Basic principles of cancer chemotherapy

1. Basic
principles of
Chemotherapy
Dr. V. S.Swathi
Assistant Professor

3. For Leukaemia and Lymphomas
• Several phases of chemotherapy is required
• Cure can be achieved with aggressive therapy for a prolonged time
Remission induction
• This is given for killing maximum number of cancer cells
Consolidation/ Intensification/ Post remission
• This is given to eradicate any clinically undetectable disease and lower the tumor
cell burden below 103 at which host immune system can keep cancer cells in
control
Maintainenance
• This is given for maintaining or prolonging the remission

4. For Solids tumors
Adjuvant therapy
• It is given after more definitive therapy like surgery for eliminating remaining
disease or undiagnosable micro metastasis
Neoadjuvant chemotherapy
• It is given before definitive therapy to decrease the tumor burden ( Surgery/
Radiation)
Palliative therapy
• It is given when complete eradication of tumor is not possible or patient refused
aggressive therapy.
• It is given to decrease tumor size, to control tumor cell growth and to reduce
symptoms
Salvage therapy
• It is given for getting remission in case of other therapies are failed

5. Dosing of chemotherapy agents
Dose of chemotherapy drugs is adjusted based on:
• Body weight- Used in case of patient body weight is 10-11kg
• Body surface area- It is widely used
• Area under the curve plot
Dose of chemotherapy agents is adjusted in case of renal and hepatic impairment
patients

6. Combination therapy
• It is given generally to get maximum efficacy
Main reasons for combination therapy:
• Overcoming/ preventing resistance
• To kill resting and dividing cells
• To increase effect
• To rescue normal cells
• Chemotherapy regimens are given at short course in cyclic manner

7. Acronyms are used to designate
chemotherapy agents

8. Route of administration
Chemotherapy agents are given in the following routes
• Intravenous route
• Oral
• Subcutaneous
• Intrathecal
• Intra arterial
• Intra peritoneal
• Intra vesicle
• Continuous IV Infusion
• Hepatic artery infusion
• Mostly IV route is used
• Products like liposomal/ pegylated agents are used to decrease toxicities

9. Response to chemotherapy
Complete response(CR)
• Here all clinical, gross and microscopical changes are disappeared
Partial response(PR)
• Here tumor size reduces to half, and lasts for reasonable period
Response rate (RR)
• It is combination of complete and partial response
RR=CR+PR
Stable Disease (SD)
• It indicates tumor neither grows or nor shrinks significantly (Less than 25% change)
Progressive Disease (PD)
• It indicates no response or increase in tumor size or appearance of new lesions
(More than 25% change)

10. Factors affecting response to
chemotherapy
• Tumor cell heterogenecity- Requires aggressive therapy
• Drug resistance- Tumor size is directly proportional to resistance
• Drug intensity- in case of complications dose intensity should be decreased
• Dose density- In case of getting more effect dose density is decreased
Patient specific factors include:
– Poor functional status
– Impaired organ function
– Co morbid conditions