Robert Miller MD www.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 Into vagina 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 vagina Stage IIIB = side wall or nodes + Stage IVA = into bladder or rectum Stage IVB = distant metastases
Cross section anatomy of the female pelvis bladder rectum cervix
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 Nodes spread 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 Survival IA 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 Radiatio n Radioactive source Applicators 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 uterus uterus cervix cervix vagina vagina rectum rectum bladder parametrium
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 devices Tandem 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 MD www.aboutcancer.com Cervix Cancer the Role of Radiation