Oncology Flashcards
What stage of melanoma does a patient have if biochemistry suggests elevated LDH?
Stage IV (patient has M1c) with the elevation of LDH alone.
What are 3 prognostics factors of stage III melanoma?
3 prognostic factors of stage III melanoma:
- Number of met LNs
- Size of LNs – micro vs. macro
- Ulcerations – upstages the disease
What are the ABCDE clinical features of melanoma?
Clinical features of melanoma (ABCDE):
A. asymmetry B. border is irregular C. colour: blue, black, brown, pink D. diameter >6mm with change E. evolution/enlargement
Describe the 4 stages of melanoma?
Stages of melanoma:
I Less than 1mm +/- ulceration (upstages)
II More than 1mm +/- ulcerations (upstages)
III LN mets
IV Distal mets / elevated LDH levels (automatically stage IV)
For stages II-IV, what 3 imaging modalities are employed? What is their purpose?
Imaging modalities for stage II-IV melanoma:
- Brain-MRI: for brain mets
- CT-CAP: for distal mets
- PET-scan: for resectable distal mets and monitor effect of biologics
Describe the differences in treatment of Stage I and II melanoma.
Rx of melanoma according to stages:
I – full thickness resection with wide margins (both Dx/Rx)
II – LN resection +/- radiotherapy (if >4cm or 4#) +/- clinical trial
What are the 2 most common chemotherapy options in melanoma? What are the indications? What are the MOA of these drugs?
2 most common chemotherapy option in melanoma:
- Darcarbazine (if NO brain mets) – alkylating agent
- Fotemustine (monoRx if brain mets) – alkylating agent
What are 3 common mutations in melanoma? What types of populations do they occur in?
3 common mutations in melanoma:
- BRAF (45%) - intermittent sun exposure
e. g. doctors - KIT/NRAS (15%) - Acral (unrelated to sun exposure)
e. g. mole - KIT (<5%) - chronic sun exposure / Acral
e. g. surfer
What cancers are BRAF mutations implicated in?
BRAF mutation implicated in:
- Common: Melanoma (sporadic) / Prostate
- CRC with no KRAS mutation
- Others (COT): cholangiocarcinoma, ovary, thyroid
What are the biologics used in RCC (renal cell carcinoma) treatment?
RCC Rx (VMP):
VEGF-A inhibition only = bevacizumab
mTOR inhibition = temsitolimus
VEGF and PDGFR inihibition = sunitinib and sorafenib
What is PD-L1 and how is it implicated in cancers?
PD-L1 is found on many tumours, it bind to PD-1 receptors on T-cells and prevent cytokine release and tumour cell destruction via CD4 + and CD8+ cells.
What is Nivolumab?
Nivolumab is a PD-1 inhibitor that is used in advanced melanoma
What are the AEs of ipulimumab?
AEs of ipulimumab include ‘autoimmune reaction’ of a variety of organs:
Skin – rash Colon – colitis Pituitary – hypopituitarism Thyroid – hyper or hypo CNS – GBS, MG, neuropathy
What is the most common SE of vemurafenib (BRAF inhibitor)?
Rash.
What is the MOA of alkylating agents in chemotherapy?
Alkylating agent insert alkyl group into DNA of tumour cells.
What is the clinical significance of EGFR expression in tumour cells?
High EGFR expression in tumour cells suggests:
- End-stage disease / poor outcome
- Poor response to chemotherapy/hormone therapy
- Likely invasive and metastatic disease
Which 2 types of cancer is EGFR found highly expressed?
NSCLC and prostate cancer (>40%)
What is the semantic difference between prognostic and predictive markers?
Prognostic markers give information about outcome independent of treatment
Predictive markers give information about outcome dependant upon a specific treatment
What are 2 biologic therapies used in advanced melanoma?
Treatment for advanced melanoma:
Ipulimumab (CTLA-4 inhibition)
Nivolumab (PD-1 inhibition)
How does one treat the AEs of ipulimumab? What is a consideration of one of these treatments? Are these AEs reversible?
Ipulimumab AEs are essentially autoimmune reactions that generally respond well to steroids, mycophenolate mofetil and TNF-inhibition.
Upon response to treatment, steroid should be weaned slowly as rebound is possible.
With treatment these autoimmune reactions are reversible.
Which interleukin is implicated in T-cell proliferation after activation?
Upon activation of T-cells IL-2 secretion by T-cells mediates further proliferation.
What are CTLA-4 receptors, what role do they play in the normal immune system?
CTLA-4 receptors are co-inhibitory receptors found on T-cell bind preferentially to B7 on APC instead of CD28 and prevent T-cell activation and proliferation. It plays a role in preventing autoimmunity.
In the treatment of advanced melanoma, describe 3 therapeutical options that target specific genetic mutations.
Targeted treatment of advanced melanoma depending on genetic mutations:
- Vemurafenib – BRAF (V600E mutation) inhibition
- Trametinib – MEK inihibition
- Imatinib – cKIT inhibition
What is the clinical significance of ‘ulcerations’ in a melanoma?
In melanoma the presence of ulcerations ‘upstages’ the prognostic stage i.e. confers worse prognosis.
Describe 2 immunohistochemical tests used in the diagnosis of melanoma.
