Effects of age and lateralization on lymphoscintigraphic interpretation.

The present study was undertaken to find out if ageing and lateralization might influence the results of lymphoscintigraphic investigations. Axillary lymphoscintigrams obtained in 756 women after subcutaneous intercostal (IC) injection of 99mTc-labelled colloids at the level of the chest wall were reviewed and analysed according to age (<41 years, 41-50 years, 51-60 years, 61-70 years, 71-80 years, >80 years) and the side injected (right or left). No axillary nodes were visualized (IC-) in 34% of the population, and IC- cases were somewhat, but not significantly (0.10<P<0.05) more frequent after injections in the left side (37%) than after injections in the right side (31%). The frequency of IC - cases increased with age (<41 years, 26%; 41-50 years, 29%; 51-60 years, 36%; 61-70 years, 39%; 71-80 years, 40%; >80 years, four out of seven), and the absence of drainage was more common in patients over 50 years old (overall, 38.2%; right, 36%; left, 40.2%) than in younger cases (overall, 27.9%; right, 24.1%; left, 30.3%). From a statistical point of view, the differences between these two age-discriminated populations were significant both when considering the series of injections as a whole (0.01>2P>0.001) and injections in the right side only (0.01<2P<0.02). In conclusion, ageing and lateralization influence lymphoscintigraphic investigations and have to be taken into account when analysing results.