Benign TdT-positive cells in pediatric and adult lymph nodes: a potential diagnostic pitfall

Benign TdT-positive cells have been documented in a variety of non-hematopoietic tissues. Scant data are however available on their presence in non-neoplastic lymph nodes. This study is aimed to: (i) characterize the presence/distribution of benign TdT-positive cells in pediatric and adult reactive lymph nodes; (ii) define the phenotype and nature of such elements. This retrospective study considered 141 reactive lymph nodes from pediatric and adult patients without history of neoplastic disease. TdT-positive cells were characterized by immunohistochemical and morphometric analyses and their presence was correlated with the clinical-pathological features. The nature of TdT-positive cells was investigated by: (i) double immunostaining for early lymphoid cell markers; and (ii) assessment of TdT expression in fetal lymph nodes. Sparse TdT-positive cells were documented in all pediatric cases and in most (76%) adult lymph nodes. TdT-positive cell density was higher in children than adults (15.9/mm2 versus 8.6/mm2; P<.05). TdT positivity did not correlate with any clinical and histological parameter and double immunostaining disclosed a phenotype compatible with early lymphoid precursors (positivity for CD34, CD10 and variable expression of CD7). A very high TdT-positive cell density (802.4/mm2) was reported in all fetal lymph nodes. In conclusion, TdT-positive cells are a common finding in pediatric and adult lymph nodes. The interstitial distribution and low number of such cells allows for the differential diagnosis with precursor lymphoid neoplasms. The high density in fetal lymph nodes and the phenotype of such cells suggest their belonging to an immature lymphoid subset gradually decreasing with age

Multicentric B-cell lymphoma in a pygmy goat

A six-year-old, male pygmy goat was referred with a sudden onset of peripheral lymphadenopathy, which initially started as enlarged inguinal lymph nodes. Clinical examination showed swollen retropharyngeal, prescapular and inguinal lymph nodes. Serologic testing for bovine leukemia, caprine arthritis-encephalitis virus and caseous lymphadenitis was negative. Fine needle aspirates of the prescapular lymph nodes were taken and revealed multiple, large lymphoblastic cells on cytology. Because of the poor prognosis and clinical deterioration, the animal was euthanized. Full necropsy was performed and showed generalized lymphadenopathy. Further histological and immunohistochemical investigation of the lymph nodes characterized this neoplasia as a multicentric large B-cell lymphoma

Enrichment of innate lymphoid cell populations in gingival tissue

Innate lymphoid cells (ILCs) are a population of lymphocytes that act as the first line of immunologic defense at mucosal surfaces. The ILC family in the skin, lungs, and gastrointestinal tissues has been investigated, and there are reports of individual subsets of ILCs in the oral tissues. We sought to investigate the whole ILC population (group 1, 2, and 3 subsets) in the murine gingivae and the lymph nodes draining the oral cavity. We show that ILCs made up a greater proportion of the whole CD45+ lymphocyte population in the murine gingivae (0.356% ± 0.039%) as compared with the proportion of ILCs in the draining lymph nodes (0.158% ± 0.005%). Cytokine profiling of the ILC populations demonstrated different proportions of ILC subsets in the murine gingivae versus the regional lymph nodes. The majority of ILCs in the draining lymph nodes expressed IL-5, whereas there were equal proportions of IFN-γ- and IL-5 expressing ILCs in the oral mucosa. The percentage of IL-17+ ILCs was comparable between the murine gingivae and the oral draining lymph nodes. These data suggest an enrichment of ILCs in the murine gingivae, and these ILCs reflect a cytokine profile discrepant to that of the local draining lymph nodes. These studies indicate diversity and enrichment of ILCs at the oral mucosal surface. The function of ILCs in the oral cavity remains to be determined; here, we provide a premise of ILC populations that merits future consideration in investigations of mouse models and human tissues

Lymph Nodes

Histology blog entry for September 18, 2008 about lymph nodes

Histopathology report on colon cancer specimens; measuring surgical quality, an increasing stress for surgeons

Introduction. Improving the quality of surgical resections by evaluating surgical specimens is probably the most important feedback a surgeon can receive. Moreover, prognosis of patients with colon cancer is based on achieving appropriate resection margins and assessment of lymph node status. For these reasons we aim to provide a retrospective analysis on colon cancer specimens operated by a single surgical team. Materials and Methods. 88 patients operated between 2013 and 2016 were included in the study. Data were gathered prospectively and assessed by multivariate analysis for the main variables (age, gender, tumor staging, specimen length, distance to closest resection margin, number of lymph nodes, and number of positive lymph nodes). Results. The mean number of lymph nodes excised was 31,9, with more after right colectomies (39.6) than after left colonic resections (29.1). The average specimen length was 29.2cm after right colectomies, 35.6cm after left hemicolectomies and 18cm after segmental colectomies. There was a significant correlation between the number of lymph nodes, specimen length, and age of patients. Conclusion. Lymph node status is correlated with specimen length and age. The standard of 12 lymph nodes was achieved and surpassed, being comparable to the benchmark literature. Standards on colon resections need to be reevaluated as many surgeons are pressured by quality measurements which do not always reflect sound oncologic principles

