Cadherin-16 (CDH16) Immunohistochemistry: A Novel Diagnostic Tool for Renal Cell Carcinoma and Papillary Carcinomas of the Thyroid

Introduction/Objective

Introduction: Cadherin-16 (CDH16), also termed kidney specific cadherin (ksp-cadherin), is a membrane-associated glycoprotein with a role in the embryonal development of tubules in kidney and thyroid. Downregulation of CDH16 RNA was found in papillary carcinomas of the thyroid.

Methods/Case Report

Methods: A set of tissue microarrays containing 14,978 samples from 149 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry to determine the expression of CDH16 in cancer and to assess the diagnostic utility of immunohistochemical CDH16 analysis.

Results (if a Case Study enter NA)

Results: Among normal tissues, a membranous CDH16 immunostaining predominated in thyroid, kidney, cauda epididymis, and in mesonephric remnants. In the thyroid, CDH16 staining was seen in 100% of normal samples, 83% of follicular adenomas, 58% of follicular carcinomas, but in only 9% of papillary carcinomas (p<0.0001). Among non-thyroidal tumors, CDH16 positivity was particularly frequent in nephrogenic adenomas (100%), oncocytomas (98%), chromophobe (97%), clear cell (85%), and papillary (76%) renal cell carcinomas (RCCs), clear cell (56%), mucinous (36%), and endometroid (16%) carcinomas as well as carcinosarcomas (18%) of the ovary, adenocarcinomas of the cervix uteri (40%), serous (33%), clear cell (33%), and endometroid carcinomas (18%) of the endometrium and in various subtypes of neuroendocrine neoplasms (4-26%).

Conclusion

Given the massive loss of CDH16 expression in >90% of papillary carcinomas of the thyroid, CDH16 is a highly useful diagnostic marker for these tumors. CDH16 immunohistochemistry is also useful for the identification of nephrogenic adenomas and the distinction of renal cell carcinomas from other neoplasms.

A Comparative Analysis of CPA1, bcl10 and Chymotrypsin for the Distinction of Pancreatic Acinar Cell Carcinomas

Introduction/Objective

Introduction: Pancreatic acinar cell carcinoma (PACC) is a rare tumor of the pancreas with an intermediate prognosis as compared to pancreatic neuroendocrine tumors (PNE) and pancreatic ductal adenocarcinoma (PDAC) from which it may be difficult to distinguish by morphology alone.

Methods/Case Report

Methods: To study was the efficiency of immunohistochemical markers, 18 PACCs, 531 PDACs, 64 PNEs, 117 extra pancreatic neuroendocrine neoplasms (EPNN), 826 colorectal carcinomas (CRC) and 252 gastric carcinomas (GC) were analyzed with antibodies for CPA1 (MSVA-601M), bcl10 (Santa Cruz sc5273), and chymotrypsin (Biorad 2100-0657) in a tissue microarray format.

Results (if a Case Study enter NA)

Results: CPA1 was positive in 18 of 18 (100%) of PACCs, 0 of 49 (0%) of PNEs, 0 of 88 (0%) of EPNNs, 10 of 404 (2.5%) of CRCs, and 0 of 178 (0%) of GCs. Chymotrypsin was positive in 16 (87,5%) PACCs, 1 (2%) PNEs, 2 (2.3%) EPNNs, 10 (2.5%) CRCs, and 1 (0.6%) GCs. Bcl10 was positive in 18 (100%) PACCs, 2 (4.1%) PNEs, 5 (1%) EPNNs, 109 (27%) CRCs, and 18 (10%) GCs. These data resulted in a sensitivity and specificity of 100%/99.2% for CPA1, 100%/88.4% for bcl10, and 94.4%/98.6% for chymotrypsin.

Conclusion

CPA1 and chymotrypsin are both highly specific and sensitive for ACC while bcl10 is sensitive but has markedly lower specificity. Because all “false positive” cases identified by CPA1 were CRCs that only showed a positive staining in goblet cells and an identical staining pattern was observed in all these cases for chymotrypsin and bcl10, a pancreatic origin of the mucus in these goblet cells is concluded.

