Association of homozygous variants of STING1 with outcome in human cervical cancer.

DNA-sensing receptor Cyclic GMP-AMP Synthase (cGAS) and its downstream signaling effector STimulator of INterferon Genes (STING) have gained significant interest in the field of tumor immunology, as a dysfunctional cGAS-STING pathway is associated with poor prognosis and worse response to immunotherapy. However, studies so far have not taken into account the polymorphic nature of the STING-encoding STING1 gene. We hypothesized that the presence of allelic variance in STING1 would cause variation between individuals as to their susceptibility to cancer development, cancer progression, and potential response to (immuno)therapy. To start to address this, we defined the genetic landscapes of STING1 in cervical scrapings and investigated their corresponding clinical characteristics across a unique cohort of cervical cancer patients and compared them with independent control cohorts. Although we did not observe an enrichment of particular STING1 allelic variants in cervical cancer patients, we did find that the occurrence of homozygous variants HAQ/HAQ and R232H/R232H of STING1 were associated with both younger age of diagnosis and higher recurrence rate. These findings were accompanied by worse survival, despite comparable mRNA and protein levels of STING and numbers of infiltrated CD8+ T cells. Our findings suggest that patients with HAQ/HAQ and R232H/R232H genotypes may have a dysfunctional cGAS-STING pathway that fails to promote efficient anticancer immunity. Interestingly, the occurrence of these genotypes coincided with homozygous presence of the V48V variant, which was found to be individually associated with worse outcome. Therefore, we propose V48V to be further evaluated as a novel prognostic marker for cervical cancer.

A case report of an unusual non-mucinous papillary variant of CPAM type 1 with KRAS mutations.

BACKGROUND: congenital pulmonary airway malformation (CPAM) is the most frequent congenital lung disorder. CPAM type 1 is the most common subtype, typically having a cystic radiological and histological appearance. Mucinous clusters in CPAM type 1 have been identified as premalignant precursors for mucinous adenocarcinoma. These mucinous adenocarcinomas and the mucinous clusters in CPAM commonly harbor a specific KRAS mutation. CASE PRESENTATION: we present a case of a 6-weeks-old girl with CPAM type 1 where evaluation after lobectomy revealed a highly unusual complex non-mucinous papillary architecture in all cystic parts, in which both mucinous clusters and non-mucinous papillary areas harbored the known KRAS mutation. CONCLUSIONS: we found that a KRAS mutation thought to be premalignant in mucinous clusters only, was also present in the other cyst lining epithelial cells of this unusual non-mucinous papillary variant of CPAM type 1, warranting clinical follow-up because of uncertain malignant potential.

Robot-Assisted Laparoscopic Resection of a Todani Type II Choledochal Malformation.

Choledochal malformation (CM) comprise various congenital cystic dilatations of the extrahepatic and/or intrahepatic biliary tree. CM is classified into five different types. Our case describes a 58-year-old man presenting with acute abdominal pain. Further examination showed a Todani type II CM. Treatment for type II is complete cyst excision without the need for an extrahepatic bile duct resection. A robot-assisted laparoscopic resection of the CM was performed and the patient recovered without complications. Pathology results showed a Todani type II malformation in which complete squamous metaplasia has occurred. In this paper, we report, to the best of our knowledge, the first description of a robot-assisted laparoscopic resection of a type II CM.

What is the added value of digital image analysis of HER2 immunohistochemistry in breast cancer in clinical practice? A study with multiple platforms.

AIMS: We aimed to compare digital image analysis (DIA) of human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) in breast cancer by two platforms: (i) to validate DIA against standard diagnostics; and (ii) to evaluate the added value of DIA in clinical practice. METHODS AND RESULTS: HER2 IHC and in-situ hybridisation (ISH) were performed on 152 consecutive invasive breast carcinomas. IHC scores were determined with DIA using two independent platforms. Manual scoring was performed by two independent observers. HER2 status was considered positive in 3+ and ISH-positive 2+ cases. HER2 status using DIA was compared to HER2 status with standard diagnostics (manual scoring with ISH in 2+ cases). Interplatform agreement of IHC scores was 'moderate' (linear weighted κ = 0.58), agreement between manual scoring and platform A was 'moderate' (κ = 0.60) and between manual scoring and platform B 'almost perfect' (κ = 0.85). Compared to manual scoring, DIA resulted in a reduction of 2+ cases from 17.1 to 1.3% with platform A and from 17.1 to 15.8% with platform B. However, compared to standard diagnostics, there were three false-negative cases with DIA using platform A [81.3% sensitivity, 100% specificity, 100% positive predictive value (PPV), 97.8% negative predictive value (NPV)]. Sensitivity, specificity, PPV and NPV were 100% with DIA using platform B. CONCLUSIONS: DIA of HER2 IHC is a valid tool in determining HER2 status in breast carcinoma. Algorithms in different platforms can behave differently, and optimal calibration is essential. In clinical practice, DIA offers an objective alternative to manual scoring, but a reduction in 2+ cases could result in loss of sensitivity.

