The purpose of the present study was to perform an analysis of the changes in the dynamic seroma cavity based on fiducial markers in early stage breast cancer patients treated with accelerated partial breast irradiation (APBI) using three-dimensional conformal external beam radiotherapy (3D-CRT).
A prospective, single arm trial was designed to investigate the utility of gold fiducial markers in image guided APBI using 3D-CRT. At the time of lumpectomy, four to six suture-type gold fiducial markers were sutured to the walls of the cavity. Patients were treated with a fractionation scheme consisting of 15 fractions with a fractional dose of 333 cGy. Treatment design and planning followed NSABP/RTOG B-39 guidelines. During radiation treatment, daily kV imaging was performed and the markers were localized and tracked. The change in distance between fiducial markers was analyzed based on the planning CT and daily kV images.
Thirty-four patients were simulated at an average of 28 days after surgery, and started the treatment on an average of 39 days after surgery. The average intermarker distance (AiMD) between fiducial markers was strongly correlated to seroma volume. The average reduction in AiMD was 19.1% (range 0.0%–41.4%) and 10.8% (range 0.0%–35.6%) for all the patients between simulation and completion of radiotherapy, and between simulation and beginning of radiotherapy, respectively. The change of AiMD fits an exponential function with a half-life of seroma shrinkage. The average half-life for seroma shrinkage was 15 days. After accounting for the reduction which started to occur after surgery through CT simulation and treatment,radiation was found to have minimal impact on the distance change over the treatment course.
Using the marker distance change as a surrogate for seroma volume, it appears that the seroma cavity experiences an exponential reduction in size. The change in seroma size has implications in the size of the CTV, PTV, and percent of normal breast tissue irradiated when using 3D-CRT.
Received 24 January 2012Revised 26 December 2012Accepted 27 December 2012Published online 28 January 2013
This study was supported by an UMDNJ Foundation Grant (S.G.). The authors report no conflicts of interest in conducting the research.
Article outline: I. INTRODUCTION II. MATERIALS AND METHODS II.A. Patient eligibility and fiducial marker placement II.B. Radiation treatment planning II.C. Image-guidedradiation therapy technique II.D. Analysis of seroma size change and determination of optimal timing of CT simulation II.E. Statistical analysis III. RESULTS III.A. Patient characteristics III.B. Correlation between CT-based seroma size and AiMD III.C. Dynamice change of AiMD IV. DISCUSSION V. CONCLUSION
Ning J. Yue,
Bruce G. Haffty,
Sining Chen and
Source:Med. Phys. 40, 021717 (
1.T. B. Julianet al., “Early toxicity results with 3D conformal external beam therapy (CEBT) from the NSABP B-39/RTOG 0413 accelerated partial-breast irradiation (APBI) trial,” J. Clin. Oncol.29(15), 1011 (2010).
2.K. L. Baglanet al., “Accelerated partial breast irradiation using 3D conformal radiation therapy (3D-CRT),” Int. J. Radiat. Oncol. Biol. Phys.55, 302–311 (2003).
3.W. W. Suhet al., “A cost comparison analysis of partial versus whole-breast irradiation after breast-conserving surgery for early-stage breast cancer,” Int. J. Radiat. Oncol. Biol. Phys.62, 790–796 (2005).
4.A. Sandhuet al., “Prostate bed localization with image-guided approach using on-board imaging: Reporting acute toxicity and implications for radiation therapy planning following prostatectomy,” Radiother. Oncol.88, 20–25 (2008).
5.C. K. Park, J. Pritz, G. G. Zhang, K. M. Forster, and E. E. Harris, “Validating fiducial markers for image-guided radiation therapy for accelerated partial breast irradiation in early-stage breast cancer”, Int. J. Radiat. Oncol. Biol. Phys.82(3), e425–e431 (2012).
6.C. E. Coleset al., “Titanium clip placement to allow accurate tumour bed localisation following breast conserving surgery: Audit on behalf of the IMPORT Trial Management Group,” Eur. J. Surg. Oncol.35, 578–582 (2009).
9.D. W. Weedet al., “The validity of surgical clips as a radiographic surrogate for the lumpectomy cavity in image-guided accelerated partial breast irradiation,” Int. J. Radiat. Oncol. Biol. Phys.60, 484–492 (2004).
12.L. H. Kim, S. DeCesare, F. Vicini, and D. Yan, “Effect of lumpectomy cavity volume change on the clinical target volume for accelerated partial breast irradiation: A deformable registration study,” Int. J. Radiat. Oncol. Biol. Phys.78(4), 1121–1126 (2010).
13.J. B. Strauss, B. T. Gielda, S. S. Chen, A. P. Shah, R. A. Abrams, and K. L. Griem, “Variation in post-surgical lumpectomy cavity volume with delay in initiation of breast irradiation because of chemotherapy,” Int. J. Radiat. Oncol. Biol. Phys.77(3), 831–835 (2010).
15.K. Oh, F. Kong, K. Griffith, B. Yanke, and L. J. Pierce, “Planning the breast tumor bed boost: Changes in the excision cavity volume and surgical scar location after breast conserving surgery and whole-breast irradiation,” Int. J. Radiat. Oncol. Biol. Phys.66, 680–686 (2006).
16.E. J. Harris, E. M. Donovan, J. R. Yarnold, C. E. Coles, and P. M. Evans, “Characterization of target volume changes during breast radiotherapy using implanted fiducial markers and portal imaging,” Int. J. Radiat. Oncol. Biol. Phys.73(3), 958–966 (2009).
18.NSABP B-39, RTOG 0413, “A Randomized Phase III Study of conventional whole breast irradiation versus partial breast irradiation for women with stage 0, I, or II breast cancer,” Clin. Adv. Hematol. Oncol.4, 719–721 (2006).
19.E. K. Wonget al., “Consistency in seroma contouring for partial breast radiotherapy: Impact of guidelines,” Int. J. Radiat. Oncol. Biol. Phys.66, 372–376 (2006).
20.F. M. Watermanet al., “Edema associated with I-125 or Pd-103 prostate brachytherapy and its impact on post-implant dosimetry: An analysis based on serial CT acquisition,” Int. J. Radiat. Oncol. Biol. Phys.41, 1069–1177 (1998).
21.T. J. Yang, D. Minkema, P. H. Elkhuizen, W. Heemsbergen, A. M. Van Mourik, and C. Van Vliet-Vroegindeweij, “Clinical applicability of cone-beam computed tomography in monitoring seroma volume change during breast irradiation,” Int. J. Radiat. Oncol. Biol. Phys.78, 119–126 (2010).