Real-World Data and Clinical Implications of Next-Generation Sequencing (NGS)-Based Analysis in Metastatic Breast Cancer Patients.

Over the last two decades, the use of Next-Generation Sequencing (NGS) in medical oncology has increased the likelihood of identifying druggable mutations that may be potentially susceptible to targeted treatments. The European Society for Medical Oncology (ESMO) currently does not recommend the use of the NGS test to determine the therapeutic course of patients with metastatic breast cancer (mBC) in daily clinical practice. However, the aim of this work is to evaluate the potential contribution of the NGS test in selecting targeted therapies for patients with mBC. Data were retrospectively collected from 101 patients diagnosed with metastatic breast cancer and treated at the Modena Cancer Center between January 2015 and April 2022. A NGS test was performed on the tumor tissue of each patient at the Laboratory of Molecular Pathology of the University Hospital of Modena. This study analyzed the clinical-pathological characteristics and mutational profile of the population using NGS tests, with a focus on actionable mutations that could be targeted in advanced stages of clinical development. The indicator of this study was to quantify the actionable mutations that resulted in a change of cancer treatment. In total, 101 patients with metastatic breast cancer were analyzed, including 86 with luminal phenotype, 10 who were HER2-positive and 5 who were triple-negative. Median age was 52 years. NGS analysis was conducted on 47 samples of primary breast cancer, 52 on metastatic sites of disease and 2 on liquid biopsies. A total of 85 gene mutations were found. The most common mutations were identified in the PIK3CA (47%), FGFR (19%) and ERBB2 genes (12%), and to a lesser extent in other genes. Of the 61 patients with pathogenic mutations, 46 (75%) had at least one actionable mutation. Of these, nine received treatment with a molecular target drug: eight patients with a mutation of the PIK3CA gene were treated with alpelisib and fulvestrant; one patient with FGFR1/2 amplifications received TAS120. Median PFS for these patients was 3.8 months. The study results show that using the NGS test on cancer tissue of metastatic breast cancer could influence the therapeutic choices, considering the small sample size and limited follow-up. About 9% of the study population had their therapy modified based on the results of NGS. The growing number of detectable mutations and increased accessibility of the test may lead to a greater number of potential therapeutic implications for the NGS assay. Perspectives suggest that NGS analysis can be implemented in daily clinical practice, particularly in contexts where a Molecular Tumor Board (MTB) is active.

ROS1 pattern of immunostaining in 11 cases of spitzoid tumour: comparison with histopathological, fluorescence in-situ hybridisation and next-generation sequencing analysis.

AIMS: Spitzoid tumours have been shown to harbour exclusive kinase fusions. Few studies have analysed substantial numbers of ROS1-rearranged lesions. The aim of the present study was to investigate also their immunohistochemical profile. METHODS AND RESULTS: Among a group of 35 spitzoid tumours, of which 34 were consecutively diagnosed in a 3-year period, we found 11 ROS1 cases that were immunohistochemically positive, from 10 patients, eight of whom were female and two of whom were male, and who were aged 3-52 years (median, 29 years); most lesions (eight) were localized on the lower extremities. Four patterns of immunostaining were observed: cytoplasmic granular diffuse (six cases), sparse cytoplasmic granules (three cases), paranuclear dots (one case), and nuclear (one case). Fluorescence in-situ hybridisation (FISH) analysis showed all cases to be rearranged (cut-off of >15%). RNA next-generation sequencing (NGS) analysis showed specific fusions of ROS1 in four cases: two with PWWP2A, one with PPFIBP1, and one with ZCCHC8. DNA NGS analysis showed in five cases, specific mutations of AKT, EGFR, NRAS, MYC, ALK, and KIT. ROS1 lesions belonged predominantly to the 'atypical Spitz tumour' group, and showed mainly a nested histological pattern. Interestingly, one patient developed two ROS1-positive lesions. CONCLUSIONS: Immunohistochemistry showed 100% sensitivity and specificity as compared with the FISH results, corresponding to ROS1 rearrangement in 31% of cases studied. These observations shed new light on the value of immunohistochemical evaluation of ROS1 in spitzoid tumours. ROS1 patterns of immunostaining probably reflect different subcellular localisations of ROS1 fusions, although no specific correlations were found in the cases studied. Immunohistochemistry and FISH were the most sensitive techniques for detecting ROS1 rearrangement in this subset of neoplasms.

