Autoimmunity in thymic epithelial tumors: a not yet clarified pathologic paradigm associated with several unmet clinical needs

Thymic epithelial tumors (TETs) are rare mediastinal cancers originating from the thymus, classified in two main histotypes: thymoma and thymic carcinoma (TC). TETs affect a primary lymphoid organ playing a critical role in keeping T-cell homeostasis and ensuring an adequate immunological tolerance against "self". In particular, thymomas and not TC are frequently associated with autoimmune diseases (ADs), with Myasthenia Gravis being the most common AD present in 30% of patients with thymoma. This comorbidity, in addition to negatively affecting the quality and duration of patients' life, reduces the spectrum of the available therapeutic options. Indeed, the presence of autoimmunity represents an exclusion criteria for the administration of the newest immunotherapeutic treatments with checkpoint inhibitors. The pathophysiological correlation between TETs and autoimmunity remains a mystery. Several studies have demonstrated the presence of a residual and active thymopoiesis in adult patients affected by thymomas, especially in mixed and lymphocytic-rich thymomas, currently known as type AB and B thymomas. The aim of this review is to provide the state of art in regard to the histological features of the different TET histotype, to the role of the different immune cells infiltrating tumor microenvironments and their impact in the break of central immunologic thymic tolerance in thymomas. We discuss here both cellular and molecular immunologic mechanisms inducing the onset of autoimmunity in TETs, limiting the portfolio of therapeutic strategies against TETs and greatly impacting the prognosis of associated autoimmune diseases.

Filamin A is involved in human intrahepatic cholangiocarcinoma aggressiveness and progression

BACKGROUND & AIMS

Intrahepatic cholangiocarcinoma (iCCA) is a primary liver tumour, characterized by poor prognosis and lack of effective therapy. The cytoskeleton protein Filamin A (FLNA) is involved in cancer progression and metastasis, including primary liver cancer. FLNA is cleaved by calpain, producing a 90 kDa fragment (FLNACT ) that can translocate to the nucleus and inhibit gene transcription. We herein aim to define the role of FLNA and its cleavage in iCCA carcinogenesis.

METHODS & RESULTS

We evaluated the expression and localization of FLNA and FLNACT in liver samples from iCCA patients (n = 82) revealing that FLNA expression was independently correlated with disease-free survival. Primary tumour cells isolated from resected iCCA patients expressed both FLNA and FLNACT , and bulk RNA sequencing revealed a significant enrichment of cell proliferation and cell motility pathways in iCCAs with high FLNA expression. Further, we defined the impact of FLNA and FLNACT on the proliferation and migration of primary iCCA cells (n = 3) and HuCCT1 cell line using silencing and Calpeptin, a calpain inhibitor. We observed that FLNA silencing decreased cell proliferation and migration and Calpeptin was able to reduce FLNACT expression in both the HuCCT1 and iCCA cells (p < .05 vs. control). Moreover, Calpeptin 100 μM decreased HuCCT1 and primary iCCA cell proliferation (p <.00001 vs. control) and migration (p < .05 vs. control).

CONCLUSIONS

These findings demonstrate that FLNA is involved in human iCCA progression and calpeptin strongly decreased FLNACT expression, reducing cell proliferation and migration.

Deep learning-based phenotyping reclassifies combined hepatocellular-cholangiocarcinoma

Primary liver cancer arises either from hepatocytic or biliary lineage cells, giving rise to hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICCA). Combined hepatocellular- cholangiocarcinomas (cHCC-CCA) exhibit equivocal or mixed features of both, causing diagnostic uncertainty and difficulty in determining proper management. Here, we perform a comprehensive deep learning-based phenotyping of multiple cohorts of patients. We show that deep learning can reproduce the diagnosis of HCC vs. CCA with a high performance. We analyze a series of 405 cHCC-CCA patients and demonstrate that the model can reclassify the tumors as HCC or ICCA, and that the predictions are consistent with clinical outcomes, genetic alterations and in situ spatial gene expression profiling. This type of approach could improve treatment decisions and ultimately clinical outcome for patients with rare and biphenotypic cancers such as cHCC-CCA.

Artificial intelligence-based pathology as a biomarker of sensitivity to atezolizumab-bevacizumab in patients with hepatocellular carcinoma: a multicentre retrospective study

BACKGROUND

Clinical benefits of atezolizumab plus bevacizumab (atezolizumab-bevacizumab) are observed only in a subset of patients with hepatocellular carcinoma and the development of biomarkers is needed to improve therapeutic strategies. The atezolizumab-bevacizumab response signature (ABRS), assessed by molecular biology profiling techniques, has been shown to be associated with progression-free survival after treatment initiation. The primary objective of our study was to develop an artificial intelligence (AI) model able to estimate ABRS expression directly from histological slides, and to evaluate if model predictions were associated with progression-free survival.

METHODS

In this multicentre retrospective study, we developed a model (ABRS-prediction; ABRS-P), which was derived from the previously published clustering-constrained attention multiple instance learning (or CLAM) pipeline. We trained the model fit for regression analysis using a multicentre dataset from The Cancer Genome Atlas (patients treated by surgical resection, n=336). The ABRS-P model was externally validated on two independent series of samples from patients with hepatocellular carcinoma (a surgical resection series, n=225; and a biopsy series, n=157). The predictive value of the model was further tested in a series of biopsy samples from a multicentre cohort of patients with hepatocellular carcinoma treated with atezolizumab-bevacizumab (n=122). All samples in the study were from adults (aged ≥18 years). The validation sets were sampled between Jan 1, 2008, to Jan 1, 2023. For the multicentre validation set, the primary objective was to assess the association of high versus low ABRS-P values, defined relative to cross-validation median split thresholds in the first biopsy series, with progression-free survival after treatment initiation. Finally, we performed spatial transcriptomics and matched prediction heatmaps with in situ expression profiles.

FINDINGS

Of the 840 patients sampled, 641 (76%) were male and 199 (24%) were female. Across the development and validation datasets, hepatocellular carcinoma risk factors included alcohol intake, hepatitis B and C virus infections, and non-alcoholic steatohepatitis. Using cross-validation in the development series, the mean Pearson's correlation between ABRS-P values and ABRS score (mean expression of ABRS genes) was r=0·62 (SD 0·09; mean p<0·0001, SD<0·0001). The ABRS-P generalised well on the external validation series (surgical resection series, r=0·60 [95% CI 0·51-0·68], p<0·0001; biopsy series, r=0·53 [0·40-0·63], p<0·0001). In the 122 patients treated with atezolizumab-bevacizumab, those with ABRS-P-high tumours (n=74) showed significantly longer median progression-free survival than those with ABRS-P-low tumours (n=48) after treatment initiation (12 months [95% CI 7-not reached] vs 7 months [4-9]; p=0·014). Spatial transcriptomics showed significantly higher ABRS score, along with upregulation of various other immune effectors, in tumour areas with high ABRS-P values versus areas with low ABRS-P values.

INTERPRETATION

Our study indicates that AI applied on hepatocellular carcinoma digital slides is able to serve as a biomarker for progression-free survival in patients treated with atezolizumab-bevacizumab. This approach could be used in the development of inexpensive and fast biomarkers for targeted therapies. The combination of AI heatmaps with spatial transcriptomics provides insight on the molecular features associated with predictions. This methodology could be applied to other cancers or diseases and improve understanding of the biological mechanisms that drive responses to treatments.

FUNDING

Institut National du Cancer, Fondation ARC, China Scholarship Council, Ligue Contre le Cancer du Val de Marne, Fondation de l'Avenir, Ipsen, and Fondation Bristol Myers Squibb Pour la Recherche en Immuno-Oncologie.

Preoperative systemic inflammatory markers as prognostic factors in differentiated thyroid cancer: a systematic review and meta-analysis

BACKGROUND

Inflammation has been associated with tumor development and circulating inflammatory biomarkers have been proposed as possible predictors of recurrence of several solid tumors. However, the role of inflammation markers in differentiated thyroid carcinoma (DTC) is still uncertain.

OBJECTIVE

This meta-analysis aimed to assess the prognostic value of neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) in patients with DTC.

METHODS

Studies investigating the association between survival and preoperative circulating inflammatory markers in DTC patients were included. The primary outcome was disease-free survival (DFS). Cumulative logarithms of the hazard ratio (log-HRs) with 95% CI were calculated through the inverse variance method using a random-effects model.

RESULTS

A total of 7599 patients with a mean age of 48.89 (95% CI 44.16-53.63) were included. The estimated pooled log-HRs for DFS were 0.07 for NLR (95% CI -0.12-0.26; p = 0.43), -0.58 for LMR (95% CI -1.21-0.05; p = 0.06), and 0.01 (95% CI 0-0.01; p = 0.21) for PLR.

CONCLUSIONS

Our meta-analysis showed no association between NLR, PLR, LMR and DFS in DTC; however, more prospective data are needed to better define the association between inflammatory status and prognosis of DTC.

