Long-term relapses of breast cancer: questions, interpretations and hypotheses.

The author has demonstrated in previous publications that the consistent characteristic of long-term relapses of carcinoma after more than 8 years from surgery is hormone dependence, since long-term relapses occur almost exclusively in hormone-dependent tumors such as carcinoma of the breast, prostate, endometrium and thyroid. Such publications presented a series of 237 long term relapses of breast cancer that occurred at no less than 8 years from the mastectomy, which proved that all the patients were estrogen-receptor positive. Estrogen-negative cases who did not relapse after 8 years from surgery should be considered cured, as is found for cases of non-hormone-dependent tumors. Therefore, the study demonstrates that breast cancer, without the presence of hormone receptors (which influence clinical behavior) is similar to neoplasms that arise in all parts of the body. The author herein presents a personal hypothesis relative to the possibility that the presence of receptors indirectly conditions the formation of antimitotic factors up to determining in some cases the phenomenon of long-term relapses. Such factors are presumably physiological, and the possibility that such a hypothesis can also serve to explain the results obtained with hormone therapy of breast cancer is examined.