Malignant lymphomas of the thyroid: a clinical pathologic study of 35 patients including ultrastructural observations

The sonographic appearance of benign and malignant thyroid diseases and their histopathology correlate: demystifying the thyroid nodule

The thyroid gland is one of the largest endocrine glands in the human body. It functions as a regulator of metabolism. Diseases involving the thyroid range from benign to malignant and can be associated with major morbidity and mortality. Ultrasound (US) imaging of the thyroid gland is prompted because of a palpable mass on clinical examination; abnormality of thyroid function tests; incidental finding on other imaging modalities, that is, nuclear scintigraphy or computed tomography scan; screening for patients with risk factors for malignancy, such as multiple endocrine neoplasia type II; or prior neck radiation treatment.Ultrasound is an excellent, noninvasive, and cost-effective diagnostic tool in the detection and characterization of thyroid disease. Most thyroid diseases have pathognomonic features on US, which are of diagnostic importance and lead to appropriate clinical management. Ultrasound plays an important role in differentiating benign from malignant thyroid disease, thereby triaging patients for US-guided fine-needle aspiration. Ultimately, thyroid US, in conjunction with thyroid function tests, can aid in characterizing various thyroid diseases.The main objective of this pictorial essay is to illustrate the sonographic appearance of various benign and malignant diseases of the thyroid with their histopathology correlations. Management of thyroid nodules using US-guided fine-needle aspiration is also briefly discussed.

Hematological Evaluation of Primary Extra Nodal Versus Nodal NHL: A Study from North India

Primary extra nodal lymphomas (EN-NHL) are different from primary nodal non-Hodgkin's lymphoma (N-NHL) and are comparatively less common. Hemogram findings and bone marrow involvement is less studied and very few reports are available in the literature. The present study is a retrospective analysis of bone marrow samples evaluated for staging of non-Hodgkin's lymphoma. The age, sex distribution, clinical features, and site of presentation, hemogram findings, pattern of bone marrow involvement and grade of reticulin fibrosis was noted. These findings were compared with the type of non-Hodgkin's lymphoma and prognostic information was determined. A total of 647 cases of NHL, which underwent bone marrow examination for staging, over a seven year period, were retrieved and analyzed for all hematological parameters. Prevalence of EN-NHL was 23.5% (152/647), while nodal NHL comprised 76.5% (495/647) of all NHL cases. 90.1% (137/152) cases of EN-NHL were adult patients, out of which 15.3% (21/137) cases showed bone marrow infiltration as compared to 89% (441/495) adult primary nodal NHL cases, of which 39% (175/441) showed bone marrow infiltration. 9.9% (15/152) cases of EN-NHL were pediatric patients, out of which 40% (6/15) showed bone marrow infiltration, while 10.9% (54/495) of nodal NHL cases were pediatric, of which 20.3% (11/54) showed bone marrow infiltration. Hemogram findings were not found useful in predicting bone marrow infiltration in both nodal as well as EN-NHL. 100% (6/6) of pediatric patients had high grade lymphoma as compared to 48% (9/21) of adult patients, showing bone marrow infiltration in EN-NHL group. Reticulin fibrosis also did not reveal relation with grading of NHL. Prognostically EN-NHL of stomach and central nervous system were found to be better than EN-NHL of other sites, as none of these cases showed bone marrow infiltration. EN-NHL can involve various sites and the prognosis depends upon the sites of disease as well as the type of NHL. Moreover, pediatric EN-NHL cases are likely to have poorer prognosis, due to increased risk of bone marrow involvement as compared to their counterparts having primary nodal NHL. Bone marrow infiltration at times cannot be assessed reliably from hemogram findings only and a bone marrow biopsy for staging is mandatory.

Primary thyroid lymphoma: role of ultrasound-guided needle biopsy

OBJECTIVE

The purpose of this study was to describe the sonographic findings of primary thyroid lymphoma and evaluate the role of ultrasound-guided biopsy in diagnosing thyroid lymphoma.

METHODS

This study included 6 patients (age range, 56-72 years; mean, 62.5 years). We searched the database of our institution and retrospectively collected data on the thyroid lymphomas that were confirmed pathologically. All of the sonograms and medical records were reviewed retrospectively.