Experimental studies of the endolymphatic radiotherapy

By injecting 131I-Lipiodol into lymphatics of the dorsum of dog feet, the distribution of 13JI in the lymph nodes and other principal organs as well as its histological effect were studied periodically after the injection for the period of two months. The characteristic feature of J3JI distribution was the fact that J31I was accumulated into lymph nodes markedly higher than in any other organs and it was retained there over a long period of time. Histological examinations of the lymph nodes revealed a marked lymphocytopenia, the loss of germinal center, practically complete loss of lymphoid elements already 5 days after injection, and marked fibrosis. In the lung a considerable J3JI·distribution could be seen in early stage:, but with lapse of time it decreased rapidly. The distribution in other organs such as liver, spleen, bone marrow, kidney, ureter, bladder, thyroid gland, pancreas, testicles and small and large intestines was negligible in amount, and any specific histologic effect of irradiation could not be recognized in these organs including the lung. From these results, the authors concluded that 131I-Lipiodol has a selective activity on lymph nodes by injecting it via lymphatics and it is a safe method in clinical application to treat the patients bearing malignant lymphoma or metastatic lymph nodes.</p

Changes in the Cell Squad of Iliac Lymph Nodes of White Rats in Case of Longterm Influence of Nalbufin

The article presents data on the change in the cellular composition of the lymph nodes of the white rats, males of reproductive age, who received intramuscular opioid analgesics - nalbuphine every day for six weeks. The weekly dose of nalbuphine was gradually increased, creating a model of physical opioid dependence according to the patent of Ukraine No. 76564 U. All experimental animals were divided into 8 groups.Morphometric method was used to determine the relative number of cells of the lymphoid series - small, medium and large lymphocytes, blasts and plasmocytes in the cloak zone and the embryonic center of the secondary lymphoid nodes and brain strands of the lymph nodes. Morphometric studies were performed using a system of visual analysis of histological preparations.It was established that nalbuphine in the lymph nodes causes reactive and destructive changes: the number of large lymphocytes increases in all structural components of the lymph node with a maximum after 4 weeks, respectively, the relative number of small lymphocytes decreases in the nucleus centers and brain tracts, the relative number of plasmocytes in the brain strains increases sharply . In all structural components of the lymph nodes hemocapillaries and venules are dilated and full-blooded, around vascular edema and partial damage to the walls of the microvessels.One week after the discontinuation of nalbuphine, the relative number of lymphoid cells in the structural components of the lymph nodes does not return to the indicators of intact animals, no reversible changes are noted

Lymph nodes go with the flow

In this issue, Bovay et al. (https://doi.org/10.1084/jem.20180217) invoke a compelling model of interplay between the venous and lymphatic vasculature in regulating the developmental genesis and early expansion of LNs. This work supports an emerging model that lymph-venous crosstalk supports LN functionality at all stages

Tracking the source of the hepatitis B virus-specific CD8 T cells during lamivudine treatment

Lamivudine treatment in chronic hepatitis B leads to the reconstitution of virus-specific T cells in the circulation, but it is not clear whether this is the preferential result of T cell efflux from the liver or lymph nodes. To address this question, the frequency and function of liver-, lymph node-, and blood-derived hepatitis B virus (HBV)-specific CD8 T cells were analyzed in patients treated with lamivudine and undergoing liver transplantation. HBV-specific CD8 T cells, identified in portal lymph nodes, were able to expand in vitro after antigen-specific stimulation and displayed a heterogeneous profile of cytokine production. These findings suggest that the peripherally reconstituted HBV-specific CD8 T cells can originate from precursor cells within lymph nodes

Optimal MRI sequences for 68Ga-PSMA-11 PET/MRI in evaluation of biochemically recurrent prostate cancer.

BackgroundPET/MRI can be used for the detection of disease in biochemical recurrence (BCR) patients imaged with 68Ga-PSMA-11 PET. This study was designed to determine the optimal MRI sequences to localize positive findings on 68Ga-PSMA-11 PET of patients with BCR after definitive therapy. Fifty-five consecutive prostate cancer patients with BCR imaged with 68Ga-PSMA-11 3.0T PET/MRI were retrospectively analyzed. Mean PSA was 7.9&nbsp;±&nbsp;12.9&nbsp;ng/ml, and mean PSA doubling time was 7.1&nbsp;±&nbsp;6.6&nbsp;months. Detection rates of anatomic correlates for prostate-specific membrane antigen (PSMA)-positive foci were evaluated on small field of view (FOV) T2, T1 post-contrast, and diffusion-weighted images. For prostate bed recurrences, the detection rate of dynamic contrast-enhanced (DCE) imaging for PSMA-positive foci was evaluated. Finally, the detection sensitivity for PSMA-avid foci on 3- and 8-min PET acquisitions was compared.ResultsPSMA-positive foci were detected in 89.1% (49/55) of patients evaluated. Small FOV T2 performed best for lymph nodes and detected correlates for all PSMA-avid lymph nodes. DCE imaging performed the best for suspected prostate bed recurrence, detecting correlates for 87.5% (14/16) of PSMA-positive prostate bed foci. The 8-min PET acquisition performed better than the 3-min acquisition for lymph nodes smaller than 1&nbsp;cm, detecting 100% (57/57) of lymph nodes less than 1&nbsp;cm, compared to 78.9% (45/57) for the 3-min acquisition.ConclusionPSMA PET/MRI performed well for the detection of sites of suspected recurrent disease in patients with BCR. Of the MRI sequences obtained for localization, small FOV T2 images detected the greatest proportion of PSMA-positive abdominopelvic lymph nodes and DCE imaging detected the greatest proportion of PSMA-positive prostate bed foci. The 8-min PET acquisition was superior to the 3&nbsp;min acquisition for detection of small lymph nodes