# Pathological Findings, Clinical Characteristics, and Outcomes of Thyroid Lymphomas: A Single Tertiary Care Hospital Experience

## TL;DR

This study examines 12 cases of thyroid lymphoma in Saudi Arabia, finding that most cases were a type of B-cell lymphoma and often occurred with thyroiditis.

## Contribution

The study provides new clinical and pathological insights into primary thyroid lymphoma from a single tertiary hospital in Saudi Arabia.

## Key findings

- Diffuse large B-cell lymphoma was the most common subtype (66.7%).
- Most patients had thyroiditis and cervical/mediastinal lymph node involvement.

## Abstract

Background: Primary thyroid lymphoma (PTL) is a rare malignancy accounting for a small percentage of thyroid cancers and extra-nodal lymphomas. Treatment and prognosis depend on the histologic type and stage. Local studies and international reviews highlight the predominance of B-cell non-Hodgkin's lymphomas. This study aims to identify the subtypes, clinical characteristics, and outcomes of PTL in a tertiary care hospital.

Methodology: This study presents a case series of 12 patients diagnosed with PTL between 2010 and 2024 at King Abdulaziz Medical City (KAMC) in Riyadh, Saudi Arabia. Descriptive statistics were used to summarize cohort characteristics. Continuous variables were presented as mean and standard deviation. Categorical variables were represented as frequencies and percentages.

Results: Among the 12 patients included with PTL, histopathological examination identified 66.7% with diffuse large B-cell lymphoma (DLBCL), followed by mucosa-associated lymphoid tissue (MALT) lymphoma in 16.7% of cases. Half of the cases had thyroiditis, and the majority presented with neck swelling and compressive symptoms. Most had lymph node involvement (66.67%).

Conclusion: In summary, this study provides an exclusive insight into the pathological findings, clinical characteristics, and outcomes of PTL in a tertiary care hospital. PTL is a rare malignancy; however, it is a potential diagnosis when encountering an enlarged neck mass, especially with Hashimoto’s thyroiditis. Overall, DLBCL was the most common type identified. The majority of the cases had cervical/mediastinal lymph node involvement and thyroiditis.