With great interest, we read the recent article by Tsuchiya et al. [1]. In this paper, the authors tried to identify, in the adjuvant setting after breast-conserving surgery, the optimal radiation technique for selected 25 small breast glands (median volume, 552.6 cc), comparing the dose distribution obtained with the standard wedge tangential technique (SWT), tangential-field intensity-modulated radiation therapy (T-IMRT), and 3–4 field IMRT techniques (3FIMRT or 4F-IMRT). An improved dose distribution, a shorter treatment time, and a reduction of Radiation Therapy Oncology Group (RTOG) acute high-grade skin toxicity with the T-IMRT technique [2, 3], which can be considered a simplified form of IMRT based on two tangential fields with sub-segments, have been demonstrated [4]. In their paper, Tsuchiya et al. stated that T-IMRT can be appropriate in particular for irradiation of small breasts, because of an improvement in dose homogeneity and in the dose received by 2 % of the volume (Dmax), reducing the bilateral lung mean dose and the V20 ipsilateral lung volume, compared with the other reported techniques [1]. In our unpublished data on 30 selected patients, we have pointed out that T-IMRT leads to reducing the cutaneous acute high-grade toxicity according to the RTOG scale even if the volume of our Italian breast cancer patients was higher than the Asian one (mean 910 cc, median 775 cc). In our clinical records, the tangential technique with 6 MV photons, comparing the standard wedge tangential technique (SWT) versus T-IMRT, was used, and several dosimetric parameters for planning target volume (PTV) and organs at risks (OARs) were analyzed [3]. The collapsed cone (CC) dose calculation algorithm was applied instead of the pencil beam classic (PBC) calculation model, and a statistical analysis was performed with Student t test (p \ 0.05). T-IMRT was superior to the SWT in reducing the percentage of the PTV receiving more than 110 % (V110 %) and 107 % (V107 %) prescribed dose as well as Dmax. The reduction of V110 %, V107 %, and Dmax was 50, 30, and 3 %, respectively, without compromising PTV coverage (no significant reduction of V95 % and D98) [5]. Comparing T-IMRT with SWT, our data showed no significant dosimetric differences for the heart (Dmean, V10, V20, V30 and V50) and lung (Dmax, Dmean, V10, V20, V30 and V50) but a significant reduction of hot spots, calculated as Dmax and V50. A significantly lower dose with T-IMRT (5 % reduction for Dmean) was recorded for the controlateral breast. Furthermore, a comparison between the ipsilateral lung dose distributions obtained with CC versus PBC, for T-IMRT only, showed that the use of PBC undervalues M. G. Ruo Redda (&) S. M. Anglesio S. Allis R. Verna A. Girardi E. Trevisiol A. Reali Department of Oncology, Radiation Oncology, University of Turin, S. Luigi Gonzaga Hospital, Regione Gonzole 10, Orbassano, 10043 Turin, Italy e-mail: mariagrazia.ruoredda@unito.it