Rad51 expression is a useful predictive factor for the efficacy of neoadjuvant chemoradiotherapy in squamous cell carcinoma of the esophagus.
BACKGROUND
Neoadjuvant chemoradiotherapy (NACRT) for esophageal squamous cell carcinoma (ESCC) is beneficial in the setting of a complete pathological response. Rad51 expression affects both chemo- and radiosensitivity in many cancers; however, its role in ESCC is unclear.


METHODS
Rad51 expression was investigated by immunohistochemical staining with resected specimens in 89 ESCC patients who underwent surgery without preoperative therapy. The association with Rad51 and clinicopathological factors was assessed. The expression of Rad51 was also investigated in pretreatment biopsy specimens in 39 ESCC patients who underwent surgery after NACRT and compared with the pathological response to NACRT.


RESULTS
Lymph node metastasis was more frequently observed in Rad51-positive cases than negative cases (58.5 vs. 30.6%, P = 0.0168) in patients treated with surgery alone. Disease-specific survival was decreased in Rad51-positive cases compared to Rad51-negative cases (5 year survival: 79.6 vs. 59.3%, P = 0.0324). In NACRT patients, completed pathological responses were more frequently observed in Rad51-negative cases than in Rad51-positive cases (68.8 vs. 46.5%, P = 0.0171).


CONCLUSIONS
Rad51 expression in ESCC was associated with lymph node metastasis and poor survival. Additionally, Rad51 expression in pretreatment biopsy specimens was a predictive factor for the response to NACRT.
Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, nakanoko@surg2.med.kyushu-u.ac.jp.
Tomonori
T
Nakanoko
Hiroshi
H
Saeki
Masaru
M
Morita
Yuichiro
Y
Nakashima
Koji
K
Ando
Eiji
E
Oki
Takefumi
T
Ohga
Yoshihiro
Y
Kakeji
Yasushi
Y
Toh
Yoshihiko
Y
Maehara
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000401:mortality / Q000556:secondary / Q000628:therapy; D059248:Chemoradiotherapy; D004938:Esophageal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D009367:Neoplasm Staging; D011379:Prognosis; D051135:Rad51 Recombinase / Q000378:metabolism*; D015996:Survival Rate
D014408:Biomarkers, Tumor; C495153:RAD51 protein, human; D051135:Rad51 Recombinase