A Deep Learning-Based Assay for Programmed Death Ligand 1 Immunohistochemistry Scoring in Non-Small Cell Lung Carcinoma: Does it Help Pathologists Score?

Several studies have developed various artificial intelligence (AI) models for immunohistochemical analysis of programmed death ligand 1 (PD-L1) in patients with non-small cell lung carcinoma; however, none have focused on specific ways by which AI-assisted systems could help pathologists determine the tumor proportion score (TPS). In this study, we developed an AI model to calculate the TPS of the PD-L1 22C3 assay and evaluated whether and how this AI-assisted system could help pathologists determine the TPS and analyze how AI-assisted systems could affect pathologists' assessment accuracy. We assessed the 4 methods of the AI-assisted system: (1 and 2) pathologists first assessed and then referred to automated AI scoring results (1, positive tumor cell percentage; 2, positive tumor cell percentage and visualized overlay image) for final confirmation, and (3 and 4) pathologists referred to the automated AI scoring results (3, positive tumor cell percentage; 4, positive tumor cell percentage and visualized overlay image) while determining TPS. Mixed-model analysis was used to calculate the odds ratios (ORs) with 95% CI for AI-assisted TPS methods 1 to 4 compared with pathologists' scoring. For all 584 samples of the tissue microarray, the OR for AI-assisted TPS methods 1 to 4 was 0.94 to 1.07 and not statistically significant. Of them, we found 332 discordant cases, on which the pathologists' judgments were inconsistent; the ORs for AI-assisted TPS methods 1, 2, 3, and 4 were 1.28 (1.06-1.54; P = .012), 1.29 (1.06-1.55; P = .010), 1.28 (1.06-1.54; P = .012), and 1.29 (1.06-1.55; P = .010), respectively, which were statistically significant. For discordant cases, the OR for each AI-assisted TPS method compared with the others was 0.99 to 1.01 and not statistically significant. This study emphasized the usefulness of the AI-assisted system for cases in which pathologists had difficulty determining the PD-L1 TPS.

Comprehensive analyses of the clinicopathological features and genomic mutations of combined hepatocellular-cholangiocarcinoma.

AIM: Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is a rare primary liver cancer that has two different tumor phenotypes in a single tumor nodule. The relationship between genetic mutations and clinicopathological features of cHCC-CCA remains to be elucidated. METHODS: Whole-exome sequencing analyses were carried out in 13 primary and 2 recurrent cHCC-CCAs. The whole-exome analyses and clinicopathological information were integrated. RESULTS: TP53 was the most frequently mutated gene in this cohort, followed by BAP1, IDH1/2, and NFE2L2 mutations in multiple cases. All tumors with diameters <3 cm had TP53 mutations. In contrast, six of seven tumors with diameters ≥3 cm did not have TP53 mutations, but all seven tumors had mutations in genes associated with various pathways, including Wnt, RAS/PI3K, and epigenetic modulators. In the signature analysis, the pattern of mutations shown in the TP53 mutation group tended to be more similar to HCC than the TP53 nonmutation group. Mutations in recurrent cHCC-CCA tumors were frequently identical to those in the primary tumor, suggesting that those tumors originated from identical clones of the primary cHCC-CCA tumors. Recurrent and co-occurrent HCC tumors in the same patients with cHCC-CCA had either common or different mutation patterns from the primary cHCC-CCA tumors in each case. CONCLUSIONS: The study suggested that there were two subtypes of cHCC-CCA, one involving TP53 mutations in the early stage of the carcinogenic process and the other not involving such mutations. The comparison of the variants between primary and recurrent tumors suggested that cHCC-CCA was derived from an identical clone.

High-grade salivary gland carcinoma with the ETV6-NTRK3 gene fusion: A case report and literature review of secretory carcinoma with high-grade transformation.

