Hepatocellular Carcinoma Presenting with Pseudoprogression in a Patient Receiving Atezolizumab Plus Bevacizumab Combination Therapy.

A 65-year-old man with hepatocellular carcinoma and lung metastasis was treated with a combination of atezolizumab and bevacizumab. Subsequently, the patient developed fever and new liver lesions, which were considered to indicate a pseudoprogression. Despite this, the treatment was continued.

Unique endoscopic features of primary biliary diffuse large B-cell lymphoma: A case report with literature review (with video).

A 67-year-old man visited our hospital complaining of dark-colored urine and upper abdominal pain. Magnetic resonance cholangiopancreatography showed stricture of the distal bile duct, and contrast-enhanced computed tomography showed irregular thickening of the distal bile duct wall. However, no enlarged lymph nodes, pancreatic tumors, or other neoplastic lesions were apparent around the bile duct.

A novel approach to diagnosing crystal-storing histiocytosis: utility of scanning electron microscopy for formalin-fixed paraffin-embedded tissue specimens.

Crystal-storing histiocytosis (CSH) is a rare disorder that shows infiltration of histiocytes with an aberrant cytoplasmic accumulation of crystalline structures and is often accompanied by lymphoproliferative-plasma cell disorders (LP-PCD) as background diseases. The diagnosis of CSH requires identification of crystalline structures that accumulate in the infiltrating histiocytes, which may be challenging by optical microscopy alone. In this case report, we describe an atypical course of systemic CSH with multifocal fibrosclerosis of an unknown background disease that was diagnosed by ultrastructural observation, including transmission electron microscopy (TEM) and scanning electron microscopy (SEM), in pathological autopsy.

Generalized crystal-storing histiocytosis with noncirrhotic portal hypertension: an autopsy case report.

Crystal-storing histiocytosis (CSH) is a rare disease associated with the accumulation of histiocytes containing crystalline matter within their cytoplasm. Herein, we present the case of a female patient who was diagnosed with Tolosa-Hunt syndrome at 45 years of age and idiopathic retroperitoneal fibrosis when she was 48 years. She developed portal hypertension (PH), but did not present with cirrhosis; as such, the cause of PH was not identified.

Diagnostic utility of CSF1 immunohistochemistry in tenosynovial giant cell tumor for differentiating from giant cell-rich tumors and tumor-like lesions of bone and soft tissue.

Background: Tenosynovial giant cell tumor (TSGCT) is a benign fibrohistiocytic tumor that affects the synovium of joints, bursa, and tendon sheaths and is categorized into localized TSGCT (LTSGCT) and diffuse TSGCT (DTSGCT). LTSGCT and DTSGCT are characterized by recurrent fusions involving the colony-stimulating factor 1 (CSF1) gene and its translocation partner collagen type VI alpha 3 chain. The fusion gene induces intratumoral overexpression of CSF1 mRNA and CSF1 protein.

Clinical and histopathologic effects of neoadjuvant intra-arterial chemoradiotherapy with cisplatin in combination with oral S-1 on stage III and IV oral cancer.

Objective: The aim of this study was to examine the clinical and histopathologic effects of neoadjuvant intra-arterial chemoradiotherapy (IACRT) using cisplatin in combination with oral S-1 (tegafur/gimeracil/oteracil potassium) on stage III and IV oral squamous cell carcinoma.

Study Design: Thirty patients received infusions of superselective intra-arterial cisplatin 60 mg/m by the Seldinger method and conventional external beam radiotherapy (total 40 Gy) combined with oral S-1 on the day of irradiation. Curative surgery and neck dissection were performed 4 to 6 weeks after IACRT.

Atypical spindle cell/pleomorphic lipomatous tumor with a sarcomatous component showing high mitotic activity and Ki-67 labeling index: report of a unique case mimicking dedifferentiated liposarcoma.

Atypical spindle cell/pleomorphic lipomatous tumor (ASPLT) is a new entity of benign adipocytic tumor that spans a wide spectrum of histology from adipocytic to spindle cell/pleomorphic tumors. The latter non-adipocytic component rarely shows sarcomatous features although ASPLTs are not thought to dedifferentiate. A 78-year-old woman with ASPLT in the left thigh had a sarcomatous component with high mitotic activity and Ki-67 labeling index (LI) mimicking dedifferentiated liposarcoma.

A Case of Unresectable Combined Hepatocellular-Cholangiocarcinoma Successfully Treated with Lenvatinib.

A 77-year-old man was referred to our hospital because of a hepatic tumor. Blood biochemistry showed elevated serum alfa-fetoprotein, protein induced by vitamin K absence-II, and carbohydrate antigen 19-9 levels. Gd-EOB-DTPA-enhanced magnetic resonance imaging revealed a 95-mm-sized tumor in liver S7.

Extensive mucosal sloughing of the small intestine and colon in a patient with severe COVID-19.

Patients with coronavirus disease 2019 (COVID-19) primarily cause respiratory symptoms. However, gastrointestinal (GI) symptoms can also occur. The endoscopic characteristics of the GI tract in COVID-19 patients remain unclear.

