TS expression predicts postoperative recurrence in adenocarcinoma of the lung.
BACKGROUND
Not all patients with lung cancer require postoperative adjuvant chemotherapy after a complete resection. However, no useful markers for either selecting appropriate candidates or for predicting clinical recurrence exist.


METHODS
Tumor specimens were collected from 183 consecutive patients who underwent a complete resection for lung adenocarcinoma from 2003 to 2007 in our department. We analyzed the thymidylate synthase (TS) and dihydrofolate reductase (DHFR) expressions in the primary lung adenocarcinoma by immunohistochemisty.


RESULTS
The strong expression of TS and DHFR was identified in 39 (21.3%) and 120 (65.6%) patients, respectively. The strong TS expression was identified in 11 (39.3%) of 28 patients and 28 (18.1%) of 155 patients in patients with and without recurrence, respectively (p=0.012). The strong DHFR expression was also identified in 23 (82.1%) and 97 (62.6%) of the patients with and without recurrence, respectively (p=0.045). Logistic regression models indicated the strong TS expression to be an independent factor for tumor recurrence. The strong TS and DHFR expression was associated with a poorer disease-free survival (DFS) according to the survival analysis. A multivariate analysis demonstrated the strong TS expression to be independently associated with an increased risk for poor DFS.


CONCLUSIONS
The strong TS expression may be a useful marker for predicting postoperative recurrence in patients with lung adenocarcinoma following surgery.
Second Department of Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Hidehiko
H
Shimokawa
Hidetaka
H
Uramoto
Takamitsu
T
Onitsuka
Teruo
T
Iwata
Makoto
M
Nakagawa
Kenji
K
Ono
Takeshi
T
Hanagiri
D000230:Adenocarcinoma / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011013:Pneumonectomy; D011379:Prognosis; D013762:Tetrahydrofolate Dehydrogenase / Q000378:metabolism; D013940:Thymidylate Synthase / Q000378:metabolism*; D016896:Treatment Outcome
D014408:Biomarkers, Tumor; D013762:Tetrahydrofolate Dehydrogenase; D013940:Thymidylate Synthase