Age-dependent differences in borderline ovarian tumours (BOT) regarding clinical characteristics and outcome: results from a sub-analysis of the Arbeitsgemeinschaft Gynaekologische Onkologie (AGO) ROBOT study

BACKGROUND

Approximately one-third of all borderline ovarian tumours (BOT) are diagnosed in patients with child-bearing potential. Detailed information regarding their specific characteristics and prognostic factors is limited.

METHODS

Clinical parameters of BOT patients treated between 1998 and 2008 in 24 German centres were retrospectively investigated. Central pathology review and prospective follow-up were carried out. Patients <40 versus ≥40 years were analysed separately and then compared regarding clinico-pathological variables and prognosis.

RESULTS

A total of 950 BOT patients with a median age of 49.1 (14.1-91.5) years were analysed [280 patients <40 years (29.5%), 670 patients ≥40 years (70.5%)]. Fertility-preserving surgery was carried out in 53.2% (149 of 280) of patients <40 years with preservation of the primarily affected ovary in 32 of these 149 cases (21.5%). Recurrence was significantly more frequent in patients <40 years (19.0% versus 10.1% 5-year recurrence rate, P < 0.001), usually in ovarian tissue, whereas disease-specific overall survival did not differ between the subgroups. In case of recurrent disease, malignant transformation was less frequent in younger than in older patients (12.0% versus 66.7%, P < 0.001), mostly presenting as invasive peritoneal carcinomatosis. Multivariate analysis for patients <40 years identified advanced International Federation of Gynecology and Obstetrics (FIGO) stage and fertility-sparing approach as independent prognostic factors negatively affecting progression-free survival (PFS) while, for patients ≥40 years, higher FIGO stage and incomplete staging was associated with impaired PFS.

CONCLUSIONS

Despite favourable survival, young BOT patients with child-bearing potential are at higher risk for disease recurrence. However, relapses usually remain BOT in the preserved ovaries as opposed to older patients being at higher risk for malignant transformation in peritoneal or distant localisation. Therefore, fertility-sparing approach can be justified for younger patients after thorough consultation.

Clinical management of borderline ovarian tumors

Borderline ovarian tumors (BOTs) are epithelial tumors of the ovaries characterized by cellular proliferation and nuclear atypia but without an infiltrative growth pattern. As they frequently affect younger patients the clinical management is complicated by considerations such as preserving fertility and reducing postoperative morbidity. Over the past several decades surgical therapy has shifted from a radical approach to more conservative treatment. There are various modes of surgery applied to the patients. All these developments have to be considered from an oncologic standpoint as BOTs represent a potentially malignant disease. Oncologic safety, as well as patients' desires and expectations, have to be balanced to reach the most appropriate treatment for BOTs. For this reason current literature will be discussed in this review to give a thorough overview of this topic and to develop recommendations for the surgical management of these patients. Open questions will be identified to elaborate the need for future surveys and research.

Expression of VEGFR3 in glioma endothelium correlates with tumor grade

Angiogenic processes are regulated by vascular endothelial growth factors (VEGFs) and their receptors VEGFR1 (Flt-1), 2 (Flk-1) and 3 (Flt-4). While VEGFR2 is thought to play a central role in tumor angiogenesis, anti-angiogenic therapies targeting VEGFR2 in glioma models can show escape phenomena with secondary onset of angiogenesis. The purpose of this study was to find explanations for these processes by searching for alternative pathways regulating glioma angiogenesis and reveal a correlation with tumor grade. Thus, VEGFR3, which is not expressed in normal brain, and its ligands VEGF-C and -D, were assessed in high grade (WHO degrees IV, glioblastomas, GBM) and low grade gliomas [WHO degrees II astrocytomas (AII)]. In all GBM, a strong protein expression of VEGFR3 was found on tumor endothelium, VEGF-C and -D expression was found on numerous cells in areas of high vascularization. On RNA level, a significant up-regulation of VEGFR3 was detected in GBM compared to AII and non-neoplastic brain. In AII, only very moderate VEGFR3, VEGF-C and -D expression was found on protein and RNA level indicating a correlation of VEGFR3 expression with tumor grade. VEGFR3 signal in both grades was found predominantly on endothelial cells, confirmed by VEGFR3 expression on isolated CD31 positive cells and the expression of various endothelial markers on VEGFR3-positive cells isolated from GBM. The demonstration of a complete angiogenic signaling system that is dependent on tumor grade may influence the traditional paradigm of glioma angiogenesis and may provide a basis for more effective anti-angiogenic treatment strategies.