Anatomomopathological and immunohistochemical analyses of the spleen and lymph node of dogs seropositives for leishmaniasis in serological tests

Canine leishmaniasis (CanL) is a zoonosis caused by the protozoan of the species Leishmania infantum. The spleen and lymph nodes undergo morphological changes during CanL. This research aimed to perform an anatomopathological and immunohistochemical study of these organs in dogs reactive to leishmaniasis in the Dual-path Platform chromatographic immunoassay (DPP®) and Enzyme Immunoabsorption Assay (ELISA). Twenty-seven dogs were evaluated for anatomopathological examination with 92.6% showing changes at gross evaluation, specially splenomegaly and lymphadenomegaly. All dogs showed changes in the spleen unrelated to the parasitic load, with granulomatous splenitis being the most severe change. Diffuse cortical and paracortical hyperplasia, and hyperplasia and hypertrophy of the medullary cords were observed in the lymph node. Amastigote forms of Leishmania spp. were found in the spleen and lymph node at histopathological and immunohistochemical evaluations, with good agreement between these evaluations (k = 0.55, p = 0.00124), but no difference was observed in the parasitic intensity of these organs at immunohistochemistry (p = 0.23). It was concluded that spleen and lymph node from dogs reactive to leishmaniasis on the DPP® and ELISA tests show histomorphological changes resulting from the disease, independent to the parasitic load, as well as these organs show similar parasitic load at immunohistochemical test.

Can the lymph node reactivity pattern in the pN0 neck analysis provide any additional prognostic information in patients with laryngeal squamous cell carcinoma?

ABSTRACT Objective: To evaluate the influence of lymph node reactivity on recurrence and survival rates in a population of pT3 or pT4 pN0 patients with laryngeal squamous cell carcinoma. Methods: Between 2002 and 2005, 105 patients with LSSC underwent total laryngectomy with bilateral selective neck dissection including levels II, III and IV. Most (69) received PO radiotherapy. All pathological specimens were either pT3 or pT4, and all necks were pN0. All lymph nodes were analyzed and their reactivity status were classified as the following four patterns: follicular hyperplasia associated with humoral response, paracortical hyperplasia associated with cellular response, sinus histiocytosis with no association with specific immune response, or normal lymph node. Only the first two patterns were considered stimulated, whereas the last two were considered non-stimulated. The most prevalent pattern in a particular neck specimen was considered for the analysis of recurrence and survival. Results: The total number of lymph nodes studied was 3,648, with an average of 34.7 lymph nodes/neck specimens. The most frequent lymph node reactivity patterns were sinusal histiocytosis (50 cases), paracortical hyperplasia (35 cases), and follicular hyperplasia (20 cases). There was no statistical association of these individual patterns with recurrence rate (p = 0.98) or mortality (p = 0.49). However, there was a statistically significant association between paracortical hyperplasia pattern (related to cellular lymph node immunity) and improved five-year survival (76 versus 60%; log-rank = 0.05). Conclusions: There was a positive correlation between stimulated cellular lymph node pattern and improved 5-year survival rate in patients with pN0 laryngeal squamous cell carcinoma, suggesting the indication of adjuvant treatment for those individuals with decreased immune response, even in the absence of pathologic metastases detected by the usual methods.

Evaluation of lymph node reactivity in differentiated thyroid carcinoma

CONTEXT: The development of metastases is the most notable characteristic of malignant neoplasias. The filter function of lymph nodes, which led to the idea of including lymphatic treatment in surgical management of metastases. OBJECTIVES: To evaluate morphological alterations in neck nodes in the presence of differentiated thyroid carcinoma (DTC): hyperplasia, histiocytosis, desmoplasia, capsular rupture, necrosis and their relation to the biological behavior of these neoplasias. DESIGN: Retrospective study. SETTING: University referral unit. PARTICIPANTS: 98 DTC patients, from 1977 to 1992, 18 cases were selected for histological analyses, of which 14 were female and 4 males, with an average age of 50.2 years. From these cases, 290 lymph nodes were analyzed (81 with metastasis), with an average of 16 lymph nodes/patient. MAIN MEASUREMENTS: Morphological evaluation of paraffin cuts stained by HE was done using an optical microscope, looking for presence of the abovementioned neoplasias and their UICC-TNM (1997) staging. RESULTS: Sinus histiocytosis was 2.4 times more frequent in the absence of lymph node metastasis (pNo). Disease recurrence occurred in 5 patients, all of whom were more than 40 years old (p= 0.24) and 4 of whom had necrosis (p= 0.02). Six patients with predominance of paracortical hyperplasia (p= 0.02) did not show as much relapse into disease as those with less than 6 metastasis lymph nodes (p= 0.009). CONCLUSIONS: The presence of paracortical hyperplasia is associated with a better prognosis. The existence of necrosis or metastasis in more than 6 lymph nodes in patients over 40 years of age is related to higher risk of relapse of disease in DTC.