The diagnosis of primary thyroid lymphoma by fine-needle aspiration, cell block, and immunohistochemistry technique

Fine Needle Aspiration of CD20-Negative Diffuse Large B Cell Lymphoma Presenting as an Anterior Neck Mass

Aggressive lymphoma of the neck presenting with life‐threatening airway compromise requires quick diagnosis, which can be rendered with fine needle aspiration cytology. In atypical cases, using multiple B cell markers can be helpful to avoid misdiagnosis.

Rare Thyroid Diseases Mimicking or Concealing Primitive Thyroid Neoplasms: A Call for a "Check and Double-Check" Clinical Mindset

Clinical endocrinologists encounter in their practice patients with thyroid diseases on a daily basis. Still, diagnosis of rare structural thyroid disorders can be quite challenging. In some instances, they do not only impersonate but can also conceal, other conditions such as thyroid carcinomas. We describe a series of patients with structural thyroid disorders including 1) anaplastic thyroid carcinoma initially presenting with features of thyroid abscess; 2) unicentric hyaline vascular Castleman's disease of the thyroid embedded in a stroma of papillary thyroid carcinoma; and 3) primary thyroid lymphoma with a rapid and fulminant evolution. The common challenge in the diagnosis of these cases lies in both their low incidence and their complex presentation. We use the presentation of these cases to raise the attention related to their identification. We highlight the need for precision diagnosis to enable a patient-tailored management approach and improve patient outcomes.

Primary Intrathyroidal Non-Hodgkin Lymphoma: A Case Report

Primary thyroid lymphoma (PTL) is a rare disease characterized by the appearance of a rapidly growing solid mass in the cervical region. A major risk factor is chronic autoimmune thyroiditis with lymphocytes infiltrating the thyroid gland. The lymphoproliferative disease is seen more frequently in the females. PTL usually develops in the sixth and seventh decades of life. We present a case of a 66-year-old woman with diffuse primary B-cell thyroid lymphoma with no prior evidence of underlying autoimmune thyroid pathology. The initial localization of the lymphoproliferative disease was in the thyroid gland, but the involvement of regional cervical lymph nodes was also found at the time of diagnosis. After histological verification with immunohistochemistry and staging by imaging, chemotherapy was initiated according to the R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin hydrochloride, Oncovin® (vincristine), prednisone) protocol. An excellent therapeutic response was achieved with lymphoma remission after six cycles under the mentioned protocol. Thyroid autoantibodies became positive 18 months after rituximab treatment, possibly reflecting the transient suppressive effects of the immunotherapy. The patient was subsequently kept followed up by a multidisciplinary team in the light of possible lymphoma recurrence and/or development of thyroid dysfunction. This case report demonstrates possible challenges for the diagnosis, treatment, and follow-up of this rare thyroid lesion. At the time of diagnosis, the clinical presentation of the disease, the ultrasound image, and the cytological result may be similar to other low-grade thyroid carcinomas or secondary metastatic involvement of the gland. The initial lack of underlying thyroid autoimmunity makes this distinction even more challenging. Furthermore, despite the rapid resolution, regular long-term monitoring for recurrence is required.

Small-Cell Malignancies of Thyroid: Challenge Solved?

"Small-cell malignancies of thyroid" is an unsolved dilemma. This term represents an umbrella terminology in thyroid, encompassing for a small group of tumors in which some of them are well-recognized tumors like medullary thyroid carcinoma, poorly differentiated thyroid carcinoma, and primary thyroid lymphomas and teratoma, whereas the remaining are less known as primary neuroendocrine carcinoma of thyroid, primary extraskeletal Ewing family tumors, and adamantinoma-like Ewing sarcoma. When the issue comes to evaluate a cytological sample predominantly composed of small-cell morphology, metastatic small-cell carcinomas to thyroid also should be excluded. In this review, our group focused on the main cytomorphological and clinical clues of each entity that help to set up a correct differential diagnosis. The literature discussions were also included for the entities that are not yet recognized by the mother publication WHO. A key point of the issue's simple algorithm based on FNAC with small-cell morphology of thyroid was suggested by the authors.

Fine-needle aspiration cytology of an intrathyroidal nodule diagnosed as squamous cell carcinoma: A case report

BACKGROUND

Both squamous cell carcinoma (SCC) and papillary thyroid carcinoma (PTC) are common malignant tumors in the neck. However, seldom has SCC of the thyroid been diagnosed. Further, cytological features of SCC and PTC have rarely been reported. The significance of fine-needle aspiration cytology (FNAC) in the diagnosis of neck masses has been established. Herein, we present an exceedingly rare case of an intrathyroidal SCC diagnosed using FNAC, along with its cytological features.

CASE SUMMARY

A 66-year-old man presented with a left-sided neck mass. Ultrasound examination showed an ill-defined nodule. The appearance was hypoechoic with a few hyperechoic spots. FNAC of the left thyroid nodule was performed. A cellular smear was obtained, and it showed a large number of neoplastic cells with rich cytoplasm and poor cell adhesion. Tumor cell nuclei showed coarse nuclear chromatin and a few enlarged prominent nucleoli. An increased nuclear/cytoplasm ratio was observed. Thus, malignancy was diagnosed without a confirmed tumor type. Percutaneous tumor biopsy was performed to make a definite diagnosis. The tumor cells showed typical squamous cell characteristics.

CONCLUSION

Head and neck SCC and PTC have different cytologies. Measures are needed to ensure accurate diagnosis using FNAC.