Sir Peter MacCallum Department of Oncology - Research Publications
Permanent URI for this collection
Search Results
1 - 10 of 10
-
ItemAcute radiation oesophagitis associated with 2-deoxy-2-[18F]fluoro-d-glucose uptake on positron emission tomography/CT during chemo-radiation therapy in patients with non-small-cell lung cancer(WILEY, 2017-10)INTRODUCTION: Acute radiation oesophagitis (ARO) is frequently experienced by patients receiving concurrent chemo-radiation therapy (cCRT) for non-small-cell lung cancer (NSCLC). We investigated ARO symptoms (CTCAE v3.0), radiation dose and oesophageal FDG PET/CT uptake. METHOD: Candidates received cCRT (60 Gy, 2 Gy/fx) and sequential FDG PET/CT (baseline FDG0 , FDGwk2 and FDGwk4 ). Mean and maximum standardized uptake value (SUVmean and SUVmax) and radiation dose (Omean and Omax ) were calculated within the whole oesophagus and seven sub-regions (5-60 Gy). RESULTS: Forty-four patients underwent FDG0 and FDGwk2 , and 41 (93%) received FDGwk4 , resulting in 129 PET/CT scans for analysis. Of 29 (66%) patients with ≥ grade 2 ARO, SUVmax (mean ± SD) increased from FDG0 to FDGwk4 (3.06 ± 0.69 to 3.83 ± 1.27, P = 0.0019) and FDGwk2 to FDGwk4 (3.10 ± 0.75 to 3.83 ± 1.27, P = 0.0046). Radiation dose (mean ± SD) was higher in grade ≥2 patients; Omean (47.5 ± 20 vs 53.9 ± 10.2, P = 0.0061), Omax (13.7 ± 9.6 vs 20.1 ± 10.6, P = 0.0009) and V40 Gy (8.0 ± 8.2 vs 11.9 ± 7.3, P = 0.0185). CONCLUSIONS: FDGwk4 SUVmax and radiation dose were associated with ≥ grade 2 ARO. Compared to subjective assessments, future interim FDG PET/CT acquired for disease response assessment may also be utilized to objectively characterize ARO severity and image-guided oesophageal dose constraints.
-
ItemClassification and evaluation strategies of auto-segmentation approaches for PET: Report of AAPM task group No. 211(WILEY, 2017-06)PURPOSE: The purpose of this educational report is to provide an overview of the present state-of-the-art PET auto-segmentation (PET-AS) algorithms and their respective validation, with an emphasis on providing the user with help in understanding the challenges and pitfalls associated with selecting and implementing a PET-AS algorithm for a particular application. APPROACH: A brief description of the different types of PET-AS algorithms is provided using a classification based on method complexity and type. The advantages and the limitations of the current PET-AS algorithms are highlighted based on current publications and existing comparison studies. A review of the available image datasets and contour evaluation metrics in terms of their applicability for establishing a standardized evaluation of PET-AS algorithms is provided. The performance requirements for the algorithms and their dependence on the application, the radiotracer used and the evaluation criteria are described and discussed. Finally, a procedure for algorithm acceptance and implementation, as well as the complementary role of manual and auto-segmentation are addressed. FINDINGS: A large number of PET-AS algorithms have been developed within the last 20 years. Many of the proposed algorithms are based on either fixed or adaptively selected thresholds. More recently, numerous papers have proposed the use of more advanced image analysis paradigms to perform semi-automated delineation of the PET images. However, the level of algorithm validation is variable and for most published algorithms is either insufficient or inconsistent which prevents recommending a single algorithm. This is compounded by the fact that realistic image configurations with low signal-to-noise ratios (SNR) and heterogeneous tracer distributions have rarely been used. Large variations in the evaluation methods used in the literature point to the need for a standardized evaluation protocol. CONCLUSIONS: Available comparison studies suggest that PET-AS algorithms relying on advanced image analysis paradigms provide generally more accurate segmentation than approaches based on PET activity thresholds, particularly for realistic configurations. However, this may not be the case for simple shape lesions in situations with a narrower range of parameters, where simpler methods may also perform well. Recent algorithms which employ some type of consensus or automatic selection between several PET-AS methods have potential to overcome the limitations of the individual methods when appropriately trained. In either case, accuracy evaluation is required for each different PET scanner and scanning and image reconstruction protocol. For the simpler, less robust approaches, adaptation to scanning conditions, tumor type, and tumor location by optimization of parameters is necessary. The results from the method evaluation stage can be used to estimate the contouring uncertainty. All PET-AS contours should be critically verified by a physician. A standard test, i.e., a benchmark dedicated to evaluating both existing and future PET-AS algorithms needs to be designed, to aid clinicians in evaluating and selecting PET-AS algorithms and to establish performance limits for their acceptance for clinical use. The initial steps toward designing and building such a standard are undertaken by the task group members.
