition, the quality of life was measured by the gastrointestinal quality of life index (GIQLI). RESULTS: Of the 34 patients, 22 (65%) had mild and 12 (35%) had severe acute pancreatitis. Exocrine insufficiency (fecal fat greater than 7 g/24h and/or urinary PABA recovery less than 50%) was present in 22 (65%) patients: in 10 (83%) after severe and in 12 (55%) after mild acute pancreatitis, respectively (P=0.140). Endocrine insufficiency was present in 12 patients (35%): 7 (32%) mild versus 5 (42%) severe acute pancreatitis; P=0.711. the quality of life was significantly impaired after acute pancreatitis, (P=0.024). No significant relationship was found between the severity of the pancreatitis and impairment of the quality of life (P=0.604). CONCLUSION: In a significant proportion of patients who had recovered from acute pancreatitis, exocrine and endocrine functional impairment was found. This finding is not confined only to patients after severe acute pancreatitis. Routine evaluation of pancreatic function after acute pancreatitis should be considered.
Subject(s)
Islets of Langerhans/physiology , Pancreas, Exocrine/physiology , Pancreatitis/physiopathology , Recovery of Function , 4-Aminobenzoic Acid/urine , Acute Disease , Adolescent , Adult , Aged , Dietary Fats/pharmacokinetics , Feces , Female , Follow-Up Studies , Glucose Tolerance Test , Humans , Male , Middle Aged , Pancreatic Polypeptide/blood , Pancreatitis/diagnosis , Quality of Life , Severity of Illness Index , Treatment Outcome , para-AminobenzoatesABSTRACT
UNLABELLED: The use of dynamic (18)F-FDG PET to determine changes in tumor metabolism requires tumor and plasma time-activity curves. Because arterial sampling is invasive and laborious, our aim was to validate noninvasive image-derived input functions (IDIFs). METHODS: We obtained 136 dynamic (18)F-FDG PET scans of 76 oncologic patients. IDIFs were determined using volumes of interest over the left ventricle, ascending aorta, and abdominal aorta. The tumor metabolic rate of glucose (MRGlu) was determined with the Patlak analysis, using arterial plasma time-activity curves and IDIFs. RESULTS: MRGlu using all 3 IDIFs showed a high correlation with MRGlu based on arterial sampling. Comparability between the measures was also high, with the intraclass correlation coefficient being 0.98 (95% confidence interval, 0.97-0.99) for the ascending aorta IDIF, 0.94 (0.92-0.96) for the left ventricle IDIF, and 0.96 (0.93-0.98) for the abdominal aorta IDIF. CONCLUSION: The use of IDIFs is accurate and simple and represents a clinically viable alternative to arterial blood sampling.
