OBJETIVO:
El linfoma primario de tiroides es una enfermedad rara, que representa aproximadamente el 1 %-5% de todas las neoplasias malignas de la tiroides, y 1 % a 2,5 % de todos los linfomas. El linfoma de la zona marginal extranodal, del tejido linfoide asociado a mucosas (MALTOMA) es una neoplasia linfoide constituida por una poblaci贸n heterog茅nea de c茅lulas linfoides, as铆 como una cantidad variable de c茅lulas plasm谩ticas, sobre todo en los casos con diferenciaci贸n plasmocitoide. El tubo gastrointestinal es el sitio m谩s com煤n de desarrollo del MALTOMA, sin embargo, otros 贸rganos como la gl谩ndula tiroides pueden verse comprometidos por esta neoplasia. CASO CL脥NICO: El siguiente trabajo describe el caso de una paciente de 58 a帽os de edad, con n贸dulo tiroideo de 8 meses de evoluci贸n y crecimiento lento, asintom谩tica, eutiroidea, cl铆nicamente blando, m贸vil, ecogr谩ficamente n贸dulo solido de 5 cm en l贸bulo derecho de tiroides, PAAF Insatisfactoria para diagn贸stico, fue llevada a quir贸fano y se practic贸 tiroidectom铆a total + biopsia intraoperatoria cuyo resultado report贸 neoplasia folicular, con evoluci贸n posoperatoria satisfactoria, la biopsia definitiva report贸 MALTOMA de tiroides que no traspasa la c谩psula tiroidea, diagn贸stico corroborado por inmunohistoqu铆mica. Se practic贸 TAC para estadificar, sin evidenciar alteraciones por lo que se concluy贸 como MALTOMA de tiroides estadio IE, y se decidi贸 observaci贸n y seguimiento. CONCLUSI脫N: Se resaltan las caracter铆sticas morfol贸gicas de este tipo de linfoma primario de tiroides, su asociaci贸n con tiroiditis de Hashimoto, as铆 como su tratamiento y pron贸stico.

OBJECTIVE: The primary thyroid lymphoma is a rare disease, which represented approximately 1 % – 5 % of the thyroid malignancies, and 1 % to 2.5 % of all lymphomas. Extranodal marginal zone lymphoma of mucosa associated lymphoid tissue (MALT lymphoma), is an extra-nodal lymphoma composed of morphologically heterogeneous small B-cells including marginal zone cells centrocyte-like cells, monocytoid cells and scattered immunoblasts and centroblast-like cells; and also a variable number of plasma cells, especially in cases of plasma-cell differentiation. The gastrointestinal tract is the most common site of MALT lymphoma but other organs may be involved like thyroid gland. CLINICAL CASE:  It is a descriptive study of a patient of 58 years old, with thyroid nodule, 8 months of evolution and slow growth, asymptomatic, with euthyroid values, the physical examination soft and mobile thyroid nodule, in ultrasound solid, 5 cm in diameter, in right thyroid lobe, PAAF unsatisfactory for diagnosis, she was took to operating room and performed total thyroidectomy and intraoperative biopsy result was follicular neoplasm, with satisfactory postoperative evolution, the final biopsy report was (MALT) lymphoma of thyroid, did not cross the thyroid capsule, the diagnosis was confirmed by immunohistochemistry test, CT scan was performed to staging, so we concluded thyroid MALT lymphoma stage IE,  we decide observation and monitoring. CONCLUSION: The objective of this study is to describe morphologically this type of primary thyroid lymphoma, his association with Hashimoto’s thyroiditis and its treatment and prognosis.