Paeds - Oncology Flashcards
Which tumours are only usually seen in kids
EMBRYONAL TUMUORS (inborn changes - hence why it is so rare)
- Wilms
- Neuroblastoma
- Rhabdomyosarcoma
In adults usually caused by DNA mutation caused by environmental exposures over lifetime
Peak incidence for bone tumour/lymphomas
Early adolescence / early adulthood
Leukaemia/Lymphoma kids vs adults
In kids it tends to be acute / high grade
Vice versa in adults
Childhood cancer aet
- Idiopathic (most)
- Double hit theory - Mutations in cellular genes
- Oncogenes + Tumour suppressor genes
- Inherited (Retinoblastoma) or sporadic - Increased risk due to other condition (screened earlier on)
- Downs
- Immunocompromise
- Neurofibromatosis-1
Common presentations of cancer in kids
- LOCALISED MASS
- Lymphadenopathy
- Organomegaly
- Soft tissue/bony mass - Problems from disseminated disease
- Bruising, tiredness, recurrent infections (from bone marrow infiltration) - Problems from localised mass
- Lymphadenopathy, oedema, SOB
Claw sign
When only a little bit of kidney is visible under a big mass - on USS
- Wilm’s
DDx for recurrent fever + bone pain
- Leukaemia (more systemic)
- Arthritis
- Ewing’s (bony)
- Neuroblastoma
Abnormal red reflex can indicate
Retinoblastoma
Reasons for proptosis in kids
- Neuroblastam
- Infection
- Rhabdomyosarcoma
Acute leukaemia Px
- Fever + Fatigue
- Bruising
- Bone pain
- Anaemia (chronic)
- Lymphadenopathy
- FREQUENT INFECTIONS
- hepatospelenomegaly
ALL Ix
- Blood film
- Serum chemistry
- CXR
- Bone marrow aspirate (typically from hip; genetics screen)
- Lumbar puncture (has it spread to brain)
ALL Tx
Chemotherapy (overall keep going for ~ 2yrs to ensure its all gone):
- 2 wks high intensity ‘INDUCTION therapy’ (95% of cells killed)
- CONSOLIDATION
- Interim maintenance
- Delayed intensification
- Maintenance
If high risk / relapsed patients -> Haemopooitic stem cell transplant
CNS tumours Px
- Headache (esp if overnight)
- Vomiting (esp in early morning)
- Papilloedema
- Squint
- Nystagmus
- Ataxia
- Personality / behaviour change
When to scan for a headache
- associated papilloedema
- associated neurological sign
- Recurrent / in early morning
- Associated vomiting
- Decreasing growth
- Sx of diabetes insipidus
- Age < 3 yrs
- Associated Neurofibromatosis 1
CNS tumour Tx
- Surgery
- Resection
- VP shunt (to reduce risk of hydrocephalus) - Chemo
- Single agent or combination - Radiotherapy
- Not used in young kids
- Typically for malignant tumours in older kids
DDx for lymphadenopathy
- Infection (HIV esp is chronic)
- Autoimmune
- Storage disorders (metabolic?)
- Malignancy
When to consider lymph node biopsy
- Enlarged node without clear infective cause / Persistently enlarged
- Unusual site (e.g. supraclavicular)
- Associated Sx
- Fever, wt loss, hepatosplenomegaly - Abnormal CXR
Lymphoma Tx
- Chemo
- Radiotherapy
- Hodgkin’’s in particular - to reduce bulk - Surgery mainly just for biopsy, not curative
- High dose therapy for relapse (hard to treat)
Abdo mass
- Associated pain, haematuria, constipation, HTN, weight loss
- Do USS first
- then CT +/- biopsy
Neuroblastoma Tx
Low risk mainly in infants:
- Surgery (may have chemo after)
High risk metastatic in older kids
- Chemo (High dose if high-risk; other wise based on stage + biology)
- Radiotherapy (mainly for high risk / relapsed)
Wilm’s tumour Tx
- ~6 wks of chemo
- Surgery
- 4 more weeks of chemo
- Partial nephrectomy or translplant if bilateral (careful follow-up) - Radiotherapy (if residual abdo / pulm disease)
Retinoblastoma aet
- RB1 gene mutation
- 40% familial
Late complications of cancer Tx (paeds)
- Endocrine (hormones for growth + development)
- Intellectual impairment
- Cardiac toxicity
- Renal toxicity
- IMPAIRED FERTILITY (consider doing fertility tx before chemo/radio)
- Psych problems (in teens + family members)
Wilm’s tumour epid + type of tumour
Mainly in kids < 5 YEARS
- peaks at 3-4 y/o
- malig embryonic tumour
Common conditions associated w/ Wilm’s
- WAGR syndrome (Wilms’ tumour, Aniridia, Genitourinary anomalies, and mental Retardation)
- Beckwith-Wiedemann syndrome
- Denys-Drash syndrome
Wilm’s Px
- Palpable MASS - usually doesn’t cross midline - but sometimes bilateral