Exploring a novel composite method using non-contrast EUS enhanced microvascular imaging and cyst fluid analysis to differentiate pancreatic cystic lesions

BACKGROUND AND AIMS

Differentiating pancreatic cystic lesions (PCLs) remains a diagnostic challenge. The use of high-definition imaging modalities which detect tumor microvasculature have been described in solid lesions. We aim to evaluate the usefulness of cystic microvasculature when used in combination with cyst fluid biochemistry to differentiate PCLs.

METHODS

We retrospectively analyzed 110 consecutive patients with PCLs from 2 Italian Hospitals who underwent EUS with H-Flow and EUS fine needle aspiration to obtain cystic fluid. The accuracy of fluid biomarkers was evaluated against morphological features on radiology and EUS. Gold standard for diagnosis was surgical resection. A clinical and radiological follow up was applied in those patients who were not resected because not surgical indication and no signs of malignancy were shown.

RESULTS

Of 110 patients, 65 were diagnosed with a mucinous cyst, 41 with a non-mucinous cyst, and 4 with an undetermined cyst. Fluid analysis alone yielded 76.7% sensitivity, 56.7% specificity, 77.8 positive predictive value (PPV), 55.3 negative predictive value (NPV) and 56% accuracy in diagnosing pancreatic cysts alone. Our composite method yielded 97.3% sensitivity, 77.1% specificity, 90.1% PPV, 93.1% NPV, 73.2% accuracy.

CONCLUSIONS

This new composite could be applied to the holistic approach of combining cyst morphology, vascularity, and fluid analysis alongside endoscopist expertise.

Tumor-infiltrating lymphocytes and tumor-associated macrophages as potential predictors of lymph node metastases in major salivary gland cancers

Purpose

The purpose of this study is to define if tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) could represent potential predictors of lymph node metastases (LNM) in salivary gland cancers (SGC).

Methods

A selected number of immunohistochemical markers related to TILs (CD3, CD4, CD68, and FOXP3) and TAMs (CD68 and CD163) were investigated on major salivary gland cancers. TIL and TAM densities were measured on digital images using the open-source QuPath both in the tumor interior (TI) and invasive margin (IM). Correlation with pathologic N classification and follow-up clinical data was investigated.

Results

A total of 25 consecutive patients (men: 11; median age: 62.0) were included. Densities of CD3+ IM (OR = 7.7, 95% CI 1.2-51.2), CD8+ TI (OR = 7.7, 95% CI 1.2-51.2), CD8+ IM (OR = 7.7, 95% CI 1.2-51.2), FOXP3+ TI (OR = 24.0, 95% CI 2.2-255.9), CD68+ TI (OR = 7.7, 95% CI 1.2-51.2), and CD163+ IM (OR = 7.7, 95% CI 1.2 - 51.2), and the Immunoscore CD8/CD3 (OR = 1.9, 95% CI 1.1-3.4) were significantly associated with LNM (p < 0.05). CD3+ TI density was significantly associated with tumor recurrence and death (HR = 5.8, 95% CI 1.5-22.6; p < 0.05).

Conclusion

A high density of specific TIL and TAM subpopulations might be correlated with a higher probability of LNM in SGC.

Prognostic Impact of Tumor Immune Microenvironment and Its Predictive Role in Salivary Gland Cancer

BACKGROUND

Recently, many studies have investigated the role of tumor immune microenvironment (TIME) in carcinogenesis, highlighting its relation to both tumor regression and progression. In particular, the "inflammatory system", made of innate and adaptive immune cells, interacts with cancer cells and their surrounding stroma. In this setting, the aim of this review is to summarize the current literature regarding the TIME of major salivary gland carcinomas (MSGCs), with particular attention on the characteristics and prognostic role of tumor infiltrating lymphocytes (TILs), the mechanisms that lead to TILs exhaustion and the important additional immune infiltrating factors that help SGC progression or remission.

METHODS

A comprehensive literature search was performed concerning published articles on the role of TIME in MSGCs.

RESULTS

In this work we summarize the advancing knowledge on TIME in SGCs by demonstrating the key prognostic and/or predictive value of specific immune features.

CONCLUSION

From the analysis of the current 'status of the art' it clearly emerges a need for precise, unambiguous phenotyping of immune cell populations, as well as a more thorough understanding of the frequencies and interactions of multiple immune cell types inside the TIME and their spatial localization (intratumoral vs. stromal).

Macrophage morphology and distribution are strong predictors of prognosis in resected colorectal liver metastases: results from an external retrospective observational study

INTRODUCTION

Tumor-associated macrophages (TAMs) are key components of a tumoral microenvironment and have been shown to impact prognosis in different cancers. Previously reported data showed that TAM morphology correlates with prognosis in colorectal liver metastases (CLMs) after hepatectomy, with smaller TAMs (S-TAMs) conferring a more favorable prognosis than larger ones (L-TAMs). This study aims to externally validate this finding.

MATERIAL AND METHODS

The external cohort consisted of 84 formalin-fixed and paraffin-embedded surgical samples of CLMs and peritumoral tissue. Two-micrometer-section slides were obtained; the area and perimeter of 21 macrophages in each slide were recorded. The endpoints were TAMs morphometrics and their prognostic significance in relation to disease-free survival (DFS).

RESULTS

The average macrophage perimeter was 71.5±14.1 μm whilst the average area was 217.7±67.8 μm 2 . At univariate analysis, the TAM area demonstrated a statistically significant association with DFS ( P =0.0006). Optimal area cutoff value was obtained, showing a sensitivity and specificity of 92 and 56%, respectively. S-TAMs and L-TAMs were associated with 3-year DFS rates of 60 and 8.5%, respectively ( P <0.001). Multivariate analysis confirmed the predictive role of TAM area for DFS [hazard ratio (HR)=5.03; 95% CI=1.70-14.94; P =0.003]. Moreover, in a subset of patients ( n =12) characterized by unfavorable ( n =6, recurrence within 3 months) or favorable ( n =6, no recurrence after 48 months) prognosis, TAMs showed a different distribution: L-TAMs were more abundant and closer to the tumor invasive margin in patients that encountered early recurrence and tended to cluster in foci significantly larger ( P =0.02).

CONCLUSIONS

This external validation confirms that morphometric characterization of TAMs can serve as a simple readout of their diversity and allows to reliably stratify patient outcomes and predict disease recurrence after hepatectomy for CLMs.

Quantitative Analysis of the Histological Features of Tuberous Breast

INTRODUCTION

Tuberous breast deformity (TB) is a condition mostly characterized by breast stenosis, areolar widening and glandular asymmetry. The most accredited hypothesis describes an abnormal thickening of the fascia corporis that might influence an alteration in the glandular development, limiting the horizontal growth of breast parenchyma. Alterations in the extracellular matrix components (ECM) might be involved in the abnormal breast development.

PATIENTS

The aim of our case control study is to use histological specimens to analyze qualitative and quantitative differences in collagen fibers, elastic fibers and vessel densities in TB and normal breasts of 20 patients using a software for digital pathology.

RESULTS

The quantitative findings showed increasing concentrations of collagen fibers and decreasing elastic fibers in TB, compared to normal breasts. No difference was seen in vessel density among the two groups. The qualitative findings highlighted differences in the distribution of the ECM among the TB specimens. Collagen fibers showed a packed appearance rather a scattered distribution, while elastic fibers visibly presented a reduction and a focal distribution of their concentration.

CONCLUSIONS

The study proposes a correlation between abnormalities in ECM concentrations and TB, resulting in a higher degree of fibrosis and in the characteristic stenotic and less elastic morphology of the deformity.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Combined Inhibition of Smoothened and the DNA Damage Checkpoint WEE1 Exerts Antitumor Activity in Cholangiocarcinoma

Cholangiocarcinoma (CCA) is characterized by resistance to chemotherapy and a poor prognosis. Therefore, treatments that can effectively suppress tumor growth are urgently needed. Aberrant activation of hedgehog (HH) signaling has been implicated in several cancers, including those of the hepatobiliary tract. However, the role of HH signaling in intrahepatic CCA (iCCA) has not been completely elucidated. In this study, we addressed the function of the main transducer Smoothened (SMO) and the transcription factors (TFs) GLI1 and GLI2 in iCCA. In addition, we evaluated the potential benefits of the combined inhibition of SMO and the DNA damage kinase WEE1. Transcriptomic analysis of 152 human iCCA samples showed increased expression of GLI1, GLI2, and Patched 1 (PTCH1) in tumor tissues compared with nontumor tissues. Genetic silencing of SMO, GLI1, and GLI2 inhibited the growth, survival, invasiveness, and self-renewal of iCCA cells. Pharmacologic inhibition of SMO reduced iCCA growth and viability in vitro, by inducing double-strand break DNA damage, leading to mitotic arrest and apoptotic cell death. Importantly, SMO inhibition resulted in the activation of the G2-M checkpoint and DNA damage kinase WEE1, increasing the vulnerability to WEE1 inhibition. Hence, the combination of MRT-92 with the WEE1 inhibitor AZD-1775 showed increased antitumor activity in vitro and in iCCA xenografts compared with single treatments. These data indicate that combined inhibition of SMO and WEE1 reduces tumor burden and may represent a strategy for the clinical development of novel therapeutic approaches in iCCA.

