Dominant papillary subtype is a significant predictor of the response to gefitinib in adenocarcinoma of the lung.
OBJECTIVE
Gefitinib (IRESSA; AstraZeneca, Osaka, Japan) shows excellent antitumor activity against advanced non-small-cell lung cancer, especially for the treatment of adenocarcinoma. However, the predictive factors for the response to gefitinib are still controversial. The aim of this study was to identify the clinicopathological and immunohistochemical features that are favorable to the use of gefitinib in adenocarcinoma patients.


METHODS
Between June 2002 and October 2003, 36 adenocarcinoma patients who experienced a relapse after surgical resection were treated with gefitinib at our hospital. The histologic patterns of the tumors were divided into four distinctive subtypes according to the revised World Health Organization histologic classification, and the dominant histologic subtype for the maximum cut surface of each resected specimen was documented. Association between the response to gefitinib and the clinicopathological features or immunohistochemical expression of epidermal growth factor receptor (EGFR), phosphorylated EGFR, or c-erbB-2 were then investigated.


RESULTS
A significant association between the response to gefitinib and dominant papillary subtype findings was observed (P = 0.0021); the survival time of papillary subtype patients was also significantly prolonged compared with that of non-papillary subtype patients (P = 0.03). No other clinicopathological features or the expression of EGFR, phosphorylated EGFR, or c-erbB-2 were associated with the response to gefitinib.


CONCLUSIONS
The results of the present study indicate that dominant papillary subtype findings of lung adenocarcinomas can be an important predictor of the response to gefitinib. Thus, this type of adenocarcinoma might be susceptible to postoperative adjuvant treatment with gefitinib.
Kim
Young Hak
YH
Pathology Division, National Cancer Center Research Institute East, Chiba, Japan.
Ishii
Genichiro
G
Goto
Koichi
K
Nagai
Kanji
K
Tsuta
Koji
K
Shiono
Satoshi
S
Nitadori
Junichi
J
Kodama
Testuro
T
Nishiwaki
Yutaka
Y
Ochiai
Atsushi
A
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000494:pharmacology*; D066246:ErbB Receptors / Q000096:biosynthesis; D005260:Female; D000077156:Gefitinib; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010766:Phosphorylation; D011799:Quinazolines / Q000494:pharmacology*; D013997:Time Factors; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D011799:Quinazolines; D066246:ErbB Receptors; D000077156:Gefitinib