Chemotherapy Flashcards
What are the different biopsy techniques?
FNA
Tru-Cut: Tumour sampled under LA
Incisional: Tumour sampled at surgery
Excisional: Whole mass removed
What is cytoreductive surgery?
Reduce the bulk of the tumour
Ovarian cancer
Likely to be of benefit if there is effective therapy for residual
Give examples of palliative surgery for cancer
Bypass procedure for bowel obstruction due to intra-abdo tumour
Orthopaedic pinning of pathological fractures
What is the mechanism of action for chemotherapy?
Most target DNA directly or indirectly
Chemotherapeutic agents are toxic towards actively proliferating cells
What are the uses of chemotherapy?
Neoadjuvant Primary Adjuvant Palliative Curative Prophylactic
What is neoadjuvant treatment in chemotherapy?
Pre-op treatment of an operable tumour before surgery with the intent of shrinking the tumour & treating micro metastases
Osteosarcoma
What is adjuvant treatment in chemotherapy?
Following complete macroscopic clearance at surgery. Used to treat occult microscopic mets which usually lead to relapse
What types of cancer are chemo-sensitive?
Breast
Ovarian
Colorectal
When can Tamoxifen be used?
In-situ breast cancer before invasive carcinoma is recognised
Why is chemotherapy given as a combination of different drugs?
- Different classes have different actions, may kill more cancer cells together (synergism)
- Less chance of drug resistant malignant cells emerging
- Drugs with different sites of toxicity are combined dose can be maintained for each drug
What normal cells are most effected by chemo?
Haematopoietic stem cells= myelosuppression
Lining of the GI tract= mucositis
What is a conventional dose defined as?
Dose of drugs known to be effective against the particular malignancy which in the majority causes tolerable side effects.
When are high dose chemo treatments acceptable?
Greater toxicity Required specialised supportive care Justified in long term survival or cure Ewings Sarcoma Hodgkin's disease
In what type of cancer is maintenance chemo used?
Childhood leukaemia used for 18months following complete remission.
Long-term can lead to resistant clones & inc toxicity
What are the regional types of chemotherapy?
Intravesical: Superficial bladder Ca, produces high doses at the tumour site with little systemic absorbance
Intraperitoneal: Administered directly into peritoneal cavity in context of tumours spread trans-coelomically (ovarian)
Intra-arterial: Any tumour with well defined blood supply, higher doses to involved site & reduced systemic toxicity
Which diseases can chemo be used for palliation?
Limited response Renal Melanoma Head & neck Pancreatic Biliary-tract
Which diseases can chemo prolong survival & cure a few in advanced disease?
Non-small cell lung Colorectal Bladder Prostate Breast Gastric
Which diseases can chemo cause remission in most patients?
Curable chemo cancers
Breast
Ovarian
Small cell lung
What are the aims of combined chemo regimens?
Maximise cell kill
Minimize toxicity to non-tumour cells
Minimise development of resistance
What types of drugs can be given in ovarian cancer?
Platinum drugs
Paclitaxel
What is platinum toxic to?
Kidneys (drug is excreted by the kidneys)
Rare: Paralytic ileus due to autonomic neuropathy
Ototoxic
Peripheral neuropathy
What is primary and acquired resistance?
Primary: Initial characteristic of the initial malignant clone
Acquired: Develops through multiple genetic events in tumour progression
What are immediate complications of chemo?
- N&V: Combination of direct stimulation of vomiting centre, peripheral stimulation & anticipatory causes.
- Myelosuppression: Kills haematopoietic progenitor cells. Leads to leucopenia & thrombocytopenia after 10-14days.
- GI upset: Oral mucositis, diarrhoea due to colitis or s.bowel mucosal inflammation. Constipation due to dehydration with reduced oral intake
- Alopecia
- Neurological: Peripheral neuropathies (sensory nerves), autonomic neuropathy, central neurological toxicity, ototoxicity (cochlear damage)
- Nephrotoxicity
- Bladder toxicity
- Extravasation
- Palmar plantar erythema
- Photosensitivity
- Pigmentation (Bleomycin)
How is chemo related N&V treated?
Premed: Ondansetron & dexamethasone
Post-dose: Dexamethasone & Metoclopramide
Anticipatory nausea: Lorazepam
5-HT antagonists- Ondansetron
