Oncological Emergencies Flashcards
What is neurofibromatosis?
A rare genetic disorder that typically causes benign tumors of the nerves and growths in other parts of the body, including the skin.
What are the 3 types of neurofibromatosis?
- neurofibromatosis 1 (NF1)
- neurofibromatosis 2 (NF2)
- schwannomatosis
What gene is involved in neurofibromatosis 1?
NF1
Inheritance of neurofibromatosis 1 and 2?
Autosomal dominant
What mutation occurs in neurofibromatosis 1?
The NF1 gene provides instructions for making a protein called neurofibromin. This protein is produced in many cells, including nerve cells and specialized cells surrounding nerves (oligodendrocytes and Schwann cells).
Neurofibromin acts as a tumor suppressor, which means that it keeps cells from growing and dividing too rapidly or in an uncontrolled way.
Mutations in the NF1 gene lead to the production of a nonfunctional version of neurofibromin that cannot regulate cell growth and division.
What characteristic sign is seen in neurofibromatosis 1?
Early childhood –> cafe au lait spots
These are flat patches on the skin that are darker than the surrounding area. These spots increase in size and number as the individual grows older. Freckles in the underarms and groin typically develop later in childhood.
What chemical can often cause angiosarcomas?
Vinyl chloride
What cancer can long-term exposure to high levels of benzene in the air lead to?
Leukaemia
What are aromatic amines?
Aromatic amines are chemicals found in industrial and manufacturing plants, tobacco smoke, commercial hair dyes, and diesel exhaust
What type of cancer can exposure to aromatic amines lead to?
Bladder cancer
What type of cancer can exposure to wood dust lead to?
Nasal adenocarcinoma
How can low fibre intake lead to increased risk of colorectal carcinoma?
Increased bowel transit time –> increase carcinogen exposure
What cancer can increased smoked food intake predispose to?
Gastric carcinoma
What cancer can topoisomerase inhibitors (used in chemotherapy) predispose to?
Acute leukaemia
Which HPV strains are most commonly associated with cervical & anal cancer?
16 and 18
Gastric MALT lymphoma is strongly linked to what infection?
H. pylori
Eradication of H.Pylori may lead to tumour regression
What is a MALT tumoiur?
MALT tumours (mucosa-associated lymphoid tissue type of NHL –> most commonly in stomach
What can be asked about in history with a potential cancer patient?
- Pain
- Lumps
- Bleeding e.g. haemoptysis, rectal bleeding, haematuria
- Change in function e.g. bowel habit, cough, dyspnoea, weight loss, fever, confusion
- Socioeconomics e.g. occupation, environmental exposure
- Risk factors e.g. smoking, FHx, PMHx, drugs, diet, alcohol
Describe the TNM staging for cancer
T: Primary Tumour
o TX: Cannot be assessed
o T0: No Evidence
o Tis: Carcinoma in situ
o T1-4: Increasing in size and/or local extent
N: Regional Lymph Nodes
o NX: Cannot be assessed
o N0: No regional lymph node mets
o N1-3: Increasing involvement in lymph nodes
M: Distant Metastasis
o Mx: Cannot be assessed o M0: No distant mets
o M1: Distant mets
What are tumour markers?
- Substances produced either by, or in response to tumour
- Present in blood or other tissue fluids and can be quantified
- Should be both high sensitive and highly specific
Sensitivity vs specificity?
Sensitivity –> ability to detect those with the
disease
Specificity –> ability to accurately define those who are disease free
What conditions can cause an elevated hCG?
Pregnancy
If not pregnant –> raises suspicion of germ cell tumour, particularly choriocarcinoma
Gestational trophoblastic disease (GTD):
- Hydatiform mole
- Choriocarcinoma
- Non-seminomatous testicular cancer
- Seminoma
What is a choriocarcinoma?
Choriocarcinoma is a very rare type of cancer that occurs in around 1 in 50,000 pregnancies. It can develop if the cells left behind after a pregnancy become cancerous. The abnormal cells start in the tissue that would normally become the placenta.
This can happen after any pregnancy, but it’s more likely after molar pregnancies.
Name some oncological emergencies
- Neutropenic sepsis
- Tumour lysis syndrome
- Metastatic spinal cord compression
- Superior vena cava obstruction
- Hypercalcaemia
What is neutropenic sepsis?
N.B. can also be called febrile neutropenia and neutropenic fever
Neutropenic sepsis is defined by NICE as a neutrophil count of 0.5 × 109 per litre or lower, plus one of the following:
1) Temperature ≥ 38°C or
2) Other signs or symptoms consistent with significant sepsis
N.B. The definition of neutropenic sepsis varies between sources. In some hospitals, neutropenic sepsis is diagnosed in patients with a neutrophil count of 1 × 109 per litre or lower.
