Johanna Hynninen

FDG PET/CT in staging of advanced epithelial ovarian cancer: Frequency of supradiaphragmatic lymph node metastasis challenges the traditional pattern of disease spread

OBJECTIVE Epithelial ovarian cancer (EOC) spreads intra-abdominally and to the retroperitoneal lymph nodes. A greater number of distant metastases are revealed by (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) compared to conventional imaging methods. We aimed to investigate the presence and anatomic distribution of supradiaphragmatic lymph node metastasis (LNM) detected with pretreatment FDG PET/CT. METHODS Thirty women with advanced stage (IIC-IV) EOC were scanned with whole body contrast-enhanced FDG PET/CT prior to surgery/neoadjuvant chemotherapy. We performed PET/CT analysis qualitatively and quantitatively. Additionally, contrast-enhanced CT was analyzed blinded to PET/CT scan. Intra-abdominal dissemination was verified by surgery and histopathology. Metabolically active lymph nodes were biopsied when possible. The clinical characteristics of patients with and without supradiaphragmatic LNM were compared. RESULTS In 20/30 patients (67%) FDG PET/CT detected supradiaphragmatic LNM in one or more locations, whereas conventional CT found LNM in 10 patients (33%). Fourteen patients had parasternal, 14 cardiophrenic, 8 other mediastinal, 6 axillar, and 1 subclavian LNM. Microscopy of all four biopsied lymph nodes (three axillar and one subclavian) confirmed metastatic dissemination. The patients with supradiaphragmatic LNM had significantly more ascites (p<0.01), higher CA 125 levels, and more frequent subdiaphragmal carcinomatosis (p<0.03) compared to patients without supradiaphragmatic LNM in preoperative FDG PET/CT. CONCLUSIONS A significant number of patients with advanced EOC showed supradiaphragmatic LNM in pre-treatment PET/CT. Our findings suggest that the route of EOC cells from the peritoneal cavity to the lymphatic system permeates the diaphragm mainly to the cardiophrenic and continues to parasternal lymph nodes.

A prospective comparison of integrated FDG-PET/contrast-enhanced CT and contrast-enhanced CT for pretreatment imaging of advanced epithelial ovarian cancer.

OBJECTIVE The use of tumor debulking surgery in the management of epithelial ovarian cancer (EOC), which is often disseminated in the peritoneal cavity at the time of diagnosis, has a significant impact on prognosis. We compared (18)F-fluorodeoxyglucose (FDG) positron emission tomography/contrast-enhanced computed tomography (PET/CT) to contrast-enhanced CT for the detection of dissemination into the abdominal cavity preventing successful primary debulking surgery. METHODS Forty-one women with EOC underwent preoperative whole-body low-dose FDG-PET/CT followed by diagnostic high dose contrast-enhanced CT scan, and the results were compared with systematically recorded surgical findings as a reference standard. Both site-based and patient-based analyses were conducted. RESULTS FDG-PET/CT was superior to conventional CT for the detection of carcinomatosis in subdiaphragmatic peritoneal surfaces (p=0.020) and in the bowel mesentery (p=0.001). Patient-based analysis of upper abdominal areas requiring extensive surgical procedures showed no significant differences between the two imaging methods. The sensitivity of PET/CT and CT was poor in certain areas of the peritoneal cavity (64% vs. 27% in the small bowel mesentery and 65% vs. 55% in the right upper abdomen). Extra-abdominal disease spread was detected by PET/CT in 32 patients and by CT in 25 patients. CONCLUSIONS PET/CT was not superior to CT for the detection of intra-abdominal disease spread. Patients with suspected EOC should be referred for upfront radical surgery regardless of the results of preoperative imaging studies. PET/CT is more effective for the detection of extra-abdominal disease than CT, but the clinical significance of this finding is unclear.

Is perioperative visual estimation of intra-abdominal tumor spread reliable in ovarian cancer surgery after neoadjuvant chemotherapy?