P02.03 Automated cell type specific PD-L1 quantification by artificial intelligence using high throughput bleach & stain 15-marker multiplex fluorescence immunohistochemistry in human cancers

Background

The quantification of PD-L1 (programmed cell death ligand 1) has been used to predict patient’s survival, to characterize the tumor immune microenvironment, and to predict response to immune checkpoint therapies. However, a framework to assess the PD-L1 status with a high interobserver reproducibility on tumor cells and different types of immune cells has yet to be established.

Materials and Methods

To study the impact of PD-L1 expression on the tumor immune microenvironment and patient outcome, a framework for fully automated PD-L1 quantification on tumor cells and immune cells was established and validated. Automated PD-L1 quantification was facilitated by incorporating three different deep learning steps for the analysis of more than 80 different neoplasms from more than 10’000 tumor specimens using a bleach & stain 15-marker multiplex fluorescence immunohistochemistry panel (i.e., PD-L1, PD-1, CTLA-4, panCK, CD68, CD163, CD11c, iNOS, CD3, CD8, CD4, FOXP3, CD20, Ki67, CD31). Clinicopathological parameter were available for more than 30 tumor entities and overall survival data were available for 1517 breast cancer specimens.

Results

Comparing the automated deep-learning based PD-L1 quantification with conventional brightfield PD-L1 data revealed a high concordance in tumor cells (p<0.0001) as well as immune cells (p<0.0001) and an accuracy of the automated PD-L1 quantification ranging from 90% to 95.2%. Across all tumor entities, the PD-L1 expression level was significantly higher in distinct macrophage/dendritic cell (DC) subsets (identified by CD68, CD163, CD11c, iNOS; p<000.1) and in macrophages/DCs located in the Stroma (p<0.0001) as compared to intratumoral macrophages/DC subsets. Across all different tumor entities, the PD-L1 expression was highly variable and distinct PD-L1 driven immune phenotypes were identified based on the PD-L1 intensity on both tumor and immune cells, the distance between non-exhausted T-cell subsets (i.e. PD-1 and CTLA-4 expression on CD3+CD8+ cytotoxic T-cells, CD3+CD4+ T-helper cells, CD3+CD4+FOXP3+ regulatory T-cells) and tumor cells as well as macrophage/(DC) subtypes. In breast cancer, the PD-L1 fluorescence intensity on tumor cells showed a significantly higher predictive performance for overall survival with an area under receiver operating curves (AUC) of 0.72 (p<0.0001) than the percentage of PD-L1+ tumor cells (AUC: 0.54). In PD-L1 positive as well as negative breast cancers a close spatial relationship between T- cell subsets (CD3+CD4±CD8±FOXP3±PD-1±CTLA-4±) and Macrophage/DC subsets (CD68±CD163±CD11c±iNOS) was found prognostic relevant (p<0.0001).

Conclusions

In conclusion, multiplex immunofluorescence PD-L1 assessment provides cutoff-free/continuous PD-L1 data which are superior to the conventional percentage of PD-L1+ tumor cells and of high prognostic relevance. The combined analysis of spatial PD-L1/PD-1 data and more than 20 different immune cell subtypes of the immune tumor microenvironment revealed distinct PD-L1 immune phenotypes.

Disclosure Information

N.C. Blessin: None. E. Bady: None. T. Mandelkow: None. C. Yang: None. J. Raedler: None. R. Simon: None. C. Fraune: None. M. Lennartz: None. S. Minner: None. E. Burandt: None. D. Höflmayer: None. G. Sauter: None. S.A. Weidemann: None.

Adrenal cancer: relevance of different grading systems and subtypes

PURPOSE

The subclassification of adrenal cancers according to the WHO classification in ordinary, myxoid, oncocytic, and sarcomatoid as well as pediatric types is well established, but the criteria for each subtype are not sufficiently determined and the relative frequency of the different types of adrenal cancers has not been studied in large cohorts. Therefore, our large collection of surgically removed adrenal cancers should be reviewed o establish the criteria for the subtypes and to find out the frequency of the various types.

METHODS

In our series of 521 adrenal cancers the scoring systems of Weiss et al., Hough et al., van Slooten et al. and the new Helsinki score system were used for the ordinary type of cancer (97% of our series) and the myxoid type (0.8%). For oncocytic carcinomas (2%), the scoring system of Bisceglia et al. was applied.

