Radiotherapy of cervical cancer

RADIOTHERAPY OF CERVICAL CANCER

RAKSHITH AVB

Modalities of Radiotherapy

• BRACHYTHERAPY

• TELETHERAPY

BRACHYTHERAPY

• Internal radiation treatment achieved by implanting radioactive material directly into the tumor or very close to it.

• Sometimes called internal radiation therapy.

• Prefix “brachy” – from Greek for “short range”

TYPES OF BRACHYTHERAPY

1)Intracavitary irradiation using radioactive

sources that are placed in body cavities in close

proximity to the tumor and

2) Interstitial brachytherapy using radioactive

seeds implanted directly into the tumor

volume.

WHY BRACHYTHERAPY

• Delivering the high dose of radiation to the

tumor

• Sparing of the surrounding normal tissues

• Delivered in a short period of time

– Tumor repopulation

• Limited to localized tumors

TELETHERAPY

• Teletherapy or External Beam Radiation

Therapy" involves delivery of therapeutic

radiation from a source

• that is placed away

• from the body.

INITIAL TREATMENT

2 Components of CA Cervix

• Central: Growth in the cervix which is best treated by Brachytherapy

• Peripheral: Growth in parametrium & lymph node metastasis which is best controlled by Teletherapy

PRINCIPLES OF MANAGEMENT

• Patients with Stage I - IIA can be managed by surgery alone.

• Patients in Stage IIB - IV CHEMORADIATION– Brachytherapy followed by Teletherapy

4 –6 weeks later.–Chemotherapy

PRINCIPLES OF MANAGEMENT

• The relative proportion of Teletherapy

increases with bulk & stage of tumor.

• Usually Brachytherapy followed by

teletherapy 4 to 6 weeks later.

INDICATIONS FOR EBRT PRIOR TO BRACHYTHERAPY

• Bulky tumours

• Distorted cervical canal

• Exophytic or bleeding tumors

• Tumors with necrosis or infection

ROLE OF CHEMOTHERAPY

Certain chemotherapeutic drugs such as

Cisplatin, carboplastin , 5 FU etc act as

radiosesitizers & may be given prior to any

form of radiotherapy to enhance the lethal

effect of radiation.

BRACHYTHERAPY

PRERADIATION PREPARATION

• Hb level

• Rectal enema

• Antibiotic cover

TANDEM & OVOID METHOD

• Under GA• Bladder Catheterisation• Cervical dilation• Tandem & ovoids insertion• X ray of pelvis• Afterload technique

ICBT Procedure Overview

PatientPreparation

ApplicatorCheck

Applicatorimplantationand fixation

Imaging TreatmentPlanning

Treatment excution

Patient Preparation• GA• Lithotomy position• Perineal area is

disinfected• Draping• Catheterization

L/e•Applicator set is check for integrity and completeness•Uterine sounding•Correct size of ovoid is selected and mounted onto the ovoidtubes•Dilatation of the cervix•Length of uterus is measured

IU- Tube Insertion• Correct length of IU-

tube is selected and inserted

OVOIDTUBE INSERTION

•Select proper size ovoids•Fixate these to the ovoid tubes•Insert one by one and attach to the fixing mechanism

Applicator packing• Insert gauze packing to

push rectum and bladder away reducing the dose to these organs

• Radio opaque rectal marker inserted

Verification X-ray

X-ray catheters

TECHNIQUES OF BRACHYTHERAPY

• PARIS METHOD

• STOCKHOLM METHOD

• MANCHESTER TECHNIQUE

PARIS METHOD

•Radium is applied continously for

5 days.

•Removed daily for cleaning and

reinserted back.

STOCKHOLM

•Radium is inserted on 3 occasions

•1 week interval between 1st & 2nd

insertion

•2 week interval between 2nd & 3rd

insertion

MANCHESTER

•Two Insertions

•Each insertion lasts for 72hrs

•1 week interval between two

insertions

PRINCIPLES IN BRACHYTHERAPY

• Uniform distribution to avoid Hot & Cold spots

• Two points

Point A - -The point A was described fixed point

2cm lateral to uterine axis and 2 cm above the lateral

fornix.

It represents Anatomical location of Ureter.

Dose not to exceed 8000 rads

PRINCIPLES IN BRACHYTHERAPY

Point B: 5cm from the patient’s midline, at the

same level as point A.

It represents Lateral pelvic wall

Dose not to exceed 500o rads

TELETHERAPY

• SSD(Source to Skin Distance) is 5 to 10 times

the depth of tumour.

• Cobalt-60 and Caesium-137 are commonly

used

• Fractionated radiotherapy is preferred

TELETHERAPY

• Pelvic Radiation: 180 – 200 cGy

• Abdominal Radiation: 100 – 120 cGy

• About 4-5 fractions per week is given

• Total of 25 – 30 fractions is given over 5-6

weeks

COMPLICATIONS

• EARLY COMPLICATIONS Nausea & VomitingBladder irritation: Dysuria & HaematuriaRectal irritation : Tenesmus & diarrhoeaMalaise & IrritabilityPyelonephritis & CystitisSepsis

COMPLICATIONS

• LATE COMPLICATIONS Persistent AnemiaChronic pelvic pain due to fibrosisPyometraUlcers, Strictures & fistulaOsteoporosisOvarian distructions causing menopausal

symptoms

THANK YOU FOR YOUR KIND ATTENTION