Cerebral tumors 1


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Cerebral tumors 1

  1. 1. Presenter: Dr. Sabir Ahmed Chairperson: Dr. S.D. Kshirsagar
  2. 2. <ul><li>A wide variety of tumors affect the brain and spine. </li></ul><ul><li>Primary benign and malignant tumors arise from the various elements of the CNS, including neurons, glia, and meninges. Tumors metastasize to the CNS from many primary sources. </li></ul><ul><li>Presentation varies widely depending on relevant neuroanatomy. Prognosis depends on histology and anatomy </li></ul><ul><li>Modern brain tumor centers use team approaches to CNS tumors, as patients may require a combination of surgery, radiation therapy, chemotherapy and research protocol enrollment. </li></ul>
  3. 3. <ul><li>Nervous system may be divided into </li></ul><ul><li>Central nervous system </li></ul><ul><li>- brain </li></ul><ul><li>- spinal cord </li></ul><ul><li>peripheral nervous system </li></ul><ul><li>- peripheral nerves </li></ul><ul><li>- ganglia </li></ul><ul><li>The brain consists of </li></ul><ul><li>(i) the cerebrum comprising 2 large cerebral hemisphere </li></ul><ul><li>(ii) the cerebellum </li></ul><ul><li>(iii) brainstem </li></ul><ul><li>- midbrain </li></ul><ul><li>- pons </li></ul><ul><li>- medulla </li></ul>
  4. 6. <ul><li>Gray matter and white matter: section through brain show certain regions that are whitish and others that have darker greyish colour. This contitute white matter and grey matter respectively. </li></ul>
  5. 7. <ul><li>The cerebrum made up of 2 cerebral hemispheres, partially separeted from each other by the median longitudinal fissure. </li></ul><ul><li>The 2 hemispheres are connected to each other by corpus callosum </li></ul><ul><li>Each ventricle contains a cavity, called the lateral ventricle. </li></ul>
  6. 8. <ul><li>Each cerebral hemisphere is </li></ul><ul><li>divided into 4 lobes- </li></ul><ul><li>Frontal 3 </li></ul><ul><li>Parietal </li></ul><ul><li>Occipital </li></ul><ul><li>Temporal </li></ul><ul><li>The sulci separating the lobes on this surface are </li></ul><ul><li>1. Central sulcus: separating frontal and parietal lobe </li></ul><ul><li>2. Lateral sucus: separating temporal lobe from frontal and parietal lobe </li></ul><ul><li>3. parieto-occipital sulcus: is a sulcus of medial surface, separating occipital from parital lobe </li></ul><ul><li>4. Preoccipital notch: is an indentation on the inferolateral border. </li></ul><ul><li>2 1 </li></ul><ul><li>3 </li></ul><ul><li>4 </li></ul>
  7. 17. <ul><li>Duramatter </li></ul><ul><li>Arachnoid matter </li></ul><ul><li>Pia matter </li></ul>
  8. 18. <ul><li>The specialized cells that constitute the nervous syatem are called –nurone. </li></ul><ul><li>Nurones are supported by special kind of connective tissue called- neuroglia </li></ul>
  9. 19. <ul><li>Neuron consist of </li></ul><ul><li>- cell body which gives off variable number of processes. </li></ul><ul><li>- most neurons give off a number of short branching called dendrites and one longer process called axon. </li></ul><ul><li>In case of peripheral nerves </li></ul><ul><li>Most axons surrounded by myelin sheath, formed by </li></ul><ul><li>- Schwann cells </li></ul><ul><li>In CNS axons surrounded by neuroglial cells </li></ul><ul><li>- oligidendrocytes </li></ul><ul><li>Functional differences between axon & dendrites </li></ul>axon dendrites In an axon nerve impulse travels away from cell body Nerve impulse travels towards the cell body