Deepening the Knowledge of ROS1 Rearrangements in Non-Small Cell Lung Cancer: Diagnosis, Treatment, Resistance and Concomitant Alterations.

ROS proto-oncogene 1 (ROS1) rearrangements are reported in about 1-2% of non-squamous non-small-cell lung cancer (NSCLC). After efficacy of crizotinib was demonstrated, identification of ROS1 translocations in advanced disease became fundamental to give patients the chance of specific and effective treatment. Different methods are available for detection of rearrangements, and probably the real prevalence of ROS1 rearrangements is higher than that reported in literature, as our capacity to detect gene rearrangements is improving. In particular, with next generation sequencing (NGS) techniques, we are currently able to assess multiple genes simultaneously with increasing sensitivity. This is leading to overcome the "single oncogenic driver" paradigm, and in the very near future, the co-existence of multiple drivers will probably emerge more frequently and represent a therapeutic issue. Since recently, crizotinib has been the only available therapy, but today, many other tyrosine kinase inhibitors (TKI) are emerging and seem promising both in first and subsequent lines of treatment. Indeed, novel inhibitors are also able to overcome resistance mutations to crizotinib, hypothesizing a possible sequential strategy also in ROS1-rearranged disease. In this review, we will focus on ROS1 rearrangements, dealing with diagnostic aspects, new therapeutic options, resistance issues and the coexistence of ROS1 translocations with other molecular alterations.

Durable remission in a patient with leptomeningeal relapse of a MYC/BCL6-positive double-hit DLBCL treated with lenalidomide monotherapy.

Secondary central nervous system involvement is an uncommon event that typically occurs early in the natural history of diffuse large B-cell lymphoma and presents as leptomeningeal dissemination in two-thirds of cases. The prognosis of this event is dismal, and treatment options are meagre. Although major validated risk factors for central nervous system dissemination are clinical, concomitant MYC/BCL2 rearrangements as well as MYC/BCL2 protein expression have been recently associated with an increased risk of this complication. Here we present the first case, to our knowledge, of a MYC/BCL6-positive double-hit diffuse large B-cell lymphoma relapsing in the leptomeninges that achieved an outstanding durable remission with single-agent lenalidomide following salvage chemotherapy. Copyright © 2016 John Wiley & Sons, Ltd.

Prospective Biomarker Analysis of the Randomized CHER-LOB Study Evaluating the Dual Anti-HER2 Treatment With Trastuzumab and Lapatinib Plus Chemotherapy as Neoadjuvant Therapy for HER2-Positive Breast Cancer.

BACKGROUND: The CHER-LOB randomized phase II study showed that the combination of lapatinib and trastuzumab plus chemotherapy increases the pathologic complete remission (pCR) rate compared with chemotherapy plus either trastuzumab or lapatinib. A biomarker program was prospectively planned to identify potential predictors of sensitivity to different treatments and to evaluate treatment effect on tumor biomarkers. MATERIALS AND METHODS: Overall, 121 breast cancer patients positive for human epidermal growth factor 2 (HER2) were randomly assigned to neoadjuvant chemotherapy plus trastuzumab, lapatinib, or both trastuzumab and lapatinib. Pre- and post-treatment samples were centrally evaluated for HER2, p95-HER2, phosphorylated AKT (pAKT), phosphatase and tensin homolog, Ki67, apoptosis, and PIK3CA mutations. Fresh-frozen tissue samples were collected for genomic analyses. RESULTS: A mutation in PIK3CA exon 20 or 9 was documented in 20% of cases. Overall, the pCR rates were similar in PIK3CA wild-type and PIK3CA-mutated patients (33.3% vs. 22.7%; p = .323). For patients receiving trastuzumab plus lapatinib, the probability of pCR was higher in PIK3CA wild-type tumors (48.4% vs. 12.5%; p = .06). Ki67, pAKT, and apoptosis measured on the residual disease were significantly reduced from baseline. The degree of Ki67 inhibition was significantly higher in patients receiving the dual anti-HER2 blockade. The integrated analysis of gene expression and copy number data demonstrated that a 50-gene signature specifically predicted the lapatinib-induced pCR. CONCLUSION: PIK3CA mutations seem to identify patients who are less likely to benefit from dual anti-HER2 inhibition. p95-HER2 and markers of phosphoinositide 3-kinase pathway deregulation are not confirmed as markers of different sensitivity to trastuzumab or lapatinib. IMPLICATIONS FOR PRACTICE: HER2 is currently the only validated marker to select breast cancer patients for anti-HER2 treatment; however, it is becoming evident that HER2-positive breast cancer is a heterogeneous disease. In addition, more and more new anti-HER2 treatments are becoming available. There is a need to identify markers of sensitivity to different treatments to move in the direction of treatment personalization. This study identified PIK3CA mutations as a potential predictive marker of resistance to dual anti-HER2 treatment that should be further studied in breast cancer.

