Pragmatic staging of oesophageal cancer using decision theory involving selective endoscopic ultrasonography, PET and laparoscopy.

BACKGROUND: Following CT, guidelines for staging oesophageal and gastro-oesophageal junction (GOJ) cancer recommend endoscopic ultrasonography (EUS), PET-CT and laparoscopy for T3-T4 GOJ tumours. These recommendations are based on generic utilities, but it is unclear whether the test risk outweighs the potential benefit for some patients. This study sought to quantify investigation risks, benefits and utilities, in order to develop pragmatic, personalized staging recommendations. METHODS: All patients with a histological diagnosis of oesophageal or GOJ cancer staged between May 2006 and July 2013 comprised a development set; those staged from July 2013 to July 2014 formed the prospective validation set. Probability thresholds of altering management were calculated and predictive factors identified. Algorithms and models (decision tree analysis, logistic regression, artificial neural networks) were validated internally and independently. RESULTS: Some 953 patients were staged following CT, by [(18) F]fluorodeoxyglucose PET-CT (918), EUS (798) and laparoscopy (458). Of these patients, 829 comprised the development set (800 PET-CT, 698 EUS, 397 laparoscopy) and 124 the validation set (118 PET-CT, 100 EUS, 61 laparoscopy). EUS utility in the 71.8 per cent of patients with T2-T4a disease on CT was minimal (0.4 per cent), its risk exceeding benefit. EUS was moderately accurate for pT1 N0 disease. A number of factors predicted metastases on PET-CT and laparoscopy, although none could inform an algorithm. PET-CT altered management in 23.0 per cent, and laparoscopy in 7.1 per cent, including those with T2 and distal oesophageal tumours. CONCLUSION: Although EUS provided additional information on T and N category, its risk outweighed potential benefit in patients with T2-T4a disease on CT. Laparoscopy seemed justified for distal oesophageal tumours of T2 or greater.

High-intensity focused ultrasound ablation of liver tumours: can radiological assessment predict the histological response?

Cancer therapies usually depend on cross-sectional imaging for the assessment of treatment response. This study was designed to evaluate the ability of MRI to predict zones of necrosis following the use of high-intensity focused ultrasound (HIFU) to treat liver metastases. Patients with liver metastases, who had been scheduled for elective surgical resection of their tumours, were recruited to this non-randomized Phase II study. In each case, a proportion of an index liver tumour target was ablated. The response to HIFU was assessed after 12 days using contrast-enhanced MRI and compared directly with histological analysis at the time of surgery. Eight patients were treated, of whom six were subsequently assessed with both MRI and histology. There were no major complications. MRI predicted complete ablation in three cases. In each case, histological analysis confirmed complete ablation. In one case, the region of ablation observed on MRI appeared smaller than predicted at the time of HIFU, but histology revealed complete ablation of the target region. The predominant characteristic of HIFU-ablated tissue was coagulative necrosis but heat fixation was evident in some areas. Heat-fixed cells appeared normal under haematoxylin and eosin staining, indicating that this is unreliable as an indicator of HIFU-induced cell death. This study demonstrates that HIFU is capable of achieving selective ablation of pre-defined regions of liver tumour targets, and that MRI evidence of complete ablation of the target region can be taken to infer histological success.

Post hoc economic analysis of temozolomide versus dacarbazine in the treatment of advanced metastatic melanoma.

PURPOSE: To determine the potential economic implications resulting from oral temozolomide (TEM) compared with intravenous (IV) dacarbazine (DTIC) for metastatic melanoma. PATIENTS AND METHODS: We performed a cost-effectiveness (CE) analysis using hazard ratios (HRs) from the phase III (Schering I95-018) trial comparing TEM 200 mg/m(2)/d orally for 5 days every 28 days with DTIC 250 mg/m(2)/d IV for 5 days every 21 days. Sensitivity analyses assessed a range of TEM's efficacy and costs, direct nonmedical costs, and the DTIC schedule. RESULTS: The trial found an overall survival trend favoring TEM; median survival times of patients treated with DTIC and TEM were 6.4 and 7.7 months, respectively (HR = 1.18; 95% confidence interval [CI], 0.92 to 1.52; intention to treat, P =.20). The mean increase in survival of TEM over DTIC was 1.1 months. The projected average costs per patient were greater with TEM than DTIC ($6,902 v $3,697, respectively). The incremental CE ratio using TEM was $36,990 per life-year or $101 per day of life gained. The CE ratio's 95% CI ranged from -$65,180 (DTIC is more effective) to $18, 670 per year of life gained. The CE ratios decreased 50% if direct nonmedical costs were included and increased 50% if DTIC's efficacy was unchanged if given as a single daily dosage. Sixty percent of simulations found TEM with a CE threshold of less than $50,000 per life-year gained. CONCLUSION: Although the base-case efficacy of TEM compared with DTIC was not statistically significant, its associated incremental CE would be comparable with many interventions. TEM for metastatic melanoma illustrates the tension confronting providers choosing between similar agents that markedly differ in convenience and costs.