Tissue microarrays for high-throughput molecular profiling of tumor specimens

GATA3 amplification is associated with high grade disease in non-invasive urothelial bladder cancer but unrelated to patient prognosis

PURPOSE

We aimed to assess the impact of GATA3 binding protein (GATA3) gene copy number alterations on tumor aggressiveness, patient prognosis, and GATA3 protein expression in a large urothelial bladder cancer cohort.

METHODS

A tissue microarray containing over 2,700 urothelial bladder cancers (pTa-pT4) was analyzed retrospectively using dual-labeling fluorescence in-situ hybridization (FISH) with probes for GATA3 (10p14) and centromere 10. GATA3 copy number gains were categorized as GATA3 elevation (ratio GATA3/centromere ≥ 2/≤4), low-level amplification (ratio > 4/≤12), and high-level amplification (ratio > 12) and deletions were divided between homozygous and heterozygous.

RESULTS

GATA3 copy number gain was detected in 9.9% of 2,213 interpretable tumors, including 2.0% with GATA3 elevation, 3.2% with low-level amplification, and 4.7% with high-level amplification. The frequency of high-level amplification increased from pTa G2 low (0%) to pTa G3 tumors (12% [CI 0.07;0.21]; p < 0.0001 pTa G2 low vs. pTaG2 high) but decreased in advanced-stage carcinomas pT2-4 with 5.4% [CI 0.07;0.21] (p < 0.0001, pTa vs. pT2-4). In muscle-invasive carcinomas, GATA3 amplification was not linked to tumor aggressiveness or patient survival. Overall, no homozygous GATA3 deletion was detected and heterozygous GATA3 deletion was only observed in 1.1%; of 1,432 pT2-4 tumors without any association to cancer progression. While GATA3 copy number was significantly correlated with GATA3 expression (p < 0.0001), the relationship was not strong. Only 2.3% of GATA3-negative cancers had a deletion, and 42.1% of strong GATA3-expressing cancers exhibited high-level amplification.

CONCLUSION

High-level GATA3 amplification is common in urothelial bladder cancer and correlates with grade progression in pTa tumors, while GATA3 deletion is rare. Neither amplification nor deletion appears to be the primary driver of GATA3 expression dysregulation.

CLINICAL TRIAL NUMBER

Not applicable.

IMMUNOREACT 8: Immune markers of local tumor spread in patients undergoing transanal excision for clinically N0 rectal cancer

BACKGROUND

Transanal excision of rectal cancer can be considered the definitive surgical treatment if the depth spread is T1 or lower, and the lesion is completely included within the resection margin. This study aims to analyze the immune microenvironment in healthy rectal mucosa as a possible predictor of tumor infiltration depth, lateral tumor spread, and recurrence of rectal cancer after transanal local excision.

METHODS

This study is a subanalysis of data from the IMMUNOREACT 1 and 2 trials (NCT04915326 and NCT04917263, respectively) including all the patients who underwent transanal excision of rectal cancer. This multicentric study collected healthy mucosa surrounding the neoplasms of patients with rectal cancer. A panel of immune markers was investigated at immunohistochemistry: CD3, CD4, CD8, CD8β, Tbet, FoxP3, PD-L1, MSH6, and PMS2 and CD80. Flow cytometry determined the proportion of epithelial cells expressing CD80, CD86, CD40, HLA ABC or HLA DR and the proportion of activated CD8+ T cells, CD4+ Th1 cells, and Treg.

RESULTS

Receiver operating characteristic curve analysis for predicting deep tumor spread showed an area under the curve of 0.70 (95% confidence interval: 0.60-0.80) for CD25+FoxP3+ cell rate and 0.74 (95% confidence interval: 0.53-0.92) for CK+CD86+ cell rate. Receiver operating characteristic curve analysis for predicting lateral tumor spread showed an area under the curve of 0.82 (95% confidence interval: 0.61-0.99) for CD8+CD38+ MFI, 0.96 (95% confidence interval: 0.85-0.99) for CD8β infiltration, and 0.97 (95% confidence interval: 0.87-0.99) for CK+HLAabc+ cell rate. Receiver operating characteristic curve analysis for predicting recurrence showed an area under the curve of 0.93 (95% confidence interval: 0.76-0.99) for CD8+CD38+ MFI and 0.94 (95% confidence interval: 0.78-0.99) for CD8+CD28+ MFI. Low CD8+CD38+ MFI and low CD8+CD28+ MFI were associated with shorter disease-free survival (P = .025 and P = .021, respectively).

CONCLUSION

Our study showed that the association between the high proportion of epithelial cells acting as presenting cells and deep or lateral tumor spread may be explained by the presence of a greater tumor load at the site. Moreover, it showed that weak activation of CD8+ T cells within the rectal mucosa is associated with lateral tumor spread and eventually a higher recurrence rate. The mucosal level of CD8β infiltration detected at immunohistochemistry might be tested as a marker of lateral tumor spread and potentially translated into clinical practice.

Impact of CCND1 amplification on the prognosis of hormone receptor-positive, HER2-negative breast cancer patients-correlation of clinical and pathological markers

PURPOSE

The cyclin D1 gene (CCND1) encodes a key cell-cycle regulatory protein. Resistance to endocrine therapy is reportedly observed more often in patients with CCND1-amplified tumors. CCND1 amplification is known to be a driving event in breast cancer, but contradictory findings are reported for its association with prognosis. This study therefore investigated the prognostic value of CCND1 amplification in hormone receptor (HR)-positive breast cancer patients.

METHODS

A cohort of 894 unselected breast cancer patients from the Bavarian Breast Cancer Cases and Controls (BBCC) study was included. The CCND1 amplification rate was evaluated in tissue microarrays using fluorescence in situ hybridization. A CCND1/CEP11 ratio ≥ 2.0 was considered amplified. Statistical analysis was conducted on cases with ratios based on a range of 20-100 nuclei analyzed per case. A univariable Cox regression model was fitted with disease-free survival (DFS) and overall survival (OS).

RESULTS

CCND1 gene status was assessable in 511 patients. The CCND1 amplification rate was 12.9% (66 patients). Most patients with CCND1 amplification had luminal B-Like-(51.5%, n = 34) or luminal A-Like tumors (25.8%, n = 17), 13 patients with HER2-positive disease (19.7%) and only two patients had triple-negative tumors (3.0%). Survival analysis, focused on HR-positive, HER2-negative patients, showed no statistically significant differences in the DFS and OS with and without CCND1 amplification (P = 0.20 and 0.14, respectively, in the unadjusted analysis).

CONCLUSIONS

CCND1 amplification is a recurring event in breast cancer, occurring most frequently in luminal B-like and HER2-amplified subtypes. A trend toward less favorable outcomes was observed among CCND1-amplified HR-positive, HER2-negative tumors.

How to Write a Pathology Research Paper-Basic Principles and Beyond-A Primer for Residents

Medical writing is an art but still it is usually not in the curriculum of medical students. With the beginning of scientific activity during residency, many perceive this gap increasingly, and stay behind their own expectations in their scientific productivity. Many universities offer courses to teach scientific writing and many books and article address this void, but in real life the main work to carve a readable paper out of a pile of unsorted data remains often in the hands of the scientific supervisors. This little paper tries to address this issue with a focus on typical pathology related subjects by outlining the structure of a paper and explaining typical dos and don'ts of crafting a publishable scientific paper as a pathology resident.

Virtual Tissue Microarrays for Validating Digital Biomarker Analysis in Colorectal Carcinomaf

Tissue microarrays (TMAs) are used for high-throughput biomarker discovery and validation. Although TMAs have numerous advantages, they may not always be representative of the tissue heterogeneity present in whole tissue sections (WTS) leading to inadequate biomarker quantification. In this pilot study, we studied biomarker expression in 50 randomly selected colorectal cancers and 36 microsatellite unstable cases with or without BRAF variants. We used virtual TMAs to determine the minimum number of tissue cores needed to quantify biomarkers with the same precision as when using WTS. Paraffin sections were immunohistochemically stained for markers of T cells, B cells, cancer-associated fibroblasts, and macrophages. Digitized WTS were divided into tumor center (TC) and invasive margin regions. The minimum number of virtual TMA cores in each region was determined by Bland-Altman plots with 95% limits of agreement. Bland-Altman plots showed substantial disagreement between TMAs and WTS, being highest for 3 cores and decreasing with increasing core numbers. However, even when using 8 cores, the limits of agreement between TMA and WTS were wide, indicating a high degree of measuring uncertainty using TMAs. When using 3 or 4 cores, TMAs underestimated the expression of all the biomarkers in the TC; similarly, levels of macrophage markers in the TC, and levels of B cells in both the TC and the invasive margin remained considerably underestimated, even when using the maximum number of cores possible. However, 3 cores were sufficient to adequately classify biomarkers into categoric low and high expression groups. Microsatellite unstable tumors were characterized by high heterogeneity, which was further increased in the presence of BRAF variant(s). The virtual TMA technique is a useful method to establish the minimum number of cores to be included when constructing tumor TMAs for biomarker analysis. Our results emphasize the importance of TMA validation for a specific biomarker prior to conducting larger clinical studies.

Prognostic value of immune biomarkers in melanoma loco-regional metastases

The prognosis for patients with melanoma loco-regional metastases is very heterogenous. Adjuvant PD-L1-inhibitors have improved clinical outcome for this patient group, but the prognostic impact of tumour PD-L1 expression and number of tumour infiltrating lymphocytes (TILs) is still largely unknown. Here, we investigated the impact on survival for CD3, CD8, FOXP3 and PD-L1 TIL counts and tumour PD-L1 expression in melanoma loco-regional metastases. In a patient series of loco-regional metastases from nodular melanomas (n = 78; n = 26 skin metastases, n = 52 lymph node metastases), expression of PD-L1 in tumour cells and the number of CD3, CD8, FOXP3 and PD-L1 positive TILs were determined by immunohistochemistry on tissue microarray (TMA) slides. Due to limited tumour tissue in the paraffin blocks, 67 of the 78 cases were included for tissue microarrays. Low FOXP3 TIL count and negative tumour PD-L1 expression (cut off 1%) were both significantly associated with reduced survival in lymph node metastases. Low FOXP3 TIL count was significantly associated with low CD8, CD3 and PD-L1 TIL counts. Negative tumour PD-L1 expression was significantly associated with low CD8 and PD-L1 TIL count, large lymph node metastasis tumour size and presence of necrosis in lymph node metastases. Our findings demonstrate for the first time the negative prognostic value of low FOXP3 TIL count and confirm a negative prognostic value of negative tumour PD-L1 expression in melanoma lymph node metastases.