Assessment of H3K27me3 immunohistochemistry and combination of NF1 and p16 deletions by fluorescence in situ hybridization in the differential diagnosis of malignant peripheral nerve sheath tumor and its histological mimics.

Background: A definitive diagnosis of malignant peripheral nerve sheath tumor (MPNST) is challenging, especially in cases without neurofibromatosis 1 (NF1), because MPNST lacks specific markers on immunohistochemistry (IHC).

Methods: We performed IHC for histone 3 trimethylated on lysine 27 (H3K27me3) and evaluated the percentage of cells with H3K27me3 loss using measured values at 10% intervals, categorized as complete loss (100% of tumor cells lost staining), partial loss (10% to 90% of tumor cells lost staining), and intact (no tumor cells lost staining). We conducted fluorescence in situ hybridization (FISH) for NF1 and p16 deletions comparing 55 MPNSTs and 35 non-MPNSTs, consisting of 9 synovial sarcomas (SSs), 8 leiomyosarcomas (LMSs), 10 myxofibrosarcomas (MFSs), and 8 undifferentiated pleomorphic sarcomas (UPSs).

Case Report: Disappearance of Coronary Anastomotic Aneurysm by Steroid Therapy in Takayasu Arteritis: Pseudorepair of Pseudoaneurysm?

Takayasu arteritis (TA) is a large vessel vasculitis of unknown etiology characterized by chronic inflammatory changes of the aorta and its major branches. Complications such as anastomotic aneurysm and valve detachment have been reported in active TA patients who received aortic valve replacement and graft replacement of aorta. A 61-year-old man with a history of emergency aortic valve replacement and patch closure of the noncoronary sinus of Valsalva due to acute heart failure induced by acute aortic regurgitation and ruptured sinus of Valsalva 4 years ago was referred for exertional dyspnea.

Two cases of osteoblastic bone metastasis from muscle-invasive bladder cancer with discrepancy in response to chemotherapy: problems and limitations of bone biopsy.

We report two cases of muscle-invasive bladder cancer (MIBC) with increasing multiple osteoblastic bone lesions but shrinking other lesions in response to chemotherapy. Case 1 had MIBC and received radical cystectomy followed by adjuvant gemcitabine plus cisplatin chemotherapy (GC). Three years after, follow computed tomography (CT) showed development of multiple lymph node metastasis, and then we performed GC as a first-line systemic chemotherapy.

Fatal fulminant hepatitis induced by combined ipilimumab and nivolumab therapy despite favorable histologic response and confirmed by autopsy in a patient with clear cell renal cell carcinoma.

Effective management of immune-related adverse events in patients receiving immunotherapy for cancer is problematic. In this report, we present the case of a 58-year-old man with advanced clear cell renal cell carcinoma who responded well to a combination of ipilimumab and nivolumab. However, after two courses of treatment, he developed fulminant hepatitis and died.

Spindle cell rhabdomyosarcoma in a lumbar vertebra with FUS-TFCP2 fusion.

A 70-year-old woman developed severe buttock pain that progressed to a walking disturbance. Radiographs and computed tomography scans revealed an osteolytic lesion with osteosclerosis extending from the body to the arch of the fifth lumbar vertebra. Magnetic resonance imaging showed multinodular masses in the fifth lumbar vertebral body extending into the spinous processes and right transverse process.

Imprint cytology of biphenotypic sinonasal sarcoma of the paranasal sinus: A case report.

Biphenotypic sinonasal sarcoma (BSNS) is a rare low-grade spindle cell sarcoma that predominantly affects middle-aged women with multiple tumors in the sinonasal tract. BSNS shows biphenotypic expression of neural and myogenic markers on immunohistochemistry (IHC) with a specific chimeric PAX3-MAML3 fusion. The cytological features of BSNS have so far not been reported.

Detection of specific gene rearrangements by fluorescence in situ hybridization in 16 cases of clear cell sarcoma of soft tissue and 6 cases of clear cell sarcoma-like gastrointestinal tumor.

Background: Clear cell sarcoma of soft tissue (CCSST) and clear cell sarcoma-like gastrointestinal tumor (CCSLGT) are malignant mesenchymal tumors that share some pathological features, but they also have several different characteristics. They are well known to express chimeric fusions of Ewing sarcoma breakpoint region 1 (EWSR1) and cAMP response element-binding protein (CREB) family members; namely, EWSR1-activating transcription factor 1 (ATF1) and EWSR1-CREB1. In addition, recent studies have suggested the presence of other fusions.

Diagnostic utility of automated SureFISH (Dako Omnis) in the diagnosis of musculoskeletal translocation-related sarcomas.

Fluorescence in situ hybridization (FISH) is an essential tool for genetic diagnosis in daily pathological work. Almost full automation of FISH can be achieved with the recently released automated SureFISH platform (Dako Omnis, Agilent Technologies, Santa Clara, CA, USA). Its utility has been reported in HER2 amplification of breast and gastric carcinoma and ALK-rearranged lung cancer.