The best management of patients with brain metastases from an unknown primary tumour is still unclear, as data are scarce and studies are retrospective. We report 33 patients with biopsy-proven brain metastases from a primary tumour not found at the first investigations, who were treated by surgery and/or radiotherapy and followed with serial CT until death. Median survival time for all patients was 10 months and survival rates at 6 months, 1 year and 2 years were 76 %, 42 % and 15 % respectively. Patients with single brain metastasis treated by gross total resection and whole-brain radiotherapy (WBRT) had a median survival of 13 months with 76% alive at 6 months, 57 % at 1 year and 19% at 2 years. Patients with multiple brain metastases who underwent either WBRT alone or WBRT preceded by gross total resection of the symptomatic lesions had a poorer prognosis: median survival of 6-8 months with 50-100% alive at 6 months, 17-20% at 1 year and none alive at 2 years. In 85% of patients with a single brain metastasis a significant improvement in neurological functions was observed after surgical resection; among patients with multiple brain metastases a neurological improvement was observed in all patients who had a resection of symptomatic lesions and only in a half of patients who had WBRT alone. During the follow-up the primary tumour was found in 27/33 patients (82 %) and was located in the lung in 78%. Between 1987 and 1991 (with limited screening for the primary tumour in the follow-up) the unknown tumours were 6/15 (40%); in the more recent period (1992-1996) (CT-based screening for the primary tumour in the follow-up) no primary tumour remained unknown but overall survival has not significantly improved. The number of brain metastases was the only significant factor affecting survival after both univariate and multivariate analysis. This study suggests that, in patients with both single and multiple brain metastases from an undetected primary site when first studied, surgery and/or WBRT enable the control of the brain disease, partly because the systemic disease may be silent for a prolonged time. Only a few asymptomatic patients may benefit from an early detection and treatment of the primary tumour during the follow-up.

It is already well known that hypermethylation of the O6-methylguanine DNA methyltransferase (MGMT) gene promoter is a predictive biomarker of response to temozolomide treatment and of favorable outcomes in terms of overall survival (OS) and progression-free survival (PFS) in glioblastoma (GBM) patients. Nevertheless, MGMT methylation status has not currently been introduced into routine clinical practice, as the choice of the ideal technique and tissue sample specimen is still controversial. The aim of this study was to compare 2 analytical methods, methylation-specific polymerase chain reaction (MSP) and pyrosequencing (PSQ), and their use on 2 different tissue type samples, snap-frozen and formalin-fixed paraffin-embedded (FFPE), obtained from a single-center and uniformly treated cohort of 46 GBM patients. We obtained methylation data from all frozen tissues, while no results were obtained for 5 FFPE samples. The highest concordance for methylation was found on frozen tissues (88.5%, 23/26 samples), using PSQ (76.7%, 23/30 samples). Moreover, we confirmed that OS and PFS for patients carrying methylation of the MGMT promoter were longer than for patients with an unmethylated promoter. In conclusion, we considered MSP a limited technique for FFPE tissues due to the high risk of false-positive results; in contrast, our data indicated PSQ as the most powerful method to stratify methylated/unmethylated patients as it allows reaching quantitative results with high sensitivity and specificity. Furthermore, frozen tumor tissues were shown to be the best specimens for MGMT methylation analysis, due to the low DNA degradation and homogeneity in methylation throughout the tumor.

BACKGROUND The efficacy of second‐line chemotherapy for patients with recurrent or progressive oligodendroglial tumors is limited. In the current study, the authors investigated the use of carboplatin as a second‐line chemotherapeutic agent against these types of tumors. METHODS Twenty‐three patients with recurrent or progressive oligodendrogliomas or oligoastrocytomas after first‐line PCV (procarbazine, lomustine, and vincristine) chemotherapy were enrolled in a single‐institution Phase II study of second‐line carboplatin chemotherapy. All patients had undergone surgery, and most also had undergone conventional radiotherapy. Carboplatin was administered at a dose of 560 mg/m2 intravenously every 4 weeks. Responses were evaluated according to conventional criteria, based on magnetic resonance imaging (MRI) findings. RESULTS Three of 23 patients (13%) had partial responses, with neurologic improvement. Twelve patients (52%) had stable disease; in 2 of these 12 patients, a minor response was seen on MRI. Eight patients (35%) had progressive disease. The median time to tumor progression was 3 months for all patients and 9 months for patients who experienced responses to treatment. Progression‐free survival rates at 6 and 12 months were 34.8% and 8.7%, respectively. Among the salvage treatment plans followed after carboplatin chemotherapy were supportive care alone, radiotherapy, third‐line chemotherapy, and reoperation. The median survival duration from the start of carboplatin administration was 16 months. Myelotoxicity was severe, with Grade 3 or 4 thrombocytopenia in 60% of patients and Grade 3 or 4 neutropenia in 48% of patients. CONCLUSIONS When administered according to a monthly schedule, carboplatin exhibited modest activity in adult patients with recurrent or progressive oligodendroglioma or oligoastrocytoma who experienced treatment failure after PCV chemotherapy; the current treatment regimen also was associated with severe toxicity. Further improvement of second‐line chemotherapy for the patient group examined in the current study is necessary. Cancer 2004;100:807–13. © 2004 American Cancer Society.