RESULTS

All 6 patients had an enlarged neck mass and underwent ultrasound-guided fine-needle aspiration biopsy. The most notable sonographic feature of primary thyroid lymphoma was a marked hypoechoic mass compared with the residual thyroid tissue. Among the 6 patients with a diagnosis of thyroid lymphoma, 3 (50%) had a diagnosis of lymphoma by ultrasound-guided fine-needle aspiration biopsy. Final pathologic results were obtained by ultrasound-guided core needle biopsy (3/6 patients [50%]) or thyroidectomy (3/6 [50%]). Most patients with thyroid lymphoma (5/6 [83.3%]) were found to have diffuse large B-cell lymphoma and were treated with chemotherapy with or without radiotherapy. In 1 patient with follicular lymphoma, diagnosis and treatment were accomplished by total thyroidectomy.

CONCLUSIONS

Our results show that ultrasound-guided core needle biopsy can be a safe and accurate method for diagnosing thyroid lymphoma and may be a suitable replacement for diagnostic thyroid surgery.

Outcomes of primary thyroid non-Hodgkin’s Lymphoma

Primary non-Hodgkin's lymphoma (NHL) of the thyroid gland is a rare disease with an incidence of 0.5 per 100,000 population. Stages IE and IIE thyroid NHL have been traditionally treated by surgical resection; however, modern treatment consists of chemotherapy and local radiotherapy, and surgery is often reserved for tissue diagnosis and relief of airway compression. We retrospectively reviewed the management and outcomes of nine consecutive patients with thyroid NHL, eight females and one male (median age 63 yr, range 34-71 yr) treated between 1994 and 1999. Five patients had disease stage IE and 4 stage IIE. Median follow-up was 72 mo. Pathohistology and immunohistochemistry identified two patients with mucosa-associated lymphoid tissue (MALT), three follicular center cell lymphoma (FCC), two patients large B-cell lymphoma (BLCL), one a marginal zone lymphoma (MZL), and one patient a peripheral T-cell lymphoma (PTCL). Total thyroidectomy was performed in three patients and subtotal thyroidectomy in four. One (MALT) patient underwent surgery alone; three patients surgery, radiotherapy, and chemotherapy (two FCC, one PTCL); three patients surgery and chemotherapy (one MALT, one FCC, one LBCL); and two chemotherapy alone (one LBCL, one MZL). Median survival was 79 mo (range 13-124 mo). The PTCL patient, a 34-yr-old man, died from disseminated disease at 13 mo despite secondary chemotherapy, and one LBCL patient with extensively invasive local disease died from stroke 17 mo after diagnosis. The remaining seven patients remain in remission with no local or systemic relapse at a mean of 86 mo. With appropriate therapy primary thyroid NHL has a favorable course; however, prognosis depends on the histology, local spread, and the stage of the disease at presentation, as well as the patient's performance status. Surgery in combination with chemotherapy and/or radiotherapy is still warranted for intermediate and high-grade thyroid NHLs, with over 77% of patients achieving long-term remission. Peripheral T-cell lymphoma carries a poor prognosis.

AIDS-Related Lymphoma

OBJECTIVE

To review the epidemiology, pathology, clinical features, prognostic factors, and treatment approaches of patients with AIDS-related lymphoma.

DATA SOURCES

Research studies and review articles.

CONCLUSION

Aggressive B-cell lymphoma has become one of the more common of the initial AIDS-defining illnesses in the United States. Median survival of affected patients has improved considerably with the use of highly active anti-retroviral therapy directed against human immunodeficiency virus, along with multi-agent chemotherapy, and outcome of such patients now approaches that of human immunodeficiency virus-negative patients with aggressive lymphoma.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses must be knowledgeable of AIDS-related lymphoma to provide supportive care to this patient population.

