Interpretation of PD-L1 expression in gastric cancer: summary of a consensus meeting of Korean gastrointestinal pathologists

Nivolumab plus chemotherapy in the first-line setting has demonstrated clinical efficacy in patients with human epidermal growth factor receptor 2–negative advanced or metastatic gastric cancer, and is currently indicated as a standard treatment. Programmed death-ligand 1 (PD-L1) expression is an important biomarker for predicting response to anti–programmed death 1/PD-L1 agents in several solid tumors, including gastric cancer. In the CheckMate-649 trial, significant clinical improvements were observed in patients with PD-L1 combined positive score (CPS) ≥ 5, determined using the 28-8 pharmDx assay. Accordingly, an accurate interpretation of PD-L1 CPS, especially at a cutoff of 5, is important. The CPS method evaluates both immune and tumor cells and provides a comprehensive assessment of PD-L1 expression in the tumor microenvironment of gastric cancer. However, CPS evaluation has several limitations, one of which is poor interobserver concordance among pathologists. Despite these limitations, clinical indications relying on PD-L1 CPS are increasing. In response, Korean gastrointestinal pathologists held a consensus meeting for the interpretation of PD-L1 CPS in gastric cancer. Eleven pathologists reviewed 20 PD-L1 slides with a CPS cutoff close to 5, stained with the 28-8 pharmDx assay, and determined the consensus scores. The issues observed in discrepant cases were discussed. In this review, we present cases of gastric cancer with consensus PD-L1 CPS. In addition, we briefly touch upon current practices and clinical issues associated with assays used for the assessment of PD-L1 expression in gastric cancer.

Primary Cavernous Hemangioma of the Thyroid Gland

Hemangiomas are benign vascular tumors that result from the abnormal proliferation of vascular tissue. Thyroid hemangiomas can develop as a result of procedures such as fine needle aspiration or other secondary trauma.Primary thyroid cavernous hemangioma is an extremely rare condition, with only a few reported cases. In this report, we present the case of an 83-year-old woman who complained of progressively worsening symptoms of right neck obstruction. She was undergoing levothyroxine treatment for hypothyroidism, and there was no specific family history of thyroid issues. The patient presented with a goiter and obstructive symptoms, and denied any history of trauma or invasive procedures. Thyroid sonography revealed a 6.21 cm heterogeneous dominant solid nodule in the right lobe. Additionally, a large mixed cystic and 6 cm solid mass was identified in the right lobe on CT scan. Due to the significant size of the mass and the presence of obstructive symptoms, the patient underwent a right thyroid lobectomy without further evaluations. Histologic examination of the specimen revealed a cavernous thyroid hemangioma. This case report presents our experience in diagnosing cavernous thyroid hemangioma.

HER2 status in breast cancer: changes in guidelines and complicating factors for interpretation

Human epidermal growth factor receptor 2 (HER2) protein overexpression and/or HER2 gene amplification is found in about 20% of invasive breast cancers. It is a sole predictive marker for treatment benefits from HER2 targeted therapy and thus, HER2 testing is a routine practice for newly diagnosed breast cancer in pathology. Currently, HER2 immunohistochemistry (IHC) is used for a screening test, and in situ hybridization is used as a confirmation test for HER2 IHC equivocal cases. Since the American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines on HER2 testing was first released in 2007, it has been updated to provide clear instructions for HER2 testing and accurate determination of HER2 status in breast cancer. During HER2 interpretation, some pitfalls such as intratumoral HER2 heterogeneity and increase in chromosome enumeration probe 17 signals may lead to inaccurate assessment of HER2 status. Moreover, HER2 status can be altered after neoadjuvant chemotherapy or during metastatic progression, due to biologic or methodologic issues. This review addresses recent updates of ASCO/CAP guidelines and factors complicating in the interpretation of HER2 status in breast cancers.

Pancreatic Metastasis from Adenocarcinoma of the Uterine Cervix / 대한소화기학회지

Pancreatic metastasis from cervical cancer is extremely rare. We report a case of metastatic adenocarcinoma of the pancreas from uterine cervical cancer. A 70-year-old woman was referred because of a pancreatic mass detected by CT. She had been diagnosed with uterine cervical adenocarcinoma 20 months previously. After concurrent chemoradiotherapy, CT showed no evidence of the cervical mass, and follow-up showed no evidence of recurrence. Endoscopic ultrasound-guided fine needle aspiration biopsy of the pancreatic mass resulted in a diagnosis of metastatic adenocarcinoma from uterine cervix.

