The Impact of Next-generation Sequencing on Interobserver Agreement and Diagnostic Accuracy of Desmoplastic Melanocytic Neoplasms

Next-generation sequencing (NGS) is increasingly being utilized as an ancillary tool for diagnostically challenging melanocytic neoplasms. It is incumbent upon the pathology community to perform studies assessing the benefits and limitations of these tools in specific diagnostic scenarios. One of the most challenging diagnostic scenarios faced by skin pathologists involves accurate diagnosis of desmoplastic melanocytic neoplasms (DMNs). In this study, 20 expert melanoma pathologists rendered a diagnosis on 47 DMNs based on hematoxylin and eosin sections with demographic information. After submitting their diagnosis, the experts were given the same cases, but this time with comprehensive genomic sequencing results, and asked to render a diagnosis again. Identification of desmoplastic melanoma (DM) improved by 7%, and this difference was statistically significant ( P <0.05). In addition, among the 15 melanoma cases, in the pregenomic assessment, only 12 were favored to be DM by the experts, while after genomics, this improved to 14 of the cases being favored to be DM. In fact, some cases resulting in metastatic disease had a substantial increase in the number of experts recognizing them as DM after genomics. The impact of the genomic findings was less dramatic among benign and intermediate-grade desmoplastic tumors (BIDTs). Interobserver agreement also improved, with the Fleiss multirater Kappa being 0.36 before genomics to 0.4 after genomics. NGS has the potential to improve diagnostic accuracy in the assessment of desmoplastic melanocytic tumors. The degree of improvement will be most substantial among pathologists with some background and experience in bioinformatics and melanoma genetics.

Lag-3 expression and clinical outcomes in metastatic melanoma patients treated with combination anti-lag-3 + anti-PD-1-based immunotherapies

Lymphocyte-activation gene-3 (LAG-3), an immune checkpoint receptor, negatively regulates T-cell function and facilitates immune escape of tumors. Dual inhibition of LAG-3 and programmed cell death receptor-1 (PD-1) significantly improved progression-free survival (PFS) in metastatic melanoma patients compared to anti-PD-1 therapy alone. Investigating the utility of LAG-3 expression as a biomarker of response to anti-LAG-3 + anti-PD-1 immunotherapy is of great clinical relevance. This study sought to evaluate the association between baseline LAG-3 expression and clinical outcomes following anti-LAG-3 and anti-PD-1-based immunotherapy in metastatic melanoma. LAG-3 immunohistochemistry (clone D2G4O) was performed on pre-treatment formalin-fixed, paraffin-embedded metastatic melanoma specimens from 53 patients treated with combination anti-LAG-3 + anti-PD-1-based therapies. Eleven patients had received prior anti-PD-1-based treatment. Patients were categorized as responders (complete/partial response; n = 36) or non-responders (stable/progressive disease; n = 17) based on the Response Evaluation Criteria in Solid Tumours (RECIST). Tumor-infiltrating lymphocytes (TILs) were scored on hematoxylin and eosin-stained sections. LAG-3 expression was observed in 81% of patients, with staining in TILs and dendritic cells. Responders displayed significantly higher proportions of LAG-3+ cells compared to non-responders (P = .0210). LAG-3 expression positively correlated with TIL score (P < .01). There were no significant differences in LAG-3 expression between different sites of metastases (P > .05). Patients with ≥ 1% LAG-3+ cells in their tumors had significantly longer PFS compared to patients with < 1% LAG-3 expression (P = .0037). No significant difference was observed in overall survival between the two groups (P = .1417). Therefore, the assessment of LAG-3 expression via IHC warrants further evaluation to determine its role as a predictive marker of response and survival in metastatic melanoma.

Cross-platform comparison of immune signatures in immunotherapy-treated patients with advanced melanoma using a rank-based scoring approach

BACKGROUND

Gene expression profiling is increasingly being utilised as a diagnostic, prognostic and predictive tool for managing cancer patients. Single-sample scoring approach has been developed to alleviate instability of signature scores due to variations from sample composition. However, it is a challenge to achieve comparable signature scores across different expressional platforms.

METHODS

The pre-treatment biopsies from a total of 158 patients, who have received single-agent anti-PD-1 (n = 84) or anti-PD-1 + anti-CTLA-4 therapy (n = 74), were performed using NanoString PanCancer IO360 Panel. Multiple immune-related signature scores were measured from a single-sample rank-based scoring approach, singscore. We assessed the reproducibility and the performance in reporting immune profile of singscore based on NanoString assay in advance melanoma. To conduct cross-platform analyses, singscores between the immune profiles of NanoString assay and the previous orthogonal whole transcriptome sequencing (WTS) data were compared through linear regression and cross-platform prediction.

