A review of studies examining the relationship between progression ...

focusing on particular treatments 23,24 and others requiring only that treatment should be firstline.9,22,25-27 Some restricted the analysis to trials of a certain size, 13,22,27 trials with “mature” survivaldata, 27 or trials which showed a statistically significant difference between treatment arms. 21The majority of the studies restricted their analysis to a single tumour type although some reportedseparate analyses for more than one tumour type 9,10,21,28 and one paper also reported a single analysisacross multiple types of solid tumour. 21 The majority of papers describe the disease state as eithermetastatic or advanced. Within two studies, trials were included if there was a mixture of locallyadvanced and metastatic disease 23,28 but not all studies were explicit about whether they includedstudies with some patients with locally advanced disease. One study of patients with brain tumours(glioblastoma multiforme) was included despite the fact that the tumour type is described as beingaggressive rather than advanced or metastatic. However, the poor median survival in this patientpopulation (14.6 months) suggests that PFS and OS would be important outcomes in this populationand that the treatment intent is palliative rather than curative.13