Julio A. Diaz-Perez

EBV-positive diffuse large B-cell lymphoma of the elderly is an aggressive post-germinal center B-cell neoplasm characterized by prominent nuclear factor-kB activation.

Here, we report a retrospective series of 47 EBV-positive diffuse large B-cell lymphoma associated with advanced age. Histopathology allowed to the identification of different histological patterns: cases with polymorphic diffuse large B-cell lymphoma (29 cases), Hodgkin-like (8 cases) and polymorphic lymphoproliferative disorder-like (9 cases) patterns. One case was purely monomorphic diffuse large B-cell lymphoma. We show that this lymphoma type is a neoplasm with prominent classical and alternative nuclear factor-kB pathway activation in neoplastic cells (79% of the cases showed nuclear staining for p105/p50, 74% for p100/p52 and 63% for both proteins), with higher frequency than that observed in a control series of EBV-negative diffuse large B-cell lymphoma (χ2 <0.001). Most cases showed an activated phenotype (95% non-germinal center (Hans algorithm); 78% activated B cell (Choi algorithm)). Clonality testing demonstrated IgH and/or K/Kde/L monoclonal rearrangements in 64% of cases and clonal T-cell populations in 24% of cases. C-MYC (1 case), BCL6 (2 cases) or IgH (3 cases) translocations were detected by FISH in 18% cases. These tumors had a poor overall survival and progression-free survival (the estimated 2-year overall survival was 40±10% and the estimated 2-year progression-free survival was 36±9%). Thus, alternative therapies, based on the tumor biology, need to be tested in patients with EBV-positive diffuse large B-cell lymphoma of the elderly.

TCR-γ expression in primary cutaneous T-cell lymphomas.

Primary cutaneous &ggr;&dgr; T-cell lymphomas (PCGD-TCLs) are considered a subgroup of aggressive cytotoxic T-cell lymphomas (CTCLs). We have taken advantage of a new, commercially available antibody that recognizes the T-cell receptor-&ggr; (TCR-&ggr;) subunit of the TCR in paraffin-embedded tissue. We have analyzed a series of 146 primary cutaneous T-cell lymphomas received for consultation or a second opinion in the CNIO Pathology Department. Cases were classified according to the World Health Organization 2008 classification as mycosis fungoides (MF; n=96), PCGD-TCLs (n=5), pagetoid reticulosis (n=6), CD30+ primary cutaneous anaplastic large cell lymphomas (n=5), primary cutaneous CD8+ aggressive epidermotropic CTCLs (n=3), primary cutaneous CTCL, not otherwise specified (n=4), and extranodal nasal-type NK/T-cell lymphomas primarily affecting the skin or subcutaneous tissue (n=11). Sixteen cases of the newly named lymphomatoid papulosis type D (LyP-D; n=16) were also included. In those cases positive for TCR-&ggr;, a further panel of 13 antibodies was used for analysis, including TIA-1, granzyme B, and perforin. Clinical and follow-up data were recorded in all cases. Twelve cases (8.2%) were positive for TCR-&ggr;, including 5 PCGD-TCLs, 2 MFs, and 5 LyP-Ds. All 5 PCGD-TCL patients and 1 MF patient died of the disease, whereas the other MF patient and all those with LyP-D were alive. All cases expressed cytotoxic markers, were frequently CD3+/CD8+, and tended to lose CD5 and CD7 expressions. Eight of 12 and 5 of 11 cases were CD30+ and CD56+, respectively. Interestingly, 5/12 TCR-&ggr;-positive cases also expressed TCR-BF1. All cases analyzed were negative for Epstein-Barr virus–encoded RNA. In conclusion, TCR-&ggr; expression seems to be rare and is confined to cytotoxic primary cutaneous TCLs. Nevertheless, its expression is not exclusive to PCGD-TCLs, as TCR-&ggr; protein can be found in other CTCLs. Moreover, its expression does not seem to be associated with bad prognosis by itself, as it can be found in cases with good and bad outcomes.

