[A retrospective analysis of 12 cases of primary thyroid lymphoma]

To discuss the clinical characteristics and diagnostic and therapeutic considerations of primary thyroid lymphoma (PTL) by reviewing PTL cases.

In the study, 12 cases of PTL diagnosed and treated in Peking University First Hospital between January 1995 and September 2015 were identified. The clinical characteristics, management experiences and prognosis of these cases were reviewed retrospectively.

A total of 12 PTL patients (four males and eight females) were collected, with an average age of 63 years (42 to 81 years) at the time of diagnosis. The average time to clarify diagnosis was 5 months (0.5 to 24 months). Eleven patients presented with a rapidly growing neck mass and visited surgical department, except one complained of coughing and suffocated. Seven patients were hypothyroid, and four were euthyroid at the time of diagnosis. In sonography of 11 cases, nine showed bilateral nodules, with an average diameter of 3.87 cm. Pathologic diagnosis of non-Hodgkin's lymphoma was confirmed in all the 12 cases by means of partial thyroidectomy (four) or core needle biopsy (eight). The pathological subtypes were diffuse large B cell lymphoma in nine patients, mucosa-associated lymphoid tissue lymphoma (MALToma) in two, and small B cell lymphoma in the other one patient. Five patients were concomitant with Hashimoto's thyroiditis. Eleven patients received chemotherapy. Only one patient did not have any further treatment after operation due to an inertia type of tumor. The median overall survival time was 24 months (1-117 months), three patients died. Among the patients who survived, seven completed chemotherapy without disease progression, one MALToma case did not receive chemotherapy after thyroidectomy but was still alive with PTL, and one patient just finished his second course of chemotherapy.

The diagnosis of PTL should be considered when dealing with rapidly growing goiters in elder female Hashimoto's thyroiditis patients whose B ultrasound indicates hypoechogenicity in thyroid nodules or parenchyma, especially with lymphadenopathy and tracheal compressions. Timely use of coreneedle biopsy on suspicious cases can avoid unnecessary surgical trauma, and chemotherapy is the main treatment.