-
ItemTreatment for non-small-cell lung cancer and circulating tumor cells(FUTURE MEDICINE LTD, 2017-12)Surgery is the main curative therapy for patients with localized non-small-cell lung cancer while radiotherapy (RT), alone or with concurrent platinum-based chemotherapy, remains the primary curative modality for locoregionally advanced non-small-cell lung cancer. The risk of distant metastasis is high after curative-intent treatment, largely attributable to the presence of undetected micrometastases, but which could also be related to treatment-related increases in circulating tumor cells (CTCs). CTC mobilization by RT or systemic therapies might either reflect efficient tumor destruction with improved prognosis, or might promote metastasis and thus represent a potential therapeutic target. RT may induce prometastatic biological alterations in CTC at the cellular level, which are detectable by 'liquid biopsies', though their rarity represents a major challenge. Improved methods of isolation and ex vivo propagation will be essential for the future of CTC research.
-
ItemNo Preview AvailableAbsence of a Relationship between Tumor 18F-fluorodeoxyglucose Standardized Uptake Value and Survival in Patients Treated with Definitive Radiotherapy for Non-Small-Cell Lung Cancer(LIPPINCOTT WILLIAMS & WILKINS, 2014-03)INTRODUCTION: A recent meta-analysis suggested that patients with non-small-cell lung cancer (NSCLC) whose primary tumors have a higher standardized uptake value (SUV) derived from F-fluorodeoxyglucose positron emission tomography (PET) have a worse prognosis in comparison with those with tumors with lower values. However, previous analyses have had methodological weaknesses. Furthermore, the prognostic significance over the full range of SUV values in patients treated nonsurgically remains unclear. The aim of this retrospective study was to investigate the relationship between survival and maximum SUV (SUV(max)) analyzed as a continuous variable, in patients with NSCLC, staged using PET/computed tomography (CT) and treated with radiotherapy with or without chemotherapy. METHODS: Eligible patients had a histological diagnosis of NSCLC, were treated with radical radiotherapy with or without chemotherapy as their primary treatment, and had pretreatment PET/CT scans. SUV(max), defined as the maximum pixel SUV value retrieved from the primary tumor, was analyzed primarily as a continuous variable for overall survival. RESULTS: Eighty-eight patients met eligibility criteria: stage I, 19; stage II, 10; and stage III, 59. Median SUV(max) was 15.0 (range, 2.5-56). Higher stage was associated with higher SUV(max) values (p = 0.048). In univariate analysis, there was no evidence of a prognostic effect of SUV(max) (hazard ratio per doubling = 0.83; 95% confidence interval, 0.62-1.11; p = 0.22). Analyzing SUV(max) as a dichotomous variable (median cut point = 15.0), the hazard ratio (high: low) for risk of death was 0.71, with p = 0.18 (95% confidence interval, 0.44-1.15). CONCLUSIONS: In this cohort of patients, increasing SUV(max) derived from F-fluorodeoxyglucose-PET/CT was associated with increasing tumor, node, metastasis (TNM) stage. We found no evidence of an association of increasing SUV(max) with a shorter survival. Previous reports of an association between prognosis and SUV(max) may partly be the result of methodological differences between this study and previous reports and an association between stage and SUV(max).
-
ItemAssociation between radiation pneumonitis and tumor response in patients with NSCLC treated with chemoradiation(BIOMED CENTRAL LTD, 2014-10-16)Dang and colleagues recently reported in the journal that tumor response to definitive chemoradiation, as assessed using the RECIST criteria, and the risk of radiation pneumonitis were positively correlated in patients with non-small cell lung cancer (NSCLC). We had previously reported similar findings in a study that used positron tomography both to measure tumor response and to assess normal tissue toxicity in patients treated with chemoradiation for NSCLC. Taken together these reports suggest that radiosensitivity of normal tissues and tumors may be strongly linked in a proportion of patients with lung cancer.