Ultrasound of thyroid cancer

The management of thyroid nodules is multi-disciplinary and involves head and neck surgeons, pathologists and radiologists. Ultrasound is easy to perform, widely available, does not involve ionizing radiation and is readily combined with fine needle aspiration cytology (FNAC). It is therefore an ideal investigation of choice for evaluating thyroid nodules. It evaluates specific features that help in identifying the nature of the nodule and FNAC helps in diagnostic accuracy. In addition, following treatment for thyroid cancer ultrasound provides a safe tool for disease surveillance. This paper discusses the role of ultrasound in the management of patients with thyroid cancer.

Management of non-Hodgkin's lymphoma of the thyroid: the Royal Marsden Hospital experience

A retrospective review was conducted of patients treated for thyroid non-Hodgkin's lymphoma (TNHL) at the Royal Marsden Hospital between 1936 and 1996 to determine the effect of radiotherapy (RT) on outcome. 91 patients were identified from the Thyroid Unit Database. There were 77 females and 14 males with a median age of 65 years (range 22-87 years). RT was delivered according to two separate policies: (1) involved field radiotherapy (IFRT) to the thyroid bed and cervical lymph nodes; (2) extended field radiotherapy (EFRT) covering the thyroid bed, cervical and mediastinal lymph nodes. 89 patients received RT as part of definitive treatment following surgery, to a dose of approximately 40 Gy. 25 patients received IFRT and 64 patients EFRT. 27 patients received cytotoxic chemotherapy. 18 patients (72%) treated with IFRT died of TNHL with a median relapse free survival (RFS) of 10 months and a median overall survival (OS) of 21 months. In contrast, only 29 patients (46%) treated with EFRT died of TNHL with a median RFS of 76 months (p = 0.01 for RFS with respect to IFRT and p = 0.04 for OS). Significantly more patients treated with IFRT relapsed locally (52% vs 27%). There was no difference in the rates of systemic relapse (20% vs 22%). EFRT alone for Stage I, but not for Stage II disease, yielded acceptable rates of local control and disease free survival with doses of at least 40 Gy. These historical data strongly support the addition of combination chemotherapy to the treatment regimen in all patients with Stage II disease. Indeed, in recent years this has become the standard of care for all cases of thyroid lymphoma unless the histology is of marginal zone type (mucosa associated lymphoma tissue (MALT) lymphoma).

Diagnosis of thyroid lymphoma and follow-up evaluation using Ga-67 scintigraphy

A strong association between malignant lymphoma and Hashimoto's thyroiditis has frequently been reported. However, it is difficult to detect the lymphomatous transformation of Hashimoto's thyroiditis in the early stage. The purpose of the present study was to examine the usefulness of 67Ga scintigraphy in the diagnosis and evaluation of the therapeutic effects during follow-up, in patients with a suspected diagnosis of primary thyroid lymphoma. Twenty-five patients who were suspected of having primary thyroid lymphoma and had undergone 67Ga scintigraphy were studied. 67Ga planar scintigraphy was performed 72 hours after injection of 67Ga-citrate. The degree and pattern of 67Ga accumulation were graded visually. Histopathology on biopsy examination revealed thyroid lymphoma in 17 and Hashimoto's thyroiditis in 8 patients. Abnormal accumulation of 67Ga in the thyroid was seen in all of the 17 thyroid lymphoma cases with additional mediastinal and abdominal involvement in one. Fifteen of 17 thyroid lymphoma patients also underwent 67Ga scintigraphy 2-4 weeks after chemotherapy and/or radiotherapy. All 15 patients showed diminishing 67Ga accumulation and a good clinical course. In one patient with local recurrence, abnormal accumulation could be depicted by follow-up scintigraphy. However, diffuse or enlarged accumulation in the thyroid was seen in all of the 8 Hashimoto's thyroiditis cases. The degree of abnormal accumulation in the thyroid in clinically active phase thyroiditis was more intense than that in the chronic phase thyroiditis. 67Ga scintigraphy was helpful to confirm the diagnosis of thyroid lymphoma and to evaluate the therapeutic effects during follow-up. However, 67Ga scintigraphy may not always distinguish thyroid lymphoma from Hashimoto's thyroiditis, especially the active phase of the disease.

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.

