TY - JOUR
T1 - Molecular prognostic factors in rectal cancer treated by radiation and surgery
AU - Qiu, Hongming
AU - Sirivongs, Prayuth
AU - Rothenberger, Meghan K
AU - Rothenberger, David A
AU - García-Aguilar, Julio
PY - 2000/4
Y1 - 2000/4
N2 - PURPOSE: The aim of this study was to determine the biologic significance of tumor response and the prognostic value of molecular markers in a group of patients with rectal cancer treated with preoperative radiation therapy and radical surgery. METHODS: Microsatellite instability, microvessel count, and immunohistochemistry for proliferating cell nuclear antigen, p53, p21, bcl-2, and vascular endothelial growth factor were performed in the preradiation biopsy specimen of 72 patients with rectal cancer treated by preoperative radiation therapy and radical curative surgery. Preoperative tumor stage by endorectal ultrasound was compared with pathology stage of the resected specimen. Mean follow-up was 50 months. RESULTS: Twenty-eight patients (39 percent) responded to radiation therapy. The response was complete in 8 (12 percent) and partial in 20 patients (27 percent). Tumors with positive nodes in the surgical specimen were less likely to have responded to preoperative radiation (P = 0.03). Only p21 expression was individually associated with response to radiation (56 vs. 30 percent; P = 0.03). Tumors that were p53-negative/p21-positive or p21-positive/bcl-2- positive were also more likely to respond to radiation (83 vs. 35 percent; P = 0.03 and 71 vs. 31 percent; P = 0.01, respectively). The tumor relapsed in 21 patients (29 percent): locally in 7 (10 percent) and distally in 14 (19 percent). Recurrence was associated with lack of response to radiation, female gender, distal tumor location, high proliferating cell nuclear antigen labeling index, and low microvessel count. Probability of survival was greater for patients with well or moderately differentiated tumors and tumors that responded completely to radiation. CONCLUSIONS: Tumor response to radiation is associated with improved tumor control and overall survival rate, and p21 expression is a marker of tumor radiosensitivity in patients with rectal cancer. Furthermore, a high proliferating cell nuclear antigen labeling index and a low microvessel count in the preradiation biopsy specimen may be prognostic indicators for tumor recurrence.
AB - PURPOSE: The aim of this study was to determine the biologic significance of tumor response and the prognostic value of molecular markers in a group of patients with rectal cancer treated with preoperative radiation therapy and radical surgery. METHODS: Microsatellite instability, microvessel count, and immunohistochemistry for proliferating cell nuclear antigen, p53, p21, bcl-2, and vascular endothelial growth factor were performed in the preradiation biopsy specimen of 72 patients with rectal cancer treated by preoperative radiation therapy and radical curative surgery. Preoperative tumor stage by endorectal ultrasound was compared with pathology stage of the resected specimen. Mean follow-up was 50 months. RESULTS: Twenty-eight patients (39 percent) responded to radiation therapy. The response was complete in 8 (12 percent) and partial in 20 patients (27 percent). Tumors with positive nodes in the surgical specimen were less likely to have responded to preoperative radiation (P = 0.03). Only p21 expression was individually associated with response to radiation (56 vs. 30 percent; P = 0.03). Tumors that were p53-negative/p21-positive or p21-positive/bcl-2- positive were also more likely to respond to radiation (83 vs. 35 percent; P = 0.03 and 71 vs. 31 percent; P = 0.01, respectively). The tumor relapsed in 21 patients (29 percent): locally in 7 (10 percent) and distally in 14 (19 percent). Recurrence was associated with lack of response to radiation, female gender, distal tumor location, high proliferating cell nuclear antigen labeling index, and low microvessel count. Probability of survival was greater for patients with well or moderately differentiated tumors and tumors that responded completely to radiation. CONCLUSIONS: Tumor response to radiation is associated with improved tumor control and overall survival rate, and p21 expression is a marker of tumor radiosensitivity in patients with rectal cancer. Furthermore, a high proliferating cell nuclear antigen labeling index and a low microvessel count in the preradiation biopsy specimen may be prognostic indicators for tumor recurrence.
KW - MSI
KW - Microvessel count
KW - PCNA
KW - Radiation therapy
KW - Rectal cancer
KW - VEGF
KW - bcl-2
KW - p21
KW - p53
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UR - http://www.scopus.com/inward/citedby.url?scp=0033994163&partnerID=8YFLogxK
U2 - 10.1007/BF02237186
DO - 10.1007/BF02237186
M3 - Article
C2 - 10789738
AN - SCOPUS:0033994163
SN - 0012-3706
VL - 43
SP - 451
EP - 459
JO - Diseases of the colon and rectum
JF - Diseases of the colon and rectum
IS - 4
ER -