Ultrasound accuracy in determining the tumor depth for boost field radiotherapy in breast cancer in comparison with CT scan plus clips

Background: There are miscellaneous methods of boost field determination with different levels of accuracy. One of the important parameters in boost field planning is the tumor bed depth, as it is important for determining electron energy

Objectives: The purpose of present research was the determination of ultrasound accuracy to estimate the appropriate depth for the tumor bed

Patients and Methods: Patients who were undergone breast conservative surgery with placing of 5 clips in the tumor bed [lower, upper, medial, lateral, and posterior] were included. The depth and location of the tumor bed were determined using ultrasonography. The optimum field boost was planned with an appropriate 2.5 cm margin. After putting the marker on the field boost, the CT simulation was done and then the obtained depth of the ultrasound report and that of the CT scan-clips were compared

Results: Twenty five patients were included. The average depth reported by the ultrasound was about 18 mm +/- 3 mm [range 10-26 mm], and the average obtained from the CT scan-clips was about 48 mm +/- 13 mm [range 24-80 mm], [P Value = 0.001]. In almost all cases, the depth obtained from the ultrasound was less than that obtained from the CT scan- clips

Conclusions: Ultrasound is not an accurate method to determine the appropriate depth and field for determination of breast field boost. Thus, it is better not to use ultrasound to estimate the tumor cavity depth; the CT scan images with surgical clips should be used instead

[Comparing the effects of conventional and hypofractionated radiotherapies on early skin toxicity and cosmetic outcomes after breast cancer conserving surgery]

The high number of breast cancer patients who receive radiation therapy after surgery has caused many to think about a shorter period of radiotherapy, which can significantly reduce the radiotherapy machine time, labor hours, and fewer patient visits. This study was designed to evaluate the acute skin effects and cosmetic outcomes of short course radiotherapy in early-stage breast cancer in comparison with the conventional treatment method. Fifty-two patients with operable breast cancer [pT1-3pN0M0] who underwent breast conservation surgery in Tehran Cancer Institute during January 2011 to January 2012, were randomly assigned to undergo radiotherapy by either receiving conventional treatment [dose: 50 Gy in 25 fractions] with subsequent electron boost or a short-course hypofractionated radiotherapy [dose: 42.5 Gy in 16 fractions] and a subsequent electron boost. There were no skin changes during the first or the second week of treatment in the two groups. Cutaneous complications began after the third week as grade 1 skin toxicity after termination of the short-course radiotherapy but there were no difference in complication rate after four weeks of treatment. Six months and one year after treatment, there were no differences in terms of skin complications or cosmetic outcomes between the two groups. Although the use of a whole-breast irradiation with a hypofractionated schedule was associated with desirable outcomes, in term of skin toxicity and cosmetics, but longer follow-up periods with larger sample sizes are needed to confirm these results.