RESULTS

singscore-derived signature scores reported significantly high scores in responders in multiple PD-1, MHC-1-, CD8 T-cell-, antigen presentation-, cytokine- and chemokine-related signatures. We found that singscore provided stable and reproducible signature scores among the repeats in different batches and cross-sample normalisations. The cross-platform comparisons confirmed that singscores derived via NanoString and WTS were comparable. When singscore of WTS generated by the overlapping genes to the NanoString gene set, the signatures generated highly correlated cross-platform scores (Spearman correlation interquartile range (IQR) [0.88, 0.92] and r² IQR [0.77, 0.81]) and better prediction on cross-platform response (AUC = 86.3%). The model suggested that Tumour Inflammation Signature (TIS) and Personalised Immunotherapy Platform (PIP) PD-1 are informative signatures for predicting immunotherapy-response outcomes in advanced melanoma patients treated with anti-PD-1-based therapies.

CONCLUSIONS

Overall, the outcome of this study confirms that singscore based on NanoString data is a feasible approach to produce reliable signature scores for determining patients' immune profiles and the potential clinical utility in biomarker implementation, as well as to conduct cross-platform comparisons, such as WTS.

Treatment Challenges When Stopping Denosumab

Introduction Denosumab is commonly used to treat osteoporosis. However, discontinuation results in rebound bone loss and increased vertebral fracture risk. We report a clinical case series, illustrating the dilemma in deciding the best treatment should denosumab be stopped. Cases In eight patients aged 56-89 years, zolendronic acid after stopping denosumab resulted in BTM rises and BMD decline.  In a 68-year-old, two years of oral bisphosphonate after three years of denosumab resulted in elevated bone turnover markers (BTM) and decline in bone mineral density (BMD), necessitating a switch to zoledronic acid.  In a 79-year-old, two annual doses of zolendronic acid after three years of denosumab failed to suppress high BTM, with BMD dropping and denosumab being restarted.  In a 60-year-old, on stopping denosumab after 10 years of oral bisphosphonate, BMD remained stable despite no further therapy. Conclusion Drug holidays are not an option with denosumab, with a risk of bone loss even on transitioning to bisphosphonates. Risk is greater with longer duration of treatment6 and may be mitigated by prior bisphosphonate use. Standard dose zoledronic acid does not prevent bone loss in a significant proportion of patients. BTM may help in monitoring treatment and need for further bisphosphonates.

Acinic cell carcinoma of the salivary gland in the adult and paediatric population: a survival analysis

BACKGROUND

Acinic cell carcinoma (AcCC) is a rare malignant neoplasm of the salivary glands and generally considered to be a low-grade tumour. Surgical treatment is often curative, but a more aggressive high-grade variant has been associated with poorer survival and propensity for distant metastasis. No standard treatment guidelines exist and the approach to treatment is varied in the published series. The aim of this study is to present the experience of three major hospitals in Sydney, Australia, in treating AcCC of the salivary gland, with a focus on clinico-pathological features of disease and their associations with survival outcomes.

METHODS

Adult and paediatric cases of AcCC of the salivary gland during the time period 1979-2018 were retrospectively included. Demographic, clinico-pathological, treatment and survival outcome data were extracted. Survival analysis was undertaken to assess the effect of clinical and pathological variables on overall and disease-free survival.

RESULTS

Thirty-two cases were reviewed (29 adult and three paediatric). Thirty tumours (93.8%) were parotid gland primary tumours. Mean overall and disease-free survival was 17.0 ± 0.7 and 16.0 ± 0.9 years, respectively. Features associated with poorer survival were cT staging >1, presence of preoperative clinical facial nerve deficit and local recurrence. Positive margins were associated with recurrence.

CONCLUSION

These data suggest that disease-free and overall survival in AcCC of the salivary gland is excellent with surgery as the first-line treatment. Poor survival outcomes are uncommon and may be associated with locally advanced disease in the presence of other well-established high-risk features.

Are Tidal Salt Marshes Exposed to Nutrient Pollution more Vulnerable to Sea Level Rise?

Over the past four decades, Long Island, NY, USA, has lost coastal wetlands at a rate of 4% per decade due to submergence. In this study, we examined relationships between the rate of tidal salt marsh loss and environmental factors, including marsh elevation, tidal range, and wastewater exposure through analysis of stable isotope ratios of marsh soils and biota. Our goal was to identify factors that increase vulnerability of marshes to sea level rise, with a specific emphasis on the potential role of poor water quality in hastening marsh loss. Our results suggest that wastewater exposure may accelerate loss of intertidal marsh, but does not negatively impact high tidal marsh resilience to sea level rise. And while marsh elevation and tidal range were statistically significant predictors of marsh loss, they similarly displayed opposite relationships among marsh zones. This study suggests that different functional zones of coastal salt marshes may not respond similarly to global change factors, and that elevation may be an important factor mediating eutrophication effects to coastal salt marshes.

