Pathology International最新文献

Hepatoid adenocarcinoma of the lung is a rare variant of adenocarcinoma. We describe a case of hepatoid adenocarcinoma of the lung that harbored KRAS G12C and responded favorably to sotorasib. A man in his 70s was found to have an abnormality on his chest X-ray. He underwent right middle lobectomy, and a pathological examination of the surgical specimen showed conventional invasive adenocarcinoma with highly focal hepatoid adenocarcinoma. He received chemoradiotherapy and concurrent radiation, followed by durvalumab for postoperative recurrence. After three doses of durvalumab, he reported feeling short of breath. A computed tomography scan showed emerging broad consolidation in the right lower lobe. Transbronchial lung biopsy specimens from the consolidation showed hepatoid adenocarcinoma harboring KRAS G12C mutation. Therefore, he was started on sotorasib 960 mg daily. Eight days later, a computed tomography scan showed that the area of consolidation had reduced in size. Progressive disease was detected after 42 days of treatment with sotorasib. The patient died 1 month after cessation of sotorasib and 3 months after postoperative recurrence. We have encountered what we believe to be the first case of hepatoid adenocarcinoma of the lung with KRAS G12C mutation that responded favorably to treatment with sotorasib.

Peripheral blood stem cell transplantation (PBSCT) has made amyloid light-chain (AL) amyloidosis treatable. After PBSCT, hematological complete remission (HCR) can be achieved, leading to improved renal prognosis. The purpose of this study was to evaluate whether whole slide imaging of biopsy samples shows a post-treatment reduction in amyloid deposits in patients with AL amyloidosis. Patients were divided into three groups: Group A (n = 8), not eligible for PBSCT and treated with other therapies; Group B (n = 11), treated with PBSCT and achieved HCR; and Group C (n = 5), treated with PBSCT but did not achieve HCR. Clinical findings and amyloid deposition in glomeruli, interstitium, and blood vessels were compared before and after treatment using digital whole-slide imaging. Proteinuria and hypoalbuminemia improved more in Group B than in the other groups, and in Group B, amyloid deposition improved more in the glomeruli than in the interstitium and blood vessels. The long-term renal and survival prognosis was better in Group B than in the other groups. PBSCT can be expected to improve long-term clinical and renal histological prognosis in patients with AL amyloidosis who achieve HCR. Amyloid disappearance from renal tissue may take a long time even after clinical HCR.

Linear nevus sebaceous syndrome (LNSS) is a neurocutaneous syndrome associated with systemic complications that involve multiple organs, including the skin, central nervous system, eyes, and skeleton. LNSS is considered to be caused by mosaic RAS gene mutation. In this report, we present an autopsy case of LNSS in a Japanese boy. The affected neonate had hydrops fetalis and was born at 28 weeks and 4 days of gestation, weighing 2104 g. He had bilateral inverted eyelids, verrucous linear nevus separated along Blaschko's line, myocardial hypertrophy, and pharyngeal constriction, and underwent intensive treatment in NICU for arrhythmia, hydrocephalus, and respiratory distress. The hydrocephalus progressed gradually and he died at the age of 181 days, 12 days after a sudden cardiac arrest and recovery. KRAS G12D mutation was found in a skin biopsy specimen but not in blood cells, suggesting a postzygotic mosaicism. Autopsy revealed novel pathological findings related to LNSS, including intracranial lipomatous hamartoma and mesenteric lymphangioma, in addition to previously reported findings such as multicystic dysplastic kidney. There was the limited expression of mutated KRAS protein in kidneys.

Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), a significant cancer stem cell marker in colorectal cancer (CRC), lacks lymph node (LN) expression studies. In this study, we identified LGR5 expression by RNAscope, a highly sensitive RNA in situ method, and analyzed its association with clinicopathological characteristics. Tissue microarrays were generated from primary tumors (PTs) and LN metastases in paraffin-embedded blocks of 38 CRC surgical resection materials. LGR5 expression by RNAscope was evaluated by dividing the expression levels into negative and positive expression. In all but two cases of LN metastasis, LGR5-positive dots were detected in tumor cells, and there was a wide range of LGR5-positive cells. More LGR5-positive dots were identified in the gland-forming region. Twenty-three cases were classified into a high LGR5-expression group, and 15 cases were classified into a low LGR5-expression group. In the high LGR5-expression group, the histological grade was lower than in the low LGR5-expression group (p = 0.0159), while necrosis was significantly more prevalent (p = 0.0326), and the tumor, node, metastasis stage was significantly lower (p = 0.0302). There was no association between LGR5 expression levels in LN metastases and LGR5 expression levels in PT tissue. LGR5 expression in LN metastases may influence prognosis. Further analysis may lead to new therapeutic strategies.

