Oncology Flashcards
If you have a constitutional mutation when did this error occur?
At conception, at the zygote stage. Can be inherited or denovo
What does an oncogene do? What does a proto-oncogene do?
Aids in growth and division of healthy cells.
Causes the oncogene to be constantly on leading to growth mutations.
What do germline mutations in the APC gene predispose to?
Hepatoblastoma
In children with transient myeloprolioferative disorder, what cancer are they predisposed to and what percentage of children get it?
25% of these children will get AMKL or MLD
What surveillance is required for children with Beckwith Wiedemanns syndrome?
Exam and 3 monthly abdominal ultrasound until the age of 7
Gene associated with Ewings sarcoma
t(11,22) - EWSR1
Gene mutation in neuroblastoma
MYCN Amplification - High risk with poor prognosis
What causes Li Fraumeni Syndrome?
Defective TP53 in germline = loss of TSG
What is the pathognomonic gene translocation in Alveolar rhabomyosarcoma?
t (1, 13) or t (2, 13)
What present with small round blue cells on biopsy?
Ewings, Neuroblastoma, Rhabdomyosarcoma, Medulloblastoma, wilms, Retinoblastoma, anapaestic hepatoblastic
Which chemotherapy agent can lead to heart failure due to cardiomyopathy?
Doxorubicin
Which chemotherapy agents have the highest risk of secondary malignancy?
Etoposide, cyclophosphamide
Where does a wilms tumour metastasise to most commonly?
Lung
Which renal tumour most commonly metastasises to the brain?
Rhabdoid
Which renal tumour most commonly metastasises to the skeleton?
Clear cell sarcoma
What is the survival for children with a wilms tumour?
90%
Which organ system could be at risk of tumour formation in a child with aniridia?
Renal tumour
WAGR - Wilms
Aniridia
Genitourinary abnormality
Retardation
Which chemotherapy agent can cause pulmonary fibrosis?
Bleomycin
What is the difference between Ewings and Osteosarcoma?
Osteosarcoma: Metaphysis - often knee and proximal humerus, sunburst sclerotic on X-ray, spread to lung and bones, present with pain after exercise, not treated with radiation
Ewings: Diaphysis, pelvic bone tumours, ludic onion skin change on Xray, spread to lungs/bone/marrow, classic translocation t (11, 22), treated with radiation
Which two sarcomas can spread to the bone marrow?
Ewings
Alveolar Rhabdomyosarcoma
Which tumour is associated with opsoclonus/myoclonus, racoon eyes, horners syndrome? What screening test can you do?
Neuroblastoma
Urine catecholamines and MIBG but if suspecting should go on to confirm with body MRI
What does the ch14.18 monoclonal antibody used to treat neuroblastoma target?
GD2 - its an antibody that binds to neuroblastoma cells and induces immune system to attack the cancer via antibody-dependent cell mediated cytotoxicity. Severe pain requiring morphine infusion is frequent. It can cause capillary leakage, fluid retention and allergy.
What can be given to protect against cisplatin induced sensorineural hearing impairment?
Sodium thiosulfate (STS), used in children with hepatoblastoma.
What are the side effects of radiation?
Growth restriction
Hypothyroidism
Early onset coronary artery disease
Pericardial disease
Pulmonary fibrosis
Increased risk of breast cancer
Child presents with nausea, vomiting, abdominal mass and pain in the ileocecal junction area with fever. CT scan shows a mass at the ileocecal junction. What is the most likely diagnosis?
Burkitts lymphoma -90% originate from mature B cells in peyers patches within the GI Tract.
What cell line do Non Hodgkins lymphomas presenting as mediastinal masses originate form?
Thymic T cells
10 year old male, bony non painful mass on his distal femur. Xray - stalks or broad based projections from the surface of the bone with an associated cap that is 0.5cm thick. What is the most likely diagnosis?
Osteochondroma
Metaphyseal lucency of the proximal femur on X-ray that causes pain somewhat relieved by ibuprofen?
Osteoid osteoma
What disease is associated with haemangioblastomas in the cerebellum, medullar and spinal cord?
von Hippel-Lindau disease
Most common malignant CNS tumour in childhood
Medulloblastoma - ~20% cases of CNS tumours. Arise from the posterior fossa (cerebellum). Peak age 3-9 years. Highly malignant primitive neuroectodermal tumour.
