Objective: This study aims to describe characteristics of malignant diseases of the breast in women of very low age (thus with breast cancer diagnosed before 35th year of age) and compare those characteristics with the phenotype of "average" breast cancer in Czech female population.
Methods: 98 women diagnosed with breast cancer before the age of 35 and treated between 2001 and 2010 in private medical center Medicon Praha s.r.o, were enrolled to this retrospective study. The control group of 100 women was constituted by random choice from patients older than 35 years at the time of diagnosis treated in the same time period.
Results: Size of the tumors at presentation were similar in both study groups. Tumors in younger group exhibited higher proliferative activity, higher grade and lower count of estrogen receptors. On the contrary, in the group of older women was significantly higher percentage of lobular type of cancer and also the proportion of in situ carcinomas. The number of multifocal tumors, positivity of HER-2/neu and progesterone receptors were all without statistically significant difference. In younger women neoadjuvant chemotherapy has been used more frequently. Prognosis of the disease did not differ in both groups.
Conclusion: Tumors diagnosed in women younger than 35 years can be considered more aggressive. However, using adequate treatment makes the prognosis comparable in both age groups.