Engaging in sufficient physical activity post diagnosis has been consistently associated with reduced treatment-related side effects, recurrence, all cause and cancer specific mortality, and enhanced HRQOL in breast cancer survivors. Research indicates that adults spend the vast proportion of their sitting and light-intensity physical activity. Objective evaluation such as accelerometer provide detailed data of physical activities performed across the day and the week and can give a clearer understanding of the behavior of cancer survivors (Lynch, 2011). The aim of this study was to evaluate and compare accelerometer-based and self-reported measures of physical activity level (PA) in patients having a breast cancer just after the end of adjuvant treatment without incitation or education program.

For this prospective study 31 Women (mean age=66.1 years) with no metastatic breast cancer were included after the treatment. Measures were released with an Actigraph GT3X accelerometer for seven consecutive days then complete the IPAQ-SF every 3 months after the last session of radiotherapy.

The evolution of level MET is not significantly different between P1-P2, P2-P3 and P1-P3 (P>0.05), the score IPAQ-SF between P1-P2 is statistically different (P=0.0461) and is not significantly different between P2-P3 and P1-P3. The analyses of the concordance both methods (Kappa coefficient) reveal poor to fair agreement between data for P1 (k=0.0142), P2 (k=0.0119) and P3 (k=0.0057) period.

The objective measure demonstrates the low physical activity level and no evolution during 3 months after treatment. This study shows poor agreement between accelerometer and self-reported physical activity data, these results are consistent with previous studies in cancer survivors (Pinto 2013, Johnson-Kozlow 2006). The finding of this study highlight the need to estimate physical activity level with objective method before intervention or incitation in breast cancer population.