Treatment challenges persist in advanced lung cancer despite the development of therapies beyond the traditional platinum-based chemotherapy. The early 2000s marked a shift to tyrosine kinase inhibitors targeting epidermal growth factor receptor, ushering in personalized genetic-based treatment. A further significant advance was the development of immune checkpoint inhibitors (ICIs), especially for non–small cell lung cancer. These target programmed death-ligand 1 (PD-L1) and cytotoxic T lymphocyte antigen 4, which enhanced the immune response against tumor cells. However, not all patients respond, and immune-related toxicities arise. This review emphasizes identifying biomarkers for ICI response prediction. While PD-L1 is a widely used, validated biomarker, its predictive accuracy is imperfect. Investigating tumor-infiltrating lymphocytes, tertiary lymphoid structure, and emerging biomarkers such as high endothelial venule, Human leukocyte antigen class I, T-cell immunoreceptors with Ig and ITIM domains, and lymphocyte activation gene-3 counts is promising. Understanding and exploring additional predictive biomarkers for ICI response are crucial for enhancing patient stratification and overall care in lung cancer treatment.

We need to establish an informative guideline to increase inter-institutional and inter-observer reproducibility of renal transplant diagnosis, and to improve the diagnostic ability of pathologists in Korea. A first nation-wide survey for renal transplant pathology was conducted by Renal Pathology Study Group of the Korean Society of Pathologists in 2016, to provide the continued excellence in the transplantation pathology laboratory, and to improve the diagnostic ability for the best treatment of transplant patients. This survey revealed the significant variations in scale, work load and biopsy indications for the renal transplant pathology in various institutions in Korea. The Banff classification were used by all institutions for the diagnosis of renal transplant pathology, but different formats were used: most institutions (70%) used the “2013 Banff classification” while the others were using “2007 Banff classification” (20%) or even older formats. In daily diagnostic practice of the renal allografts, difficulties that pathologists encounter were quite diverse due to different environments they work in. Most respondents agreed that standardized diagnostic practice guidelines, regular education on renal transplant pathology and convenient ways of consultation are further needed. We are currently working toward the enhancement of the expertise of renal pathologists and to increase inter-institutional and inter-observer reproducibility by 1) development of a set of virtual slides of renal allograft biopsies for the training, 2) validation and gathering expert's consensus on the core variables of rejection diagnosis by using virtual slides, and 3) continued education by the developed virtual slide atlas.
Allografts ; Biopsy ; Classification ; Consensus ; Diagnosis ; Education ; Humans ; Kidney ; Korea* ; Pathology* ; Surveys and Questionnaires ; Transplantation

We made a mistake in our recently published article.

Immunoglobulin G4-related disease (IgG4-RD) is a systemic inflammatory disease found in many organs including biliary tract, salivary gland, kidney, and lung. Tubulointerstitial nephritis is the most common renal manifestation, but hematologic involvement of IgG4-RD is rare. Here, we report on a case of a 57-year-old male with IgG4-related interstitial nephritis with bicytopenia, which was initially thought to be systemic lupus erythematosus. He presented with proteinuria, anemia, thrombocytopenia, and low complement levels. Histological findings showed an increased number of IgG4-positive plasma cells (>200/high power field), and an elevated IgG4/IgG ratio (>90%). Serum levels of IgG and IgG4 were also increased. This case emphasized the importance of differential diagnosis of IgG4-RD and immune complex glomerulonephritis.
Anemia ; Antigen-Antibody Complex ; Biliary Tract ; Complement System Proteins ; Diagnosis, Differential ; Glomerulonephritis ; Humans ; Immunoglobulin G ; Immunoglobulins* ; Kidney ; Lung ; Lupus Erythematosus, Systemic ; Male ; Middle Aged ; Nephritis, Interstitial* ; Plasma Cells ; Proteinuria ; Salivary Glands ; Thrombocytopenia

