Lymphoproliferative disorders of the thyroid gland: radiological appearances

Thyroid Cancer: Ultrasound Imaging and Fine-Needle Aspiration Biopsy

Ultrasound is critical in detection, diagnosis, and management of thyroid nodules. Ultrasound detection of regional nodal metastatic disease is based on abnormal nodal morphology rather than size and is critical to initial surgical and long-term management of thyroid cancer. Fine-needle aspiration biopsy is the gold standard for malignancy diagnosis in thyroid cancer. Thyroglobulin assay of nodal aspirates improves accuracy in diagnosis of metastases. Reporting lexicons assign risk levels to thyroid nodules with the goal of improving and standardizing patient management. Surveillance ultrasound in papillary microcarcinomas is being evaluated and compared with surgical management.

An unusual mature thyroid teratoma on CT and 99Tcm scintigraphy imaging in a child

We report the imaging findings of a mature thyroid teratoma in a 5-year-old girl. Nuclear imaging showed a decrease in (99)Tcm uptake in the right lobe of the thyroid gland. CT scan showed a slightly lobulated soft-tissue mass without calcification, fat or cystic components. Histological analysis showed that the tumor was composed of mature neural tissue, cartilaginous, and epithelial elements. This case study provides new insights into the CT appearance of mature thyroid teratomas.

[Non-Hodgkin's lymphoma in the thyroid: case report]

The authors describe the case of a 33 year-old white female, without any clinical or laboratorial evidence of thyroiditis or clinical hypothyroidism, who presented with a rapidly enlarging anterior neck mass. Diagnosis of a follicular non-Hodgkin's lymphoma was made through histopathological and immunohistochemical analysis.

Hodgkin and non-Hodgkin lymphoma of the head and neck: clinical, pathologic, and imaging evaluation

Lymphomas are subdivided into HL and NHL and are more specifically classified into subtypes of HL or NHL according to the WHO classification. HLs involve the lymph nodes predominantly and only approximately 5% arise in extranodal sites, whereas 30% of NHLs present in extranodal sites. Imaging studies, including CT and MR imaging, cannot distinguish [figure: see text] HL from NHL, and cannot differentiate their various subtypes, necessitating a pathologic diagnosis. Clinical parameters, however, can be helpful in differentiating the two broad categories of lymphomas, and subtypes of lymphomas have predilections for different sites within the head and neck. HL is most commonly located in the lymph nodes of the neck and mediastinum. Marginal-zone lymphoma has an affinity for the ocular adnexa, salivary glands, larynx, and the thyroid gland. Diffuse large B-cell lymphoma is commonly encountered in the paranasal sinuses, mandible, maxilla, and Waldeyer ring. Burkitt lymphoma occurs more frequently in children and young adults and frequently affects the maxilla and mandible, with a greater distribution of involvement at a lower frequency. On imaging studies, the lymph nodes of HL and NHL are homogeneous and variable in size, with an average diameter from 2 to 10 cm. They may enhance slightly to moderately, display necrosis before and after treatment, and display calcification post-treatment. NHL in extranodal sites in the head and neck (nasopharynx, Waldeyer ring, oral cavity, and larynx) manifests frequently as a submucosal mass accompanied [figure: see text] by polypoid, bulky masses with a smooth mucosal surface. Clinically aggressive lymphomas, such as Burkitt lymphoma, diffuse large B-cell lymphoma, and NK-/T-cell lymphomas are characterized by destruction of the maxilla, mandible, and bones around the paranasal sinuses, which is indistinguishable from bony destruction in other malignant tumors, such as SCC. Contrast CT is indicated for evaluation of cervical lymph nodes; the chest, including the mediastinum; the pelvic cavity; paranasal sinuses; and orbits. CT is also useful for detection of bone destruction involving the base of the skull, paranasal sinuses, and the mandible or maxilla. MR imaging is preferred for the assessment of extension of lymphomas to different fascial spaces (parapharyngeal, masticator, infratemporal fossa, tongue, and nasopharynx) and for intracranial extension. Lymphomas are isodense to muscle on CT and circumscribed with distinct margins that occasionally display extranodal extension with less-well-defined margins and areas of necrosis within the tumor matrix. Lymphomas appear low in signal intensity on T1-weighted images and low to high in signal intensity on T2-weighted images, with variable, but usually low, enhancement following introduction of Gadolinium-DTPA (Gd-DTPA) contrast material.

Primary thyroid lymphoma: CT findings

INTRODUCTION

To evaluate the computed tomographic (CT) findings of primary thyroid lymphoma.

