Bettina Hentschel

Predictive impact of MGMT promoter methylation in glioblastoma of the elderly

O6‐methylguanine‐DNA‐methyltransferase (MGMT) promoter methylation identifies a subpopulation of glioblastoma patients with more favorable prognosis and predicts a benefit from alkylating agent chemotherapy (CT). Little is known about its prevalence and clinical significance in older glioblastoma patients. We studied 233 glioblastoma patients aged 70 years or more (144 males, 89 females, median age: 74 years, range: 70.0–86.6 years), who were prospectively enrolled in the German Glioma Network, for MGMT promoter methylation by methylation‐specific PCR (MSP) in all patients and DNA pyrosequencing in 166 patients. MGMT data were correlated with patient outcome. Median progression‐free survival (PFS) was 4.8 months (95% CI: 4.3–5.3) and median overall survival (OS) was 7.7 months (95% CI: 6.3–9.0). MGMT promoter methylation was detected by MSP in 134 patients (57.5%). For the whole cohort, PFS was 5.2 versus 4.7 months (p = 0.207) and OS was 8.4 versus 6.4 months (p = 0.031) in patients with versus without MGMT promoter methylation. Patients with MGMT methylated tumors had longer PFS when treated with radiotherapy (RT) plus CT or CT alone compared to patients treated with RT alone. Patients with MGMT unmethylated tumors appeared to derive no survival benefit from CT, regardless of whether given at diagnosis together with RT or as a salvage treatment. Patients treated with RT plus CT or CT alone demonstrated longer OS when pyrosequencing revealed >25% MGMT methylated alleles. Taken together, MGMT promoter methylation may be a useful biomarker to stratify elderly glioblastoma patients for treatment with versus without alkylating agent CT.

Promoter methylation and expression of MGMT and the DNA mismatch repair genes MLH1, MSH2, MSH6 and PMS2 in paired primary and recurrent glioblastomas

Epigenetic silencing of the O6‐methylguanine‐DNA methyltransferase (MGMT) gene promoter is associated with prolonged survival in glioblastoma patients treated with temozolomide (TMZ). We investigated whether glioblastoma recurrence is associated with changes in the promoter methylation status and the expression of MGMT and the DNA mismatch repair (MMR) genes MLH1, MSH2, MSH6 and PMS2 in pairs of primary and recurrent glioblastomas of 80 patients, including 64 patients treated with radiotherapy and TMZ after the first operation. Among the primary tumors, the MGMT promoter was methylated in 31 patients and unmethylated in 49 patients. In 71 patients (89%), the MGMT promoter methylation status of the primary tumor was retained at recurrence. MGMT promoter methylation, but not MGMT protein expression, was associated with longer progression‐free survival, overall survival and postrecurrence survival (PRS). Moreover, PRS was increased under salvage chemotherapy. Investigation of primary and recurrent glioblastomas of 43 patients did not identify promoter methylation in any of the four MMR genes. However, recurrent glioblastomas demonstrated significantly lower MSH2, MSH6 and PMS2 protein expression as detected by immunohistochemistry. In conclusion, reduced expression of MMR proteins, but not changes in MGMT promoter methylation, is characteristic of glioblastomas recurring after the current standards of care.

Prognostic or predictive value of MGMT promoter methylation in gliomas depends on IDH1 mutation

Objective: To explore whether the isocitrate dehydrogenase 1 (IDH1) or 1p/19q status determines the prognostic vs predictive role of O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation in the Neuro-Oncology Working Group of the German Cancer Society (NOA)-04 trial anaplastic glioma biomarker cohort. Methods: Patients (n = 183) of the NOA-04 trial with known MGMT and IDH1 status were analyzed for interdependency of the prognostic vs predictive role of MGMT promoter methylation from IDH1 or 1p/19q status and treatment, using progression-free survival (PFS) as an endpoint. An independent validation cohort of the German Glioma Network (n = 75) and the NOA-08 trial (n = 34) served as a confirmation cohort. Results: In tumors with IDH1 mutation, MGMT promoter methylation was associated with prolonged PFS with chemotherapy ± radiotherapy (RT) or RT-only groups, and is thus prognostic. In tumors without IDH1 mutation, MGMT promoter methylation was associated with increased PFS in patients treated with chemotherapy, but not in those who received RT alone as the first-line treatment, and is thus chemotherapy-predictive. In contrast, 1p/19q codeletions showed no such association with the prognostic vs predictive value of MGMT. Conclusions: MGMT promoter methylation is a predictive biomarker for benefit from alkylating agent chemotherapy in patients with IDH1–wild-type, but not IDH1-mutant, malignant gliomas of World Health Organization grades III/IV. Combined IDH1/MGMT assessment may help to individualize clinical decision-making in neuro-oncology.

