Stefano Pizzolitto

Brachyury expression in extra-axial skeletal and soft tissue chordomas: A marker that distinguishes chordoma from mixed tumor/myoepithelioma/parachordoma in soft tissue

Axial chordoma represents approximately 1% of malignant bone tumors. This tumor expresses cytokeratins, specifically cytokeratin 19, and commonly S100. More recently brachyury, a transcription factor important in mesodermal differentiation, including notochord development, has been detected by immunohistochemistry in axial chordomas and hemangioblastomas but not chondrosarcomas or other neoplasms. In this report, we describe 10 cases (6 men, 4 women: age 18 to 68u2009y; mean 44.6) of extra-axial tumors, 8 in bone and 2 in soft tissue, with morphologic and immunohistochemical features identical to those of axial chordoma. Imaging excluded metastases from axial chordoma. Three tumors occurred in the tibia, the others in the rib, metatarsal, ulna, femur, pubis: 2 intracortical, 6 intramedullary. Both soft tissue brachyury-positive tumors, one involving the thumb the other the wrist, were sited in the juxta-articular region. Seven of the tumors were widely excised and these patients are disease-free but of the 3 tumors that recurred, 1 was curetted, 1 was marginally excised, and 1 had a pathologic fracture on presentation. Metastases have not occurred in any of the patients. We also confirm the expression of brachyury in hemangioblastomas, and for the first time demonstrates its expression in spermatogonia and testicular germ cell tumors by immunohistochemistry. Brachyury was not detected in a wide range of tumors including carcinomas, lymphomas, and sarcomas. In conclusion, we describe the first series of extra-axial skeletal chordomas bringing the total number of such cases reported in the literature to 11, and present the first report of 2 soft tissue chordomas as defined by brachyury expression.

O6-methylguanine DNA-methyltransferase methylation status can change between first surgery for newly diagnosed glioblastoma and second surgery for recurrence: clinical implications

O(6)-methylguanine DNA-methyltransferase (MGMT) promoter methylation status is a prognostic factor in newly diagnosed glioblastoma patients. However, it is not yet clear whether, and if so how, MGMT methylation status may change. Moreover, it is unknown whether the prognostic role of this epigenetic feature is retained during the disease course. A retrospective analysis was made using a database of 614 glioblastoma patients treated prospectively from January 2000 to August 2008. We evaluated only patients who met the following inclusion criteria: age > or = 18 years; performance status 0-2; histological diagnosis of glioblastoma at both first and second surgery for recurrence; postoperative treatment consisting of: (i) radiotherapy (RT) followed by adjuvant temozolomide (TMZ) until 2005 and (ii) TMZ concurrent with and adjuvant to RT after 2005; a time interval > or = 3 months between first and second surgery. MGMT status was evaluated at first and second surgery in all 44 patients (M:F 32:12, median age: 49 years, range: 27-67 years). In 38 patients (86.4%), MGMT promoter status was assessable at both first and second surgery. MGMT methylation status, changed in 14 patients (37%) of second surgery samples and more frequently in methylated than in unmethylated patients (61.5% vs 24%, P = .03). The median survival was significantly influenced only by MGMT methylation status determined at first surgery (P = .04). Significant changes in MGMT methylation status during the course of GBM occur more frequently in MGMT methylated than unmethylated cases. MGMT methylation status determined at first surgery appears to be of prognostic value; however, it is not predictive of outcome following second surgery.

BRAF and RAS mutations as prognostic factors in metastatic colorectal cancer patients undergoing liver resection