What is the most common medical emergency amongst oncology and haematology patients?
Neutropenic sepsis
What is the major cause of neutropenic sepsis in cancer patients?
Recent chemotherapy (most commonly within 7 – 10 days) –> causes neutropenia through bone marrow suppression
The risk of neutropenia varies in both severity and timescale between different chemotherapy treatment regime.
Give some other causes of neutropenia:
- Malignant bone marrow infiltration
- Extensive radiotherapy
- Bone marrow failure secondary to non-malignant disease (e.g. aplastic anaemia)
- Hypersplenism
- Megaloblastic anaemia
- Drug-induced (e.g. clozapine)
What drug can induce neutropenia?
Clozapine (atypical antipsychotic)
Risk factors for neutropenic sepsis and associated complications?
- Patients over the age of 60
- Advanced malignancy
- Previous neutropenic sepsis
- Mucositis (chemotherapy can induce mucosal damage and allow bacterial translocation)
- Poor performance status
- Significant co-morbidities (the risk increases further in the presence of multiple co-morbidities)
- Indwelling central venous catheters
- Corticosteroids (causes immunosuppression)
- Prolonged hospital admission
- Severe or prolonged neutropenia
What grading system is used to grade the severity of neutropenia?
Common Terminology Criteria for Adverse Events (CTCAE)
Describe the neutrophil count for grade 1-4 of the CTCAE for neutropenia
Grade 1: >1.5
Grade 2: 1.0-1.5
Grade 3: 0.5-1.0
Grade 4: <0.5
What is the typical presentation of neutropenic sepsis?
Many patients will present from home with isolated pyrexia.
However –> neutropenic sepsis may present without fever in some patients, including older patients and those taking immunosuppressive medications such as steroids.
Therefore, neutropenic sepsis should be considered in any patient at risk of neutropenia who presents unwell, irrespective of temperature.
Symptoms of neutropenic sepsis may be non-specific symptoms of sepsis or reflect the underlying source of infection.
What are some non-specific symptoms of sepsis?
- Fatigue
- Feeling warm or cold
- Rigors or shaking
- Feeling sweaty or clammy
- Palpitations
- Dizziness
- Subjective confusion or disorientation
Some symptoms that may reflect a specific infective source in neutropenic sepsis:
Chest source: shortness of breath, cough, chest pain, sore throat.
Urine source: dysuria, increased frequency, urgency or any other lower urinary tract symptoms.
Skin source: rashes, blisters, pain.
Gastrointestinal source: diarrhoea, nausea, vomiting, rectal bleeding, abdominal pain, sore mouth (due to mucositis).
Indwelling line source: pain around the line or rigors after use of the line.
What is important to cover in patient history in potential neutropenic sepsis?
- Symptoms
- Past medical history (e.g. details of cancer diagnosis including previous treatments)
- Chemotherapy history (e.g. type of chemotherapy, date of the most recent cycle)
- Drug history (e.g. steroids, antibiotic prophylaxis, granulocyte-colony stimulating factor use and details of any allergies)
- Recent procedures which may
predispose to infection (e.g. placement of an indwelling vascular access device) - Previous episodes of pyrexia or neutropenic sepsis (to guide the identification of a source or causative organism)
What approah should patients with neutropenic sepsis be examined with?
ABCDE approach
Patients with neutropenic sepsis are at risk of sudden deterioration. The initial examination should focus on determining how unwell the patient is and establishing what immediate care they require.
What are some general clinical findings in neutropenic sepsis?
A
B
- Respiratory rate –> tachypnoea
- O2 sats –> hypoxia
C
- Blood pressure –> hypotension
- Heart rate –> tachycardia
- Fluid balance –> reduced urine output
D
- Consciousness –> reduced
E
- Temperature –> pyrexia
- Mottled/ashen appearance
It is important to remember that examination findings are often MINIMAL in neutropenic sepsis.
Other potential findings:
Chest source: increased work of breathing, crepitations, dullness to percussion, reduced air entry.
Urine source: suprapubic or flank pain, cloudy urine in catheter bag (if applicable).
Skin source: rashes, blistering, tenderness.
Gastrointestinal source: abdominal tenderness, dehydration (if reporting vomiting or diarrhoea), evidence of oral mucositis, jaundice.
Indwelling line source: surrounding erythema, tenderness on palpation, pain or rigors on flushing.
Differential diagnoses of neutropenic sepsis?
The most common cause of a fever in cancer patients is an infection, with or without neutropenia.
Other causes of fever to consider include:
- Underlying malignancy (both solid and haematological)
- Immunotherapy toxicities
- Inflammatory disorders (e.g. SLE, vasculitis, rheumatoid arthritis)
- Drug-induced
- Hypothalamic dysfunction
- Thyroiditis
What are most cases of neutropenic sepsis caused by?
