When the breast is pinched and a hard lump is found inside, it can be a normal breast gland with a tender texture and mild tenderness on palpation, especially in patients with mammary gland hyperplasia. Mammary gland hyperplasia can also form hyperplastic nodules and hard lumps, so it can also manifest as a mass in the breast gland. The occurrence of mammary gland hyperplasia is related to changes in hormone levels in the body. Due to excessive hyperplasia and incomplete regeneration of the mammary glands, hyperplastic nodules and even, in some patients, regular painful symptoms may appear. In some patients, this is due to the development of a substantial tumor of the breast. This includes benign as well as malignant tumors of the breast, the main manifestation of which is a hard mass. Malignant tumors will present as painless masses or lumps, while benign tumors usually have a smooth surface with clear borders. In malignant lesions, the edges are irregular and can feel nodular and not easily pushed.