Accelerated hypofractionated adjuvant whole breast radiation with simultaneous integrated boost using volumetric modulated arc therapy for early breast cancer: A phase I/II dosimetric and clinical feasibility study from a tertiary cancer care centre of India.
BACKGROUND
Hypofractionation has become standard of care after Breast Conserving Therapy (BCT) in many European and few others western countries. Though still debatable, tumor cavity boost is routinely practised in our centre. Hypofractionation is not yet the current standard of practice in Asian countries. Employing hypofractionation and simultaneous integrated boost to lumpectomy cavity with conformal technique is not the current practice in this region. Hence the study was performed to see whether accelerated hypofractionation and simultaneous boost can be combined using volumetric modulated arc therapy (VMAT) in treating early breast cancer (EBC) patients.


METHODS
Female patients with EBC treated by whole breast radiation and boost were treated simultaneously to a dose of 40.5Gy and 48Gy in fifteen fractions over three weeks to entire breast and tumor cavity respectively with VMAT. Dosimetry including target coverage, OAR (organ at risk) sparing and acute radiation toxicity were evaluated.


RESULTS
Ten consecutive patients were treated. Planning target volume (PTV) coverage and OAR sparing were mostly satisfactory. Mean volume of PTVWBand PTVBoostwere 786.18cm3and 228.9cm3respectively. Mean Dmeanto PTVWBand PTVBOOSTwere 41.9Gy and 49.1Gy respectively. Dmax to PTVWBand PTVBOOSTwere 127.56% and 110.67% respectively. Ipsilateral lung mean dose and V20 were 13.92Gy and 21.53% respectively. V40 and V25 of heart were 0.17% and 2.25% respectively. All patients are disease free after a median follow up of two years. Most acute toxicities were Grade1. Only two patients out of ten developed Grade 2 skin reaction during radiation. Early cosmesis using Harvard cosmesis scale is good to excellent.


CONCLUSIONS
Accelerated hypofractionated RT using SIB-VMAT is a clinically feasible technique with acceptable initial result. Initial results are encouraging.


CONCLUSIONS
Simultaneous integrated boost with accelerated hypofractionated whole breast radiotherapy using Volumetric Modulated Arc Therapy is a novel approach. Patient selection and technical considerations are of paramount importance. The present study describes successful implementation of this approach.
Department of Radiation Oncology, All India Institute of Medical Sciences, New Delhi 110029, India. Electronic address: dodulmondal@gmail.com.
Dodul
D
Mondal
Department of Radiation Oncology, All India Institute of Medical Sciences, New Delhi 110029, India.
Pramod Kumar
PK
Julka
Department of Radiation Oncology, All India Institute of Medical Sciences, New Delhi 110029, India.
Daya Nand
DN
Sharma
Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi 110029, India.
Manisha
M
Jana
Department of Radiation Oncology and Medical Physics, All India Institute of Medical Sciences, New Delhi 110029, India.
Macharla Anjaneyelu
MA
Laviraj
Department of Surgical Oncology, All India Institute of Medical Sciences, New Delhi 110029, India.
Suryanarayan Vs
SV
Deo
Department of Radiation Oncology, All India Institute of Medical Sciences, New Delhi 110029, India.
Soumyajit
S
Roy
Department of Pulmonary Medicine, All India Institute of Medical Sciences, New Delhi 110029, India.
Randeep
R
Guleria
Department of Radiation Oncology, All India Institute of Medical Sciences, New Delhi 110029, India.
Goura K
GK
Rath
D000328:Adult; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy* / Q000601:surgery; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D007194:India; D015412:Mastectomy, Segmental; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011182:Postoperative Care; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods; D062606:Tertiary Care Centers; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D014408:Biomarkers, Tumor
Accelerated hypofractionation; Early breast cancer; Simultaneous integrated boost; Volumetric modulated arc therapy