demystified patient populations we treat early breast cancer (incl. dcis): post-lumpectomy locally...
Post on 19-Dec-2015
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Radiation OncologyDemystified
Patient Populations We TreatEarly Breast Cancer (incl. DCIS): post-
lumpectomyLocally Advanced Breast Cancer: post-
MastectomyRecurrent Breast Cancer: chest wall nodulesMetastatic Breast Cancer: bone mets, brain
metsNot LCISNot DCIS if s/p Mastectomy
Think TwiceConnective Tissue Disorder, esp. SclerodermaReally youngReally oldPrevious Radiation Therapy to same siteHistory of Radiation Induced Malignancies
Special CasesReconstructionBilateral (Ca and/or Reconstruction)Comorbidities (such as diabetes, CTDs, CVD,
asthma, lymphedema, port, genetic predisposition to malig)
Tight Arm after Axillary Lymph Node DissectionPrevious Radiation Therapy Tx, or Rad
ExposuresOn systemic treatments that may affect healing
or scarring (antiangiogenic; taxoxifen)On herbals and/or high dose vitamins
TargetsBreastChest WallSupraclavicular/Axillary ApexPartial BreastOperative BedRecurrent Chest Wall NodulesBone MetsBrain Mets
BeamsPhotonsElectrons (boost, intraop)Orthovoltage (TARGIT)Additional Devices
BolusTattoosCustom BraHyperthermiaPort films
Skin CareMoisturizers Antifungal/AntinflammatoryAstringent SoaksMepilexMesh “Bra”Avoid UnderwireMoisturize Irradiated Skin Forever!Follow Up
Simulation
CT-based Treatment Planning
E- Beams
Photon Beams: Single 6 or 18 MV
cobalt
Photon Beams: Parallel Opposed
Photon Beams: 6 vs. 18 MV parallel opposed
Tangents
Dose Cloud Technique (IMRT)
65 cGy 10 cGy15 cGy = 90 cGy+ +
Heart Block
Dynamic Leaves Computerized
Successive Cone Downs on Medial and Lateral Tangential Fields, For example:
Medial Field 1 Medial Field 2 Medial Field 3
CT based Treatment Planning
What might the plan look like if we treated the internal mammary nodes?
Direct AP Photon Field For IMCToo Much Heart
Hockey-stick
OLD DAYS
What might the plan look like if we treated the internal mammary nodes?
10 % e-
e-
0 % e-
10 % Co-60
Co-60
50% Co-60
50% e-
What might the plan look like if we treated the low internal mammary nodes with tangential fields?
3 cm
So what is our target? After BCS Traditionally
Whole breast +/- boost to operative bed & scar
Most agreeAt least: Operative bed + 1 cm
Some would sayOperative bed + 2-3-4 cmWhole breastChest wall
Histologic evidence of tumor in IMC Extended Radical Mastectomy
Author Patients Outer Quadrant Inner Quadrant Any Quadrant
Urban 341 42 % 53 %
Bucalossi 553 29 %
Handley 535 21 % 48 %
Li 635 25% 35%
As high as 53%
What about after Mastectomy? Patterns of Locoregional Failure
No. of PatientsChest Wall ClavicularInternal MammaryAxilla
Univ. Hospital of Cleveland* 209 59% 25% NS 7%
M. D. Anderson* 148 60% 13% 3% 7%
Malinckrodt 129 77% 33% 11% 18%
Univ. of Pennsylvania 128 83% 25% 3% 11%
Institute Jules Bordet 128 77% 25% NS 10%
Mt. Sinai - Miami 124 77% 11% 8% 21%
ECOG * 70 53% 24% NS 11%
DBCG 214 64% 17% NS 34%
*Details about multiple sites not provided 53 - 83%
0 – 11%
Risks: IMC Failure An IMC failure is difficult
to salvage.Reirradiation of this area
would be morbid.There is no proven
survival advantage to treating the IMC region
In select patients we do treat the upper IMC region
Luckily, it is clear that the IMC region can be safely excluded for patients with DCIS, so we can even better spare the heart and lung in those patients.
Risks: Local RecurrenceSome patients who wished
for breast conservation will require a mastectomy.
Reirradiation can cause tissue and chest wall necrosis and severe fibrosis. We treat with 400 cGy x 8 with hyperthermia.
Without reirradiation, the salvage surgery will need to be a larger procedure (wide margins) and the patient may yet fail again.
It’s not a pretty picture.
Chest Wall FailureThis is not where
we want to be.This is not
salvagable.
Important Questions . . . Pandora’s Box
Physician philosophy on IMN treatment Risks Benefits
Physician philosophy on partial breast irradiation Will leave some breast out of field to spare heart? Use of mammosite or other brachytherapy device?
Physician philosophy on margin status
Caveat: No national consensus on above, and the actual treatment plan greatly depends on the patient’s anatomy in treatment position institutional standard of care Clinical judgment informed patient choice
TARGIT
Hyperthermia
Mammosite
IMRT Breast