Immune Biomarkers on Tissue Microarray Cores Support the Presence of Adjacent Tertiary Lymphoid Structures in Soft Tissue Sarcoma

Immunotherapy has emerged as a new treatment modality in some soft tissue sarcomas, particularly for tumors associated with tertiary lymphoid structures (TLSs). These structures are functional lymphoid aggregates, and their presence is indicative of an active anticancer immune response in the tumor microenvironment. The assessment of TLS as a predictive biomarker at scale on patient specimens remains challenging. Although tissue microarrays (TMAs) could facilitate this assessment, it is unclear whether small microarray cores can represent and identify associated TLS responses. We sought to use multiplex immunohistochemistry to identify key components of TLS: T cells, B cells, and dendritic cells. The multiplex panels (CD3, CD20, CD208, and PNAd) were applied to 80 cases both on TMAs and on their cognate available full-faced sections from epithelioid sarcoma and dedifferentiated/well-differentiated liposarcoma case series. TMAs were digitally scored for the number of immune cells using the HALO image analysis platform, and cognate full-faced sections were visually evaluated for the presence of TLS. An independent validation set of soft tissue sarcomas (N = 49) was stained with the CD3, CD20, and CD208, and scored by QuPath. A combined immune marker (defined as the presence of more than 24% CD3+ T cells, or 0.51% CD20+ B cells, or >0.14% CD208+ mature dendritic cells on tissue microarray cores) is highly specific (100%) and moderately sensitive (61%) to predict the existence of TLS on full-faced sections. The combined immune marker showed a sensitivity of 25% and specificity of 91% on the validation set. The combined immune marker assessed on tissue microarrays is highly specific in inferring the presence of TLS on cognate full-faced sections. Therefore, despite the small area sampled, tissue microarrays may be utilized to assess the clinical value of TLS on data sets where specificity is critical and large sample size can mitigate low-to-moderate sensitivity.

Loss of MTAP expression is strongly linked to homozygous 9p21 deletion, unfavorable tumor phenotype, and noninflamed microenvironment in urothelial bladder cancer

Homozygous 9p21 deletions usually result in a complete loss of S-methyl-5'-thioadenosine phosphorylase (MTAP) expression visualizable by immunohistochemistry (IHC). MTAP deficiency has been proposed as a marker for predicting targeted treatment response. A tissue microarray including 2,710 urothelial bladder carcinomas were analyzed for 9p21 deletion by fluorescence in situ hybridization and MTAP expression by IHC. Data were compared with data on tumor phenotype, patient survival, intratumoral lymphocyte subsets, and PD-L1 expression. The 9p21 deletion rate increased from pTaG2 low (9.2% homozygous, 25.8% heterozygous) to pTaG2 high (32.6%, 20.9%; p < 0.0001) but was slightly lower in pTaG3 (16.7%, 16.7%) tumors. In pT2-4 carcinomas, 23.3% homozygous and 17.9% heterozygous deletions were found, and deletions were tied to advanced pT (p = 0.0014) and poor overall survival (p = 0.0461). Complete MTAP loss was seen in 98.4% of homozygous deleted while only 1.6% of MTAP negative tumors had retained 9p21 copies (p < 0.0001). MTAP loss was linked to advanced stage and poor overall survival in pT2-4 carcinomas (p < 0.05 each). The relationship between 9p21 deletions/MTAP loss and poor patient prognosis was independent of pT and pN (p < 0.05 each). The 9p21 deletions were associated with a noninflamed microenvironment (p < 0.05). Complete MTAP loss is strongly tied to homozygous 9p21 deletion, aggressive disease, and noninflamed microenvironment. Drugs targeting MTAP-deficiency may be useful in urothelial bladder carcinoma. MTAP IHC is a near perfect surrogate for MTAP deficiency in this tumor type.

PLAP expression is linked to invasive tumor growth in urothelial carcinoma of the bladder

PURPOSE

Placental alkaline phosphatase (PLAP) is a protein with a poorly understood function that is normally only expressed in the placenta. In cancer, PLAP expression is a hallmark of germ cell neoplasms, but it can also occur in urothelial carcinoma. To evaluate the potential clinical significance of PLAP expression in bladder cancer, METHODS: PLAP protein was analyzed by immunohistochemistry in more than 2500 urothelial bladder carcinomas in a tissue microarray format.

RESULTS

PLAP staining was absent in normal urothelial cells but was observed in 15.9% of urothelial carcinomas, including 282 (11.5%) with weak, 57 (2.3%) with moderate, and 51 (2.1%) with strong staining. PLAP positivity occurred in 4.1% of 413 pTa G2 low-grade, 10.2% of 176 pTa G2 high-grade, and 7.2% of 97 pTa G3 tumors (p = 0.0636). As compared to pTa tumors, the PLAP positivity rate was markedly higher in 1341 pT2-4 carcinomas (19.8%, p < 0.0001). Within pT2-4 carcinomas, PLAP staining was unrelated to pT, pN, grade, L-status, V-status, overall survival, recurrence-free survival, and cancer-specific survival (p > 0.25). However, PLAP positivity was linked to p16 positivity (p = 0.0185), GATA3 positivity (p < 0.0001), and p63 expression loss (p = 0.0456).

CONCLUSION

In summary, these data show that PLAP is expressed in a significant fraction of pT2-4 urothelial carcinomas, unrelated to cancer aggressiveness but associated with specific molecular features. Once anti-PLAP cancer drugs become effective, urothelial carcinoma is a candidate tumor entity for clinical evaluation.

Prevalence and clinical significance of Claudin-3 expression in cancer: a tissue microarray study on 14,966 tumor samples

BACKGROUND

Claudin-3 (CLDN3) participates in the formation of the tight-junctions (TJs) that regulate intercellular permeability. Altered CLDN3 expression has been linked to tumor progression in multiple tumor types. Despite its widespread expression in normal epithelial cells, CLDN3 is considered an attractive drug target candidate, since it may be more accessible in cancer cells than in normal cells due to their less orchestrated cell growth.

METHODS

To comprehensively determine the prevalence of CLDN3 expression in cancer, a tissue microarray containing 14,966 samples from 133 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry.

RESULTS

CLDN3 immunostaining was observed in 8,479 (68.9%) of 12,314 analyzable tumors, including 11.6% with weak, 6.2% with moderate, and 51.1% with strong positivity. CLDN3 staining was found in 96 of 133 tumor categories, 80 of which contained at least one strongly positive case. CLDN3 positivity was most seen in neuroendocrine neoplasms (92-100%) and in adenocarcinomas (67-100%), tumors of the female genital tract, including various subtypes of ovarian and endometrial carcinoma (up to 100%), as well as different subtypes of breast cancer (95.3-100%). CLDN3 positivity was less common in squamous cell carcinomas (0-43.2%) and mainly absent in melanoma, mesenchymal, and hematolymphatic neoplasms. In clear cell renal cell carcinoma (ccRCC), low CLDN3 was strongly linked to poor ISUP (p < 0.0001), Fuhrman (p < 0.0001), and Thoenes (p < 0.0001) grades, advanced pT category (p < 0.0001), high UICC stage (p = 0.0006) and distant metastasis (p = 0.0011), as well as shortened overall (p = 0.0118) and recurrence-free (p < 0.0001) survival. In papillary RCC (pRCC), low CLDN3 was associated with poor grade (p < 0.05), high pT (p = 0.0273) and distant metastasis (p = 0.0357). In urothelial carcinoma high CLDN3 was linked to high grade (p < 0.0001) and nodal metastasis (p = 0.0111). The level of CLDN3 staining was unrelated to parameters of tumor aggressiveness in pancreatic, gastric, and breast cancer.

CONCLUSION

In conclusion, our data demonstrate significant levels of CLDN3 expression in many different tumor entities and identify reduced CLDN3 expression as a potential prognostic marker in RCC.

Carcinoembryonic Antigen Expression in Human Tumors: A Tissue Microarray Study on 13,725 Tumors

BACKGROUND/OBJECTIVES

Carcinoembryonic antigen (CEA) is a cell-surface glycoprotein serving as a drug target, diagnostic marker, and serum marker for cancer monitoring. However, prevalence data on CEA expression in cancer tissues vary considerably. This study was designed to determine CEA expression in normal and neoplastic tissues.

METHODS

A tissue microarray containing 13,725 samples from 120 different tumor types, as well as 76 different normal tissue types, was analyzed by immunohistochemistry (IHC).

RESULTS

CEA was detectable in 65 (54.2%) of 120 tumor categories, including 49 (40.8%) tumor types with at least one strongly positive case. CEA positivity was most common in colorectal adenomas (100%) and carcinomas (98.7%), other gastrointestinal adenocarcinomas (61.1-80.3%), medullary carcinomas of the thyroid (96.3%), pulmonary adenocarcinoma (73.7%), mucinous carcinomas of the ovary (79.8%) and the breast (43.2%), small-cell carcinomas of the lung (64.3%), and urinary bladder (38.9%). CEA overexpression was linked to high tumor grade and invasive growth (p < 0.0001 each) in urinary bladder cancer, and estrogen and HER2 receptor positivity (p ≤ 0.0158) in invasive breast cancer of no special type. In colorectal adenocarcinomas, reduced CEA expression was associated with mismatch repair deficiency (p < 0.0001).

CONCLUSIONS

The comprehensive list of CEA-positive human tumor types demonstrates that CEA is expressed in a broad range of epithelial neoplasms, many of which might benefit from CEA serum monitoring and anti-CEA therapies.

Steroidogenic Acute Regulatory Protein Is a Useful Marker for Sex-Cord-Stroma Tumors and Normal and Neoplastic Adrenocortical Tissue

CONTEXT.—

Steroidogenic acute regulatory (StAR) protein is a mitochondrial transport protein with a critical regulatory role for steroid hormone production. The tissue distribution of StAR expression is limited to few human normal tissues.

OBJECTIVE.—

To assess the diagnostic and prognostic value of StAR immunohistochemistry analysis.

DESIGN.—

A tissue microarray containing 19 202 samples from 152 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry.

RESULT.—

StAR immunostaining occurred in 198 (1.2%) of the 17 135 analyzable tumors. StAR expression was observed in 27 of 152 tumor categories, 9 of which included at least 1 strongly positive case. The highest rate of StAR positivity occurred in Leydig cell tumors of the testis and the ovary (100%), steroid cell tumors of the ovary (100%), adrenocortical carcinomas (93%) and adenomas (87%), Sertoli-Leydig cell tumors (67%) and granulosa cell tumors of the ovary (56%), as well as seminomas (7%). Nineteen other tumor entities showed-a usually weak-StAR positivity in less than 6% of cases. A comparison with preexisting Melan-A (a melanocyte antigen) data revealed that StAR was more often positive in adrenocortical neoplasms and in Leydig cell tumors while StAR (but not Melan-A) was negative in Sertoli cell tumors.

CONCLUSIONS.—

Our data provide a comprehensive overview on the patterns of StAR immunostaining in human tumors and suggest a diagnostic utility of StAR immunohistochemistry for supporting a diagnosis of Leydig cell tumors or of normal or neoplastic adrenocortical tissue.

