Influence of XRCC4 expression by breast cancer cells on ipsilateral recurrence after breast-conserving therapy

• Published in: Strahlentherapie und Onkologie 2019-07, Vol.195 (7), p.648-658
• Main Authors: Kitagawa, Mio, Someya, Masanori, Hasegawa, Tomokazu, Mikami, Toshihiko, Asaishi, Kazuaki, Hasegawa, Tadashi, Matsumoto, Yoshihisa, Kutomi, Goro, Takemasa, Ichiro, Sakata, Koh-ichi
• Format: Article
• Language: English
• Subjects: Adult; Aged; Breast cancer; Breast Neoplasms - genetics; Breast Neoplasms - mortality; Breast Neoplasms - pathology; Breast Neoplasms - surgery; Cancer; Carcinoma, Ductal - genetics; Carcinoma, Ductal - mortality; Carcinoma, Ductal - pathology; Carcinoma, Lobular - genetics; Carcinoma, Lobular - mortality; Carcinoma, Lobular - pathology; Cohort Studies; DNA-Binding Proteins - genetics; Female; Humans; Mastectomy; Mastectomy, Segmental; Matching; Medicine; Medicine & Public Health; Middle Aged; Neoplasm Recurrence, Local - genetics; Neoplasm Recurrence, Local - mortality; Neoplasm Recurrence, Local - pathology; Neoplasm Staging; Neoplasms, Second Primary - genetics; Neoplasms, Second Primary - mortality; Neoplasms, Second Primary - pathology; Oncology; Original Article; Patients; Prognosis; Propensity Score; Proteins; Radiation therapy; Radiotherapy; Survival Rate; Therapy; Tumors
• ISSN: 0179-7158; 1439-099X
• DOI: 10.1007/s00066-019-01468-z

Background We examined the expression of nonhomologous end-joining (NHEJ) proteins by breast cancer cells in patients with or without ipsilateral breast tumor recurrence (IBTR) after breast-conserving therapy. We also investigated whether there was a difference of NHEJ-related protein expression by tumor cells between two types of IBTR, i.e., true recurrence (TR) with regrowth from the tumor bed or development of a new primary tumor (NP). Patients and methods The original cohort comprised 560 breast cancer patients who received breast-conserving therapy between February 1995 and March 2006, including 520 patients without IBTR and 40 patients with IBTR. Propensity score matching was employed to select 40 trios (120 patients) consisting of 1 patient with IBTR and 2 patients without IBTR. Immunohistochemical examination of proteins related to NHEJ was performed in surgical specimens. Results The 40 patients with IBTR included 22 patients who developed TR and 18 who had NP. The 15-year overall survival rate was 85.9% for patients with NP and 95.5% for those with TR, while it was 96.5% for patients without IBTR. Patients with high XRCC4 expression in tumor cells had significantly higher IBTR rates than those with low XRCC4 expression ( P