Prognostic significance of neuroendocrine expression in lymph node-positive prostate cancer
Received 25 March 2005; accepted 2 December 2005. published online 11 May 2006.
Abstract
Objectives
To evaluate the expression of chromogranin A, a marker for neuroendocrine (NE) differentiation, in patients with lymph node-positive prostate cancer to determine its prognostic significance. NE cells are involved in cellular growth and differentiation in both normal and pathologic conditions of the prostate.
Methods
We reviewed the data of 140 patients with lymph node-positive prostate adenocarcinoma treated with radical prostatectomy and pelvic lymphadenectomy. The median follow-up was 10.9 years (range 0.8 to 19.7). Immunohistochemical staining for chromogranin A was evaluated in areas of benign epithelium, primary prostate cancer, and lymph node metastasis. The association between chromogranin A expression and the clinical and pathologic factors (preoperative serum prostate-specific antigen and prostatectomy Gleason score and stage) and clinical outcomes, including overall and recurrence-free survival, was evaluated.
Results
Staining was positive in 86% of benign areas, 61% of primary cancer specimens, and 12% of lymph node deposits. The preoperative serum prostate-specific antigen level and pathologic stage and grade of the primary tumor did not show any statistically significant correlation with NE staining in any of the areas. Only NE expression in the primary tumor was associated with clinical recurrence, with a 10-year recurrence-free survival rate for those with less than 5% staining of 67% compared with 35% for those with 5% staining or greater (P = 0.03). Furthermore, after adjusting for age, greater NE expression in the primary tumor (relative risk 2.15, P = 0.02) and lymph node deposit (relative risk 2.03, P = 0.03) was associated with poorer overall survival.
Conclusions
NE expression in the primary tumor and lymph node metastasis of patients with node-positive prostate cancer may provide additional prognostic stratification.
aDepartment of Urology, Loyola University Stritch School of Medicine, Maywood, Illinois
bDivision of Urology, Oregon Health and Science University, Portland, Oregon
cDepartment of Pathology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
dDepartment of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, California, USA
fDepartment of Urology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
eDivision of Medical Oncology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
Reprint requests: Jacek Pinski, M.D., Ph.D., Division of Medical Oncology, University of Southern California Keck School of Medicine, Norris Comprehensive Cancer Center, 1441 Eastlake Avenue, Suite 3449, Los Angeles, CA 90033.
ABSTRACT