METHODS AND MATERIAL

The clinicopathological data and CT images of nine patients with primary thyroid lymphoma were retrospectively reviewed. The CT appearances were classified into three types: type 1, a solitary nodule surrounded by normal thyroid tissue; type 2, multiple nodules in the thyroid, and type 3, a homogeneously enlarged both thyroid glands with a reduced attenuation with or without peripheral thin hyperattenuating thyroid tissue.

RESULTS

All patients had a rapidly enlarging thyroid mass and coexistent Hashimoto's thyroiditis. One patient showed type 1 pattern, three type 2, and five type 3. Six patients had homogeneous tumor isoattenuating to surrounding muscles. The tumors had a strong tendency to compress normal remnant thyroid and the surrounding structure without invasion.

CONCLUSION

Primary thyroid lymphoma should be included in the differential diagnosis when old female had a homogeneous thyroidal mass isoattenuating to muscles, which does not invade surrounding structures.

Rare tumors of the thyroid gland

Although the vast majority of thyroid cancers are well-differentiated and carry an excellent prognosis, several rare tumors occasionally involve the thyroid gland and require unique treatment paradigms. Anaplastic carcinoma of the thyroid is an extremely aggressive neoplasm that is generally best managed with surgery followed by a multimodality regimen of radiotherapy and chemotherapy. Squamous cell carcinoma of the thyroid often mimics the clinical course of anaplastic carcinoma and is best treated with aggressive surgery followed by postoperative radiotherapy. Treatment and prognosis of lymphoma of the thyroid varies depending upon the specific pathological subtype, with combination chemotherapy and radiation therapy used primarily. Sarcomas of the thyroid are primarily managed with surgery, although radiation and chemotherapy are indicated in some cases.

Scintigraphic findings of MALT lymphoma of the thyroid

Mucosa-associated lymphoid tissue (MALT) lymphoma has been established as a distinct entity among non-Hodgkin's lymphomas, and the most common primary site is the stomach. We describe scintigraphic findings in a patient with MALT lymphoma of the thyroid. A 71-year-old woman with Hashimoto's thyroiditis suffered from rapid cervical swelling, and ultrasonography and CT revealed a thyroid nodule. The nodule showed accumulation of 99mTc pertechnetate comparable to the surrounding thyroid tissue, mimicking a benign nodule. Both 67Ga and 201Tl imaging visualized the lesion as an increased uptake area. After radiotherapy, abnormally increased uptake disappeared on 67Ga images, which predicted a favorable outcome. MALT lymphoma of the thyroid may be visualized as a warm nodule on 99mTc pertechnetate scintigraphy.

[Thyroid scintigraphy and body scanning with 67 Ga in a case of primary thyroid lymphoma]

The case of a 60-year old woman first presented a rapidly growing left cervical mass is presented. The fine needle aspiration-puncture (FNAP) lead to a diagnosis of thyroiditis. Due to the persistence of the symptoms, the FNAP was repeated again but was not conclusive, so that a surgical biopsy was performed. The pathological diagnosis was diffuse large cell primary thyroid lymphoma (PTL). The PTL is a rare entity that accounts for less than 1% of all the Non-Hodgkin's lymphomas. The thyroid scintigraphy showed the existence of a cold nodule in the left thyroid lobule and the 67Ga scan revealed a large abnormal lesion in the mediastinum that extended to the right latero-cervical region. After two chemotherapy courses, the 67Ga scan was normal.

Ga-67 and Tl-201 scintigraphy in extramedullary plasmacytoma: a case report

Extramedullary plasmacytoma is a rare form of plasma cell tumor occurring in a wide variety of organs and tissues. Most tumors occur in the head and neck, involving the nasal cavity, paranasal sinuses, and upper airway. Tl-201 and Ga-67 scan findings in a patient with extramedullary plasmacytoma in the right side of the chest wall are presented. Only a few publications have described Tl-201 or Ga-67 uptake in extramedullary plasmacytoma. This is the first report of both Tl-201 and Ga-67 uptake in an extramedullary (or intramedullary) plasmacytoma.

