Renal Tumors with Oncocytic and Papillary Features: A Phenotypic and Genotypic Study

The occurrence of kidney oncocytic lesions with an admixed papillary component is not unusual in routine pathology practice. These neoplasms with dual morphology are classically recognized as collision tumors with variable malignant potential. Using immunohistochemistry, we investigated fluorescent in situ hybridization and next generation sequencing of the genetic and phenotypic profiles in the two components of 11 kidney tumors with colliding oncocytic and papillary features. The oncocytic component was CD117 positive, CK7 negative, and AMACR negative; the papillary component was CK7 positive, AMACR positive, and CD117 negative in all cases. Fluorescence in situ hybridization (FISH) results were inconsistent. Next generation sequencing (NGS) analysis demonstrated that the mutations identified in the two tumor components were identical and displayed an allelic frequency of approximately 50%, strongly suspicious for genetic polymorphisms. The two oncocytic and papillary tumor counterparts shared the same genetic profile and did not harbor pathogenic mutations. Clinical confirmation of the biological benign features of these tumors is required. The term collision tumor is not suitable for these neoplasms, and we propose the term oncopapillary tumor for this histological entity.

Reliability of programmed death ligand 1 (PD-L1) tumor proportion score (TPS) on cytological smears in advanced non-small cell lung cancer: a prospective validation study

Introduction:

Programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) assessment is mandatory for the single agent pembrolizumab treatment of patients with advanced non-small cell lung cancer (NSCLC). PD-L1 testing has been validated and is currently certified only on formalin-fixed paraffin-embedded materials but not on cytological smears. Unfortunately, a significant proportion of patients, having only cytological material available, cannot be tested for PD-L1 and treated with pembrolizumab. In this study, we aimed to validate PD-L1 IHC on cytological smears prospectively by comparing clone SP263 staining in 150 paired histological samples and cytological smears of NSCLC patients.

Methods:

We prospectively enrolled 150 consecutive advanced NSCLC patients. The clone SP263 was selected as, in a previous study of our group, it showed higher accuracy compared with clones 28-8 and 22-C3, with good cyto-histological agreement using a cut-off of 50%. For cyto-histological concordance, we calculated the kappa coefficient using two different cut-offs according to the percentage of PD-L1 positive neoplastic cells (<1%, 1–49% and ⩾50%; <50%, ⩾50%).

Results:

The overall agreement between histological samples and cytological smears was moderate (kappa = 0.537). However, when the cyto-histological concordance was calculated using the cut-off of 50%, the agreement was good (kappa = 0.740). With the same cut-off, and assuming as gold-standard the results on formalin-fixed paraffin-embedded materials, PD-L1 evaluation on smears showed specificity and negative predictive values of 98.1% and 93.9%, respectively.

Conclusion:

Cytological smears can be used in routine clinical practice for PD-L1 assessment with a cut-off of 50%, expanding the potential pool of NSCLC patients as candidates for first-line single agent pembrolizumab therapy.

Immunohistochemical over-expression of HER2 does not always match with gene amplification in invasive bladder cancer

BACKGROUND

HER2 is a potential target of therapy in urothelial cancer (UC). Pathological case stratification according to HER2 gene amplification or HER2 protein overexpression was critical for patients' selection in previous unsuccessful clinical trial with HER2 targeting agents.

STUDY DESIGN

We evaluated the HER2 overexpression by immunohistochemistry (IHC) together with the amplification of the HER2 gene with chromogenic(CISH) and fluorescent (FISH) in situ hybridization in a cohort of 61 patients covering the whole spectrum of bladder UC variants, using a tissue microarray (TMA) approach.

RESULTS

IHC was available in all the 61 cases while ISH in 37 and FISH in 42. At IHC, 2/61 cases (3%) were scored 3+; 2 (3%) scored 2+; 2 (3%) scored 1+; the remaining 55 (91%) scored 0. At CISH analysis 10/37 cases (27%) were amplified, 6 cases with HER2 amplification showed positive HER2 IHC (3+, 2+, 1+). Seven cases with IHC score 0 were amplified at CISH. FISH analysis revealed an amplification in 5/42 cases (12%). The total number of HER2amplified cases was different between chromogenic and fluorescent ISH with 5 cases amplified using FISH compared to 10 with CISH.

