Metastatic Breast Cancer (Stage V). . Weight gain is a common side effect of chemotherapy, especially in women who go into early menopause .. One study found breast cancer survivors who got chemotherapy were 65 percent more likely to gain weight. Symptoms may last for 1-2 years after treatment or longer.
. chemotherapy, how it is used to treat breast cancer, and what the side effects. of chemotherapy drugs to suppress each stage of the cancer cells' growth.