PAX6 is a useful marker for pancreatic origin of neuroendocrine neoplasms: A tissue microarray study evaluating more than 19,000 tumors from 150 different tumor types

PAX6 immunohistochemistry (IHC) was proposed as a tool to identify a pancreatic origin of neuroendocrine neoplasms (NENs). To evaluate the diagnostic utility of PAX6 IHC, a tissue microarray containing 19,214 samples from 150 tumor types was analyzed. Data on progesterone receptor (PR) and glutamate decarboxylase 2 (GAD2) expression were available from previous studies. PAX6 staining occurred in 2.6% of 17,224 analyzable tumors and 60 tumor categories showed PAX6 positivity in at least one case. The highest rates of PAX6 positivity occurred in pancreatic (42.9-70.8%) and other NENs (up to 50.0%), testicular tumors (up to 58.3%), basal cell carcinomas of the skin (51.9%), squamous cell carcinomas of different organs (1.5-11.8%), and in gynecological tumors (up to 30%). For detection of pancreatic origin of NENs, sensitivity was highest for PAX6 (68.7%) followed by GAD2 (62.6%) and PR (52.5%) while specificity was highest for GAD2 (95.2%), followed by PR (91.3%), and PAX6 (91.1%). Of the analyzed combinations, the highest sensitivity (53.8%) and specificity (100%) was found for PAX6/GAD2, although combinations of PAX6/PR (49.5%/99.3%), PR/GAD2 (40.7%/98.9%), and PAX6/PR/GAD2 (40.6%/100%) did also result in high specificity. Only 14% of the 118 NENs with negativity for all three antibodies were of pancreatic origin. It is concluded that PAX6 IHC is useful to identify a pancreatic origin in case of NEN metastases of unknown origin. The combination with GAD2 and PR further increase the diagnostic performance of PAX6 and results in a >98% specificity in case of positivity for at least 2 of these markers.

PGP9.5 expression in human tumors: A tissue microarray study on 13,920 tumors from 120 different tumor entities

The protein gene product 9.5 (PGP9.5), also termed ubiquitin C-terminal hydrolase L1 (UCH-L1) is an important component of the ubiquitination/deubiquitination system and plays a role in axonal transport. To comprehensively determine PGP9.5 expression in neoplastic tissues, a tissue microarray containing 13,920 samples from 120 different tumor types and subtypes was analyzed by immunohistochemistry (IHC). PGP9.5 immunostaining was found in 109 of 120 tumor categories, 87 of which contained at least one strongly positive case. PGP9.5 positivity was most seen in neuronal and neuroendocrine neoplasms (50-100 %), germ cell neoplasms (28-84 %), sarcomas and carcinosarcomas (up to 91 %), and in mesotheliomas (58-83 %). In clear cell RCC (renal cell carcinomas), strong PGP9.5 staining was associated with high ISUP (International Society of Urological Pathology) grade (p<0.0001), advanced pT stage (p=0.0003), nodal (p=0.0242) and distant metastasis (p<0.0001) as well as with a short overall, tumor specific and recurrence free survival (p≤0.0007 each). In papillary RCC, strong PGP9.5 staining was associated with high ISUP grade (p=0.009) and reduced recurrence free survival (p=0.0221). In urothelial carcinoma of the urinary bladder, high PGP9.5 expression was associated with muscle-invasion (p<0.0001). PGP9.5 immunostaining was unrelated to histological parameters for tumor aggressiveness in 295 serous high-grade ovarian carcinomas, 174 endometrioid endometrium carcinomas, 292 papillary and 89 follicular thyroid carcinomas, 405 ductal adenocarcinomas of the pancreas and in 327 gastric adenocarcinomas. In summary, our data provide a comprehensive overview of PGP9.5 expression in cancer and demonstrate positive cases in a broad range of entities. PGP9.5 overexpression is linked to patient outcome in some tumor entities (i.e., clear cell RCC) but appears to be unrelated to clinically relevant tumor characteristics in many other frequent tumor entities.

Reduced p63 expression is linked to unfavourable prognosis in muscle-invasive urothelial carcinoma of the bladder

Objective

There is a shortage of established prognostic biomarkers in bladder cancer. One candidate is tumour protein 63 (p63), a transcription factor of the p53 gene family that is expressed in the normal urothelium. Recently proposed RNA expression-based molecular classifiers of bladder cancer identified high p63 expression as a component of a basal/squamous subtype linked to poor patient prognosis.

Methods

In this study, p63 protein expression was analysed by immunohistochemistry on more than 2500 urothelial bladder carcinomas in a tissue microarray format to determine its relationship with clinicopathological parameters of disease progression and patient outcome.

Results

Nuclear p63 staining was seen in all cells of normal urothelium and at elevated levels in pTaG2 tumours. The rate of p63 positive cases and the staining intensity was lower in pTaG3 tumours (93.2%, p < 0.0001 for pTaG3 vs. pTaG2) and markedly lower in pT2-4 carcinomas (83.5%, p = 0.0120 for pT2-4 vs. pTaG3). Within 1018 pT2-4 carcinomas treated by cystectomy, low p63 expression was linked to nodal metastasis (p = 0.0028) and overall survival (p = 0.0005). The association with survival was independent of pT and pN (p = 0.0081). p63 expression was associated with GATA3 expression (p < 0.0001), a luminal cell type marker associated with favourable disease. A joint analysis of p63 and GATA3 did not suggest that GATA3 could provide additional prognostic information.

Conclusion

The independent prognostic role of reduced p63 expression in advanced urothelial carcinomas suggests that p63 could be a useful biomarker to distinguish pT2-4 urothelial carcinomas.

IL-6/STAT3 signaling pathway induces prostate apoptosis response protein-4(PAR-4) to stimulate malignant behaviors of hepatocellular carcinoma cells

INTRODUCTION AND OBJECTIVES

Prostate apoptosis response protein-4 (PAR-4) is considered a tumor suppressor. However, the role of PAR-4 in hepatocellular carcinoma (HCC) has rarely been reported. The study explores the role of PAR-4 in the malignant behaviors of HCC cells.

MATERIALS AND METHODS

TCGA database was applied to analyze the expression of PAR-4 in HCC. Evaluated PAR-4 relationship with clinical parameters and prognosis by tissue microarray; expression of STAT3, p-STAT3, Src and Ras was detected by Western blotting or laser confocal microscopy. Cell scratch and flow cytometry assays were used to observe IL-6 regulation of the malignant behaviors of HCC cells. The tumorigenic potential of HCC cells in vivo was evaluated in a nude mouse tumor model.

RESULTS

Analysis indicated that the expression of PAR-4 in HCC tissues was significantly higher than that in normal liver tissues; and PAR-4 interacted with STAT3. KEGG analysis showed that PAR-4 plays a role in the Janus kinase (JAK)/STAT signaling pathway. The positive expression rate of PAR-4 in HCC tissues was significantly higher than that in adjacent tissues. Positive correlation between IL-6 and PAR-4 expression in the HCC tissues. Exogenous IL-6 significantly promoted the proliferation and migration of HCC cells and up-regulated the expression of PAR-4 and p-STAT3 in HCC cells. Interference of the expression of PAR-4 could reduce the malignant behaviors of HCC cells and inhibit tumorigenesis in a nude mouse tumor model.

CONCLUSIONS

PAR-4 expression is positively correlated with HCC; PAR-4 promotes malignant behavior of HCC cells mediated by the IL-6/STAT3 signaling pathway.

The differences between pure and mixed invasive micropapillary breast cancer: the epithelial-mesenchymal transition molecules and prognosis

PURPOSE

Invasive micropapillary carcinoma (IMPC) of the breast is known for its high metastatic potential, but the definition of pure and mixed IMPC remains unclear. This retrospective cohort study aims to investigate the prognostic significance of the micropapillary component ratio and the expression of critical molecules of epithelial-mesenchymal transition (EMT), including E-cadherin (E-cad), N-cadherin (N-cad), CD44s, and β-catenin (β-cat), in distinguishing between pure and mixed IMPCs.

METHODS

We analyzed 100 cases of locally advanced IMPC between 2000 and 2018 and excluded patients who received neoadjuvant chemotherapy. Pure IMPC was defined as having a micropapillary component of over 90%. A comprehensive recording of prognostic parameters was conducted. The IMPC areas were analyzed using the immunohistochemical (IHC) staining method on the microarray set for pure and mixed IMPC patients. Pearson's chi-square, Fisher's exact tests, Kaplan-Meier analysis, and Cox proportional hazards analysis were employed.

RESULTS

The comparative survival analysis of the entire group, based on overall survival (OS) and disease-free survival (DFS), revealed no significant difference between the pure and mixed groups (P = 0.480, HR = 1.474 [0.502-4.325] and P = 0.390, HR = 1.587 [0.550-4.640], respectively). However, in the pure IMPC group, certain factors were found to be associated with a higher risk of short survival. These factors included skin involvement (P = 0.050), pT3&4 category (P = 0.006), a ratio of intraductal component (> 5%) (P = 0.032), and high-level expression of N-cad (P = 0.020). Notably, none of the risk factors identified for short OS in pure IMPC cases were observed as significant risks in mixed cases and vice versa. Furthermore, N-cad was identified as a poor prognostic marker for OS in pure IMPCs (P = 0.002).

CONCLUSION

The selection of a 90% ratio for classifying pure IMPCs revealed significant differences in certain molecular and prognostic parameters between pure and mixed groups. Notably, the involvement of N-cadherin in the epithelial-mesenchymal transition (EMT) process provided crucial insights for predicting OS and DFS while also distinguishing between the two groups. These findings strongly support the notion that the pure IMPC subgroup represents a distinct entity characterized by unique molecular characteristics and behavioral patterns.

TTF-1 is a highly sensitive but not fully specific marker for pulmonary and thyroidal cancer: a tissue microarray study evaluating more than 17,000 tumors from 152 different tumor entities

Thyroid transcription factor 1 (TTF-1) immunohistochemistry (IHC) is routinely used for the distinction of primary pulmonary adenocarcinomas. However, TTF-1 can also occur in other malignancies. A tissue microarray containing 17,772 samples from 152 different tumor types was analyzed. Napsin-A, CK20, SATB2, FABP1, and Villin-1 IHC data were available from previous studies. TTF-1 staining was seen in 82 of 152 tumor categories including thyroidal cancers (19-100%), adenocarcinomas (94%), neuroendocrine tumors (67%) of the lung, small cell neuroendocrine carcinomas (71-80%), mesenchymal tumors (up to 42%), and thymomas (39%). Comparative analysis of TTF-1 and Napsin-A revealed a sensitivity/specificity of 94%/86% (TTF-1), 87%/98% (Napsin-A), and 85%/99.1% (TTF-1 and Napsin-A) for the distinction of pulmonary adenocarcinomas. Combined analysis of TTF-1 and enteric markers revealed a positivity for TTF-1 and at least one enteric marker in 22% of pulmonary adenocarcinomas but also a TTF-1 positivity in 6% of colorectal, 2% of pancreatic, and 3% of gastric adenocarcinomas. TTF-1 is a marker of high sensitivity but insufficient specificity for pulmonary adenocarcinomas. A small fraction of TTF-1-positive gastrointestinal adenocarcinomas represents a pitfall mimicking enteric-type pulmonary adenocarcinoma. Combined analysis of TTF-1 and Napsin-A improves the specificity of pulmonary adenocarcinoma diagnosis.