-
ItemThe utility of 18 F-FDG PET/CT for suspected recurrent breast cancer: impact and prognostic stratification(BMC, 2014-04-22)BACKGROUND: The incremental value of 18FDG PET/CT in patients with breast cancer (BC) compared to conventional imaging (CI) in clinical practice is unclear. The aim of this study was to evaluate the management impact and prognostic value of 18 F-FDG PET/CT in this setting. METHODS: Sixty-three patients who were referred to our institution for suspicion of BC relapse were retrospectively enrolled. All patients had been evaluated with CI and underwent PET/CT. At a median follow-up of 61 months, serial clinical, imaging and pathologic results were obtained to validate diagnostic findings. Overall Survival (OS) was estimated using Kaplan Meier methods and analyzed using the Cox proportional hazards regression models. RESULTS: Forty-two patients had a confirmed relapse with 37 (88%) positive on CI and 40 (95%) positive on PET/CT. When compared with CI, PET/CT had a higher negative predictive value (86% versus 54%) and positive predictive value (95% versus 70%). The management impact of PET/CT was high (change of treatment modality or intent) in 30 patients (48%) and medium (change in radiation treatment volume or dose fractionation) in 6 patients (9%). Thirty-nine patients (62%) died during follow-up. The PET/CT result was a highly significant predictor of OS (Hazard Ratio [95% Confidence Interval] =4.7 [2.0-10.9] for PET positive versus PET negative for a systemic recurrence; p = 0.0003). In a Cox multivariate analysis including other prognosis factors, PET/CT findings predicted survival (p = 0.005). In contrast, restaging by CI was not significant predictor of survival. CONCLUSION: Our study support the value of 18 F-FDG PET/CT in providing incremental information that influence patient management and refine prognostic stratification in the setting of suspected recurrent breast cancer.
-
ItemSpleen Volume Variation in Patients with Locally Advanced Non-Small Cell Lung Cancer Receiving Platinum-Based Chemo-Radiotherapy(PUBLIC LIBRARY SCIENCE, 2015-11-24)There is renewed interest in the immune regulatory role of the spleen in oncology. To date, very few studies have examined macroscopic variations of splenic volume in the setting of cancer, prior to or during therapy, especially in humans. Changes in splenic volume may be associated with changes in splenic function. The purpose of this study was to investigate variations in spleen volume in NSCLC patients during chemo-radiotherapy. Sixty patients with stage I-IIIB NSCLC underwent radiotherapy (60 Gy/30 fractions) for six weeks with concomitant carboplatin/paclitaxel (Ca/P; n = 32) or cisplatin/etoposide (Ci/E; n = 28). A baseline PET/CT scan was performed within 2 weeks prior to treatment and during Weeks 2 and 4 of chemo-radiotherapy. Spleen volume was measured by contouring all CT slices. Significant macroscopic changes in splenic volume occurred early after the commencement of treatment. A significant decrease in spleen volume was observed for 66% of Ca/P and 79% of Ci/E patients between baseline and Week 2. Spleen volume was decreased by 14.2% for Ca/P (p<0.001) and 19.3% for Ci/E (p<0.001) patients. By Week 4, spleen volume was still significantly decreased for Ca/P patients compared to baseline, while for Ci/E patients, spleen volume returned to above baseline levels. This is the first report demonstrating macroscopic changes in the spleen in NSCLC patients undergoing radical chemo-radiotherapy that can be visualized by non-invasive imaging.
-
ItemLung cancer prognostic index: a risk score to predict overall survival after the diagnosis of non-small-cell lung cancer(NATURE PUBLISHING GROUP, 2017-08-22)INTRODUCTION: Non-small-cell lung cancer outcomes are poor but heterogeneous, even within stage groups. To improve prognostic precision we aimed to develop and validate a simple prognostic model using patient and disease variables. METHODS: Prospective registry and study data were analysed using Cox proportional hazards regression to derive a prognostic model (hospital 1, n=695), which was subsequently tested (Harrell's c-statistic for discrimination and Cox-Snell residuals for calibration) in two independent validation cohorts (hospital 2, n=479 and hospital 3, n=284). RESULTS: The derived Lung Cancer Prognostic Index (LCPI) included stage, histology, mutation status, performance status, weight loss, smoking history, respiratory comorbidity, sex, and age. Two-year overall survival rates according to LCPI in the derivation and two validation cohorts, respectively, were 84, 77, and 68% (LCPI 1: score⩽9); 61, 61, and 42% (LCPI 2: score 10-13); 33, 32, and 14% (LCPI 3: score 14-16); 7, 16, and 5% (LCPI 4: score ⩾15). Discrimination (c-statistic) was 0.74 for the derivation cohort, 0.72 and 0.71 for the two validation cohorts. CONCLUSIONS: The LCPI contributes additional prognostic information, which may be used to counsel patients, guide trial eligibility or design, or standardise mortality risk for epidemiological analyses.
