Antineutrophil cytoplasmic antibody-negative pauci-immune glomerulonephritis in a patient with Waldenstrom macroglobulinaemia.

Waldenstrom macroglobulinaemia (WM), the predominant subtype of lymphoplasmacytic lymphoma with bone marrow involvement and serum IgM paraprotein, is a haematological condition commonly associated with renal parenchymal involvement. However, antineutrophil cytoplasmic antibody (ANCA)-negative pauci-immune crescentic glomerulonephritis (PICGN) in kidney infiltrated by lymphoma is very rare, with only two cases described in chronic lymphocytic leukaemia in English literature so far. We herein report the first patient with WM developing ANCA-negative PICGN. He was a 76-year-old male who presented with elevated serum globulin level and bilateral groin lymph node enlargement, subsequently diagnosed to have WM after pathologic examination of the bone marrow and groin lymph node. One month later, he was found to have acute kidney injury and proteinuria. Renal biopsy confirmed the presence of parenchymal involvement by WM accompanied by PICGN; while ANCA testing was negative. He was treated with pulse methylprednisolone followed by oral prednisolone. In addition, six courses of intravenous rituximab and oral cyclophosphamide were given. There was significant improvement in both his renal and haematological conditions. The clinical course of this case suggested that ANCA-negative PICGN may represent a paraneoplastic syndrome and a rare manifestation of WM-associated renal lesion. Early kidney biopsy and prompt treatment may improve the outcome of patients.

IgG4-related lymphadenopathy.

IgG4-related lymphadenopathy is a nodal manifestation of IgG4-related disease (IgG4RD) which is characterized by increased polytypic IgG4+ plasma cells and IgG4+/IgG+ plasma cell ratio in lymph nodes and morphologically manifested as various patterns of reactive lymphadenopathy: Castleman disease-like, follicular hyperplasia, interfollicular expansion, progressive transformation of germinal centers and inflammatory pseudotumor-like. It typically presents with solitary or multiple, mild to moderate lymph node enlargement in otherwise asymptomatic patients. The serum IgG4 level is frequently elevated but C-reactive protein often remains normal. In patients not having a history of IgG4RD or manifestation of extranodal IgG4RD, a diagnosis of IgG4-lymphadenopathy should only be made with great caution given the non-specific morphologic features that can overlap with ANCA-associated vasculitis, interleukin-6 syndromes, Rosai-Dorfman disease, inflammatory myofibroblastic tumor, syphilis, lymphoma, and plasma cell neoplasia. Elevated IgG4 parameters, appropriate morphologies, and clinical correlation are essential to make the diagnosis of IgG4-lymphadenopathy more specific and clinically meaningful.

Systemic Involvement in Immunoglobulin G4-Related Ophthalmic Disease.

BACKGROUND: Immunoglobulin G4-related ophthalmic disease (IgG4-ROD) poses clinical challenges due to its heterogeneous ocular and systemic manifestations. We aim to report the systemic involvement and the clinical, serological and radiological associations of a cohort of Chinese patients. METHODS: A territory-wide, biopsy-proven, Chinese cohort. A retrospective, masked chart review of medical records, orbital images, and histopathology reports. RESULTS: A total of 122 (65 male) patients with a follow-up of 81 ± 49 (24 to 84) months were reviewed. Ninety (74%) patients presented bilaterally. Subacute upper eyelid swelling was the commonest presentation (82/122, 67%). During follow-up, 91/122 patients (75%) underwent extra-orbital imaging including computer tomography (692 films), ultrasonography (182 films), magnetic resonance imaging (76 films) and whole body FDG-PET scan (33 films). Eighty-six (95%) of these 91 patients had extra-orbital involvement radiologically (2.7 ± 1.6 regions, range: 0 to 9). Lymph node was the most prevalent (N = 60,66%), followed by salivary gland (N = 51,56%), lung (N = 49,54%), kidney (N = 22, 24%), hepatobiliary tree (N = 18, 20%) and pancreas (N = 17, 19%). Other organs include thyroid, aorta, meninges/brain and skin. Twenty-eight (23%) patients had allergic diseases (19 asthma, 16 allergic rhinitis, and 6 eczemas). Fifty-seven (48%) patients had paranasal sinusitis. Serum eosinophilia was associated with a higher number (3.24 versus 2.52, P = 0.0304) of organ involvement. Patients with deep organ involvement was associated with a higher age of IgG4-ROD onset (70 ± 12 versus 56 ± 13, P < 0.0001). CONCLUSIONS: 95% of the patients who underwent systemic imaging in our cohort had systemic organ involvement. An early physicians' assessment and radiological imaging are recommended after the diagnosis of IgG4-ROD.

