Lumps that develop inside woman’s breast and are filled with fluid are considered as breast cysts. They are common for women of all age and sometimes are not so easily detectible, though it may vary in number and sizes. Particular group of women that are especially affected by them are those that are 40-60 years of age. Cysts are considered benign in one of 1,000 cases but some them may be malignant and lead to cancer. Location of the cyst can be anywhere in the breast. The ones that are near the breast surface can be detected by physical exam but for others mammogram or ultrasounds is used.