Giovanni Tallini

Cytological features of "noninvasive follicular thyroid neoplasm with papillary-like nuclear features" and their correlation with tumor histology

Among thyroid papillary carcinomas (PTCs), the follicular variant is the most common and includes encapsulated forms (EFVPTCs). Noninvasive EFVPTCs have very low risk of recurrence or other adverse events and have been recently proposed to be designated as noninvasive follicular thyroid neoplasm with papillary-like nuclear features or NIFTP, thus eliminating the term carcinoma. This proposal is expected to significantly impact the risk of malignancy associated with the currently used diagnostic categories of thyroid cytology. In this study, we analyzed the fine needle aspiration biopsy (FNAB) cytology features of 96 histologically proven NIFTPs and determined how the main nuclear features of NIFTP correlate between cytological and histological samples. Blind review of FNAB cytology from NIFTP nodules yielded the diagnosis of follicular neoplasm (Bethesda category IV) in 56% of cases, suspicious for malignancy (category V) in 27%, atypia of undetermined significance/follicular lesion of undetermined significance (category III) in 15%, and malignant (category VI) in 2%. We found good correlation (κ=0.62) of nuclear features between histological and cytological specimens. NIFTP nuclear features (size, irregularities of contours, and chromatin clearing) were significantly different from those of benign nodules but not from those of invasive EFVPTC. Our data indicate that most of the NIFTP nodules yield an indeterminate cytological diagnosis in FNAB cytology and nuclear features found in cytology samples are reproducibly identified in corresponding histology samples. Because of the overlapping nuclear features with invasive EFVPTC, NIFTP cannot be reliably diagnosed preoperatively but should be listed in differential diagnosis of all indeterminate categories of thyroid cytology.

Differential Clinicopathological Risk and Prognosis of Major Papillary Thyroid Cancer Variants

CONTEXTnIndividualized management, incorporating papillary thyroid cancer (PTC) variant-specific risk, is conceivably a useful treatment strategy for PTC, which awaits comprehensive data demonstrating differential risks of PTC variants to support.nnnOBJECTIVEnThis study sought to establish the differential clinicopathological risk of major PTC variants: conventional PTC (CPTC), follicular-variant PTC (FVPTC), and tall-cell PTC (TCPTC).nnnMETHODSnThis was a retrospective study of clinicopathological outcomes of 6282 PTC patients (4799 females and 1483 males) from 26 centers and The Cancer Genome Atlas in 14 countries with a median age of 44 years (interquartile range, 33-56 y) and median follow-up time of 37 months (interquartile range, 15-82 mo).nnnRESULTSnThe cohort consisted of 4702 (74.8%) patients with CPTC, 1126 (17.9%) with FVPTC, and 239 (3.8%) with TCPTC. The prevalence of high-risk parameters was significantly different among the three variants, including extrathyroidal invasion, lymph node metastasis, stages III/IV, disease recurrence, mortality, and the use (need) of radioiodine treatment (all P < .001), being highest in TCPTC, lowest in FVPTC, and intermediate in CPTC, following an order of TCPTC > CPTC ≫ FVPTC. Recurrence and mortality in TCPTC, CPTC, and FVPTC were 27.3 and 6.7%, 16.1 and 2.5%, and 9.1 and 0.6%, corresponding to events per 1000 person-years (95% confidence interval [CI]) of 92.47 (64.66-132.26) and 24.61 (12.31-49.21), 34.46 (30.71-38.66), and 5.87 (4.37-7.88), and 24.73 (18.34-33.35) and 1.68 (0.54-5.21), respectively. Mortality hazard ratios of CPTC and TCPTC over FVPTC were 3.44 (95% CI, 1.07-11.11) and 14.96 (95% CI, 3.93-56.89), respectively. Kaplan-Meier survival analyses showed the best prognosis in FVPTC, worst in TCPTC, and intermediate in CPTC in disease recurrence-free probability and disease-specific patient survival. This was particularly the case in patients at least 45 years old.nnnCONCLUSIONnThis large multicenter study demonstrates differential prognostic risks of the three major PTC variants and establishes a unique risk order of TCPTC > CPTC ≫ FVPTC, providing important clinical implications for specific variant-based management of PTC.

