I understand your concern. Getting a second opinion is OK. Other tests can be done to determine the nature of these solid nodules. A mammogram can give us a clue whether the mass is benign or malignant. However, the mammogram findings are still clues and not definitive in nature. A definitive diagnosis will really come from an invasive biopsy procedure, whether it is core needle biopsy (inserting a large bore needle) or an excision biopsy (removing the entire nodule). Other characteristics of a nodule that can point out o a possible malignancy are irregular borders, gritty borders, and skin dimpling over the nodule. I suggest you discuss these options with your doctor (or new doctor if you're planning a second opinion). Regards and God bless..