Posttransplant lymphoproliferative disorders (PTLDs) represent a broad spectrum of lymphoid proliferations, frequently associated with Epstein-Barr virus (EBV) infection. The molecular profile of pediatric monomorphic PTLDs (mPTLDs) has not been elucidated, and it is unknown whether they display similar genetic features as their counterpart in adult and immunocompetent (IMC) pediatric patients. In this study, we investigated 31 cases of pediatric mPTLD after solid organ transplantation, including 24 diffuse large B-cell lymphomas (DLBCLs), mostly classified as activated B cell, and 7 cases of Burkitt lymphoma (BL), 93% of which were EBV positive. We performed an integrated molecular approach, including fluorescence in situ hybridization, targeted gene sequencing, and copy number (CN) arrays. Overall, PTLD-BL carried mutations in MYC, ID3, DDX3X, ARID1A, or CCND3 resembling IMC-BL, higher mutational burden than PTLD-DLBCL, and lesser CN alterations than IMC-BL. PTLD-DLBCL showed a very heterogeneous genomic profile with fewer mutations and CN alterations than IMC-DLBCL. Epigenetic modifiers and genes of the Notch pathway were the most recurrently mutated in PTLD-DLBCL (both 28%). Mutations in cell cycle and Notch pathways correlated with a worse outcome. All 7 patients with PTLD-BL were alive after treatment with pediatric B-cell non-Hodgkin lymphoma protocols, whereas 54% of patients with DLBCL were cured with immunosuppression reduction, rituximab, and/or low-dose chemotherapy. These findings highlight the low complexity of pediatric PTLD-DLBCL, their good response to low-intensity treatment, and the shared pathogenesis between PTLD-BL and EBV-positive IMC-BL. We also suggest new potential parameters that could help in the diagnosis and the design of better therapeutic strategies for these patients.

Recently, there have been reports of what could be a new lymphoproliferative entity: breast implant-associated Epstein–Barr virus positive (EBV+) diffuse large B-cell lymphoma (EBV+ BIA-DLBCL). The new World Health Organization classification has categorized it as fibrin-associated large B-cell lymphomas (FA-LBCLs); therefore, it could be referred to as breast implant-associated fibrin-associated large B-cell lymphomas (BIA-FA-LBCLs). Although the association between breast implants and lymphomas has been known since the mid-1990s, it has been almost exclusively breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). Here, we describe the first case of BIA-FA-LBCL at our center, with a literature review of the clinical features, diagnosis and treatment approach of this lymphoma. We also explore the differential diagnosis of BIA-FA-LBCL, highlighting the diagnostic challenges and the reasons that have led these lymphomas to being labeled as a new face of FA-LBCL.

García‐Fernández E, De Diego J I, Collantes‐Bellido E, Mendiola M, Prim M P, Pérez‐Fernández E, Miguel‐Martín M, Nistal M & Hardisson D (2011) Histopathology58, 368–376 Aurora B kinase expression in laryngeal squamous cell carcinoma and its prognostic implicationsAims:  To investigate the clinical and prognostic significance of Aurora B in laryngeal squamous cell carcinomas (LSCC).Methods and results:  Aurora B protein expression was analysed in 259 LSCC. The proliferation index (Ki67) and the expression of other cell cycle control proteins, such as Aurora A, survivin and p53 was also determined. Aurora B was highly expressed in 55.4% of LSCC. High Aurora B expression levels were correlated with tumour recurrence (P = 0.01), death from disease (P = 0.05) and decreased disease‐free survival (P = 0.013) and overall survival (P = 0.04). Survivin expression was neither associated with clinicopathological characteristics nor with survival. However, survivin expression in the nucleus paralleled Aurora B expression (P = 0.014). Aurora A expression was associated significantly with increased tumour grade (P = 0.008). Multivariate analysis indicated that Aurora B was an independent predictor for LSCC‐specific disease‐free survival [hazard ratio (HR), 2.10; 95% confidence interval (95% CI), 1.25–3.52 (P = 0.005)] and overall survival [HR, 1.91; 95% CI 1.01–3.34 (P = 0.023)].Conclusions:  Aurora B may be a novel prognostic biomarker for LSCC and a potential therapeutic target in this type of tumour.

Fetal gonadoblastoid testicular dysplasia (FGTD) is an extremely rare lesion, which, in its original description, appeared in association with hydrops fetalis and other malformations. Its phenotype strongly resembles gonadoblastoma, although in contrast with that rare tumor, FGTD is not associated with the intersexual states or gonadal dysgenesis that accompany such neoplasm. Two reports described an association of FGTD and a morphologically similar lesion with Walker-Warburg syndrome. However, we have not confirmed such an observation, although a nonspecific muscle disorder was found in one of the examples we describe in this article. Here we study 2 additional cases, providing a detailed topographical, histomorphological, and immunophenotypical analysis. A review of all 5 previously described cases is conducted. The features of this lesion support the notion that a focal defect in testicular development is its most likely pathogenesis.