HER2 immunohistochemistry in endometrial and ovarian clear cell carcinoma: discordance between antibodies and with in-situ hybridisation.

AIMS: Treatment with anti-HER2 therapy could be beneficial for patients with HER2-positive endometrial and ovarian clear cell carcinoma (CCC). We studied HER2 overexpression by immunohistochemistry (IHC) using three different antibodies, including concordance with amplification by in-situ hybridisation (ISH). METHODS AND RESULTS: IHC and ISH were performed on tissue microarrays of 101 tumours: 58 endometrial pure CCC, 19 endometrial mixed carcinomas with a CCC component and 24 ovarian pure CCC. IHC was performed using SP3, 4B5 and HercepTest antibodies, and was scored by two independent observers. ISH was performed using dual-colour silver ISH. Using IHC, agreement was poor between SP3/4B5 (61.4%), poor between SP3/HercepTest (68.3%) and reasonable between 4B5/HercepTest (75.2%). Interobserver agreement was substantial to almost perfect for all antibodies (SP3: linear weighted κ = 0.89, 4B5: κ = 0.90, HercepTest: κ = 0.76). HER2-positivity by ISH was 17.8% (endometrial pure CCC: 24.1%, endometrial mixed: 0%, ovarian pure CCC: 16.7%). IHC/ISH concordance was poor, with a high false-negative rate of all three IHC antibodies: sensitivity (38.9-50.0%) and positive predictive value (PPV) (37.5-58.3%) were poor; specificity (81.9-94.0%) and negative predictive value (NPV) (87.1-88.3%) were reasonable. When excluding 2+ cases, sensitivity declined (26.7-43.8%) but PPV (80.0-87.5%) and specificity (98.6-98.7%) improved. CONCLUSIONS: In ovarian and endometrial CCC, there is considerable difference in HER2 overexpression by different IHC antibodies and marked discordance with ISH. As such, no single antibody can be considered conclusive for determining HER2 status in CCC. Based on these results, the lack of predictive value of different HER2 testing methods, as used in other studies, could be explained.

Digital image analysis of Ki67 proliferation index in breast cancer using virtual dual staining on whole tissue sections: clinical validation and inter-platform agreement.

PURPOSE: The Ki67 proliferation index is a prognostic and predictive marker in breast cancer. Manual scoring is prone to inter- and intra-observer variability. The aims of this study were to clinically validate digital image analysis (DIA) of Ki67 using virtual dual staining (VDS) on whole tissue sections and to assess inter-platform agreement between two independent DIA platforms. METHODS: Serial whole tissue sections of 154 consecutive invasive breast carcinomas were stained for Ki67 and cytokeratin 8/18 with immunohistochemistry in a clinical setting. Ki67 proliferation index was determined using two independent DIA platforms, implementing VDS to identify tumor tissue. Manual Ki67 score was determined using a standardized manual counting protocol. Inter-observer agreement between manual and DIA scores and inter-platform agreement between both DIA platforms were determined and calculated using Spearman's correlation coefficients. Correlations and agreement were assessed with scatterplots and Bland-Altman plots. RESULTS: Spearman's correlation coefficients were 0.94 (p < 0.001) for inter-observer agreement between manual counting and platform A, 0.93 (p < 0.001) between manual counting and platform B, and 0.96 (p < 0.001) for inter-platform agreement. Scatterplots and Bland-Altman plots revealed no skewness within specific data ranges. In the few cases with ≥ 10% difference between manual counting and DIA, results by both platforms were similar. CONCLUSIONS: DIA using VDS is an accurate method to determine the Ki67 proliferation index in breast cancer, as an alternative to manual scoring of whole sections in clinical practice. Inter-platform agreement between two different DIA platforms was excellent, suggesting vendor-independent clinical implementability.