C3 glomerulonephritis (C3GN), a rare condition associated with dysregulation of the alternative pathway of the complement system, is histopathologically characterized by isolated or dominant C3 deposition in the renal glomeruli. We report a case of C3GN associated with anti-complement factor H (CFH) autoantibodies and CHF-related protein deficiency in an adolescent male. A 16-year-old adolescent male was admitted to a hospital with a 1-month history of generalized edema prior to presentation. Persistent microscopic hematuria and low serum C3 levels were incidentally detected at 7 and 10 years of age, respectively. Laboratory test results revealed hypoalbuminemia, nephrotic-range proteinuria, microscopic hematuria, and normal serum creatinine levels. The serum C3 and C4 levels were 17 mg/dL (normal 80–150 mg/dL) and 22 mg/mL (17–40 mg/mL), respectively. Renal biopsy showed typical features of C3GN. Further investigations revealed positive results on plasma anti-CFH autoantibody testing and a homozygous deletion of CFHR1 and CFHR3, which encode CFH-related proteins 1 and 3, respectively. Proteinuria persisted despite treatment with intravenous methylprednisolone, mycophenolate mofetil, and angiotensin-receptor blocker; however, his renal function remained stable. In conclusion, anti-CFH autoantibodies serve as important contributors to C3GN. This is the first case report that describes C3GN in an adolescent Korean male with anti-CFH autoantibodies and homozygous CFHR1 and CFHR3 deletion.

C3 glomerulonephritis (C3GN), a rare condition associated with dysregulation of the alternative pathway of the complement system, is histopathologically characterized by isolated or dominant C3 deposition in the renal glomeruli. We report a case of C3GN associated with anti-complement factor H (CFH) autoantibodies and CHF-related protein deficiency in an adolescent male. A 16-year-old adolescent male was admitted to a hospital with a 1-month history of generalized edema prior to presentation. Persistent microscopic hematuria and low serum C3 levels were incidentally detected at 7 and 10 years of age, respectively. Laboratory test results revealed hypoalbuminemia, nephrotic-range proteinuria, microscopic hematuria, and normal serum creatinine levels. The serum C3 and C4 levels were 17 mg/dL (normal 80–150 mg/dL) and 22 mg/mL (17–40 mg/mL), respectively. Renal biopsy showed typical features of C3GN. Further investigations revealed positive results on plasma anti-CFH autoantibody testing and a homozygous deletion of CFHR1 and CFHR3, which encode CFH-related proteins 1 and 3, respectively. Proteinuria persisted despite treatment with intravenous methylprednisolone, mycophenolate mofetil, and angiotensin-receptor blocker; however, his renal function remained stable. In conclusion, anti-CFH autoantibodies serve as important contributors to C3GN. This is the first case report that describes C3GN in an adolescent Korean male with anti-CFH autoantibodies and homozygous CFHR1 and CFHR3 deletion.

Choristoma, also known as a hairy polyp, is a rare benign mass that commonly occurs in the nasopharynx and oropharynx in the head and neck region. It is usually diagnosed in children and has rarely been reported in adults. In this study, we describe a nasopharyngeal choristoma in an adult man. The mass was located at the lateral nasopharyngeal wall, and the patient expressed intermittent nasal stuffiness and ear fullness. The mass was successfully removed using an endoscopic approach. Since nasopharyngeal choristoma in adults is rare, it is important to distinguish it from other benign tumors located in the nasopharynx or nasal cavity. In this report, we describe the radiologic characteristics of nasopharyngeal choristoma and summarize the importance of differential diagnosis from other benign masses.

