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About breast cancer screening

Breast cancer screening

Recently, the number of women with breast cancer has increased in Japan as in other countries, with the prevalence of breast cancers becoming the number one among cancers in women. Currently, it is estimated that about 95,000 women develop breast cancer and about 15,000 of them die for it every year. Its prevalence is so high that one in eleven women is likely to develop breast cancer during their lifetime, but its mortality rate ranks the sixth place among the cancers in women, indicating its relatively good prognosis. Its high survival rate associated with early detection warrants its early detection and treatment. Breast cancer begins to increase at the late 30s, and is characterized by two peaks in the late 40s and early 60s (Fig. 1). Therefore, receiving breast cancer screening is recommended once every two years even for the women without any symptom after the age of 40. Some data indicate that about 15% of breast cancer patients found do not experience any subjective symptoms.
Subjective symptoms of breast cancer include dimple-like breast twitching, breast lumps, nipple discharge, and breast pains. It is advisable to conduct self-examination in front of a mirror to check for these abnormalities. When symptoms are found, you should visit a medical institution even if you are under the age of 40 years old or expecting the next breast cancer screening soon.

In specialized hospitals, mammography and breast ultrasonography are usually performed in addition to visual inspection and palpation. Breast cancer screening is available in obstetrics and gynecology department as well as breast surgery department. When visiting an obstetrics and gynecology department, please refer to a list of doctors certified for screening mammography interpretation and the breast disease certified doctors approved by the Japanese Breast Society for Gynecologists and Obstetricians.

Figure 1. Breast cancer prevalence by age group (2015, national estimate)