@article{oai:nagasaki-u.repo.nii.ac.jp:00021975,
 author = {Tomita, Masao and Ayabe, Hiroyoshi and Kawahara, Katsunobu and Tagawa, Yutaka and Hara, Shinsuke},
 issue = {1-4},
 journal = {Acta medica Nagasakiensia},
 month = {Dec},
 note = {Fifteen patients with bilateral breast cancer were clinically analyzed on the basis of a result of surgical treatment, in whom eight patients had bilateral synchronous breast cancer, four were non-synchronous and the remaining three were metastatic breast cancer, respectively. The prognosis of patients with bilateral breast cancer was not pessimistic, indicating that it depended on the disease stages of each cancer. On the other hand, it was emphasized that the prognosis of patients with bilateral metastatic breast cancer was extremely poor. Surgeons should be aware of high risk of contralateral breast cancer in careful follow-up following mastectomy for breast cancer. It is generally accepted that patients with cancer of one breast have a higher than average risk of developing cancer of the opposite breast. It is not so rare that bilateral breast tumors are seen in an identical patient on account of the effectiveness of high resolution mammography and sonography in early detection. It is known that a cancer of one breast means the most frequent precancerous lesion of the opposite breast. Bilateral breast cancer may occur in any of the following ways. 1. Bilateral simultaneous breast cancer occurring independently in both breasts and at the same time (syncronous). 2. Bilateral primary non-simultaneous breast cancer occurring independently in each breast but at different times (asynchronous). 3. Bilateral secondary breast cancer occurring either simultaneously or non-simultaneously but as one of the manifestations of metastatic dissemination. However, despite these simple definitions, there is often great difficulty in determining the exact type of bilateral breast cancer under consideration, in particular, identifying second primary cancer from metastatic one. In this study, bilateral breast cancers were clinicopathologically reviewed on the basis of a result of surgical treatment at the First Department of Surgery, Nagasaki University School of Medicine., Acta medica Nagasakiensia. 1991, 36(1-4), p.136-140},
 pages = {136--140},
 title = {Bilateral Breast Cancer},
 volume = {36},
 year = {1991}
}