Prevalence and Significance of AGR2 Expression in Human Cancer

BACKROUND

Anterior gradient 2 (AGR2) is a resident endoplasmic reticulum (ER) protein with a vital role in embryonal development, mucus maturation, tissue regeneration, and wound healing.

METHODS

To determine the prevalence and clinical significance of AGR2 expression in cancer, a tissue microarray containing 14,966 tumors from 134 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry (IHC).

RESULTS

AGR2 positivity was found in 103 of 134 tumor categories, and 83 tumor categories contained at least one strongly positive case. AGR2 expression was most frequently seen in tumors of the female genital tract, particularly adenocarcinomas (up to 100%), various breast cancer subtypes (57.1%-100%), urothelial carcinoma (74.6%-100%), adenocarcinomas of the upper and lower gastrointestinal tract (93.6%-99.6%), and pancreaticobiliary cancers (65.2%-98.2%). AGR2 positivity was slightly less common in squamous cell carcinomas (46.4%-77.3%) and mainly absent in mesenchymal and lymphoid tumors. While AGR2 expression was only weak or absent in the normal thyroid, it was moderate to strong in 46.0% of adenomas, 52.8% of follicular carcinomas, and 81.8% of papillary carcinomas of the thyroid. High AGR2 expression was strongly linked to poor ISUP (p < 0.0001), Fuhrman (p < 0.0001), and Thoenes (p < 0.0001) grades as well as advanced pT stage (p = 0.0035) in clear cell renal cell carcinoma (ccRCC). Low AGR2 expression was associated with high BRE grade in breast cancer (p = 0.0049), nodal metastasis (p = 0.0275) and RAS mutation (p = 0.0136) in colorectal cancer, nodal metastasis (p = 0.0482) in endometrioid endometrial carcinoma, high grade in noninvasive urothelial carcinoma (p = 0.0003), and invasive tumor growth in urothelial carcinoma (p < 0.0001).

CONCLUSIONS

It is concluded that AGR2 expression occurs in a broad range of different tumor entities and that AGR2 assessment may serve as a diagnostic aid for the distinction of thyroidal neoplasms and as a prognostic marker in various cancer types.

Expression patterns of HDAC6 in correlation to ARID1A status in different subtypes of endometriosis: A retrospective tissue microarray analysis

Endometriosis is a disease affecting approximately 10% of reproductive age women. Loss of the tumor suppressor gene AT-rich interactive domain-containing protein 1A (ARID1A) occurs in some endometriosis cases. Histone deacetylase 6 (HDAC-6) is an enzyme with implication in several diseases including different cancer types and immunological disorders, where it is involved in protein trafficking and degradation, cell shape, and migration. In ARID1A-deficient ovarian cancer increased HDAC-6 expression lead to apoptosis-inhibiting post-translational modification of p53. It is not known if HDAC-6 expression is also altered in ARID1A-deficient endometriosis. The aim of this study was to assess HDAC-6 expression in endometriotic lesions in correlation to ARID1A-status. Two tissue-microarrays with 168 endometriotic lesions, including ovarian (64/168, 38 %), peritoneal (66/168, 39 %) and deep-infiltrating (38/168, 23 %) subtypes, and 73 endometrium of women without endometriosis were assessed. Mean ARID1A immunoreactivity score (IRS) in endometriosis group was 10.83 (±2.36) and 10.78 (±1.94) in the epithelium and stroma, respectively, while the respective mean HDAC6 IRS were 9.16 (±2.76) and 5.94 (±2.88). The comparison of the HDAC6 expression between endometriosis subtypes showed higher expression in deep-infiltrating endometriosis, in both, epithelium (p = 0.032) and stroma (p = 0.007). In ARID1A negative cases, epithelial expression of HDAC6 was higher in endometriosis compared to women without endometriosis (p = 0.031), and this was also specifically observed in the subset of ovarian endometriosis (p = 0.037). There were no significant differences in the stromal expression of HDAC6. In conclusion, our results demonstrate a complex expression pattern of HDAC6 depending on ARID1A status in different endometriosis subtypes. Further studies on HDAC6 and ARID1A are important to elucidate mechanisms involved in malignant transformation of endometriosis.

Evaluation of SOX-10 immunohistochemical expression in canine melanoma and non-melanocytic tumors by tissue microarray

Melanoma is the most common malignant oral tumor in dogs. It frequently presents a diagnostic challenge as many melanomas lack or contain scant melanin and may have a variable microscopic phenotype. Previous studies evaluating immunohistochemical markers for diagnosing melanoma have shown limited sensitivity and/or specificity for S-100, PNL2, melan A, TRP-1, TRP-2, and HMB-45. Sry-related HMG-box gene 10 (SOX-10) is a transcription factor associated with melanocytic, peripheral neural crest, and peripheral nervous system development. In humans, SOX-10 expression has been demonstrated in melanoma, breast carcinoma, glioma, and schwannoma, but has only recently been explored in veterinary species. In this study, 198 tumors comprised of 147 melanocytic neoplasms and 51 non-melanocytic neoplasms were evaluated by immunohistochemistry using a tissue microarray for SOX-10, PNL2, melan A, TRP-1, and TRP-2 expressions. The SOX-10 had the highest diagnostic sensitivity (96.7%) in melanomas. In addition, SOX-10 had the highest percentage (91.5%; 130/142) of melanomas label at least 75% of neoplastic cells. Of the 51 selected non-melanocytic tumors examined, SOX-10 labeling was observed in mammary carcinomas (6/6), gliomas (4/4), and oral soft tissue sarcomas (4/18). Of the 41 non-melanocytic oral neoplasms evaluated, SOX-10 had a specificity of 92.7%. Therefore, SOX-10 represents a useful immunohistochemical screening marker for the diagnosis of canine melanoma given its extremely high sensitivity and robust labeling intensity. The SOX-10 may have utility in diagnosing some non-melanocytic neoplasms in the dog, although this requires further investigation.

Loss of vimentin expression in preoperative biopsies independently predicts poor prognosis, lymph node metastasis and recurrence in endometrial cancer

BACKGROUND

Precise preoperative risk classification of endometrial cancer is crucial for treatment decisions. Existing clinical markers often fail to accurately predict lymph node metastasis and recurrence risk. Loss of vimentin expression has emerged as a potential marker for predicting recurrence in low-risk endometrial cancer patients. We assessed whether vimentin expression in preoperative biopsies predicts poor prognosis and lymph node metastasis in a large multicentre cohort.

METHODS

Vimentin expression was evaluated using immunohistochemistry in 1483 patients diagnosed with endometrial cancer across 14 hospitals in Europe. Expression levels of vimentin were analyzed in conjunction with clinical characteristics for predicting disease-specific survival and lymph node metastases.

RESULTS

Vimentin loss was significantly associated with aggressive disease and poor survival. Adjusted for clinicopathological variables, vimentin remained independently prognostic with a hazard ratio (HR) of 1.68 (95% CI 1.16-2.42, P = 0.006). Vimentin expression remained independently prognostic in endometrioid endometrial cancer- and FIGO staged 1 patient. Interestingly, vimentin loss independently predicted lymph node metastases, with an HR of 1.83 (95% CI 1.13-2.95, P = 0.014).

CONCLUSIONS

Loss of vimentin in preoperative biopsies serves as an independent predictor of poor prognosis and lymph node metastases. Incorporating vimentin as a clinical marker can improve risk stratification and treatment decisions.

Prevalence of S-methyl-5'-thioadenosine Phosphorylase (MTAP) Deficiency in Human Cancer: A Tissue Microarray Study on 13,067 Tumors From 149 Different Tumor Types

Loss of S-methyl-5'-thioadenosine phosphorylase (MTAP) expression is a common event in cancer leading to a critical vulnerability of cancer cells towards anti-cancer drugs. Homozygous MTAP deletions result in a complete expression loss that can be detected by immunohistochemistry (IHC). In this study, a tissue microarray containing 17,078 samples from 149 different tumor entities was analyzed by IHC, and complete MTAP loss was validated by fluorescence in situ hybridization. MTAP loss was observed in 83 of 149 tumor categories, including neuroendocrine neoplasms (up to 80%), Hodgkin lymphoma (50.0%), mesothelioma (32.0% to 36.8%), gastro-intestinal adenocarcinoma (4.0% to 40.5%), urothelial neoplasms (10.5% to 36.7%), squamous cell carcinomas (up to 38%), and various types of sarcomas (up to 20%) and non-Hodgkin lymphomas (up to 14%). Homozygous MTAP deletion was found in 90% to 100% of cases with MTAP expression loss in most tumor categories. However, neuroendocrine tumors, Hodgkin lymphomas, and other lymphomas lacked MTAP deletions. MTAP deficiency was significantly linked to unfavorable tumor phenotype in selected tumor entities and the presence of PD-L1 expression on tumor cells, absence of PD-L1 expression on immune cells, and a low density of CD8 + lymphocytes. In summary, MTAP deficiency can occur in various tumor entities and is linked to unfavorable tumor phenotype and noninflamed tumor microenvironment, but is not always related to deletions. MTAP IHC is of considerable diagnostic value for the detection of neoplastic transformation in multiple different applications.

Expression of Trefoil Factor 1 (TFF1) in Cancer: A Tissue Microarray Study Involving 18,878 Tumors

Background/Objectives: Trefoil factor 1 (TFF1) plays a role in the mucus barrier. Methods: To evaluate the prevalence of TFF1 expression in cancer, a tissue microarray containing 18,878 samples from 149 tumor types and 608 samples of 76 normal tissue types was analyzed through immunohistochemistry (IHC). Results: TFF1 staining was detectable in 65 of 149 tumor categories. The highest rates of TFF1 positivity were found in mucinous ovarian carcinomas (76.2%), colorectal adenomas and adenocarcinomas (47.1-75%), breast neoplasms (up to 72.9%), bilio-pancreatic adenocarcinomas (42.1-62.5%), gastro-esophageal adenocarcinomas (40.4-50.0%), neuroendocrine neoplasms (up to 45.5%), cervical adenocarcinomas (39.1%), and urothelial neoplasms (up to 24.3%). High TFF1 expression was related to a low grade of malignancy in non-invasive urothelial carcinomas of the bladder (p = 0.0225), low grade of malignancy (p = 0.0003), estrogen and progesterone receptor expression (p < 0.0001), non-triple negativity (p = 0.0005) in invasive breast cancer of no special type, and right-sided tumor location (p = 0.0021) in colorectal adenocarcinomas. Conclusions: TFF1 IHC has only limited utility for the discrimination of different tumor entities given its expression in many tumor entities. The link between TFF1 expression and parameters of malignancy argues for a relevant biological role of TFF1 in cancer. TFF1 may represent a suitable therapeutic target due to its expression in only a few normal cell types.

