Increased IgG4+ plasma cells are common in excised lymph nodes from children and adolescents without IgG4-related disease.

Lymphadenopathy is a common finding in patients with IgG4-related disease (IgG4-RD) and often associated with increased IgG4+ plasma cells in this setting. The histologic features of so-called IgG4-related lymphadenopathy (IgG4-LAD) have seldom been investigated in children and adolescents, and step-wise progression to extranodal IgG4-RD has not been described. This study was performed to further evaluate the frequency, pathologic features, and clinical significance of IgG4-LAD-like histologic changes in the pediatric setting. We analyzed 37 benign lymph nodes collected semi-consecutively from children aged 0-18 years at our institution for both absolute and relative IgG4+ plasma cell abundance and recurrent histomorphologic patterns associated with IgG4-LAD. The combination of IgG4+/IgG+ plasma cell ratio >40% and IgG4+ plasma cell count ≥50 were considered as IgG4-LAD-like per expert consensus guidelines. Seven cases (19%) met both diagnostic criteria. The dominant histomorphologic patterns were follicular hyperplasia (n = 6), interfollicular expansion (n = 3), and progressive transformation of germinal centers (n = 3). Extranodal manifestations of IgG4-RD were not identified in this cohort (38 months average follow-up). Instead, clinical and laboratory findings indicated that lymph node enlargement in most patients could likely be attributed to alternative processes including antecedent dentistry, concurrent infection, and incipient Crohn's disease. Our findings suggest that the histologic features of IgG4-LAD are likely much more common in children and adolescents than previously recognized, often existing in complex with common reactive lymphadenopathies. The diagnostic value of routine immunohistochemical assessment for IgG4+ plasma cells in benign lymph nodes from pediatric patients without established extranodal IgG4-RD and/or other supportive clinical and laboratory data is therefore uncertain.

Minimal Change Disease Secondary to Graft-versus-Host Disease after Allogeneic Hematopoietic Cell Transplant for Myelodysplastic Syndrome.

Chronic graft-versus-host disease (cGVHD) is a leading cause of non-relapse mortality in allogeneic hematopoietic cell transplant (HCT) recipients. While the current standard of care is proactive in detecting cGVHD in the lungs, liver, and skin, cGVHD involving kidneys is an underrecognized and likely underdiagnosed cause of post-HCT renal dysfunction. Nephrotic syndrome (NS) is a very rare complication of HCT that is postulated to be a glomerular manifestation of cGVHD. Herein, we report 2 cases of post-HCT minimal change disease likely secondary to cGVHD. In both cases, the onset of NS coincided with tapering of calcineurin inhibitors, and 1 patient had previously been diagnosed with cGVHD of the lungs. One patient was treated with corticosteroids alone and the other with a corticosteroids and tacrolimus. Complete, sustained remission was achieved in both cases. Our cases illustrate the implications of the association between cGVHD and post-HCT NS for patient care, including the importance of obtaining a renal biopsy to establish an accurate histopathological diagnosis and guide-appropriate treatment.

Successful treatment of metastatic pancreatoblastoma in an adult with autologous hematopoietic cell transplant.

BACKGROUND: Pancreatoblastoma is a rare pediatric malignant neoplasm characterized by its histological resemblance to fetal pancreatic tissue and poor clinical outcomes. Preoperative diagnosis of the neoplasm is difficult due to its rarity, variable clinical presentation, and its lack of distinct laboratory markers. Current mainstay of treatment is surgical resection of the tumor, although a standard of care has not yet been established. METHODS: Data were collected on one patient admitted to the University of Virginia Hospital System. Radiology, hematopoietic cell transplant, and biopsy data were collected according to the best clinical practice. RESULTS: Herein, we describe the case of an adult patient with pancreatoblastoma treated with high-dose chemotherapy and autologous peripheral blood hematopoietic cell transplantation. To the authors' knowledge, this is the first documented successful treatment of pancreatoblastoma using autologous hematopoietic cell transplantation in the United States, and the first successful treatment in an adult patient worldwide. CONCLUSIONS: While it is difficult to draw conclusions based on a single case, we would like to highlight the success of this treatment modality in the management of our patient with a 51-month remission and open further discussion into exploring the use of autologous hematopoietic cell transplantation for pancreatoblastoma. Our patient is currently living 57 months after diagnosis despite the average survival rate being less than 18 months.

Emerging biomarkers in ovarian granulosa cell tumors.

OBJECTIVE: Although the majority of ovarian granulosa cell tumors can be successfully managed with surgery, a subset require chemotherapy for residual and recurrent disease. The benefit of chemotherapy in this population, however, remains controversial. There is therefore interest in the development of more tolerable and effective treatment options for advanced ovarian granulosa cell tumors. We report the use of immunohistochemistry to investigate how biomarkers could inform clinical trials in granulosa cell tumors with an emphasis on emerging androgen antagonistic, immunotherapeutic, and anti-angiogenic approaches. METHODS: Immunohistochemistry for androgen receptor, the immune markers programmed cell death ligand 1, indoleamine-2,3 dioxygenase, and cluster of differentiation 8, and the vascular marker cluster of differentiation 31 were evaluated on formalin-fixed paraffin-embedded whole tissue sections from 29 cases of adult-type granulosa cell tumors. Results were evaluated with clinicopathologic variables including recurrence. RESULTS: 59% of granulosa cell tumors were androgen receptor-positive, suggesting a potential role for anti-androgen therapy in this tumor type. In contrast, the targetable immune modulatory molecules programmed cell death ligand 1 and indoleamine-2,3 dioxygenase were scarcely expressed, with no cases showing tumorous programmed cell death ligand 1 and a single case demonstrating very focal tumorous indoleamine-2,3 dioxygenase staining. A minority of cases expressed programmed cell death ligand 1 in occasional tumor-associated macrophages and indoleamine-2,3 dioxygenase in peritumoral vessels. Tumor-infiltrating cytotoxic T cells were also scarce in granulosa cell tumors, arguing against a significant role for immunotherapy in the absence of additional immunostimulation. Cluster of differentiation 31 immunostaining revealed a range of vascular densities across granulosa cell tumors, and future studies evaluating the role of vascular density as a predictor of response to angiogenesis inhibition are warranted. None of the biomarkers investigated were significantly correlated with recurrence, and the only clinicopathologic feature significantly correlated with outcome was stage at presentation. CONCLUSIONS: Biomarker data suggest that many ovarian granulosa cell tumors could be candidates for anti-androgen therapy, while the potential role for immunotherapy appears more limited. Vascular density could be useful for identifying optimal candidates for angiogenesis inhibition. Incorporation of these biomarkers into clinical trials could help optimize patient selection.