Radiotherapy & Chemotherapy in Gynecology - PowerPoint Presentation

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Radiotherapy & Chemotherapy in Gynecology 

Dr.Thabat

J. Al-

Maiahy

MBChB,DOG,CABOG

Radiotherapy

EXTERNAL RADIATION THERAPYIndicated when an area to be irradiated is large, e.g

cx cancer

The basic tent of radiation therapy is to maximize the tumor damage while minimizing the

the

damage to the surrounding normal tissues ,the area determined by means of modern imaging modality: CT , MRI, PET…..

BRACHYTHERAPYMeans treatment at a short distance. During this therapy sealed or unsealed radioisotopes are inserted or instilled in to the cancer or its immediate vicinity.Indicated

only when the cancer

size

is small ,less than 3-4cm in greatest dimension BT is typically practiced after external radiation therapy has decreased the tumor size

Intra

cavitory

, interstitial, intra peritoneal brachytherapy:

During intra

cavitory

BT ,the applicators holding the sealed sources, such as cesium are inserted in to a body cavity such as the uterus

, interstitial

BT requires the placement of catheters or needles directly in to the cancer and surrounding tissues.

The typical

sources

used in interstitial brachytherapy is

irridum

unsealed sources, such as phosphorus and gold are available as solutions for instillation in to peritoneal cavities

NORMAL TISSUE RESPONSE TO IONIZING RADIAATION

In general radiation therapy is less well tolerated when:1-the size of

tissues irradiated is large.

2-

dose is high

3- the dose per fraction is

large

4-the patient age is advanced

Factors that can exacerbated the radiation damage to normal tissue these include Previous surgery

Concurrent chemotherapy

Infection

Diabetes mellitus

HT

Inflamatory

condition (

crohn

disease & ulcerative colitis)

What are the effect of(RT)on tissues?

 1-epithelium and parenchymaAtrophy is the most consistent sequel (include lining epithelium skin GIT……..) necrosis ,ulceration ,capillary the most sensitive vessels ,rupture wall ,large arteries (atheroma-like calcification)may develop. 

2-skin

erythema,

dry

desqumation

, necrosis ,hyper and hypopigmentation can be seen ,the skin remains atrophied, thin and

dry.

3-vagina

commonly leads to acute vaginal

mucositis

, mucosal ulceration is rare. delayed reaction ,vaginal shortening ,atrophic vaginitis ,formation of

synechiae

or

telangictasia

,these avoided ,by use the dilators vaginal intercourse resumed following treatment

Rectovaginal

fistula can develop after advanced stage cancer.

4-ovary and pregnancy outcomesIt s effect depend on age and dose of IR( above 40 years sterility)Among female childhood cancer survivors who received abd irradiation ,higher spontaous abortion ,lower first born birth weight.

5-bladder

acute cystitis 2-3 weeks of start

treatment,

frequency ,pain develop commonly hematuria is rare

Major chronic complications bladder contracture ,

haematuria

6-

small bowel

vulnerable to IR acute early damage acute

malabsorption

syndrome (

nausea

,

vomiting,diarrhea,pain

) later chronic nature of radiation induced enteritis

7

-kidney

acut

radiation

nephropathy typically 6-12 month after IR expose ,chronic nephropathy may occur after special cases.

Does radiation induced carcinogenesis?

Development of a secondary, radiation-induced cancer depends on the age at exposure, dose of IR, and susceptibility of specific tissue types to radiation-induced carcinogenesisHigh: breast ,BMModerate: ovary,

bladder

Low :

cx, uterus,

rectum

CHEMOTHERAPY

Each tumor type has its own characteristics ,which explains why the same chemotherapy regimen is not equally effective for the whole spectrum of gynaecology cancers?

TYPESPrimary for patients with an advanced malignancy when no feasible alternative treatment existsAdjuvant

describes systemic

treatment

after a primary tumor has been controlled but risk of recurrence remains high

3.Neoadjuvant

refers to drug treatment directed at an advanced cancer to decrease preoperatively the extent or morbidity of

asubsequent

surgical resection

Salvage

applied to recurrent

tumor that is

refreactory

to

initial treatment

Combination therapyIn principle combination ofchemotherapy provides maximum cell kill with minimal or

tolerable adverse patient side effect

Drugs are selected based on

their proven efficacy as single agents, different mechanisms of action ,and minimally overlapping toxicities

Multiple drugs with different mechanism of action tends to

minimize the emergence of drug resistance

Drugs used in any combination should have clinical data indicating that their effects will be synergistic or at least additive in evaluating response to chemotherapy

HOW TO EVALUAT RESPONSE TO CHEMOTHERAPY?

Partial response a decrease of 50%or more in the product of all measurable lesion lasting for at least one month with out the development of new lesionsStable disease A decrease of <50 percent or an increase of <25 percent in the product of the diameters of all measurable disease

Progression

an increase of 25% or more of measurable lesion as described above or the identification of new lesions

Complete

response

resolution of all disease lasting for at least one month

CHEMOTHERAPUTIC DRUGSIn gynecological oncology diverse compounds that have demonstrated activity includesAntimetabolites ,alkalating agents ,anti tumor antibiotic ,plant

alkaloids,taxans

,hormonal agents ,biologic therapies ,vaccines.

These drugs may be used as single agent or in combination regimens

BIOLOGICAL THERAPYDesigned to more accurately target specific tumors while avoiding much of the toxicity seen inconventional chemotherapy, refered to as immunotherapy or biological response

modifer

therapy

May

enhance the

chemosensitivity

of malignant cell to

treatmrnt

or may

use the body immune system to attack the cancer

VACCINESTherapeutic cancer vaccines are designed to induce cellular component of the immune system to recognize and attack tumorsBone toxicity ,GIT toxicity

Thank you