17p13 (TP53) Deletions Are Associated With an Aggressive Phenotype but Unrelated to Patient Prognosis in Urothelial Bladder Carcinomas

17p13 deletions including TP53 and other genes represent a common cause for reduced/lost p53 function in tumor cells. In this study, we analyzed the impact of 17p13 (TP53) deletions and p53 expression on tumor aggressiveness and patient prognosis in urothelial carcinoma. The 17p13 copy number status was analyzed by fluorescence in situ hybridization (FISH) on more than 2700 urothelial bladder carcinomas in a tissue microarray format. 17p13 deletion data were compared to p53 expression data measured by immunohistochemistry (IHC) in a previous study. Different types of p53 alterations were compared with tumor phenotype and clinical outcome data. Deletions of 17p13 occurred in 23% of 2185 analyzable carcinomas. The fraction of tumors with 17p13 deletions increased from pTa G2 low (9%) to pTa G3 (24%, p < 0.0001). In muscle-invasive carcinomas, 17p13 deletions were associated with advanced pT stage (p = 0.0246), but unrelated to patient prognosis (p > 0.5). 17p13 deletions were significantly related to p53 immunostaining (p = 0.0375). 17p13 deletions were most common in tumors with complete lack of p53 staining (31%), which supports the concept that many of these tumors have a complete loss of p53 function (p53 null phenotype). 17p13 deletions were also increased in tumors with high p53 staining (25%). In conclusion, 17p13 deletions were most commonly seen in p53 negative cancers, supporting their role as a cause for the p53 null phenotype in urothelial cancer. The association of 17p13 deletions with high grade and advanced pT stage may reflect increasing genomic instability going along with stage and grade progression.

PAX8 expression in cancerous and non-neoplastic tissue: a tissue microarray study on more than 17,000 tumors from 149 different tumor entities

PAX8 plays a role in development of the thyroid, kidney, and the Wolffian and Mullerian tract. In surgical pathology, PAX8 immunohistochemistry is used to determine tumors of renal and ovarian origin, but data on its expression in other tumors are conflicting. To evaluate PAX8 expression in normal and tumor tissues, a tissue microarray containing 17,386 samples from 149 different tumor types and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. PAX8 results were compared with previously collected data on cadherin 16 (CDH16). PAX8 positivity was found in 40 different tumor types. The highest rate of PAX8 positivity was found in thyroidal neoplasms of follicular origin (98.6-100%), gynecological carcinomas (up to 100%), renal tumors (82.6-97.8%), and urothelial neoplasms (2.3-23.7%). Important tumors with near complete absence of PAX8 staining (< 1%) included all subtypes of breast cancers, hepatocellular carcinomas, gastric, prostatic, pancreatic, and pulmonary adenocarcinomas, neuroendocrine neoplasms, small cell carcinomas of various sites, and lymphomas. High PAX8 expression was associated with low tumor grade in 365 non-invasive papillary urothelial carcinomas (p < 0.0001) but unrelated to patient outcome and/or tumor phenotype in clear cell renal cell carcinoma, high-grade serous ovarian cancer, and endometrioid endometrial carcinoma. For determining a renal tumor origin, sensitivity was 88.1% and specificity 87.2% for PAX8, while sensitivity was 85.3% and specificity 95.7% for CDH16. The combination of PAX8 and CDH16 increased specificity to 96.8%. In conclusion, PAX8 immunohistochemistry is a suitable diagnostic tool. The combination of PAX8 and CDH16 positivity has high specificity for renal cell carcinoma.

CD163+ macrophages in mantle cell lymphoma induce activation of prosurvival pathways and immune suppression

ABSTRACT

Mantle cell lymphoma (MCL) is dependent on a supportive tumor immune microenvironment (TIME) in which infiltration of CD163+ macrophages has a negative prognostic impact. This study explores how abundance and spatial localization of CD163+ cells are associated with the biology of MCL, using spatial multiomic investigations of tumor and infiltrating CD163+ and CD3+ cells. A total of 63 proteins were measured using GeoMx digital spatial profiling in tissue microarrays from 100 diagnostic MCL tissues. Regions of interest were selected in tumor-rich and tumor-sparse tissue regions. Molecular profiling of CD163+ macrophages, CD20+ MCL cells, and CD3+ T-cells was performed. To validate protein profiles, 1811 messenger RNAs were measured in CD20+ cells and 2 subsets of T cells. Image analysis was used to extract the phenotype and position of each targeted cell, thereby allowing the exploration of cell frequencies and cellular neighborhoods. Proteomic investigations revealed that CD163+ cells modulate their immune profile depending on their localization and that the immune inhibitory molecules, V-domain immunoglobulin suppressor of T-cell activation and B7 homolog 3, have higher expression in tumor-sparse than in tumor-rich tissue regions and that targeting should be explored. We showed that MCL tissues with more abundant infiltration of CD163+ cells have a higher proteomic and transcriptional expression of key components of the MAPK pathway. Thus, the MAPK pathway may be a feasible therapeutic target in patients with MCL with CD163+ cell infiltration. We further showed the independent and combined prognostic values of CD11c and CD163 beyond established risk factors.

Loss of ATRX and DAXX in pancreatic neuroendocrine tumors: Association with recurrence risk, cellular phenotype, and heterogeneity

Pancreatic neuroendocrine tumors (PanNETs) comprise a heterogeneous group of neoplasms in terms of biological behavior. This study aims to develop a practical algorithm based on emerging biomarkers, including chromatin-remodeling molecules DAXX/ATRX/H3K36me3, in conjunction with established prognostic factors, such as WHO grade and size. In immunohistochemical analyses, 18 of the 111 (16.2%) primary PanNETs showed DAXX or ATRX loss in a mutually exclusive manner. DAXX/ATRX loss was significantly correlated with higher recurrence risk and better predicted postoperative recurrence than WHO grade. We proposed a novel algorithm for stratifying patients with resectable PanNET into three groups according to recurrence risk: (A) WHO Grade 1 and ≤2 cm (very low-risk); for the others, (B) retained DAXX/ATRX (low-risk) and (C) DAXX/ATRX complete/heterogeneous loss (high-risk). Furthermore, we elucidated the intratumoral heterogeneities of PanNETs. Among cases with DAXX or ATRX loss, nine cases demonstrated heterogeneous loss of expression of DAXX/ATRX/H3K36me3. The majority of cases with DAXX/ATRX loss, either homogeneous or heterogeneous loss, showed uniform α-cell-like phenotype (ARX1+/PDX1-). In cases of metastatic or recurrent tumors, the expression pattern was identical to that observed in at least part of the primary tumor. In some instances, the expression pattern differed among different metastatic or recurrent tumors of the same patient. In summary, we propose a clinically useful and practical algorithm for postoperative recurrence risk stratification in PanNETs, by combining DAXX/ATRX status with WHO grade and size. Moreover, our findings highlighted the frequent spatiotemporal heterogeneity of chromatin-remodeling molecule expression in PanNETs with an α-cell phenotype, offering insights into tumorigenesis.

Deep Learning Glioma Grading with the Tumor Microenvironment Analysis Protocol for Comprehensive Learning, Discovering, and Quantifying Microenvironmental Features

Gliomas are primary brain tumors that arise from neural stem cells, or glial precursors. Diagnosis of glioma is based on histological evaluation of pathological cell features and molecular markers. Gliomas are infiltrated by myeloid cells that accumulate preferentially in malignant tumors, and their abundance inversely correlates with survival, which is of interest for cancer immunotherapies. To avoid time-consuming and laborious manual examination of images, a deep learning approach for automatic multiclass classification of tumor grades was proposed. As an alternative way of investigating characteristics of brain tumor grades, we implemented a protocol for learning, discovering, and quantifying tumor microenvironment elements on our glioma dataset. Using only single-stained biopsies we derived characteristic differentiating tumor microenvironment phenotypic neighborhoods. The study was complicated by the small size of the available human leukocyte antigen stained on glioma tissue microarray dataset - 206 images of 5 classes - as well as imbalanced data distribution. This challenge was addressed by image augmentation for underrepresented classes. In practice, we considered two scenarios, a whole slide supervised learning classification, and an unsupervised cell-to-cell analysis looking for patterns of the microenvironment. In the supervised learning investigation, we evaluated 6 distinct model architectures. Experiments revealed that a DenseNet121 architecture surpasses the baseline's accuracy by a significant margin of 9% for the test set, achieving a score of 69%, increasing accuracy in discerning challenging WHO grade 2 and 3 cases. All experiments have been carried out in a cross-validation manner. The tumor microenvironment analysis suggested an important role for myeloid cells and their accumulation in the context of characterizing glioma grades. Those promising approaches can be used as an additional diagnostic tool to improve assessment during intraoperative examination or subtyping tissues for treatment selection, potentially easing the workflow of pathologists and oncologists.

A study predicting long-term survival capacity in postoperative advanced gastric cancer patients based on MAOA and subcutaneous muscle fat characteristics

BACKGROUND

The prognosis of advanced gastric cancer (AGC) is relatively poor, and long-term survival depends on timely intervention. Currently, predicting survival rates remains a hot topic. The application of radiomics and immunohistochemistry-related techniques in cancer research is increasingly widespread. However, their integration for predicting long-term survival in AGC patients has not been fully explored.

METHODS

We Collected 150 patients diagnosed with AGC at the Affiliated Zhongshan Hospital of Dalian University who underwent radical surgery between 2015 and 2019. Following strict inclusion and exclusion criteria, 90 patients were included in the analysis. We Collected postoperative pathological specimens from enrolled patients, analyzed the expression levels of MAOA using immunohistochemical techniques, and quantified these levels as the MAOAHScore. Obtained plain abdominal CT images from patients, delineated the region of interest at the L3 vertebral body level, and extracted radiomics features. Lasso Cox regression was used to select significant features to establish a radionics risk score, convert it into a categorical variable named risk, and use Cox regression to identify independent predictive factors for constructing a clinical prediction model. ROC, DCA, and calibration curves validated the model's performance.

RESULTS

The enrolled patients had an average age of 65.71 years, including 70 males and 20 females. Multivariate Cox regression analysis revealed that risk (P = 0.001, HR = 3.303), MAOAHScore (P = 0.043, HR = 2.055), and TNM stage (P = 0.047, HR = 2.273) emerged as independent prognostic risk factors for 3-year overall survival (OS) and The Similar results were found in the analysis of 3-year disease-specific survival (DSS). The nomogram developed could predict 3-year OS and DSS rates, with areas under the ROC curve (AUCs) of 0.81 and 0.797, respectively. Joint calibration and decision curve analyses (DCA) confirmed the nomogram's good predictive performance and clinical utility.