Primary cutaneous mantle cell lymphoma of the leg with blastoid morphology and aberrant immunophenotype: a diagnostic challenge.

Mantle cell lymphoma rarely affects the skin and is usually a secondary involvement. The present case illustrates a primary cutaneous mantle cell lymphoma of the leg, with blastoid morphology and aberrant expression of CD10 and bcl-6, which was misinterpreted at the beginning as diffuse large B-cell lymphoma. A larger panel of immunohistochemical markers, including cyclin-D1, and molecular investigation showing the typical translocation (t11;14), pointed toward the correct diagnosis. Cutaneous diffuse B-cell lymphomas with unusual morphology should be interpreted cautiously, and the diagnosis made on the basis of an appropriate panel of antibodies and molecular studies.

Rare Driver Mutations in Advanced, Oncogene-Addicted Non-Small Cell Lung Cancer: A North Italian, Real-World, Registry Experience.

The real-world, retrospective, NEROnE registry investigated the impact of next-generation sequencing (NGS) in advanced non-small-cell lung cancer (NSCLC) patients (pts) at three oncology units in the north of Italy between January 2020 and December 2022. We focused on the clinical characterization and outcomes of NSCLC with rare molecular alterations: EGFR exon 20 insertion, non-activating EGFR mutations, BRAF V600E and non-V600, ROS1 and RET rearrangements, MET, ErbB2, and FGFR mutations. Overall, these represented 6.4% (62/970) of the pts analysed with NGS in the daily practice. The most heavily represented rare alterations were ROS1 rearrangement (15 pts-24%) and MET exon 14 skipping mutation (11 pts-18%). No associations were found with the demographic and clinical features. Forty-nine pts received targeted therapies, of which 38.8% were first- and 9.8% were second-line. The remaining pts received chemotherapy and/or immunotherapy. In terms of the clinical outcomes, although not statistically significant, a tendency toward shorter OS was seen when therapies other than specific targeted therapies were used (HR: 1.84, 95% CI: 0.79-4.33, p = 0.158). The pts with co-mutations (19.4%) seemed to receive an advantage from the front-line chemotherapy-based regimen. Finally, an NLR score (a well-known inflammatory index) ≥ 4 seemed to be related to shorter OS among the pts treated with immunotherapy alone or in combination with chemotherapy (HR: 2.83, 95% CI: 1.08-7.40, p = 0.033). Prospective evaluations need to be performed to clarify whether these indexes may help to identify patients with oncogene-addicted NSCLC who could benefit from immunotherapy.

CtDNA-guided rechallenge with anti-EGFR therapy in RASwt metastatic colorectal cancer: Evidence from clinical practice.

AIM: To apply extended ctDNA-based RAS genotyping to clinical criteria for improving the selection of patients eligible for anti-EGFR-based rechallenge in a real-world setting. METHODS: ctDNA testing was prospectively applied to RASwt mCRC progressed after a first-line anti-EGFR-containing regimen and at least one other line. The primary endpoint was the objective response rate. RESULTS: Among ten enrolled patients, the anti-EGFR rechallenge resulted in an objective response rate and disease control rate of 70% and 90%. The median progression-free survival was 11.3 months and overall survival was not reached. Compared with a historical cohort retreated with anti-EGFR agents based on clinical criteria, the ctDNA-driven approach resulted in a higher chance of achieving an objective response and longer survival. CONCLUSIONS: Blood-based RASwt status may enrich metastatic colorectal cancer more likely to benefit from anti-EGFR-based rechallenge. RAS genotyping in ctDNA represents a feasible, fast, and cost-effective tool to be implemented in the clinic for advancing precision medicine.