CONCLUSIONS

In clinical trials with HER2 targeting agents the candidate patients should be investigated not only by IHC but also by ISH, independently of the IHC results. Since also usual type UC can overexpress HER2 we recommend to extend the patients' selection to all the histotypes of bladder cancer other than the micropapillary type.

Similarities and Differences between Clear Cell Tubulo-Papillary and Conventional Clear Cell Renal Cell Carcinoma: A Comparative Phenotypical and Mutational Analysis

Background: Clear cell tubulo-papillary renal cell carcinoma (cctpRCC) is characterized by clear cell morphology, but differs from conventional clear cell carcinoma (ccRCC) for its indolent clinical behavior and genetic background. The differential diagnosis between the two is based on histology and immunohistochemistry (IHC). Methods: We performed a comparative case-control histological, IHC, and genetic analysis by next generation sequencing (NGS), to point out the differences in 10 cases of cctpRCC, and six controls of ccRCC with low stage and grade. Results: All 16 cases showed the IHC profile with cytokeratin 7, racemase, and carbonic anhydrase IX expected for the histological features of each tumor type. By contrast, the NGS mutation analysis that covered 207 amplicons of 50 oncogenes or tumor suppressor genes provided conflicting results. Among the 10 cctpRCC cases, eight (80%) were wild type for all of the genes in the panel, while two (20%) harbored VHL mutations typical of ccRCC. Three of the six (50%) ccRCC control cases showed expected VHL mutations; two (33%) harbored pathogenic mutations in the p53 or the CKIT genes; and one (16%) was wild type. Conclusion: We can assume that histology and ICH are not sufficient for a definitive diagnosis of cctpRCC or ccRCC. Although with a panel covering 50 genes, we found that 80% of cctpRCC were genetically silent; thus, suggesting an indolent biology of these tumors. The differential diagnosis between ccptRCC and ccRCC for the choice of the best therapeutic strategy likely requires the comprehensive evaluation of histology, IHC, and at least VHL mutations.

Paratesticular Mesenchymal Malignancies: A Single-Center Case Series, Clinical Management, and Review of Literature

Background: Primary soft tissue sarcomas arising from the male urinary and genital tract are rare tumors, only accounting for 1% to 2% of all malignancies of the genitourinary tract. Clinical management of advanced disease is lacking in standardized recommendations due to the rarity of the disease. To date, complete and extensive surgery represents the only curative and standardized approach for localized disease, while the impact of retroperitoneal lymphadenectomy and adjuvant treatments on clinical outcomes are still unclear. Similarly, a standardized systemic treatment for advanced metastatic disease is still missing. Cases Presentation: Four out of 274 patients have been identified in our sarcoma population. The mean age was 54 years (range = 45-73). The histotypes showed liposarcoma in 2 cases and leiomyosarcoma in the remaining 2 cases. In all 4 cases, the disease was localized at presentation, patients underwent complete surgery, and no adjuvant treatments were done. Three cases presented a recurrence of disease at a mean follow-up of 86 months (range = 60-106 months), more than 7 years. Two cases were treated with a second surgery and chemotherapy and 1 case only with chemotherapy. Discussion and Conclusions: Sharing data about clinical management of paratesticular mesenchymal tumors is a key issue due to the rarity of this tumor's subtype. In this article, we report the clinical history of 4 patients affected by paratesticular mesenchymal tumor. In particular, main issues of interest are the decision of postoperative treatment and systemic treatment at time of disease recurrence.

Adequacy of endosonography-derived samples from peribronchial or periesophageal intrapulmonary lesions for the molecular profiling of lung cancer

INTRODUCTION AND OBJECTIVES

Endosonography is increasingly used for the diagnosis of centrally located, bronchoscopically invisible intrapulmonary lesions, but data regarding its utility for molecular profiling are lacking. We aimed to assess the suitability of endosonography samples obtained from intrapulmonary lesions for cancer genotyping and programmed-death ligand 1 (PD-L1) testing.