  10. 20. <ul><li>Astrocytes </li></ul><ul><li>Microglia </li></ul><ul><li>Oligodendrocytes </li></ul><ul><li>Astrocytes : </li></ul><ul><li>These are star shaped cells present in all part of the brain </li></ul><ul><li>Types </li></ul><ul><li>1. fibrous astrocytes- (present in white matter) </li></ul><ul><li>2. protoplasmic astrocytes- (present in gray matter) </li></ul><ul><li>Microglia: </li></ul><ul><li>These are the phagocytic cells which enters the tissues of nervous system from blood. </li></ul><ul><li>Oligodendrocytes: </li></ul><ul><li>These are the cells forming myelin sheath around the nerve fibers in central nervous system </li></ul>
  11. 22. <ul><li>Although either benign or malignant, almost all brain tumours are malignant in the sense that they may lead eventually to death if not treated. </li></ul><ul><li>In general, the incidence of primary brain tumors is higher in whites than in blacks, and mortality is higher in males than in females. </li></ul><ul><li>Brain tumours are responsible for 2 per cent of all cancer deaths. </li></ul><ul><li>The incidence varies with age. In children tumours of the CNS comprise 20 per cent of all childhood malignancies. There is a peak at 2 years followed by a decline for the rest of the first decade. The incidence then slowly increases, peaking at 20 per 100 000 in late adulthood. </li></ul>
  12. 23. <ul><li>Intracranial tumour can be classified in different ways: primary versus secondary, paediatric versus adult, by cell of origin, or by location in the nervous system. </li></ul><ul><li>Classification of brain tumour (according to cell of origin) </li></ul><ul><li>Neuroepithelial metastatic meningioma pituitary </li></ul><ul><li>Tomour tumour tumour tumour </li></ul><ul><li>50% 15% 15% 8% </li></ul>
  13. 24. <ul><li>Neuro epithelial tumours </li></ul><ul><li>gliomas </li></ul><ul><li>- astrocytomas </li></ul><ul><li>- oligodendroglioma </li></ul><ul><li>- ependymoma </li></ul><ul><li>- choroid plexus tumour </li></ul><ul><li>pineal tumours </li></ul><ul><li>nuronal tumours </li></ul><ul><li>- ganglioglioma </li></ul><ul><li>- gangliocytoma </li></ul><ul><li>- neuroblastoma </li></ul><ul><li>medulloblastoma </li></ul><ul><li>Nerve sheath tumours </li></ul><ul><li>- acoustic neuroma </li></ul><ul><li>Meningeal tumours </li></ul><ul><li>- meningioma </li></ul><ul><li>Pituitary tumours </li></ul><ul><li>- germ cell tumour </li></ul><ul><li>- germinoma </li></ul><ul><li>- teratoma </li></ul><ul><li>Lymphoma </li></ul><ul><li>Tumour like malformations </li></ul><ul><li>- craniopharyngioma </li></ul><ul><li>- epidermoid tumour </li></ul><ul><li>- dermoid tumour </li></ul><ul><li>- colloid cyst </li></ul><ul><li>Metastatic tumours </li></ul><ul><li>Contageous extention from regional tumour: </li></ul><ul><li>- glomus tumour </li></ul>
  14. 25. <ul><li>Chromosomal anomalies: von Recklinghausen’s disease </li></ul><ul><li>Immunosuppression: primary CNS lymphoma </li></ul><ul><li>Addition of oncogenes in genome and loss of normally occurring tumour suppresser genes. </li></ul><ul><li>Mutation in p53 tumour suppresser gene: astrocytoma and meningioma </li></ul><ul><li>Cranial irradiation: for tenia capitis leads to astrocytoma and meningioma </li></ul>
  15. 26. supratentorial adults % Children(<15yrs % Anaplastic astrocytoma 347 40 5 7 meningioma 134 15 - - Metastasis 105 12 - - astrocytoma 73 8 5 7 Pituitary adenoma 31 4 - - craneopharyngioma 13 1 9 13 oligodendroglioma 9 1 1 1 Colloid cyst 4 <1 - - lymphoma 2 <1 - - others 11 1 6 9
  16. 27. Infratentorial adults % Children % neuroma 50 6 - metastasis 39 4 - haemangioblastoma 17 2 - astrocytoma 12 1 19 27 meningioma 12 1 - medulloblastoma 6 <1 17 24 Dermoid/ epidermoid 3 <1 1 1 ependymoma 4 6 others 8 1 3 3