The use of the marine gastropod, Cellana tramoserica, as a biomonitor of metal contamination in near shore environments

The use of the marine gastropod, Cellana tramoserica, as a biomonitor of metal exposure was investigated. The factors influencing metal concentrations, such as mass, gender, substrate, shoreline position and temporal variation were examined. Tissue metal concentrations were mostly found to be independent of mass and gender. When metal concentrations were significantly correlated with mass, correlations were low and explained little variability. The underlying substrate and position in the littoral zone had only a small influence on metal concentrations. Variation between individuals, inherent variability due to genetic variability, was the most significant contribution to the overall variation in metal concentrations, resulting in positive skewing of population distributions. The mean metal concentrations varied temporally; metal masses were relatively constant with fluctuations in metal concentrations related to fluctuations in metal body burdens. The populations from a metal-contaminated site had significantly higher tissue Cu, Zn, As and Pb concentrations than the populations from relatively uncontaminated locations. C. tramoserica therefore can be considered to be a net accumulator of metals. A sample number of >10 is required to detect changes of 25 % from the mean concentrations at uncontaminated locations. This species meets the requirements of a suitable biomonitor for metal contaminants in the environment i.e. hardy, sessile, widespread, sufficient tissue mass and a metal accumulator. As the measurement of metal concentrations in C. tramesoria were influenced by substrate and shore position and, sometimes, mass, sites with similar substrates and organisms of similar mass and shoreline position should be chosen for comparison. When comparing metal concentrations in gastropods from different locations, they should be collected over the same period to minimise variability due to mass differences, spawning and other seasonal/temporal effects.

Evaluation of competition between a native and an invasive hornet species: do seasonal phenologies overlap?

One common dogma in ecology is based on the competitive exclusion principle. Hence, competition is often considered to be one of the primary determinants of the structure and functioning of ecosystems. In this paper, we investigate how the native Vespa crabro and the recently introduced Vespa velutina show some degree of niche differentiation that potentially minimizes their interspecific competition, the two dimensions investigated here being seasonal activity patterns and preferences for food. These two species share common characteristics: they are closely related, live in the same areas, belong to the same guild (predators), exploit the same kind of food sources, and exhibit a similar annual life cycle. Considering all these similarities, interspecific competition may occur if the two species exhibit identical seasonal phenologies. Our data show that their seasonal phenologies overlap to some extent probably due to biological constraints common to Vespinae. The shifts in time observed here allow the hornet species to not directly compete for food sources at the same time. It does not however exclude indirect competition, especially in a 'first-come, first-served' fashion.

Comparison of blood transfusion and surgical complications in peripartum hysterectomy when anticipated and unanticipated

The aim of the study was to determine the incidence and aetiology of peripartum hysterectomy (PH) for major obstetric haemorrhage (MOH) in our population and to compare estimated blood loss (EBL), blood transfusion, surgical complications and duration of hospital stay in PH that was anticipated and PH that was unanticipated. 26 cases of MOH requiring PH were identified from 50,548 women who delivered between 1 January 2006 and 31 December 2011 (0.5/1000). PH was anticipated in 17 and unanticipated in 9 cases. When compared, the anticipated group was more likely to have placenta accreta 15/17 (88%) vs 4/9 (44%): p = 0.03 and a gynaecological oncologist as the principal operator 15/17 (88%) vs 3/9 (33%): p = 0.007. The EBL 5.5 ± 3.7 SD vs 6.6 ± 3.9 SD l; p = 0.5, units of red cell concentrate or RCC transfused 7 ± 5 SD vs 9 ± 5 SD: p = 0.3, and mean operating time 134 ± 60 SD vs 190 ± 96 SD min: p = 0.07 were less in the anticipated than the unanticipated group, but not significantly so. The intraoperative complication rate 7/17 (41%) vs 3/9 (33%): p = 1.0 and the mean duration of hospital stay 7 ± 1 SD vs 8 ± 3 SD days: p = 0.27 were similar in both groups. PH is associated with a large volume of blood loss and significant surgical complications regardless of whether the procedure is anticipated or not.

[Hypoglycemic coma revealing a solitary fibrous tumor of the pleura]

INTRODUCTION

Solitary fibrous tumor of the pleura (TFSP) is rare. When associated with hypoglycemia it is commonly referred to as Doege-Potter syndrome.

CASE

A 51-year-old man was hospitalized for recurrent near-syncope associated with hypoglycemia. Clinical examination and then thoracic imaging clearly showed anomalies that corresponded to a mass occupying the entire left hemithorax. After resection, histological analysis diagnosed a fibrous tumor of the pleura.

