Preoperative Radiotherapy Plus Skin-Sparring Mastectomy and Immediate DIEP Flap Reconstruction Safe, Feasible in Breast Cancer

Perioperative radiotherapy followed by skin-sparing mastectomy and immediate deep inferior epigastric perforator flap reconstruction (DIEP) was deemed safe for patients with primary breast cancer, with investigators reporting rates of breast open wounds that were comparable with post-mastectomy radiotherapy, according to a study published in The Lancet Oncology.

Four weeks following surgery, 12.1% (n = 4/33; 95% CI, 3.4%-28.2%) of patients had breast open wounds greater than 1 cm. However, the wounds were considered to be minor and were treated with dressings and antibiotics (n = 3), or reoperation for debridement and skin graft (n = 1). Twenty-four hours after surgery, only 1 other patient was taken back in for surgery for a congested flap, although this did not require intervention.

A total of 33 patients were enrolled on the trial. Thirty-one patients received preoperative radiotherapy before completion of masectomy and 2 patients received it before completion of the mastectomy. No patients dropped out during this trial.

Four of 33 patients at 8 weeks after surgery and no patients at 12-weeks had a breast open wound of greater than 1 cm that required a dressing. At a median follow-up of 23.6 months there were no DIEP failures. Additionally, 17 patients who participated at the Royal Marsden NHS Foundation completed aesthetic assessments, and 14 completed the BREAST-Q questionnaire preoperatively, 13 completed it 3 months after surgery, and 12 completed it 12 months after surgery.

At 3- and 12-months post-surgery, 13 and 12 patients, respectively, that had 3D-surface imaging panel evaluations. At baseline, the median satisfaction with the breasts Q score was 48.0, 73.0 at 3 months post-surgery, and 77.0 at 12 months. Globally, the median 3D-surface imaging panel score was 3.9 of 5.0 at 3 months and 4.3 at 12 months.

Neoadjuvant chemotherapy was not administered to 3 of 33 patients, all of whom were excluded from calculations of the timelines of neoadjuvant chemotherapy to preoperative radiotherapy and neoadjuvant chemotherapy to mastectomy. Within 4 weeks of preoperative radiotherapy, 27 patients had surgery; everyone had surgery within 6 weeks.

The breast pathological complete response (pCR) was 21% of patients (95% CI, 8.98%-38.91%), and the axillary pCR rate was 26% (95% CI, 10.23%-48.41%). There were no cases local or regional nodal recurrences at follow-up. However, 4 patients had distant metastatic disease, and 2 died from breast cancer.

Investigators reported that the overall survival rate was 93.9% (95% CI, 79.7%-99.2%), and the disease-free survival rate was 84.8% (95% CI, 68.1%-94.9%).

A dose reduction was necessary in 10 patients who received neoadjuvant chemotherapy. Of the patients who received preoperative radiotherapy, 29 received 40 Gy in 15 fractions, and 4 received 42.72 Gy in 16 fractions. Additionally, regional nodal radiotherapy was administered to the axilla (n = 12), supraclavicular fossa (n = 29), and internal mammary (n = 11). Overall, 4 patients did not receive regional nodal radiotherapy.

In terms of toxicity, 1 patient had grade 0 skin toxicity, 22 had grade 1, and 9 had grade 2. Additionally, grade 3 confluent moist desquamation was re[prted in 1 patient. There were no grade 4 adverse effects (AEs), and no patients discontinued treatment due to toxicities. Patients also did not experience serious AEs or treatment-related deaths.

Reference

Thiruchelvam PTR, Leff DR, Godden AR, et al. Primary radiotherapy and deep inferior epigastric perforator flap reconstruction for patients with breast cancer (PRADA): a multicentre, prospective, non-randomised, feasibility study. Lancet Oncol. 2022;23(5):682-690. doi:10.1016/S1470-2045(22)00145-0