Background: Squamous cell carcinomas (SqCCs) of the lung are known to arise more often in a central area but reports of peripheral SqCCs have increased, with a pathogenesis that is obscured. In this study, the clinicopathologic characteristics of peripheral lung SqCCs were studied and compared with those of the central type. Methods: This study included 63 peripheral lung SqCCs and 48 randomly selected central cases; hematoxylin and eosin-stained slides of surgically resected specimens were reviewed in conjunction with radiologic images and clinical history. Cytokeratin-7 immunohistochemical staining of key slides and epidermal growth factor receptor (EGFR)/KRAS mutations tested by DNA sequencing were also included. Results: Stages of peripheral SqCCs were significantly lower than central SqCCs (p=.016). Cystic change of the mass (p=.007), presence of interstitial fibrosis (p=0.007), and anthracosis (p=.049) in the background lung were significantly associated with the peripheral type. Cytokeratin-7 positivity was also higher in peripheral SqCCs with cutoffs of both 10% and 50% (p=.011). Pathogenic mutations in EGFR and KRAS were observed in only one case out of the 72 evaluated. The Cox proportional hazard model indicated a significantly better disease-free survival (p=.009) and the tendency of better overall survival (p=.106) in the peripheral type. Conclusions In peripheral type, lower stage is a favorable factor for survival but more frequent interstitial fibrosis and older age are unfavorable factors. Multivariate Cox analysis revealed that peripheral type is associated with better disease-free survival. The pathogenesis of peripheral lung SqCCs needs further investigation, together with consideration of the background lung conditions.

BACKGROUND: The tall cell variant of papillary thyroid carcinoma (TCVPTC) is more aggressive than classic papillary thyroid carcinoma (PTC), but the percentage of tall cells needed to diagnose TCVPTC remains controversial. In addition, little is known about the clinicopathologic features of classic PTC with tall cell features (TCF). METHODS: We retrospectively selected and reviewed the clinicopathologic features and presence of the BRAF mutation in 203 cases of classic PTC, 149 cases of classic PTC with TCF, and 95 cases of TCVPTCs, which were defined as PTCs having <10%, 10-50%, and > or =50% tall cells, respectively. RESULTS: TCVPTCs and classic PTCs with TCF did not vary significantly in clinicopathologic characteristics such as pathologic (p) T stage, extrathyroidal extension, pN stage, lateral lymph node metastasis, or BRAF mutations; however, these features differed significantly in TCVPTCs and classic PTCs with TCF in comparison to classic PTCs. Similar results were obtained in a subanalysis of patients with microcarcinomas (< or =1.0 cm in size). CONCLUSIONS: Classic PTCs with TCF showed a similar BRAF mutation rate and clinicopathologic features to TCVPTCs, but more aggressive characteristics than classic PTCs.
Classification ; Humans ; Lymph Nodes ; Mutation Rate ; Neoplasm Metastasis ; Retrospective Studies ; Thyroid Neoplasms*

The most common BRAF mutation in thyroid cancer is c.1799T>A (p.Val600Glu), and other BRAF mutations are rarely reported. We investigated the clinicopathological features of thyroid cancer with rare BRAF mutations. A total of 2,763 patients with thyroid cancer underwent molecular testing by direct DNA sequencing for mutations in BRAF exon 15. Among them, 2,110 (76.4%) had BRAF mutations. The c.1799T>A mutation was found in 2,093 (76.9%) of 2,722 papillary carcinomas and in one of 7 medullary carcinomas. Sixteen cases (0.76%) harbored rare mutation types. Five cases had single-nucleotide substitutions, 5 cases had small in-frame deletion or insertion, and one harbored a two-nucleotide substitution. Of these mutations, 2 were novel (c.1797_1798insGAGACTACA, c.[1799T>A; 1801_1812del]). The c.1801A>C mutation was identified in 4 follicular variant papillary carcinomas and one follicular carcinoma. None of the patients with the c.1801A>C mutation showed extrathyroidal extension or lymph node metastasis. The prevalence of rare BRAF mutations was 0.76% of all BRAF-positive thyroid cancers, and the rare mutations were associated with less aggressive pathologic features. Although BRAF mutations are detected exclusively in papillary carcinoma, they are also found in medullary carcinoma and follicular carcinoma.
Base Sequence ; Female ; Genetic Markers/genetics ; Genetic Predisposition to Disease/epidemiology/*genetics ; Humans ; Incidence ; Male ; Middle Aged ; Molecular Sequence Data ; Mutation/genetics ; Polymorphism, Single Nucleotide/genetics ; Prevalence ; Proto-Oncogene Proteins B-raf/*genetics ; Rare Diseases/epidemiology/genetics ; Republic of Korea/epidemiology ; Risk Factors ; Thyroid Neoplasms/epidemiology/*genetics/*pathology ; Tumor Markers, Biological/*genetics