Identification of characteristic subepithelial surface granulomatosis in immune-related adverse event-associated enterocolitis.

Immune checkpoint inhibitors (ICIs) have provided an additional treatment option for various types of human cancers. However, ICIs often induce various immune-related adverse events (irAEs). Enterocolitis is a major irAE with poorly understood histopathological characteristics. In this study, we retrospectively investigated the histopathology of colon tissue samples from 17 patients treated with ICIs. There were two major histological patterns of colitis: an ulcerative colitis-like pattern and a graft vs host disease-like pattern. Although these two patterns of colitis were mutually exclusive, both patterns often showed a characteristic that we call "subepithelial surface granulomatosis" (SSG), which has not been reported in other types of colitis. SSG was found even in colon tissue without symptoms or endoscopic findings of colitis. Given the increasing reports of sarcoid reaction or exacerbation of tuberculosis after treatment with ICIs, granuloma formation could be a histological hallmark of systemic immune activation by ICIs. Although statistical significance was not obtained, probably because of the small sample size, SSG may be a surrogate biomarker of systemic anticancer immune activation. We propose that a prospective study with larger sample size be performed.

[Philadelphia chromosome-positive acute lymphoblastic leukemia with basophilic blast features].

A 62-year-old man was referred to our hospital due to pancytopenia and abnormal leukocyte fraction in December 2016. Bone marrow aspiration showed a massive proliferation of blast cells (96%) with rich myeloperoxidase-negative basophilic granules. He was diagnosed with acute basophilic leukemia, and an appropriate treatment for acute myelogenous leukemia was initiated. Blast cells were positive for minor BCR-ABL mutations, and chemotherapy using imatinib was initiated on day 7. The treatment was effective and complete remission was achieved on day 30. The ultrastructural features of blast cells showed typical basophilic granules with high electron density structure on electron microscopy. However, immunohistochemical analysis were positive for CD79a, PAX5, and TdT expression. Rearrangements of immunoglobulin heavy chain and T-cell receptor genes were detected, prompting the diagnosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) with basophilic change. The patient continued to be treated with the imatinib combination regimen, as well as umbilical cord blood transplantation. The patient has currently achieved recurrence-free survival. This case represents a rare divergence between morphology and molecular condition.

Dedifferentiated liposarcoma primary to the chest wall with spontaneous shrinking: report of a case.

An 80-year-old man presented to our emergency department complaining of a mass on the right side of his chest and pain in the right flank of his back. A chest computed tomography (CT) scan showed a relatively heterogenous oval-shaped tumor measuring 7.5 × 6.0 cm eroded to the 8th rib, with slightly dense fluid accumulation inside and calcification of the tumor wall. A 1-month follow-up CT scan showed spontaneous shrinkage of the tumor. The tumor was completely excised from the thoracic wall and the wall was reconstructed with a polytetrafluoroethylene mesh. Pathological examination showed coagulation necrosis in the chest wall tumor, but immunohistochemical staining revealed murine double minute 2- and Cyclin-dependent kinase 4-positive cells with irregular nuclear size and bizarre morphology. Therefore, dedifferentiated liposarcoma (DDLPS) was the final pathological diagnosis. Remarkable infiltration of CD8+ lymphocytes into the tumor was observed, along with a 90% positive ratio for programmed cell death-ligand 1. The patient has been followed-up for 1 year without any recurrence, despite not receiving any additional treatment. Liposarcoma is one of the most common types of soft tissue sarcomas; however, spontaneous regression of primary DDLPS arising from the chest wall is extremely rare. Herein, we report a case of DDLPS primary to the chest wall with spontaneous regression, probably due to a spontaneously induced T cell response.

Immunohistochemical analysis of arachidonate 5-lipoxygenase expression in B-cell lymphomas: Implication for B cell differentiation and its analogy with lymphomagenesis.

Arachidonate 5-lipoxygenase (ALOX5) is a cardinal enzyme in the synthesis of leukotrienes, which are powerful immune-regulating lipid mediators. We previously reported that ALOX5 is preferentially expressed in B lymphocytes in the mantle zone of human lymphoid tissue. In the context of physiological relevance, the loss of the Alox5 gene in mice significantly impairs the development of follicular B helper T cells and antibody production. However, ALOX5 expression in B-cell lymphomas has not been investigated in detail. In this study, we examined ALOX5 expression in representative B-cell lymphomas and non-neoplastic lymphoid tissues by immunohistochemistry with a commercially available anti-ALOX5 antibody that can be used on formalin-fixed paraffin-embedded specimens. Interestingly, 22/22 cases of mantle cell lymphoma, 7/7 cases of chronic lymphocytic leukemia/small cell lymphoma, and 20/20 cases of follicular lymphoma expressed ALOX5. A small proportion of extranodal marginal zone lymphoma/mucosa-associated lymphoid tissue lymphoma or nodal marginal zone lymphoma cases were positive for ALOX5 (2/13 or 1/3, respectively). In contrast, no cases with diffuse large B-cell lymphoma, regardless of germinal center B cell (GCB) or non-GCB type, expressed ALOX5 (0/25 cases). These findings suggest that ALOX5 may be a novel marker for identifying the cell of origin of B-cell lymphoma. Further investigation is required to clarify the biological significance of ALOX5 expression in lymphoma cells.

[Effective treatment by both anti-androgen therapy and chemotherapy for a patient with advanced salivary duct carcinoma].

