Evaluation of lymph node reactivity in differentiated thyroid carcinoma

Area of Science:

• Oncology
• Pathology
• Surgical Oncology

Background:

• Metastasis is a key feature of malignant neoplasias.
• Lymph node function in filtering metastases informed the inclusion of lymphatic treatment in surgical management.
• Understanding lymph node morphology is crucial for predicting cancer behavior.

Purpose of the Study:

• To investigate morphological changes in neck lymph nodes associated with differentiated thyroid carcinoma (DTC).
• To correlate these morphological alterations (hyperplasia, histiocytosis, desmoplasia, capsular rupture, necrosis) with the biological behavior and prognosis of DTC.
• To identify prognostic indicators for DTC recurrence based on lymph node pathology.

Main Methods:

• Retrospective study conducted at a university referral unit.
• Histological analysis of 290 lymph nodes from 18 DTC patients (14 female, 4 male, average age 50.2 years) diagnosed between 1977 and 1992.
• Morphological evaluation of HE-stained paraffin sections using an optical microscope, assessing for specific features and UICC-TNM staging.

Main Results:

• Sinus histiocytosis was more frequent in lymph nodes without metastasis.
• Disease recurrence occurred in 5 patients, all over 40 years old, with 4 showing necrosis (p=0.02).
• Patients with predominant paracortical hyperplasia (p=0.02) had less disease relapse compared to those with fewer than 6 metastatic lymph nodes (p=0.009).

Conclusions:

• Paracortical hyperplasia in neck lymph nodes is linked to a favorable prognosis in DTC.
• The presence of necrosis or metastasis in over 6 lymph nodes, particularly in patients older than 40, indicates an elevated risk of disease relapse.
• Morphological assessment of lymph nodes can aid in predicting DTC outcomes.