OBJECTIVE Most cases of epithelial ovarian cancer (EOC) are diagnosed in an advanced stage. When the disease has spread intra-abdominally, complete surgical tumor debulking is the single most important prognostic factor. Neoadjuvant chemotherapy (NACT) before surgery can cause fibrosis and adhesions in the peritoneal cavity and may interfere with the perioperative evaluation of tumor spread. In this prospective study, we evaluated whether perioperative visual assessment of tumor dissemination is similar in patients undergoing primary and interval surgery for EOC. METHODS Systematic visual evaluation of tumor spread was performed at the start of primary surgery/diagnostic laparoscopy (n=39) or interval surgery (n=16). Peritoneal cavity was divided into 22 anatomical regions. The carefully documented results of the visual assessment were compared with the histopathological analysis of 220 biopsies from primary and 92 biopsies from interval surgery. RESULTS In primary surgery, perioperative visual estimation of tumor spread showed 98% sensitivity, 76% specificity and 95% accuracy compared to histopathology. The corresponding figures after NACT were 86%, 76% and 84%, respectively. The difference in sensitivity and accuracy in primary and interval operations was statistically significant (p<0.001). CONCLUSIONS In advanced EOC, microscopically carcinomatous areas have a benign visual appearance more often after NACT than at primary surgery. NACT may interfere with the perioperative visual evaluation of tumor spread and thus lead to incomplete resection of tumor in potentially resectable areas.

Serum HE4 Profile During Primary Chemotherapy of Epithelial Ovarian Cancer

Objective Human epididymis protein 4 (HE4) is a promising novel serum biomarker for the detection of early-stage epithelial ovarian cancer (EOC) and for the differential diagnosis between benign and malignant ovarian tumors. The objective of the present study was to determine the value of HE4 for monitoring the response to primary therapy in patients with advanced disease. Methods Serum HE4 and cancer antigen (CA) 125 levels of 10 patients with advanced EOC and one patient with adenocarcinoma of unknown origin were measured preoperatively and during first-line chemotherapy. Seven patients were treated with primary surgery and six cycles of chemotherapy. Response to treatment was evaluated 4 weeks after the completion of chemotherapy using computed tomography. Four patients received neoadjuvant chemotherapy (NACT) before surgery. To evaluate the early response to chemotherapy, changes in serum biomarker levels were compared with metabolic changes of tumors during NACT as detected by positron emission tomography/computed tomography. Results The profile of HE4 during primary chemotherapy was in line with radiologic and clinical responses. In the neoadjuvant chemotherapy group, HE4 correlated better with the radiologic response than CA 125. Conclusion Assessment of serum HE4 may improve the reliability of response evaluation during chemotherapy for serous epithelial ovarian cancer.

18F-FDG-PET/CT can identify histopathological non-responders to platinum-based neoadjuvant chemotherapy in advanced epithelial ovarian cancer.

OBJECTIVE The aim of this study was to examine the relationship between the reduction of maximum standardized uptake values (SUVmax) in 18F-FDG-PET/CT to histopathological changes obtained with neoadjuvant chemotherapy (NACT) in advanced epithelial ovarian cancer (EOC). We wanted to evaluate whether 18F-FDG-PET/CT is useful for identifying patients who will not respond to NACT and would therefore benefit from second-line chemotherapy instead of interval debulking surgery (IDS). METHODS Twenty-six primarily inoperable EOC patients treated with NACT were enrolled in this study. 18F-FDG-PET/CT imaging was performed before diagnostic laparoscopy and after three to four NACT cycles. The relationship between the decrease in omental SUVmax from before to after NACT with omental histopathological response was examined in samples taken from the corresponding anatomical sites during IDS. Patients were divided into three groups according to chemotherapy-induced histopathological changes. Serum CA125 and HE4 halftimes during NACT as well as Ki-67 antigen expression in IDS samples were determined. RESULTS The median omental SUVmax change during NACT was -64% (range-16% to -84%), and it was associated with histopathological response (p=0.004, OR 0.9, CI 0.84-0.97). A SUVmax decrease of less than 57% identified histopathological non-responders. Progression-free survival (PFS) differed between the poor, moderate and good histopathological response groups (0.9 year vs. 1.2 years vs. 1.4 years, respectively, p=0.05). The SUVmax change was not associated with PFS. CONCLUSION 18F-FDG-PET/CT was able to identify patients who would not respond to NACT. To obtain a histopathological response in EOC, a substantial metabolic response in 18F-FDG-PET/CT is necessary.