Secretory carcinoma or mammary analog secretory carcinoma is an entity of salivary gland carcinoma that is characterized by the ETV6-NTRK3 gene fusion. Although it is generally considered to be a low-grade malignancy, some cases of secretory carcinoma with high-grade transformation (SCHG) have been reported. We herein describe a case of SCHG composed almost exclusively of the high-grade component. The patient presented with a growing mass in the buccal mucosa and underwent surgery. Tumor cells showing high-grade nuclear atypia were arranged in solid or cribriform nests with comedo-like necrosis. A differential diagnosis included high-grade salivary gland carcinoma, such as salivary duct carcinoma. Immunohistochemically, tumor cells were focally positive for S-100 and negative for mammaglobin and showed nuclear positivity for pan-Trk. A reverse transcription polymerase chain reaction assay showed that the tumor harbored the ETV6-NTRK3 gene fusion. A histological review of microscopic slides of the tumor did not reveal a typical secretory carcinoma component, except for a very focal area. We ultimately diagnosed this tumor as SCHG. This case underscores the importance of recognizing the histological spectrum of SCHG and the utility of pan-Trk immunohistochemistry to detect secretory carcinoma, which may be targeted by tyrosine kinase inhibitors.

[A Case of Rapidly Growing Sarcomatoid Urothelial Carcinoma of the Renal Pelvis and Ureter].

75 year-old man followed up regularly for the treatment of lung cancer came to our hospital with a chief complaint of general malaise. Blood test results showed deterioration in the renal function, and computed tomography (CT) confirmed left hydronephrosis. He was admitted to the hospital with the diagnosis of obstructive pyelonephritis. Despite antibiotic therapy after the left ureteral stent placement, CT on day 19 of hospitalization showed an enlarged soft tissue shadow along the renal pelvis and ureter, which was suspected to be peripelvic urinary extravasation caused by stent occlusion. We decided that conservative treatment would not improve his condition and conducted surgical therapy considering the possibility of malignancy. Intraoperatively, viscous and fragile tumor affected the renal pelvis and ureter. The operation resulted in left nephrectomy because radical resection was impossible. The pathological diagnosis was sarcomatoid urothelial carcinoma of the renal pelvis with ureter origin. He died due to multipleorgan failureon day 20 after theope ration. Were port a caseof sarcomatoid urothelial carcinoma in the upper urinary tract that was difficult to diagnose preoperatively based on imaging studies.

Discohesive growth pattern (Disco-p) as an unfavorable prognostic factor in lung adenocarcinoma: an analysis of 1062 Japanese patients with resected lung adenocarcinoma.

Discohesive growth pattern (Disco-p) is often observed in lung adenocarcinoma (ADC) and mimics tumor budding (TB), stromal invasive-type micropapillary pattern (SMPP), and complex glandular pattern. However, the clinical impact of Disco-p in lung ADC has not been well studied. To investigate the prognostic significance of Disco-p, we analyzed 1062 Japanese patients with resected lung ADC. Disco-p was defined as an invasive growth pattern composed of single tumor cells, or trabeculae or small nests of tumor cells associated with desmoplastic fibrous stroma. We recorded the percentage of Disco-p in 5% increments independent of the major histologic pattern and investigated its correlation with different clinicopathological factors. We also analyzed the overall survival (OS) and disease-free survival (DFS). Disco-p was observed in 203 tumors (19.1%). Disco-p was significantly associated with male sex, smoking, lymph node metastasis, large tumor size, high TNM stage, lymphovascular and pleural invasion, spread through air spaces, and TB (all, p < 0.001). Of the total cases, only eight cases exhibited a dubious pattern between SMPP and Disco-p. Disco-p was also associated with wild-type EGFR (p < 0.001) and ALK fusion (p = 0.008). Patients harboring tumors with Disco-p had significantly worse prognoses (OS and DFS (both, p < 0.001)) compared with those without Disco-p. On multivariate analysis, Disco-p was an independent prognostic factor of worse OS (hazard ratio (HR), 2.572; 95% confidence interval (CI), 1.789-3.680; p < 0.001), and DFS (HR, 3.413; 95% CI, 2.482-4.683; p < 0.001), whereas TB was not an independent unfavorable prognostic factor. Disco-p was an independent unfavorable prognostic factor in patients with resected lung ADC, although a careful evaluation is necessary to distinguish it from similar patterns. We proposed that Disco-p should be recognized as a new invasive pattern and accurately recorded for the better management of patients with lung ADCs.