THE HISTORY OF THE FOLLICULAR VARIANT OF PAPILLARY THYROID CARCINOMA

ContextnThis review provides historical context to recent developments in the classification of the follicular variant of papillary thyroid carcinoma (FVPTC). The evolution of the diagnostic criteria for papillary thyroid carcinoma is described, clarifying the role of molecular analysis and the impact on patient management.nnnMethodsnA PubMed search using the terms follicular variant and papillary thyroid carcinoma covering the years 1960 to 2016 was performed. Additional references were identified through review of the citations of the retrieved articles.nnnResultsnThe encapsulated/well-demarcated, noninvasive form of FVPTC that occurs annually in 45,000 patients worldwide was thought for 30 years to be a carcinoma. Many studies have shown almost no recurrence in these noninvasive tumors, even in patients treated by surgery alone without radioactive iodine therapy. The categorization of the tumor as outright cancer has led to aggressive forms of treatment, with their side effects, financial costs, and the psychological and social impacts of a cancer diagnosis. Recently, the encapsulated/well-demarcated, noninvasive FVPTC was renamed as noninvasive follicular thyroid neoplasm with papillary-like nuclear features. The new terminology lacks the carcinoma label, enabling clinicians to avoid aggressive therapy.nnnConclusionsnBy understanding the history of FVPTC, future classification of tumors will be greatly improved.

Fully automated PCR detection of KRAS mutations on pancreatic endoscopic ultrasound fine-needle aspirates

Aims In cystic and solid pancreatic lesions, KRAS mutational status refines the diagnosis of uncertain endoscopic ultrasound (EUS) aspirates. This test should have a fast turnaround time and ideally be performed at the centre where the patient is diagnosed. The Idylla KRAS Mutation Test enables standardisation even in units without molecular expertise. Methods The Idylla test was designed for use with formalin-fixed paraffin-embedded (FFPE) sections. However, we directly pipetted 3u2005µL (corresponding to 1/10th of a DNA preparation from the aspirate sample) in the cartridge, which was automatically run as if an FFPE sample had been inserted. The performance was compared with Sanger sequencing, Allele Specific Locked Nucleic Acid PCR (ASLNAqPCR), and 454 Next Generation Sequencing (454-NGS) in light of clinicopathological end points. Results Idylla yielded valid results in 49/52 (94.2%) cases, in 2u2005h. A total of 18/49 cases showed mutation either in KRAS exon 2 (14/18) or in exon 3 (4/18). Idylla KRAS test had 100% specificity and a sensitivity (55.1%) higher than Sanger sequencing (41.3%) and identical to ASLNAqPCR (55.1%). When the low-abundant mutant allele (<5%) cases were excluded from the analysis, the Idylla KRAS Mutation Test clinical sensitivity increased to 61.9% approaching that of 454-NGS (66.6%). Conclusions This is the first study that applied the novel Idylla KRAS test to the clinical setting of pancreatic cancer. In particular, this system can be easily implemented in the routine assessment of pancreatic EUS-fine-needle aspiration-derived DNA samples to quickly provide information on KRAS mutational status to supplement cytological evaluation.

Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features: Historical Context, Diagnosis, and Future Challenges

The encapsulated/well-demarcated non-invasive form of follicular variant of papillary thyroid carcinoma (FVPTC) that occurs annually in 45,000 patients worldwide was thought for 30xa0years to be a carcinoma. Many studies have now shown almost no recurrence in these non-invasive tumors, even in patients treated by surgery without radioactive iodine therapy. The categorization of the tumor as cancer has led to aggressive forms of treatment, with their side effects, financial costs, and the psychological and social impact of a cancer diagnosis. Recently, the encapsulated/well-demarcated non-invasive, FVPTC was renamed as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) by an international group of experts. The new terminology lacks the carcinoma label enabling clinicians to avoid aggressive therapy. By taking the reader through the history of FVPTC, this article explains how diagnostic criteria for thyroid carcinoma of follicular cells have evolved over the last 60xa0years. It discusses the steps that led to the labeling of FVPTC as cancer and highlights the various studies that helped reclassify and rename this tumor. It also sheds light on the impact of this reclassification on cytologic diagnosis and focuses on the studies needed to refine and expand the histologic criteria of NIFTP. By understanding the history of this change in nomenclature, future classification of tumors will be greatly improved.