REG4 Is Highly Expressed in Mucinous Ovarian Cancer: A Potential Novel Serum Biomarker

Preoperative diagnostics of ovarian neoplasms rely on ultrasound imaging and the serum biomarkers CA125 and HE4. However, these markers may be elevated in non-neoplastic conditions and may fail to identify most non-serous epithelial cancer subtypes. The objective of this study was to identify histotype-specific serum biomarkers for mucinous ovarian cancer. The candidate genes with mucinous histotype specific expression profile were identified from publicly available gene-expression databases and further in silico data mining was performed utilizing the MediSapiens database. Candidate biomarker validation was done using qRT-PCR, western blotting and immunohistochemical staining of tumor tissue microarrays. The expression level of the candidate gene in serum was compared to the serum CA125 and HE4 levels in a patient cohort of prospectively collected advanced ovarian cancer. Database searches identified REG4 as a potential biomarker with specificity for the mucinous ovarian cancer subtype. The specific expression within epithelial ovarian tumors was further confirmed by mRNA analysis. Immunohistochemical staining of ovarian tumor tissue arrays showed distinctive cytoplasmic expression pattern only in mucinous carcinomas and suggested differential expression between benign and malignant mucinous neoplasms. Finally, an ELISA based serum biomarker assay demonstrated increased expression only in patients with mucinous ovarian cancer. This study identifies REG4 as a potential serum biomarker for histotype-specific detection of mucinous ovarian cancer and suggests serum REG4 measurement as a non-invasive diagnostic tool for postoperative follow-up of patients with mucinous ovarian cancer.

Postoperative human epididymis protein 4 predicts primary therapy outcome in advanced epithelial ovarian cancer

Primary chemotherapy treatment response monitoring in advanced epithelial ovarian cancer (EOC) is currently based on CT-imaging and serum CA125 values. Serum HE4 profile during first line chemotherapy has not been previously studied. We evaluated the HE4 profile during first line chemotherapy after primary (PDS) and interval debulking surgery (IDS). In total, 49 FIGO stage III/IV EOC patients were included in the study. 22 patients underwent PDS and 27 patients neoadjuvant chemotherapy (NACT) followed by IDS. Serial HE4 and CA125 serum samples were taken during first line chemotherapy. The association of postoperative tumor markers to surgery outcome, primary therapy outcome and progression free survival (PFS) were determined. The lowest HE4 and CA125 values during chemotherapy were compared to primary therapy outcome and PFS. The postoperative HE4 was associated to residual tumor after surgery (p = 0.0001), primary therapy outcome (p = 0.004) and PFS (p = 0.03) in all patients (n = 40). The postoperative CA125 was associated to PFS after IDS (n = 26, p = 0.006), but not after PDS. In multivariate analysis with FIGO stage (III/IV), residual tumor (0/>0) and postoperative CA125, the postoperative HE4 was the only statistically significant prognostic variable predicting PFS. Both HE4 and CA125 nadir corresponded to primary therapy outcome (HE4 p < 0.0001, CA125 p < 0.0001) and PFS (HE4 p = 0.009, CA125 p < 0.0001). HE4 is a promising candidate for EOC response monitoring. In our study, the performance of HE4 in response monitoring of first line chemotherapy was comparable to that of CA125. Of the postoperative values, only HE4 was statistically significantly associated to primary therapy outcome.

Hyper-phosphorylation of Sequestosome-1 Distinguishes Resistance to Cisplatin in Patient Derived High Grade Serous Ovarian Cancer Cells

Platinum-resistance is a major limitation to effective chemotherapy regimens in high-grade serous ovarian cancer (HGSOC). To better understand the mechanisms involved we characterized the proteome and phosphoproteome in cisplatin sensitive and resistant HGSOC primary cells using a mass spectrometry-based proteomic strategy. PCA analysis identified a distinctive phosphoproteomic signature between cisplatin sensitive and resistant cell lines. The most phosphorylated protein in cisplatin resistant cells was sequestosome-1 (p62/SQSTM1). Changes in expression of apoptosis and autophagy related proteins Caspase-3 and SQSTM1, respectively, were validated by Western blot analysis. A significant increase in apoptosis in the presence of cisplatin was observed in only the sensitive cell line while SQSTM1 revealed increased expression in the resistant cell line relative to sensitive cell line. Furthermore, site-specific phosphorylation on 20 amino acid residues of SQSTM1 was detected indicating a hyper-phosphorylation phenotype. This elevated hyper-phosphorylation of SQSTM1 in resistant HGSOC cell lines was validated with Western blot analysis. Immunofluoresence staining of s28-pSQSTM1 showed inducible localization to autophagosomes upon cisplatin treatment in the sensitive cell line while being constitutively expressed to autophagosomes in the resistant cell. Furthermore, SQSTM1 expression was localized in cancer cells of clinical high-grade serous tumors. Here, we propose hyper-phosphorylation of SQSTM1 as a marker and a key proteomic change in cisplatin resistance development in ovarian cancers by activating the autophagy pathway and influencing down-regulation of apoptosis.