  17. 28. <ul><li>Symptoms tend to develop insidiously, gradually progressing over few weeks or years. </li></ul><ul><li>Occasionally tumour present acutely due to haemorrhage or the development of hydrocephalus. </li></ul><ul><li>supratentorial infratentorial </li></ul><ul><li>tumour tumour </li></ul><ul><li>sings and symptoms </li></ul><ul><li>Mass of ICP and brain shift CSF </li></ul><ul><li>Effects outflow </li></ul><ul><li>tentorial tonsillar obstruction </li></ul><ul><li>herniation herniation </li></ul><ul><li>Focal epilepsy </li></ul><ul><li>Damage </li></ul><ul><li>damage function </li></ul><ul><li>Cr N. damage I-VI cerebral cerebellar Cr N. damage III- XII </li></ul>
  18. 29. <ul><li>Raised intracraneal pressure- headache(morning & progressive), papilloedema(disturbance of vision) </li></ul><ul><li>Brain shift – vomiting, deteration of conscious level, pupillary dilatation </li></ul>
  19. 30. <ul><li>Epilepsy – generalised, partial(simple or complex), partial progressing to genarelised. </li></ul><ul><li>Partial motor seizures partial sensory seizures </li></ul><ul><li>origin- motor cortex origin – sensory cortex </li></ul><ul><li>Tonic/clonic seizures numbness tingling in </li></ul><ul><li>In contralateral face and limb </li></ul><ul><li>Face and limbs </li></ul><ul><li>pure visual/auditory </li></ul><ul><li>seizures are rare </li></ul><ul><li>complex partial seizures: arise from the </li></ul><ul><li>medial temporal lobe- formed visual or auditory </li></ul><ul><li>hallucinations, awareness of abnormal taste, </li></ul><ul><li>feeling of fear, déjà vu, unfamiliarity and </li></ul><ul><li>depersonalisation and automatisms. </li></ul>
  20. 31. <ul><li>Disturbed function: </li></ul><ul><li>Supratentorial </li></ul><ul><li>Higher cortical dysfunction </li></ul><ul><li>before knowing higher cortical dysfunction we should know normal function of cortex. </li></ul><ul><li>Right and left hemisphere function:- </li></ul><ul><li>left hemisphere is dominant in right handed person </li></ul><ul><li>left hemisphere is dominant in left handed person(in 75% of cases). </li></ul><ul><li>language </li></ul><ul><li>R L language dependent memory </li></ul><ul><li>Visual and </li></ul><ul><li>spatial perception </li></ul><ul><li>Visual(non language dependent memory) </li></ul>
  21. 32. Frontal lobe function Impairment of frontal lobe function Precentral gyrus: motor cortex, contralateral movement- face arm trunk leg. Prefrontal gyrus:- monoplegia/ hemiplegia depending on the extent of damage Broca’s area: dominent hemisphere expressive centre for speech. Broca’s are:- broca’s dysphasia Supplimentary moter area: contralateral head and eye turning. Supplimentary motor area : paralysis of head and eye movement to opposite side. Head & eye turn towards diseased hemisphere Prefrontal area:- personality, initiative Prefrontal area:- change of personality with antisocial behaviour/loss of inhibition. Disturbance of gait- gait apraxia. 3 prefrontal syndrome- orbitofrontal syndrome, frontal convexity syndrome, medial frontal syndrome. Paracentral lobule:- cortical inhibition of bladder and bowel voiding Paracentral lobule:- incontinence of urine and faeces. Loss of cortical inhibition
  22. 33. Parietal lobe function Impairment of parietal lobe function Sensory cortex: (represents similar to motor cortex) ---receives afferent pathways for - appreciation of posture - touch - passive movement Contraleteral disturbances of cortical sensation - postural sensation disturbed - sensation of passive movement disturbed - accurate localization of light touch disturbed - 2 point discrimination disturbed - asterognosis Supramarginal angular gyrus: (dominant hemisphere) - Wernicke’s language area - receptive area where auditory , visual aspect of comprehension are integrated. <ul><li>Supramarginal angular gyrus : (dominant hemisphere) </li></ul><ul><li>Gerstmann’s syn </li></ul><ul><li>confusion of right & left limb. </li></ul><ul><li>Finger agnosia </li></ul><ul><li>Acalculia </li></ul><ul><li>Agraphia </li></ul>Supramarginal angular gyrus: (non dominant hemisphere) - concept of body image - awareness of external movement - skills of handling numbers/calculation - visual pathway (optic radiation pass through parietal lobe) <ul><li>Supramarginal angular gyrus: (non dominant hemisphere) </li></ul><ul><li>Unaware of opposite limbs </li></ul><ul><li>Anosognosia </li></ul><ul><li>Geographical agnosia </li></ul><ul><li>Constitutional apraxia: </li></ul><ul><li>cannot copy geometric pattern </li></ul><ul><li>Damage of optic radiation: lower homonymous quadranopia </li></ul>