Aquaporin 1 Is an Independent Marker of Poor Prognosis in Lung Adenocarcinoma

BACKGROUND: Aquaporin 1 (AQP1) overexpression has been shown to be associated with uncontrolled cell replication, invasion, migration, and tumor metastasis. We aimed to evaluate AQP1 expression in lung adenocarcinomas and to examine its association with clinicopathological features and prognostic significance. We also investigated the association between AQP1 overexpression and epithelial-mesenchymal transition (EMT) markers. METHODS: We examined AQP1 expression in 505 cases of surgically resected lung adenocarcinomas acquired at the Seoul National University Bundang Hospital from 2003 to 2012. Expression of AQP1 and EMT-related markers, including Ecadherin and vimentin, were analyzed by immunohistochemistry and tissue microarray. RESULTS: AQP1 overexpression was associated with several aggressive pathological parameters, including venous invasion, lymphatic invasion, and tumor recurrence. AQP1 overexpression tended to be associated with higher histological grade, advanced pathological stage, and anaplastic lymphoma kinase (ALK) translocation; however, these differences were not statistically significant. In addition, AQP1 overexpression positively correlated with loss of E-cadherin expression and acquired expression of vimentin. Lung adenocarcinoma patients with AQP1 overexpression showed shorter progression-free survival (PFS, 46.1 months vs. 56.2 months) compared to patients without AQP1 overexpression. Multivariate analysis confirmed that AQP1 overexpression was significantly associated with shorter PFS (hazard ratio, 1.429; 95% confidence interval, 1.033 to 1.977; p=.031). CONCLUSIONS: AQP1 overexpression was thereby concluded to be an independent factor of poor prognosis associated with shorter PFS in lung adenocarcinoma. These results suggested that AQP1 overexpression might be considered as a prognostic biomarker of lung adenocarcinoma.

Serious Adverse Transfusion Reactions Reported in the National Recipient-Triggered Trace Back System in Korea (2006-2014)

BACKGROUND: Adverse transfusion reactions (ATRs) are clinically relevant to patients with significant morbidity and mortality. This study aimed to review the cases of ATR reported in the recipient-triggered trace back system for a recent nine-year period in Korea. METHODS: Nine-year data obtained from 2006 to 2014 by the trace back system at the Division of Human Blood Safety Surveillance of the Korean Centers for Disease Control (KCDC) were reviewed. The suspected cases were assessed according to six categories: (i) related to, (ii) probably related to, (iii) probably not related to, (iv) not related to transfusion, (v) unable to investigate, and (vi) under investigation. RESULTS: Since 2006, 199 suspected serious ATRs were reported in hospitals and medical institutions in Korea, and these ATRs were reassessed by the division of Human Blood Safety Surveillance of the KCDC. Among the reported 193 cases as transfusion related infections, hepatitis C virus (HCV) infection (135, 67.8%) was reported most frequently, followed by hepatitis B virus (HBV) infection (27, 13.6%), HIV infection (13, 6.5%), syphilis (9, 4.5%), malarial infection (4, 2.0%), other bacterial infections (3, 1.5%), HTLV infection (1, 0.5%), and scrub typhus infection (1, 0.5%), respectively. Of the 199 cases, 13 (6.5%) cases were confirmed as transfusion-related (3 HCV infections, 3 malarial infections, 1 HBV infection, 2 Staphylococcus aureus sepsis, 3 transfusion-related acute lung injuries, and 1 hemolytic transfusion reaction). CONCLUSIONS: This is the first nationwide data regarding serious ATRs in Korea and could contribute to the implementation of an effective hemovigilance system.

Blood Safety Management System in Foreign Countries / 대한수혈학회지

In an effort to improve the blood safety management system, Korea Centers for Disease Control and Prevention visited the national agencies and blood centers of foreign countries. In Japan, the management system for Human T-lymphotropic virus positive donors is operated. In Germany, Red Cross Blood Centers provide 75~80% of national blood consumption, and hospital blood centers provided 15~20%. In addition, the Paul Ehrlich Institut is engaged in blood center management and blood product safety, and the Robert Koch Institut manages transfusion-transmitted infection. The standard temperature of RBC transport is 1~10degrees C. In Austria, haemovigilance is operated by the National Blood Authority and adverse reactions following transfusion are investigated by Blood Centers. In Britain, blood is provided by National Health Service Blood and Transplant, and the Serious Hazards of Transfusion, haemovigilance system is operated. Universal leukoreduction has been performed since 1999 in order to prevent transmission of variant Creutzfeldt-Jakob disease.