The feeling of pins and needles in the breasts can be caused by mastitis, breast cancer, breast enlargement and so on. 1. Mastitis: A pins and needles sensation in the breasts may be caused by mastitis, which is usually caused by long-term milk stagnation or bacterial infection. When the patient’s breast is infected, it will cause a local inflammatory reaction, so the pain like pins and needles sensation may occur. 2. Breast Cancer: A pins and needles sensation in the breast may be caused by breast cancer, because the tumor in the breast will infiltrate and compress the surrounding blood vessels, tissues and nerves, which will lead to tingling in the breast. 3. Breast hyperplasia: Breast hyperplasia is usually caused by improper diet, bad mood, hormone level disorders, etc. When breast hyperplasia occurs, the local tissues will stimulate the mammary nerves, which may lead to breast discomfort and tingling in the breasts. At the same time, breast duct dilatation, skin disease around the breast may, tingling around the left breast may also need to consider the possibility of coronary heart disease. There may be other reasons for the pins and needles sensation in the breasts, so you should go to the hospital to find out the cause of the pins and needles pain, and treat it accordingly.