METHODS

A prospectively collected database regarding 99 consecutive patients undergoing endosonography for the diagnosis of an intrapulmonary lesion was retrospectively reviewed. Genotyping ± PD-L1 testing was carried out in the 53 patients with advanced lung cancer and was classified as complete if all clinically indicated tests could be performed, incomplete if at least one test could not be carried out, and unsuccessful if the sample was unsuitable for molecular analysis.

RESULTS

All clinically indicated biomarkers could be tested in 44 (83%) patients, whereas the molecular profiling was classified as incomplete in 6 (11.3%), and unsuccessful in 3 (5.7%). Thirty-seven genetic alterations (KRAS mutation, 17; EGFR mutation, 17; ALK rearrangement, 3) and 2 cases of PD-L1 expression >50% were found in 31 (58%) patients. EGFR was successfully analysed in 94.1% of cases, KRAS in 93.9%, ALK in 89%, ROS1 in 90% and PD-L1 in 63.1%.

CONCLUSION

Endosonography-derived samples from intrapulmonary lesions were suitable for a thorough molecular profiling in most patients. The few cases of incomplete accomplishment of the testing algorithm were related to the failure of PD-L1 analysis due to the exhaustion of the sample or the lack of sufficient tumour cells in the paraffin-embedded material.

MYC Amplification as a Potential Mechanism of Primary Resistance to Crizotinib in ALK-Rearranged Non-Small Cell Lung Cancer: A Brief Report

INTRODUCTION

Translocations of the anaplastic lymphoma kinase (ALK) can be effectively targeted in advanced non-small cell lung cancer by ALK-TKI inhibitors including Crizotinib. However, the development of acquired resistance often limits the duration of these therapies. While several mechanisms of secondary resistance have been already identified, little is known about molecular determinants of primary resistance. In our brief report we investigated the tumor molecular profile of a patient who failed to respond to Crizotinib.

METHODS

Fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS) were run on tumor specimen as well as search and characterization of circulating tumor cells (CTCs) in the blood. Confirmation of clinical findings was achieved using a translational cell-line in vitro model.

RESULTS

We identified the amplification of MYC as a potential new mechanism of primary resistance to ALK inhibition. Human EML4-ALK rearranged cells infected with a lentiviral vector carrying full-length human MYC cDNA were treated in vitro with crizotinib and alectinib. Overexpression of MYC overexpression was associated with a reduced sensitivity to both ALK-inhibitors. MYC-overexpressing clones displayed also increased levels of both cyclin D and E and their growth was reduced by using Cdk4/6 inhibitors such as Palbociclib.

CONCLUSIONS

We postulate that the MYC gene may be implicated in the mechanism of primary resistance to ALK inhibitors. We also suggest potential MYC-directed inhibition strategies to overcome primary resistance in advanced ALK-rearranged NSCLC.

BRCA1 p.His1673del is a pathogenic mutation associated with a predominant ovarian cancer phenotype

We have investigated the clinical significance of the BRCA1 variant p.His1673del in 14 families from the Emilia-Romagna region of Italy, including 20 breast and 23 ovarian cancer cases; four families displayed site-specific ovarian cancer.

The variant, absent in human variation databases, has been reported three times in BRCA1 specific databases; all probands shared the same rare haplotype at the BRCA1 locus, consistent with a common ancestor.

The multifactorial likelihood method by Goldgar, used to estimate the probability of the variant being causative, gave a ratio of 2,263,474:1 in favor of causality. Moreover, in silico modeling suggested that His1673-lacking BRCA1 protein may have a decreased ability to bind BARD1 and other related proteins. All six ovarian carcinomas and two out of four breast carcinomas available showed a loss of the BRCA1 wild-type allele, which in three out of four ovarian carcinomas analyzed by FISH was associated with duplication of the chromosome 17 containing the variant. Although the pathogenicity of the allele is strongly supported by the multifactorial ratio, we cannot exclude that p.His1673del is not itself deleterious, but is linked to another undetected mutation on the same ancestral allele.

