Efficacy of Preoperative Biopsy in Predicting the Newly Proposed Histologic Grade of Resected Lung Adenocarcinoma

A novel histologic grading system for invasive lung adenocarcinomas (LUAD) has been newly proposed and adopted by the World Health Organization (WHO) classification. We aimed to evaluate the concordance of newly established grades between preoperative biopsy and surgically resected LUAD samples. Additionally, factors affecting the concordance rate and its prognostic impact were also analyzed. In this study, surgically resected specimens of 222 patients with invasive LUAD and their preoperative biopsies collected between January 2013 and December 2020 were used. We determined the histologic subtypes of preoperative biopsy and surgically resected specimens and classified them separately according to the novel WHO grading system. The overall concordance rate of the novel WHO grades between preoperative biopsy and surgically resected samples was 81.5%, which was higher than that of the predominant subtype. When stratified by grades, the concordance rate of grades 1 (well-differentiated, 84.2%) and 3 (poorly differentiated, 89.1%) was found to be superior compared to grade 2 (moderately differentiated, 66.2%). Overall, the concordance rate was not significantly different from biopsy characteristics, including the number of biopsy samples, biopsy sample size, and tumor area size. On the other hand, the concordance rate of grades 1 and 2 was significantly higher in tumors with smaller invasive diameters, and that of grade 3 was significantly higher in tumors with larger invasive diameters. Preoperative biopsy specimens can predict the novel WHO grades, especially grades 1 and 3 of surgically resected specimens, more accurately than the former grading system, regardless of preoperative biopsy or clinicopathologic characteristics.

Deconvolution Tactics and Normalization in Renal Spatial Transcriptomics

The kidney is composed of heterogeneous groups of epithelial, endothelial, immune, and stromal cells, all in close anatomic proximity. Spatial transcriptomic technologies allow the interrogation of in situ expression signatures in health and disease, overlaid upon a histologic image. However, some spatial gene expression platforms have not yet reached single-cell resolution. As such, deconvolution of spatial transcriptomic spots is important to understand the proportion of cell signature arising from these varied cell types in each spot. This article reviews the various deconvolution strategies discussed in the 2021 Indiana O'Brien Center for Microscopy workshop. The unique features of Seurat transfer score methodology, SPOTlight, Robust Cell Type Decomposition, and BayesSpace are reviewed. The application of normalization and batch effect correction across spatial transcriptomic samples is also discussed.

Implementation of a Novel Web-Based Lesion Selection Tool to Improve Acquisition of Tumor Biopsy Specimens

Introduction

For maximum utility of molecular characterization by next-generation sequencing (NGS) and better understanding of tumor microenvironment with immune correlates analysis, biopsy specimens must yield adequate tumor tissue, and sequential biopsy specimens should sample a consistent site. We developed a web-based lesion selection tool (LST) that enables management and tracking of the biopsy specimen collections.

Methods

Of 145 patients, the LST was used for 88 patients; the other 57 served as controls. We evaluated consistency of the lesion biopsied in longitudinal collections, number of cores obtained, and cores with adequate tumor cellularity for NGS. The Fisher exact test and Wilcoxon rank sum test were used to identify differences between the groups.

Results

The analysis included 30 of 88 (34%) patients in the LST group and 52 of 57 (91%) in the control group. The LST workflow ensured 100% consistency in the lesions biopsied compared with 75% in the control group in longitudinal collections and increased the proportion of patients in whom at least five cores were collected per biopsy.

Conclusions

The novel LST platform facilitates coordination, performance, and management of longitudinal biopsy specimens. Use of the LST enables sampling of the designated lesion consistently, which is likely to accurately inform us the effect of the treatment on tumor microenvironment and evolution of resistant pathways. Such studies are important translational component of any clinical trials and research as they guide the development of next line of therapy, which has significant effect on clinical utility. However, validation of this approach in a larger study is warranted.

Intraepithelial CD163+ macrophages in tongue leukoplakia biopsy: A promising tool for cancer screening

OBJECTIVE

Oral leukoplakia has mixed and differing histopathological features, and it is thus difficult to reach an accurate histological diagnosis of oral leukoplakia based on a local biopsy alone. We recently demonstrated the significance of CD163⁺ macrophages in oral carcinogenesis. Herein we sought to determine whether CD163⁺ macrophages in biopsy specimens of oral leukoplakia help identify the overall histological nature of the lesion.

PATIENTS AND METHODS

Twenty-six patients with tongue leukoplakia who underwent a histological examination by both a preoperative local biopsy and consecutive total excision were enrolled. We evaluated clinicopathological factors and the expression of CD163⁺ macrophages based on a retrospective comparison of the histological diagnostic concordance between the biopsies and excisions.

RESULTS

Seventeen patients (diagnostic-agreement group) were diagnosed with squamous intraepithelial lesion based on both the biopsy and the excision. Nine patients (diagnostic-discrepancy group) were diagnosed with invasive cancer by excision, although invasive cancer was not observed in their biopsy specimens. Compared to the diagnostic-agreement group, the diagnostic-discrepancy group had more tongue leukoplakia with non-homogenous or high numbers of intraepithelial CD163⁺ macrophages.

CONCLUSION

The evaluation of intraepithelial CD163⁺ macrophages in local biopsy specimens from tongue leukoplakia patients is a promising tool for cancer screening.

[Application of tissue-marking dyes for pathologic examination of surgical and autopsy specimens]

OBJECTIVE

To assess the applicability of imported tissue-marking dyes and the samples of experimental dyes and decorative acrylic paints to mark the resection margins of a surgical specimen.

