radiation for cervix cancer
DESCRIPTION
The role of radiation in treating cervix cancerTRANSCRIPT
Robert Miller MDwww.aboutcancer.com
Cervix Cancer the Role of Radiation
Most common gynecologic cancers in women in 2012
Site Number
Breast 232,340
Uterus 49,560
Ovary 22,240
Cervix 12,340
Vulva 4,700
Median age at diagnosis for cancer of the cervix uteri was 49 years of age (uterus 61, ovary 63, vulva 68)
Lifetime risk is 0.66% or 1 in 151 of women born today will be diagnosed with cancer of the cervix
Stage Distribution 5 Year Survival
Local (confined site)
47% 91%
Regional (into nodes)
36% 57%
Distant (metastases)
12% 16%
• Avoidance of Human Papillomavirus Infection (abstinence, or condoms (lower risk by 60%)
• HPV16/18 vaccination will lower the risk by 92%
• Screening (pap smear) will lower incidence and mortality by 80%
• Smoking cessation (smoking cigarettes increases the risk in HPV+ women by 2 to 3 times)
Importance of screening because of disease progression
uterus
cervix
vagina
Spreading cancer
parametrium
Intovagina
Early Stage IA more advanced IA stage II
Work up or evaluation of a patient with cervix cancer before deciding on therapy
biopsy
Pathology Report• Invasive cancer or just dysplasia or in situ• Histology or type of cancer
• Squamous cancer (69%)• Adenocarcinoma (25%)
• Depth of invasion and lateral spread
Stages of Cervix Cancer
uterus
Cervix cancer
Stage I = confined to the cervix
IA = too small to see (found only on microscope)
IA1 = no deeper than 3mm or lateral than 7mm
IA2 = 3 to 5mm deep and lateral up to 7mm
IB = visible or bigger than a IA2
IB1 = up to 4cm IB2 = bigger than 4cm
Stages of Cervix Cancer
Stage II = beyond the cervix
IIA = onto the upper vagina
IIA1 = up to 4cm
IIA2 = over 4cm
IIB = parametrial invasion
Stages of Cervix Cancer
Stages of Cervix Cancer
Stage IIIA = lower third vaginaStage IIIB = side wall or nodes +
Stage IVA = into bladder or rectumStage IVB = distant metastases
Cross section anatomy of the female pelvis
bladder
rectumcervix
Cross section anatomy of the female pelvis
rectum
vagina
rectum
PET Scan = Cervix Cancer
Cancer cells use more glucose or sugar and so “light up” on a PET scan which uses radioactive glucose
Lymph Nodesspread from the cervix
Frequency of lymph node metastases in cervical carcinoma.
Cervix cancer that has spread to para-aortic and pelvic nodes as seen on PET scan
Internal view (cross section) from PET
PET = Stage IIIB Cervix Cancer
Stage 5 Year Survival
IB 80%
IIA 63%
IIB 58%
III 30%
IVA 16%
Cervix Cancer Survival by Stage
Stage Survival SurvivalIA IA1 (97.5%) IA2 (94.8%)
IB IB1 (89.1%) IB2 (75.7%)
II IIA (73.4%) IIB (65.8%)
III IIIA (39.7%) IIIB (41.5%)
IV IVA (22%) IVB (9.3%)
Cervix Cancer Survival
NCCN.org
Treatment of cervix cancer
• Early stages: surgery (hysterectomy) or radiation
• More advanced cases: radiation +/- chemotherapy (cisplatin) then possibly surgery
Early Stages: Surgery or Radiation
More Advanced Stages: Radiation or Surgery
Indications for post-operative radiation and or chemotherapy based on pathology report after surgery
• Positive lymph node spread• Positive surgical margins• Invasion into the parametrium• Other high risk features:
• Large primary tumor• Deep stromal invasion• Lymphovascular invasion
Advanced Stages: Radiation plus Chemotherapy
5 Trials Demonstrating Improved Survival with Chemo-Radiation compared to
Radiation Alone
External Beam Radiation
Radioactive sourceApplicators
Internal Radiation
CT scan is obtained at the time of simulation
CT images are then imported into the treatment planning computer
In the simulation and treatment planning process the CT and PET scan images are used to create a “target” for the radiation and a computer plan is generated
During the treatment lasers are used to line up the beam and the patient receives the radiation treatment
External beam radiation is usually 5 to10 minutes, Monday though Friday, 5 days a week for 5 to 30 treatments
Normal structures identified on CT scans that can be affected by radiation and cause side effects
Normal Structures Identified on MRI
uterusuteruscervix cervix
vagina vagina
rectum rectum
bladderparametrium
Computer generated targets for IMRT Radiation for advanced cervix cancer to treat pelvis plus para-aortic lymph nodes
Combine a CT scan and linear accelerator to ultimate in targeting (IGRT) and ultimate in delivery (dynamic, helical IMRT) ability to daily adjust the beam (ART or adaptive radiotherapy)
Radiation for cervix cancers
• External beam irradiation (daily for 5 weeks) sometimes combined with chemotherapy (e.g. cisplatin)
• Low dose radiation (LDR) Internal radiation (radium or cesium implants, in hospital for 2-3 days
• High dose rate radiation (HDR) with Nucletron (Iridium) once a week for 3-5 weeks as an outpatient
Radiation Dose Techniques
• External beam 45Gy (40-50Gy) plus possible sidewall boost of 10-15Gy
• Brachytherapy: Point A total dose of 30-40Gy (LDR or 6Gy X 5 with HDR) to 80- 85Gy total dose
Internal radiation devices or brachytherapy
Internal radiation devicesTandem goes into the uterus
Ovoids go into the corners (fornices) next to the cervix
Internal Radiation Devices
HDR = high dose rate machine that can run radiation through a tube that reaches the patient through vaginal applicators
HDR Cervix Applicators
Internal radiation devices
Procedure can be performed in hospital and the patient stays over night using a Cesium isotope applicator or the procedure can be done as an outpatient with a faster technique (called high dose rate or HDR) using an Iridium isotope source (Iridium 192 with half life of 74 days)
Vaginal cylinder is inserted into the vagina, the radiation tube or wire stays inside the tube and doesn’t touch the patient’s skin
A Wire or Tube connects the vaginal or cervical applicators to the machine that holds the radioactive (Iridium) source
The woman lays on the radiation table and the treatment usually takes about 5 minutes and then the applicator is removed
Radiation Fields and Side Effects
Pelvic field
Para-aortic
Node field
Side Effects of Radiation are Related to Organs that are near the Cancer
Side Effects of Pelvic Radiation
ovary
Side Effects of Pelvic Radiation
Radiation may hit the bowel causing some more bowel frequency, cramps, diarrhea and fatigue
Radiation fields
Side Effects of Pelvic Radiation
Radiation fields
Radiation may hit the bladder and rectum causing urinary burning or frequency and rectal irritation as well as vaginal irritation
Patients may benefit from Imodium, cranberry juice, skin creams and rectal ointments
Long Term Side Effects of Pelvic Radiation
• Chronic bowel irritation (looseness or bleeding)• Chronic bladder irritation (more frequency or
burning)• Sexual dysfunction (more vaginal dryness or
fibrosis)• Ovarian dysfunction (normal pelvic radiation doses
to the ovaries will cause menopause)• Osteitis of the bone (more brittle bones)
Robert Miller MDwww.aboutcancer.com
Cervix Cancer the Role of Radiation