High-resolution analysis of mononuclear phagocytes reveals GPNMB as a prognostic marker in human colorectal liver metastasis

Patients with colorectal liver metastasis (CLM) present with heterogenous clinical outcomes and improved classification is needed to ameliorate the therapeutic output. Macrophages (MΦ) hold promise as prognostic classifiers and therapeutic targets. Here, stemming from a single-cell analysis of mononuclear phagocytes infiltrating human CLM, we identified two M markers associated with distinct populations with opposite clinical relevance. The invasive margin of CLM was enriched in pro-inflammatory monocyte-derived MΦ (MoMΦ) expressing the monocytic marker SERPINB2, and a more differentiated population, TAMs, expressing GPNMB. SERPINB2+ MoMΦ had an early inflammatory profile, whereas GPNMB+ TAMs were enriched in pathways of matrix degradation, angiogenesis and lipid metabolism and were found closer to the tumor margin, as confirmed by spatial transcriptomics on CLM specimens. In a cohort of patients, a high infiltration of SERPINB2+ cells independently associated with longer disease-free survival (DFS) (P=0.033), whereas a high density of GPNMB+ cells correlated with shorter DFS (P=0.012) and overall survival (OS) (P=0.002). Cell-cell interaction analysis defined opposing roles for MoMΦ and TAMs, suggesting that SERPINB2+ and GPNMB+ cells are discrete populations of MΦ and may be exploited for further translation to an immune-based stratification tool. This study provides evidence of how multi-omics approaches can identify non-redundant, clinically relevant markers for further translation to immune-based patient stratification tools and therapeutic targets. GPNMB has been shown to set macrophages in an immunosuppressive mode. Our high dimensional analyses provide further evidence that GPNMB is a negative prognostic indicator and a potential player in the pro-tumor function of macrophage populations.

Multimodal single-cell profiling of intrahepatic cholangiocarcinoma defines hyperactivated Tregs as a potential therapeutic target

BACKGROUND & AIMS

The landscape and function of the immune infiltrate of intrahepatic cholangiocarcinoma (iCCA), a rare, yet aggressive tumor of the biliary tract, remains poorly characterized, limiting development of successful immunotherapies. Herein, we aimed to define the molecular characteristics of tumor-infiltrating leukocytes with a special focus on CD4+ regulatory T cells (Tregs).

METHODS

We used high-dimensional single-cell technologies to characterize the T-cell and myeloid compartments of iCCA tissues, comparing these with their tumor-free peritumoral and circulating counterparts. We further used genomics and cellular assays to define the iCCA-specific role of a novel transcription factor, mesenchyme homeobox 1 (MEOX1), in Treg biology.

RESULTS

We found poor infiltration of putative tumor-specific CD39+ CD8+ T cells accompanied by abundant infiltration of hyperactivated CD4+ Tregs. Single-cell RNA-sequencing identified an altered network of transcription factors in iCCA-infiltrating compared to peritumoral T cells, suggesting reduced effector functions by tumor-infiltrating CD8+ T cells and enhanced immunosuppression by CD4+ Tregs. Specifically, we found that expression of MEOX1 was highly enriched in tumor-infiltrating Tregs, and demonstrated that MEOX1 overexpression is sufficient to reprogram circulating Tregs to acquire the transcriptional and epigenetic landscape of tumor-infiltrating Tregs. Accordingly, enrichment of the MEOX1-dependent gene program in Tregs was strongly associated with poor prognosis in a large cohort of patients with iCCA.

CONCLUSIONS

We observed abundant infiltration of hyperactivated CD4+ Tregs in iCCA tumors along with reduced CD8+ T-cell effector functions. Interfering with hyperactivated Tregs should be explored as an approach to enhance antitumor immunity in iCCA.

LAY SUMMARY

Immune cells have the potential to slow or halt the progression of tumors. However, some tumors, such as intrahepatic cholangiocarcinoma, are associated with very limited immune responses (and infiltration of cancer-targeting immune cells). Herein, we show that a specific population of regulatory T cells (a type of immune cell that actually suppresses the immune response) are hyperactivated in intrahepatic cholangiocarcinoma. Targeting these cells could enable cancer-targeting immune cells to act more effectively and should be looked at as a potential therapeutic approach to this aggressive cancer type.

Multidisciplinary Tumor Board in the Management of Patients with Colorectal Liver Metastases: A Single-Center Review of 847 Patients

There is still debate over how reviewing oncological histories and addressing appropriate therapies in multidisciplinary team (MDT) discussions may affect patients’ overall survival (OS). The aim of this study was to describe MDT outcomes for a single cancer center’s patients affected by colorectal liver metastases (CRLMs). From 2010 to 2020, a total of 847 patients with CRLMs were discussed at our weekly MDT meeting. Patients’ characteristics and MDT decisions were analyzed in two groups: patients receiving systemic therapy (ST) versus patients receiving locoregional treatment (LRT). Propensity-score matching (PSM) was run to reduce the risk of selection bias. The median time from MDT indication to treatment was 27 (IQR 13−51) days. The median OS was 30 (95%CI = 27−34) months. After PSM, OS for patients undergoing LRT was 51 (95%CI = 36−64) months compared with 15 (95%CI = 13−20) months for ST patients (p < 0.0001). In this large retrospective study, the MDT discussions were useful in providing the patients with all available locoregional options.

T-cell exhaustion and residency dynamics inform clinical outcomes in hepatocellular carcinoma

BACKGROUND & AIMS

Despite recent translation of immunotherapies into clinical practice, the immunobiology of hepatocellular carcinoma (HCC), in particular the role and clinical relevance of exhausted and liver-resident T cells remain unclear. We therefore dissected the landscape of exhausted and resident T cell responses in the peripheral blood and tumor microenvironment of patients with HCC.

METHODS

Lymphocytes were isolated from the blood, tumor and tumor-surrounding liver tissue of patients with HCC (n = 40, n = 10 treated with anti-PD-1 therapy). Phenotype, function and response to anti-PD-1 were analyzed by mass and flow cytometry ex vivo and in vitro, tissue residence was further assessed by immunohistochemistry and imaging mass cytometry. Gene signatures were analyzed in silico.

RESULTS

We identified significant enrichment of heterogeneous populations of exhausted CD8+ T cells (TEX) in the tumor microenvironment. Strong enrichment of severely exhausted CD8 T cells expressing multiple immune checkpoints in addition to PD-1 was linked to poor progression-free and overall survival. In contrast, PD-1 was also expressed on a subset of more functional and metabolically active CD103+ tissue-resident memory T cells (TRM) that expressed few additional immune checkpoints and were associated with better survival. TEX enrichment was independent of BCLC stage, alpha-fetoprotein levels or age as a variable for progression-free survival in our cohort. These findings were in line with in silico gene signature analysis of HCC tumor transcriptomes from The Cancer Genome Atlas. A higher baseline TRM/TEX ratio was associated with disease control in anti-PD-1-treated patients.

CONCLUSION

Our data provide information on the role of peripheral and intratumoral TEX-TRM dynamics in determining outcomes in patients with HCC. The dynamics between exhausted and liver-resident T cells have implications for immune-based diagnostics, rational patient selection and monitoring during HCC immunotherapies.

LAY SUMMARY

The role of the immune response in hepatocellular carcinoma (HCC) remains unclear. T cells can mediate protection against tumor cells but are frequently dysfunctional and exhausted in cancer. We found that patients with a predominance of exhausted CD8+ T cells (TEX) had poor survival compared to patients with a predominance of tissue-resident memory T cells (TRM). This correlated with the molecular profile, metabolic and functional status of these cell populations. The enrichment of TEX was independently associated with prognosis in addition to disease stage, age and tumor markers. A high TRM proportion was also associated with better outcomes following checkpoint therapy. Thus, these T-cell populations are novel biomarkers with relevance in HCC.

Prognostic value of vessels encapsulating tumor clusters (VETC) in sarcoma

e23523

Background: How sarcoma metastasize is unknown. VETC has been described as an epithelial-to-mesenchymal-transition independent process of metastasis: endothelium covers neoplastic clusters allowing tumor dissemination. It has also been shown to be a predictive of tyrosine kinase inhibitors (TKI) response. The objectives of the present study are: 1) to assess the presence of VETC in sarcoma; 2) to model its prognostic role. Methods: The study was retrospective. We selected 54 cases of sarcomas (6 DDLPS, 10 GIST, 6 retroperitoneal LMS, 9 MLPS, 8 MPNST, 10 SFT, 5 UPS); of them 31 were metastatic (M1 group), 23 were not (M0 group, defined as least 5 years of negative follow-up). High risk GIST and SFT, and grade 3 FNCLCC were considered high grade. VETC was assessed with CD31 immunohistochemistry and defined as a continuous endothelial lining around tumor clusters. We used Bayesian probabilistic modeling to detect small effects and multilevel hierarchical modeling to reduce overfitting. Models were fit using Stan and R. CI were computed with the HPDI method for 89%. The whole posterior probability (PP) was used for calculations. Results: The two groups (M0 & M1) were substantially homogeneous: the CI of the contrast PP (CPP) included 0 in each histology for sex, age, size, and grade; VETC was more expressed in M1 SFT cases with almost all the CPP mass above the 0. Also, UPS and GIST showed VETC to be more present in metastatic diseases with 79% and 78% respectively of the CPP mass above 0 (see table). Metastasis free survival (MFS) analysis showed that VETC in SFT and UPS with a coefficient of 2.42 (CI 0.73 – 4.65) and 1.94 (CI 0.16 – 3.67); for the latter the median was reached with a PP density of median MFS of 65 months (mo) (standard deviation, SD: 74 mo) for VETC- Vs 11 mo (SD: 14 mo) for VETC+. Similarly, disease specific survival analysis showed – in SFT and UPS – that VETC was negatively associated with prognosis with coefficients of 1.24 and 2.34; however the CI covered slightly the 0 (-0.54 – 3.96 and -0.09 – 5.73, respectively). Conclusions: We found VETC in sarcoma and highlighted its prognostic role in SFT and UPS. [Table: see text]

Review of Tuberous Breast Deformity: Developments over the Last 20 Years

Tuberous breast (TB) deformity is a condition characterized by alterations in breast morphology and tissue structure with high prevalence in the general population. The literature provides sparse descriptions of TB, as not many investigations on the condition have been conducted. The aim of this review was to analyze and provide a holistic overview on the morphological characteristics of the TB.

