The armpit pressure pain to check their own armpit there is no palpable mass, if there is obvious palpable mass to further clarify the nature of the mass, or what disease is causing the armpit mass, there are several reasons: a. sebaceous cysts, the armpit hair is more abundant, sebaceous glands overproduction, poor drainage will lead to pore blockage, further inducing infection. You can localize anti-inflammatory treatment, and consider surgery if the effect is not good. There are physiological and pathological breast enlargement, which may change with menstruation, and pathological ones need to be alert to the possibility of cancer. Breast cancer is a very common tumor for women, and metastasis of axillary lymph nodes may occur in the late stage of breast cancer.