Mono versus dual isocentric technique for breast cancer radiotherapy: Evaluation of planning, dosimetry and treatment delivery

Tabassum Wadasadawala, Shirley Lewis, Utpal Gaikwad, Umesh Gayake, Reena Phurailatpam, Santosh Tambe, Rajiv Sarin

Research output: Contribution to journalArticlepeer-review

Abstract

Aim:To compare the dosimetry and reproducibility of set-up with monoisocentric technique (MIT) and dual isocentric technique (DIT) in adjuvant breast radiotherapy (RT).Material and methods:Breast cancer patients treated with MIT or DIT were retrospectively studied. The organ-at-risk dose was compared between two groups. All patients underwent set-up verification with an electronic portal imaging device, and set-up time was recorded for each fraction. Treatment reproducibility was assessed in terms of systematic and random error.Results:Twenty patients were included (11 right and 9 left-sided tumours) and ten received whole breast RT, while the rest received chest wall RT. Overall, the mean heart dose was less with MIT (0.40 versus 0.79, p = <0.001) as well as in left-sided tumours (0.37 versus 0.98, p = 0.003). The maximum dose at the field junction was significantly higher with DIT (43 Gy, 107%, p = 0.003). The maximum total error was 1 cm in lateral for supraclavicular field and 8 mm in superior-inferior in tangents for both techniques. There was no difference in set-up errors between the two techniques.Findings:MIT resulted in better dose homogeneity at the field junctions and reduced mean heart dose as compared to DIT. MIT is safe for implementation in clinical practice for breast cancer treatment.Conclusion:This study is one of the few studies comparing MIT with DIT in terms of the dosimetry and the first one to compare set-up errors between the two techniques. The ease of set-up and better dosimetry with MIT was achieved.

Original languageEnglish
JournalJournal of Radiotherapy in Practice
DOIs
Publication statusAccepted/In press - 2020

All Science Journal Classification (ASJC) codes

  • Radiology Nuclear Medicine and imaging
  • Oncology

Fingerprint Dive into the research topics of 'Mono versus dual isocentric technique for breast cancer radiotherapy: Evaluation of planning, dosimetry and treatment delivery'. Together they form a unique fingerprint.

Cite this