Paul A. Blake

Prognostic significance of novel 18F-FDG PET/CT defined tumour variables in patients with oesophageal cancer

PURPOSE (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) combined with computed tomography (PET/CT) is now established as a routine staging investigation of oesophageal cancer (OC). The aim of the study was to determine the prognostic significance of PET/CT defined tumour variables including maximum standardised uptake value (SUVmax), tumour length (TL), metastatic length of disease (MLoD), metabolic tumour volume (MTV), total lesion glycolysis (TLG) and total local nodal metastasis count (PET/CT LNMC). MATERIALS AND METHODS 103 pre-treatment OC patients (76 adenocarcinoma, 25 squamous cell carcinoma, 1 poorly differentiated and 1 neuroendocrine tumour) were staged using PET/CT. The prognostic value of the measured tumour variables were tested using log-rank analysis of the Kaplan-Meier method and Coxs proportional hazards method. Primary outcome measure was survival from diagnosis. RESULTS Univariate analysis showed all variables to have strong statistical significance in relation to survival. Multivariate analysis demonstrated three variables that were significantly and independently associated with survival; MLoD (HR 1.035, 95% CI 1.008-1.064, p=0.011), TLG (HR 1.002, 95% CI 1.000-1.003, p=0.018) and PET/CT LNMC (HR 0.048-0.633, 95% CI 0.005-2.725, p=0.015). CONCLUSION MLoD, TLG, and PET/CT LNMC are important prognostic indicators in OC. This is the first study to demonstrate an independent statistical association between TLG, MLoD and survival by multivariable analysis, and highlights the value of staging OC patients with PET/CT using functional tumour variables.

Propensity score analysis of oesophageal cancer treatment with surgery or definitive chemoradiotherapy

The role of treatments involving surgery versus definitive chemoradiotherapy (dCRT) for oesophageal cancer remains controversial.

N-staging of oesophageal and junctional carcinoma: is there still a role for EUS in patients staged N0 at PET/CT?

AIM To assess whether separate endoscopic ultrasound (EUS) lymph node (N)-staging is still of prognostic value in those staged node negative (N0) at combined positron-emission tomography/computed tomography (PET/CT) in patients with oesophageal cancer (OC). MATERIALS AND METHODS One hundred and seventeen consecutive patients [median age 67 years; 88 male; 98 cases of adenocarcinoma, 19 cases of squamous cell carcinoma (SCC)] staged as N0 at PET/CT underwent EUS to record tumour (T)- and N-stage. The patients were subsequently separated into two groups: EUS N0 (n = 78) and EUS N+ (n = 39). Survival analysis using Kaplan-Meier and Coxs proportional hazard methods was performed. Primary outcome was overall survival from diagnosis. RESULTS EUS N-stage and EUS N0 versus EUS N+ (p = 0.005 and p = 0.001, respectively) were found to be significantly and independently associated with survival in two models of multivariate analysis, in patients staged N0 at PET/CT. EUS T-stage was significantly associated with survival on univariate analysis. CONCLUSION EUS N-staging still has prognostic value in patients staged N0 at PET/CT. There is a significant difference in survival between EUS N0 and positive nodal EUS status in those staged N0 at PET/CT, suggesting PET/CT is unreliable for local staging. PET/CT and EUS continue to have complimentary roles in OC staging.

Small bowel gastrointestinal tumour: An interesting case of presentation, diagnosis and treatment.

We report the diagnosis and surgical management of the interesting case of a patient with a gastrointestinal stromal tumour (GIST).

PWE-160 Prognostic significance of diagnostic delay in patients diagnosed with upper gastrointestinal tract cancer