Background:Despite major advances in the management of metastatic colorectal cancer (mCRC) with liver-only involvement, relapse rates are high and reliable prognostic markers are needed.Methods:To assess the prognostic impact of BRAF and RAS mutations in a large series of liver-resected patients, medical records of 3024 mCRC patients were reviewed. Eligible cases undergoing potentially curative liver resection were selected. BRAF and RAS mutational status was tested on primary and/or metastases by means of pyrosequencing and mass spectrometry genotyping assay. Primary endpoint was relapse-free survival (RFS).Results:In the final study population (N=309) BRAF mutant, RAS mutant and all wild-type (wt) patients were 12(4%), 160(52%) and 137(44%), respectively. Median RFS was 5.7, 11.0 and 14.4 months respectively and differed significantly (Log-rank, P=0.043). At multivariate analyses, BRAF mutant had a higher risk of relapse in comparison to all wt (multivariate hazard ratio (HR)=2.31; 95% CI, 1.09–4.87; P=0.029) and to RAS mutant (multivariate HR=2.06; 95% CI, 1.02–4.14; P=0.044). Similar results were obtained in terms of overall survival. Compared with all wt patients, RAS mutant showed a higher risk of death (HR=1.47; 95% CI, 1.05–2.07; P=0.025), but such effect was lost at multivariate analyses.Conclusions:BRAF mutation is associated with an extremely poor median RFS after liver resection and with higher probability of relapse and death. Knowledge of BRAF mutational status may optimise clinical decision making in mCRC patients potentially candidate to hepatic surgery. RAS status as useful marker in this setting might require further studies.

454 next generation-sequencing outperforms allele-specific PCR, Sanger sequencing, and pyrosequencing for routine KRAS mutation analysis of formalin-fixed, paraffin-embedded samples.

Detection of KRAS mutations in archival pathology samples is critical for therapeutic appropriateness of anti-EGFR monoclonal antibodies in colorectal cancer. We compared the sensitivity, specificity, and accuracy of Sanger sequencing, ARMS-Scorpion (TheraScreen®) real-time polymerase chain reaction (PCR), pyrosequencing, chip array hybridization, and 454 next-generation sequencing to assess KRAS codon 12 and 13 mutations in 60 nonconsecutive selected cases of colorectal cancer. Twenty of the 60 cases were detected as wild-type KRAS by all methods with 100% specificity. Among the 40 mutated cases, 13 were discrepant with at least one method. The sensitivity was 85%, 90%, 93%, and 92%, and the accuracy was 90%, 93%, 95%, and 95% for Sanger sequencing, TheraScreen real-time PCR, pyrosequencing, and chip array hybridization, respectively. The main limitation of Sanger sequencing was its low analytical sensitivity, whereas TheraScreen real-time PCR, pyrosequencing, and chip array hybridization showed higher sensitivity but suffered from the limitations of predesigned assays. Concordance between the methods was k = 0.79 for Sanger sequencing and k > 0.85 for the other techniques. Tumor cell enrichment correlated significantly with the abundance of KRAS-mutated deoxyribonucleic acid (DNA), evaluated as ΔCt for TheraScreen real-time PCR (P = 0.03), percentage of mutation for pyrosequencing (P = 0.001), ratio for chip array hybridization (P = 0.003), and percentage of mutation for 454 next-generation sequencing (P = 0.004). Also, 454 next-generation sequencing showed the best cross correlation for quantification of mutation abundance compared with all the other methods (P < 0.001). Our comparison showed the superiority of next-generation sequencing over the other techniques in terms of sensitivity and specificity. Next-generation sequencing will replace Sanger sequencing as the reference technique for diagnostic detection of KRAS mutation in archival tumor tissues.

Glioma-Associated Stem Cells: A Novel Class of Tumor-Supporting Cells Able to Predict Prognosis of Human Low-Grade Gliomas

Background: Translational medicine aims at transferring advances in basic science research into new approaches for diagnosis and treatment of diseases. Low‐grade gliomas (LGG) have a heterogeneous clinical behavior that can be only partially predicted employing current state‐of‐the‐art markers, hindering the decision‐making process. To deepen our comprehension on tumor heterogeneity, we dissected the mechanism of interaction between tumor cells and relevant components of the neoplastic environment, isolating, from LGG and high‐grade gliomas (HGG), proliferating stem cell lines from both the glioma stroma and, where possible, the neoplasm. Methods and Findings: We isolated glioma‐associated stem cells (GASC) from LGG (n=40) and HGG (n=73). GASC showed stem cell features, anchorage‐independent growth, and supported the malignant properties of both A172 cells and human glioma‐stem cells, mainly through the release of exosomes. Finally, starting from GASC obtained from HGG (n=13) and LGG (n=12) we defined a score, based on the expression of 9 GASC surface markers, whose prognostic value was assayed on 40 subsequent LGG‐patients. At the multivariate Cox analysis, the GASC‐based score was the only independent predictor of overall survival and malignant progression free‐survival. Conclusions: The microenvironment of both LGG and HGG hosts non‐tumorigenic multipotent stem cells that can increase in vitro the biological aggressiveness of glioma‐initiating cells through the release of exosomes. The clinical importance of this finding is supported by the strong prognostic value associated with the characteristics of GASC. This patient‐based approach can provide a groundbreaking method to predict prognosis and to exploit novel strategies that target the tumor stroma. Stem Cells 2014;32:1239–1253

