Radiotherapy in Carcinoma of the Breast
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Transcript of Radiotherapy in Carcinoma of the Breast
Radiotherapy in Carcinoma of the Breast
Patrick S Swift, MDDirector, Radiation Oncology
Alta Bates Comprehensive Cancer CenterBerkeley, CA
Breast Conserving Therapy BCT
70-80% of patients with stage I or II disease are candidates for BCT
6 major randomized trials comparing mastectomy to BCT No difference in DFS No difference in OS
Distant Failure
Trial # Time pt. Mast. BCT
WHO 1972-79 179 22 yrs 24% 23%
Milan I 1973-80 701 20 51% 54%
NSABP06 1976-84 1406 20 33% 40%
US NCI 1979-89 279 20 34% 39%
EORTC 10801
1980-86 903 10 34% 30%
Denmark 82TM
1983-89 859 6 32% 34%
Overall Survival
Trial # Time pt. Mast. BCT
WHO 1972-79 179 22 yrs 41% 42%
Milan I 1973-80 701 20 47% 46%
NSABP06 1976-84 1406 20 58% 53%
US NCI 1979-89 279 20 66% 65%
EORTC 10801
1980-86 903 10 79% 82%
Denmark 82TM
1983-89 859 6 67% 67%
Absolute Contraindications to BCT
Repeatedly positive marginsMulticentric disease ( >2 quadrants)Diffuse malignant calcifications on
mammogramPrior RT to breastPregnancy
Relative Contraindications to BCT
History of sclerodermaLarge tumor in small breast
Cosmetically undesirable
NOT contraindications to BCT
AgeSkin or nipple retractionHistology other than IDCExtensive intraductal component
As long as margins are clearPositive nodesLocation of primary in breastPositive family history
Positive Margins after Lumpectomy
Single most important predictor of local failure in BCT
Consider re-excision to get negative margins
Focal positivity - may be okay Especially if chemo or HT given
Extensive positivity - re-excise!
Extensive Intraductal Component (EIC)
Intraductal component a prominent part of the main tumor
Intraductal carcinoma extends BEYOND the infiltrating margin of the mass
Of uncertain significance if margins are clearly negative
Treatment by Stage
DCISDuctal Carcinoma in Situ
MRM is acceptable no node dissection
BCT is an acceptable approach if: Lesion is small (< 3 cm) Margins must be negative
preferably > 10 mm in all dimensions Nuclear grade is low to intermediate Adjuvant radiotherapy can be delivered
S alone can be considered if margins >10 mm controversial
NSABP-17
814 pts. with DCIS, negative marginsRandomized to RT v no RT
50 Gy to entire breast, no boostAt 12 years, local failure rates
31.7% for no RT 15.7% for RT
Only comedo necrosis was a significant factor predicting for local failure
EORTC 10853
500 pts with DCIS, clear marginsRandomized to 50 Gy whole breast or
no RTAt 4.25 years, local failure
16% no RT 9% with RT (p=0.005)
UKCCCR DCIS Working Group
1030 pts with DCIS, clear marginsS alone S + TamS + RTS + RT + TamAt 4.4.years, local failure
14% in no RT 6% in RT arm S + Tam intermediate
Radiation TechniqueDCIS
Opposed tangential fieldsBreast onlyNo boost1.8-2.0 Gy daily to 50 Gy2.65 Gy daily to 40 Gy
Van Nuys Prognostic Index
Scores of 3-4 - 98% local control without RTScores of 5-7 - 32% failed without RT, 16% with RTScores of 8-9 - 100% failure without RT, 60% with RT
Radiation TechniqueT1-2 N0
Opposed tangential fieldsBreast onlyBoost optional50 Gy in 25-28 fractions42.5 Gy in 16 fractions (Canadian)
ASTRO 2008 Plenary
42.5 Gy in 16 fractions v. 50 Gy in 25 fractions
ASTRO 2008 Plenary
Canadian Trial 1993-1996N= 1234 womenMedian followup - 12 yearsLocal recurrence at 10 years - 6%Excellent cosmesis at 10 yrs - 70%No difference between 16 and 25
fractions
If getting chemotherapy…
Radiation is usually withheld until after the systemic therapy is complete
Delay of up to 4-6 months from surgery generally not considered a problem
Possible problem with inflammatory cancer or other locally aggressive cancers
Hypofractionated schemes may allow for early RT while waiting for Oncotype
Surgery alone without RT?
Meta-analysis results Lancet. 2005 Dec 17, vol. 366(9503):2087-106 “Effects of radiotherapy and of differences in the
extent of surgery for early breast cancer on local recurrence and 15-year survival: an overview of the randomised trials.”
An average of 75% reduction in local failure rates with the addition of RT, in even the lowest risk groups.
A survival benefit was seen in the meta-analysis
Surgery alone without RT?
One possible subset may benefitPatients > 70 years of age
with small ER+ tumors who will get tamoxifen
No survival benefit with RT
Radiation TechniqueT3-4 (after neoadjuvant chemo)
Opposed tangential fieldsBoost
10 Gy for neg margins 18 Gy for positive or close margins
50 Gy in 25-28 fractions
Nodal Irradiation
N0 - no role for axillary RTN+
1-3 nodes, “adequate sampling” - no RT > 4 nodes, RT to SCLV and axilla
IM Nodal RT > 4 axillary nodes positive Medial T3 tumors with any nodes positive
axillaAwaiting results of two large trials (France and
EORTC)
Full SCLV Field
IM Nodal Radiation Technique
Post-mastectomy RT
Indications T3 lesions with any positive nodes Smaller lesions with > 3 nodes T4 lesions Pectoralis fascia involvement
Technique Tangential beams for the chest wall Axillary/SCLV coverage IM node coverage for medial lesions or > 3 nodes
positive
Post-MRM RT Trials(all with chemo and modern RT)
Local failure
Overall Survival
Danish 82b 1708 RT 9% 54%
No RT 32% 45%
Vancouver 318 RT 13% 54%
No RT 33% 46%
Danish 82c 1375 RT 8% 45%
No RT 35% 36%
RT Complications
Lymphedema After full axillary dissection + RT - 37% Level I/II dissection + RT - 7%
Rib fracture - 1.8%Pneumonitis - 1-5%Cardiac toxicity - avoidableRadiation-induced sarcoma
0.78% at 30 yrs.
Reducing Risk
Respiratory Gating
IM nodal techniques
IMRT
Partial Breast Irradiation
RTOG / NSABP Trial comparing Standard whole breast RT 3D conformal technique Mammosite Interstitial Implant technique
5 days, twice daily radiationOutcome results pending