CONCLUSION

Integrating immunohistochemistry and muscle fat features provides a more accurate prediction of long-term survival in gastric cancer patients. This study offers new perspectives and methods for a deeper understanding of survival prediction in AGC.

KLK7 expression in human tumors: a tissue microarray study on 13,447 tumors

BACKGROUND

Kallikrein-related peptidase 7 (KLK7) is a chymotrypsin-like serine protease which is essential for the desquamation of corneocytes and thus plays a pivotal role in maintaining skin homeostasis. In cancer, KLK7 overexpression was suggested to represent a route for metastasis through cleavage of cell junction and extracellular matrix proteins of cancer cells.

METHODS

To comprehensively determine KLK7 protein expression in normal and neoplastic tissues, a tissue microarray containing 13,447 samples from 147 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry.

RESULTS

KLK7 positivity was found in 64 of 147 tumor categories, including 17 tumor categories with at least one strongly positive case. The highest rate of KLK7 positivity was found in squamous cell carcinomas from various sites of origin (positive in 18.1%-63.8%), ovarian and endometrium cancers (4.8%-56.2%), salivary gland tumors (4.8%-13.7%), bilio-pancreatic adenocarcinomas (20.0%-40.4%), and adenocarcinomas of the upper gastrointestinal tract (3.3%-12.5%). KLK7 positivity was linked to nodal metastasis (p = 0.0005), blood vessel infiltration (p = 0.0037), and lymph vessel infiltration (p < 0.0001) in colorectal adenocarcinoma, nodal metastasis in hepatocellular carcinoma (p = 0.0382), advanced pathological tumor stage in papillary thyroid cancer (p = 0.0132), and low grade of malignancy in a cohort of 719 squamous cell carcinomas from 11 different sites of origin (p < 0.0001).

CONCLUSIONS

These data provide a comprehensive overview on KLK7 expression in normal and neoplastic human tissues. The prognostic relevance of KLK7 expression and the possible role of KLK7 as a drug target need to be further investigated.

Staining pattern of specific and cross-reacting Melan-A antibodies: A comparative study on 15,840 samples from 133 human tumor types

The Melan-A (melanocyte antigen) protein, also termed 'melanoma antigen recognized by T cells 1' (MART-1) is a protein with unknown function whose expression is specific for the melanocyte lineage. Antibodies against Melan-A are thus used for identifying melanocytic tumors, but some Melan-A antibodies show an additional - diagnostically useful - cross-reactivity against an unspecified protein involved in corticosteroid hormone synthesis. To comprehensively compare the staining patterns of a specific and a cross-reactive Melan-A antibody in normal and neoplastic tissues, tissue microarrays containing 15,840 samples from 133 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. For the Melan-A-specific antibody 'Melan-A specific' (MSVA-900M), Melan-A positivity was seen in 96.0% of 25 benign nevi, 93.0% of 40 primary and 86.7% of 75 metastatic melanomas, 82.4% of 85 renal angiomyolipomas as well as 96.4% of 84 neurofibromas, 2.2% of 46 granular cell tumors, 1.0% of 104 schwannomas, and 1.1% of 87 leiomyosarcomas. The cross-reactive antibody 'Melan-A+' (MSVA-901M+) stained 98.1% of the tumors stained by 'Melan-A specific'. In addition, high positivity rates were seen in sex-cord-stroma tumors of the ovary (35.3%-100%) and the testis (86.7%) as well as for adrenocortical neoplasms (76.3%-83.0%). Only nine further tumor groups showed Melan-A+ staining, including five different categories of urothelial carcinomas. Our data provide a comprehensive overview on the staining patterns of specific and cross-reactive Melan-A antibodies. The data demonstrate that both antibodies are highly useful for their specific purpose. It is important for pathologists to distinguish these two Melan-A antibody subtypes for their daily work.

Stimulator of Interferon Genes Protein (STING) Expression in Cancer Cells: A Tissue Microarray Study Evaluating More than 18,000 Tumors from 139 Different Tumor Entities

Stimulator of interferon genes protein (STING) activates the immune response in inflammatory cells. STING expression in cancer cells is less well characterized, but STING agonists are currently being evaluated as anticancer drugs. A tissue microarray containing 18,001 samples from 139 different tumor types was analyzed for STING by immunohistochemistry. STING-positive tumor cells were found in 130 (93.5%) of 139 tumor entities. The highest STING positivity rates occurred in squamous cell carcinomas (up to 96%); malignant mesothelioma (88.5%-95.7%); adenocarcinoma of the pancreas (94.9%), lung (90.3%), cervix (90.0%), colorectum (75.2%), and gallbladder (68.8%); and serous high-grade ovarian cancer (86.0%). High STING expression was linked to adverse phenotypes in breast cancer, clear cell renal cell carcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, and papillary carcinoma of the thyroid (p < 0.05). In pTa urothelial carcinomas, STING expression was associated with low-grade carcinoma (p = 0.0002). Across all tumors, STING expression paralleled PD-L1 positivity of tumor and inflammatory cells (p < 0.0001 each) but was unrelated to the density of CD8+ lymphocytes. STING expression is variable across tumor types and may be related to aggressive tumor phenotype and PD-L1 positivity. The lack of relationship with tumor-infiltrating CD8+ lymphocytes argues against a significant IFN production by STING positive tumor cells.

Comprehensive Immunohistochemical Analysis of Epithelial-Mesenchymal Transition Biomarkers in the Invasive Micropapillary Cancer of the Breast

Background: Invasive micropapillary carcinoma (IMPC) of the breast is commonly associated with a poor prognosis due to its high incidence of lymphovascular invasion and lymph node metastasis (LNM). Our study is aimed at investigating the prognostic significance of the expressions of E-cadherin (E-cad), N-cadherin (N-cad), CD44s, and β-catenin (β-cat). In addition, it is aimed at deciphering the consistency of these markers between the IMPC, the invasive breast carcinoma, no-special type (IBC-NST), and LNM components in the same IMPC cases. Methods: Sixty-two IMPC cases with LNM from 1996 to 2018 were analyzed. Immunohistochemical staining was performed separately on the three regions for each patient. Statistical analyses included Kaplan-Meier, Cox regression, and McNemar's statistical tests. Results: Loss of CD44 expression in IMPC, IBC-NST, and LNM areas was associated with poor prognosis in overall survival (OS) (p = 0.010, p < 0.0005, p = 0.025). Loss of CD44 expression in the IBC-NST, gain of N-cad expression in the IMPC, and loss of β-cat expression in the LNM areas were indicators of poor prognosis in disease-free survival (DFS) (p = 0.005, p = 0.041, p = 0.009). Conclusion: Our evaluation of this rare subtype, focusing on the expression of key epithelial-mesenchymal transition (EMT) molecules, revealed that it shares characteristics with the IBC-NST component within mixed tumors. Notably, contrary to expectations, a reduction in CD44 expression was found to adversely affect both OS and DFS. By conducting staining procedures simultaneously across three regions within the same patient, a novel approach has provided valuable insights into the mechanisms of EMT.

CEA (CEACAM5) expression is common in muscle-invasive urothelial carcinoma of the bladder but unrelated to the disease course

Objectives

Carcinoembryonic antigen (CEA) is a cell surface glycoprotein that represents a promising therapeutic target. Serum measurement of shedded CEA can be utilized for monitoring of cancer patients.

Material and Methods

To evaluate the potential clinical significance of CEA expression in urothelial bladder neoplasms, CEA was analysed by immunohistochemistry in more than 2500 urothelial bladder carcinomas in a tissue microarray format.

Results

CEA staining was largely absent in normal urothelial cells but was observed in 30.4% of urothelial bladder carcinomas including 406 (16.7%) with weak, 140 (5.8%) with moderate, and 192 (7.9%) with strong staining. CEA positivity occurred in 10.9% of 411 pTaG2 low-grade, 32.0% of 178 pTaG2 high-grade, and 43.0% of 93 pTaG3 tumours (p < 0.0001). In 1335 pT2-4 carcinomas, CEA positivity (34.1%) was lower than in pTaG3 tumours. Within pT2-4 carcinomas, CEA staining was unrelated to pT, pN, grade, L-status, V-status, overall survival, recurrence free survival, and cancer specific survival (p > 0.25).

Conclusion

CEA increases markedly with grade progression in pTa tumours, and expression occurs in a significant fraction of pT2-4 urothelial bladder carcinomas. The high rate of CEA positivity in pT2-4 carcinomas offers the opportunity of using CEA serum measurement for monitoring the clinical course of these cancers. Moreover, CEA positive urothelial carcinomas are candidates for a treatment by targeted anti-CEA drugs.

Epithelial Cell Adhesion Molecule (EpCAM) Expression in Human Tumors: A Comparison with Pan-Cytokeratin and TROP2 in 14,832 Tumors

EpCAM is expressed in many epithelial tumors and is used for the distinction of malignant mesotheliomas from adenocarcinomas and as a surrogate pan-epithelial marker. A tissue microarray containing 14,832 samples from 120 different tumor categories was analyzed by immunohistochemistry. EpCAM staining was compared with TROP2 and CKpan. EpCAM staining was detectable in 99 tumor categories. Among 78 epithelial tumor types, the EpCAM positivity rate was ≥90% in 60 categories-including adenocarcinomas, neuroendocrine neoplasms, and germ cell tumors. EpCAM staining was the lowest in hepatocellular carcinomas, adrenocortical tumors, renal cell neoplasms, and in poorly differentiated carcinomas. A comparison of EpCAM and CKpan staining identified a high concordance but EpCAM was higher in testicular seminomas and neuroendocrine neoplasms and CKpan in hepatocellular carcinomas, mesotheliomas, and poorly differentiated non-neuroendocrine tumors. A comparison of EpCAM and TROP2 revealed a higher rate of TROP2 positivity in squamous cell carcinomas and lower rates in many gastrointestinal adenocarcinomas, testicular germ cell tumors, neuroendocrine neoplasms, and renal cell tumors. These data confirm EpCAM as a surrogate epithelial marker for adenocarcinomas and its diagnostic utility for the distinction of malignant mesotheliomas. In comparison to CKpan and TROP2 antibodies, EpCAM staining is particularly common in seminomas and in neuroendocrine neoplasms.

Spatial Biology of Breast Cancer

Spatial findings have shaped on our understanding of breast cancer. In this review, we discuss how spatial methods, including spatial transcriptomics and proteomics and the resultant understanding of spatial relationships, have contributed to concepts regarding cancer progression and treatment. In addition to discussing traditional approaches, we examine how emerging multiplex imaging technologies have contributed to the field and how they might influence future research.

