Concurrent radiotherapy and gemcitabine for unresectable pancreatic adenocarcinoma: impact of adjuvant chemotherapy on survival.
OBJECTIVE
To retrospectively analyze results of concurrent chemoradiotherapy (CCRT) using gemcitabine (GEM) for unresectable pancreatic adenocarcinoma.


METHODS
Records of 108 patients treated with concurrent external beam radiotherapy (EBRT) and GEM were reviewed. The median dose of EBRT in all 108 patients was 50.4 Gy (range, 3.6-60.8 Gy), usually administered in conventional fractionations (1.8-2 Gy/day). During radiotherapy, most patients received GEM at a dosage of 250 to 350 mg/m(2) intravenously weekly for approximately 6 weeks. After CCRT, 59 patients (54.6%) were treated with adjuvant chemotherapy (AC), mainly with GEM. The median follow-up for all 108 patients was 11.0 months (range, 0.4-37.9 months).


RESULTS
Initial responses after CCRT for 85 patients were partial response: 26 patients, no change: 51 patients and progressive disease: 8 patients. Local progression was observed in 35 patients (32.4%), and the 2-year local control (LC) rate in all patients was 41.9%. Patients treated with total doses of 50 Gy or more had significantly more favorable LC rates (2-year LC rate, 42.9%) than patients treated with total doses of less than 50 Gy (2-year LC rate, 29.6%). Regional lymph node recurrence was found in only 1 patient, and none of the 57 patients with clinical N0 disease had regional lymph node recurrence. The 2-year overall survival (OS) rate and the median survival time in all patients were 23.5% and 11.6 months, respectively. Patients treated with AC had significantly more favorable OS rates (2-year OS, 31.8%) than those treated without AC (2-year OS, 12.4%; p < 0.0001). On multivariate analysis, AC use and clinical T stage were significant prognostic factors for OS.


CONCLUSIONS
CCRT using GEM yields a relatively favorable LC rate for unresectable pancreatic adenocarcinoma, and CCRT with AC conferred a survival benefit compared to CCRT without AC.
Department of Radiology, University of the Ryukyus, Okinawa, Japan. kogawa@med.u-ryukyu.ac.jp
Kazuhiko
K
Ogawa
Yoshinori
Y
Ito
Naoki
N
Hirokawa
Keiko
K
Shibuya
Masaki
M
Kokubo
Etsuyo
E
Ogo
Hitoshi
H
Shibuya
Tsutomu
T
Saito
Hiroshi
H
Onishi
Katsuyuki
K
Karasawa
Kenji
K
Nemoto
Yasumasa
Y
Nishimura
D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000627:therapeutic use*; D059248:Chemoradiotherapy / Q000379:methods* / Q000401:mortality; D017024:Chemotherapy, Adjuvant / Q000401:mortality; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D047368:Tumor Burden; D000093542:Gemcitabine
D000964:Antimetabolites, Antineoplastic; D011838:Radiation-Sensitizing Agents; D003841:Deoxycytidine; D000093542:Gemcitabine