The thyroid and parathyroid glands. CT and MR imaging and correlation with pathology and clinical findings

Thyroid imaging approach is based on the preliminary clinical evaluation. Lesions that are smaller than 2 cm should be assessed with US, which is capable of discriminating masses as small as 2 mm and distinguishing solid from cystic nodules. US-guided FNAB provides tissue for cytologic examination of thyroid nodules. CT and MR imaging are indicated for larger tumors (greater than 3 cm diameter) that extend outside the gland to adjoining structures, including the mediastinum, and retropharyngeal region. Metastatic lymph nodes in the neck and invasion of the aerodigestive tract are also in the realm of CT and MR imaging. Thyroid nodules are categorized on scintigraphy as hot or cold nodules. Hot nodules are rarely malignant, whereas cold nodules have an incidence of 10% to 20% of malignancy. Calcifications (amorphous, globular, nodular, and linear) occur in adenomas and carcinomas and have no differential diagnostic features except for psammomatous calcifications, which are a pathognomonic finding in papillary carcinomas and a small percentage of medullary carcinomas. Papillary carcinoma is the most common malignant tumor (80%) followed by follicular (20% to 25%); medullary (5%); undifferentiated; anaplastic carcinomas (< 5%); lymphoma (5%); and metastases. Lymph node metastases are common in papillary carcinoma, 50% at presentation, and less common in follicular carcinomas. The metastatic nodes in papillary carcinoma may enhance markedly (hypervascular); show increased signal intensity on T1-weighted images (increased thyroglobulin content or hemorrhage); and reveal punctate calcifications. Localized invasion of the larynx, trachea, and esophagus occurs predominantly in papillary and follicular carcinomas; the incidence is less than 5%. Ectopic thyroid tissue may be encountered in the tongue (foramen cecum); along the midline between posterior tongue and isthmus of thyroid gland; lateral neck; mediastinum; and oral cavity. Goiter and malignant tumors, notably papillary carcinoma, may develop in ectopic thyroid tissue. Carcinomas may also arise in thyroglossal duct cysts, which develop from duct remnants between the foramen cecum and thyroid isthmus. Infectious disease of the thyroid gland is not common and the CT and MR imaging findings are similar as described under neck infection. Other types of inflammatory disorders including Hashimoto's thyroiditis, granulomatous thyroiditis, and Riedel's struma display no specific imaging features. Imaging studies may, however, be indicated to confirm a suspected clinical diagnosis and assess compromise of the airway (Riedel's struma). HPT is a clinical diagnosis in which hypercalcemia is the most important finding. Parathyroid hyperplasia, adenoma, and carcinoma represent underlying lesions. To relieve the patient's symptoms surgical extirpation is indicated. The surgical success rate without imaging is 95%. The indications for imaging studies vary but it is generally agreed that reoperation after a previous failed surgical attempt and suspicion of an ectopic parathyroid adenoma should be investigated by imaging. These consist of US, nuclear medicine studies, CT and MR imaging. US and technetium sestamibi scanning have the highest accuracy rate for localizing an adenomatous gland at and near the thyroid gland. Ectopic adenomas, particularly if they are located in the mediastinum, are preferrably investigated with CT and MR imaging with gadolinium and fat suppression. Carcinomas and parathyroid cysts are optimally evaluated by CT and MR imaging. On MR imaging adenomas are low in signal intensity on T1-weighted images, high in signal intensity on T2-weighted images, and enhance post introduction of gadolinium.

Sonography of the thyroid and parathyroid glands

Sonography is the first line modality for assessment of thyroid and parathyroid pathologies. Sonographic and color Doppler patterns of diffuse and focal pathologies of the thyroid are presented in this article. The accuracy of sonography in the localization of enlarged parathyroid glands is also discussed. The limitations of sonography in specifying focal thyroid diseases and the problems in localizing ectopic parathyroid adenoma are addressed.

Primary non-Hodgkin's T-cell lymphoma of the thyroid gland complicating Hashimoto's thyroiditis: case report

This case report presents an extremely rare case of primary non-Hodgkin's T-cell lymphoma of the thyroid gland complicating Hashimoto's thyroiditis and discusses the clinical history, findings, treatment, and prognosis. Although the place of surgery in the treatment of thyroid lymphoma is controversial, in this case, surgery followed by three rounds of chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone, and radiation therapy to neck and mediastinum were a very effective treatment for the disease so that no relapse has been detected during 3-year follow-up.

Comparison of acquired cystic kidney disease between hemodialysis and continuous ambulatory peritoneal dialysis

OBJECTIVES

ACKD has been described mainly in patients treated with hemodialysis(HD), and there are only a few reports about the prevalence of ACKD in continuous ambulatory peritoneal dialysis (CAPD) patients. Therefore, we compared the prevalence of ACKD in patients receiving HD and CAPD, and evaluated the possible factors which may affect the development of ACKD.

METHODS

Forty nine HD and 49 CAPD patients who had received dialysis therapy for at least 12 months were enrolled in this cross-sectional study. Patients who had a past history of polycystic kidney disease and had acquired cystic kidney disease on predialysis sonographic exam were excluded. Detection of ACKD was made by ultrasonography and ACKD was defined as 3 or more cysts in each kidney.

