Pulmonary Epstein-Barr virus-associated smooth muscle tumor after kidney transplantation: two case reports with review of differential diagnosis.

Pulmonary nodules are a common complication in solid organ transplant recipients, and may have various underlying causes, with Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) being one of them. Given the rarity of this entity, we describe the diagnosis and therapeutic interventions for post-transplant EBV-SMT in two individuals. Both cases involved female patients who were diagnosed with multiple pulmonary nodules 60 months and 116 months, respectively, after receiving living-related kidney transplantation. Pathological examination revealed a spindle cell tumor, with immunophenotype and EBV in situ hybridization supporting the diagnosis of EBV-SMT. After diagnosis, these two patients underwent intervention by decreasing their intake of immunosuppressants. As of the latest follow-up, the patients' lesion size remained stable, and their overall condition was favorable. We also reviewed literature about the morphological and molecular pathological features of EBV-SMT and highlighted the diagnosis and differential diagnosis of pulmonary spindle cell lesions especially in the setting of immunosuppression.

Expert Consensus on Pathological Diagnosis of Intrahepatic Cholangiocarcinoma (2022 version).

Intrahepatic cholangiocarcinoma (iCCA) can originate from the large bile duct group (segment bile ducts and area bile ducts), small bile duct group (septal bile ducts and interlobular bile ducts), and terminal bile duct group (bile ductules and canals of Hering) of the intrahepatic biliary tree, which can be histopathological corresponding to large duct type iCCA, small duct type iCCA and iCCA with ductal plate malformation pattern, and cholangiolocarcinoma, respectively. The challenge in pathological diagnosis of above subtypes of iCCA falls in the distinction of cellular morphologies, tissue structures, growth patterns, invasive behaviors, immunophenotypes, molecular mutations, and surgical prognoses. For these reasons, this expert consensus provides nine recommendations as a reference for standardizing and refining the diagnosis of pathological subtypes of iCCA, mainly based on the 5th edition of the World Health Organization Classification of Tumours of the Digestive System.

A standardized pathological proposal for evaluating microvascular invasion of hepatocellular carcinoma: a multicenter study by LCPGC.

BACKGROUND AND AIMS: Microvascular invasion (MVI) is a key pathological factor that severely affects the postoperative prognosis of patients with hepatocellular carcinoma (HCC). However, no MVI classification schemes based on standardized gross sampling protocols of HCC are available at present. METHODS: 119 HCC specimens were sampled at multiple sites (3-, 7-, and 13 points) for the optimum MVI detection rate. 16,144 resected HCCs were graded as M0, M1 or M2 by adopting three-tiered MVI grading (MVI-TTG) scheme based on the seven-point sampling protocol (SPSP). Survival analyses were performed on 2573 patients to explore the advantages of MVI-TTG. RESULTS: The MVI detection rate determined by SPSP was significantly higher than that determined by the 3-point sampling method (34.5% vs. 47.1%, p = 0.048), but was similar to that determined by the 13-point sampling method (47.1% vs. 51.3%, p = 0.517). Among 16,144 resected HCCs, the proportions of M0, M1 and M2 specimens according to SPSP were 53.4%, 26.2% and 20.4%, respectively. Postoperative survival analysis in 2573 HCC patients showed that the 3-year recurrence rates in M0, M1 and M2 MVI groups were 62.5%, 71.6% and 86.1%, respectively (p < 0.001), and the corresponding 3-year overall survival (OS) rates were 94.1%, 87.5% and 67.0%, respectively (p < 0.001). M1 grade was associated with early recurrence, while M2 grade was associated with both early and late recurrence. MVI-TTG had a larger area under the curve and net benefit rate than the two-tiered MVI grading scheme for predicting time to recurrence and OS. CONCLUSIONS: SPSP is a practical method to balance the efficacy of sampling numbers and MVI detection rates. MVI-TTG based on SPSP is a better prognostic predictor than the two-tiered MVI scheme. The combined use of SPSP and MVI-TTG is recommended for the routine pathological diagnosis of HCC.

Thyroid-Like Intrahepatic Cholangiocarcinoma: Report of a Case and Review of the Literature.

Intrahepatic cholangiocarcinoma is a relatively uncommon malignant neoplasm. We recently encountered an unusual case of intrahepatic cholangiocarcinoma that histologically resembled a thyroid carcinoma. A thorough review of the English literature revealed only 2 similar cases that have been previously reported. Immunohistochemical studies are imperative to confirm the diagnosis of cholangiocarcinoma and to exclude the possibility of metastatic thyroid carcinoma and other malignancies with thyroid-like features.

The continual presence of C3d but not IgG glomerular capillary deposition in stage I idiopathic membranous nephropathy in patients receiving corticosteroid treatment.

BACKGROUND: Pathologic diagnosis of stage I idiopathic membranous nephropathy (MN-I) requires electron microscopy or immunohistochemistry that shows a glomerular capillary staining pattern of IgG and C3. However, it is not uncommon that renal biopsy did not obtain sufficient material for electron microscopy and that IgG and C3 staining in glomeruli largely lost at biopsy due to corticosteroid treatment. Since C3d is one of the final degradation products of C3 that is more stable in vivo, we determine if C3d staining could be used as a novel immunohistochemical marker for MN-I. METHODS AND RESULTS: 74 MN-I patients with electron microscopy proven MN-I were examined by immunoperoxidase staining of C3d. Intensive C3d staining was present in glomerular capillary like the staining pattern of IgG and C3 in MN-I. Importantly, in 40 MN-I patients who underwent corticosteroid treatment at biopsy the intensity and glomerular capillary pattern of C3d staining remained largely intact while the staining for IgG had substantially reduced and the pattern of glomerular capillary staining became unrecognizable. CONCLUSIONS: C3d glomerular capillary staining may be a novel marker for pathologic diagnosis of MN-I that is continuously present at biopsy in patient who has received corticosteroid treatment. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2120780075734479.