CHRNA6 RNA In Situ Hybridization Is a Useful Tool for the Diagnosis of Extraskeletal Myxoid Chondrosarcoma

Extraskeletal myxoid chondrosarcoma (EMC) is an uncommon mesenchymal neoplasm characteristically composed of uniform-appearing round to spindle-shaped cells with eosinophilic cytoplasm and abundant myxoid extracellular matrix. Although the majority of cases harbor a pathognomonic t(9;22) translocation that fuses EWSR1 with the orphan nuclear receptor NR4A3, there are less common variants that partner NR4A3 with TAF15, TCF12, or TFG. By immunohistochemistry, EMC has features of both cartilaginous and neuroendocrine differentiation, as evidenced by inconsistent expression of S100 protein and synaptophysin or INSM1, respectively, in a subset of cases. Given the limitations of available immunohistochemical stains for the diagnosis of EMC, we analyzed genome-wide gene expression microarray data to identify candidate biomarkers based on differential expression in EMC in comparison with other mesenchymal neoplasms. This analysis pointed to CHRNA6 as the gene with the highest relative expression in EMC (96-fold; P = 8.2 × 10-26) and the only gene with >50-fold increased expression in EMC compared with other tumors. Using RNA chromogenic in situ hybridization, we observed strong and diffuse expression of CHRNA6 in 25 cases of EMC, including both EWSR1-rearranged and TAF15-rearranged variants. All examined cases of histologic mimics were negative for CHRNA6 overexpression; however, limited CHRNA6 expression, not reaching a threshold of >5 puncta or 1 aggregate of chromogen in >25% of cells, was observed in 69 of 685 mimics (10.1%), spanning an array of mesenchymal tumors. Taken together, these findings suggest that, with careful interpretation and the use of appropriate thresholds, CHRNA6 RNA chromogenic in situ hybridization is a potentially useful ancillary histologic tool for the diagnosis of EMC.

PD-L1 expression in tumor and inflammatory cells is associated with favorable tumor features and favorable prognosis in muscle-invasive urothelial carcinoma of the bladder not treated by immune checkpoint inhibitors

BACKGROUND

A high level of PD-L1 expression is the most relevant predictive parameter for response to immune checkpoint inhibitor (CPI) therapy in urinary bladder cancer. Existing data on the relationship between PD-L1 expression and the natural course of disease are controversial and sparse.

METHODS

To expand our understanding of the relationship between PD-L1 expression and parameters of cancer aggressiveness, PD-L1 was analyzed on tissue microarrays containing 2710 urothelial bladder carcinomas including 512 patients with follow-up data who underwent radical cystectomy and follow-up therapies in the pre-immune checkpoint inhibitor therapy era.

RESULTS

Tumor cell positivity in ≥10% of cells were seen in 513 (20%) and an immune cell positivity occurred in 872 (34%) of 2566 interpretable cancers. PD-L1 positivity in tumor cells increased from pTaG2 low grade (0.9% positive) to pTaG3 high grade (4.1%; p = 0.0255) and was even higher in muscle-invasive (pT2-4) carcinomas (29.3%; p < 0.0001). However, within pT2-4 carcinomas, PD-L1 positivity was linked to low pT stage (p = 0.0028), pN0 (p < 0.0001), L0 status (p = 0.0005), and a better prognosis within 512 patients with cystectomy who never received CPIs (p = 0.0073 for tumor cells and p = 0.0086 for inflammatory cells). PD-L1 staining in inflammatory cells was significantly linked to PD-L1 staining in tumor cells (p < 0.0001) and both were linked to a positive p53 immunostaining (p < 0.0001).

CONCLUSION

It cannot be fully excluded that the strong statistical link between PD-L1 status and favorable histological tumor features as well as better prognosis could influence the outcome of studies evaluating CPIs in muscle-invasive urothelial carcinoma.

CD10 Expression Correlates with Earlier Tumour Stages and Left-Sided Tumour Location in Colorectal Cancer but Has No Prognostic Impact in a European Cohort

The role of CD10 expression in colorectal cancer has been controversially discussed in the literature. Some data suggest a predictive capacity for lymph node and liver metastases, thus influencing overall survival (OS) and disease-free survival (DFS). This study aims to analyse the relationship between CD10 expression and overall survival (OS) in a European cohort. To determine the association of CD10 expression with tumour phenotype, molecular features, and prognosis, a tissue microarray of 1469 colorectal carcinomas was analysed using immunohistochemistry and was compared with matched clinicopathologic data. CD10 expression correlated with earlier tumour stages (p = 0.017) and left-sided colon cancer (p < 0.001). However, no correlation was found between CD10 expression and lymph node involvement (p = 0.711), tumour grading (p = 0.397), or overall survival (p = 0.562). Even in the subgroup analysis of tumour or nodal stage, CD10 did not affect overall survival, although it was significantly associated with p53 and nuclear β-catenin expression (p = 0.013 and p < 0.001, respectively). CD10 expression correlates with earlier tumour stages, colon cancer location, and indicators of aggressive CRC subtypes. However, we can exclude CD10 as a relevant independent prognosticator for CRC.

Cadherin-17 (CDH17) expression in human cancer: A tissue microarray study on 18,131 tumors

Cadherin-17 (CDH17) is a membranous cell adhesion protein predominantly expressed in intestinal epithelial cells. CDH17 is therefore considered a possible diagnostic and therapeutic target. This study was to comprehensively determine the expression of CDH17 in cancer and to further assess the diagnostic utility of CDH17 immunohistochemistry (IHC). A tissue microarray containing 14,948 interpretable samples from 150 different tumor types and subtypes as well as 76 different normal tissue types was analyzed by IHC. In normal tissues, a membranous CDH17 staining was predominantly seen in the epithelium of the intestine and pancreatic excretory ducts. In tumors, 53 of 150 analyzed categories showed CDH17 positivity including 26 categories with at least one strongly positive case. CDH17 positivity was most common in epithelial and neuroendocrine colorectal neoplasms (50.0%-100%), other gastrointestinal adenocarcinomas (42.7%-61.6%), mucinous ovarian cancer (61.1%), pancreatic acinar cell carcinoma (28.6%), cervical adenocarcinoma (52.6%), bilio-pancreatic adenocarcinomas (40.5-69.8%), and other neuroendocrine neoplasms (5.6%-100%). OnIy 9.9% of 182 pulmonary adenocarcinomas were CDH17 positive. In colorectal adenocarcinomas, reduced CDH17 staining was linked to high pT (p = 0.0147), nodal metastasis (p = 0.0041), V1 (p = 0.0025), L1 (p = 0.0054), location in the right colon (p = 0.0033), and microsatellite instability (p < 0.0001). The CDH17 expression level was unrelated to tumor phenotype in gastric and pancreatic cancer. In summary, our comprehensive overview on CDH17 expression in human tumors identified various tumor entities that might often benefit from anti-CDH17 therapies and suggest utility of CDH17 IHC for the distinction of metastatic gastrointestinal or bilio-pancreatic adenocarcinomas (often positive) from primary pulmonary adenocarcinomas (mostly negative).

GAD2 Is a Highly Specific Marker for Neuroendocrine Neoplasms of the Pancreas

Glutamate decarboxylase 2 (GAD2) is the most important inhibitory neurotransmitter and plays a role in insulin-producing β cells of pancreatic islets. The limitation of GAD2 expression to a few normal cell types makes GAD2 a potential immunohistochemical diagnostic marker. To evaluate the diagnostic utility of GAD2 immunohistochemistry, a tissue microarray containing 19,202 samples from 152 different tumor entities and 608 samples of 76 different normal tissue types was analyzed. In normal tissues, GAD2 staining was restricted to brain and pancreatic islet cells. GAD2 staining was seen in 20 (13.2%) of 152 tumor categories, including 5 (3.3%) tumor categories containing at least 1 strongly positive case. GAD2 immunostaining was most commonly seen in neuroendocrine carcinomas (58.3%) and neuroendocrine tumors (63.2%) of the pancreas, followed by granular cell tumors (37.0%) and neuroendocrine tumors of the lung (11.1%). GAD2 was only occasionally (<10% of cases) seen in 16 other tumor entities including paraganglioma, medullary thyroid carcinoma, and small cell neuroendocrine carcinoma of the urinary bladder. Data on GAD2 and progesterone receptor (PR) expression (from a previous study) were available for 95 pancreatic and 380 extrapancreatic neuroendocrine neoplasms. For determining a pancreatic origin of a neuroendocrine neoplasm, the sensitivity of GAD2 was 64.2% and specificity 96.3%, while the sensitivity of PR was 56.8% and specificity 92.6%. The combination of PR and GAD2 increased both sensitivity and specificity. GAD2 immunohistochemistry is a highly useful diagnostic tool for the identification of pancreatic origin in case of neuroendocrine neoplasms with unknown site of origin.

Clinicopathological Implications of Mismatch Repair Status in Endometrioid Endometrial Cancer in Duhok City

BACKGROUND

DNA mismatch repair (MMR) is a specialized system that corrects errors in DNA replication, namely, base substitution mismatches and minor insertion-deletion mismatches. The deficient mismatch repair (d-MMR) protein plays a vital role in predicting the prognosis of endometrioid carcinoma. The study aimed to determine the prevalence of MMR errors in endometrial cancer (EC) and their correlation with clinicopathological features.

METHODS

We examined the immunohistochemistry presence of four MMR proteins in 50 samples of EC tissues that were preserved in formalin and embedded in paraffin. The proteins identified were MutL homolog 1 (MLH1), post-meiotic segregation increased 2 (PMS2), MutS homolog 2 (MSH2), and MutS homolog 6 (MSH6). The study examined several clinicopathological characteristics and conducted MMR phenotyping.

RESULTS

The findings revealed that among the 50 cases of EC, 40% of patients had grade I disease and 78% had stage I malignancy. Furthermore, among the 50 individuals evaluated, 56% exhibited competence in MMR, whereas 44% displayed loss in nuclear expression of MMR. The rate of MLH1 and PMS2 protein loss was recorded as the greatest, at 18%, while the loss of MSH2 and MSH6 was documented at 6%. Within the same range, the majority of patients with d-MMR were above the age of 50 years.

CONCLUSION

The majority of the recruited EC patients in this study showed advanced age and a high percentage of d-MMR status.

The impact of vascular division sequence and epithelial-mesenchymal transition status on postoperative recurrence in lung adenocarcinoma

BACKGROUND

The vascular division sequence in video-assisted thoracic surgery (VATS) lung resection is usually determined by the handling difficulty due to the limited surgical view through the scope. However, upfront pulmonary vein division is theoretically desirable to avoid tumor cells spreading by surgical manipulation. Epithelial-mesenchymal transition (EMT) is associated with poor prognosis and an increased number of circulating tumor cells. The purpose of this study is to evaluate the effect of vascular division sequence and EMT on postoperative recurrence.

