Final answer:
Breast tissue and lymph nodes can be removed in Mastectomy surgery, and in some cases, muscle tissue may also be removed.
Step-by-step explanation:
In a Mastectomy surgery, several things can be removed, depending on the situation and the extent of the cancer. The breast tissue is typically removed, as it is the primary site of the cancer. Lymph nodes in the armpit area may also be removed to determine if the cancer has spread. However, muscle tissue is generally not removed unless the cancer has invaded the chest muscles.