Comparison of Clinical Outcomes, Pathologic Characteristics, and Immune-Related Features of Postradiation vs Sporadic Oral Cavity Squamous Cell Carcinoma.

Importance: Postradiation oral cavity squamous cell carcinoma (OCSCC) is a common secondary malignant neoplasm affecting survivors of head and neck cancer who underwent radiotherapy. The clinical, pathologic, and immune-related features of postradiation OCSCC are poorly characterized, and treatment options are limited because of surgical difficulty and high morbidity associated with reirradiation. Objective: To determine whether postradiation OCSCC has distinctive clinical, pathologic, and immune-related features compared with demographic-matched sporadic OCSCC. Design, Setting, and Participants: This retrospective matched cohort study was conducted at a single tertiary oncology center in Hong Kong. Participants included consecutive patients with OCSCC diagnosed between 2000 and 2020. Patients with postradiation OCSCC were matched with patients with sporadic OCSCC using age, year of diagnosis, sex, and anatomic subsites. Data analysis was performed from July to December 2022. Exposure: Head and neck irradiation involving the oral cavity before the diagnosis of OCSCC. Main Outcomes and Measures: The primary outcomes were relapse pattern, survival, and causes of death. Pathologic features; immunohistochemical staining for programmed death-ligand 1, PD-1, MSH6, PMS2, FOXP3, and Ki67; and mRNA expression of 31 immune-related genes were also analyzed. Results: A total of 173 patients, 60 with postradiation OCSCC (median [IQR] age, 63.8 [53.0-71.7] years; 43 men [71.7%]) and 113 with sporadic OCSCC (median [IQR] age, 64.4 [52.8-70.6] years; 83 men [73.5%]), were included. Patients with postradiation OCSCC had a higher proportion of N0 disease than those with sporadic OCSCC (50 patients [83.3%] vs 56 patients [49.6%]). With a median (IQR) follow-up of 10.2 (1.2-20.5) years, the 10-year relapse-free survival rates were lower in patients with postradiation OCSCC than sporadic OCSCC (29.6% [95% CI, 17.1%-43.2%] vs 52.4% [95% CI, 41.8%-62.0%]; P = .04), and the same was true for overall survival (30.5% [95% CI, 17.6%-44.4%] vs 52.3% [95% CI, 41.4%-62.1%]; P = .03). All relapses in patients with postradiation OCSCC were locoregional, whereas 35.2% of relapses (12 of 34 patients) in patients with sporadic OCSCC were distant. Despite similar 10-year disease-specific survival rates between the 2 groups (68.8% [95% CI, 55.8%-81.0%] vs 67.1% [95% CI, 57.5%-76.5%]; P = .91), patients with postradiation OCSCC had excess mortality due to pneumonia and cerebrovascular events. Postradiation OCSCC exhibited more adverse pathologic features (perineural invasion, worse pattern of invasion, and tumor budding), higher PD-1 expression, and higher gene expression of CD4 and TGF-ß compared with sporadic OCSCC. Conclusions and Relevance: This retrospective matched cohort study found distinctive pathologic characteristics and relapse patterns of postradiation OCSCC compared with sporadic OCSCC, which may be attributable to the lack of adjuvant radiotherapy, aggressive biologic phenotype, and different host immune response. Further exploration of the role of immune checkpoint therapy may be justified.

EBV-negative Fibrin-Associated Large B-Cell Lymphoma Arising in Thyroid Hyperplastic Nodule: Report of a Case and Literature Review.