Methods

A review of current literature was performed using the PubMed database from 2001 to 2021. The key words used for the review included "tuberous breast," "constricted breast," and "stenotic breast." We included articles that analyzed the anatomic and histologic characteristics of TB.

Results

From 213 articles, only 42 met the inclusion criteria. A total of 171 articles were excluded, as they were letters, not related to the condition, or were written in a foreign language. The studies in this review drew on hypothesis on the embryological origin of TB and analyzed the composition of TB tissues, consisting in a constricting fibrous ring, made of longitudinally arranged collagen and elastic fibers. Furthermore, the review reports the different anatomical and surgical classifications, as well as the various surgical corrective procedures developed throughout history up to 2021.

Conclusion

The review describes all etiological, epidemiologic, anatomical, histological, and surgical characteristics of tuberous breast.

A clinical and pathological update on hepatocellular carcinoma

It is estimated that more than 1 million individuals will be affected annually by hepatocellular carcinoma (HCC) by 2025. HCC can be broadly grouped into two major molecular subgroups, each of which is characterized by specific morphological and phenotypic features that mirror the genetic background. The use of these tissue biomarkers in the daily practice of pathologists promises to better allocate patients with HCC with adequate treatments. In turn, this will likely boost the attitude of clinicians toward obtaining a pre-treatment biopsy.

Genomic analysis of focal nodular hyperplasia with associated hepatocellular carcinoma unveils its malignant potential: a case report

Background

Focal nodular hyperplasia (FNH) is typically considered a benign tumor of the liver without malignant potential. The co-occurrence of FNH and hepatocellular carcinoma (HCC) has been reported in rare cases. In this study we sought to investigate the clonal relationship between these lesions in a patient with FNH-HCC co-occurrence.

Methods

A 74-year-old female patient underwent liver tumor resection. The resected nodule was subjected to histologic analyses using hematoxylin and eosin stain and immunohistochemistry. DNA extracted from microdissected FNH and HCC regions was subjected to whole exome sequencing. Clonality analysis were performed using PyClone.

Results

Histologic analysis reveals that the nodule consists of an FNH and two adjoining HCC components with distinct histopathological features. Immunophenotypic characterization and genomic analyses suggest that the FNH is clonally related to the HCC components, and is composed of multiple clones at diagnosis, that are likely to have progressed to HCC through clonal selection and/or the acquisition of additional genetic events.

Conclusion

To the best of our knowledge, our work is the first study showing a clonal relationship between FNH and HCC. We show that FNH may possess the capability to undergo malignant transformation and to progress to HCC in very rare cases.

Thymic carcinomas and thymic neuroendocrine tumors: a tribute to Dr. Juan Rosai

Throughout his career, Dr. Juan Rosai greatly impacted our understanding of mediastinal tumors, both as a scientist and as a teacher. This review highlights his manifold contributions in the field of thymic carcinomas and thymic neuroendocrine tumors from a historical perspective.

Hepatotoxicity in Patients with Hepatocellular Carcinoma on Treatment with Immune Checkpoint Inhibitors

Simple Summary

Hepatitis is a relatively frequent immune-related adverse event in patients with hepatocellular carcinoma receiving immunotherapy, but risk factors and clinical course are unclear. Herein, we show that the development of high-grade hepatitis is associated with increased baseline ALT levels and infectious etiology of hepatocellular carcinoma (related to prior hepatitis B or C virus exposure). In addition, when resolved, high-grade hepatitis does not preclude treatment resumption and does not affect subsequent time to treatment failure. Analysis of baseline tumor specimens, at a preliminary level, suggests that biological features reminiscent of the hepatocellular carcinoma “immune class” could protect against high-grade hepatitis development, thereby warranting further investigation.

Abstract

Risk factors for hepatic immune-related adverse events (HIRAEs) in patients with advanced/unresectable hepatocellular carcinoma (HCC) treated with immune checkpoint inhibitors (ICIs) are unclear. We investigated: (i) clinical and morpho-pathological predictors of HIRAEs in 27 pretreatment tumor specimens, including surrogate biomarkers of the HCC immune class (based on intratumoral tertiary lymphoid structures, and glutamine synthase, CD3, and CD79 expression); and (ii) the relationship between HIRAE onset and subsequent treatment outcomes. Fifty-eight patients were included—20 (34%) received ICIs alone, and 38 (66%) received ICIs plus targeted agents as first- or further-line treatment. After a median time of 0.9 months (range, 0.4–2.7), nine patients (15.5%) developed grade ≥ 3 hepatitis, which was significantly associated with higher baseline ALT levels (p = 0.037), and an infectious HCC etiology (p = 0.023). ICIs were safely resumed in six out of nine patients. Time to treatment failure (TTF) was not significantly different in patients developing grade ≥ 3 hepatitis vs. lower grades (3.25 vs. 3.91 months, respectively; p = 0.81). Biomarker surrogates for the HCC immune class were not detected in patients developing grade ≥ 3 hepatitis. Grade ≥ 3 hepatitis has a benign course that does not preclude safe ICI reintroduction, without any detrimental effect on TTF.

Extracellular Signal-Regulated Kinase 5 Regulates the Malignant Phenotype of Cholangiocarcinoma Cells

BACKGROUND AND AIMS

Cholangiocarcinoma (CCA) is characterized by high resistance to chemotherapy and poor prognosis. Several oncogenic pathways converge on activation of extracellular signal-regulated kinase 5 (ERK5), whose role in CCA has not been explored. The aim of this study was to investigate the role of ERK5 in the biology of CCA.

APPROACH AND RESULTS

ERK5 expression was detected in two established (HuCCT-1 and CCLP-1) and two primary human intrahepatic CCA cell lines (iCCA58 and iCCA60). ERK5 phosphorylation was increased in CCA cells exposed to soluble mediators. In both HuCCT-1 and CCLP-1 cells, ERK5 was localized in the nucleus, and exposure to fetal bovine serum (FBS) further increased the amount of nuclear ERK5. In human CCA specimens, ERK5 mRNA expression was increased in tumor cells and positively correlated with portal invasion. ERK5 protein levels were significantly associated with tumor grade. Growth, migration, and invasion of CCA cells were decreased when ERK5 was silenced using specific short hairpin RNA (shRNA). The inhibitory effects on CCA cell proliferation, migration and invasion were recapitulated by treatment with small molecule inhibitors targeting ERK5. In addition, expression of the angiogenic factors VEGF and angiopoietin 1 was reduced after ERK5 silencing. Conditioned medium from ERK5-silenced cells had a lower ability to induce tube formation by human umbilical vein endothelial cells and to induce migration of myofibroblasts and monocytes/macrophages. In mice, subcutaneous injection of CCLP-1 cells silenced for ERK5 resulted in less frequent tumor development and smaller size of xenografts compared with cells transfected with nontargeting shRNA.

CONCLUSIONS

ERK5 is a key mediator of growth and migration of CCA cells and supports a protumorigenic crosstalk between the tumor and the microenvironment.

Development of a Deep-Learning Pipeline to Recognize and Characterize Macrophages in Colo-Rectal Liver Metastasis

Quantitative analysis of Tumor Microenvironment (TME) provides prognostic and predictive information in several human cancers but, with few exceptions, it is not performed in daily clinical practice since it is extremely time-consuming. We recently showed that the morphology of Tumor Associated Macrophages (TAMs) correlates with outcome in patients with Colo-Rectal Liver Metastases (CLM). However, as for other TME components, recognizing and characterizing hundreds of TAMs in a single histopathological slide is unfeasible. To fasten this process, we explored a deep-learning based solution. We tested three Convolutional Neural Networks (CNNs), namely UNet, SegNet and DeepLab-v3, with three different segmentation strategies, semantic segmentation, pixel penalties and instance segmentation. The different experiments are compared according to the Intersection over Union (IoU), a metric describing the similarity between what CNN predicts as TAM and the ground truth, and the Symmetric Best Dice (SBD), which indicates the ability of CNN to separate different TAMs. UNet and SegNet showed intrinsic limitations in discriminating single TAMs (highest SBD 61.34±2.21), whereas DeepLab-v3 accurately recognized TAMs from the background (IoU 89.13±3.85) and separated different TAMs (SBD 79.00±3.72). This deep-learning pipeline to recognize TAMs in digital slides will allow the characterization of TAM-related metrics in the daily clinical practice, allowing the implementation of prognostic tools.