Insular Carcinoma of the Thyroid

Thyroid surgeons are becoming increasingly more aware of a histologically distinct subset of thyroid carcinoma whose classification falls between well-differentiated and anaplastic carcinomas with respect to both cell differentiation and clinical behavior. This subtype of tumors has been categorized as poorly differentiated or insular carcinoma, based on its characteristic cell groupings. Although the differentiation of insular carcinoma from other thyroid carcinomas has important prognostic and therapeutic significance, relatively little about insular carcinoma has been published in the otolaryngology literature. In this article, we describe a new case of insular carcinoma and we discuss the findings of our review of the literature. We conclude that insular thyroid carcinoma warrants aggressive management with total thyroidectomy followed by radioactive iodine ablation of any remaining thyroid tissue.

Fine needle aspiration cytology of primary lymphoma of the thyroid: a report of 17 cases

Between 1980 and 1998, 4272 thyroid surgical specimens with a preoperative fine needle aspirate were sent to our Anatomical Pathology Department. Among these cases there were 17 primary thyroid lymphomas, which constituted 0.3% of all the thyroid lesions and 2.3% of the thyroid malignancies. Seven cases were diffuse large B-cell (DLBC) lymphomas and 10 were MALT lymphomas. Of the DLBC lymphomas six were correctly diagnosed by fine needle aspiration cytology (FNAC) and one was diagnosed as positive for malignancy, and among MALT lymphomas four were diagnosed as lymphoma, four as suspicious for lymphoma, and three as Hashimoto's thyroiditis (HT). Our data indicate that the diagnosis of primary thyroid lymphoma of high grade is easy, and immunocytochemistry (ICC) can confirm suspicious cases. The diagnosis of MALT lymphoma is more difficult; ICC can confirm suspicious cases, and false-negative results seem to be caused by sampling error, because HT usually coexists with MALT lymphoma.

Primary thyroid lymphoma: a retrospective analysis of prognostic factors and treatment outcome for localized intermediate and high grade lymphoma

Non-Hodgkin's lymphoma presenting in the thyroid gland is uncommon. A review of the King Faisal Specialist Hospital and Research Centre (KFSH & RC) experience was performed to assess treatment outcome and prognostic factors in this rare extranodal presentation of localized lymphoma. Sixty patients treated at KFSH & RC between 1975 and 1995 were identified, and their records were reviewed retrospectively. Eight patients who had stage III or IV disease, low grade, or did not complete their prescribed treatment were excluded from the study. There were 38 female and 14 male patients with a median age of 59.5 years at the time of diagnosis (range: 10-87 years). Thirty-five of the 52 patients underwent diagnostic partial or total thyroidectomy at other institutions based on a preoperative assumption of thyroid carcinoma. All 52 patients had non-Hodgkin's lymphoma of intermediate (94%) or high (6%) grade. Detailed staging was carried out in all patients; 16 patients (31%) had disease confined to the thyroid gland (stage IE), whereas 36 (69%) had associated disease in cervical lymph nodes and/or the mediastinum (stage IIE) disease. All patients were treated with curative intent. A total of 18 patients (35%) were treated with a single-modality treatment--radiotherapy alone in 2, chemotherapy alone in 13, and surgery alone in the remaining 3 patients. The majority of patients (34/52; 65%) were treated with a combined-modality approach. The overall relapse-free survival (RFS) and overall survival (OS) at 5 years were 72% and 88%, respectively. There were no significant differences in outcome between those treated with single-modality and those with combined-modality therapy. A univariate analysis showed that the presence of mediastinal lymph node involvement was the most important prognostic factor affecting both RFS and OS. Patients with Hashimoto thyroiditis and without "B" symptoms were found to have a significantly higher RFS without influence on the OS. However, patients who had a good performance status (PS) of 0, 1, and 2 were found to have a significantly higher overall survival in comparison to those with poor performance status. Age, sex, stage, histology, lactic acid dehydrogenase level, tumor bulk, and the treatment modality were not found to correlate with RFS or OS. Mediastinal involvement and PS were found to be the most important independent prognostic factors influencing RFS and OS.

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.

