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