Thymidine phosphorylase expression and benefit from capecitabine in patients with advanced breast cancer

BACKGROUND AND AIMnCapecitabine is an orally bioavailable prodrug that is converted to 5-fluorouracil through several enzymatic steps, the last of which is mediated by thymidine phosphorylase (TP). TP has been reported to be expressed at higher levels in cancer tissue compared with normal counterpart. The present study aimed at evaluating the potential relationship between TP expression and benefit from capecitabine in patients with metastatic breast cancer (BC).nnnMETHODSnImmunohistochemistry for TP and other biological markers was carried out on paraffin-embedded cancer tissues of 61 patients with BC treated with at least three cycles of capecitabine as single agent for metastatic disease. All patients had received capecitabine 1000 mg/m(2) b.i.d. days 1-14 every 21 days. The following variables were analyzed as potential determinants of benefit from capecitabine: TP expression, estrogen receptor (ER) and progesterone receptor status, human epidermal growth factor receptor-2 (HER-2) status, MIB-1 expression, performance status at the beginning of capecitabine treatment, stage at diagnosis, grade, presence of visceral metastases at the beginning of capecitabine treatment, and previous chemotherapy.nnnRESULTSnOverall, median time to progression (TTP) was 6.5 months (range 1.4-33). On multivariate analysis, ER status [hazard ratio (HR) for progression = 0.31; 95% confidence interval (CI) = 0.15-0.64; P = 0.002], presence of visceral metastases at the beginning of capecitabine treatment (HR = 2.30; 95% CI = 1.21-4.39; P = 0.01), and capecitabine as first- or second-line treatment (HR = 2.28; 95% CI = 1.21-4.32; P = 0.01) independently predicted TTP. TP was highly expressed in 34 of 61 cases (55.7%). In the subgroup of patients with TP-expressing tumor, TTP was significantly longer in patients who received anthracyclines and taxanes before capecitabine (median TTP 7.5 versus 3.3 months, P = 0.01, log-rank test). Similarly, patients with a TP-positive tumor showed a longer TTP if they received taxanes before capecitabine than patients with TP-positive tumor who did not receive this treatment (7.3 versus 3.4 months, P = 0.03).nnnCONCLUSIONSnThese data provide further evidence that TP expression in BC could represent a biomarker of sensitivity to capecitabine treatment. Prospective studies with translational approach are desirable to confirm the predictive and prognostic role of TP.

Allele Specific Locked Nucleic Acid Quantitative PCR (ASLNAqPCR): An Accurate and Cost-Effective Assay to Diagnose and Quantify KRAS and BRAF Mutation

The use of tyrosine kinase inhibitors (TKIs) requires the testing for hot spot mutations of the molecular effectors downstream the membrane-bound tyrosine kinases since their wild type status is expected for response to TKI therapy. We report a novel assay that we have called Allele Specific Locked Nucleic Acid quantitative PCR (ASLNAqPCR). The assay uses LNA-modified allele specific primers and LNA-modified beacon probes to increase sensitivity, specificity and to accurately quantify mutations. We designed primers specific for codon 12/13 KRAS mutations and BRAF V600E, and validated the assay with 300 routine samples from a variety of sources, including cytology specimens. All were analyzed by ASLNAqPCR and Sanger sequencing. Discordant cases were pyrosequenced. ASLNAqPCR correctly identified BRAF and KRAS mutations in all discordant cases and all had a mutated/wild type DNA ratio below the analytical sensitivity of the Sanger method. ASLNAqPCR was 100% specific with greater accuracy, positive and negative predictive values compared with Sanger sequencing. The analytical sensitivity of ASLNAqPCR is 0.1%, allowing quantification of mutated DNA in small neoplastic cell clones. ASLNAqPCR can be performed in any laboratory with real-time PCR equipment, is very cost-effective and can easily be adapted to detect hot spot mutations in other oncogenes.