Hepatocellular carcinoma: a clinical and pathological overview

HCC incidence rates have been rising in the past 3 decades and by 2025 > 1 million individuals will be affected annually. High-throughput sequencing technologies led to the identification of several molecular HCC subclasses that can be broadly grouped into 2 major subgroups, each characterized by specific morphological and phenotypical features. It is likely that this increasing knowledge and a more appropriate characterization of HCC at the pathological level will impact HCC patient management.

Risk Stratification of Cholangiocarcinoma Patients Presenting with Jaundice: A Retrospective Analysis from a Tertiary Referral Center

Simple Summary

Jaundice is a common clinical presentation of cholangiocarcinoma; however, the prognostic impact of this symptom is poorly understood. We retrospectively analyzed all consecutive cases presenting with jaundice between January 2010 and December 2017. During the study period, 200 patients (0.049% of all admissions) with CCA were identified. Most of them presented with advance disease, and median survival was 4.5 months. Age, stage of disease, presence of jaundice at the moment of diagnosis, and lack of concomitant viral hepatitis were associated with better survival. A nomogram was constructed that significantly predicts short term survival and could be used to tailor management.

Abstract

Cholangiocarcinomas (CCAs) are a heterogeneous group of tumors that arise from the biliary tract. Jaundice is a common clinical presentation; however, the prognostic impact of this symptom is poorly understood, and current management recommendations lack solid evidence. We aim to assess the clinical outcomes and predictive factors of CCA patients presenting with jaundice in the Emergency Room (ER). We retrospectively analyzed all consecutive ER cases presenting with jaundice between January 2010 and December 2017. During the study period, 403,766 patients were admitted to the ER, 1217 (0.3%) presented with jaundice, and in 200 (0.049%), the diagnosis was CCA. CCA cases increased during the study period (p for trend 0.026). Most of them presented with advance disease (stage III 46.5%, stage IV 43.5%) and median survival was 4.5 months (95% CI 3.4–6.0). Factors associated with better survival were age, stage of disease, presence of jaundice at the moment of diagnosis, and lack of concomitant viral hepatitis. A nomogram was constructed that significantly predicts 1-month, 6-month, and 1-year survival after patients’ admission. In conclusion, the majority of CCA patients presenting with jaundice to the ER have advanced disease and poor prognosis. Risk stratification of these patients can allow tailored management.

Mutation profile and immunoscore signature in thymic carcinomas: An exploratory study and review of the literature

Background

Significant efforts have been made to investigate the molecular pathways involved in thymic carcinogenesis. However, genetic findings have still not impacted clinical practice. The aim of this exploratory trial was to evaluate the immunoscore and molecular profile of a series of thymic carcinomas (TCs), correlating this data with clinical outcome.

Methods

Formalin‐fixed, paraffin‐embedded (FFPE) TC tissues were retrieved from our center archive. The immunoscore was evaluated according to Angell and Gallon. DNA was extracted from FFPE tumor samples and, when available, from adjacent histologically normal tissues. Next‐generation sequencing (NGS) was performed targeting hotspot regions of 50 oncogenes and tumor suppressor genes.

Results

A series of 15 TCs were analyzed. After a median follow‐up of 82.4 months, the median overall survival was 104.7 months. The immunoscore was >2 in 5/15 patients (33%). Among the investigated genes, absence of mutations was observed in 5/15 patients (33%), whereas three variants in 1/15 (6%) patient, two variants in 4/15 (26%) patients, and one variant in 5/15 patients (33%) were found. The most recurrently mutated genes were FGFR3 (five mutations) and CDKN2A (three mutations, two of which were nonsense). Patients with CDKN2A loss showed a statistically significantly worse survival (P = 0.0013), whereas patients with FGFR3 mutations showed a statistically significantly better survival (P = 0.048).

Conclusions

This study adds data to the few existing reports on the mutational landscape of TCs, providing the first comprehensive analysis to date. Here, we confirm the low rate of mutations in TCs and suggest FGFR3 and CDKN2A mutations as intriguing potential therapeutic targets.

Macrophage morphology correlates with single-cell diversity and prognosis in colorectal liver metastasis

It has long been known that in vitro polarized macrophages differ in morphology. Stemming from a conventional immunohistology observation, we set out to test the hypothesis that morphology of tumor-associated macrophages (TAMs) in colorectal liver metastasis (CLM) represents a correlate of functional diversity with prognostic significance. Density and morphological metrics of TAMs were measured and correlated with clinicopathological variables. While density of TAMs did not correlate with survival of CLM patients, the cell area identified small (S-TAM) and large (L-TAM) macrophages that were associated with 5-yr disease-free survival rates of 27.8% and 0.2%, respectively (P < 0.0001). RNA sequencing of morphologically distinct macrophages identified LXR/RXR as the most enriched pathway in large macrophages, with up-regulation of genes involved in cholesterol metabolism, scavenger receptors, MERTK, and complement. In single-cell analysis of mononuclear phagocytes from CLM tissues, S-TAM and L-TAM signatures were differentially enriched in individual clusters. These results suggest that morphometric characterization can serve as a simple readout of TAM diversity with strong prognostic significance.

Poorly-differentiated and undifferentiated sarcomas of the mediastinum: a bag of tricks

Mediastinum is a Pandora’s Box containing many different structures that can give origin to several cancer types. Our aims are to provide a general framework to make a diagnosis of an undifferentiated pleomorphic sarcoma and to highlight relevant immunohistochemical and molecular techniques that can help in the differential diagnosis. We, therefore, provide a simple three-step algorithmic approach to diagnose pleomorphic sarcoma, emphasizing the role of clinicopathological correlations and advocating for a “relative frequency” method, especially when the material for the diagnosis is scarce, as in small biopsies. In the first place, if clinical and/or radiological features make a non-sarcoma diagnosis more likely, it should be ruled in. Next, even if no specific non-sarcomatous diagnoses are suspected, they should always be ruled out. Lastly, since many sarcomas can have a pleomorphic appearance, specific entities should also be ruled out because their identification might affect prognosis and treatment. We then cover selected immunohistochemical and molecular ancillary tests that can come at hand in the diagnosis, highlighting the pros and cons; in particular the use and the limitations of H3K27me3 immunohistochemistry, the meaning of MDM2 amplification in the mediastinum and the implication of muscle differentiation—either smooth or skeletal—in sarcomas. The main take home messages are to always rule-out more frequent lesion first and always include clinical and radiological information in the diagnostic process.

Digital Pathology During the COVID-19 Outbreak in Italy: Survey Study

BACKGROUND

Transition to digital pathology usually takes months or years to be completed. We were familiarizing ourselves with digital pathology solutions at the time when the COVID-19 outbreak forced us to embark on an abrupt transition to digital pathology.

OBJECTIVE

The aim of this study was to quantitatively describe how the abrupt transition to digital pathology might affect the quality of diagnoses, model possible causes by probabilistic modeling, and qualitatively gauge the perception of this abrupt transition.

METHODS

A total of 17 pathologists and residents participated in this study; these participants reviewed 25 additional test cases from the archives and completed a final psychologic survey. For each case, participants performed several different diagnostic tasks, and their results were recorded and compared with the original diagnoses performed using the gold standard method (ie, conventional microscopy). We performed Bayesian data analysis with probabilistic modeling.

RESULTS

The overall analysis, comprising 1345 different items, resulted in a 9% (117/1345) error rate in using digital slides. The task of differentiating a neoplastic process from a nonneoplastic one accounted for an error rate of 10.7% (42/392), whereas the distinction of a malignant process from a benign one accounted for an error rate of 4.2% (11/258). Apart from residents, senior pathologists generated most discrepancies (7.9%, 13/164). Our model showed that these differences among career levels persisted even after adjusting for other factors.

CONCLUSIONS

Our findings are in line with previous findings, emphasizing that the duration of transition (ie, lengthy or abrupt) might not influence the diagnostic performance. Moreover, our findings highlight that senior pathologists may be limited by a digital gap, which may negatively affect their performance with digital pathology. These results can guide the process of digital transition in the field of pathology.

Rapid automated diagnosis of primary hepatic tumour by mass spectrometry and artificial intelligence

BACKGROUND AND AIMS

Complete surgical resection with negative margin is one of the pillars in treatment of liver tumours. However, current techniques for intra-operative assessment of tumour resection margins are time-consuming and empirical. Mass spectrometry (MS) combined with artificial intelligence (AI) is useful for classifying tissues and provides valuable prognostic information. The aim of this study was to develop a MS-based system for rapid and objective liver cancer identification and classification.