Temozolomide and etoposide combination for the treatment of relapsed osteosarcoma.

The prognosis of patients with relapsed osteosarcoma is extremely poor and the optimal treatment remains to be identified. Here, we retrospectively analysed the clinical outcomes of nine patients with relapsed osteosarcoma treated with temozolomide/etoposide. Of the two patients who received temozolomide/etoposide as palliative therapy for unresectable tumours, one remained alive with stable disease for >4 years. The remaining seven patients received temozolomide/etoposide as adjuvant therapy following resection of relapsed metastatic disease; of these, one was free from disease for 41 months. Potentially beneficial effects were observed in two of three O6-methylguanine-DNA methyltransferase protein-negative patients, whereas all five O6-methylguanine-DNA methyltransferase-positive patients experienced subsequent relapse. None of the patients experienced severe adverse effects requiring hospitalization. Temozolomide/etoposide is a feasible candidate as salvage therapy for relapsed osteosarcoma. Further studies are needed to verify the utility of O6-methylguanine-DNA methyltransferase protein expression as a biomarker for predicting the response to this treatment.

Clinicopathological features and recurrence patterns of combined hepatocellular-cholangiocarcinoma.

BACKGROUND: Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is a primary liver carcinoma with both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) components. We examined the clinicopathological characteristics and recurrence patterns of cHCC-CCA. Because of the rarity of cHCC-CCA, its etiology, clinicopathological features, and prognosis in comparison with other primary liver carcinoma remain unknown. Its recurrence pattern and sites in particular also need to be elucidated. METHODS: All patients who underwent hepatectomy for primary liver malignancies between 2005 and 2015 were retrospectively included in this study. RESULTS: Eight hundred and ninety-four hepatectomies were performed. Nineteen cases of cHCC-CCA (2.1%) in 16 patients were enrolled. Three patients underwent re-hepatectomy. The background of hepatitis viruses and tumor marker patterns of cHCC-CCA were similar to those of HCC and dissimilar to those of intrahepatic CCA (iCCA). Biliary invasion was common in cHCC-CCA and iCCA. The 5-year overall survival values of the cHCC-CCA, HCC, and iCCA patients were 44.7%, 56.6%, and 38.5%, respectively. The 5-year recurrence-free survival values of the cHCC-CCA, HCC, and iCCA patients were 12.2%, 28.7%, and 32.9%, respectively. The liver was the most common recurrence site. Unlike HCC, however, the lymph node was the second-most common recurrence site in both cHCC-CCA and iCCA. Pathological samples of the recurrent lesions were obtained in six patients, and four had cHCC-CCA recurrence pathologically. CONCLUSION: cHCC-CCA had a mixture of characteristics of HCC and iCCA. Many cases of cHCC-CCA remained cHCC-CCA pathologically even after recurrence.

GATA6-positive lung adenocarcinomas are associated with invasive mucinous adenocarcinoma morphology, hepatocyte nuclear factor 4α expression, and KRAS mutations.

