Involved-field radiotherapy (IFRT) versus elective nodal irradiation (ENI) in combination with concurrent chemotherapy for 239 esophageal cancers: a single institutional retrospective study.
BACKGROUND
This retrospective study on early and locally advanced esophageal cancer was conducted to evaluate locoregional failure and its impact on survival by comparing involved field radiotherapy (IFRT) with elective nodal irradiation (ENI) in combination with concurrent chemotherapy.


METHODS
We assessed all patients with esophageal cancer of stages I-IV treated with definitive radiotherapy from June 2000 to March 2014. Between 2000 and 2011, ENI was used for all cases excluding high age cases. After Feb 2011, a prospective study about IFRT was started, and therefore IFRT was used since then for all cases. Concurrent chemotherapy regimen was nedaplatin (80 mg/m(2) at D1 and D29) and 5-fluorouracil (800 mg/m(2) at D1-4 and D29-32).


RESULTS
Of the 239 consecutive patients assessed (120 ENI vs. 119 IFRT), 59 patients (24.7%) had stage IV disease and all patients received at least one cycle of chemotherapy. The median follow-up time for survivors was 34.0 months. There were differences in 3-year local control (44.8% vs. 55.5%, p = 0.039), distant control (53.8% vs. 69.9%, p = 0.021) and overall survival (34.8% vs. 51.6%, p = 0.087) rates between ENI vs. IFRT, respectively. Patients treated with IFRT (8 %) demonstrated a significantly lower risk (p = 0.047) of high grade late toxicities than with ENI (16%). IFRT did not increase the risk of initially uninvolved or isolated nodal failures (27.5% in ENI and 13.4% in IFRT).


CONCLUSIONS
Nodal failure rates in clinically uninvolved nodal stations were not increased with IFRT when compared to ENI. IFRT also resulted in significantly decreased esophageal toxicity, suggesting that IFRT may allow for integration of concurrent systemic chemotherapy in a greater proportion of patients. Both tendencies of improved loco-regional progression-free survival and a significant increased overall survival rate favored the IFRT arm over the ENI arm in this study.
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. yamachan07291973@yahoo.co.jp.
Hideomi
H
Yamashita
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. rtakenaka-tky@umin.ac.jp.
Ryousuke
R
Takenaka
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. mami_oomori@yahoo.co.jp.
Mami
M
Omori
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. m035402@yahoo.co.jp.
Toshikazu
T
Imae
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. kaebear7@yahoo.co.jp.
Kae
K
Okuma
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. kotomo-tky@umin.ac.jp.
Kuni
K
Ohtomo
Department of Radiology, University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. nakagawa-rad@umin.ac.jp.
Keiichi
K
Nakagawa
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage; D059248:Chemoradiotherapy / Q000379:methods*; D018572:Disease-Free Survival; D004938:Esophageal Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000528:radiation effects; D015182:Lymphatic Irradiation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal / Q000379:methods; D012189:Retrospective Studies
D009944:Organoplatinum Compounds; C053989:nedaplatin; D005472:Fluorouracil