RESULTS

Discrepancies between benign and malignant diagnoses from the first thee classical scoring systems are not rare (22% in our series) and could be resolved by the Helsinki score especially by Ki-67 index (more than 8% unequivocally malignant). Since all our cancer cases are positive in the Helsinki score, this system can replace the three elder systems. For identification of sarcomatoid cancer as rarest type in our series (0.2%), the scoring systems are not practical but additional immunostainings used for soft tissue tumors and in special cases molecular pathology are necessary to differentiate these cancers from adrenal sarcomas. According to the relative frequencies of the different subtypes of adrenal cancers the main type is the far most frequent (97%) followed by the oncocytic type (2%), the myxoid type (0.8%) and the very rare sarcomatoid type (0.2%).

CONCLUSIONS

The Helsinki score is the best for differentiating adrenal carcinomas of the main, the oncocytic, and the myxoid type in routine work. Additional scoring systems for these carcinomas are generally not any longer necessary. Signs of proliferation (mitoses and Ki-67 index) and necroses are the most important criteria for diagnosis of malignancy.

Commentary on "Detection and oncological effect of circulating tumor cells in patients with variant urothelial carcinoma histology treated with radical cystectomy."

OBJECTIVES

To investigate for the presence of circulating tumor cells (CTC) in patients with variant urothelial carcinoma of the bladder (UCB) histology treated with radical cystectomy (RC), and to determine their impact on oncological outcomes.

PATIENTS AND METHODS

We, prospectively, collected data of 188 patients with UCB treated with RC without neoadjuvant chemotherapy. Pathological specimens were meticulously reviewed for pure and variant UCB histology. Preoperatively collected blood samples (7.5ml) were analyzed for CTC using the CellSearch system (Janssen, Raritan, NJ).

RESULTS

Variant UCB histology was found in 47 patients (25.0%), most frequently of squamous cell differentiation (16.5%). CTC were present in 30 patients (21.3%) and 12 patients (25.5%) with pure and variant UCB histology, respectively. At a median follow-up of 25 months, the presence of CTC and nonsquamous cell differentiation were associated with reduced recurrence-free survival (RFS) and cancer-specific survival (pairwise P ≤ 0.016). Patients without CTC had better RFS, independent of UCB histology, than patients with CTC with any UCB histology (pairwise P<0.05). In multivariable analyses, the presence of CTC, but not variant UCB histology, was an independent predictor for disease recurrence (hazard ratio = 3.45, P<0.001) and cancer-specific mortality (hazard ratio = 2.62, P = 0.002).

CONCLUSION

CTC are detectable in about a quarter of patients with pure or variant UCB histology before RC, and represent an independent predictor for outcomes, when adjusting for histological subtype. In addition, our prospective data confirm the unfavorable influence of nonsquamous cell-differentiated UCB on outcomes.

Chromosomal deletions, tumor phenotype, and prognosis in prostate cancer

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Background: Chromosomal deletions are frequent in prostate cancer (PCa) but target genes and potential clinical significance are often unknown. This project aimed at the identification of frequent and new deletions in PCa and to study their association with tumor phenotype and PSA recurrence.

Methods: Array CGH was performed on 77 advanced PCa. Deletions of interest were subsequently analyzed on a tissue microarray containing more than 2000 PCa with clinical follow-up data using fluorescence in situ hybridization (FISH). The FISH probes used included a break-apart probe for TMPRSS2-ERG and dual-labeling probes for centromere 10/PTEN and centromere 3/3p14.

Results: The most frequent circumscribed deletions found by array CGH were 3p14 (including FOXP1) in 18%, 5q31 in 16%, 5q21 in 14%, 6q13 in 21%, 6q21 in 19%, 6q26 in 14%, 8p11 in 17%, 10q23 (including PTEN) in 18%, 12p13 in 14%, 13q14 in 14%, 16q24 in 22% and 21q (representing TMPRSS2-ERG fusion) in 18%. TMPRSS2-ERG fusions, PTEN and FOXP1 deletions were selected for FISH analysis. A TMPRSS2-ERG fusion was observed in 394 of 947 interpretable cases (41.6%). TMPRSS2-ERG fusion was unrelated to tumor stage, Gleason grade, and PSA recurrence. PTEN deletions were observed in 8.9% of 1844 interpretable cases and were associated with advanced tumor stage (p<0.0001), high Gleason grade (p<0.0001), and early biochemical recurrence (p<0.0001). FOXP1 deletions were seen in 5.0% of 619 cases. FOXP1 deletions were not significantly linked to tumor phenotype and outcome. Both PTEN and FOXP1 deletions were strongly linked to TMPRSS2-ERG fusions. TMPRSS2-ERG fusion positive tumors had PTEN deletions in 15.4% and FOXP1 deletions in 10.7%, while TMPRSS2-ERG fusion negative cancers had PTEN deletions in only 5.8% and FOXP1 deletions in only 2.0% of cases (p<0.0001 each).

