Dosimetric study and in-vivo dose verification for conformal avoidance treatment of anal adenocarcinoma using helical tomotherapy

Han, Chunhui; Chen, Yi-Jen; Liu, An; Schultheiss, Timothy E.; Wong, Jeffrey Y.C.

doi:10.1016/j.meddos.2006.10.004

« Previous Next »Medical Dosimetry
Volume 32, Issue 1 , Pages 33-37, Spring 2007

Dosimetric study and in-vivo dose verification for conformal avoidance treatment of anal adenocarcinoma using helical tomotherapy

This study was presented as a poster in the 48th American Association of Physicists in Medicine (AAPM) Annual Meeting in Orlando, Florida, July 30-August 3, 2006.

Chunhui Han, Ph.D.
- Department of Radiation Physics, City of Hope National Medical Center, Duarte, CA, USA
- Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
- Reprint requests to: Chunhui Han, Ph.D., Department of Radiation Physics, City of Hope National Medical Center, 1500 Duarte Rd., Duarte, CA 91010.
Yi-Jen Chen, Ph.D., M.D.
- Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
An Liu, Ph.D.
- Department of Radiation Physics, City of Hope National Medical Center, Duarte, CA, USA
- Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
Timothy E. Schultheiss, Ph.D.
- Department of Radiation Physics, City of Hope National Medical Center, Duarte, CA, USA
- Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
Jeffrey Y.C. Wong, M.D.
- Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA

Received 21 October 2006; accepted 24 October 2006.

Abstract

This study evaluated the efficacy of using helical tomotherapy for conformal avoidance treatment of anal adenocarcinoma. We retrospectively generated step-and-shoot intensity-modulated radiotherapy (sIMRT) plans and helical tomotherapy plans for two anal cancer patients, one male and one female, who were treated by the sIMRT technique. Dose parameters for the planning target volume (PTV) and the organs-at-risk (OARs) were compared between the sIMRT and the helical tomotherapy plans. The helical tomotherapy plans showed better dose homogeneity in the PTV, better dose conformity around the PTV, and, therefore, better sparing of nearby OARs compared with the sIMRT plans. In-vivo skin dose measurements were performed during conformal avoidance helical tomotherapy treatment of an anal cancer patient to verify adequate delivery of skin dose and sparing of OARs.

Key Words: Helical tomotherapy, Conformal avoidance, Intensity-modulated radiotherapy, Anal cancer