'Occult' breast cancer

The aim of this paper is to explore current trends in the diagnosis, invest igation and treatment of patients presenting with axillary lymph node metas tases without a primary in the breast being found and, more rarely, those c ases with metastatic breast cancer where the primary remains unknown - the so-called, 'occult' breast cancer. A retrospective study of 25 reported cas es were selected from our database at the Royal Marsden and 6 patients were found to have true 'occult' breast cancer. These 6 patients are all still alive with no primary ever having been found in the breast. A literature re view was then undertaken exploring the changing trends in this diagnostic e nigma. MRI scanning, it is reported, may reveal the primary. Occult cancers in which imaging totally fails to show the primary will become increasingl y rare. The prognosis of these, however, may be surprisingly better than on e would expect from the nature of their presentation.