Molecular profiles of cancer stem-like cell populations in aggressive thyroid cancers

A substantial proportion of patients with advanced thyroid carcinoma fail to respond to or at some point become refractory to conventional therapies. This resistance and the phenomena of thyroid cancer progression and metastasis themselves are thought to be related to tumor-cell sub-populations with stem-like properties. We isolated thyrospheres from four advanced thyroid carcinomas that were resistant to radioiodine therapy and analyzed their molecular profiles. ALDH activity and proteomic profile of main stem cell markers were used to assess stem cell properties. The TaqMan Low Density Array approach was used to evaluate the expression of several genes involved in the EMT process. The phosphorylation status of tyrosine kinase receptors (RTKs) was analyzed to identify potential markers for targeted therapies. We then investigated the effects of the EMT-inhibitor crizotinib on both cell proliferation and phosphorylation status of RTK targets. The cancer stem-like properties of a subset of cells from primary cultures of each tumor were demonstrated. A wide variability among thyrospheres arising from the four thyroid cancers in terms of ALDH activity, stem cell marker expression, and phosphoproteome profiling was present. Dysregulated expression of genes involved in the EMT was observed in all four thyrosphere lines. Treatment with crizotinib was ineffective in cancer stem-like cells, suggesting the presence of a mechanism of resistance in thyrospheres. Collectively, our data indicate that thyroid cancer stem-like populations vary markedly from tumor to tumor and require detailed molecular and biological characterization if they are to be used as the basis of “personalized” treatment of aggressive disease.

Role of MGMT Methylation Status at Time of Diagnosis and Recurrence for Patients with Glioblastoma: Clinical Implications

BACKGROUNDnMGMT methylation status represents a powerful prognostic factor in newly diagnosed glioblastoma (GBM). Recently, its role in recurrent tumors has also been suggested; however, few data investigating the stability of this biomarker during the clinical course of the disease are available. In this study, we evaluated the rate of change of MGMT methylation status between diagnosis and first recurrence in patients who received tumor resection for recurrent GBM.nnnMETHODSnWe included patients who received temozolomide concurrent with and adjuvant to radiotherapy after diagnosis of GBM and had a second surgery performed at least 3 months after radiotherapy completion. Other eligibility criteria were age ≥18 years and Eastern Cooperative Oncology Group performance status 0-2. We evaluated the MGMT methylation status by methylation-specific polymerase chain reaction.nnnRESULTSnFrom our institutional data warehouse, 295 patients with recurrent GBM who underwent second surgery were evaluated. MGMT methylation status at both first and second surgery was available for 108 patients. MGMT was methylated in both surgeries in 38 patients (35.2%), while it was unmethylated in 43 patients (39.8%). We found a significant concordance between the first and the second MGMT methylation assessments (Ku2009=u20090.500, pu2009<u2009.001), MGMT methylation being stable in 75% of the cases.nnnCONCLUSIONnMGMT methylation presents relative stability during the clinical course of GBM. The Oncologist 2017;22:432-437 IMPLICATIONS FOR PRACTICE: MGMT methylation is a prognostic factor in newly diagnosed glioblastoma. In this study, we evaluated the rate of change of MGMT methylation during the clinical course of the disease, and we found a significant concordance between the first and the second MGMT methylation assessments, with MGMT methylation being stable in 75% of the cases. Thus, re-testing this biomarker at recurrence does not provide further information for clinicians. MGMT methylation at first surgery, extent of resection at second surgery, and time between first and second surgery are significantly correlated with overall survival. Age and extent of resection are correlated with post-progression survival.