  23. 34. Temporal lobe function Impairment of function Auditory cortex: dominant lobe: hearing of language no dominant lobe: hearing of sound, rhythm, music. Auditory cortex: dominant lobe: cortical deafness nondominant lobe: amusia Middle and inferior temporal gyri: - learning - memory Middle and inferior temporal gyri: - disturbance of –memory - learning - complex partial seizures - post ictal amnesia Limbic lobe: - sensation of olfaction - emotional/effective behaviour Limbic lobe: - olfactory hallucination with complex partial seizures - aggressive emotional behaviour - inability to establish new memories. Visual pathway: - deep in temporal lobe Visual pathway: upper homonymous quadranopiap
  24. 35. Occipital lobe function Impirement ofOccipital lobe function Visual cortex : striate cortex Visual cortex : homonymous hemianopia with sparing of macula Cortical blindness with preservation of light reflex. Visual cortex : parastriate cortex Visual cortex : parastriate cortex Balint syndrome: (BL parieto occipital lesion) inability to direct voluntary gage, associated with visual agnosia Visual illusion: micropsia- object appear smaller macropsia- object appear larger Prosapagnosia: ( occipito-temporal jn.) patient can see but cannot name familial face. Anton syndrome: involvement of both striate cortex & parastriate cortex impairment of vision patient unaware of visual loss
  25. 37. <ul><li>Chest Xray </li></ul><ul><li>ESR for metastatic workup </li></ul><ul><li>Skull Xray: </li></ul><ul><li>Calcification </li></ul><ul><li>- oligodendroglioma </li></ul><ul><li>- meningioma </li></ul><ul><li>- craniopharyngioma </li></ul>
  26. 38. <ul><li>Skull Xray: </li></ul><ul><li>2. sings of raised intracranial pressure: </li></ul><ul><li>-suture separation(diastasis) </li></ul><ul><li>- “beaten brass” appreance </li></ul>
  27. 39. <ul><li>Skull Xray: </li></ul><ul><li>3. osteolytic lesion; </li></ul><ul><li>primary/secondary bone tumour. </li></ul><ul><li>- dermiod/epidermoid </li></ul><ul><li>- chordoma </li></ul><ul><li>- nasopharyngeal carcinoma </li></ul><ul><li>- myeloma </li></ul><ul><li>- reticulosis </li></ul>
  28. 40. <ul><li>Skull Xray: </li></ul><ul><li>4. erosion of posterior clinoids </li></ul><ul><li>- due to local pressure </li></ul><ul><li>- craniopharyngioma </li></ul><ul><li>5. Pineal shift in Towne’s view </li></ul>
  29. 41. <ul><li>CT scanning </li></ul><ul><li>Effect on adjacent bone </li></ul><ul><li>- meningioma </li></ul><ul><li>- hyperostosis </li></ul>
  30. 42. <ul><li>CT scanning </li></ul><ul><li>single or multiple lesions </li></ul><ul><li>- if multiple metastasis </li></ul>
  31. 43. <ul><li>CT scanning </li></ul><ul><li>effect of contrast enhancement </li></ul><ul><li>none- low grade astrocytoma </li></ul><ul><li>irregular- malignant astrocytoma </li></ul><ul><li>homogenous- meningioma </li></ul>
  32. 44. <ul><li>CT scanning </li></ul><ul><li>mass effect: </li></ul><ul><li>- midline shift </li></ul><ul><li>- ventricular compression </li></ul><ul><li>- hydrocephalus </li></ul><ul><li>(secondary to 3 rd ventricular of posterior fossa lesion </li></ul>