AIMS: GATA6 is known to play a role in lung development. However, its role in the carcinogenesis of lung cancer is not well studied. The aim of this study was to analyse GATA6 expression in lung adenocarcinomas (LAs) by immunohistochemistry (IHC) in order to define its association with clinicopathological characteristics. METHODS AND RESULTS: IHC analysis of GATA6 was performed with tissue microarray slides containing 348 LAs. The association between GATA6 expression and clinicopathological parameters was evaluated. GATA6 expression in epithelial tumours other than lung cancer was also evaluated. GATA6 expression was found in 47 LAs (13.5%). This occurred more frequently in younger patients (P = 0.005), and was associated with the absence of lymph node metastasis (P =0.024), well-differentiated to moderately differentiated tumours (P < 0.001), the absence of lymphatic invasion (P = 0.020), and the absence of vascular invasion (P = 0.011). GATA6 expression was associated with mucin production (P < 0.001), the invasive mucinous adenocarcinoma subtype (P < 0.001), KRAS mutations (P = 0.026), expression of MUC2 (P < 0.001), CDX2 (P = 0.049), and MUC5AC (P < 0.001), and absence of expression of TTF-1 (P = 0.002). GATA6 expression was also associated with hepatocyte nuclear factor 4α (HNF4α) expression (P < 0.001). GATA6 expression tended to indicate better prognoses, whereas patients with HNF4α expression had significantly worse prognoses (P = 0.033). Of 270 tumours other than lung cancer, 110 expressed GATA6. CONCLUSIONS: These findings suggest that GATA6 might interact with HNF4α and contribute to the development of mucinous-type LAs.

Adipophilin expression in lung adenocarcinoma is associated with apocrine-like features and poor clinical prognosis: an immunohistochemical study of 328 cases.

AIMS: The lipogenic pathway is up-regulated in proliferating cells. However, the clinical impact of neoplastic steatogenesis in lung cancer is unclear. The aim of the present study was to evaluate the association of intracytoplasmic lipids with the clinicopathological features of lung adenocarcinoma (ADC), by immunohistochemical analysis of adipophilin (ADP), a coating protein found on intracytoplasmic lipid droplets. METHODS AND RESULTS: Tissue microarrays consisting of 328 primary lung ADCs surgically resected at Kyoto University Hospital were immunostained for ADP. Subsequently, correlations between ADP expression and clinical, molecular and survival data were performed. Fifty-one (15.5%) cases were ADP-positive. The presence of vascular invasion (P = 0.003), predominantly solid histology (P < 0.001), poorly differentiated type (P < 0.001), wild-type EGFR (P = 0.002), ALK fusion (P < 0.001), strong/diffuse mitochondrial staining (P < 0.001), a lack of surfactant protein B expression (P = 0.014) and a high Ki67 index (P < 0.001) were significantly correlated with ADP-positive ADC. In contrast, there were no correlations between ADP-positive ADC and sex, age, smoking history, tumour stage, thyroid transcription factor-1 expression, or KRAS mutational status. ADP-positive ADCs had apocrine-like features (P < 0.001). Patients with ADP-positive ADC had worse disease-free and overall survival (P = 0.047 and P = 0.013, respectively) than those with ADP-negative ADC. CONCLUSIONS: ADP was expressed in a small proportion of lung ADCs. ADP-positive lung ADC was significantly associated with apocrine-like features, wild-type EGFR, and poor prognosis, suggesting that ADP-positive lung ADC could be a distinct subtype of lung adenocarcinoma, induced by up-regulation of the lipogenic pathway.

Evaluating the effectiveness of RNA in-situ hybridization for detecting lung adenocarcinoma with anaplastic lymphoma kinase rearrangement.