Total mesometrial resection: high resolution nerve-sparing radical hysterectomy based on developmentally defined surgical anatomy.

Total mesometrial resection (TMMR) is characterized by: i) the en bloc resection of the uterus, proximal vagina, and mesometrium as a developmentally defined entity; ii) transection of the rectouterine dense subperitoneal connective tissue above the level of the exposed inferior hypogastric plexus; and iii) extended pelvic/periaortic lymph node dissection preserving the superior hypogastric plexus. Since July 1998 we have studied prospectively the outcome in patients treated with TMMR for cervical carcinoma FIGO stages IB, IIA, and selected IIB. By July 2002, 71 patients with cervical cancer stages pT1b1 (n = 48), pT1b2 (n = 8), pT2a (n = 3), pT2b (n = 12) had undergone TMMR without adjuvant radiation. Fifty-four percent of the patients exhibited histopathologic high risk factors. At a median observation period of 30 months (9–57 months) two patients relapsed locally, two patients developed pelvic and distant recurrences and two patients only distant recurrences. Three patients died from their disease. Grade 1 and 2 complications occurred in 20 patients, no patient had grade 3 or 4 complications. No severe long-term impairment of pelvic visceral functions related to autonomic nerve damage was detected. Based on these preliminary results, we believe TMMR achieves a promising therapeutic index by providing a high probability of locoregional control at minimal short and long-term morbidity.

Molecular Markers in Low-Grade Gliomas: Predictive or Prognostic?

Purpose: To investigate whether TP53 mutation, 1p/19q codeletions, O6-methylguanylmethyltransferase (MGMT) promoter methylation, and isocitrate dehydrogenase 1 (IDH1) mutation predict natural course of disease or response to radiotherapy or chemotherapy or both in low-grade glioma patients. Experimental Design: Cohort A consisted of 89 patients with diffuse astrocytoma World Health Organization (WHO) grade II (n = 40), oligoastrocytoma (n = 23), or oligodendroglioma (n = 26) who did not receive radiotherapy or chemotherapy after first operation and were monitored until progression [progressive disease (PD); n = 59] and beyond or until the end of follow-up (n = 30). Cohort B consisted of 50 patients with WHO grade II gliomas who received radiotherapy or chemotherapy at diagnosis. Tumors were analyzed for TP53 mutations, 1p/19q codeletions, MGMT promoter methylation, and IDH1 mutations. Results: Median progression-free survival (PFS) in cohort A was 4.1 years (95% CI: 3.1–5.1). No molecular marker was prognostic for PFS after surgery alone, using multivariate adjustment for histology, age, and extent of resection. IDH1 mutations were associated with prolonged survival from the diagnosis of PD in oligoastrocytomas (OA II)/oligodendrogliomas (O II) and with overall survival (OS) in all tumors. 1p/19q codeletion and IDH1 mutation were prognostic for PFS and OS in cohort B. Conclusions: None of the parameters are sensitive prognostic biomarkers in WHO grade II glioma patients who do not receive radiotherapy or chemotherapy after surgery. Limitations of this study include the selection of patients with favorable outcome, the nonrandomized allocation of treatment, and the insufficient sample size to distinguish between effects of radiotherapy versus chemotherapy. Regardless of histology, IDH1 mutation status is the strongest prognostic marker for OS. Clin Cancer Res; 17(13); 4588–99. ©2011 AACR.

Treatment of anaemia in myelodysplastic syndromes with prolonged administration of recombinant human granulocyte colony‐stimulating factor and erythropoietin

