Mondor's disease is a superficial thrombophlebitis of the thoracic wall 
frequently affecting the female breast. In most cases the etiology is unknown, 
although operation, direct and indirect trauma, are known as causative factors. 
This material comprises five women, all with Mondor's disease of the breast. One 
patient did not return for follow-up, in one patient biopsy was performed after 
2 weeks. In the remaining three patients the lesion had disappeared after 9 and 
10 weeks. Mondor's disease has no relationship to cancer or systemic disease, 
and no treatment apart from observation is required.