Fibrin-associated large B-cell lymphoma is a rare microscopic-sized tumor, typically representing an unexpected finding at sites rich in chronic fibrin deposition. It is associated with Epstein-Barr virus, and has been reported to occur in a wide variety of anatomic sites and clinical scenarios. We report a case arising in a thyroid hyperplastic nodule, only the second case reported in this location. Notably, this is only the fourth case of fibrin-associated large B-cell lymphoma that is not associated with Epstein-Barr virus. We provide a literature review on the clinico-pathological characteristics and outcome of this newly characterized indolent lymphoma type, which has only recently been separated out from the pathologically similar but highly aggressive large B-cell lymphoma associated with chronic inflammation.

Bilateral synchronous conjunctival myxoma and review of the literature.

PURPOSE: The purpose of this study was to report the clinicopathological features and management of the first case of bilateral synchronous conjunctival myxoma. METHODS: This study was a case report and literature review. RESULTS: A 66-year-old Chinese male with past ocular history of uncomplicated bilateral phacoemulsification and intraocular lens (IOLs) 3 years ago prior to presentation presented with bilateral red and swollen conjunctiva for over a year. On examination his corrected distance visual acuity (CDVA) was 25/20 in the right eye 20/20 in the left eye. Slit lamp examination revealed swollen temporal conjunctiva bilaterally which appeared as painless, well-circumscribed, salmon-pink, fleshy patches. The lesion in the right eye was subsequently excised, followed by excision of the lesion in the left eye at 3-week interval. Microscopically, histopathological examination of both excised specimens revealed hypocellular conjunctival mucosa covered by non-dysplastic epithelium, with presence of myxoid degeneration in the subepithelial stroma and immunostaining findings consistent with conjunctival myxoma. At his latest follow-up at 24 months, there were no recurrences of the conjunctival masses and the CDVA was the same as preoperatively.

Adenofibromatous Solitary Fibrous Tumor: An Unusual Morphologic Variant Occurring in the Sinonasal Tract.

BACKGROUND: Solitary fibrous tumor can exhibit a broad morphologic spectrum, such as presence of epithelioid tumor cells, adipose cells and multinucleated giant cells. This report describes an unusual morphologic variant characterized by adenofibromatous features, all occurring in the sinonasal region. METHODS: Four cases of the adenofibromatous variant of solitary fibrous tumor were retrieved from the surgical pathology and consultation files in Queen Elizabeth Hospital, Hong Kong. Histologic examination, immunohistochemical study and reverse-transcription polymerase chain reaction (RT-PCR) were performed. RESULTS: The patients were adults who presented with an obstructive mass of the nasal septum, nasal cavity or nasolacrimal sac. Histologic examination showed a circumscribed biphasic tumor with intermingling of glandular structures and spindle cells, reminiscent of mammary fibroadenoma. Bland-looking spindle cells formed short, irregularly oriented fascicles, admixed with variable amount of collagen fibers. The glandular component comprised ducts and seromucinous acini with a lobular architecture, indicating that it represented exuberant hyperplasia of indigenous glands rather than part of the neoplastic process. Demonstration of CD34 and STAT6 immunoreactivity in the spindle cells and NAB2::STAT6 gene fusion by polymerase chain reaction supports the diagnosis of solitary fibrous tumor. CONCLUSION: This study reports four cases of sinonasal solitary fibrous tumor with adenofibromatous features, furthermore expanding the morphologic spectrum of this tumor.

The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Lymphoid Neoplasms.

We herein present an overview of the upcoming 5th edition of the World Health Organization Classification of Haematolymphoid Tumours focussing on lymphoid neoplasms. Myeloid and histiocytic neoplasms will be presented in a separate accompanying article. Besides listing the entities of the classification, we highlight and explain changes from the revised 4th edition. These include reorganization of entities by a hierarchical system as is adopted throughout the 5th edition of the WHO classification of tumours of all organ systems, modification of nomenclature for some entities, revision of diagnostic criteria or subtypes, deletion of certain entities, and introduction of new entities, as well as inclusion of tumour-like lesions, mesenchymal lesions specific to lymph node and spleen, and germline predisposition syndromes associated with the lymphoid neoplasms.

Spindle cell/sclerosing rhabdomyosarcoma with DCTN1::ALK fusion: broadening the molecular spectrum with potential therapeutic implications.