Introduction Recent public awareness campaigns for symptoms of cancer aim to improve outcomes by diagnosing cancer at an earlier stage. Whilst it is known that stage of disease at diagnosis predicts survival, the prognostic significance of delays in diagnosis and treatment of upper GI cancer is hitherto unknown. Method A prospective study of 150 consecutive upper GI cancer patients [median age 70 yr, 96 male, 102 oesophageal, 48 gastric cancer] presenting to a UK cancer network was performed. Duration of symptoms prior to patient presentation, and times between referral, investigations, diagnosis, and treatment commencement were recorded. Deprivation scores were obtained from the Welsh Indices of Multiple Deprivation (WIMD). Outcome measures were whether potentially curative therapy was possible at time of decision to treat (DTT), and overall survival. Results Median time from onset of symptoms to DTT was 18 weeks (3–143). There was no significant correlation between length of time from symptom onset to DDT and potentially curable disease (Chi26.809, p = 0.146). There was no significant difference in overall survival according to length of time from onset of symptoms to DDT (Chi24.209, p = 0.378). On multivariable analysis, gender (HR 3.600, 95% CI 1.659–7.811, p = 0.001) and overall deprivation rank (HR 1.001, 95% CI 1.000–1.001, p = 0.012) were significantly and independently associated with length of time from symptom onset to DDT. Conclusion Whilst diagnostic and treatment delays can be lengthy, there is no significant overall effect on rates of potentially curable disease or survival. Disclosure of interest None Declared.

Mo1909 Prognostic Significance of Bioelectrical Impedance Analysis Defined Body Composition in Upper Gastrointestinal Cancer

years diagnosed with colorectal cancer between 1985 and 2004 were included in the study. After preprocessing and joining the raw data across both registries, the population consisted of 135,000 data records, containing 60 usable variables for potential inclusion in the model. After dividing the test set into training and testing sets, we used the information gain ration methodology, as well as a novel oversampling balancing technique that generates synthetic data points to account for the loss of information resulting from death of patients between years 1 and 5 post-diagnosis. We selected 11 predictive attributes, including tumor size and extension, lymph node involvement, regional nodes and primary site involvement, stage, histologic type, and demographic factors including age, gender, and place of residence. Then, experiments were run on 25 data classification schemes consisting of basic classifiers (trees, functions, and logistic regression) and boosting meta-classifiers. Using 10-fold crossvalidation, the validity of each of these classification schemes was tested. Results: Combining basic and meta classifiers chosen from the 25 candidate schemes resulted in highly accurate prediction of survival rates using only 11 of the most predictive patient data features from 60 potential features. Namely, the model achieved 89.5% accurate prediction of the 1-year post-diagnosis survival rates of CRC patients, and 86.2% accurate prediction of the 5-year post-diagnosis CRC survival rates. Conclusion: By combining basic and meta-classifiers and using a novel combined database larger than others in preceding studies, a model was developed using just 11 of 60 potential variables to predict mortality rates of CRC patients 1 and 5 years post-diagnosis, with accuracy of approximately 90% and 86%, respectively. The insights generated by this model could aid diagnosed patients and clinicians greatly in developing cancer treatment and surveillance plans.

Mo1925 Prognostic Significance of CT Muscle Density in Upper GI Cancer

Introduction: Upper gastrointestinal (UGI) surgery is by definition high risk and frequently performed in malnourished patients with a significant incidence of sarcopenia (age-associated loss of skeletal muscle mass and function). Nutritional support is an integral component of enhanced recovery protocols (ERP) to mitigate post-operative risk, and the aim of this study was to investigate the prognostic significance of sarcopenia as defined by CT density of muscle mass in UGI cancer. Methods: One hundred and seven consecutive patients undergoing surgery for UGI cancer [median age 66 yr, 79 m, 55 esophageal (46 ACA, 9 SCC), 52 gastric cancer] were studied prospectively. The axial CT slice at the upper border of the fourth lumbar vertebra was identified and a region of interest was drawn around each psoas muscle. The mean psoas muscle CT density (PMD) was calculated within the region in Hounsfield units (HU) by the Agfa PACS system, and the greater of the two density measurements was used for analysis. The primary outcome measure was survival. Results: Median PMD was 49.25 (range -5.55 to 73.73) HU. Nineteen patients (17.8%) had low PMD ( 40 HU 70.4%, p<0.001). On multivariate analysis only rTNM stage was independently associated with survival (HR 2.157, 95% CI 1.450-3.209, p<0.001). Conclusion: CT defined psoas muscle density (PMD) and by implication sarcopenia, is an important and new prognostic indicator in UGI cancer. Patients identified as such should enter targeted strategic ERP protocols.