Inguinal endometriosis is a relatively rare clinical condition, accounting for 1% of extra-uterine locations. Owing to the particular anatomical area affected, the diagnosis in the asymptomatic forms proves difficult. Imaging fails to yield a reliable diagnosis, which is only possible on the basis of histological findings. Rare cases of neoplastic transformation have been reported. The case described here may be emblematic in terms of the migratory pathogenesis of the lesion. Endometriosis is seldom of interest to the general surgeon, since it is generally an exclusively gynaecological condition. Atypical locations, however, do fall within the domain of general surgery, which is what prompted us to review the relevant literature.