Small blue round cells on histopathology.
Most common posterior fossa CNS tumour of childhood?
Cerebellar astrocytoma - present with unsteadiness, clumsiness of the arms and legs, headaches and vomiting
Most common benign CNS tumour in childhood?
Gliomas
Which molecular subgroup of medulloblastoma has the best prognosis and what is the gene mutation?
Group One
WNT gene
>92% survival 5 years
After resection of medulloblastoma that was causing obstruction at the 4th ventricle what is required to complete staging?
MRI spine and CSF from lumbar spine at least 10 days post resection
What is standard treatment for medulloblastoma?
Resection, craniospinal irradiation with a boost to the resection site bed followed by adjuvant chemotherapy.
Describe posterior fossa syndrome
Difficulty verbalising, excessive irritability, nystagmus, mutism, emotional lability.
Seen in about 20% after resection of medulloblastoma.
What is the management of ependymoma?
Surgical resection and radiation
What is the classic triad seen at presentation of a child with DIPG?
Cerebellar signs (ataxia, dysmetria, dysarthria), long track signs (increased tone, hyperreflexia, clonus, babinski sign, motor deficit), isolated or multiple cranial nerve palsies.
High alpha fetoprotein in germinoma or non-germionomatous germ cell tumours?
Non-germinomatous GCT
Usual management of low grade glioma?
Observation, Complete resection +/- chemotherapy
Rosenthal fibres are pathognomonic for which CNS tumour?
Low grade glioma
Toddler with emaciation, with weight loss despite good oral intake. Also concerns that the child may not be able to see properly. Where is the tumour?
Diencephalus - diencephalic syndrome
What tumours are tuberous sclerosis children predisposed to?
Subependymal giant cell astrocytomas - TSC1 and TSC2
What syndrome predisposes to medulloblastoma?
Gorlin syndrome - PTCH gene
Plexiform fibroma treatment in NF1
Trametinib - MEK Inhibitor
Treatment for subependymal giant cell astrocytoma not resectable?
Everolimus
Chemotherapy that causes sensorineural high frequency hearing loss?
Cisplatin - damages cochlear hair cells
Which region does a mediastinal neuroblastoma arise from?
Posterior
What is the management of tumour lysis syndrome (hyperkalaemia, hyperuraemia, hyperphosphataemia)?
Hyperhydration
Hypouricaemic agents:
- Allopurinol –> Xanthine oxidase inhibitor to halt uric acid production
- Rasburicase (converts urate oxidase to allantoin = more soluble) –> contraindicated in G6PD deficiency
Calcium glutinate –> myocardium protection
Regular electrolyte monitoring
Only treat hypocalcaemia if symptomatic as calcium replacement binding with phosphate can cause worsening renal failure.
Which of the following is the most commonly associated with anaphylaxis?
Asparaginase, vincristine, carboplatin, doxorubicin
Asparaginase
Which of the following is the most likely to cause delayed nausea, 5-FU, Cisplatin, methotrexate, vincristine?
Cisplatin
What is the best prophylactic antiemetic combination for someone receiving highly emetogenic chemotherapy?
Ondansetron, aprepitant (NK 1 receptor antagonist), dexamethasone
Which chemotherapy acts on the M (Mitotic) phase of the cell cycle?
Vincristine
Which chemotherapy agent is related to risk of pancreatitis?
Asparaginase
Which chemotherapy agent can cause constipation?
Vincristine
Which chemotherapy agent does not cause bone marrow toxicity?
Vincristine
Steroid side effects?
HTN
Hyperglycaemia
Gastritis
Weight gain
Proximal myopathy
Behavioural mood disturbance
Reduced bone density
Avascular necrosis
What can be used to prevent cardiac toxicity after doxorubicin?
Dexrazoxane
Which chemotherapy is most likely to cause infertility secondary to gonadal dysfunction?
Alkylating agents such as cyclophosphamide
Which chemotherapy agent can cause encephalopathy hours to days after treatment is initiated?
Ifosfamide - main symptom is generally drowsiness, rarely progressing to coma/seizures
What is the target of rituximab?
CD20 on memory B cells
What stage of the cell cycle does bleomycin act on?
G2
What stage of the cell cycle does asparaginase act on?
G1
What are the two common markers seen on peripheral blood film in those with AML?
MPO and CD7
