How to boost the breast tumor bed? A multidisciplinary approach in eight steps.
OBJECTIVE
To describe a new procedure for breast radiotherapy that will improve tumor bed localization and radiotherapy treatment using a multidisciplinary approach.


METHODS
This pilot study was conducted by departments of radiation oncology, surgery, and radiology. A new procedure has been implemented, summarized as eight steps: from pre-surgery contrast CT to surgery, tumor bed planning target volume (PTV) determination, and finally breast and tumor bed irradiation.


RESULTS
Twenty patients presenting with T1N0M0 tumors were enrolled in the study. All patients underwent lumpectomy with the placement of surgical clips in the tumor bed region. During surgery, 1 to 5 clips were placed in the lumpectomy cavity before the plastic procedure. All patients underwent pre- and postoperative CT scans in the treatment position. The two sets of images were registered with a match-point registration. All volumes were contoured and the results evaluated. The PTV included the clips region, the gross tumor volume, and the surgical scar, with an overall margin of 5-10 mm in all directions, corresponding to localization and setup uncertainties. For each patient the boost PTV was discussed and compared with our standard forward-planned PTV.


CONCLUSIONS
We demonstrate the feasibility of a tumor bed localization and treatment procedure that seems adaptable to routine practice. Our study shows the advantages of a multidisciplinary approach for tumor bed localization and treatment. The use of more than 1 clip associated with pre- to postoperative CT image registration allows better definition of the PTV boost volume.
Kirova
Youlia M
YM
Department of Radiation Oncology, Institut Curie, Paris, France. youlia.kirova@curie.net
Fournier-Bidoz
Nathalie
N
Servois
Vincent
V
Laki
Fatima
F
Pollet
Guillaume A
GA
Salmon
Remy
R
Thomas
Alexandra
A
Dendale
Rémi
R
Bollet
Marc A
MA
Campana
François
F
Fourquet
Alain
A
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000601:surgery; D002985:Clinical Protocols; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D010865:Pilot Projects; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden