BACKGROUND Occasionally, anterior chest wall chondrosarcoma presents in an unusual manner. OBJECTIVE We report a case of an anterior chest wall chondrosarcoma which was misdiagnosed as a breast tumour. METHODS The hospital notes of the patient and the literature on the disease were reviewed. RESULTS A 28-year old female Nigerian presented with a progressive enlargement of the right breast. Chest radiograph revealed an opacity in the right hemi-thorax. At surgery, the mass was found to be a chondrosarcoma arising from the anterior chest wall with the breast mass compressed anteriorly. This was confirmed by histopathological examination. She was followed up as outpatient but declined to further treatment. CONCLUSIONS An anterior chest wall tumour of the magnitude described, should always be investigated and evaluated adequately prior to surgery in order to avoid a diagnostic pitfall.