AIMS: An easy and rapid assay for detecting mRNA in formalin-fixed paraffin-embedded samples [RNA in-situ hybridization (ISH)] has been reported recently. The aim of this study was to investigate the diagnostic accuracy of RNA ISH in detecting lung adenocarcinoma (LA) with anaplastic lymphoma kinase (ALK) gene rearrangement. METHODS AND RESULTS: We tested ALK RNA ISH on 11 resected LAs for which ALK fusion was confirmed by immunohistochemistry (IHC) and/or fluorescence in-situ hybridization (FISH). ALK mRNA expression was detected by RNA ISH in all 11 ALK-positive LAs, with a mean positive cell proportion of 68.4% (median, 75.3%; range, 3-98.8%), by counting 100 tumour cells at 10 different loci; RNA ISH did not detect ALK mRNA expression in the normal surrounding lung cells. Next, we explored the concordance between ALK RNA ISH and IHC/FISH tests by using tissue microarrays (TMAs) containing 294 LAs. In the TMA slides, we found five ALK-positive cases with IHC and/or FISH. The mean proportion of ALK RNA ISH-positive cells in these five cases was 75.6% (median, 82%; range, 40-94%), whereas the proportion of ALK RNA ISH-positive cells in the remaining 289 cases was 0.3% (median 0%; range, 0-15%). When the cutoff value was set at 15%, ALK RNA ISH-positive and ALK RNA ISH-negative cases were distinguishable with 100% sensitivity and specificity relative to the IHC/FISH tests. CONCLUSIONS: Our findings show that RNA ISH is useful for detecting ALK rearrangement with high sensitivity and specificity relative to conventional IHC/FISH tests. Thus, RNA ISH, which is an easy and rapid assay, could be an alternative method to IHC and FISH.

Multicystic biliary hamartoma with extremely elevated CA19-9: a case report.

Multicystic biliary hamartoma (MCBH) is a rare cystic disease of the liver. We herein report a case of MCBH associated with extremely elevated levels of serum carbohydrate antigen (CA) 19-9. A 53-year-old man was referred to our hospital because of extremely elevated CA19-9 levels (more than 12,000 U/mL). Enhanced abdominal computed tomography and magnetic resonance imaging (MRI) revealed a multicystic tumor with a calcified wall in the left lobe of the liver, although no apparent intracystic nodule was detected. Because of the possibility of a malignant tumor, such as intraductal papillary neoplasm of the bile duct or cystadenocarcinoma, the patient underwent left hepatectomy. Based on the postoperative pathological findings, the lesion was diagnosed as MCBH. The serum CA19-9 level drastically decreased after surgery. We encountered a rare case of MCBH with extremely elevated CA19-9 levels.

Visceral disseminated varicella zoster virus infection after rituximab treatment for granulomatosis with polyangiitis.

We report on a 30-year-old Japanese woman with granulomatosis with polyangiitis (GPA) complicated by pituitary diabetes insipidus and multiple lung granulomas. The granulomas disappeared with prednisolone (50 mg/day) and rituximab, although continuous nasal desmopressin was needed to control diabetes insipidus after immunosuppressive therapies. At the time of presentation, the patient had abdominal pain and disseminated intravascular coagulation but no rash. She died of continuous hemorrhage from her skin of neck, mucosa of her pharynx, and small intestine. At autopsy, varicella zoster virus (VZV)-DNA detected in serum and VZV antigens detected in tissues of her pharynx, esophagus, and liver led to a diagnosis of visceral disseminated VZV infection (VD-VZV). She also complicated cytomegalovirus infection in her stomach and ovaries. Her posterior pituitary gland had been replaced by foamy macrophages. In 38 reported cases of VD-VZV, rash appeared following the onset of abdominal pain (mean interval, 6.5 days) but was lacking in 11% of cases. The mortality rate associated with VD-VZV was as high as 29% and survived cases were treated with antivirals earlier than mortal cases. A quick diagnosis with detection of VZV-DNA or VZV antigens in sera or tissues using PCR or immunohistochemistry examination and early empirical treatment with antivirals are important.

A case of sclerosing angiomatoid nodular transformation:the correlation between imaging and pathological findings.

A 53-year-old woman was referred to our hospital with a 40-mm splenic tumor, which was detected incidentally on abdominal computed tomography during hospitalization for pyelonephritis. The tumor was hypointense on T2-weighted imaging and gradually enhanced on dynamic study. The tumor increased in size over a six-month period. Since we could not exclude splenic malignancy, we performed laparoscopic partial splenectomy. Histological examination revealed multiple angiomatoid nodules with three distinct vessel types. Pathologically, the tumor was diagnosed as a sclerosing angiomatoid nodular transformation (SANT). We then examined the correlation between the imaging and pathological findings, and performed a review of previous reports, concluding that contrast-enhanced MRI was the most useful modality for diagnosing SANT.