Clinicopathological, cytogenetic, and molecular profiles of primary cutaneous diffuse large B-cell lymphomas.

We analyzed the clinicopathological, cytogenetic, and molecular features of 18 primary cutaneous diffuse large B-cell lymphomas (PCDLBCLs) and 15 DLBCLs secondarily localized to the skin (SCDLBCLs), highlighting biological similarities and differences between the 2 groups. PCDLBCLs were subclassified after histopathological review as PCDLBCL-leg type (PCDLBCL-LT, 10 cases) and the PCDLBCL-not otherwise specified (PCDLBCL-NOS, 8 cases). Immunohistochemistry for Hans' algorithm markers, BCL2, and MYC was performed. The molecular study included the determination of the cell of origin (COO) by Lymph2Cx assay on NanoString platform, FISH analysis of IgH, BCL2, BCL6, and MYC genes, as well as the mutation analysis of MYD88 gene. In immunohistochemistry analysis, BCL2 and MYC hyperexpression was more frequent in LT than in NOS cases and, according to Hans' algorithm, PCDLBCL-LTs were mostly of the non-GC type (8/10), whereas in PCDLBCL-NOS, the GC type prevailed (6/8). The determination of COO using Lymph2Cx supported and further confirmed these results. In FISH analysis, all but one LT cases versus 5 of 8 PCDLBCL-NOS showed at least one gene rearrangement among IgH, BCL2, MYC, or BCL6. In addition, MYD88 mutations were more frequently present in LT than in NOS subtypes. Interestingly, MYD88-mutated patients were older, with a non-GC phenotype and had worse OS, compared to MYD88 WT cases. Overall, SCDLBCL did not show, at the genetic and expression level, different profiles than PCDLBCL, even if they bear a significantly worse prognosis. At survival analysis, the most important prognostic factors in patients with PCDLBCL were age and MYD88 mutation, whereas relapse and high Ki-67 expression were relevant in patients with SCDLBCL. Our study comprehensively analyzed the clinicopathological and molecular features of PCDLBCL-LT, PCDLBCL-NOS, and SCDLBCL, underlining the differences among them and the importance of properly identifying these entities at the time of diagnosis.

Proteomic profiling of formalin-fixed paraffine-embedded tissue reveals key proteins related to lung dysfunction in idiopathic pulmonary fibrosis.

Introduction: Idiopathic pulmonary fibrosis (IPF) severely affects the lung leading to aberrant deposition of extracellular matrix and parenchymal stiffness with progressive functional derangement. The limited availability of fresh tissues represents one of the major limitations to study the molecular profiling of IPF lung tissue. The primary aim of this study was to explore the proteomic profiling yield of archived formalin-fixed paraffin-embedded (FFPE) specimens of IPF lung tissues. Methods: We further determined the protein expression according to respiratory functional decline at the time of biopsy. The total proteins isolated from 11 FFPE samples of IPF patients compared to 3 FFPE samples from a non-fibrotic lung defined as controls, were subjected to label-free quantitative proteomic analysis by liquid chromatography-mass spectrometry (LC-MS/MS) and resulted in the detection of about 400 proteins. Results: After the pairwise comparison between controls and IPF, functional enrichment analysis identified differentially expressed proteins that were involved in extracellular matrix signaling pathways, focal adhesion and transforming growth factor ß (TGF-ß) signaling pathways strongly associated with IPF onset and progression. Five proteins were significantly over- expressed in the lung of IPF patients with either advanced disease stage (Stage II) or impaired pulmonary function (FVC<75, DLCO<55) compared to controls; these were lymphocyte cytosolic protein 1 (LCP1), peroxiredoxin-2 (PRDX2), transgelin 2 (TAGLN2), lumican (LUM) and mimecan (OGN) that might play a key role in the fibrogenic processes. Discussion: Our work showed that the analysis of FFPE samples was able to identify key proteins that might be crucial for the IPF pathogenesis. These proteins are correlated with lung carcinogenesis or involved in the immune landscape of lung cancer, thus making possible common mechanisms between lung carcinogenesis and fibrosis progression, two pathological conditions at risk for each other in the real life.