Neurosurgical management and postoperative whole-brain radiotherapy for colorectal cancer patients with symptomatic brain metastases.

BackgroundNew systemic treatments for advanced colorectal cancer have conferred a survival advantage, allowing patients to reach a median survival of almost 2xa0years. Due to this remarkable life extension, the incidence of brain metastases, though still low, is progressively increasing over time. There is little reported data on the optimal strategy to manage brain lesions from colorectal cancer.MethodsTo explore the role of an aggressive approach to colorectal cancer brain metastases, we retrospectively collected and analyzed data from 30 patients who underwent neurosurgical resectionxa0+xa0whole-brain radiotherapy between March 1998 and December 2006. Univariate (logrank) and multivariate (Cox’s model) analyses were used to identify prognostic factors.ResultsMedian age at the time of surgery was 66xa0years, median ECOG PS was 1, most patients (87%) had concomitant lung and/or liver metastases. Median number of previous chemotherapies was two, with half of the patients being exposed both to oxaliplatin and irinotecan. A median of 27xa0Gy of radiotherapy were administered to 16 patients after resection. At the time of the analysis, 29 out of 30 patients had died, with a median survival time after brain metastasectomy of 167xa0days (8–682). Only one patient died within a month from surgery. Median survival was significantly longer in patients who received postsurgical radiotherapy (7.6 vs. 4.7 months, Pxa0=xa00.014).ConclusionsNeurosurgical management of symptomatic brain metastases from colorectal cancer is feasible, relatively safe, and offers a chance of prolonged survival. Patients who received radiotherapy after resection experienced a better outcome.

Epithelioid Angiosarcoma of the Skin: A Study of 18 Cases With Emphasis on its Clinicopathologic Spectrum and Unusual Morphologic Features

We report 18 cases of cutaneous angiosarcoma with predominant or exclusive epithelioid morphology. Both sexes were similarly affected. Patients ages ranged from 2 to 97 years, median 77.5 years; 2 were pediatric patients. In elderly patients scalp or facial lesions and cutaneous lesions arising within irradiated breast skin predominated. Limb lesions were seen in younger patients. Microscopically, the tumors were composed of packed polygonal cells with focal evidence of endothelial differentiation. Diverging phenotypes included syncytial growth of large cells with clear nuclei and prominent nucleoli, micronodules of tumor cells scattered in dermis, predominance of discohesive plasmacytoid polygonal cells with abundant bright eosinophilic cytoplasm, sheets of clear cells with coarse granular cytoplasm, trabecular and cord arrangement of tumor cells splaying the dermal collagen, or a pseudoglandular appearance owing to clear cell tubular arrangement with open lumina. These cases posed further diagnostic challenges simulating lymphoma, melanoma, lymphoepithelioma-like carcinoma, adnexal carcinoma, and neuroendocrine carcinoma. Immunohistochemical studies showed positivity for CD31 and CD34; no immunoreactivity was documented for other tested antigens including cytokeratins, S100 protein, melanocytic antigens, leukocyte common antigen, and desmin. Therapeutic modalities included combined local excision, chemotherapy, and radiotherapy, depending on patient clinical status. Of the 9 patients available for follow-up, 5 were alive and apparently well, 2 had recurrent disease, and 2 had died of tumor. Our data show that epithelioid cutaneous angiosarcoma may have a broad morphological spectrum, raising interpretive challenges on microscopy. In addition, its clinical presentation seems to differ in nonelderly patients, with lesions likely related to lymphedema or vascular malformations.

A novel de novo germ‐line V292M mutation in the extracellular region of RET in a patient with phaeochromocytoma and medullary thyroid carcinoma: functional characterization

Contextu2002 In multiple endocrine neoplasia (MEN), rearranged during transfection (RET), gene testing has been extensively exploited to characterize tumour aggressiveness and optimize the diagnostic and clinical management.