- Abdo DISTENSION / sometimes pain
- HAEMATURIA
- HTN
Oft asymp till it grows too large / disruptive
Wilm’s DDx
- NEUROBLASTOMA - abdo mass which CROSSES MIDLINE +/- systemic Sx
- Mesoblastic Nephroma (haematuria rare)
- Renal cell carcinoma (typically in ADULTS)
Wilm’s Ix
- CT chest, abdo, pelvis (identify spread)
- RENAL BIOPSY (definitive Dx + staging)
- may see small, round, blue cells on histology (non-specific)
Wilm’s Mx
- SUrgical resection (typically unilateral nephrectomy)
- Adjuvent chemo / radio
Depends on stage + hisology
Prognosis >90% 5-year survival
Neuroblastoma
Paediatric cancer of NEURAL CREST cells
- typically in ADRENAL MEDULLA or ABDO SYMPATHETIC chain
- most common cancer in kids < 1
- uncommon > 5 y/o
Neuroblastoma pathophys
Stalled migration of NEURAL CREST cells (derived from ECTODERM) to adrenal medulla / sympathetic chain
- Poorly differentiates + acquires mutations
Linked to MYCN + ALK oncogene mutations + Loss of function of tumour suppressor PHOX2B
RFx for neuroblastomas
No direct identidfiable cause but more likely if child has other neurocristopathies e.g.:
- Hirschsprung’s disease
- Congenital Central Hypoventilation Syndrome
Neuroblastoma Px
Oft non-specific:
- Abdo DISTENSION
- FATIGUE
- Loss of APPETITE
- WEIGHT LOSS - Sx of raised catecholamines (SWEATING, AGITATION)
- Sx of mets ( BONE PAIN, recurrent infections)
- Urinary incontinence if symp chain compressed
- sometimes SOB / chest pain if in thoracic section
Findings on examination suggestive of neuroblastoms
Non-specific:
- Abdo swelling
- Hypertension
- Tachycardia
- Periorbital bruising from mets
- ‘Bluberry muffin’ purpuric rash from dermis mets
- Evidence of bone pain / recurrent infections
Neuroblastoma DDx
Basically ddx for abdo mass:
- Cysts
- Hyperplasia
- Neoplasia
If only blueberry muffin rash -> consider TORCH infection / AML
Neuroblastoma Ix
- HOMOVANILLIC ACID (HVA) + VANILLYLMANDELIC ACID (VMA) in urine
- indicates catecholine breakdown
- raised in 90% - Bone marrow / skin BIOPSY if sign of mets
Imaging:
- USS for point of care identification of lumps
- then MRI
- CXR if THORACIC
Definitive = MIBG scan
- iodine isotope injected
- 2 scans 24hrs apart
- tumour looks v dark on scan as iodine collects there
2 most commonly used to stage neuroblastomas in UK
- International Neuroblastoma Risk Group
- Neuroblastoma Staging System (older - based on surgical observations)
Neuroblastoma Mx
- oft can regress to nothing / benign ganglioma in INFANTS (<18 months / no mets) so just CLOSELY monitor
- Older kids / more aggressive = SURGERY
- curative if L1
- adjuvent chemo/radio if L2 (involves vital structures)
- Consider novel immuniotherapy
(- e.g. against neuroblast cell-surface protein GD2) - SUPPORTIVE CARE
- Analgesia, antiemetics, play therapists etc
What improves prognosis for neuroblastoma
- Younger age at diagnosis
- FEMALE
- Lesser tumour stage at diagnosis
- MYCN mutation absent
Neuroblastoma complications
- 40-50% with high-risk neuroblastoma -> RELAPSE
- Opsoclonus-myoclonus ataxic syndrome (in 2-4% of cases)
- Auto-immune disorder
- Autoantibodies to proteins from dying neuroblasts -> CNS immune reaction esp in CEREBELLUM
- opsiclonus = uncontrolled / irregular eye movement
- myoclonus + ataxia
- confusion + irritability
Causes of retinoblastoma
- HEREDITARY -> germline mutations in RB1 tumour suppressor gene
- NON-HEREDITARY -> somatic mutations in RB1 gene
Mutations to this gene is also associated with risk of other cancers
Retinoblastoma Px
- LEUKOCORIA - white pupil
- Deteriorating vision
- Strabismus (squint)
- FAILURE TO THRIVE
Eye enlargement more common in developing nations
DDx for retinoblastoma
- Congenital cataracts
- Congenital toxoplasmosis (TORCH - chorioretinitis + visual disturbance)
- Congenital Rubella syndrome (salt-and-pepper retinopathy)
- Persistent hyperplastic primary vitreous (leukocoria + MICROphthalmia)
- Retinopathy of prematurity
Retinoblastoma Ix
OPHTHALMIC examination
- indirect opthalmoscopy under anaesthaesia
- Systemic evaluation to rule out mets
- Genetic testing for RB1 mutations
- Imaging for Dx + staging
Retinoblastoma Mx
NEEDS IMMEDIATE intervention
- Radiotherapy / enucleation +/- Chemo
Good prognosis with Tx