  33. 45. <ul><li>High definition scan: </li></ul><ul><li>indication </li></ul><ul><li>- pituitary </li></ul><ul><li>- orbital </li></ul><ul><li>- posterior fossa tumour </li></ul><ul><li>- tumour of skull base </li></ul><ul><li>Coronal and sagital reconstruction </li></ul><ul><li>- useful in diagnosing vertical extent of the tumour </li></ul><ul><li>- and its relationship with other structure </li></ul>
  34. 46. <ul><li>MRI </li></ul><ul><li>indication </li></ul><ul><li>- tumours around the skull base </li></ul><ul><li>- craneocervical junction </li></ul><ul><li>- brainstem </li></ul><ul><li>Advantage of MRI </li></ul><ul><li>-coronal and sagital section gives </li></ul><ul><li>- exact anatomical relationship to the sulci and gyri, ventricles, the falx and tentorium cerebelli. </li></ul><ul><li>- paramagnetic enhancement </li></ul><ul><li>- IV gadolinium increases sensitivity of detection and clarifies the site of origin. </li></ul><ul><li>- delineate the border between tumour and surrounding edema </li></ul><ul><li>- MRI appears more sensitive than CT scanning in identifying </li></ul><ul><li>- small tumours </li></ul><ul><li>- multiple lesions- metastasis </li></ul>
  35. 47. <ul><li>Angiography/ MRA: </li></ul><ul><li>reveal </li></ul><ul><li>- tumour ‘blush’ </li></ul><ul><li>- vessel displacement </li></ul><ul><li>- preoperative information </li></ul><ul><li>- for identifying feeding to vascular tumours </li></ul><ul><li>- tumour involvement and constriction of major vessels. </li></ul>
  36. 48. <ul><li>CSF examination: </li></ul><ul><li>lumber puncture is contraindicated in cerebral tumours. </li></ul><ul><li>if CSF is obtained by another sources </li></ul><ul><li>- ventricular drainage </li></ul><ul><li>- or shunt insertion </li></ul><ul><li>then cytological examination may reveal tumour cells </li></ul>
  37. 49. <ul><li>Tumour markers: </li></ul><ul><li>Glial Fibrillary Acidic Protein(GFAP) </li></ul><ul><li>- for glial tumours </li></ul><ul><li>Cytokeratin </li></ul><ul><li>Epithelial Membrane Antigen(EMA) for metastatic carcinoma </li></ul><ul><li>Epidermal Growth Factor- differentiate between </li></ul><ul><li>- high grade & low grade tumour </li></ul><ul><li>- </li></ul>
  38. 50. <ul><li>Steroid therapy: </li></ul><ul><li>- to reduce edema surrounding the intracranial tumour. </li></ul><ul><li>- sellar/paraseller tumour occasionally present with steroid insufficiency. In these cases steroid cover is an essential prerequisite </li></ul><ul><li>of any anesthetic and operative procedure. </li></ul><ul><li>Dose: </li></ul><ul><li>- A loading dose of 12mg IV dexamethasone </li></ul><ul><li>- followed by 4mg qid. </li></ul><ul><li>- after several days of treatment, gradual dose reduction </li></ul><ul><li>minimizes the risk of unwanted side effects. </li></ul>
  39. 52. <ul><li>Operative management: </li></ul><ul><li>Approaches </li></ul><ul><li>Craniotomy:- flap of bone is cut and reflected. </li></ul><ul><li>- If necessary, combined with either a stereotactic frame </li></ul><ul><li>- or preferably an image guided system(frameless, steriotaxy) to give accurate lesion localisation </li></ul>
  40. 53. <ul><li>Burr hole surgery: </li></ul><ul><li>For stereotactic or handheld, USG guided biopsy </li></ul>
  41. 54. <ul><li>Transphenoidal route: </li></ul><ul><li>indication- pituitary surgery </li></ul><ul><li>through the sphenoid sinus to the pituitary </li></ul>
  42. 55. <ul><li>Transoral route: </li></ul><ul><li>Indication: </li></ul><ul><li>- brain stem surgery </li></ul><ul><li>- upper cervical cord surgery </li></ul><ul><li>- neurofibroma </li></ul><ul><li>- chordoma </li></ul><ul><li>Method: removal of arch of atlas, odontoid peg </li></ul><ul><li>and clivus provide access to anterior aspect of brain </li></ul>