Decreased expression of lysophosphatidylcholine (16:0/OH) in high resolution imaging mass spectrometry independently predicts biochemical recurrence after surgical treatment for prostate cancer.

BACKGROUND: Human prostate cancers are highly heterogeneous, indicating a need for various novel biomarkers to predict their prognosis. Lipid metabolism affects numerous cellular processes, including cell growth, proliferation, differentiation, and motility. Direct profiling of lipids in tissue using high-resolution matrix-assisted laser desorption/ionization imaging mass spectrometry (HR-MALDI-IMS) may provide molecular details that supplement tissue morphology. METHODS: Prostate tissue samples were obtained from 31 patients, with localized prostate cancer who underwent radical prostatectomy. The samples were assessed by HR-MALDI-IMS in positive mode, with the molecules identified by tandem mass spectrometry (MS/MS). The effect of identified molecules on prostate specific antigen recurrence free survival after radical prostatectomy was determined by Cox regression analysis and by the Kaplan-Meier method. RESULTS: Thirteen molecules were found to be highly expressed in prostate tissue, with five being significantly lower in cancer tissue than in benign epithelium. MS/MS showed that these molecules were [lysophosphatidylcholine (LPC)(16:0/OH)+H](+), [LPC(16:0/OH)+Na](+), [LPC(16:0/OH)+K](+), [LPC(16:0/OH)+matrix+H](+), and [sphingomyelin (SM)(d18:1/16:0)+H](+). Reduced expression of LPC(16:0/OH) in cancer tissue was an independent predictor of biochemical recurrence after radical prostatectomy. CONCLUSIONS: HR-MALDI-IMS showed that the expression of LPC(16:0/OH) and SM(d18:1/16:0) was lower in prostate cancer than in benign prostate epithelium. These differences in expression of phospholipids may predict prostate cancer aggressiveness, and provide new insights into lipid metabolism in prostate cancer.

CD8⁺ tumor-infiltrating lymphocytes at primary sites as a possible prognostic factor of cutaneous angiosarcoma.

Tumor-infiltrating lymphocytes (TILs) have been reported as a prognostic factor in various cancers and are a promising target for immunotherapy. To investigate whether TILs have any impact on the prognosis of angiosarcoma patients, 55 non-treated patients (40 patients at stage 1 with cutaneous localized tumors, 4 patients at stage 2 with lymph node metastases and 11 patients at stage 3 with distant metastases) with angiosarcoma were evaluated retrospectively by immunohistochemistry stained CD4, CD8, FOXP3 and Ki67. The Kaplan-Meier method was used to estimate overall survival with patients at stage 1. Survival differences were analyzed by the log-rank test. Patients with higher numbers of CD8(+) TILs in their primary tumors survived significantly longer compared with patients with lower values. Moreover, the number of CD8 in TILs was positively correlated with a distant metastasis-free period. The total number of primary TILs (CD4 plus CD8) and CD8(+) primary TILs of stage 3 patients with distant metastases was positively correlated with their overall survival. To evaluate whether CD8(+) effector T cells are activated or differentiated, flow cytometric analysis of peripheral blood mononuclear cells (PBMC) was performed. The percentages of CD8(+) T cells producing IFN-γ in PBMC were significantly higher in patients with angiosarcoma (n = 10) compared not only with that of healthy controls (n = 20) but also patients with advanced melanoma (n = 11). These results suggest that anti-tumor immunity is clinically relevant in angiosarcoma.

Application of complement component 4d immunohistochemistry to ABO-compatible and ABO-incompatible liver transplantation.