Matrix-Metalloproteinases in Head and Neck Carcinoma–Cancer Genome Atlas Analysis and Fluorescence Imaging in Mice

Objective (1) Obtain matrix-metalloproteinase (MMP) expression profiles for head and neck squamous cell carcinoma (HNSCC) specimens from the Cancer Genomic Atlas (TCGA). (2) Demonstrate HNSCC imaging using MMP-cleavable, fluorescently labeled ratiometric activatable cell-penetrating peptide (RACPP). Study Design Retrospective human cohort study; prospective animal study. Setting Translational research laboratory. Subjects and Methods Patient clinical data and mRNA expression levels of MMP genes were downloaded from TCGA data portal. RACPP provides complementary ratiometric fluorescent contrast (increased Cy5 and decreased Cy7 intensities) when cleaved by MMP2/9. HNSCC–tumor bearing mice were imaged in vivo after RACPP injection. Histology was evaluated by a pathologist blinded to experimental conditions. Zymography confirmed MMP-2/9 activity in xenografts. RACPP was applied to homogenized human HNSCC specimens, and ratiometric fluorescent signal was measured on a microplate reader for ex vivo analysis. Results Expression of multiple MMPs including MMP2/9 is greater in patient HNSCC tumors than matched control tissue. In patients with human papilloma virus positive (HPV+) tumors, higher MMP2 and MMP14 expression correlates with worse 5-year survival. Orthotopic tongue HNSCC xenografts showed excellent ratiometric fluorescent labeling with MMP2/9-cleavable RACPP (sensitivity = 95.4%, specificity = 95.0%). Fluorescence ratios were greater in areas of higher tumor burden (P < .03), which is useful for intraoperative margin assessment. Ex vivo, human HNSCC specimens showed greater cleavage of RACPP when compared to control tissue (P = .009). Conclusions Human HNSCC tumors show increased mRNA expression of multiple MMPs including MMP2/9. We used RACPP, a ratiometric fluorescence assay of MMP2/9 activity, to show improved occult tumor identification and margin clearance. Ex vivo assays using RACPP in biopsy specimens may identify patients who will benefit from intraoperative RACPP use.

Surgical molecular navigation with ratiometric activatable cell penetrating peptide for intraoperative identification and resection of small salivary gland cancers

We evaluated the use of intraoperative fluorescence guidance by enzymatically cleavable ratiometric activatable cell‐penetrating peptide (RACPPPLGC(Me)AG) containing Cy5 as a fluorescent donor and Cy7 as a fluorescent acceptor for salivary gland cancer surgery in a mouse model.

Evaluation of a teaching strategy based on integration of clinical subjects, virtual autopsy, pathology museum, and digital microscopy for medical students

Background: Learning pathology is fundamental for a successful medical practice. In recent years, medical education has undergone a profound transformation toward the development of an integrated curriculum incorporating both basic science and clinical material. Simultaneously, there has been a shift from a magisterial teaching approach to one centered around problem-based learning. Now-a-days, informatics tools are expected to help better implement these strategies. Aim: We applied and evaluated a new teaching method based on an active combination of clinical problems, gross pathology, histopathology, and autopsy pathology, all given through informatics tools, to teach a group of medical students at the Universidad de Santander, Colombia. Design: Ninety-four medical students were followed in two consecutive semesters. Students were randomized to receive teaching either through traditional methodology or through the new integrated approach. Results: There was no significant difference between the intervention group and the control group at baseline. At the end of the study, the scores in the intervention group were significantly higher compared to the control group (3.91/5.0 vs. 3.33/5.0, P = 0.0008). Students and tutors endorsed the benefits of the integrated approach. Participants were very satisfied with this training approach and rated the program an 8.7 out of 10, on average. Conclusion: This study confirms that an integrated curriculum utilizing informatics systems provides an excellent opportunity to associate pathology with clinical medicine early in training of medical students. This can be possible with the use of virtual microscopy and digital imaging.

Glioblastoma Metastasis to Parotid Gland and Neck Lymph Nodes: Fine-Needle Aspiration Cytology with Histopathologic Correlation

Glioblastoma (GBM) is one of the most highly aggressive neoplasms of the central nervous system. Extra-cranial metastases in GBM are rare. Here we present the case of a 26-year-old man with extra-cranial metastasis of a frontal lobe GBM to the parotid gland, cervical lymph nodes, and bones, with initial diagnosis made by fine needle aspiration cytology (FNAC) of the parotid gland. FNAC is a reliable technique in the study of primary and secondary parotid gland neoplasms, allowing a presumptive diagnosis in difficult cases. We correlate the cytologic, histopathologic, and immunohistochemical findings in this case and discuss previous literature reports.

