Daily boost.

Headline: Concurrent lumpectomy boost results in noninferior local control and similar cosmesis when compared to the tried and true sequential boost.

The Study: RTOG 1005 was designed in 2011, looking to decrease the 4-week standard by another week. A remarkable 2262 women were randomized to [1] sequential boost of 12-14 Gy in 6-7 fractions following 50 Gy in 25 or 42.7 Gy in 16 whole breast irradiation or [2] concomitant boost of 0.53 Gy per day during whole breast irradiation of 40 Gy in 15 (total boost dose of 48 Gy in 15). The key adjective here is “concomitant” and not “simultaneous integrated” because 4 in 5 women received 3D-conformal radiation. The smaller cone-down boost was delivered during the same treatment session, but after treating the whole breast fields. The primary endpoint of ipsilateral breast recurrence was non-inferior at 7 years (2.2 v 2.6%, respectively), and there was no difference in grade 3+ toxicity (3.3 v 3.5%) or good to excellent cosmesis (86 v 84%).

TBL: Delivering a 48 Gy in 15 fractions concomitant boost during moderately hypofractionated whole breast radiation results in non-inferior local and toxicity and cosmesis that are comparable to a sequential boost technique. | Vicini, ASTRO 2022