Immuno-histochemical tests that assist with the diagnosis of melanoma:
- MART/melan-A – specific for melanoma
- S-100 protein – monitor treated melanoma
Are primary melanomas visible? Is it useful to screen for melanomas?
> 90% of primary melanomas are grossly visible, therefore non-invasive screening with skin examinations is useful.
What is beta-2 microglobulin? What is the significance of beta-2 microglobulin in haematological tumours? What is the risk of having elevated levels?
B2-microglobulin is light chain of MHC Class I molecules. Determines burden in haematological tumours (myelomas and lymphomas). Elevated levels may form amyloid.
What are 3 predictive factors in a melanoma?
Predictors of behaviour of melanoma: thickness, bleeding and ulceration.
What are the features of Binet staging of CLL and what is it useful for?
Binet staging predicts untreated survival of CLL:
A = < 2 LNs
B = > 3 LNs
C = Anaemia / Thrombocytopenia
Give 4 SEs of VEGF-A inhibition.
VEGF-A inhibition SEs (HHRR):
Haemorrhage / tumour lysis
HTN – predictive sign of good response, Rx with ACEi
Renal impairment / proteinuria
Reversible posterior leucoencephalopathy (aka PRES)
What is ipulimumab?
Ipulimumab:
- Biologic therapy used in metastatic melanoma
- CTLA-4 inhibition: CTLA4 is a co-inhibitor that normally binds preferentially to B7 preventing CD28 binding, causing inhibition of activation of T-cells and proliferation (mediated by IL-2).
What is the response rate of BRAF inhibition with Vemurafenib in melanoma?
Vemurafenib (BRAF inhibition) – 50-70% response rate in Rx of melanoma
What is Lynch Syndrome?
Lynch syndrome (aka HNPCC) is a familial form of CRC (2-3% of CRCs) that should be considered if a family member with CRC or Lynch-related cancer (ESO: endometrial, SB and ovary) at a young age.
In CRC what is the significance of KRAS and BRAF mutations?
Mr Lynch is KRAS and full of BullShit
Lynch = KRAS BRAF = Sporadic cases
What type of receptors are the following ligands for:
VEGF (vascular endothelial growth factor)
bFGF (basic fibroblast growth factor)
PDGF (platelet derived growth factor)
Tyrosine kinase receptors
What type of biological intervention might a tumour with high EGFR expression be responsive to?
Tyrosine kinase inhibitors
List 3 tyrosine kinase inhibitors and give a common indication for each.
PEC:
Panitumumab: CRC with normal wild-type KRAS gene.
Erlotinib: NSCLC (refractory to platinum based chemotherapy) and advanced pancreatic cancer
Cetuximab: advanced CRC and advanced SCC of head/neck
What is the typical patient that will have EGFR+ adenocarcinoma of the lung?
Young asian female non-smoker with adenocarcinoma of the lung have 90% chance of being EGFR + → treatment will be effective.
What SE is a predictor of good response with the use of tyrosine kinase inhibitors. What is the treatment of the SE?
Rash - higher grade rash suggests higher probability of response rate.
Rx: dose reduction of TKI , cream/steroids, +/- ABx (Keflex)
With NSCLC is an EGFR mutation a good predictive marker or poor predictive marker?
o EGFR mutation improved survival with treatment
o EGFR wild type poor survival with treatment
o EGFR status predicts good response to treatment (therefore good predictive marker)
True/False: CRC with KRAS mutation treated with Cetuximab tend to have a good response.
False.
CRC treated with Cetuximab:
KRAS mutation = poor survival with treatment
KRAS wild type = improved survival with treatment
Give the type of defect in the DNA repair pathway for the following clinical syndromes:
- HNPCC
- BRCA 1/2 breast or ovarian cancer
- Mismatch repair leads to mispaired bases.
2. Homologous recombination repair leads to double strand breaks
With regards to the cell cycle, in what state are most cells in?
Majority of cells arrested in quiescent state G0 state
Which of the following is NOT a checkpoint in the cell cycle:
- G0
- G1/S
- Intra-S
- G2/M
- Spindle
G0
Minimize error checkpoints exist at 4 different points in the cell cycle: G1/S, Intra-S, G2/M and Spindle checkpoint (metaphase to anaphase transition)
In the cell cycle what occurs at G0-G1?
Movement from quiescent state to first gap phase where cell is preparing itself for cell division.
Near end G1 phase passes through key transition point called restriction point where it becomes fully committed to undergoing division.
Summary: gets ready for cell division!
In the cell cycle what occurs at G1-S?
Chromosomes are only replicated ONCE
In the cell cycle what occurs at G2-M
Chromosome segregated and 2 daughter cells created
Where is the DNA damage checkpoint?
G1/S = DNA-damage checkpoint (p53)
What is p53?
Guardian of the genome:
- Multiple triggers for activation.
- Activation leads to cell cycle arrest/apoptosis
- > 50% of cancers have loss of p53 function
What is the MOA of topoisomerases inihibitors in the treatment of tumour? Give examples.
Topisomerases are enzymes that regulate the overwinding or underwinding of DNA. Inhibitors cause breaks in DNA leading to apoptosis.
Examples: Etoposide and Ironotecan