Introduction and importancePoland syndrome is a rare malformative disease. It is characterized by agenesis or hypoplasia of the pectoralis major muscle associated or not with a malformation of the ipsilateral thoracic limb. The authors report the fortuitous discovery of a familial case of Poland syndrome in Togo.Case presentationHe was a 25-year-old young man, with no known pathological history, examined as part of a physical fitness assessment and who presented with thoracic asymmetry. The clinical and radiological explorations made it possible to conclude to a Poland syndrome in its minor form without any other associated malformation. In addition, three other paternal uncles of the patient presented with the same clinical symptomatology. In the absence of a clear indication, the patient received no treatment.Clinical discussionPoland syndrome is a rare congenital malformation. The abnormalities encountered are cutaneous-glandular, osteo-cartilaginous and muscular. The etiopathogenesis of the disease is unknown. The diagnosis is clinical and is based on the demonstration of agenesis of the pectoralis major muscle. The disease does not often lead to functional discomfort; therefore the treatment is not systematic and has only aesthetic value.ConclusionA rare congenital disease, Poland syndrome can occur sporadically or in families. Its treatment depends above all on the psychological repercussion of the disease.