Conclusions: The TMPRSS2-ERG fusion determines a genetically distinct subgroup of prostate cancers. Our data provide no evidence for a particular clinical behaviour of TMPRSS2-ERG fusion positive cancers in radically operated patients. PTEN and FOXP1 alterations are preferentially found in TMPRSS2-ERG fusion positive cancers. Both genes may potentially be involved in pathway dysregulation in these cancers.

No significant financial relationships to disclose.

[Primary diffuse neurofibroma of the urinary bladder: a rare case report and review of the literature]

Diffuse neurofibromas are benign mesenchymal tumours with nerve sheath differentiation. Only a few cases have been reported in the urinary bladder. We present a well-documented case report of a 62-year-old man presenting with gross haematuria and histopathological confirmation of a diffuse neurofibroma. We further reviewed the current literature with regard to clinical features and treatment options.

[Tumors of the urinary system. Current and old problems]

Principally there are two different types of bladder cancer. Non-invasive papillary low grade tumors (pTa G1-G2) are genetically stable, recur frequently but show a low risk of progression. On the other hand there are high grade tumors (pT1-4, carcinoma in situ), which are genetically unstable, show biologically aggressive behaviour and progress. The distinction between non-invasive (pTa) and minimal-invasive (pT1) is one of the most challenging areas in bladder pathology. Due to the lack of appropriate auxiliary analysis the diagnosis is based entirely on histopathology. P53 immunohistochemistry can be helpful in the assessment of recurring high grade neoplasia. Targeted therapy in bladder cancer is particularly interesting, since a high number of oncogenes are activated and overexpressed (e.g. HER2 and EGFR).

[Randomized controlled trial on vessel sealing in thyroid surgery]

AIM

To compare conventional suture ligation with vessel sealing in thyroid surgery.

METHODS

We investigated in a randomized controlled trial whether vessel sealing in thyroid surgery may shorten operative time compared to suture ligation. Included were all thyroid resections because of benign thyroid diseases. Primary endpoint was operative time and secondary endpoints were all postoperative complications.

RESULTS

150 patients were included into the study. 77 were randomized into the control group and 73 into the sealing group. Age, sex, BMI and extent of resection were not different between groups. Operative time was 10.2 min (CI - 1,3; 21,7) shorter in the sealing group. Sex, one- or two-sided resection, site of thyroid, and the experience of the surgeon had all a significant influence on operative time. Postoperative complications were not different between groups.

CONCLUSION

Vessel sealing shortens operative time, especially if resection is performed by experienced surgeons, and did not increase postoperative complication rate.

[Long-term cosmetic results following thyroid resection]

BACKGROUND

The long-term cosmetic results following thyroid resection may soon become more relevant because minimally invasive techniques are also being promoted.

PATIENTS AND METHODS

Two hundred forty-four patients were prospectively enrolled for a questionnaire regarding long-term results following thyroid resection. Ninety of these patients were clinically examined.

RESULTS

The cosmetic results were judged by more than 90% of the patients as excellent or good. Women were slightly more critical about their results (P=0.06). Some kind of wound infection was reported in 4.1%, hypertrophic scar in 4.1%, and mild dysphagia in 7%. The results were not associated with the kind or extent of resection. The length of the scars was 4 cm (range 3-7) and the width 2 mm (range 1-4). The surgeons also judged the scars as good or excellent in most cases but were more critical than the patients.

CONCLUSION

Since the long-term results of conventional surgery are, in most cases, so good, it seems difficult to improve the results by new minimally invasive techniques.