We conducted an autopsy on a 3-month-old boy in whom Kawasaki disease (KD) was strongly suspected based on the autopsy findings. The infant had a fever and was brought to a nearby clinic, where he was prescribed antipyretics and kept under observation. However, 15 days after onset of the fever, he suddenly died in bed. He exhibited no obvious redness of the lips, tongue, or conjunctiva. Membranous desquamation was present on his distal fingers. Vasculitis was observed in the coronary arteries, renal artery, splenic artery, and pulmonary vein. In addition, coronary artery aneurysms were present in the right coronary artery and left anterior descending artery. Thrombotic occlusion was observed in one aneurysm in the right coronary artery, resulting in acute myocardial infarction. The coronary artery wall showed infiltration of numerous macrophages and neutrophils. This case was classified as incomplete KD because the coronary artery aneurysm could not be demonstrated before death and was only recognized at autopsy. Pathologists and forensic scientists need to be aware that there are cases in which KD goes undiagnosed and untreated, leading to coronary artery aneurysm formation and sudden death.

Chronic liver injury induces liver cirrhosis and facilitates hepatocarcinogenesis. However, the effects of this condition on hepatocyte proliferation and differentiation are unclear. We showed that rodent hepatocytes display a ductular phenotype when they are cultured within a collagenous matrix. This process involves transdifferentiation without the emergence of hepatoblastic features and is at least partially reversible. During the ductular reaction in chronic liver diseases with progressive fibrosis, some hepatocytes, especially those adjacent to ectopic ductules, demonstrate ductular transdifferentiation, but the majority of increased ductules originate from the existing bile ductular system that undergoes extensive remodeling. In chronic injury, hepatocyte proliferation is weak but sustained, and most regenerative nodules in liver cirrhosis are composed of clonally proliferating hepatocytes, suggesting that a small fraction of hepatocytes maintain their proliferative capacity in chronic injury. In mouse hepatocarcinogenesis models, hepatocytes activate the expression of various fetal/neonatal genes, indicating that these cells undergo dedifferentiation. Hepatocyte-specific somatic integration of various oncogenes in mice demonstrated that hepatocytes may be the cells of origin for a broad spectrum of liver tumors through transdifferentiation and dedifferentiation. In conclusion, the phenotypic plasticity and heterogeneity of mature hepatocytes are important for understanding the pathogenesis of chronic liver diseases and liver tumors.

This paper illustrates a valve-sparing cardiac dissection technique that keeps the atrioventricular and semilunar valves and other important cardiac structures intact. The technique minimizes disruption in heart specimens, so they remain suitable for teaching, demonstration, and further research. When performed following the perfusion-distension method of fixation, as our group previously described, this technique could optimize the preservation of heart specimens for teaching and digital archiving postdissection.

Angiogenesis is considered essential for tumor progression; however, whether histological counting of blood vessel numbers, expressed as microvessel density (MVD), can be a prognostic factor in breast cancer remains controversial. It has been suggested that the specific morphology of blood vessels such as glomeruloid microvascular proliferation (GMP) is associated with clinical parameters. Here, we aimed to clarify the significance of MVD with revised immunohistochemistry and to identify new blood vessel shapes that predict prognosis in breast cancer. Four hundred and eleven primary breast cancer specimens were collected, and the sections were immunohistochemically stained with CD31 (single staining) and CD31 and Collagen IV (double staining). The prognosis of patients was examined based on the MVD value, and the presence of GMP and other blood vessels with other specific shapes. As a result, high MVD value and the presence of GMP were not associated with worse prognosis. By contrast, patients with deep-curved capillaries surrounding tumor cell nests (C-shaped) or excessively branched capillaries near tumor cell nests showed a significantly poor prognosis. The presence of these capillaries was also correlated with clinicopathological parameters such as Ki-67 index. Thus, the morphology of capillaries rather than MVD can be a better indicator of tumor aggressiveness.