Hypofractionation in breast cancer

Yadav BS, Sharma SC Assistant Professor, Dept. of Radiotherapy, PGIMER, Chandigarh

Introduction

• • Breast cancer is as sensitive to fraction size as the normal tissues of the breast and underlying rib cage Hypofractionated radiotherapy is an established treatment in patients with breast cancer.

Aim

To see impact of hypofractionated radiotherapy in breast cancer patients. • Cosmetic outcome • Locoregional recurrence • Disease free survival • Overall survival

Materials and methods

Duration: Analysis: Patient No: Mean age: Variables: Jan 1987 to Dec 2007 Retrospective 2756 49 years Age, menopausal status, tumour stage, histology, grade, DRP, ECE, LVI, ER/PR & HER-2 status

Treatment: Median FU

: Radiotherapy, chemotherapy & hormones 64 months

Age Menopausal status

≥40yr 82% <40yr 18%

54 52 50 48 46 44 42

46% Pre 54% Post

Surgery

• • TM+AC: BCS: 2139(83.5) 420(16.5) • Median No. of nodes: 10:11

Pathological

Characteristics N(%) Tumor stage

T1T2 T3T4

Histology

IDC ILC Others

Grade

I&II III Unknown

DRP

Involved Free 1361(53) 1218(47) 2328(90.5) 90(3.5) 151(6) 2022(79) 446(17) 101(4) 291(11) 2278(89)

Nodal status

50 45 40 35 10 5 0 30 25 20 15

44%

N0

39%

N1 & 2

7%

N3

Characteristics LVI

Yes No

ECE

Present Absent

ER

Positive Negative Unknown

PR

Positive Negative Unknown

HER-2

Positive Negative Unknown

N(%)

522(20) 2247(80) 175(7) 2394(93) 1220(47) 414(16) 935(37) 1044(40) 870(33) 955(27) 256(10) 993(38) 1330(52)

Radiotherapy PMRT Intact Breast Machine: Fields:

CW SCF 35Gy/15#/3wks 40Gy/15#/3wks 40Gy/16#/3wks Cobalt/Linac Tangential SCF

Systemic Treatment

Chemotherapy N(%) Yes No Hormones Yes No 1077(42) 1492(58) 1837(70) 722(30)

Results

35 30 25 20 15 10 5 0

RT 7,7 LRR No RT 33

LRR

RT No RT 46

BCS

7 30

Mast

8

Distant metastases

22 38 RT No RT

Cosmesis

45% 40% 35% 30% 25% 20% 15% 10% 5% 0%

38% 42% Excellent Good 17% Fair 3% Bad

LRRFS

93% 70% RT p<0.001

No RT

Overall survival

86% 76% p<0.001

RT No RT

Dose & fractionation

16 14 4 2 0 12 10 8 6

50Gy 40Gy 35Gy

UK Chd

Conclusion

• • Hypofractionation reduces treatment time to half while maintaining cosmesis and control rates equal to conventional fractionation. It will help the radiation centers worldwide to meet the growing need for radiation in breast cancer, particularly in developing countries where resources are limited.