Underlying bacterial infection (but also important to consider viral and fungal infections)
What are the most common gram-negative bacilli seen in neutropenic sepsis?
Can all produce extended-spectrum beta-lactams:
- E. coli
- Klebsiella spp.
- Pseudomonas aeruginosa
- Enterobacter spp.
- Proteus spp.
What are the most common gram-positive bacilli seen in neutropenic sepsis (more common)?
- Staphylococcus aureus (including methicillin resistant – MRSA)
- Coagulase-negative staphylococci (eg. Staphylococcus epidermidis)
- Streptococcus pneumoniae
- Viridans group streptococci
- Enterococcus spp. (including vancomycin-resistant types – VRE)
- Group A streptococci
What fungi can cause neutropenic sepsis?
- Candida spp.
- Aspergillus spp.
- Mucorales
What should form a critical part of the assessment of a patient with neutropenic sepsis?
Reviewing previous microbiological results as this may help identify an underlying cause and guide treatment.
Investigations will depend on the clinical context and the suspected source of infection in neutropenic sepsis.
What bedside investigations may be done?
Urinalysis: to look for urinary tract infection.
ECG: should be performed in all acutely unwell patients.
Capillary blood glucose: to exclude hypoglycaemia.
Investigations will depend on the clinical context and the suspected source of infection in neutropenic sepsis.
What lab investigations may be done?
Baseline blood tests (FBC, U&E, coagulation, CRP, LFTs): white cells may be low or raised and CRP may also be raised.
Serum lactate: performed as part of the sepsis six care bundle.
Group and save: the patient may require a blood transfusion.
Blood cultures: at least two sets from a peripheral vein plus a set from an indwelling line if present to look for a causative organism.
Arterial blood gas: to assess the extent and severity of any respiratory failure.
Microbiological cultures: wounds, urine, stool, sputum, and line tip (if indwelling line infection suspected).
Viral respiratory swab: if viral respiratory infection suspected.
Investigations will depend on the clinical context and the suspected source of infection in neutropenic sepsis.
What imaging investigations may be done?
- Chest X-ray: to look for evidence of pneumonia.
- High-resolution chest CT: if fungal pneumonia is suspected.
- Abdominal ultrasound or CT abdomen: if biliary or abdominal infection suspected.
What investigation should be done if an atypical chest source is suspected, such as Pneumocystis jirovecii?
Bronchoalveolar lavage
Management of neutropenic sepsis?
1) Patients with suspected or confirmed neutropenic sepsis should receive EMPIRICAL ANTIBIOTIC THERAPY within ONE HOUR of arrival at hospital. Antibiotic therapy must NOT be delayed to wait for confirmation of neutropenia.
2) The SEPSIS SIX care bundle should be completed.
What is the empirical antibiotic therapy for neutropenic sepsis?
Local guidelines regarding the choice of antibiotic therapy must always be followed. If in doubt, seek advice from microbiology.
1st line –> usually IV piperacillin with tazobactam (Tazocin)
2nd line (e.g. penicillin allergy) –> may include intravenous meropenem although this will depend on local guidelines.
Additional anti-microbial cover –> (e.g. teicoplanin) for gram-positive organisms may be required for patients with indwelling central venous catheters.
Anti-fungal treatment –> may be considered when the fever persists beyond 4 – 6 days.2,5
Specimens for microbiological culture should ideally be taken BEFORE commencing antibiotic therapy however this should NOT delay treatment.
If low risk neutropenic sepsis, can give oral antibiotics.
What Abx are given?
Usually quinolone + co-amoxiclav
What features may suggest low risk neutropenic sepsis?
- hemodynamically stable
- does not have acute leukaemia
- no organ failure
- no soft tissue infection
- no indwelling lines
What can be used or both prophylaxis and treatment of neutropenia to reduce the risk of neutropenic sepsis?
Recombinant granulocyte-colony stimulating factor (G-CSF)
What is G-CSF?
Works by stimulating the bone marrow to produce neutrophils and may form part of specific chemotherapy regimens.
What is an example of a G-CSF drug?
Filgrastim
Compliations of neutropenic sepsis?
Single or multi-organ failure (e.g. renal failure, heart failure and acute respiratory distress syndrome)
Venous thromboembolism (e.g. pulmonary embolism)
Disseminated intravascular coagulation
Opportunistic or hospital-acquired infections
Delirium
Psychological complications (e.g. anxiety regarding future infections and chemotherapy treatment)
Delays in chemotherapy leading to worse cancer outcomes
Risk of mortality of neutropenic sepsis?
10%
What is a malignant spinal cord compression (MSCC)?
A medical emergency caused by compression of the spinal cord or cauda equina
Characterised by compression or displacement of arterial, venous, and cerebrospinal fluid spaces, including the spinal cord itself.