METHODS

We retrospectively investigated tissue microarrays of 282 lung adenocarcinomas surgically resected between 2001 and 2007. We excluded the cases with segmentectomy, wedge resection, dissemination, insufficient material for staining, or lack of medical records. The effect of vascular division sequence and clinicopathologic factors on recurrence was evaluated in 195 cases.

RESULTS

The upfront pulmonary vein division (V-first) was performed in 60 patients, and the upfront pulmonary artery division (A-first) was performed in 135 patients. The recurrence was observed in 67 patients (13 in V-first and 54 in A-first). Epithelial-mesenchymal transition activation was observed in 104 patients. Multivariable analysis with 195 patients revealed that lymph node metastasis and pleural invasion were risk factors for the recurrence. The stratified multivariable analysis showed that vascular division sequence (A-first) was a risk factor only in the EMT-negative group (91 patients). In the EMT-negative subset, the 5-year relapse-free survival rate was significantly lower in the A-first group than the V-first group (72.6% vs. 92.2%, p  =  0.0136).

CONCLUSIONS

The upfront pulmonary artery division might be a risk factor in patients without EMT activation.

Loss of Upk1a and Upk1b expression is linked to stage progression in urothelial carcinoma of the bladder

BACKGROUND

Uroplakin-1a (Upk1a) and uroplakin-1b (Upk1b) have recently been identified as diagnostic markers for the distinction of urothelial carcinomas from other solid tumor entities. Both proteins play an important role in the stabilization and strengthening of epithelial cells that line the bladder.

METHODS

To evaluate the prognostic role of uroplakin expression in urothelial carcinomas, more than 2700 urothelial neoplasms were analyzed in a tissue microarray format by immunohistochemistry. To further assess the diagnostic role of uroplakin immunohistochemistry, results were compared with preexisting GATA3 data.

RESULT

The fraction of Upk1a/Upk1b positive cases decreased slightly from pTaG2 low-grade (88% positive for Upk1a/87% positive for Upk1b) and pTaG2 high-grade (92%/89%) to pTaG3 (83%/88%; p > 0.05) and was lower in muscle-invasive (pT2-4) carcinomas (42%/64%; p < 0.0001/p < 0.0001 for pTa vs. pT2-4). Within pT2-4 carcinomas, high expression of Upk1a and Upk1b was linked to nodal metastasis and lymphatic vessel infiltration (p < 0.05) but unrelated to patient outcome. There were significant associations between Upk1a, Upk1b and GATA3 immunostaining (p < 0.0001 each), but 11% of GATA3 negative cancers were Upk1a/b positive and 8% of Upk1a/b negative cancers were GATA3 positive. Absence of GATA3/Upk1a/b staining was significantly linked to poor patient survival in the subgroup of 126 pT4 carcinomas (p = 0.0004) but not in pT2 and pT3 cancers.

CONCLUSIONS

In summary, the results of our study demonstrate that Upk1a and/or Upk1b immunohistochemistry can complement GATA3 for the distinction of urothelial carcinomas. Furthermore, a progressive loss of Upk1a/b expression during stage progression and a prognostic role of the combination GATA3/Upk1a/Upk1b in pT4 carcinomas is evident.

Comparison of INSM1 immunostaining with established neuroendocrine markers synaptophysin and chromogranin A in over 14,000 neuroendocrine and non-neuroendocrine tumors

INSM1 is a transcription factor protein which is increasingly used as an immunohistochemical marker for neuroendocrine differentiation. To determine the prevalence of INSM1 expression in tumors and its expression pattern in normal tissues, tissue microarrays containing 14,908 samples from 117 different tumor types/subtypes as well as 76 different normal tissues were analyzed by immunohistochemistry. INSM1 was positive in 89.2% of 471 neuroendocrine neoplasms (NEN) and in 3.5% of 11,815 non-neuroendocrine neoplasms that were successfully analyzed. At least an occasional weak INSM1 positivity was observed in 59 different non-neuroendocrine tumor entities, of which 15 entities contained at least one case with strong INSM1 staining. A comparison with synaptophysin and chromogranin A staining revealed that in NEN, synaptophysin showed the highest sensitivity (93.3%), followed by INSM1 (89.2%) and chromogranin A (87.5%). In neuroendocrine carcinomas (NEC), sensitivity was highest for INSM1 (88.0%), followed by synaptophysin (86.5%) and chromogranin A (66.4%). If INSM1 was used as an additional marker, the sensitivity for detecting neuroendocrine differentiation in NEN increased from 96.6% (synaptophysin and chromogranin A) to 97.2% (synaptophysin, chromogranin A and INSM1). Our study shows that INSM1 is a useful additional marker for neuroendocrine differentiation with high sensitivity, particularly in NEC.

Loss of TROP2 and epithelial cell adhesion molecule expression is linked to grade progression in pTa but unrelated to disease outcome in pT2-4 urothelial bladder carcinomas

Introduction

Trophoblast cell surface antigen 2 (TROP2; EpCAM2) is a transmembrane glycoprotein which is closely related to EpCAM (EpCAM; EpCAM1). Both proteins share partial overlapping functions in epithelial development and EpCAM expression but have not been comparatively analyzed together in bladder carcinomas. TROP2 constitutes the target for the antibody-drug conjugate Sacituzumab govitecan (SG; TrodelvyTM) which has been approved for treatment of metastatic urothelial carcinoma by the United States Food and Drug administration (FDA) irrespective of its TROP2 expression status.

Methods

To evaluate the potential clinical significance of subtle differences in TROP2 and EpCAM expression in urothelial bladder cancer, both proteins were analyzed by multiplex fluorescence immunohistochemistry in combination with a deep-learning based algorithm for automated cell detection on more than 2,700 urothelial bladder carcinomas in a tissue microarray (TMA) format.

Results

The staining pattern of TROP2 and EpCAM were highly similar. For both proteins, the staining intensity gradually decreased from pTa G2 low grade (TROP2: 68.8±36.1; EpCAM: 21.5±11.7) to pTa G2 high grade (64.6±38.0; 19.3±12.2) and pTa G3 (52.1±38.7; 16.0±13.0, p<0.001 each). In pT2-4 carcinomas, the average TROP2 and EpCAM staining intensity was intermediate (61.8±40.9; 18.3±12.3). For both proteins, this was significantly lower than in pTa G2 low grade (p<0.001 each) but also higher than in pTa G3 tumors (p=0.022 for TROP2, p=0.071 for EpCAM). Within pT2-4 carcinomas, the TROP2 and EpCAM staining level was unrelated to pT, grade, UICC-category, and overall or tumor-specific patient survival. The ratio TROP2/EpCAM was unrelated to malignant phenotype and patient prognosis.

Conclusion

Our data show that TROP2 and EpCAM expression is common and highly interrelated in urothelial neoplasms. Despite of a progressive loss of TROP2/EpCAM during tumor cell dedifferentiation in pTa tumors, the lack of associations with clinicopathological parameters in pT2-4 cancer argues against a major cancer driving role of both proteins for the progression of urothelial neoplasms.

Tumor Heterogeneity Confounds Lymphocyte Metrics in Diagnostic Lung Cancer Biopsies

CONTEXT.—

The immune microenvironment is involved in fundamental aspects of tumorigenesis, and immune scores are now being developed for clinical diagnostics.

OBJECTIVE.—

To evaluate how well small diagnostic biopsies and tissue microarrays (TMAs) reflect immune cell infiltration compared to the whole tumor slide, in tissue from patients with non-small cell lung cancer.

DESIGN.—

A TMA was constructed comprising tissue from surgical resection specimens of 58 patients with non-small cell lung cancer, with available preoperative biopsy material. Whole sections, biopsies, and TMA were stained for the pan-T lymphocyte marker CD3 to determine densities of tumor-infiltrating lymphocytes. Immune cell infiltration was assessed semiquantitatively as well as objectively with a microscopic grid count. For 19 of the cases, RNA sequencing data were available.

RESULTS.—

The semiquantitative comparison of immune cell infiltration between the whole section and the biopsy displayed fair agreement (intraclass correlation coefficient [ICC], 0.29; P = .01; CI, 0.03-0.51). In contrast, the TMA showed substantial agreement compared with the whole slide (ICC, 0.64; P < .001; CI, 0.39-0.79). The grid-based method did not enhance the agreement between the different tissue materials. The comparison of CD3 RNA sequencing data with CD3 cell annotations confirmed the poor representativity of biopsies as well as the stronger correlation for the TMA cores.

CONCLUSIONS.—

Although overall lymphocyte infiltration is relatively well represented on TMAs, the representativity in diagnostic lung cancer biopsies is poor. This finding challenges the concept of using biopsies to establish immune scores as prognostic or predictive biomarkers for diagnostic applications.

FISH analysis reveals CDKN2A and IFNA14 co-deletion is heterogeneous and is a prominent feature of glioblastoma

Deletion of CDKN2A occurs in 50% of glioblastomas (GBM), and IFNA locus deletion in 25%. These genes reside closely on chromosome 9. We investigated whether CDKN2A and IFNA were co-deleted within the same heterogeneous tumour and their prognostic implications. We assessed CDKN2A and IFNA14 deletions in 45 glioma samples using an in-house three-colour FISH probe. We examined the correlation between p16INK4a protein expression (via IHC) and CDKN2A deletion along with the impact of these genomic events on patient survival. FISH analyses demonstrated that grades II and III had either wildtype (wt) or amplified CDKN2A/IFNA14, whilst 44% of GBMs harboured homozygous deletions of both genes. Cores with CDKN2A homozygous deletion (n = 11) were negative for p16INK4a. Twenty p16INK4a positive samples lacked CDKN2A deletion with some of cells showing negative p16INK4a. There was heterogeneity in IFNA14/CDKN2A ploidy within each GBM. Survival analyses of primary GBMs suggested a positive association between increased p16INK4a and longer survival; this persisted when considering CDKN2A/IFNA14 status. Furthermore, wt (intact) CDKN2A/IFNA14 were found to be associated with longer survival in recurrent GBMs. Our data suggest that co-deletion of CDKN2A/IFNA14 in GBM negatively correlates with survival and CDKN2A-wt status correlated with longer survival, and with second surgery, itself a marker for improved patient outcomes.

Methylation-Specific Electrophoresis

Methylation of CpG sites in the promoter region of genomic DNA is an important epigenetic modification that plays a critical role in gene regulation, particularly in gene silencing. Epigenetic abnormalities, along with genetic alterations, are implicated in carcinogenesis and cancer progression. Numerous studies have investigated the role of epigenetics in cancer using various tools to assess DNA methylation. However, conventional analysis methods for DNA methylation require a large amount of DNA but lack higher sensitivity, making them unsuitable for analysis of samples with high heterogeneity, such as tumor tissues. In this study, we introduce a novel electrophoresis method named "methylation-specific electrophoresis (MSE)," which utilizes a denaturing gradient acrylamide gel. We demonstrate the applicability of the MSE method for DNA methylation analysis of the mucin gene as an example.