oncology imaging principal imaging modalities

Oncology ImagingOncology ImagingOncology ImagingOncology Imaging

Principal Imaging ModalitiesPrincipal Imaging Modalities

Plain films (images) Ultrasound (US) Computed Tomography (CT) Magnetic Resonance Imaging

(MRI) Nuclear Medicine

Contrast mediaContrast media

Barium sulphate Organic iodine preparations Ultrasound contrast agents Magnetic Resonance Imaging cont

rast agents.＊ Contrast media may have allergic

reactions.

Reactions related to Iodinated Reactions related to Iodinated contrast mediacontrast media

Minor reactions: nausea, vomiting, urticarial rash, headache.

Intermediate reactions: hypotension, bronchospasm

Major reactions: convulsions, pulmonary oedema, cardiac arrhyt

hmias, cardiac arrest.

Radiation Protection (Radiation Protection (11) )

Although ionizing radiation is deemed to be potentially hazardous, the risks should be weighed in context of benefits to the patient.

Radiation Protection (2)Radiation Protection (2)

Clear requests with relevant clinical details.

Discussion of complex cases with radiologists.

Radiation Protection (Radiation Protection (33))

Ultrasound

}Lack of ionizing radiation

M R I

Digital RadiographyDigital Radiography

The principal advantages of digital radiography are: significant reduction in radiation e

xposure; digital enhancement ensures all i

mages are of an adequate quality; transfer of images out of the radiol

ogy department to other sites;

Digital RadiographyDigital Radiography

elimination of storage problems associated with conventional films:

no missing films; rapid retrieval of previous

images and reports for comparison;

ease of availability of examinations to clinicians.

UltrasoundUltrasound

USES Brain: Imaging the neonatal brain. Thorax: Confirms pleural effusions

and pleural masses. Abdomen: Visualizes liver, gallbladder, pancreas, kidneys, etc. Pelvis: Useful for monitoring

pregnancy, uterus and ovaries. Peripheral: Assesses thyroid, testes and soft-tissue lesions.


Advantages

Relatively low cost of equipment.

Non-ionizing radiation and safe.

Scanning can be performed in any plane.

Can be repeated frequently, for example pregnancy follow up.


Advantages

Detection of blood flow, cardiac and fetal movement.

Portable equipment can be taken to the

bedside for ill patients.

Aids biopsy and drainage procedures.


Disadvantages Operator dependent. Inability of sound to cross an

interface with either gas or bone causes unsatisfactory visualization of underlying structures.

Scattering of sound through fat produces poor images in obesity.

Computed TomographyComputed Tomography

USES Any region of the body can be scanned;

brain, neck, abdomen, pelvis and limbs. Staging primary tumours such as colon

and lung for secondary spread, to determine operability or a baseline for chemotherapy.

Radiotherapy planning. Exact anatomical detail when ultrasou

nd is not successful.


Advantages Good contrast resolution. Precise anatomical detail. Rapid examination technique, so

valuable for ill patients. In contrast to ultrasound,

diagnostic images are obtained in obese patients as fat separates the abdominal organs.


Disadvantages High cost of equipment and scan. Bone artefacts in brain scanning, espe

cially the posterior fossa, degrade images.

Scanning mostly restricted to the transverse plane, although reconstructed images can be obtained in other planes.

High dose of ionizing radiation for each examination.

Magnetic Resonance ImagingMagnetic Resonance Imaging

USES Central nervous system (CNS):

technique of choice for brain and spinal imaging.

Musculoskeletal: accurate imaging of joints, tendons, ligaments and muscular abnormalities.

Cardiac: imaging with gating techniques related to the cardiac cycle enables the diagnosis of many cardiac conditions.


USES Thorax: assessment of vascular struct

ures in the mediastinum. Abdomen: abdominal organs are well

visualized, surrounded by high signal from surrounding fat.

Pelvis: staging of prostate, bladder and pelvic neoplasms.


Advantages

Can image in any plane-axial, sagittal or coronal. Non-ionizing and hence believed to be s

afe to use. No bony artefacts due to lack of signal fr

om bone.


Advantages

Excellent anatomical detail especially of soft

tissues. Visualizes blood vessels without

contrast: magnetic resonance angiography

(MRA). Intravenous contrast utilized much less frequently than CT.


Disadvantages High operating costs. Poor images of lung fields. Inability to show calcification

with accuracy.


Disadvantages Fresh blood in recent haemorrhag

e not as well visualized as by CT. MRI more difficult to tolerate with

examination times longer than CT. Contraindicated in patients with p

acemakers, metallic foreign bodies in the eye and arterial aneurysmal clips (may be forced out of position by the strong magnetic field).