Lifelong maintenance of composition, function and cellular/subcellular distribution of proteasomes in human liver

Owing to organ shortage, livers from old donors are increasingly used for transplantation. The function and duration of such transplanted livers are apparently comparable to those from young donors, suggesting that, despite some morphological and structural age-related changes, no major functional changes do occur in liver with age. We tested this hypothesis by performing a comprehensive study on proteasomes, major cell organelles responsible for proteostasis, in liver biopsies from heart-beating donors. Oxidized and poly-ubiquitin conjugated proteins did not accumulate with age and the three major proteasome proteolytic activities were similar in livers from young and old donors. Analysis of proteasomes composition showed an age-related increased of β5i/α4 ratio, suggesting a shift toward proteasomes containing inducible subunits and a decreased content of PA28α subunit, mainly in the cytosol of hepatocytes. Thus our data suggest that, proteasomes activity is well preserved in livers from aged donors, concomitantly with subtle changes in proteasome subunit composition which might reflect the occurrence of a functional remodelling to maintain an efficient proteostasis. Gender differences are emerging and they deserve further investigations owing to the different aging trajectories between men and women. Finally, our data support the safe use of livers from old donors for transplantation.

Molecular alterations in proteasomes of rat liver during aging result in altered proteolytic activities

Aging induces alterations of tissue protein homoeostasis. To investigate one of the major systems catalysing intracellular protein degradation we have purified 20S proteasomes from rat liver of young (2 months) and aged (23 months) animals and separated them into three subpopulations containing different types of intermediate proteasomes with standard- and immuno-subunits. The smallest subpopulation ΙΙΙ and the major subpopulation Ι comprised proteasomes containing immuno-subunits β1i and β5i beside small amounts of standard-subunits, whereas proteasomes of subpopulation ΙΙ contained only β5i beside standard-subunits. In favour of a relative increase of the major subpopulation Ι, subpopulation ΙΙ and ΙΙΙ were reduced for about 55 % and 80 %, respectively, in aged rats. Furthermore, in all three 20S proteasome subpopulations from aged animals standard-active site subunits were replaced by immuno-subunits. Overall, this transformation resulted in a relative increase of immuno-subunit-containing proteasomes, paralleled by reduced activity towards short fluorogenic peptide substrates. However, depending on the substrate their hydrolysing activity of long polypeptide substrates was significantly higher or unchanged. Furthermore, our data revealed an altered MHC class I antigen-processing efficiency of 20S proteasomes from liver of aged rats. We therefore suggest that the age-related intramolecular alteration of hepatic proteasomes modifies its cleavage preferences without a general decrease of its activity. Such modifications could have implications on protein homeostasis as well as on MHC class I antigen presentation as part of the immunosenescence process.

Slug/β-catenin-dependent proinflammatory phenotype in hypoxic breast cancer stem cells

Cancer stem cell survival relies on the activation of inflammatory pathways, which is speculatively triggered by cell autonomous mechanisms or by microenvironmental stimuli. Here, we observed that hypoxic bone marrow stroma-derived transforming growth factor-β 1 promotes the growth of human breast cancer stem cells as mammospheres. The ensuing Slug-dependent serine 139 phosphorylation of the DNA damage sensor H2AX in breast cancer stem cells induces tumor necrosis factor-α and IL-8 mRNAs, whose stability is enhanced by cytoplasmic β-catenin. β-Catenin also up-regulates and binds miR-221, reducing the stability of the miR-221 targets Rad51 and ERα mRNAs. Our data show that the Slug/β-catenin-dependent activation of DNA damage signaling triggered by the hypoxic microenvironment sustains the proinflammatory phenotype of breast cancer stem cells.

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.