The percentage of Epidermal Growth Factor Receptor (EGFR)-mutated neoplastic cells correlates to response to tyrosine kinase inhibitors in lung adenocarcinoma

Background Epidermal Growth Factor Receptor (EGFR) molecular analysis is performed to assess the responsiveness to Tyrosine Kinase Inhibitors (TKIs) in patients with Non-Small Cell Lung Cancer (NSCLC). The existence of molecular intra-tumoral heterogeneity has been observed in lung cancers. The aim of the present study is to investigate if the percentage of mutated neoplastic cells within the tumor sample might influence the responsiveness to TKIs treatment. Material and methods A total of 931 cases of NSCLC were analyzed for EGFR mutational status (exon 18, 19, 20, 21) using Next Generation Sequencer. The percentage of mutated neoplastic cells was calculated after normalizing the percentage of mutated alleles obtained after next generation sequencer analysis with the percentage of neoplastic cells in each tumor. Results Next generation sequencing revealed an EGFR mutation in 167 samples (17.9%), mainly deletions in exon 19. In 18 patients treated with TKIs and with available follow-up, there was a significant correlation between the percentage of mutated neoplastic cells and the clinical response (P = 0.017). Patients with a percentage of mutated neoplastic cells greater than 56%, have a statistical trend (P = 0.081) for higher Overall Survival (26.3 months) when compared to those with a rate of mutated neoplastic cells lower than 56% (8.2 months). Conclusions The percentage of EGFR-mutated neoplastic cells in the tumor is associated with response to TKIs. A “quantitative result” of EGFR mutational status might provide useful information in order to recognize those patients which might have the greatest benefit from TKIs.

Histopathologic Modification in CNS Neuroectodermal Tumor: A Long Term Follow Up of a Clinical Case

Background: Post-therapy differentiation in medulloblastoma (MB) is a rare event that has been described only in pediatric age. nMethods: We describe the long term follow up of a case of medulloblastoma maturation after chemotherapy and radiotherapy in an adult MB patient. nResults and Discussion: A 20-year-old patient was partially resected of a MB with ki-67 of 60%. DNA methylation-derived subgroup showed a molecular SHH profile. The patient received cranio-spinal tomotherapy (32.4 Gy in 18 fractions) with a boost on posterior fossa (23.4 Gy in 17 fractions, total dose: 55.8 Gy in 32 fractions). The MRI performed 2 months after revealed a minimal volumetric increase. The patient underwent 2 cycles of Cisplatin - Etoposide chemotherapy. The MRI showed stable disease. The patient underwent second surgery. The specimen showed neuronal cells showing various degrees of maturation from neurocytic to ganglion cells. No embryonal cells were present. Mitoses were absent. The residual lesion showed the post-therapy neuronal maturation of a medulloblastoma. DNA methylation-derived subgrouping confirmed the SHH profile. No other treatments were delivered after the second resection. To date the patient is still alive and free from progression 54 months after primary surgery. nConclusion: After a long term follow up, we showed that tumor maturation in an adult patient with medulloblastoma is characterized by a favorable outcome. Physicians should take into account that tumor maturation may occur and that its recognition is essential to define the prognosis and to manage adult patients.

Relationship among clinical, pathological and bio-molecular features in low-grade epilepsy-associated neuroepithelial tumors

The aim of this study was to evaluate the relationship between molecular markers and clinicopathological features in patients operated on for low-grade epilepsy-associated neuroepithelial tumors. Molecular-genetic signatures are becoming increasingly important in characterizing these lesions, which represent the second most common cause of focal epilepsy in patients undergoing epilepsy surgery. Data from 22 patients operated on for histopathologically confirmed low-grade epilepsy-associated neuroepithelial tumors were retrospectively collected. All specimens were examined for BRAF and IDH mutational status, 1p/19q codeletion and CD34 expression. The relationship between bio-molecular markers and several demographic, clinical and pathological features were analyzed. BRAF mutation was found in 11 (50.0%) patients and CD34 expression in 13 (59.1%). No patients presented IDH mutation or 1p/19q codeletion. Multiple seizure types were present in 5 (45.5%) patients with BRAF mutation and in none of those with BRAF wild type (p=0.035). Moreover, BRAF mutation was predominant in right-sided lesions (p=0.004) and CD34 expression was significantly associated with a longer duration of epilepsy (p=0.027). Several other clinicopathological features, such as association with focal cortical dysplasia and postoperative seizure outcome, showed no significant correlation with molecular markers. Further studies are necessary both to confirm these data in larger cohort of patients and to investigate possible relationships between molecular markers and other clinicopathological features.