Spindle cell/sclerosing rbabdomyosarcoma (RMS) is a recently characterized variant of RMS with several distinct molecular subtypes. We describe an example occurring in the tongue of a 10-year-old boy with a novel DCTN1::ALK fusion. The tumor exhibited infiltrative growth and was comprised of fascicles and focally whorls of spindle cells with eosinophilic cytoplasm, in a collagenous or myxoid stroma. Moderate cytologic atypia, mitotic activity (2/10 HPFs), and perineural invasion were identified. The tumor cells expressed actin, desmin, MyoD1, myogenin, and ALK. An in-frame fusion between DCTN1 exon 26 and ALK exon 20 was detected by RNA sequencing, which was confirmed by split reads and supported by FISH studies. The tumor showed an indolent behavior with local recurrence 3 years after excision. This study broadens the molecular spectrum of spindle cell/sclerosing RMS and this molecular aberration may represent a potential therapeutic target for unresectable or disseminated disease.

Brucein D augments the chemosensitivity of gemcitabine in pancreatic cancer via inhibiting the Nrf2 pathway.

BACKGROUND: Gemcitabine (GEM) is the first-line chemotherapeutic drug used to treat pancreatic ductal adenocarcinoma carcinoma (PDAC), but chemoresistance is often encountered clinically. Nrf2, an oxidative stress responsive transcription factor, is an important contributor to chemoresistance and poor prognosis of PDAC. Brucein D (BD), a naturally occurring quassinoid, has been reported to exert anti-tumor effect in several cancers including PDAC. In this study, we aimed to investigate the efficacy of BD and the role of Nrf2 axes on the chemosensitivity of GEM and elucidate the underlying molecular mechanisms. METHODS: Analyses of clinical samples of PDAC and GEPIA database were first conducted to identify the expression of Nrf2 in PDAC. We then established cell lines with stable deletion of Nrf2 through transfecting lentivirus into PDAC cells. Quantitative real-time PCR (qRT-PCR) and Western blotting were performed to determine the expression of Nrf2 in these cell lines. The effects of BD and Nrf2 axes on PDAC cell proliferation, colony-formation, tumor growth and chemosensitivity were determined both in vitro and in vivo. Orthotopic xenograft and genetically engineered KPC mouse models of PDAC were used to evaluate the anti-pancreatic cancer effects of BD and GEM. RESULTS: Nrf2 was highly expressed in PDAC in the clinical samples and GEPIA analysis. Gain- and lost-function study demonstrated that Nrf2 affected the chemosensitivity of GEM on PDAC cells both in vitro and in vivo. We further found that BD effectively inhibited PDAC cell proliferation and enhanced the chemosensitivity of GEM. Mechanistic studies revealed that BD sensitized GEM in PDAC cells through the ubiquitin-proteasome-dependent degradation of Nrf2, and downregulating the Nrf2 pathway. Silencing of Nrf2 plus BD treatment resulted in more potent inhibitory effects of GEM. In contrast, Nrf2 activation attenuated the chemosensitivity of GEM, indicating that the action of BD was Nrf2 dependent. Finally, the efficacy of BD alone and in combination with GEM on PDAC was validated on both orthotopic xenograft and genetically engineered KPC mouse models. CONCLUSIONS: BD was able to enhance the chemosensitivity of GEM in PDAC through inhibition of the Nrf2 pathway. Our experimental findings indicate that BD, a potent Nrf2 inhibitor, holds promise for further development into a novel adjuvant therapy for PDAC.

Deep RNA Sequencing Revealed Fusion Junctional Heterogeneity May Predict Crizotinib Treatment Efficacy in ALK-Rearranged NSCLC.

