Deborah Smith1, Colin J R Stewart2, Edward M Clarke3, Felicity Lose3, Claire Davies1, Jane Armes1, Andreas Obermair4, Donal Brennan5, Penelope M Webb6, Christina M Nagle6, Amanda B Spurdle7. 1. Department of Pathology, The Mater Hospital, Brisbane, Queensland, Australia. 2. Department of Histopathology, King Edward Memorial Hospital, Perth, WA, Australia; School for Woman's and Infants' Health, University of Western Australia, Perth, WA, Australia. 3. Population Health Department QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia. 4. School of Medicine, The University of Queensland, QLD, Australia; Queensland Centre for Gynaecological Cancer, Brisbane, QLD, Australia. 5. Queensland Centre for Gynaecological Oncology, University of Queensland, School of Medicine, Central Clinical Division, Brisbane, Australia. 6. Population Health Department QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia; The University of Queensland, School of Public Health, Brisbane, Australia. 7. Population Health Department QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia. Electronic address: amanda.spurdle@qimrberghofer.edu.au.
Abstract
OBJECTIVE: To measure association between endometrial carcinoma ER and PR status and endometrial cancer (EC) survival, accounting for inter-observer variation. METHODS: The intensity and proportion of tumor cell expression of ER and PR in ECs were assessed independently and semi-quantitatively by two pathologists using digital images of duplicate tumor tissue microarrays (TMAs). Cases with inconsistent initial assessment were reviewed and final scoring agreed. The association between overall and EC-specific survival and hormone receptor expression (intensity, proportion and combined) was assessed using Cox regression analysis. The C-index was used to evaluate model discrimination with addition of ER and PR status. RESULTS: Tumor ER and PR analysis was possible in 659 TMAs from 255 patients, and in 459 TMAs from 243 patients, respectively. Initial ER and PR scoring was consistent in 82% and 80% of cases, respectively. In multivariate analyses decreased ER and PR expression was associated with increased tumor-related mortality. Associations reached statistical significance for ER proportion score (P=0.05), ER intensity score (P=0.003), and PR combined score (P=0.04). Decreased expression of combined ER/PR expression was associated with poorer EC-specific survival than decreased expression of either hormone receptor alone (P=0.005). However, hormone receptor status did not significantly improve mortality prediction in individual cases. CONCLUSION: ER and PR expression combined, using cut-points that capture variation in scoring and across cores, is significantly associated with EC-specific survival in analyses adjusting for known prognostic factors. However, at the individual level, ER and PR expression does not improve mortality prediction.
OBJECTIVE: To measure association between endometrial carcinoma ER and PR status and endometrial cancer (EC) survival, accounting for inter-observer variation. METHODS: The intensity and proportion of tumor cell expression of ER and PR in ECs were assessed independently and semi-quantitatively by two pathologists using digital images of duplicate tumor tissue microarrays (TMAs). Cases with inconsistent initial assessment were reviewed and final scoring agreed. The association between overall and EC-specific survival and hormone receptor expression (intensity, proportion and combined) was assessed using Cox regression analysis. The C-index was used to evaluate model discrimination with addition of ER and PR status. RESULTS:Tumor ER and PR analysis was possible in 659 TMAs from 255 patients, and in 459 TMAs from 243 patients, respectively. Initial ER and PR scoring was consistent in 82% and 80% of cases, respectively. In multivariate analyses decreased ER and PR expression was associated with increased tumor-related mortality. Associations reached statistical significance for ER proportion score (P=0.05), ER intensity score (P=0.003), and PR combined score (P=0.04). Decreased expression of combined ER/PR expression was associated with poorer EC-specific survival than decreased expression of either hormone receptor alone (P=0.005). However, hormone receptor status did not significantly improve mortality prediction in individual cases. CONCLUSION: ER and PR expression combined, using cut-points that capture variation in scoring and across cores, is significantly associated with EC-specific survival in analyses adjusting for known prognostic factors. However, at the individual level, ER and PR expression does not improve mortality prediction.