However, cessation of seizure activity, or AED efficacy, was defined differently by different authors in the selected studies; some were based on termination of seizures alone and others based on a lack of recurrence for a certain period of time.
Based on a 5-year regional recurrence free survival rate of 98%% among controls and 96%% for study subjects, the sample size amounts 439 per arm (including 10%% lost to follow-up), to be able to reject the null hypothesis that the rate for study and control subjects is inferior by at least 5 % with a probability of 0.8.
One possible reason for positive result in recurrence could possibly be due to false positives based on a relatively small number of recurrence cases (less than 10%).
The Genomic Health recurrence score (Onco type Dx® RS) is a prognosticator (breast cancer recurrence) based on a 21 gene expression profile.
Based on a univariate analysis, death following a recurrence and prognosis were related to age of the patients, size of the tumour, tumour location, tumour tissue differentiation, growth pattern, depth of invasion, lymphatic and vascular invasion and lymph node metastasis.
An example of a well conducted, prospectively designed retrospective validation study that used previously collected samples is the colon cancer recurrence score based on a multi-gene real time PCR assay for predicting recurrence in stage II colon cancer [ 14].
The purpose of this study was to analyse the endometrial cancer (EC) patterns of recurrence based on a large French multicentre database according to ESMO-ESGO-ESTRO classification.
Mansueto et al. [ 14] evaluated the economic impact of the introduction of PET/CT in the early detection of suspected ovarian cancer recurrence based on a decision tree model.
Demicheli and colleagues [ 7] have studied the timeline of disease recurrence based on a retrospective database (initiated in the 1940s in Italy) of 1,173 patients treated by the accepted treatments of that era, radical or modified radical mastectomy.