[An experimental study on the safety of intratracheal drug administration].

OBJECTIVE: To explore whether injury and repair occur in the trachea and the lung after intra-tracheal administration of different drugs. METHODS: Wistar rats were randomly divided into 5 groups, a normal group, a blank control (BC) group, a normal saline (NS) group, a lidocaine (LD) group and an amikacin (AK) group. For the latter 3 groups, normal saline, lidocaine and amikacin were injected into trachea by needle puncture. Scanning electron microscope was used to observe the ultra-structural changes of the epithelium, and the percentage of the area of damage (PAD) in tracheal mucosa was calculated. Moreover, pathological changes of the mucous membrane of bronchioles and alveolar epithelial cells were also examined, and the degree of lung pathology was semi-quantified. RESULTS: Two hours after the injection of the 3 drugs, derangement and edema of the cilia were evident by scanning electron microscopy. The PAD of the NS group, the LD group and the AK group were (94.2 ± 3.2)%, (93.1 ± 3.0)% and (95.5 ± 1.8)%, respectively; all being significantly higher than that of the BC group (1.3 ± 0.3)%. For the NS group and the LD group, the PAD decreased significantly after 24 h, which were (73.7 ± 7.8)% and (81.0 ± 4.6)% respectively, and returned to normal at 48 h and 96 h. While for the AK group, the damage began to improve at 72 h [PAD (62.1 ± 5.2)%], and recovered at 96 h. Airway epithelial derangement and cell edema in the alveoli and the bronchioles also occurred 2 h after drug injection, and inflammatory cell infiltration became evident at 24 h. At this time, the score of pathology was 1.80 ± 0.84, 2.60 ± 0.55 and 2.80 ± 0.45 for the NS group, the LD group and the AK group, respectively; all being higher than that of the BC group (0). These pathological changes recovered totally after 72 h for the NS and the LD groups, and 96 h for the AK group. CONCLUSIONS: Intra-tracheal administration of normal saline, lidocaine and amikacin in rats led to reversible airway mucosal and lung tissue damages.

[Pathological features and ultrastructure of N-methyl-N-nitrosourea (MNU)-induced thymic lymphomas in mice].

The objective of study was to investigate the origin and to classify the subtype of N-methyl-N-nitrosourea (MNU)-induced thymic lymphomas in mice. Histopathologic, immunohistochemical and ultrastructural studies were performed to analyze the pathological features of the neoplasms. The results showed that the thymus in all cases became totally replaced by sheets of cells of the lymphoid series. All the tumors coexpressed CD3 and TdT. Transmission electron microscopic study showed the plasma membranes of malignant lymphoma cells were smooth. The nuclear profiles were usually regular, with varying percentage of convoluted nuclei. Few cell organoids were observed in cytoplasm. In conclusion, all the MNU-induced tumor classified by histopathologic, immunohistochemical and ultrastructural studies as precursor lymphoblastic lymphoma that were unquestionably related to the thymus origin and T-cell lineage.

[Differential proteomic analysis of human colorectal carcinoma cell lines SW620 and SW480 with different metastatic potentials].

OBJECTIVE: To investigate differential protein expression profiles of human colorectal carcinoma cell lines with different metastatic potentials and screen metastasis-associated proteins for analyzing the relationship between metastasis-associated proteins and the tumorigenesis, progression and metastasis of colorectal carcinomas. METHODS: With two-dimensional electrophoresis (2-DE) and matrix assisted laser desorption/ionization-time of flight-mass spectrometry, we analyzed the differentially expressed proteins in two human colorectal carcinoma cell lines SW620 and SW480 with high and low metastatic potentials, and screened for proteins associated with colorectal carcinoma metastasis. RESULTS: Image analysis software Malenie III demonstrated good match and reproducibility of the 2-DE maps obtained from 3 independent experiments, with 1316+/-62 spots detected for SW620 cells and 1332+/-74 spots for SW480 cells with the average matching rate of 82% and 80%, respectively. The spots distributed in the greatest density at the isoelectric points of 4-7 and relative molecular mass weight of 20,000-70,000. Twenty-five distinctly different protein spots (14 spots for SW620 and 11 for SW480) in-gel digested by TPCK trypsin and 23 peptide mass fingerprint maps were obtained by mass spectrometry. Three highly matched proteins and 14 preliminarily matched proteins or fragments were obtained by analysis with Mascot software in the NCBInr database. Some of these differentially expressed proteins were related to gene transcription, cell cycle, signal transduction, cell apoptosis, etc, with possible involvement of cell differentiation, proliferation, invasion, adhesion, and metastasis of colorectal carcinoma. CONCLUSION: The 2-DE protein expression profile of SW620 cells with high metastatic potential displays obvious difference from that of SW480 cells with low metastatic potential, and a variety of proteins can be involved in the metastasis of colorectal carcinoma.