Does Internal Mammary Node Irradiation Have Survival Benefit for Clinical Stage II-III Breast Cancer Patients After Neoadjuvant Chemotherapy?

and each assessment consisted of graduation of RDT severity, and documentation of any treatment interruptions and expenditures related to local care of RDT. Toxicity was graded according to Common Terminology Criteria for Adverse Events (CTCAE v4.0). Results: The incidence of grade 3 RDT in groups A, B, C, and D were 0%, 0%, 13%, and 88%, respectively. For HR group, there was a significant difference between the arms C and D (pZ 0.007), regarding grade 3 RDT. For SR group, there was no difference between the arms A and B (p Z 0.69), regarding grade 2 and lower toxicity. The only factors associated with the development of grade 3 RDT were daily use of bolus (p Z 0.0007) and supraclavicular fossa irradiation (p Z 0.016). Mean expenditures with local care in groups A, B + C, and D were $68, $70, and $258, respectively (p < 0.001). For the whole group, three treatment interruptions occurred, all in the HR arms, with no difference regarding the pattern of bolus use (p Z 0.93), A relation between the severity of the RDT after the second week of treatment and the appearance of grade 3 RDT was observed, with daily use of bolus. Conclusions: The use of daily 5 mm bolus is associated to higher incidence of grade 3 RDT. Daily bolus was also associated to higher expenditures with local care related to RDT. Further studies are necessary to evaluate the oncological benefit and cost-effectiveness of tissue-equivalent bolus in PMRT. Author Disclosure: L. Sapienza: None. M.J. Chen: None. K.C. Trigo: None. M.L. Silva: None. D.G. Castro: None. R.C. Fogaroli: None. A.C. Pellizzon: None. M.C. Maia: None.