Multicenter Observational Study on Metastatic Non-Small Cell Lung Cancer Harboring BRAF Mutations: Focus on Clinical Characteristics and Treatment Outcome of V600E and Non-V600E Subgroups.

INTRODUCTION: BRAF mutation involved 2-4% of lung adenocarcinoma. Differences in clinicopathologic features and patient outcome exist between V600E and non-V600E BRAF mutated NSCLC. Thus, we sought to assess the frequency and clinical relevance of BRAF mutations in a real-life population of advanced-NSCLC, investigating the potential prognostic significance of distinct genetic alterations. MATERIALS AND METHODS: The present multicenter Italian retrospective study involved advanced BRAF mutant NSCLC. Complete clinicopathologic data were evaluated for BRAF V600E and non-V600E patients. RESULTS: A total of 44 BRAFmut NSCLC patients were included (V600E, n = 23; non-V600E, n = 21). No significant differences in survival outcome and treatment response were documented, according to V600E vs. non-V600E mutations, although a trend towards prolonged PFS was observed in the V600E subgroup (median PFS = 11.3 vs. 6.0 months in non-V600E). In the overall population, ECOG PS and age significantly impacted on OS, while bone lesions were associated with shorter PFS. Compared to immunotherapy, first-line chemotherapy was associated with longer OS in the overall population, and especially in the BRAF V600E subtype. CONCLUSIONS: Here, we report on real-life data from a retrospective cohort of advanced-NSCLC harboring BRAF alterations. Our study offers relevant clues on survival outcome, therapeutic response, and clinicopathologic correlations of BRAF-mutant NSCLC.

Therapeutic Outcomes and Clinical Features of Advanced Non-Small Cell Lung Cancer Carrying KRAS Mutations: A Multicenter Real-life Retrospective Study.

INTRODUCTION: Targeting Kirsten Rat Sarcoma (KRAS) has been deemed impossible for long time, but new drugs have recently demonstrated promising results. Evidence on the outcome of KRAS-mutant advanced-NSCLC treated with new standard regimens are still scarce. Thus, we aimed at assessing the incidence and clinical impact of KRAS mutations in a real-life population of advanced-NSCLC, exploring the prognostic significance of distinct alterations. MATERIALS AND METHODS: The present multicenter retrospective study, conducted by 5 Italian Centers from January 2018 to February 2020, involved 297 advanced KRAS mutant NSCLC. Complete clinico-pathological data were evaluated. RESULTS: Out of 297 patients, 130 carried KRAS_G12C mutation, while 167 presented with mutations other than G12C. Within KRAS_non-G12C group, 73%, 16.8% and 8.9% harboured G12X, codon 13 and Q61H alterations, respectively. No significant differences in survival outcome and treatment response were documented according to KRAS_G12C versus non-G12C, nor KRAS_G12C versus G12X versus other mutations. On univariate analysis ECOG PS, number and sites of metastatic lesions and PD-L1 status significantly impacted on survival. A clear trend towards worse prognosis was apparent in chemotherapy-treated patients, while immunotherapy-based regimens were associated to prolonged survival. Investigating the outcome of PD-L1 ≥ 50% population, we did not detect any significant difference between KRAS_G12C and non-G12C subsets. CONCLUSION: Here, we report on real-life data from a large retrospective cohort of advanced NSCLC harbouring KRAS alterations, with particular attention to G12C mutation. Our study offers useful clues on survival outcome, therapeutic response and clinico-pathological correlations in KRAS-mutant setting, especially in the upcoming era of KRAS G12C targeting therapy.

Cytomegalovirus infection of the upper gastrointestinal tract: a clinical and pathological study of 30 cases.