Treatment with recombinant human erythropoietin (rhEPO) improves anaemia in ≈ 20% of the patients with myelodysplastic syndromes (MDS). Recent reports suggest that a combination treatment with rhEPO plus recombinant human granulocyte colony‐stimulating factor (rhG‐CSF) given for up to 18 weeks may result in a higher erythroid response rate than with rhEPO alone. We investigated the potential advantage of an even more prolonged schedule of combined rhG‐CSF and rhEPO treatment to obtain and maintain stable responses. In a phase II study, 33 patients with MDS [17 with refractory anaemia (RA), eight with RA with ringed sideroblasts (RARS), eight with RA with excess blasts (RAEB) with bone marrow blast counts less than 20%] were scheduled to receive at least 36 weeks of combined therapy with rhG‐CSF and rhEPO. Seventeen of 28 evaluable patients demonstrated an erythroid response [61%; 95% confidence interval (CI) 41–78] after 12 weeks of treatment. The erythroid response rate was 80% (20 of 25 evaluable patients; 95% CI 59–93) after 36 weeks. Seven of these responses developed between week 12 and week 36, whereas two initially responding patients became refractory. The cytokine therapy was generally well tolerated. Nineteen of the 20 patients responding after 36 weeks continued to be treated with both cytokines. After 1 year and 2 years of continuous combined treatment, 50% of the initially included patients showed a continuing response. Our results suggest that a prolonged combination treatment with rhG‐CSF and rhEPO is highly effective in achieving a stable and long‐lasting erythroid response in many patients with MDS and low blast count.

Molecular classification of diffuse cerebral WHO grade II/III gliomas using genome- and transcriptome-wide profiling improves stratification of prognostically distinct patient groups

Abstract Cerebral gliomas of World Health Organization (WHO) grade II and III represent a major challenge in terms of histological classification and clinical management. Here, we asked whether large-scale genomic and transcriptomic profiling improves the definition of prognostically distinct entities. We performed microarray-based genome- and transcriptome-wide analyses of primary tumor samples from a prospective German Glioma Network cohort of 137 patients with cerebral gliomas, including 61 WHO grade II and 76 WHO grade III tumors. Integrative bioinformatic analyses were employed to define molecular subgroups, which were then related to histology, molecular biomarkers, including isocitrate dehydrogenase 1 or 2 (IDH1/2) mutation, 1p/19q co-deletion and telomerase reverse transcriptase (TERT) promoter mutations, and patient outcome. Genomic profiling identified five distinct glioma groups, including three IDH1/2 mutant and two IDH1/2 wild-type groups. Expression profiling revealed evidence for eight transcriptionally different groups (five IDH1/2 mutant, three IDH1/2 wild type), which were only partially linked to the genomic groups. Correlation of DNA-based molecular stratification with clinical outcome allowed to define three major prognostic groups with characteristic genomic aberrations. The best prognosis was found in patients with IDH1/2 mutant and 1p/19q co-deleted tumors. Patients with IDH1/2 wild-type gliomas and glioblastoma-like genomic alterations, including gain on chromosome arm 7q (+7q), loss on chromosome arm 10q (−10q), TERT promoter mutation and oncogene amplification, displayed the worst outcome. Intermediate survival was seen in patients with IDH1/2 mutant, but 1p/19q intact, mostly astrocytic gliomas, and in patients with IDH1/2 wild-type gliomas lacking the +7q/−10q genotype and TERT promoter mutation. This molecular subgrouping stratified patients into prognostically distinct groups better than histological classification. Addition of gene expression data to this genomic classifier did not further improve prognostic stratification. In summary, DNA-based molecular profiling of WHO grade II and III gliomas distinguishes biologically distinct tumor groups and provides prognostically relevant information beyond histological classification as well as IDH1/2 mutation and 1p/19q co-deletion status.

Gross total but not incomplete resection of glioblastoma prolongs survival in the era of radiochemotherapy

BACKGROUND This prospective multicenter study assessed the prognostic influence of the extent of resection when compared with biopsy only in a contemporary patient population with newly diagnosed glioblastoma. PATIENTS AND METHODS Histology, O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status, and clinical data were centrally analyzed. Survival analyses were carried out with the Kaplan-Meier method. Prognostic factors were assessed with proportional hazard models. RESULTS Of 345 patients, 273 underwent open tumor resection and 72 biopsies; 125 patients had gross total resections (GTRs) and 148, incomplete resections. Surgery-related morbidity was lower after biopsy (1.4% versus 12.1%, P = 0.007). 64.3% of patients received radiotherapy and chemotherapy (RT plus CT), 20.0% RT alone, 4.3% CT alone, and 11.3% best supportive care as an initial treatment. Patients ≤60 years with a Karnofsky performance score (KPS) of ≥90 were more likely to receive RT plus CT (P < 0.01). Median overall survival (OS) (progression free survival; PFS) ranged from 33.2 months (15 months) for patients with MGMT-methylated tumors after GTR and RT plus CT to 3.0 months (2.4 months) for biopsied patients receiving supportive care only. Favorable prognostic factors in multivariate analyses for OS were age ≤60 years [hazard ratio (HR) = 0.52; P < 0.001], preoperative KPS of ≥80 (HR = 0.55; P < 0.001), GTR (HR = 0.60; P = 0.003), MGMT promoter methylation (HR = 0.44; P < 0.001), and RT plus CT (HR = 0.18, P < 0.001); patients undergoing incomplete resection did not better than those receiving biopsy only (HR = 0.85; P = 0.31). CONCLUSIONS The value of incomplete resection remains questionable. If GTR cannot be safely achieved, biopsy only might be used as an alternative surgical strategy.