Blood and tissue biomarkers in prostate cancer: state of the art

The prevalence of prostate cancer (PCa) is high and increases with age. PCa is the most common cutaneous cancer in American men. Prostate-specific antigen (PSA) screening has impacted the detection of PCa and is directly responsible for a dramatic decrease in stage at diagnosis. Gleason score and stage at the time of diagnosis remain the mainstay to predict prognosis, in the absence of more accurate and reliable tissue or blood biomarkers. Despite extensive research efforts, very few biomarkers of PCa have been introduced to date in clinical practice. Even screening with PSA has recently been questioned. A thorough analysis of all tissue and serum biomarkers in prostate cancer research cannot be easily synthesized, and goes beyond the scope of the present article. Therefore the authors focus here on the most recently reported tissue and circulating biomarkers for PCa whose application in clinical practice is either current or expected in the near future.

Oestrogen receptor 1 mRNA is a prognostic factor in ovarian cancer patients treated with neo-adjuvant chemotherapy: determination by array and kinetic PCR in fresh tissue biopsies

Oestrogen receptors (ESRs) regulate the growth and differentiation of normal ovarian epithelia. However, to date their role as biomarkers in the clinical setting of ovarian cancer remains unclear. In view of potential endocrine treatment options, we tested the role of ESR1 mRNA expression in ovarian cancer in the context of a neo-adjuvant chemotherapy trial. Study participants had epithelial ovarian or peritoneal carcinoma unsuitable for optimal upfront surgery and were treated with neo-adjuvant platinum-based chemotherapy before surgery. RNA was isolated from frozen tumour biopsies before treatment. RNA expression of ESR1 was determined by microarray and reverse transcriptase kinetic PCR technologies. The prognostic value of ESR1 was tested using univariate and multivariate Cox proportional hazards models, Kaplan-Meier survival statistics and the log-rank test. ESR1 positively correlates with proliferation markers and histopathological grading. ESR1 was a significant predictor of survival as a continuous variable in the univariate Cox regression analysis. In multivariate analysis, elevated baseline ESR1 mRNA levels predicted prolonged progression-free survival (P=0.041) and overall survival (P=0.01) after neo-adjuvant chemotherapy, independently of pathological grade and age. We conclude that pretreatment ESR1 mRNA is associated with tumour growth and is a strong prognostic factor in ovarian cancer, independent of the strongest clinical parameters used in clinical routine. We suggest that ESR1 mRNA status should be considered in order to minimize possible confounding effects in ovarian cancer clinical trials, and that early treatment with anti-hormonal agents based on reliable hormone receptor status determination is worth investigating.

Relevance of circulating tumor cells (CTC) in the progression of metastatic breast cancer

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Background: metastatic breast cancer is an incurable disease. Molecular tumor staging methods are required for a better therapeutic approach. Patients and Methods: eight mL blood samples were drawn from 20 patients (pts) (mean age 61.9±9) with metastatic breast cancer at the time of the beginning of a new chemo- or hormonal treatment line. Median follow-up was 7±4.5 months. Twenty- five female healthy blood donor volunteers were used as controls. Blood samples were screened for the presence of circulating tumor cells (CTC) with a quantitative PCR method using molecular probes for human mammaglobin (hMAM) and cytokeratin 19 (CK19). Relative quantification of hMAM and CK19 RNA was obtained using a blood sample infected with known concentrations of MDA-MB453 cells as calibrator. Results: none of the healthy controls was hMAM positive while the cut-off for CK19 was calculated as the mean value of the controls plus two standard deviations. Nine of 20 (45%) pts were hMAM positive, 15/20 (75%) CK19 positive, while 18/20 (90%) pts were positive for at least one marker (CTC positive). Among the 14 (70%) pts who had a disease progression 7 died. Seven of 9 hMAM positive (78%) and 11/15 (73%) CK19 positive pts had disease progression. All the 14 pts who had disease progression were CTC positive while the only 2 CTC negative pts were free from progression at the time of last follow-up. Conclusions: (1) Multiple (hMAM, CK19) rather than single marker detection should be preferred for CTC blood screening in breast cancer. (2) Combined hMAM and CK19 evaluation might identify pts at higher risk of tumor progression and might be useful for stratification and decision making in metastatic breast cancer pts.

No significant financial relationships to disclose.