Roles of human epididymis protein 4, carbohydrate antigen 125, inhibin B and anti-Müllerian hormone in the differential diagnosis and follow-up of ovarian granulosa cell tumors

OBJECTIVE Evaluation of circulating tumor markers in ovarian cancer is crucial for optimal patient care. The goal of this study was to verify the most accurate circulating tumor markers for the diagnosis and follow-up of adult-type granulosa cell tumors (AGCTs). METHODS The levels of circulating human epididymis protein 4 (HE4) and carbohydrate antigen 125 (CA125), together with AGCT markers inhibin B and anti-Müllerian hormone (AMH), were measured in 135 samples from AGCT patients, 37 epithelial ovarian carcinoma (EOC) patients, and 40 endometrioma (ENDO) patients. The levels were plotted with receiver operating characteristic (ROC) graphs, and the area under the curves (AUC) of the different markers were calculated and compared. RESULTS HE4 levels were significantly lower in AGCTs than in EOCs (p<0.0001). CA125 levels were above 35IU/l in 25% of AGCT patients and 47.5% of ENDO patients, whereas inhibin B and AMH levels were elevated only in patients with AGCTs. In the AUC comparison analyses, inhibin B alone was sufficient to differentiate AGCT from EOC. In differentiating AGCT from ENDO, inhibin B and AMH performed similarly, and the combination of inhibin B and AMH increased the accuracy compared to either marker alone (sensitivity, 100%; specificity, 93%). Among AGCT patients, inhibin B was the best marker for detecting the presence of AGCT. CONCLUSIONS HE4 and CA125 levels were low in AGCTs, and inhibin B was the most accurate circulating biomarker in distinguishing AGCTs from EOCs and from ENDOs. Inhibin B was also the best single marker for AGCT follow-up.

A functional homologous recombination assay predicts primary chemotherapy response and long-term survival in ovarian cancer patients

Purpose: Homologous recombination deficiency (HRD) correlates with platinum sensitivity in patients with ovarian cancer, which clinically is the most useful predictor of sensitivity to PARPi. To date, there are no reliable diagnostic tools to anticipate response to platinum-based chemotherapy, thus we aimed to develop an ex vivo functional HRD detection test that could predict both platinum-sensitivity and patient eligibility to targeted drug treatments. Experimental Design: We obtained a functional HR score by quantifying homologous recombination (HR) repair after ionizing radiation-induced DNA damage in primary ovarian cancer samples (n = 32). Samples clustered in 3 categories: HR-deficient, HR-low, and HR-proficient. We analyzed the HR score association with platinum sensitivity and treatment response, platinum-free interval (PFI) and overall survival (OS), and compared it with other clinical parameters. In parallel, we performed DNA-sequencing of HR genes to assess if functional HRD can be predicted by currently offered genetic screening. Results: Low HR scores predicted primary platinum sensitivity with high statistical significance (P = 0.0103), associated with longer PFI (HR-deficient vs. HR-proficient: 531 vs. 53 days), and significantly correlated with improved OS (HR score <35 vs. ≥35, hazard ratio = 0.08, P = 0.0116). At the genomic level, we identified a few unclear mutations in HR genes and the mutational signature associated with HRD, but, overall, genetic screening failed to predict functional HRD. Conclusions: We developed an ex vivo assay that detects tumor functional HRD and an HR score able to predict platinum sensitivity, which holds the clinically relevant potential to become the routine companion diagnostic in the management of patients with ovarian cancer. Clin Cancer Res; 24(18); 4482–93. ©2018 AACR.