OBJECTIVE: The study reviews the endoscopic and histological features of human cytomegalovirus (HCMV) infections of the upper gastrointestinal (UGI) tract. MATERIALS AND METHODS: Clinical histories, endoscopic findings and bioptic specimens of 30 cases of HCMV infection of the UGI tract, diagnosed in a University Hospital in a 10-year period, were reviewed. In all cases, viral inclusion bodies were detected in routine histopathological sections and the diagnosis was confirmed with immunohistochemistry. RESULTS: Six patients were HIV+, whereas four had received organ transplantations, one was affected by common variable immunodeficiency and four had a recent history of malignancy. No other pathologic condition was evidenced in the remaining 15 cases. Mucosal alterations were endoscopically observed in the stomach (19 cases), esophagus (9), cardias (6) and duodenum (1), and multiple organs being synchronously affected in five patients (3 HIV+, 2 with history of malignancy). The antropyloric area was the most frequently affected site. Single ulcers were detected in 11 cases and multiple ulcers in 8, whereas mucosal thickenings (in the form of localized thickenings, polyps or rugal hypertrophy) were present in 13 patients. Thickenings of the mucosa were detected only in the stomach. At histology, necrotic material and granulation tissue were associated with moderate or marked lympho-plasmacytic infiltrate and foveolar hyperplasia in ulcerative lesions, whereas lesions labeled as mucosal thickenings showed mild or moderate chronic inflammatory infiltrate and foveolar hyperplasia. CONCLUSIONS: Endoscopic manifestations of UGI tract involvement in HCMV infection are not specific, varying from erythematous mucosa to ulcers to mucosal thickenings.

Atypical Spitzoid melanocytic tumors: a morphological, mutational, and FISH analysis.

BACKGROUND: Identification of the clinical behavior of atypical Spitzoid tumors with conflicting histopathologic features remains controversial. OBJECTIVE: We sought to assess whether molecular findings may be helpful in the diagnostic and prognostic assessment of atypical Spitzoid tumors. METHODS: A total of 38 controversial, atypical Spitzoid lesions (≥ 1 mm in thickness) were analyzed for clinicopathological features, chromosomal alterations by fluorescence in situ hybridization (FISH) analysis (RREB1/MYB/CCND1/CEP6), BRAF(V600E) mutation by allele-specific real-time polymerase chain reaction confirmed by sequencing, and H-RAS gene mutation by direct sequencing. RESULTS: Atypical Spitzoid lesions developed in 21 female and 17 male patients (mean age 22 years). Nine patients underwent sentinel lymph node biopsy and a sentinel lymph node micrometastasis was detected in 4 of these 9 cases. Four additional patients, who did not receive a sentinel lymph node biopsy, experienced bulky lymph node metastases and one experienced visceral metastases and death. Lesions from patients with lymph node involvement showed more deep mitoses (P < .01), less inflammation (P = .05), and more plasma cells (P = .04). FISH analysis demonstrated the presence of chromosomal alterations in 6 of 25 cases. Correlation with follow-up data showed that the only case with fatal outcome showed multiple chromosomal alterations by FISH analysis. BRAF(V600E) mutation was detected in 12 of 16 cases (75%) and H-RAS mutation on exon 3 was found in 3 of 11 cases (27%). LIMITATIONS: Our results require validation in a larger series with longer follow-up information. CONCLUSIONS: FISH assay may be of help in the prognostic evaluation of atypical Spitzoid tumors. Diagnostic significance of BRAF(V600E) and H-RAS mutations in this setting remains unclear.

Alterations of 9p21 analysed by FISH and MLPA distinguish atypical spitzoid melanocytic tumours from conventional Spitz's nevi but do not predict their biological behaviour.