Large B-cell lymphoma of thyroid. Two cases with a marginal zone distribution of the neoplastic cells

We report 2 cases of B-cell lymphoma of the thyroid in which although a marginal zone distribution of the neoplastic cells was present, the cytologic features of the cells indicated large cell lymphoma. One of the cases showed an accumulation of crystalline inclusions within the cytoplasm of the neoplastic cells. Many of these inclusion-bearing cells showed plasmacytoid features. By immunohistochemical studies performed on formalin-fixed paraffin-embedded tissue, both of the cases showed a B-cell phenotype as indicated by CD20 expression, and 1 showed kappa light chain restriction. In both cases, Ki-67 staining corroborated the impression of an aggressive neoplasm with staining of 50% and 90% of the tumor cells. Both patients received cyclophosphamide, doxorubicin, vincristine, and prednisone with radiation therapy, and both are without evidence of disease after 17 and 18 months of follow-up. It is important to recognize this pattern of large B-cell lymphoma of the thyroid gland. While the indolent course typical of most low-grade extranodal marginal zone lymphomas is not likely in these cases, the outcome may be favorable if patients are treated aggressively with therapy for large cell lymphoma.

A reassessment of primary thyroid lymphoma: high-grade MALT-type lymphoma as a distinct subtype of diffuse large B-cell lymphoma

AIMS

Primary lymphoma of the thyroid gland (PTL) is a relatively rare disease. During an 18-year period, 53 cases of primary non-Hodgkin's lymphoma involving this extranodal site were seen at our institutions. The aims of this study were to evaluate the spectrum of PTLs using current lymphoma classification concepts and immunocytochemical markers, determine whether features of MALT-type lymphoma were evident in PTL, and if there was any clinical significance of such a finding.

METHODS AND RESULTS

The cases were retrospectively studied clinically, histologically and immunohistochemically. The tumours were classified according to the Revised European-American Lymphoma Classification of lymphoid malignancies (REAL classification). Thirty-eight patients were females, 15 were males and mean age at diagnosis was 66.3 years (range 38-90). Three cases were low-grade marginal zone lymphomas (low-grade MALT-type lymphomas). There were 45 diffuse large B-cell lymphomas (DLBCL) of which there were 27 DLBCL-NOS and 18 high-grade MALT-type lymphomas. Within the diffuse large B-cell lymphoma (DLBCL) category, cases were subdivided into those without (DLBCL-NOS) and those with features of 'high-grade' MALT-type lymphoma based on presence of a low-grade component or large cell lymphoepithelial lesions (HG MALT-type lymphoma). In addition there were three follicle centre lymphomas, one anaplastic large cell lymphoma and one peripheral T-cell lymphoma. Twenty cases were stage IE, 18 stage IIE, and four stage IV. All patients with low-grade MALT-type lymphoma are alive without disease. The 5-year survivals for DLBCL-NOS and HG MALT-type lymphoma were 75% and 25%, respectively. Univariate analysis (log rank) among the DLBCLs showed stage (P < 0.001) and subtype (P = 0.005) were associated with survival. Stage was associated with type of DLBCL, 65% of DLBCL-NOS being stage IE compared to 20% of HG MALT-type lymphomas.

CONCLUSIONS

We conclude that primary thyroid lymphomas occur most commonly in elderly women and are frequently present in clinical stage IE and IIE. Low-grade MALT-type lymphomas are relatively uncommon but appear to have a favourable prognosis. DLBCL is the most common lymphoma and features of MALT can be seen in over one-third of cases. As a group, HG MALT-type lymphomas had a worse outcome than DLBCL-NOS, primarily due to higher clinical stage at diagnosis. These two subtypes of DLBCL appear to be distinct clinical and histological entities.

Primary thyroid lymphoma: diagnosis of immunoglobulin heavy chain gene rearrangement with polymerase chain reaction in ultrasound-guided fine-needle aspiration

We present a case of primary thyroid lymphoma coexisting with Hashimoto's thyroiditis in a 75-year-old woman in whom B-cell lymphoma was substantiated based on the findings of immunophenotyping and polymerase chain reaction (PCR) gene rearrangement in specimens that had been obtained by ultrasound (US)-guided fine-needle aspiration biopsy (FNAB). The immunophenotyping technique showed A light chain restriction, and PCR-based assays showed a discrete narrow band, which was diagnostic for clonal B-cell proliferation. Analyses of PCR gene rearrangement in US-guided FNAB may be a useful ancillary technique to pathological findings for diagnosis of primary thyroid lymphoma, especially for differentiation between low-grade B-cell lymphomas and Hashimoto's thyroiditis.

