Primary T-cell lymphoma of the thyroid associated with Hashimoto's thyroiditis, histologically mimicking MALT-lymphoma

Comparison of the clinical characteristics of primary thyroid lymphoma and diffuse sclerosing variant of papillary thyroid carcinoma

OBJECTIVE

Both primary thyroid lymphoma (PTL) and diffuse sclerosing variant of papillary thyroid carcinoma (DSVPTC) are two rare malignant tumours with different therapies and prognoses. This study compared their clinical features.

METHODS

From a retrospective review of the pathologic database at our institute between January 2015 and August 2020, 52 PTL patients and 40 DSVPTC patients were included. Demographic, clinical, laboratory and ultrasound data were extracted from electronic medical records. Statistical analyses were performed using GraphPad Prism 5.0.

RESULTS

Both PTL and DSVPTC were more likely to occur in women (83.7 and 67.5%, respectively), but DSVPTC patients were younger (median age: 36 vs 64.5), had fewer compressive symptoms, and more frequently had neck lymph node metastasis than PTL patients. The prevalence of Hashimoto's thyroiditis (HT) and hypothyroidism was significantly higher in PTL patients than in DSVPTC patients (31% vs 17.5%). Hyperthyroidism could only be found in DSVPTC patients, which accounted for 7.5%. Heterogeneous echogenicity and irregular edges were frequently observed in both PTL and DSVPTC. However, compared with PTL, DSVPTC exhibited smaller lesion sizes, higher frequencies of diffuse sonographic patterns and calcification and lower frequencies of hypoechoic features and internal blood flow signal. The overall survival rate with PTL was 77.23%, which was lower than that with DSVPTC (90.91%), but this difference was not significant (P = 0.096).

CONCLUSION

Clinical characteristics such as age, compression symptoms, and sonographic features such as a large mass with heterogeneous echogenicity, hypoechoic, irregular edges, and calcification are helpful for impression diagnosis of PTL and DSVPTC before surgery.

Diagnostic challenges of indolent peripheral T cell lymphoma: A case report and literature review

INTRODUCTION

Peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) is a heterogeneous group of mature T cell lymphomas which do not correspond to any specific subtype of mature T-cell lymphoma in current classifications. Some researchers have suggested that PTCL with low Ki-67 labeling index should be classified as indolent PTCL PATIENT CONCERNS:: A 58-year old man diagnosed with alcoholic fatty liver 3 months prior complained of tenesmus and abdominal distension. Colonoscopy of the small and large intestines revealed multiple polyps, which were histologically diagnosed as lymphoid hyperplasia. One month later, he re-visited with a weight loss of 3 to 4 kg over 2 months. Radiologic examination revealed numerous small, homogenous, hypovascular lymph node enlargement in the para-aortic, mesenteric, and both inguinal areas, suggesting malignant lymphoma.

DIAGNOSIS

Laparoscopic biopsy of an omental lymph node was performed, which was histologically confirmed as PTCL-NOS.

INTERVENTIONS

The patient was administered 3 cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone, but his general condition did not improve. Therefore, treatment was changed to ifosfamide, carboplatin, and etoposide -dexamethasone (4 cycles) followed by allogeneic stem cell transplantation.

OUTCOME

Even after allogeneic stem cell transplantation, fluorodeoxyglucose uptake in his abdominal lymph nodes and small bowel in positron emission tomography- computed tomography persisted at a Deauville score of 4. The patient has been followed-up for 2 years without progression.

CONCLUSION

These indolent PTCLs histologically show diffuse infiltrated small lymphoid cells with low KI-67 labeling index and have a relatively good prognosis, although the epidemiology and pathogenesis are not fully elucidated. We report a case of indolent PTCL with cytogenetic abnormalities and poor response to chemotherapy, along with a brief review of the literature.

T-cell Lymphoma of Thyroid Gland with Lennert Type of Morphology: A Case Report and Review of the Literature

The rare entity of primary T-cell lymphoma of thyroid gland may pose great diagnostic and therapeutic challenges to the pathologist and clinician. There are very few case and short series reports of these tumors describing their varied clinicopathologic features in English literature. We report a case of mature T-cell lymphoma of thyroid in a 26 year old male, with unique pseudogranulomatous and lymphohistiocytic Lennert type of morphology, on a background of autoimmune thyroiditis. This man, diagnosed with Hashimoto's thyroiditis for the previous 2 years, underwent thyroidectomy for sudden onset of pressure symptoms. The diagnosis of T-cell lymphoma was made on the thyroid tissue based on histopathologic and immunophenotypic findings, in concert with the results of T-cell receptor gene rearrangement studies by polymerase chain reaction. Later, after about 3 months, similar findings were confirmed in an excision biopsy from a left cervical lymph node in the patient. The patient has been started on chemotherapy with gemcitabine, dexamethasone, and cisplatin along with involved field radiotherapy; however, he has shown a rapid upstaging of disease from stage IE to IIIE in a short period of 3 months with relatively well preserved clinical parameters until the latest follow up.

Primary thyroid T-lymphoblastic lymphoma: a case report and review of the literature

Most thyroid lymphomas are B-lineage, and T-cell lymphomas are rare. Here, we report a case of primary T-cell lymphoblastic lymphoma (T-LBL) of the thyroid gland. A 15-year-old boy presented with a painless thyroid mass. Ultrasonographic examination revealed a hypoechoic thyroid nodule measuring 4.6 cm × 1.9 cm × 3.4 cm. The thyroid function and antibodies were normal. Hemithyroidectomy was performed. Intraoperative frozen section was suggestive of malignant lymphoma. Histological examination showed diffuse round to oval medium sized cells with high nuclear/cytoplasmic ratio, finely dispersed chromatin, scanty cytoplasm, and numerous mitoses. Immunohistochemical studies revealed malignant cells were positive for terminal deoxynucleotidyltransferase, CD5, CD7, CD8, CD10, CD45RO, CD99, CD79a, CD3, CD1a and Ki-67 (>40%) and negative for CD34, CD20, BCL6, CD23, BCL2, Pax5 and EBV. A diagnosis of thyroid T-LBL was made. The patient was treated by intensive chemotherapy followed by allogeneic hematopoietic stem cell transplantation and has been in event-free survival for 65 months. The patient was unique because no cases of thyroid T-LBL have been previously reported, to our knowledge. Moreover, intensive chemotherapy followed by alloHSCT might be one of the adoptive options in therapy for this aggressive disease.