Oncology Flashcards
What are Proto-oncogenes ??
They play an important physiological role in cellular growth & differentiation
- Oncogenes are derived from this
- ‘Gain of Func.” results in an increased risk of cancer; only 1 mutated copy is needed (a Dominant effect)
Through what processes do Proto-oncogenes become an Oncogene ??
Mutation (Point mutation)
Chromosomal translocation
Increased Protein Expression
Name cancers a/w EBV ??
Burkitt’s Lymphoma
Hodgkin’s Lymphoma
Post Transplant Lymphoma
Nasopharyngeal CA
Name the Cancers a/w Human Papilloma Virus 16/ 18 ??
Cervical cancer
Anal Cancer
Penile Cancer
Vulval Cancer
Oropharyngeal Cancer
Name the Cancers a/w the following viruses
- Human Herpes Virus 8
- HBV
- HCV
- Human T- Lymphotropic virus 1 (HTLV1)
- Kaposi’s Sarcoma
- HCC
- HCC
- Tropical Spastic Paraparesis & Adult T cell Leukaemia
What are Tumour Suppressor Genes ??
Genes which control the normal cell cycle
- Loss of func. leads to increased risk of cancer
- BOTH alleles must be mutated before Ca occurs
Examples of Tumour Suppressor Genes ??
- p53: Common to many Cancers, Li-Fraumeni synd.
- APC: Colorectal Cancer
- BRCA1 & BRCA2: Breast & Ovarian Ca ; In men increased risk of Breast & Prostate cancer
NF1: Neurofibromatosis
Rb: Retinoblastoma
WT1: Wilm’s tumour
Multiple Tumour Suppressor 1 (MTS-1, p16) : Melanoma
What is p53 ??
Tumour Suppressor Gene on Chr 17p
- MC mutated gene in Breast, Colon, Lung cancer
- Plays a crucial role in Cell cycle- preventing entry into S phase
- Key regulator of Apoptosis
What is Li-Fraumeni syndrome ??
- A D disorder
- Early onset of variety of cancers such as Sarcoma, Breast Ca, Leukaemias
- Caused by p53 mutation
Which brain tumours produce
- Late symptoms ??
- Early symptoms ??
- Rt. Temporal & Frontal lobe tumours reach considerable size before becoming symptomatic
- Tumours in the Speech & Visual areas, typically produce Early symptoms
Types of CNS tumours ??
Glioma & Metastatic disease (60%)
Meningioma (20%)
Pituitary lesions (10%)
Dx.- MRI scan
In Paediatrics: Medulloblastoma (Neuroendocrinal tumour) were the commonest; ASTROCYTOMA now accounts for the majority
Indications for Temporal Artery Biopsy ??
Superficial Temporal A is a terminal branch of External C A
Temporal Arteritis
- Age of onset > 50 yrs
- New onset Headache/ Localized Head pain
- Temporal artery tenderness on palpation or Reduced pulsation
- ESR > 50 mm/hr
Procedure of T A biopsy ??
- Position: Supine, Head 45 degrees
- USS doppler to locate the artery or Palpate
- Local Anaesthesia
- Artery within Temporoparietal fascia
- Clamp & Ligate the vessel
- Cut 3 to 5 cms
- Ligate the remaining ends with Absorbable suture
- Close the skin
Histopathology of Temporal artery biopsy in T Arteritis ??
Vessel wall Granulomatous arteritis with Mononuclear cell infiltrates & Giant cell formation
What is the CI for Temporal A Biopsy
& the risk involved with the procedure ??
- Glucocorticoid Therapy for > 30 days
- Injury to Facial & Auriculotemporal Nerve
Main frameworks used to tackle pts. who refuse Rx. ??
COMMON law: Used to treat pts. in Emergency scenarios
Mental CAPACITY Act (MCA)
- Used in pts. who require Rx. for physical disorders that affects brain func.
- Eg.- Delirium secondary to sepsis, Dementia
Mental HEALTH Act (MHA)
- Used in pts. with Mental disorder
- In pts. who are already admitted, a section 5(2) is used if this is not the time for more formal section 2 or 3
- Eg.- Pt. with mental disorder + Attempting to discharge themselves (when it is thought it may harm the pt.)
MC sites of Brain tumour in
- Adults ??
- Childhood ??
- Supratentorial
- Infratentorial
MC Metastatic brain tumours ??
MC form of Brain tumour
- Lung Cancer (most common)
- Breast
- Bowel
- Skin (Melanoma)
- Kidney
What is Glioblastoma multiforme ??
MC primary tumour in adults & is a/w poor prognosis (1 year)
- Solid tumour + Central necrosis & a rim that enhances with contrast
- Disruption of BBB => a/w Vasogenic Oedema
- HP: Pleomorphic tumour cells border necrotic areas
Rx: Sx + Post-Op. CT & RT
DEXAMETHASONE to treat Edema
What is Meningioma ??
2nd MC primary brain tumour in adults
- Benign, extrinsic tumours of CNS
- Origin: Arachnoid cap cells of meninges
- Site: Next to Dura; Falx cerebri, Superior sagittal sinus, Convexity or Skull base
- HP: Spindle cells in concentric whorls + Psammoma bodies-calcified
C/F - Compression symptoms rather than Invasion
Rx.- Observation, RT & Sx. resection
What is Vestibular Schwannoma ??
aka Acoustic Neuroma is a benign tumour arising from 8th CN
- Site: CP angle
- NF-2 is a/w B/L V S
- HP: Antoni A or B pattern is seen. Verocay bodies- Acellular areas surrounded by nuclear palisades
- C/F: D V T, SNHL, Facial N palsy, Corneal reflex absent
Rx.- Observation, RT, Sx.
MC primary brain tumour in Children ??
PILOCYTIC ASTROCYTOMA
- HP: Rosenthal fibres (Corkscrew Eosinophillic bundle)
What is Medulloblastoma ??
Aggressive paediatric brain tumour
- Site: Infratemporal compartment
- Spread: CSF system
- HP: Small, blue cells. Rosette pattern of cells with many mitotic figures
What is Ependymoma ??
Primary brain tumour which is a type of Glioma that starts from Ependymal cells
- Site: 4th ventricle
- May cause Hydrocephalus
- HP: Perivascular Pseudorosettes