  43. 56. <ul><li>Operative procedure: </li></ul><ul><li>The subsequent procedure </li></ul><ul><li>biopsy partial tumour removal internal decompression complete removal </li></ul><ul><li>Depends on the nature of the tumour & site. </li></ul><ul><li>Primary malignant tumour : complete removal of tumour is not possible due to its infiltrative nature. So operation is restricted to - biopsy </li></ul><ul><li>- tumour decompression </li></ul><ul><li>Complete removal is done for </li></ul><ul><li>- meningioma </li></ul><ul><li>- craniopharyngioma </li></ul>
  44. 57. <ul><li>Radiotherapy : </li></ul><ul><li>- Megavoltage xray </li></ul><ul><li>- gamma rays from cobalt60. </li></ul><ul><li>- electron beam from linear accelerator. </li></ul><ul><li>- accelerated particles from a cyclotron </li></ul><ul><li>(e.g. neutrons, nuclei of helium, protons) </li></ul><ul><li>Effect of radiotherapy – depends on total dose(usually upto 60Gy) and duration of therapy. </li></ul>
  45. 58. <ul><li>Radiotherapy : </li></ul><ul><li>Aim : to provide highest possible dose to the specific region, while minimal irradiation to adjacent normal brain. </li></ul><ul><li>Indication: </li></ul><ul><li>In malignant tumour: </li></ul><ul><li>- malignant astrocytoma </li></ul><ul><li>- metastasis </li></ul><ul><li>- medulloblastoma </li></ul><ul><li>- germinoma </li></ul><ul><li>In benign tumours </li></ul><ul><li>- pituitary adenoma </li></ul><ul><li>- craniopharyngioma </li></ul>
  46. 59. <ul><li>Radiotherapy : </li></ul><ul><li>Method : </li></ul><ul><li>Stereotactic irradiation: </li></ul><ul><li>Multiple covering beams from a linear accelerator or from multiple cobalt sources </li></ul><ul><li>focused on a selected target </li></ul>
  47. 60. <ul><li>Radiotherapy : </li></ul><ul><li>2. Interstitial techniques: </li></ul><ul><li>Tumour is treated from within(brachytherapy) </li></ul><ul><li>- by implantation of multiple radioactive seeds. e.g. iodine125. </li></ul><ul><li>3. Conformal therapy: </li></ul><ul><li>- standard radiotherapy is administered </li></ul><ul><li>- beam are shaped by use of variable collimeters/blocks. </li></ul>
  48. 61. <ul><li>Radiotherapy : </li></ul><ul><li>4. Whole neural axis irrediation: </li></ul><ul><li>indication: </li></ul><ul><li>- for tumour spread through CSF </li></ul><ul><li>- medulloblastoma. </li></ul><ul><li>Complication of radiotherapy: </li></ul>Increased edema During treatment Reversible demylination After weeks or months Usually reversible radionecrosis In usually 1-2 yrs(range from 6m-10yrs) irreversible
  49. 62. <ul><li>Drugs commonly used: - nitrosoureas </li></ul><ul><li>- Procarbazine </li></ul><ul><li>- Vincristine </li></ul><ul><li>- methotrexate </li></ul>
  50. 63. <ul><li>Malignant astrocytoma: </li></ul><ul><li>-nitrosoureas are most effective drug </li></ul><ul><li>- commonly used treatment for relapse patient </li></ul><ul><li>Low grade tumour or benign tumour: </li></ul><ul><li>- chemotherapy has limited value </li></ul><ul><li>Medulloblastoma: </li></ul><ul><li>- respond to treatment but value of treatment of patient survival – is unclear. </li></ul><ul><li>Primary germ cell tumour & primary cerebral lymphoma: - chemotherapy has a role. </li></ul>
  51. 64. <ul><li>New approaches: </li></ul><ul><li>Cell targeting: monoclonal antibody is used to carry </li></ul><ul><li>- cytotoxic drug </li></ul><ul><li>- toxins </li></ul><ul><li>- radionuleotide </li></ul><ul><li>to the tumour cells </li></ul><ul><li>Improving access: modifying BBB with mannitol or preliminary binding with liposomes may improve the passage of cytotoxic drug and monoclonal antibodies to tumour tissue. </li></ul><ul><li>Intracarotid injection: of slow releasing biodegredable polymers of nitrosoureas in patient with </li></ul><ul><li>- malignant glioma </li></ul><ul><li>Invitro chemosentitivity testing: utilizes cultured tumour cells from biopsy meterial. </li></ul>