METHODS

A large dataset derived from 222 patients with hepatocellular carcinoma (HCC, 117 tumours and 105 non-tumours) and 96 patients with mass-forming cholangiocarcinoma (MFCCC, 50 tumours and 46 non-tumours) were analysed by Probe Electrospray Ionization (PESI) MS. AI by means of support vector machine (SVM) and random forest (RF) algorithms was employed. For each classifier, sensitivity, specificity and accuracy were calculated.

RESULTS

The overall diagnostic accuracy exceeded 94% in both the AI algorithms. For identification of HCC vs non-tumour tissue, RF was the best, with 98.2% accuracy, 97.4% sensitivity and 99% specificity. For MFCCC vs non-tumour tissue, both algorithms gave 99.0% accuracy, 98% sensitivity and 100% specificity.

CONCLUSIONS

The herein reported MS-based system, combined with AI, permits liver cancer identification with high accuracy. Its bench-top size, minimal sample preparation and short working time are the main advantages. From diagnostics to therapeutics, it has the potential to influence the decision-making process in real-time with the ultimate aim of improving cancer patient cure.

Accuracy of fine-needle aspiration cytology in detecting cervical node metastasis after radiotherapy: Systematic review and meta-analysis

PURPOSE

To define the accuracy of fine-needle aspiration cytology (FNAC) in diagnosing persistent or recurrent neck metastases in previously irradiated patients.

METHODS

The study was performed according to the PRISMA-DTA guidelines.

RESULTS

A total of 382 FNACs were used for calculation of diagnostic accuracy parameters. The overall pooled sensitivity and specificity in detecting malignant nodes were 69.1% (95% CI: 56.3%-80.7%; I² = 79.5%) and 84.2% (95% CI: 71.8%-93.5%; I² = 87.0%), respectively. Cumulative diagnostic odds ratio (DOR) was 16.54 (95% CI: 4.89-38.99; I² = 65.8%), while cumulative positive and negative likelihood ratio (PLR and NLR) were 5.4 (95% CI: 2.3-11.2) and 0.37 (95% CI: 0.22-0.54), respectively.

CONCLUSIONS

FNAC alone could not guide the decision to perform a salvage neck dissection in previously irradiated patients, but its results should be assessed in relation to the specific clinical context.

Is the outcome after hepatectomy for transitional hepatocholangiocarcinoma different from that of hepatocellular carcinoma and mass-forming cholangiocarcinoma? A case-matched analysis

Hepatocholangiocarcinoma (HCC-CC) is a rare malignancy containing features of both hepatocellular carcinoma (HCC) and mass-forming cholangiocarcinoma (MFCCC), of which the outcome after hepatectomy remains to be clarified. The aim of this study was to analyze the characteristics and outcomes of patients with transitional HCC-CC and compare them with those of patients with HCC and MFCCC. Our prospectively maintained database was queried, and 14 transitional HCC-CC patients were identified over a total of 406 consecutive hepatic resections. A 1:1:1 match was performed with HCC and MFCCC patients operated in the same period. A total of 42 patients were matched according to tumor stage (T1-2-3, N0, M0), number of tumors, R0 resection, no 90-day mortality, and follow-up. Primary endpoints were disease-free survival (DFS) and overall survival (OS). Disease-free survival rates at 1-, 3-, and 5-year were 71.4%, 57.1%, 35.7% for transitional HCC-CC patients; 85.7%, 40.4%, 10.1% for HCC patients; 85.1%, 34.0%, 22.7% for MFCCC patients (5-year DFS: HCC-CC vs. HCC, p = 0.575; HCC-CC vs. MFCCC, p = 0.766, respectively). Similarly, OS rates at 1-, 3-, and 5-year were 92.9%, 71.4%, 64.3% for transitional HCC-CC patients; 100%, 64.3%, 41.7% for HCC patients; 100%, 54.5%, 43.6% for MFCCC patients (5-year OS: HCC-CC vs. HCC, p = 0.891; HCC-CC vs. MFCCC, p = 0.673, respectively). When accurately matched with respect to tumor burden, transitional HCC-CC patients show similar outcomes to those of HCC and MFCCC patients. Further evaluations of differences in tumor biology are necessary to better characterize the prognosis of transitional HCC-CC patients.

Early Hepatic Lesions Display Immature Tertiary Lymphoid Structures and Show Elevated Expression of Immune Inhibitory and Immunosuppressive Molecules

PURPOSE

The impact of tertiary lymphoid structures (TLS) in hepatocellular carcinoma (HCC) progression is being extensively investigated. However, their presence during the early steps of human liver carcinogenesis remains unknown. We thus aimed to determine whether TLS are induced in preneoplastic/early hepatic lesions (EHL), and whether they are associated with a particular immune profile.

EXPERIMENTAL DESIGN

A series of 127 EHLs (low/high-grade dysplastic nodules, early HCC, and small and progressed HCC) was included in the study. TLSs were investigated by pathologic reviewing. Densities of immune cells were assessed using IHC. A subset of lesions was microdissected and gene expression profiling was performed with a custom NanoString panel.

RESULTS

Compared with surrounding cirrhotic nodules, EHL of all stages displayed increased densities of T cells, B cells, and dendritic cells. Immature TLSs were identified in 24% of EHL. Gene expression profiling identified a subset of EHL with elevated mRNA levels of various cytokines involved in immune cells' recruitment and TLS induction. This subgroup of EHL also showed overexpression of genes related to T- and B-cells' activation and antigen presentation, as well as those related to immunosuppression and immune exhaustion.

CONCLUSIONS

Local immune activation occurs in the very early steps of liver carcinogenesis; however, it may not be fully efficient and paradoxically favor immune evasion and progression to full-blown HCC. These results have implications for the development of anti-HCC chemopreventive strategies in cirrhotic patients.

Impact of RAS mutations on the immune infiltrate of colorectal liver metastases: A preliminary study

Kirsten rat sarcoma viral oncogene homolog KRAS proto-oncogene is the most common altered gene in colorectal cancer (CRC). Determining its mutational status, which is associated with worse prognosis and resistance to anti-epidermal growth factor receptor (EGFR) inhibitors, is essential for managing patients with CRC and colon liver metastases (CLM). Emerging studies highlighted the relationship of KRAS-mutated cancers and tumor microenvironment components, mainly with T cells. The aim of this study was to analyze the relationship of CLM immune cell infiltrate with KRAS mutational status. We performed a retrospective study on paraffin-embedded CLM tissue sections from patients surgically resected at the Department of Hepatobiliary and General Surgery of Humanitas Clinical and Cancer Center. We studied the distribution of lymphocytes (CD3+ cells), macrophages (CD163+), and neutrophils (CD66b+) in CLM tumoral and peritumoral area. Percentage of positive cells was correlated with tumor macroscopic characteristic, clinical aspects, and KRAS mutation. We observed a significant increase in CD66b+ cells in the peritumoral area in patients KRAS-mutated compared to KRAS wild-type patients. Percentages of lymphocytes and macrophages did not show significant differences. Further, neutrophils were found to be significantly increased also in the bloodstream of KRAS-mutated patients, indicating increased mobilization of neutrophils and recruitment in the CLM site. In conclusion, this study reveals a new intriguing aspect of the peritumoral microenvironment, which could pave the way for new prognostic and predictive markers for patient stratification.

Abstract P5-04-07: Defining T cell dysfunctionality in breast cancer by single cell analysis: Implications for immunotherapy

Background Despite the well-known association between extensive lymphocytic infiltration in breast cancer (BC), good prognosis, and high response rates to neoadjuvant chemotherapy (CT), pathologic evaluation of tumor infiltrating lymphocytes (TILs) is currently not routine and a deep understanding of the properties of TILs, remain largely unfilled. So far, only in triple-negative (TN), PD-L1 positive BCs it has been possible to demonstrate a survival benefit with immunotherapy plus CT, thereby making the definition of possible immunotherapeutic targets across all biological subtypes a fundamental requirement. Material and methods Single-cell RNA-sequencing (scRNAseq) data from 8 BCs were downloaded from Gene Expression Omnibus dataset (GSE114725), obtaining CD45+ single cells only from the tumoral compartment. scRNAseq-guided high-dimensional profiling by 27-parameter FACS was then applied to a large cohort (n=54, including luminal-like, TN and HER2+ BCs) of early BC patients surgically treated at our Institution. We simultaneously profiled the peripheral blood, the normal and tumoral tissue from each patient and acquired using FACS Symphony A5 flow cytometer (BD Biosciences). Flow Cytometry Standard (FCS) 3.0 files were imported into FlowJo software v9, and analyzed by standard gating to remove aggregates and dead cells, and subsequently imported in FlowJo v10, biexponentially transformed, and exported for further analysis in R by a custom-made script, using an ad-hoc pipeline. Data were analyzed using the Phenograph unbiased algorithm coded in the cytofkit package. Data were further analyzed in FlowJo to determine the frequency of positive cells for each marker and the corresponding median fluorescence intensity (MFI). These values were multiplied to derive the integrated MFI; hierarchical metaclustering of all samples, based on the frequency of Phenograph clusters, was performed in R based on the Euclidean distance and Ward-linkage. Pearson correlation analysis was used to investigate the relationship between CD8+ and CD4+ clusters. Results Our scRNA-guided informative 27-colors flow cytometry panel included antibodies to define not only different lymphocyte subpopulations, but also different stages of T lymphocytes: differentiation and memory maturation (CCR7, CD45RA), activation status (HLA-DR), cytotoxicity (GZMK, GZMB), exhaustion (PD-1, TIGIT) and tissue residency (CD69, CD103). Focusing on CD8+ T cells, we observed, as expected, bona fide naïve T cells to be virtually absent at the tumor site and enriched in peripheral blood, while cytotoxic and effector memory cells were enriched in the tumor compartment. Of note, we identified a population of tissue resident memory T cells (Trm) CD69+ CD103+, CD39+, specifically enriched in the tumor, that could be further subdivided into a HLA-DR+ CD127- and a HLA-DR- CD127+ subpopulation. Interestingly, the HLA-DR+ subset exhibited more exhaustion markers (PD-1hi, TIGIT+, NKG2A+) and was significantly positively correlated with CD4+ regulatory T cells. We speculated, and deeply investigated by bulk RNA-seq, that these two subsets of Trm might represent different maturation states and that they could be reinvigorated targeting highly expressed inhibitory molecules using approved (e.g., PD-1) together with newly identified (e.g., NKG2A) immunotherapeutics. Moreover, as no difference was observed in the relative distribution of Phenograph clusters, our data may be applied to revert acquired immune escape mechanisms in all different BC biological subtypes. Conclusions We identified, among Trm CD69+ CD103+, tumor-specific CD39+, PD1+ exhausted population, novel dysfunctional NKG2A+ T cells previously not characterized in BC. This population is of extreme interest to characterize a novel potential immunotherapeutic target.