Long-Term Survival in Primary Glioblastoma With Versus Without Isocitrate Dehydrogenase Mutations

Purpose: The determinants of long-term survival in glioblastoma have remained largely obscure. Isocitrate dehydrogenase (IDH) 1 or 2 mutations are common in World Health Organization (WHO) grades II and III gliomas, but rare in primary glioblastomas, and associated with longer survival. Experimental Design: We compared clinical and molecular characteristics of 69 patients with centrally confirmed glioblastoma and survival >36 months (LTS-36), including 33 patients surviving >60 months (LTS-60), with 257 patients surviving <36 months. MGMT promoter methylation, 1p/19q codeletions, EGFR amplification, TP53 mutations, and IDH1/2 mutations were determined by standard techniques. Results: The rate of IDH1/2 mutations in LTS-36 patients was 34% (23 of 67 patients) as opposed to 4.3% in controls (11 of 257 patients). Long-term survivors with IDH1/2-mutant glioblastomas were younger, had almost no EGFR amplifications, but exhibited more often 1p/19q codeletions and TP53 mutations than LTS patients with IDH1/2 wild-type glioblastomas. Long-term survivors with IDH1/2 wild-type showed no distinguishing features from other patients with IDH1/2 wild-type glioblastomas except for a higher rate of MGMT promoter methylation. Similarly, among 11 patients with IDH1/2-mutant glioblastomas without long-term survival, the only difference to IDH1/2-mutant long-term survivors was less-frequent MGMT promoter methylation. Compared with LTS-36 patients, LTS-60 patients had less frequently TP53 mutations and radiotherapy alone as initial treatment. Conclusions: IDH1/2 mutations define a subgroup of tumors of LTS patients that exhibit molecular characteristics of WHO grade II/III gliomas and secondary glioblastomas. Determinants of LTS with IDH1/2 wild-type glioblastomas, which exhibit typical molecular features of primary glioblastomas, beyond MGMT promoter methylation, remain to be identified. Clin Cancer Res; 19(18); 5146–57. ©2013 AACR.

Detection of micrometastases in pelvic lymph nodes in patients with carcinoma of the cervix uteri using step sectioning: Frequency, topographic distribution and prognostic impact

OBJECTIVES Limited information exist about the frequency of micrometastases, their topographic distribution and prognostic impact in patients with cervical carcinoma (CX). METHODS Lymph nodes of patients with surgically treated CX, FIGO IB to IIB, with pelvic lymph node involvement, were re-examined regarding the size of metastatic deposits, their topographic distribution within the pelvis. Lymph node status (pN0 vs. pN1mic=metastasis<0.2 cm vs. pN1=metastasis>0.2 cm) was correlated to recurrence free (RFS) and overall survival (OS). RESULTS 31.4% of all patients (281/894) represented pelvic lymph node involvement. 22.2.% of the node positive ones showed micrometastases (pN1mic). Most commonly, obturator and internal nodes were affected by pN1mic, without any side differences. Patients with macrometastases (pN1) and micrometastases (pN1mic) represented significant reduced RFS-rate at 5-years (62% [95% CI: 54.2 to 69.8] for pN1 and 68.9% [95% CI: 55.5 to 82.4] for pN1mic) when compared to patients without metastatic disease (91.4% [95% CI: 89.0 to 93.8]; p<0.001) The 5-years OS-rate was decreased in patients with metastatic disease (pN0: 86.6% [95% CI: 83.7 to 89.5], pN1mic: 63.8% [95% CI: 50.9 to 76.7], pN1: 48.2% [95% CI: 40.4 to 56.0]; p<0.0001). These differences persisted in detailed analysis within these subgroups. In multivariate analysis, tumor stage, pelvic lymph node involvement and micrometastases were independent prognostic factors. CONCLUSIONS A remarkable number of patients with CX show micrometastases within pelvic nodes. Micrometastatic disease represents an independent prognostic factor. So, all patients with pelvic lymph node involvement, including micrometastatic deposits, might be candidates for adjuvant treatment.