Block 9 Cancer and treatment

klau253's version from 2017-06-02 22:31


Human Papilloma virus
Question Answer
Low risk strains causing anogenital warts6,11
High risk strains causing cervical CA16, 18
Viral proteins E6,7 inactivatetumor suppressor genes pRb and p53


Question Answer
Metaplasiafrom one fully differentiated cell to another.(Ex. Bladder/Cervix squamous metaplasia, Barrett's metaplasia)
Dysplasiareversible disordered growth with increased division and incomplete maturation, not neoplastic
Papillomasurface epithelia, benign Ex/ squamous papilloma of skin, benign
Adenomasolid and surface glandular epithelia, benign
Teratoma3 germ cell layers, usually in gonads
Lymphomapresent with tumor masses
Leukaemiaonly circulating cells
Hamartomadisorganised mass of mature specialised cells, benign
Choristomatissue located in an abnormal location, benign
Anaplasiamalignant neoplasm composed of undifferentiated cells


Metastasis Routes
Question Answer
Haematogenoususually venous drainage
Lymphaticregional lymph node
Transcoelomicspread to peritoneum/pleural cavities

Treatment of CA

External beam radiotherapy --> directs radiation at the tumor from outside the body
Question Answer
advantagesskin sparing, treat deeper tumor with greater penetration, beam uniformity


Brachytherapy --> radioactive source in direct contact with tumor (most commonly gynaecological/prostate)
Question Answer
Advshorter treatment time, greater deliverable dose, good for hypoxic and slow proliferators
disadvtumor must be accessible, need a well-demarcated tumor, not suitable for tumors that met to regional lymph nodes


Preo-op radiotx
Question Answer
advunresectable lesions may become resectable, extent of surgical resection diminished
disadvdecreased wound healing, decreased safe dose


Post-op radiotx
Question Answer
Advbetter surgical staging, greater safe dose, easier surgical resection, tissue heals better
Disadvdelay in post-op treatment if healing problems


Acute toxicity of radiotx
Question Answer
Mucosal reactions2nd week of radiotx, mucositis
Skin reactions5th week of radiotx
risk factoraccelerated fractionation


Late toxicity of radiotx
Question Answer
Xerostomiamost common, injury to serous acinar cell, leads to dental decay
soft tissue necrosisleads to mucosal ulceration, can result in osteo-/chondroradionecrosis
fibrosiswoody skin texture
ocularcataracts, optic neuropathy, retinopathy
otologicserous otitis media, sensorineural hearing loss
CNSmyelopathy, transverse myelitis, somnolence syndrome,, brain necrosis

Different types of chemotx

Question Answer
Curative chemotxacute leukaemia, Hodgkin's, Non-Hodgkins, small cell lung, germ cell neoplasm, paediatric sarcoma
Adjuvant chemotxbreast, lung, colorectal, pancreatic
neoadjuvant chemotxbladder, breast, head and neck, oesophageal
Palliative chemotxmost common solid tumor


Chemotx SE
Question Answer
Bone marrowdecrease WBC, RBC and platelet
Hair follicleallopecia
GI mucosastomatitis/mucositis
Nausea and vomitingdue to stimulation of vomiting center and nerves in GI tract
Extravasationleakage of IV drugs into surrounding tissues


Chronic toxicity asso/ with chemotx
Question Answer
Pulmonary fibrosisbleomycin, carmustine (BCNU)
CNS dementingBCNU


Modes of resistance to antiCA drug
Question Answer
Change in sensitivity/decrease binding affinity of target enzymesmethotrexate, vinca alkaloids
increased expression of glycoproteinmethotrexate, alkylating agents
formation of drug-inactivating enzymespurine and pyrimidine antimetabolites
Production of reactive chemicalsalkylators, bleomycin, cisplatin, doxorubicin
Increased nucleic acid repair mechanismalkylating agent and cisplatin
reduced activation of pro-drugspurine & pyrimidine antimetabolites


Multidrug resistance-1 gene (MDR-1)
Question Answer
drugs that reverse MDRverapamil, quinidine, cyclosporine
MDR increases resistance to natural drug productsanthracyclines, vinca alkaloids, epipodophyllotoxins


Mechanism of action of chemotx
Question Answer
Cyclophosphamide, decarbazinealkylating agent
methotrexate, 5-fluorouracilantimetabolites
doxorubicinDNA/RNA synthesis
Paclitaxal, vincristine, vinblastineMT stabiliser
RituximabB cell CD20 Ab
Tamoxifenselective estrogen receptor modulator
Imatinibtyrosine kinase inhibitor for chronic myeloid leukaemia