Primary malignant solitary fibrous tumor/hemangiopericytoma of the parotid gland

Solitary fibrous tumor (SFT) was first described in the pleura by Lietaud in 1767; later in 1870, Wagner described the localized nature of this type of tumor and Klemperer and Rabin classified pleural tumors into two types: diffuse mesotheliomas and localized mesotheliomas. Recent years have seen the redefinition of this neoplasm, due to better technology; it is now proven that this neoplasm may have multiple different extrapleural origins including the head and neck regions. This diversity of locations is related to the particular mesenchymal histogenesis of SFT which allows its development from very unusual sites such as the salivary glands (SGs). In this particular site, this neoplasm is very infrequent and most of reported cases refer to benign disease, with just one case informed so far of primary malignant SFT.

Primary Yolk Sac Tumor of the Urachus

Introduction. Neoplasms originating from the urachus are rare. The most common urachal malignancy is adenocarcinoma, whereas extragonadal germ cell tumors, primarily of the urachus, are an extremely rare finding. Objective. To describe a primary yolk sac tumor (YST) of the urachus in an adult. Case report. A 44-year-old woman presented with 6 months of pelvic pain associated with a sensation of progressive mass growth. At the time of tumor resection, the tumor was found to be attached by a pedicle to the dome of the bladder, with no injury to the adjacent organs. Pathological study showed a neoplasm with epithelioid cells, pseudocysts, a myxomatous background, and Schiller-Duval body formations. Immunohistochemistry stains showed positivity to AE1/AE3, α-1-fetoprotein, and α-1-antitrypsin and negativity to other markers. Conclusion. An unusual case of a YST in the urachus is presented. This is the first reported adult case based on the authors’ bibliographic search.

Preclinical immunoPET/CT imaging using Zr-89-labeled anti-PD-L1 monoclonal antibody for assessing radiation-induced PD-L1 upregulation in head and neck cancer and melanoma

ABSTRACT Radiation therapy (RT) can induce upregulation of programmed death ligand 1 (PD-L1) on tumor cells or myeloid cells, which may affect response to PD-1-based immunotherapy. PD-L1 upregulation during RT is a dynamic process that has been difficult to monitor during treatment. The aim of this study was to evaluate the RT-induced PD-L1 upregulation in the tumor and its microenvironment using immunoPET/CT imaging of two syngeneic murine tumor models (HPV+ head and neck squamous cell carcinoma (HNSCC) or B16F10 melanoma). Tumors were established in two locations per mouse (neck and flank), and fractionated RT (2 Gy × 4 or 2 Gy × 10) was delivered only to the neck tumor, alone or during anti-PD-1 mAb immunotherapy. PD-L1 expression was measured by PET/CT imaging using Zr-89 labeled anti-mouse PD-L1 mAb, and results were validated by flow cytometry. PET/CT imaging demonstrated significantly increased tracer uptake in irradiated neck tumors compared with non-irradiated flank tumors. Ex vivo analysis by biodistribution and flow cytometry validated PD-L1 upregulation specifically in irradiated tumors. In the HNSCC model, RT-induced PD-L1 upregulation was only observed after 2 Gy × 10 fractionated RT, while in the B16F10 model upregulation of PD-L1 occurred after 2 Gy × 4 fractionated RT. Fractionated RT, but not anti-PD-1 therapy, upregulated PD-L1 expression on tumor and infiltrating inflammatory cells in murine models, which could be non-invasively monitored by immunoPET/CT imaging using Zr-89 labeled anti-mouse PD-L1 mAb, and differentially identified anti-PD-1 responsive as well as selectively irradiated tumors in vivo.

Molecular targeting of papillary thyroid carcinoma with fluorescently labeled ratiometric activatable cell penetrating peptides in a transgenic murine model

Molecularly targeted fluorescent molecules may help detect tumors that are unseen by traditional white‐light surgical techniques. We sought to evaluate a fluorescent ratiometric activatable cell penetrating peptide (RACPP) for tumor detection in a transgenic model of PTC.