Respiratory TractRespiratory Tract

Modalities for Respiratory Tract Modalities for Respiratory Tract InvestigationsInvestigations

Plain films (images)

Computed tomography (CT)

Ultrasound (US)

Isotopes

Pulmonary angiography

Magnetic resonance imaging (MRI)

CT for Respiratory tractCT for Respiratory tract

Excellent detail for localizing and staging mediastinal masses and bronchial neoplasms.

Assesses hilar areas to identify lymphadenopathy, and to differentiate from prominent pulmonary arteries.

Visualizes accurately pleural masses, plaques and fluid associated with asbestos exposure.

US for Respiratory tractUS for Respiratory tract

Presence of the pleural effusions and

loculated fluid.

Biopsy of pleural lesions.

MRI-for respiratory tractMRI-for respiratory tract

Evaluation of mediastinal masses,

aortic dissection and staging bronchial carcinoma.

Evaluation of vascular invasion.

Bronchial carcinomaBronchial carcinoma

A common primary tumour

Histological types:

squamous, small (oat) cell, anaplastic, adenocarcinoma, alveolar cell carcinoma.


Haemoptysis

Respiratory symptoms

Bronchial carcinomaBronchial carcinomaRadiological features Lobulated or spiculated mass but sometim

es with a smooth outline.

Tumours at the lung apex (Pancoast's tumour) can invade the brachial plexus, resulting in shoulder and arm pain with wasting of the hand, or invasion of the sympathetic chain may give rise to Horner's syndrome.


CT/MRI

-Assesses spread.

-Determines operability.

Differential diagnosis of Differential diagnosis of solitary lung masssolitary lung mass

Metastasis: -Breast, kidney, colon,

testicular tumours. Tuberculoma Benign neoplasms

-Bronchial adenoma , hamartoma round pneumonia, hydatid cyst, haematoma , arteriovenous malformation.


Common sites of distant metastases

- Brain - Bone - Adrenals - Liver

Mediastinal massMediastinal mass

Imaging modalities –

Plain film

CT

MRI

Mediastinal massMediastinal mass Anterior mediastinal masses - thyroid , thymus , teratodermoi

d Middle mediastinal masses - lymphoma, metastases, sarcoid or tuberculosis. Posterior mediastinal masses - neurogenic tumours neurofibromas ganglioneuroma

Gastrointestinal Gastrointestinal tract (GI)tract (GI)

Gastrointestinal tract (GI)Gastrointestinal tract (GI)

Imaging modalities

-Plain films (images)-Barium studies-Angiography-Computed tomography

-Ultrasonography -Magnetic resonance imaging

Gastrointestinal tract (GI)Gastrointestinal tract (GI)

CT - to assess for operability by stagin

g oesophageal, gastric and colonic tumours. - to evaluate adjacent infiltration and secondary deposits.

Esophageal CarcinomaEsophageal Carcinoma

Squamous cell type

Distal thirdMale > Female

Predisposing factors - Achalasia - Barrett’s esophagus


Imaging modalities

- Barium

- CT: tumour confinement to the wall or extraluminal spread.

- US: secondary deposits


Radiological features

Polypoidal type: an intraluminal mass protrudes out into the oesophageal lumen causing a filling defect in the barium column.

Infiltrative type: the tumour spreads under the oesophageal mucosa without extending into the lumen, causing narrowing. Later there is mucosal infiltration resulting in ulceration and an irregular outline to the oesophagus.

Gastric CarcinomaGastric Carcinoma

A general decrease in the

incidence of gastric carcinoma.


Clinical Presentations:

Dyspepsia , anorexia, nausea, vomiting,

Body weight loss,

Haematemesis or melaena.


Imaging modalities

- Barium meal

- CT }preoperative evaluation

- US



Barium meal Polypoidal type - soft-tissue mass causin

g a filling defect. Ulcerating type - ulcerating within the margin of the stomach.


Diffuse infiltrating type - diffuse submucosal infiltration ( linitis plastica) small rigid stomach

( leather bottle stomach) { poor distensibility

Local infiltrating type - focal area of mucosal irregularity and narrowi

ng at the site of the tumour.

Colonic carcinomaColonic carcinoma

Commonest malignancy of GI tract.

Usually adenocarcinoma


Imaging modalities

- Plain films. - Barium - Ultrasound - CT/MRI colonoscopy staging



Annular carcinoma - irregular luminal narrowing , apple-core deformity. Polypoidal mass - intraluminal filling defect.