Salivary ductcarcinoma (SDC)is a high-grade malignant tumor arising predominantly in the parotid gland. Androgen receptor(AR)expression was mainly restricted to SDC in salivary cancer. We report successful treatment of a patient with advanced SDC using an endocrine chemotherapy. A 76-year-old man was hospitalized with lumbalgia and swelling of left submandibular region. Radiological examination indicated a tumor in left submandibular gland and metastatic tumors in lumbar vertebra, accompanied by swollen lymph nodes of the neck, mediastinum. Needle biopsies of both vertebral tumor and cervical lymph node revealed SDC. Positive nuclear staining was observed against AR in tumor cells of our patient by immunohistochemical analysis. He obtained a partial response after 1 course of treatment with both anti-androgen therapy and palliative chemotherapy using paclitaxel. In contrast to previous reports of poor response to chemotherapy alone and short-term survival of patients with SDC, our patient has demonstrated that chemotherapy combined with anti-androgen therapy may be an effective modality as a therapeutic regimen for SDC.

Improvement of abnormal cervical cytology possibly due to a graft-versus-tumor effect: A case report and literature review.

The cervical cytology of our patient transformed from squamous cell carcinoma to negative for intraepithelial lesion or malignancy, possibly due to the graft-versus-tumor effect following allogeneic stem cell transplantation.

A Radical Approach to Acute Lymphoblastic Leukemia Treatment: A Case Study of a Veterinarian Specializing in Livestock who Developed Disseminated Mucormycosis during Induction Therapy.

Mucormycosis has emerged as the third-most common fungal mycosis and is one of the most fatal molds. We herein report a case study of a 30-year-old woman who was a veterinarian, specializing in livestock, who developed disseminated mucormycosis during induction therapy for acute lymphoblastic leukemia. We successfully used a radical approach for treatment, including a surgical procedure and allogeneic transplantation, with continuous administration of antifungal agents. Reports of successful treatments are extremely rare, and our case has had the longest documented remission from disseminated disease. We speculate that our case's occupational environment may represent a risk factor for development of mucormycosis.

Rare Clinical Course of Immunoglobulin G4-Related Inflammatory Abdominal Aortic Aneurysm with Multiple Rare Complications.

Immunoglobulin G4- (IgG4-) related inflammatory abdominal aortic aneurysm (AAA) has been recognized as a manifestation of IgG4-related disease (IgG4-RD). We experienced one patient with multiple consecutive manifestations before and after endovascular stent grafting for IgG4-related inflammatory AAA (IAAA). A 71-year-old man was diagnosed with IgG4-RD due to increased IgG4 serum concentration, typical findings of parotid gland biopsy, and periaortitis in another hospital 2 years and 7 months before visiting our hospital. He came to our hospital because of abdominal pain and IAAA. He developed paraplegia after hospitalization and underwent endovascular stent grafting for the IAAA. About one month after stent grafting, he developed perforation of the sigmoid colon due to enteritis. He also had myocardial infarction. Finally, he died of intestinal bleeding. Here, we describe this case with rare, multiple, consecutive manifestations of IgG4-RD, some of which might be caused by IgG4-related IAAA or side effects of treatments rather than by IgG4-RD itself. We report this case because the clinical course seemed rare for IgG4-RD or IgG4-related IAAA. For treating IgG4-RD with IgG4-related IAAA, we should consider factors causing the symptoms and carefully select the proper treatment.

Zygomycotic invasion of the central nervous system.

Zygomycosis is an opportunistic fungal infection that affects the central nervous system (CNS). In this report, we present three cases of zygomycosis with CNS involvement. In two patients zygomycosis developed after neurosurgery, and in the third patient zygomycosis developed after bone marrow transplantation for leukemia. All patients developed persistent fever and neurological deficits. They presented with progressive cerebral infarction accompanied by hemorrhage. Intraoperative findings and histopathological examinations revealed that zygomycotic hyphae caused mycotic aneurysm, vasculitis, and venous occlusion.

Cyclin D1 over-expression correlates with beta-catenin activation, but not with H-ras mutations, and phosphorylation of Akt, GSK3 beta and ERK1/2 in mouse hepatic carcinogenesis.

Mutational activation of beta-catenin and cyclin D1 over-expression are a frequent change in mouse hepatic tumors. Although activated beta-catenin may bind to T cell factor (TCF) family members and transcriptionally activate the cyclin D1 gene, either beta-catenin or cyclin D1 may be activated by various pathways independently of beta-catenin mutations. In this study, we investigated beta-catenin activation and mutations, cyclin D1 expression, H-ras mutations and phosphorylation of extracellular signal regulated protein kinases 1/2 (ERK1/2), Akt and glycogen synthetase kinase 3beta (GSK3 beta) in mouse hepatic carcinogenesis. Nuclear/cytoplasmic staining of beta-catenin, a sign of beta-catenin activation, was frequently observed in association with the high nuclear cyclin D1 labeling index in the hepatic tumors at the late stage of carcinogenesis. The beta-catenin activation was further suggested by the fact that all hepatocellular carcinoma (HCC) cell lines examined showed the nuclear beta-catenin/TCF4 complex together with cyclin D1 over-expression. However, the fact that only 31.8% (7/22) of the lesions with the nuclear/cytoplasmic beta-catenin staining showed beta-catenin mutations indicated that beta-catenin was activated not only by its own mutations but also by other reason(s). On the other hand, there was no correlation between the beta-catenin/cyclin D1 activation and the H-ras mutations or phosphorylation of Akt, GSK3 beta and ERK1/2, although GSK3 beta was frequently over-expressed in the tumors. These results indicate that, although beta-catenin and cyclin D1 activation are well correlated, the Akt/GSK3 beta and ras/ERK1/2 pathways may not play a major role in the beta-catenin/cyclin D1 activation.