Introduction MicroRNAs (miRNAs) are small non-coding RNAs which are known to play an important role in proliferation, differentiation, invasion and angiogenesis of different malignant tumors. The role of tissue and blood level of miRNAs as useful bio-markers of gliomagenesis is also increasing. Interest is growing on tissue and plasma miR-222 level as prognostic marker in first line chemo- and radiotherapy treated patients with glioma, the mechanisms of action and the target genes of this miRNA in gliomagenesis being under extensive investigation. Furthermore, some evidence exist that miR-221 and miR-222 are upregulated in glioblastoma (GBM) patients and that these paralogues target O(6)-methylguanine-DNA methyltransferase (MGMT) mRNA. Here we focused on the prognostic role of tissue miR-222 in GBM patients. Experimental procedures 63 GBM patients were included in the analysis (overall survival (OS) range: 8-122 months). For each patient formalin-fixed paraffin-embedded tissue samples at first surgery were collected. miR-222 expression level was analyzed by qRT-PCR with TaqMan probe, normalizing miR-222 level on miR-U6 level. OS was analyzed by Kaplan-Meyer (K-M) survival curves. MGMT methylation analysis by pyrosequencing on tumoral DNA is on-going. Results In silico analysis of The Cancer Genome Atlas (TCGA) for GBM defined a median OS of 13.6 months in the whole sample population (n=199). Comparison of median OS, done stratifying two groups according to median tissue miR-222 expression level (low 222 vs high 222), showed a significant increased OS in low 222 patients (14.3 vs 13.1 months, p=0.017). Interestingly, K-M curves overlapped for the first 14 months and then diverged after. In particular, K-M analyses starting from 14 months revealed a significantly increased hazard ratio for high 222 patients (HR 1.96, 95% CI = 1.25 - 3.09, p<0.004) in respect to low 222 patients, being the median OS prolonged of further 15.1 months in low 222 and of 6.6 months in high 222 patients. On this basis, we tested the hypothesis of a possible role of miR-222 in a local sample population of 63 GBM patients with prolonged survival. MiR-222 expression level was measured as described above. Therefore, patients were stratified in two groups according to median tissue miR-222 expression level (low 222 vs high 222) and OS analysed on a K-M curve. The Hazard Ratio for high 222 patients was significantly higher (HR=5.30, 95% CI = 2.53-11.11, p<0.0001), being the median OS of 55 month in low 222 vs 30 months in high 222 GBM patients, respectively. Conclusions Quantitative analysis of miR-222 expression in the tumor tissue obtained at first surgery might provide a relevant prediction of prolonged survival in GBM patients. Further conclusions will be presented on the relationship between miR-222 and MGMT which will shed light on a possible role of miR-222 on gene methylation and GBM epigenetics. Citation Format: Laura Lattanzio, Marzia Borgognone, Rossella Merli, M. Cristina Dechecchi, Gianluigi Dorelli, Cristina Mocellini, Andrea Talacchi, Daniela Vivenza, Federica Tonissi, Alessandra Santangelo, Fabrizio Giordano, Caludio Ghimenton, Albino Eccher, Sergio Pericotti, Luisa Zanolla, Claudio Bernucci, Marco Merlano, Cristiana Lo Nigro, Giulio Cabrini. Low miR-222 expression levels predict long-term survival of patients affected by glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4432. doi:10.1158/1538-7445.AM2017-4432