Complications

- Obstruction - Perforation - Fistula formation


Differential diagnosis of colonic narrowing

- Diverticular disease - Crohn's disease - Ulcerative colitis


Differential diagnosis of colonic narrowing

- Extrinsic: inflammatory / neoplastic infiltration. - Radiotherapy - Tuberculosis. - Ischaemia.

Hepatocellular carcinHepatocellular carcinomaoma

Hepatocellular carcinomaHepatocellular carcinoma

Common tumour in Chinese.

Chronic hepatitis B carriers.

Fungal aflatoxin food contamination.


Clinical Presentation

- upper abdominal pain - weight loss - fever


Three principal types

- Multinodular - Infiltrative - Solitary mass



- CT/MRI precontrast : low/isodense mass arterial phase : hypervascular

mass delayed phase : wash-out mass


The tumor should be assessed for invasion of the vascular system and the biliary system.


About 20% ( ? ) are suitable

for liver resection.

Liver MetastasesLiver Metastases

The liver is the most common organ of secondary deposits.

The primary sites are : colon, stomach, pancreas, breast and lung.

Pancreatic carcinomaPancreatic carcinoma

The most frequent pathological type arises from the pancreatic duct epithelium (Adenocarcino

ma).


Clinical Presentation - Abdominal pain - Weight loss, anorexia. - Obstructive jaundice. - Malabsorption, diarrhoea. - Diabetes.


Clinical symptoms usually occur late and at the time of presentation there is often local invasion of blood vessels or bowel.


Radiological features US/CT

- focal pancreatic enlargement with a hypoechoic /hypodense mass. - pancreatic and bile duct dilatation - distended gallbladder.


MRI –

Reduced signal from pancreas on T l sequence.

The Urinary TractThe Urinary Tract


Imaging modalities

- KUB- Intravenous urography (IVU)

- Retrograde pyelography - Antegrade pyelography


Imaging modalities

- Percutaneous nephrostomy - Micturating cystogram - Urethrography


Imaging modalities

- Ultrasound- Computed Tomography- Arteriography

Renal carcinomaRenal carcinoma

Radiological features Plain film – Renal mass (calcifications) IVP – Renal Mass, pelvicalyceal distortion and irregularity US – Solid mass with increase vascularity CT/MRI – Useful for staging, perinephric tissue invasion, venous invasion, lymph node metastasis

Bladder carcinomaBladder carcinoma

Radiological features IVP – Filling defect in the bladder Irregular mucosa CT/MRI – Useful for staging Intramural /extramural spread , local invasion , lymph node metastasis

Testicular tumourTesticular tumour

US – extremely effective in evaluation of well defined low echogenicity mass

MR imaging of clinical stage I anMR imaging of clinical stage I and IIa cervical carcinoma: a reapd IIa cervical carcinoma: a reap

praisal of efficacy and pitfallspraisal of efficacy and pitfalls Parametrial invasion: 96.7%Parametrial invasion: 96.7% Vaginal invasion: 87%Vaginal invasion: 87% LAP: 87%LAP: 87% Staging accuracyStaging accuracy MRI: 83.8%, Clinical staging: 61.3%MRI: 83.8%, Clinical staging: 61.3% stage IIa vs. stage IIa vs. stage IIB stage IIB MRI: 96.7%, Clinical staging: 80.6%MRI: 96.7%, Clinical staging: 80.6%

Europ Radiol 2001Europ Radiol 2001

Skeletal system Skeletal system

Imaging modalities Plain films (images) – still remain th

e mainstay of investigation Isotopes – Tc 99m phosphate compo

unds US/CT/MR – for tumour vascularity,

infiltration of surrounding tissure relationship to nerves and vessels

OsteosarcomaOsteosarcoma

Plain films (images)Radiological features

Irregular medullary destruction Periosteal reaction Cortical destruction Soft tissure mass New bone formation

Bone metastasesBone metastases

Plain films (images)Radiological features

- Lytic deposits : poor definition of margins,

pathological fracture - Sclerotic deposits : an area of ill- defined increased density

Bone metastasesBone metastases

- Most frequent primary are Breast

Prostate Lung Kidney Thyroid Adrenal gland

Multiple myelomaMultiple myeloma

Radiological featuresPlain films (images)- Generalized osteoporosis- Compression fracture of vertebral

bodies- Scattered ‘pounch-out’ lytic lesions

with well-defined margins- Bone expansion with soft-tissue masses

Choose the most Choose the most appropriate appropriate

imaging modality is the key imaging modality is the key for accurate effective for accurate effective diagnosis and treatment.diagnosis and treatment.

oncology imaging principal imaging modalities

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