Citation Format: Agnese Losurdo, Caterina Scirgolea, Emilia Mazza, Valentina Errico, Bethania Fernandes, Luca Di Tommaso, Andrea Sagona, Karolina Pilipow, Rosalba Torrisi, Giovanna Masci, Rita De Sanctis, Elisa Agostinetto, Alberto Testori, Corrado Tinterri, Massimo Roncalli, Armando Santoro, Enrico Lugli. Defining T cell dysfunctionality in breast cancer by single cell analysis: Implications for immunotherapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-04-07.

Vessels Encapsulating Tumor Clusters (VETC) Is a Powerful Predictor of Aggressive Hepatocellular Carcinoma

We investigated the clinical significance of a vascular growth pattern of hepatocellular carcinoma (HCC), the vessels that encapsulate tumor clusters (VETC), previously linked to HCC metastatic dissemination. VETC was assessed in a large multi-institutional cohort of 541 resected HCCs from Italy, Korea and Japan, and matched against a full spectrum of clinical and pathological variables. The VETC phenotype (defined as ≥ 55% tumor area by CD34 immunostaining) was easily reproducible and reliably detectable in whole sections and small-sized tissues of tissue microarray. VETC HCCs represented 18.9% of the whole series, the lowest proportion occurring in the cohort with smallest tumors (8.7%, Japanese series). VETC was significantly associated with several clinical and pathological features such as high alfa-fetoprotein (AFP) level, tumor size greater than 5 cm, poor differentiation, macrotrabecular pattern, less compact pattern, less inflammatory infiltrates, and frequent microvascular invasion. VETC was associated with early recurrence (hazard ratio [HR]: 1.52 [1.06-2.19], P = 0.023), disease-free survival (HR: 1.66 [1.21-2.27], P = 0.002), and overall survival (HR: 2.26 [1.37-3.72], P = 0.001) at multivariable analysis. VETC affected the survival in HCC patients stratified for etiology (hepatitis C virus/hepatitis B virus), vascular invasion, and specific molecular phenotypes (β-catenin/GS+). This distinct vascular pattern was enriched in the recently reported macrotrabecular massive HCC subtype, which was seen in 7.8% (42 of 541) of patients and associated with high AFP levels and poor differentiation. Conclusion: The VETC pattern was found to be easily detectable in a consistent fraction of HCC and a powerful pathological finding affecting survival. This study suggests that the heterogeneous pattern of angiogenesis is involved in HCC behavior.

Tumor-Infiltrating Lymphocytes and Macrophages in Intrahepatic Cholangiocellular Carcinoma. Impact on Prognosis after Complete Surgery

BACKGROUND

Immune infiltrate impacts prognosis of several tumors. To assess the prognostic impact of tumor-infiltrating lymphocytes and macrophages in patients undergoing resection for intrahepatic cholangiocellular carcinoma (ICC).

METHODS

All consecutive patients undergoing surgery for ICC between 2008 and 2016 were considered. Inclusion criteria were complete resection and follow-up > 12 months. Tissue sections were immunostained for CD3+, CD4+, CD8+, Foxp3+, and CD68+. The number of positive cells was quantified using a computer-aided image analysis system. Different cut-off values were tested as predictors of overall survival (OS).

RESULTS

Fifty-three patients were analyzed. ICC were T1 in 28 patients, multifocal in 11, and N+ in 13. After a median follow-up of 42 months, 5-year OS was 52.1%. The following immune infiltrate values were associated with better OS: CD3+ > 0.10% (5-year OS 63.3% vs. 13.6% if ≤ 0.10%, p = 0.001); CD8+ > 0.10% (56.2% vs. 28.6% if ≤ 0.10%, p = 0.051); Foxp3+ absent (59.4% vs. 16.0% if present, p = 0.049). CD4+ and CD68+ infiltrates were not associated with OS. Three-year OS rates in patients with 0, 1, and ≥ 2 negative prognostic factors were 73.6%, 47.3%, and 14.3%, respectively (p < 0.001). CD3+ infiltrate stratified prognosis in T1 tumors (3-year OS 71.7% if CD3+ > 0.10% vs. 14.3% if ≤ 0.10%, p < 0.001).

CONCLUSIONS

Tumor-infiltrating lymphocytes are associated with prognosis of ICC patients after complete surgery. CD3+ and CD8+ infiltrate is associated with higher survival and lower recurrence risk, while Foxp3+ infiltrate is associated with worse prognosis. CD3+ infiltrate allows refining prediction of prognosis in early tumors.

Role of liver biopsy in hepatocellular carcinoma

The role of liver biopsy in the diagnosis of hepatocellular carcinoma (HCC) has been challenged over time by the ability of imaging techniques to characterize liver lesions in patients with known cirrhosis. In fact, in the diagnostic algorithm for this tumor, histology is currently relegated to controversial cases. Furthermore, the risk of complications, such as tumor seeding and bleeding, as well as inadequate sampling have further limited the use of liver biopsy for HCC management. However, there is growing evidence of prognostic and therapeutic information available from microscopic and molecular analysis of HCC and, as the information content of the tissue sample increases, the advantages of liver biopsy might modify the current risk/benefit ratio. We herein review the role and potentiality of liver biopsy in the diagnosis and management of HCC. As the potentiality of precision medicine comes to the management of HCC, it will be crucial to have rapid pathways to define prognosis, and even treatment, by identifying the patients who could most benefit from target-driven therapies. All of the above reasons suggest that the current role of liver biopsy in the management of HCC needs substantial reconsideration.

Clinical Application of a Real-Time Telepathology System for Frozen Section Diagnosis in Comparison With Optical Microscope

Background: The imbalance between the increasing demand of highly specialized service and the reduction of specialists able to release this service is a global challenge for Pathology. This situation applies also to the setting of intra-operatory diagnostic: here the broad presence of Surgical divisions contrasts with the contraction of Pathology departments, progressively concentrated in few hospitals. The use of e-pathology device, such as remote-control microscopes, offers a possible solution to this imbalance. Aim: To prove the non-inferiority of function of a remote-control, real-time microscope named Nano-Eye Device (NED) with the optical microscope (OM) for intra-operatory histological diagnosis. Methods: The study was designed into two phases: discovery and validation. During the discovery phase features influencing the process of adaptation to NED were investigated in detail, focusing on the turnaround time (TAT). Validation phase investigated the diagnostic concordance between NED and OM; as well as sensitivity, specificity, and accuracy of NED in intra-operatory histological diagnosis. Results: During the discovery phase 250 cases were examined. TAT of NED was longer than that of OM (112 ± 89.8 vs. 36 ± 37.9 s) and influenced by the difficulty of the specimen, age of pathologist and the type of the specimen. In the validation phase (185 cases) TAT of NED reduced significantly to 92 ± 86.3 s (p: 0.01). NED showed a concordance rate of 98% with OM; the sensitivity (95.65%), specificity (100%), and diagnostic accuracy (98.87%) of NED were equal to that of OM. NED failed to work in 6% during the discovery phase and 4% in the validation. Conclusions: Taken as a whole, the functionality of NED is comparable to OM. It can be the alternative choice for hospital lacking on-site pathology services and one of the tool of e-pathology.

Pancreatic Neuroendocrine Tumours: The Role of Endoscopic Ultrasound Biopsy in Diagnosis and Grading Based on the WHO 2017 Classification

BACKGROUND

One of the controversial issues in the diagnosis of pancreatic neuroendocrine tumours (pNETs) is the accurate prediction of their clinical behaviour.

OBJECTIVES

The aim of the study was to evaluate the role of endoscopic ultrasound (EUS) biopsy in the diagnosis and grading of pNETs in a certified ENETS Center.