-
ItemA prospective observational study of Gallium-68 ventilation and perfusion PET/CT during and after radiotherapy in patients with non-small cell lung cancer(BMC, 2014-10-02)BACKGROUND: Non-small cell lung cancer (NSCLC) accounts for 85% of lung cancers, and is the leading cause of cancer deaths. Radiation therapy (RT), alone or in combination with chemotherapy, is the standard of care for curative intent treatment of patients with locally advanced or inoperable NSCLC. The ability to intensify treatment to achieve a better chance for cure is limited by the risk of injury to the surrounding lung. METHODS/DESIGN: This is a prospective observational study of 60 patients with NSCLC receiving curative intent RT. Independent human ethics board approval was received from the Peter MacCallum Cancer Centre ethics committee. In this research, Galligas and Gallium-68 macroaggregated albumin (MAA) positron emission tomography (PET) imaging will be used to measure ventilation (V) and perfusion (Q) in the lungs. This is combined with computed tomography (CT) and both performed with a four dimensional (4D) technique that tracks respiratory motion. This state-of-the-art scan has superior resolution, accuracy and quantitative ability than previous techniques. The primary objective of this research is to observe changes in ventilation and perfusion secondary to RT as measured by 4D V/Q PET/CT. Additionally, we plan to model personalised RT plans based on an individual's lung capacity. Increasing radiation delivery through areas of poorly functioning lung may enable delivery of larger, more effective doses to tumours without increasing toxicity. By performing a second 4D V/Q PET/CT scan during treatment, we plan to simulate biologically adapted RT depending on the individual's accumulated radiation injury. Tertiary aims of the study are assess the prognostic significance of a novel combination of clinical, imaging and serum biomarkers in predicting for the risk of lung toxicity. These biomarkers include spirometry, (18)F-Fluorodeoxyglucose PET/CT, gamma-H2AX signals in hair and lymphocytes, as well as assessment of blood cytokines. DISCUSSION: By correlating these biomarkers to toxicity outcomes, we aim to identify those patients early who will not tolerate RT intensification during treatment. This research is an essential step leading towards the design of future biologically adapted radiotherapy strategies to mitigate the risk of lung injury during dose escalation for patients with locally advanced lung cancer. TRIALS REGISTRATION: Universal Trial Number (UTN) U1111-1138-4421.
-
ItemA Pattern of Early Radiation-Induced Inflammatory Cytokine Expression Is Associated with Lung Toxicity in Patients with Non-Small Cell Lung Cancer(PUBLIC LIBRARY SCIENCE, 2014-10-07)PURPOSE: Lung inflammation leading to pulmonary toxicity after radiotherapy (RT) can occur in patients with non-small cell lung cancer (NSCLC). We investigated the kinetics of RT induced plasma inflammatory cytokines in these patients in order to identify clinical predictors of toxicity. EXPERIMENTAL DESIGN: In 12 NSCLC patients, RT to 60 Gy (30 fractions over 6 weeks) was delivered; 6 received concurrent chemoradiation (chemoRT) and 6 received RT alone. Blood samples were taken before therapy, at 1 and 24 hours after delivery of the 1st fraction, 4 weeks into RT, and 12 weeks after completion of treatment, for analysis of a panel of 22 plasma cytokines. The severity of respiratory toxicities were recorded using common terminology criteria for adverse events (CTCAE) v4.0. RESULTS: Twelve cytokines were detected in response to RT, of which ten demonstrated significant temporal changes in plasma concentration. For Eotaxin, IL-33, IL-6, MDC, MIP-1α and VEGF, plasma concentrations were dependent upon treatment group (chemoRT vs RT alone, all p-values <0.05), whilst concentrations of MCP-1, IP-10, MCP-3, MIP-1β, TIMP-1 and TNF-α were not. Mean lung radiation dose correlated with a reduction at 1 hour in plasma levels of IP-10 (r2 = 0.858, p<0.01), MCP-1 (r2 = 0.653, p<0.01), MCP-3 (r2 = 0.721, p<0.01), and IL-6 (r2 = 0.531, p = 0.02). Patients who sustained pulmonary toxicity demonstrated significantly different levels of IP-10 and MCP-1 at 1 hour, and Eotaxin, IL-6 and TIMP-1 concentration at 24 hours (all p-values <0.05) when compared to patients without respiratory toxicity. CONCLUSIONS: Inflammatory cytokines were induced in NSCLC patients during and after RT. Early changes in levels of IP-10, MCP-1, Eotaxin, IL-6 and TIMP-1 were associated with higher grade toxicity. Measurement of cytokine concentrations during RT could help predict lung toxicity and lead to new therapeutic strategies.