Antibody-mediated rejection (AMR) is difficult to diagnose after ABO-compatible or ABO-identical (ABO-C) liver transplantation. To determine whether complement component 4d (C4d) immunostaining would be useful for diagnosing AMR, we compared the results of C4d immunohistochemistry for allograft biopsy samples with assays for anti-donor antibodies performed at the time of biopsy. One hundred fourteen patients with ABO-C grafts and 29 patients with ABO-incompatible (ABO-I) grafts were included. Linear C4d endothelial staining (identifiable with a 4× objective lens) or staining seen in 50% or more of the portal tracts was considered positive. Five of the 114 patients (4%) with ABO-C grafts and 15 of the 29 patients (52%) with ABO-I grafts showed C4d positivity. In the ABO-C cases, C4d positivity in late biopsy samples (≥30 days after transplantation) was associated with stage 2 or higher fibrosis (METAVIR score; P = 0.01) and with the presence of donor-specific anti-human leukocyte antigen DR antibodies (HLA-DR DSAs) with a mean fluorescence intensity > 5000 according to the Luminex single-antigen bead assay (P = 0.04). Conversely, the presence of HLA-DR DSAs was associated with the presence of stage 2 or higher fibrosis, acute cellular rejection, and C4d positivity. During the 2-year follow-up, neither C4d positivity nor HLA-DR DSAs were related to graft loss. Among ABO-I patients, C4d positivity was not associated with allograft dysfunction or fibrosis. Only 3 of the 15 C4d-positive patients (20%) showed periportal hemorrhagic edema, which could be a histological sign of AMR in ABO-I grafts, and they were the only cases associated with elevations in anti-donor A/B antibody titers. In conclusion, C4d endothelial positivity among ABO-C patients is an uncommon event that could be associated with chronic graft damage with or without clinical AMR. C4d positivity is common among ABO-I patients and may not be associated with allograft dysfunction if alloantibody titers are not elevated.

[A case of successful living related renal transplantation in a patient with end-stage renal disease resulting from sarcoidosis].

We report a case in a 44-year-old man with known past history of sarcoidosis associated with uveitis that was first diagnosed when he was 20 years old. He developed renal dysfunction 6 years after the diagnosis of sarcoidosis. At that time, a renal biopsy revealed non-necrotizing granulomatous interstitial nephritis, typical findings of renal involvement of sarcoidosis. Despite corticosteroid therapy administered soon after the biopsy, the renal dysfunction gradually progressed to end-stage renal disease. The patient underwent kidney transplantation from a living donor and the renal graft has been functioning well with no evidence of recurrence 10 months postoperatively, and with a serum creatinine level between 1.2 and 1.5 mg/dl.

Histopathological significance of connective tissue disease-associated interstitial lung disease in transbronchial lung cryobiopsy specimens.

Differentiating between idiopathic interstitial pneumonia (IIP) and secondary interstitial pneumonia, particularly connective tissue disease-associated interstitial lung disease (CTD-ILD), can be challenging histopathologically, and there may be discrepancies among pathologists. While surgical lung biopsy has traditionally been considered the gold standard for diagnosing interstitial pneumonia, the usefulness of transbronchial lung cryobiopsy (TBLC) has been reported. If TBLC could effectively distinguish between primary and secondary diseases, it would provide a less invasive option for patients. The aim of this study was to identify specific pathologic findings in TBLC specimens that could assist in distinguishing CTD-ILD from IIP. A total of 93 underwent TBLC at Tenri Hospital between 2018 and 2022. We retrospectively reviewed cases of CTD-ILD exhibiting a nonspecific interstitial pneumonia (NSIP) pattern (CTD-NSIP) and cases of NSIP with an unknown etiology (NSIP-UE), as determined through multidisciplinary discussion. Nineteen patients with CTD-NSIP and 26 patients with NSIP-UE were included in the study for clinicopathological analysis. The CTD-NSIP group had a significantly higher proportion of female patients compared to the NSIP-UE group (79% vs. 31%; p = 0.002). The presence of both fresh and old intraluminal fibrosis within the same TBLC specimen was significantly more frequent in CTD-NSIP group than in the NSIP-UE group (p = 0.023). The presence of an NSIP pattern with co-existing fresh and old intraluminal fibrosis in TBLC specimens raised suspicion for CTD-ILD.