AIM: The aim of this study was to investigate whether 9p21 status influence the prognosis of the spitzoid melanocytic tumours, peculiar lesions whose biological behaviour cannot be predicted by histopathological criteria alone. METHODS AND RESULTS: Twenty-eight atypical spitzoid tumours, 12 conventional Spitz's nevi and one congenital Spitz's nevus were studied by fluorescent in-situ hybridization (FISH) and multiple ligation-dependent probe amplification (MLPA) for the presence of 9p21 deletion. The 28 patients were aged 3-56years (mean 32, median 35), and follow-up ranged between 4 and 156months (mean 51, median 48). Eight patients (28.5%) experienced lymph node metastasis (three cases with macrometastasis and five with micrometastasis). Of those with macrometastasis, two are alive after 159 and 26 months, whereas a third developed widespread metastases and died after 26months. All of the other patients are alive. Statistically, the thickness (P=0.01) and the diameter (P=0.009) of the lesions significantly correlated with metastasis. Deletion of 9p21 by FISH analysis was observed in eight spitzoid tumours (28.5%), and MLPA demonstrated alterations of 9p21, particularly deletion of CDKN2A, in the same lesions, whereas all Spitz's nevi, except the congenital one, were of unaltered 9p21 status (P<0.0001). Deletion of 9p21/CDKN2A did not correlate with the presence of metastasis. CONCLUSION: Alterations at 9p21 locus are significantly more frequent in spitzoid tumours than in Spitz's nevi, but do not predict their biological behaviour.

EGFR polysomy in squamous cell carcinoma of the thyroid. Report of two cases and review of the literature.

AIMS AND BACKGROUND: Primary squamous cell carcinoma of the thyroid gland (PSCCT) is an uncommon malignancy characterized by a poor prognosis. A radical surgical approach combined with radiotherapy or chemotherapy is the generally accepted treatment for this tumor. The epidermal growth factor receptor (EGFR) is a transmembrane tyrosine kinase receptor modulating the cell proliferation and biological progression of many human epithelial tumors. The EGFR overexpression in PSCCT suggests an additional therapeutic option for the treatment of this tumor. METHODS AND STUDY DESIGN: The clinicopathological features and immunohistochemical profiles of two cases of primary squamous cell carcinoma of the thyroid in a 66-year-old and an 83-year-old woman are presented. EGFR status was valued in both cases. RESULTS: Overexpression of EGFR protein was detected in 50% and 75% of the tumor cell membranes. EGRF gene polysomy was detected in both tumors. CONCLUSIONS: Pharmaceuticals targeting EGFR may help to provide the rationale for an additional, novel therapeutic option for this rare tumor, especially when other therapeutic options have been exhausted.

Unexpected tumor response to palliative pelvic radiotherapy in mismatch repair-deficient advanced prostate cancer: a case report.

BACKGROUND: Mismatch-repair-deficiency resulting in microsatellite instability (MSI) may confer increased radiosensitivity in locally advanced/metastatic tumors and thus radiotherapy (RT) potentially might have a changing role in treating this subset of patients, alone or in combination with checkpoint inhibitors. CASE PRESENTATION: We report a 76 year-old Italian male patient presenting with locally advanced undifferentiated prostate cancer (LAPC), infiltrating bladder and rectum. Molecular analysis revealed high-MSI with an altered expression of MSH2 and MSH6 at immunohistochemistry. Two months after 6 chemotherapy cycles with Docetaxel associated to an LHRH analogue, a computed tomography scan showed stable disease. After palliative RT (30 Gy/10 fractions) directed to the tumor mass with a 3D-conformal setup, a follow-up computed tomography scan at 8 weeks revealed an impressive response that remained stable at computed tomography after 9 months, with sustained biochemical response. To our knowledge, this is the first case of such a sustained response to low dose RT alone in high-MSI LAPC. CONCLUSIONS: Routine evaluation of MSI in patients with locally problematic advanced tumors might change treatment strategy and treatment aim in this setting, from a purely palliative approach to a quasi-curative paradigm.

Modulation of Mutational Landscape in HER2-Positive Breast Cancer after Neoadjuvant Chemotherapy.

