Chemotherapy involves the use of cytotoxic drugs
to kill rapidly dividing cancer cells throughout the body. It is a
systemic treatment, meaning it affects both cancerous and some
normal cells, which can lead to side effects like hair loss, nausea,
and low blood counts. Chemotherapy can be used alone or in
combination with surgery, radiotherapy, or other drugs. Its role
varies by cancer type—it may be given as neoadjuvant (before
surgery or radiation), adjuvant (after local treatment), or palliative
(to control symptoms in advanced cases).