High epidermal growth factor receptor expression in metastatic colorectal cancer lymph nodes may be more prognostic of poor survival than in primary tumor.
OBJECTIVE
High epidermal growth factor receptor (EGFR) expression in the primary tumor predicts poor survival in colorectal cancer. However, EGFR expression may be discordant in primary tumor versus nodal or distant metastasis. We evaluated prognostic values of high EGFR expression in nodal metastasis versus primary tumor tissue.


METHODS
Tissue microarrays from 94 surgically resected colorectal primary tumors were analyzed for EGFR expression using immunohistochemistry along with 49 paired positive metastatic nodes and 19 distant metastases. Proportional odds regression and log-rank tests described the association of tumor stage and survival with EGFR, dichotomized to low expression (0, 1) versus high expression (2, 3).


RESULTS
High EGFR expression rates in the primary tumor, metastatic lymph node and distant metastases were 18%, 24%, and 21%, respectively. The concordance rate was 71% for stage III/IV patients. High EGFR expression in primary tumor was associated with higher tumor stage (odds ratio 4.3, P = 0.005) and thus predicted poor survival (P = 0.046). High EGFR expression in the primary tumor was not associated with survival in patients with stage III or IV disease, whereas high EGFR expression in metastatic lymph nodes was associated with relatively poor survival (P = 0.005), for both stage III (P = 0.002) and stage IV patients (P = 0.014). Concordant high EGFR expression in primary tumor and lymph nodes conferred added risk of death (P = 0.003), conversely, concordant EGFR-negative primary tumor and lymph node was protective (P = 0.097).


CONCLUSIONS
EGFR expression may be discordant among primary, nodes, and metastases in colorectal cancer. High EGFR expressions in metastatic lymph nodes seem to be more accurate in predicting survival than in primary or metastatic tissues.
Deng
Yanhong
Y
Department of Medical Oncology of Cancer Center, Sun Yatsen University, Guangzhou, People's Republic of China, China.
Kurland
Brenda F
BF
Wang
Jianping
J
Bi
Jiong
J
Li
Wen
W
Rao
Sujata
S
Lan
Ping
P
Lin
Tongyu
T
Lin
Edward
E
D000230:Adenocarcinoma / Q000188:drug therapy / Q000378:metabolism* / Q000401:mortality; D002288:Adenocarcinoma, Mucinous / Q000188:drug therapy / Q000378:metabolism* / Q000401:mortality; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000401:mortality; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate; D046888:Tissue Array Analysis; D016896:Treatment Outcome; D055815:Young Adult
D000970:Antineoplastic Agents; C512478:EGFR protein, human; D066246:ErbB Receptors