INTRODUCTION: Gene fusion variants in ALK-rearranged NSCLC may predict patient outcomes, but previous results have been inconclusive. Fusion isoforms coexisting in the same tumor may affect the efficacy of targeted therapy, but they have not been investigated. METHODS: Patients with ALK-rearranged NSCLC who received crizotinib treatments were recruited. Precrizotinib tumor tissues were analyzed by the anchored multiplex polymerase chain reaction for targeted RNA sequencing. Kaplan-Meier and Cox regression were used to compare overall and progression-free survivals. RESULTS: Of the 51 studied subjects, EML4-ALK variant types v1, v2, v3, and others were detected in 23 (45.1%), five (9.8%), 19 (37.3%), and four patients (7.8%), respectively. Multiple EML4-ALK RNA isoforms were detected in 24 tumors (47.1%), and single isoform in 27 (52.9%). Most of the v3 tumors (16 of 19) harbored both v3a and v3b RNA isoforms. Multiple isoforms were also detected in eight non-v3 tumors (33.3% of all 24 multiple isoforms; five v1, two v5', and one v2). Compared with patients with single isoform, those with multiple isoforms had worse progression-free (hazard ratio and 95% confidence interval: 2.45 [1.06-5.69]) and overall (hazard ratio [95% confidence interval]: 3.74 [1.26-11.13]) survivals after adjusting for potential confounders including variant type. Using the patient-derived H2228 cells known to express v3a and v3b, our single-cell polymerase chain reaction detected either v3a or v3b in most single cells. Treatment of H2228 cells by three ALK inhibitors revealed increased ratios of v3a-to-v3b expression over time. CONCLUSIONS: Intratumoral EML4-ALK isoforms may predict the efficacy of targeted therapy in ALK-rearranged NSCLC. Temporal changes of intratumoral fusion isoforms may result from differential selection pressures that a drug might have on one isoform over another. Larger studies on fusion heterogeneity using RNA sequencing are warranted.

TCOF1 upregulation in triple-negative breast cancer promotes stemness and tumour growth and correlates with poor prognosis.

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with poor prognosis. By performing multiomic profiling, we recently uncovered super-enhancer heterogeneity between breast cancer subtypes. Our data also revealed TCOF1 as a putative TNBC-specific super-enhancer-regulated gene. TCOF1 plays a critical role in craniofacial development but its function in cancer remains unclear. METHODS: Overall survival and multivariant Cox regression analyses were conducted using the METABRIC data set. The effect of TCOF1 knockout on TNBC growth and stemness was evaluated by in vitro and in vivo assays. RNA-seq and rescue experiments were performed to explore the underlying mechanisms. RESULTS: TCOF1 is frequently upregulated in TNBC and its elevated expression correlates with shorter overall survival. TCOF1 depletion significantly inhibits the growth and stemness of basal-like TNBC, but not of mesenchymal-like cells, highlighting the distinct molecular dependency in different TNBC subgroups. RNA-seq uncovers several stem cell molecules regulated by TCOF1. We further demonstrate that KIT is a downstream effector of TCOF1 in mediating TNBC stemness. TCOF1 expression in TNBC is regulated by the predicted super-enhancer. CONCLUSIONS: TCOF1 depletion potently attenuates the growth and stemness of basal-like TNBC. Expression of TCOF1 may serve as a TNBC prognostic marker and a therapeutic target.

Defining super-enhancer landscape in triple-negative breast cancer by multiomic profiling.

Breast cancer is a heterogeneous disease, affecting over 3.5 million women worldwide, yet the functional role of cis-regulatory elements including super-enhancers in different breast cancer subtypes remains poorly characterized. Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a poor prognosis. Here we apply integrated epigenomic and transcriptomic profiling to uncover super-enhancer heterogeneity between breast cancer subtypes, and provide clinically relevant biological insights towards TNBC. Using CRISPR/Cas9-mediated gene editing, we identify genes that are specifically regulated by TNBC-specific super-enhancers, including FOXC1 and MET, thereby unveiling a mechanism for specific overexpression of the key oncogenes in TNBC. We also identify ANLN as a TNBC-specific gene regulated by super-enhancer. Our studies reveal a TNBC-specific epigenomic landscape, contributing to the dysregulated oncogene expression in breast tumorigenesis.

Pseudoaneurysm formation and rupture after stereotactic radiotherapy for cerebral arteriovenous malformation: a case report and review of literature.

We report a rare delayed complication of de novo pseudoaneurysm formation and rupture after stereotactic radiotherapy for cerebral arteriovenous malformation. The patient presented with intracerebral haemorrhage due to rupture of a pseudoaneurysm in the previously irradiated field, which was excised for histological examination. The literature was reviewed for similar cases.

