Abstract
Background Breast cancer in young women also recurs frequently, and the prognosis is poor in a substantial proportion of this particular patient population. Treatment planning requires consideration of issues such as fertility, early menopause, and hereditary predisposition. To that end, we investigated the characteristics of breast cancer in young women treated at our institution. Material and Methods: Early-onset breast cancer was defined as occurring in women under 35 years of age. Of 2,271 patients who underwent surgery for breast cancer during the period from January 2000 to October 2014, 51 young women （2.24%） were included in this study. The clinicopathological factors and 10-year disease-free and overall survival rates of these patients were compared to breast cancer patients aged 35 years or older. Result: Incidences of 4 or more metastatic lymph nodes, grade III cases, and triple negative cases were significantly more frequent in young patients than in older patients （p = 0.002, 0.025, and 0.0174, respectively）. The 10-year disease-free survival rate was 54.8% in young patients and 87.4% in older patients （p = 0.001）; the 10-year overall survival rates in these patients were 80.2% and 93.2%, respectively （p = 0.03）. Conclusions: The prognosis of breast cancer was poorer in patients under 35 years of age than in those aged 35 years or older. Improving the prognosis requires drug therapy planning with a better understanding of the details of the underlying pathological conditions, including the use of genetic analysis.
