***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE In this study we investigated the prognostic value of estrogen receptor α ( ERα ) , ERβ and progesterone receptor ( PR ) expression  in 58 untreated advanced serous ovarian cancer patients . The study also included 12 macroscopically and histopathologically normal ovaries . MATERIAL S AND METHODS Protein expression was evaluated by immunohistochemistry , and antibody staining detected in both the nuclear and cytoplasmic compartments was taken into account . Immunopositivity was analyzed in relation to tumor clinicopathological variables , disease-free survival ( DFS ) , and overall survival ( OS ) . RESULTS Epithelial cells in ovarian cancer tissue showed significantly lower levels of nuclear ERβ and PR , but not ERα , than in normal ovarian tissue . In the case of ERβ , however , while normal ovarian epithelium exhibited almost exclusively strong nuclear staining , ovarian cancer tissue mostly showed cytoplasmic immunopositivity . Nuclear ERα and ERβ expression were not associated with clinical outcome . Conversely , any cytoplasmic ERβ expression was an independent unfavorable prognostic factor for DFS , a finding approaching statistical significance also for OS . These data suggest that , in advanced serous ovarian cancer , cytoplasmic ERβ signaling may be more important for patient survival than its nuclear signaling . In the case of PR , positivity was an independent favorable prognostic factor for DFS . CONCLUSIONS These novel findings , that need to be confirmed in a large prospect i ve trial , suggest that additional prognostic , and possibly therapeutic opportunities may be available in advanced serous ovarian cancer Background Despite a typically good response to first-line combination chemotherapy , the prognosis for patients with advanced ovarian cancer remains poor because of acquired chemoresistance . The use of targeted therapies such as trastuzumab may potentially improve outcomes for patients with ovarian cancer . HER2 overexpression/amplification has been reported in ovarian cancer , but the exact percentage of HER2-positive tumors varies widely in the literature . In this study , HER2 gene status was evaluated in a large , multicentric series of 320 patients with advanced ovarian cancer , including 243 patients enrolled in a multicenter prospect i ve clinical trial of paclitaxel/carboplatin-based chemotherapy .  Methodology /Principal Findings The HER2 status of primary tumors and metastases was evaluated by both immunohistochemistry ( IHC ) and fluorescence in situ hybridization ( FISH ) analysis of paraffin-embedded tissue on conventional slides . The prognostic impact of HER2 expression was analyzed . HER2 gene was overexpressed and amplified in 6.6 % of analyzed tumors . Despite frequent intratumoral heterogeneity , no statistically significant difference was detected between primary tumors and corresponding metastases . Conclusions / Significance Our results show that the decision algorithm usually used in breast cancer ( IHC as a screening test , with equivocal results confirmed by FISH ) is appropriate in ovarian cancer . In contrast to previous series , HER2-positive status did not influence outcome in the present study , possibly due to the fact that patients in our study received paclitaxel/carboplatin-based chemotherapy . This raises the question of whether HER2 status and paclitaxel sensitively are linked 
    Output:
    
In patients with ovarian cancer , elevated level of PR predicted favorable survival , and elevated level of HER2 was associated with worse survival