"Pauci-Hemosiderotic" Fibrolipomatous Tumor: A Mimicker of Various Lipomatous Lesions.

Hemosiderotic fibrolipomatous tumor is a rare soft tissue tumor that preferentially affects the dorsum of foot, shows recurrent t(1;10) translocation targeting TGFBR3 and OGA (MGEA5) genes, and has a high recurrence potential. Hemosiderin deposits, mature adipocytes, and interspersed spindle cells are the 3 cardinal morphologic features of this tumor. We describe a "pauci-hemosiderotic" example involving the left wrist of a 45-year-old female, posing a diagnostic pitfall. The tumor comprised mature adipose tissue traversed by variably thick fibrous septa containing short fascicles of spindle cells. Prominent small- to medium-sized blood vessels were present, often with perivascular fibrosis or aggregates of foamy histiocytes, sometimes associated with red cell extravasation. Hemosiderin was not conspicuous, but fine deposits could be found focally on careful search and with the aid of Perls stain. The diagnosis was further confirmed by diffuse expression of CD34 and presence of OGA translocation by fluorescence in situ hybridization. Pathologists should be aware that hemosiderin deposition can be scanty and focal in hemosiderotic fibrolipomatous, but the rich vasculature with a "damaged" appearance is a useful diagnostic clue.

Ocular PEComas are frequently melanotic and TFE3-translocated: report of two cases including the first description of PRCC-TFE3 fusion in PEComa.

Ocular perivascular epithelioid cell tumor (PEComa) is exceedingly rare. We reported two examples involving the choroid and subconjunctival tissue, respectively, in patients aged 17 and 20 years. Both tumors comprised packets and sheets of large polygonal cells with moderately pleomorphic nuclei and prominent nucleoli, traversed by delicate fibrovascular septa. Melanin pigmentation was present in one case. The tumors showed HMB45 and TFE3 immunoreactivity. TFE3 gene translocation was confirmed by FISH break-apart probes. RNA seq revealed PRCC-TFE3 and NONO-TFE3 fusions, with the former representing the first description of PRCC-TFE3 in PEComa. Critical reappraisal of the reported cases showed that ocular PEComa frequently affected young patents with melanin pigmentation, frequent TFE3 protein expression, and/or TFE3 gene translocation. No recurrence or metastasis was reported after complete excision despite the presence of cytologic atypia.

New Clinicopathologic Scenarios of EBV+ Inflammatory Follicular Dendritic Cell Sarcoma: Report of 9 Extrahepatosplenic Cases.

EBV+ inflammatory follicular dendritic cell (FDC) sarcoma is an indolent malignant neoplasm of spindled FDCs with a rich lymphoplasmacytic infiltrate and a consistent association with Epstein-Barr virus (EBV). It occurs exclusively in the liver and spleen, with the exception of a few colonic examples. In this study, we report 9 extrahepatosplenic cases, including 4 occurring in previously undescribed sites, but all apparently anatomically related to the aerodigestive tract. The cases included 5 gastrointestinal tumors all presenting as colonic pedunculated polyps, 2 presenting as mesocolon mass, and 2 involving the palatine or nasopharyngeal tonsils. One patient with a colonic tumor was complicated by paraneoplastic pemphigus. The patients had a median age of 58 years, with female predominance (female:male=7:2). A favorable outcome was observed in 7 patients. Histologically, EBV+ inflammatory FDC sarcomas arising from these anatomic sites were similar to their hepatosplenic counterparts. Spindled to oval neoplastic cells with ill-defined cell borders were dispersed or formed loose whorled fascicles in a dense lymphoplasmacytic background. They had vesicular nuclei with distinct nucleoli and typically exhibited a range of nuclear atypia in the same case. The neoplastic cells showed variable expression of FDC markers and were labeled for Epstein-Barr virus-encoded RNA on in situ hybridization. These 9 cases thus broaden the clinicopathologic scenarios of EBV+ inflammatory FDC sarcoma. Recognition of the potential existence of this tumor type in extrahepatosplenic sites permits a correct diagnosis to be made.