RESULTS

The prevalence of ACKD was about 31% (30/98) and there was no significant difference between HD and CAPD patients(27% vs. 34%, p > 0.05). The prevalence of ACKD was not associated with age, sex, primary renal disease, the levels of hemoglobin, BUN, and serum creatinine. However, the duration of dialysis was significantly related to the development of ACKD (presence of ACKD, 74.4 +/- 42.4 months vs. absence of ACKD, 37.8 +/- 24.1 months, p < 0.05).

CONCLUSION

The prevalence of ACKD is not different according to the mode of dialysis, and the major determinant of acquired cyst formation is duration of dialysis.

Primary T-cell lymphoma of the thyroid

BACKGROUND

The routine use of immunocytochemical analysis has led to the recognition that many thyroid neoplasms previously diagnosed as anaplastic or small cell carcinomas are actually lymphomas of the thyroid. The great majority are B-cell lymphomas which can be associated with Hashimoto's thyroiditis. In spite of this, thyroid lymphomas are still not commonly recognized as a significant part of thyroid differential diagnosis.

METHODS

A rare case of a primary T-cell lymphoma of the thyroid gland is presented along with general clinical history and physical findings which should make the practitioner suspicious of a thyroid lymphoma. The usefulness of radiology scans and fine-needle aspiration are discussed.

RESULTS

Both prognosis and treatment options are very different for thyroid lymphomas and anaplastic carcinoma.

CONCLUSIONS

Cyclophosphamide/adriamycin/vincristine/prednisolone chemotherapy/radiotherapy regimens have proven to be very effective for most thyroid lymphomas.

Imaging the thyroid

Thyroid imaging has historically relied heavily on scintigraphy, although, not surprisingly in view of the superficial position of the gland, ultrasound has assumed an increasingly prominent role in recent years. The other cross-sectional imaging modalities can also be useful, and the emergence of new radiopharmaceuticals and the increasingly central role of fine needle aspiration cytology have further added to the range of diagnostic techniques available. This review attempts to summarize the current state of knowledge, and makes some suggestions for the most efficient use of imaging resources in the investigation of thyroid disease.

Primary plasmacytoma of the thyroid: a case report and comparative literature study between Western nations and Japan

A 52 year old man presented with primary thyroid plasmacytoma. The patient was initially followed up for thyroid dysfunction. The histological examination of the removed thyroid revealed a proliferation of mature and immature plasma cells indicative of plasmacytoma with Hashimoto's disease. After radiotherapy (40 Gy) to the neck following right hemi-thyroidectomy, the patient is currently alive and well 3 years after diagnosis without any evidence of tumor. The immunohistological examination of the removed thyroid showed monoclonality for immunoglobulin G-Kappa light chains. Sixty-six literature cases of primary thyroid plasmacytoma were reviewed and comparison of the clinical and histological characteristics between Japanese and Western cases noted. The incidence of the patients with antithyroid antibody was significantly lower (P < 0.01) in Western patients (42.9%) than in Japanese patients (87.5%). The higher incidence of thyroid dysfunction and Hashimoto's disease in Japan in comparison with Western nations was well reflected in the incidence of antithyroid antibody.

Imaging of lymphoma manifestations in the extracranial head and neck region

CT and MRI are the most efficient imaging techniques for diagnosing lymphomas while Gallium-67 scintigraphy is used to assess treatment results. In this review, the imaging aspects of lymphoma are addressed according to anatomical subregions, from the orbit to the trachea, Waldeyer's ring being the most common site, in the head and neck. Lymphomas of this region are not easily distinguished from the more common squamous cell carcinomas; however, multiple extranodal sites, the presence of many non-necrotic lymph nodes and a large nasopharyngeal mass without significant bone destruction should alert one to the possibility of lymphoma.

Plasma cell lesions of the thyroid: report of a case of solitary plasmacytoma and a review of the literature

We report a case of a solitary plasmacytoma arising from a thyroid with longstanding Hashimoto's disease, and diagnosed by fine-needle aspiration cytology. Serum protein electrophoresis revealed an M-spike in the gamma-globulin region due to monoclonal IgG-lambda immunoglobulin. The thyroid tumor was treated with near-total thyroidectomy and irradiation, and the patient was well 6 years after surgery without evidence of multiple myeloma. The serum M-spike disappeared after the tumor resection and radiation therapy. Plasma cell lesions of the thyroid reported in the world literature are extensively reviewed. Solitary plasmacytomas occur most commonly in patients with Hashimoto's disease, and must be distinguished from plasma cell granulomas and involvement of the thyroid in multiple myeloma. Plasmacytomas should be considered in the differential diagnosis of a rapidly enlarging thyroid mass in a patient with known Hashimoto's disease.