DISCUSSION

Solitary fibrous tumors of the pleura are observed most often in patients aged 50 and 70 years. Hypoglycemia is rare, occurring in approximately 4% of cases. It is explained by the abnormal secretion of a type-II insulin-like growth factor. This tumor is treated by complete surgical excision.

Les tumeurs desmoïdes du creux sus-claviculaire (à propos de trois cas)

The authors report three cases of desmoid tumors of the shoulder-girdle. Through these observations and a review of the literature, they underline the specific characteristics of the desmoid tumors: the frequency and the seriousness of the localisations at the member roots and the great difficulties of the exeresis.

A bioassay to evaluate the activity of chemical stimuli from grape berries on the oviposition of Lobesia botrana (Lepidoptera: Tortricidae)

A two-choice bioassay was developed to evaluate the role of host-plant berry compounds on the oviposition site acceptance of the generalist moth Lobesia botrana (Denis & Shiffermüller). A key feature was the lining of the bioassay arena with felt which focused oviposition on the test substrates. Initial experiments comparing substrates with different physical features indicated that smooth textures and spherical shapes with interstices favour oviposition. Artificial oviposition substrates were thus constructed with glass spheres in order to test the behavioural activity of grapevine berry extracts. Only polar extracts obtained by soaking berries in methanol or water stimulated oviposition (more eggs were laid on the extract-treated substrate than on the control substrate), whereas more apolar ones obtained with chloroform or hexane had no significant effect. The prior removal of epicuticular waxes from grape berries before extraction did not enhance the stimulatory activity of the methanol extract. The oviposition response to this extract was dose-dependent. It is concluded that polar compounds present on grape berries act as oviposition stimulants for L. botrana.

Magnetic bead capture eliminates PCR inhibitors in samples collected from the airborne environment, permitting detection of Pneumocystis carinii DNA

PCR detection methods are useful in studies of organisms not amenable to culture. Inhibitors in environmental samples can interfere with such assays. We describe a magnetic bead DNA capture protocol that removes inhibitors from outdoor air samples, maintaining the sensitivity of a 16S Pneumocystis carinii mitochondrial rRNA gene-based PCR.

Development and evaluation of a molecular viability assay for Pneumocystis carinii

Despite recent declines in incidence, Pneumocystis carinii pneumonia (PCP) remains the most commonly occurring opportunistic illness among persons with AIDS in the United States. While P. carinii DNA has been detected in patient respiratory specimens and in air samples collected from various indoor environments housing PCP patients, the viability of these organisms is unknown. For this reason, we have developed and evaluated a molecular viability assay for P. carinii. This method is based upon the detection of P. carinii mRNA by a reverse transcription-PCR that employs specific primers from a member of the heat shock protein 70 family. Under optimal assay conditions, these primers were capable of detecting as few as 100 viable trophozoites as determined by ethidium bromide staining, while no signal was obtained from 10(6) trophozoites killed by heat, desiccation, or UV radiation. This assay was also capable of distinguishing P. carinii from other common fungi present in the air. Therefore, this molecular viability assay may be useful in conjunction with standard bioaerosol collection devices and procedures for the detection of viable P. carinii collected from various indoor environments. It may also be useful in confirming the presence of viable trophozoites in respiratory specimens collected by noninvasive techniques from putatively infected individuals.

[Quantification of relevant measurements of the petrous bone with computerized tomography before cochlear implant operation]

In this investigation the following anatomical measurements of the petrous bone preceding cochlear implant were evaluated using computed tomography (CT): the width of the basal coil of the cochlea, the thickness of the promontory, the distance between the sigmoid sinus and the posterior wall of the external auditory canal and the thickness of the squamous part of the temporal bone in the area of operation. Initially it was necessary to ascertain how accurately CT represents the anatomical structures of the petrous bone. The procedure of CT investigation in adult patients was simulated using the base of a skull. The CT plane in which the above mentioned measurements preceding cochlear implant can be made was represented and measurements were taken. Subsequently the same plane in CT was represented macroscopically with a specially developed method. The results show that anatomical structures measured in CT are magnified by 5% in contrast to the original. This magnification is presumably attributable to the computing of connective tissue which is adjacent to bone and the incapacity of CT to image structures of different density in the same voxel. In the second part of this investigation we evaluated 66 preoperative CT's of patients who were given a cochlear implant. The results must be adjusted by 5% to allow for this error in magnification. In conclusion a preoperative radiologic evaluation of the anatomical structures relevant to cochlear implant is without doubt tenable. Also the negligible difference between CT and the anatomical original requires no operative consequences. Because cochleostomy is carried out with a diamond burr of 1 mm diameter, a tenth of a millimeter is negligible according to our experience.