Digital image analysis of HER2 immunohistochemistry in gastric- and oesophageal adenocarcinoma: a validation study on biopsies and surgical specimens.

AIMS: To test the validity of diagnostics incorporating digital image analysis (DIA) for human epidermal growth factor 2 (HER2) immunohistochemistry (IHC) in gastro-oesophageal adenocarcinomas, as an alternative to current standard diagnostics using manual scoring. METHODS AND RESULTS: We included 319 consecutive gastro-oesophageal adenocarcinomas (232 biopsies and 87 surgical specimens). DIA was applied to determine HER2 IHC classification, using both standard breast cancer (BC) and modified gastro-oesophageal cancer (GEC) cut-offs. Consensus manual scores were established by four independent observers. Chromogenic in-situ hybridization (CISH) was performed on all 2+ cases by manual scoring, DIA or both. HER2 status was considered positive in 3+ and CISH-positive 2+ cases. Overall agreement between DIA and consensus manual scores was 76.5% (weighted κ = 0.66, BC cut-offs) and 85.6% (weighted κ = 0.80, GEC cut-offs). Agreement was similar for biopsies and surgical specimens. All disagreement occurred in the manual IHC equivocal cases. DIA resulted in a reduction of 2+ cases: 75.8% with BC cut-offs and 46.5% with GEC cut-offs. HER2 status was positive in 48 cases (15%) with standard diagnostics and DIA using GEC cut-offs, and 46 cases (14.4%) using BC cut-offs (all with CISH in 2+ cases). Considering standard diagnostics as a reference, DIA showed 93.8% sensitivity and 99.6% specificity (BC cut-offs) or 97.9% sensitivity and 99.6% specificity (GEC cut-offs). CONCLUSIONS: DIA is a reliable and feasible alternative to manual HER2 IHC scoring in gastro-oesophageal adenocarcinoma, both in biopsies and surgical specimens, leading to a reduction of 2+ cases for which subsequent ISH testing is required.

Kidney Involvement in Systemic Calcitonin Amyloidosis Associated With Medullary Thyroid Carcinoma.

A 52-year-old woman with widely disseminated medullary thyroid carcinoma developed nephrotic syndrome and slowly decreasing kidney function. A kidney biopsy was performed to differentiate between malignancy-associated membranous glomerulopathy and tyrosine kinase inhibitor-induced focal segmental glomerulosclerosis. Surprisingly, the biopsy specimen revealed diffuse glomerular deposition of amyloid that was proved to be derived from the calcitonin hormone (Acal), produced by the medullary thyroid carcinoma. This amyloid was also present in an abdominal fat pad biopsy. Although local ACal deposition is a characteristic feature of medullary thyroid carcinoma, the systemic amyloidosis involving the kidney that is presented in this case report has not to our knowledge been described previously and may be the result of long-term high plasma calcitonin levels. Our case illustrates that systemic calcitonin amyloidosis should be considered in the differential diagnosis of proteinuria in patients with medullary thyroid carcinoma.

Pathologic diagnostics of HER2 positivity in gastroesophageal adenocarcinoma.

OBJECTIVES: The human epidermal growth factor receptor 2 (HER2) oncogene shows overexpression in 15% to 30% of gastroesophageal adenocarcinomas. Targeted anti-HER2 therapy with trastuzumab has been recently validated in advanced gastric and gastroesophageal junction cancer treatment. A standardized modified scoring system was recently introduced for gastroesophageal HER2 scoring. We aimed to validate this scoring system, including an analysis of interobserver variability of immunohistochemistry (IHC) scoring. METHODS: In total, 323 patients with histologically confirmed invasive gastric or esophageal adenocarcinoma were examined for HER2 by IHC and chromogenic in situ hybridization (CISH). IHC 3 + or IHC 2 +/CISH positive tumors were considered HER2 positive. Interobserver variability on IHC scoring using the currently standard modified HER2 scoring system was determined among three clinical pathologists. Clinicopathologic characteristics were retrospectively retrieved from the patient records. RESULTS: HER2 positivity was found in 50 (15.5%) of 323 patients. Interobserver agreement on IHC scoring was high (κ = 0.78). Most disagreement was found in diffuse or mixed tumor types and in weak to moderate stained samples (IHC 2 +). The HER2 IHC scoring system is sensitive in differentiating HER2 status before ISH. CONCLUSIONS: The currently used standardized HER2 scoring system is an excellent, clinically applicable method to establish HER2 status in appropriately educated and trained pathologists.