METHODS

A prospectively maintained database of EUS biopsy procedures was retrospectively reviewed to identify all consecutive patients referred to a certified ENETS Center with a suspicion of pNET between June 2014 and April 2017. The cytological and/or histological specimens were stained and the Ki-67 labeling index was evaluated. In patients undergoing surgery, the grade obtained with EUS-guided biopsy was compared with the final histological grade. The grade was evaluated according to the 2017 WHO classifications and grading.

RESULTS

The study population included 59 patients. EUS biopsy material reached an adequacy of 98.3% and was adequate for Ki-67 evaluation in 84.7% of cases. Twenty-nine patients (49.2%) underwent surgery. Of these, 25 patients had Ki-67 evaluated on EUS biopsy: the agreement between EUS biopsy grading and surgical specimen grading was 84%.

CONCLUSION

EUS biopsy is an accurate method for the diagnosis and grading of pNETs based on the WHO 2017 Ki-67 labelling scheme.

Computer-aided assessment of the extra-cellular matrix during pancreatic carcinogenesis: a pilot study

BACKGROUND

A hallmark of pancreatic ductal adenocarcinoma is the desmoplastic reaction, but its impact on the tumor behavior remains controversial. Our aim was to introduce a computer -aided method to precisely quantify the amount of pancreatic collagenic extra-cellular matrix, its spatial distribution pattern, and the degradation process.

METHODS

A series of normal, inflammatory and neoplastic pancreatic ductal adenocarcinoma formalin-fixed and paraffin-embedded Sirius red stained sections were automatically digitized and analyzed using a computer-aided method.

RESULTS

We found a progressive increase of pancreatic collagenic extra-cellular matrix from normal to the inflammatory and pancreatic ductal adenocarcinoma. The two-dimensional fractal dimension showed a significant difference in the collagenic extra-cellular matrix spatial complexity between normal versus inflammatory and pancreatic ductal adenocarcinoma. A significant difference when comparing the number of cycles necessary to degrade the pancreatic collagenic extra-cellular matrix in normal versus inflammatory and pancreatic ductal adenocarcinoma was also found. The difference between inflammatory and pancreatic ductal adenocarcinoma was also significant. Furthermore, the mean velocity of collagenic extra-cellular matrix degradation was found to be faster in inflammatory and pancreatic ductal adenocarcinoma than in normal.

CONCLUSION

These findings demonstrate that inflammatory and pancreatic ductal adenocarcinomas are characterized by an increased amount of pancreatic collagenic extra-cellular matrix and by changes in their spatial complexity and degradation. Our study defines new features about the pancreatic collagenic extra-cellular matrix, and represents a basis for further investigations into the clinical behavior of pancreatic ductal adenocarcinoma and the development of therapeutic strategies.

Is R1 vascular hepatectomy for hepatocellular carcinoma oncologically adequate? Analysis of 327 consecutive patients

BACKGROUND

R1 vascular resection for liver tumors was introduced in the early twenty-first century. However, its oncologic adequacy remains controversial. The aim of this study was to determine the oncologic adequacy of R1 vascular hepatectomy in hepatocellular carcinoma patients.

METHODS

A prospective cohort of patients with hepatocellular carcinoma resected between the years 2005 and 2015 was reviewed. R0 was any resection with a minimum 1 mm of negative margin. R1 vascular was any resection with tumor exposure attributable to the detachment from major intrahepatic vessel. R1 parenchymal was any resection with tumor exposure at parenchymal margin. The end points were the calculation of the local recurrence of R0, R1 parenchymal, and R1 vascular hepatectomy and their prognostic significances.

RESULTS

We analyzed 327 consecutive patients with 532 hepatocellular carcinoma and 448 resection areas. We found that 205 (63%) resulted R0, 56 (17%) resulted R1 parenchymal, 50 (15%) resulted R1 vascular, and 16 (5%) resulted both R1 parenchymal and R1 vascular. After a median follow-up of 33.5 months (range 6.1-107.6), the 5-year overall survival rates were 54%, 30%, 65%, and 36%, respectively for R0, R1 parenchymal, R1 vascular, and R1 parenchymal + R1 vascular (P = .031). Local recurrence rates were 3%, 14%, 4%, and 19%, respectively for R0, R1 parenchymal, R1 vascular, and R1 parenchymal + R1 vascular (P = .001) per patient, and 4%, 4%, 12%, and 18%, respectively for R0, R1 vascular, R1 parenchymal, and R1 parenchymal + R1 vascular (P = .001) per resection area. At multivariate analysis R1 parenchymal and R1 vascular + R1 parenchymal were independent detrimental factors.

CONCLUSION

R1 vascular hepatectomy for hepatocellular carcinoma is not associated with increased local recurrence or decreased survival. Thus, detachment of hepatocellular carcinoma from intrahepatic vessels should be considered oncologically adequate.

Prospective Evaluation of Intrahepatic Microscopic Occult Tumor Foci in Patients with Numerous Colorectal Liver Metastases

BACKGROUND

Patients with numerous colorectal liver metastases (CLM) have high risk of early recurrence after liver resection (LR). The presence of intrahepatic occult microscopic metastases missed by imaging has been hypothesized, but it has never been assessed by pathology analyses.

METHODS

All patients with > 10 CLM who underwent LR between September 2015 and September 2016 were considered. A large sample of liver without evidence of disease ("healthy liver") was taken from the resected specimen and sent to the pathologist. One mm-thick sections were analyzed. Any metastasis, undetected by preoperative and intraoperative imaging, but identified by the pathologist was classified as occult microscopic metastasis.

RESULTS

Ten patients were prospectively enrolled (median number of CLM n = 15). In a per-lesion analysis, the sensitivity of computed tomography and magnetic resonance imaging was 91 and 98% respectively. The pathology examination confirmed all the CLM. All patients had an adequate sample of "healthy liver" (median number of examined blocks per sample n = 14 [5-33]). No occult microscopic metastases were detected. After a median follow-up of 15 months, 5 patients were disease-free. Recurrence was hepatic and bilobar in all patients.

CONCLUSIONS

Clinically relevant occult microscopic disease in patients with numerous CLM is excluded. These results support the indication to resection in such patients and exclude the need for de principe major hepatectomy to increase the completeness of surgery.

The Shifting Paradigm of Prognostic Factors of Colorectal Liver Metastases: From Tumor-Centered to Host Immune-Centered Factors

The determinants of prognosis in patients with colorectal liver metastases (CLM) have been traditionally searched among the tumoral factors, either of the primary colorectal tumor or of the CLM. While many different scoring systems have been developed based on those clinic-pathological factors with disparate results, there has been the introduction of genetic biological markers that added a theranostic perspective. More recently, other important elements, such as those factors related to the host immune system, have been proposed as determinants of prognosis of CLM patients. In the present work, we review the current prognostic factors of CLM patients as well as the burgeoning shifting paradigm of prognostication that relies on the host immune system.

B lymphocytes limit senescence-driven fibrosis resolution and favor hepatocarcinogenesis in mouse liver injury

Hepatocellular carcinoma (HCC) is a frequent neoplasia and a leading cause of inflammation-related cancer mortality. Despite that most HCCs arise from persistent inflammatory conditions, pathways linking chronic inflammation to cancer development are still incompletely elucidated. We dissected the role of adaptive immunity in the Mdr2 knockout (Mdr2-/- ) mouse, a model of inflammation-associated cancer, in which ablation of adaptive immunity has been induced genetically (Rag2-/- Mdr2-/- and μMt-Mdr2-/- mice) or with in vivo treatments using lymphocyte-specific depleting antibodies (anti-CD20 or anti-CD4/CD8). We found that activated B and T lymphocytes, secreting fibrogenic tumor necrosis factor alpha (TNFα) and other proinflammatory cytokines, infiltrated liver of the Mdr2-/- mice during chronic fibrosing cholangitis. Lymphocyte ablation, in the Rag2-/- Mdr2-/- and μMt-Mdr2-/- mice, strongly suppressed hepatic stellate cell (HSC) activation and extracellular matrix deposition, enhancing HSC transition to cellular senescence. Moreover, lack of lymphocytes changed the intrahepatic metabolic/oxidative state, resulting in skewed macrophage polarization toward an anti-inflammatory M2 phenotype. Remarkably, hepatocarcinogenesis was significantly suppressed in the Rag2-/- Mdr2-/- mice, correlating with reduced TNFα/NF-κB (nuclear factor kappa B) pathway activation. Ablation of CD20+ B cells, but not of CD4+ /CD8+ T cells, in Mdr2-/- mice, promoted senescence-mediated fibrosis resolution and inhibited the protumorigenic TNFα/NF-κB pathway. Interestingly, presence of infiltrating B cells correlated with increased tumor aggressiveness and reduced disease-free survival in human HCC.

CONCLUSION

Adaptive immunity sustains liver fibrosis (LF) and favors HCC growth in chronic injury, by modulating innate components of inflammation and limiting the extent of HSC senescence. Therapies designed for B-cell targeting may be an effective strategy in LF. (Hepatology 2018;67:1970-1985).