INTRODUCTION: In early-stage HER2 positive breast cancer (BC) patients, tumor response to neoadjuvant chemotherapy (NACT) predict survival outcomes. Patients achieving less than pathological complete response (pCR) have a worse prognosis, however, this group is heterogeneous. Nowadays limited data on predictive/prognostic biomarkers in patients with residual cancer disease are available. METHODS: Using next-generation sequencing technology, we evaluated a panel of 21 cancer genes in a group of HER2 positive BC patients with residual disease after NACT. A control group of patients who achieved the pCR was selected too. The BC mutational profile was analyzed on both the tumor diagnostic biopsy and matched residual disease. RESULTS: Overall, the detection rate of mutations was 79% in the No-pCR group versus 90% in the pCR cohort and 98% in the residual BC. The most mutated genes were TP53 and PIK3CA. No correlations between single gene mutations and survival outcomes were found. In no-pCR cohort, 52% of patients had different mutational profile after NACT, 69% of them had an increased in the number of mutated genes. Mutational profile changes from diagnostic biopsy to residual BC were a negative prognostic factor in term of relapse free survival: recurrence probability in different gene profile sub-group was 42% vs 0% in the same profile one (P = .019). CONCLUSIONS: Treatment selective pressure on tumor cells due to NACT changed the gene mutational profile in more than half of BC patient with residual tumor disease. Treatment-induced gene mutations significantly increase the risk of relapse. Profiling primary and residual BC is a major step in order to further personalized adjuvant treatment strategy.

Surrogate Molecular Classification of Invasive Breast Carcinoma: A Comparison Between Core Needle Biopsy and Surgical Excision, With and Without Neoadjuvant Therapy.

Surrogate molecular classification identifies different subtypes of invasive breast carcinoma on the basis of their immunohistochemical markers. The purpose of the study is to verify whether the immunohistochemical markers and surrogate molecular subtypes can be correctly assessed on the core needle biopsy (CNB) when compared with the corresponding surgical excision (SE), with or without neoadjuvant treatment (NAT). Cases with invasive carcinomas identified on both CNB and SE were retrospectively selected. With immunohistochemistry for estrogen receptors (ER), progesterone receptors (PgR), Ki67, human epidermal growth factor receptor 2 (Her2), and molecular analysis for Her2, surrogate molecular classification was determined in 4 and 5 groups, according to the 2013 St Gallen consensus. A total of 1067 cases was considered and complete data for surrogate molecular classification were available for 988 cases (655 without NAT, 333 with NAT). Without NAT, concordance was strong for ER and Her2, moderate for PgR, and weak for Ki67; concordance for surrogate molecular classification was moderate. After NAT, lower concordance rates were recorded, with significant reduction of PgR (P<0.001) and Ki67 (P<0.001). Without NAT, the surrogate molecular subtypes of breast carcinoma can be reliably assessed on CNB; Ki67 and/or PgR may be repeated on SE when values are close to cutoffs to avoid tumor subtype misclassification. After NAT, it seems advisable to repeat at least Ki67 and PgR.

Overall survival in patients with lung adenocarcinoma harboring "niche" mutations: an observational study.

Objective: In addition to the most common somatic lung cancer mutations (i. e., KRAS and EGFR mutations), other genes may harbor mutations that could be relevant for lung cancer. We defined BRAF, c-MET, DDR2, HER2, MAP2K1, NRAS, PIK3CA, and RET mutations as "niche" mutations and analyzed. The aim of this retrospective cohort study was to assess the differences in the overall survival (OS) of patients with lung adenocarcinoma harboring niche somatic mutations. Results: Data were gathered for 252 patients. Mutations were observed in all genes studied, except c-MET, DDR2, MAP2K1, and RET. The multivariable analysis showed that 1) niche mutations had a higher mortality than EGFR mutations (HR = 2.3; 95% CI = 1.2-4.4; p = 0.009); 2) KRAS mutations had a higher mortality than EGFR mutations (HR = 2.5; 95% CI = 1.4-4.5; p = 0.003); 3) niche mutations presented a similar mortality to KRAS mutations (HR = 0.9; 95% CI = 0.6-1.5; p = 0.797). Methods: Three cohorts of mutations were selected from patients with lung adenocarcinoma and their OS was compared. Mutations that were searched for, were 1) BRAF, c-MET, DDR2, HER2, MAP2K1, NRAS, PIK3CA, and RET; 2) K-RAS; and 3) EGFR. Differences in OS between these three cohorts were assessed by means of a multivariable Cox model that adjusted for age, sex, smoking habits, clinical stages, and treatments. Conclusions: Niche mutations exhibited an increased risk of death when compared with EGFR mutations and a similar risk of death when compared with KRAS mutations.