MATERIAL AND METHODS

Three sets of tissue-marking dyes: 2 imported sets and 1 experimental set, each containing red, orange, yellow, green, blue, purple, and black dyes, and a set of decorative acrylic paints containing black, blue, light blue, green, yellow, ocher, orange, magenta, and purple dyes. The experimental dyes and imported ones were used to mark tonsillar fragments obtained at tonsillectomy. The set of experimental dyes and that of decorative acrylic paints were used to stain the fragments of autopsy specimens (the skeletal muscles, pancreas, and large bowel). The tissues obtained at autopsy were marked before and after fixation in 40% formalin for 30 min and 24 hours. The specimens were subjected to standard tissue processing. Paraffin blocks were cut into 5-μm sections that were stained with hematoxylin and eosin. To estimate resection margin marking, each specimen was examined by 7 researchers who independently assessed the covering ability of a dye and its color in the paraffin block and microslides.

RESULTS

All researchers correctly identified purple, black, and green colors from the three sets of dyes in the surgical tonsillar specimen. When examining the autopsy specimens, all the experts correctly recognized magenta and green decorative acrylic paints and black and blue experimental dyes. The time of fixation and the type of tissue did not affect the color of a dye in the paraffin block and tissue specimen.

CONCLUSION

Some of experimental dyes and decorative acrylic paints are highly competitive with imported tissue-marking dyes in their characteristics, are correctly recognized in the block and tissue specimen under a microscope, and can be proposed to mark the resection margins of the examined tissues.

CT-guided aspiration lung biopsy for EGFR and ALK gene mutation analysis of lung cancer

The present study investigated the rates of detection and the positive rates of computed tomography (CT)-guided aspiration of lung biopsy for epidermal growth factor receptor (EGFR) gene and anaplastic lymphoma kinase (ALK) gene, and analyzed the relationship between gene mutation and clinical characteristics to improve the rate of related factors of gene detection. The clinical data and CT-guided aspiration biopsy specimen of 250 patients with lung cancer. Data showed that the rate of EGFR gene mutation was 41.2% (103/250) in biopsy specimens of non-small cell lung cancer patients. The rate of EGFR gene mutation of adenocarcinoma (56.6%, P<0.01) was higher than other types of lung cancer. ALK gene mutation of patients in phase IV was obviously higher than that of patients not in phase IV (18.5 and 1.8%, P<0.01). The rate of EGFR gene detection was 83.2% (208/250). The rate of detection of tumor cells >50 was higher. The rate of ALK protein immunohistochemical detection was 87.2%, and the rate of coarse needle biopsy detection was higher than that of the fine needle (91 and 72%, P<0.01), but the positive rate between coarse needle biopsy and fine needle biopsy had no difference (P>0.05). The rate of detection was associated with tumor cell number (P<0.05), and had no correlation with the proportion of tumor cells (P>0.05). The rate of detection of EGFR and ALK genes was associated with tumor cell number and had no correlation with the proportion of tumor cells. The rate of detection is higher when the number of tumor cells is more than 50.

Increased metallothionein expression reflects steroid resistance in renal allograft recipients

Steroid-refractory acute rejection is a risk factor for inferior renal allograft outcome. We aimed to gain insight into the mechanisms underlying steroid resistance by identifying novel molecular markers of steroid-refractory acute rejection. Eighty-three kidney transplant recipients (1995-2005), who were treated with methylprednisolone during a first acute rejection episode, were included in this study. Gene expression patterns were investigated in a discovery cohort of 36 acute rejection biopsies, and verified in a validation cohort of 47 acute rejection biopsies. In the discovery set, expression of metallothioneins (MT) was significantly (p < 0.000001) associated with decreased response to steroid treatment. Multivariate analysis resulted in a predictive model containing MT-1 as an independent covariate (AUC = 0.88, p < 0.0000001). In the validation set, MT-1 expression was also significantly associated with steroid resistance (p = 0.029). Metallothionein expression was detected in macrophages and tubular epithelial cells. Parallel to the findings in patients, in vitro experiments of peripheral blood mononuclear cells from 11 donors showed that nonresponse to methylprednisolone treatment is related to highly elevated MT levels. High expression of metallothioneins in renal allografts is associated with resistance to steroid treatment. Metallothioneins regulate intracellular concentrations of zinc, through which they may diminish the zinc-requiring anti-inflammatory effect of the glucocorticoid receptor.

Multiparametric in situ mRNA hybridization analysis of gastric biopsies predicts lymph node metastasis in patients with gastric carcinoma

We examined the expression level of several genes that regulate different steps in metastasis formation in formalin-fixed, paraffin-embedded biopsies of 189 primary human gastric carcinomas prior to surgical resection in patients in whom lymph node metastasis was not evident by endoscopic ultrasound or computed tomography (CT) scan. The expressions of epidermal growth factor receptor (EGF-R), vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-2 and E-cadherin were examined by a colorimetric in situ mRNA hybridization technique. The integrity of the mRNAs was verified, leaving 161 (85.2%) patients for study. After gastrectomy, 82 patients had positive lymph nodes and 79 patients had negative lymph nodes. The concurrent expression levels of MMP-2 and E-cadherin mRNAs were significantly higher and lower, respectively, in the metastatic tumors than the non-metastatic tumors. Expression of EGF-R and VEGF was not different between the metastatic and non-metastatic tumors. However, when only the intestinal-type of gastric cancer was evaluated, the level of VEGF mRNA was significantly higher in tumors associated with lymph node metastasis than in those without metastasis. However, a high MMP-2:E-cadherin ratio significantly correlated with lymph node metastasis in both types of gastric cancer. These results suggest that multiparametric in situ hybridization analysis for several metastasis-related genes may allow the preoperative prediction of lymph node metastasis from gastric cancer.