Malignant lymphoma of the thyroid gland: a clinicopathologic study of 108 cases

We report a retrospective clinicopathologic study of 108 primary thyroid gland lymphomas (PTLs), classified using the REAL and proposed WHO classification schemes. The patients included 79 women and 29 men, with an average age of 64.3 years. All patients presented with a thyroid mass. The PTLs were classified as marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) or MZBL (n = 30), diffuse large B-cell lymphoma (DLBCL) with MZBL (n = 36), DLBCL without MZBL (n = 41), and follicle center lymphoma (FCL; n = 1). Excluding the FCL, features of lymphomas of MALT-type were identified in all groups, despite a follicular architecture in 23% of cases. Lymphocytic thyroiditis (LT) was identified in 94%. Ninety-one percent of patients presented with stage IE or IIE disease, whereas 69% had perithyroidal soft tissue infiltration. All patients were treated with surgical excision followed by adjuvant therapy (76%): chemotherapy (15%), radiation (19%), or a combination of radiation and chemotherapy (42%). Disease-specific survival was 82% at last follow up (mean, 82.8 mos) and 79% at 5 years. Statistically, stages greater than IE, presence of DLBCL, rapid clinical growth, abundant apoptosis, presence of vascular invasion, high mitotic rate, and infiltration of the perithyroidal soft tissue were significantly associated with death with disease. No patients with MZBL or stage IE disease died with disease. In summary, PTLs typically occur in middle- to older-aged individuals as a thyroid mass, with a predilection for females. Despite their histologic heterogeneity and frequent simulation of other lymphoma subtypes, virtually all PTLs are lymphomas of MALT-type arising in the setting of LT. Mixed DLBCL and MZBL are common. Overall, PTLs have a favorable outcome with appropriate therapy, but prognosis depends on both clinical stage and histology. MZBL and stage IE tumors have an excellent prognosis, whereas tumors with a large cell component or DLBCL or stage greater than IE have the greatest potential for a poor outcome.

Secondary malignant lymphoma which simulated primary thyroid cancer

A patient with secondary thyroid lymphoma who complained of a neck mass was presented. Multiple nodules were detected in both lobes of the thyroid gland, which appeared as homogeneous hypoechoic masses on ultrasonogarphy (US), low-density masses on computed tomography (CT), and areas of increased uptake on gallium-67 scintigraphy. The residual thyroid gland was normal. Surgery established a diagnosis of secondary thyroid lymphoma with no coexistent Hashimoto's thyroiditis but with cervical node involvement by lymphoma. Radiologic evidence of normal residual thyroid gland in a patient with thyroid lymphoma may be a sign of secondary thyroid lymphoma.

Lymphoid lesions of the thyroid: review in light of the revised European-American lymphoma classification and upcoming World Health Organization classification

Thyroid lymphomas are rare diseases and almost always rise in the background of chronic lymphocytic thyroiditis (Hashimoto's thyroiditis). Large cell lymphoma is an aggressive disease and usually is not a significant diagnostic challenge from the pathological point of view. Small cell lymphoma, however, can sometimes be difficult to distinguish from chronic lymphocytic thyroiditis. In the past, most thyroid lymphomas were considered to be of follicle center cell origin. Today, after the introduction of the mucosa-associated lymphoid tissue (MALT) and the extranodal lymphoid tissue (ELT) concepts, most of the lymphomas in the extranodal sites are thought to originate from the marginal zone of the lymphoid follicles. The distinction between the different types of lymphomas has significant impact on the patient's prognosis, treatment, and follow-up. It is imperative that clinicians (endocrinologists and surgeons) and pathologists are aware of these types of lymphomas in order for the most appropriate diagnostic procedures to be selected, specific staging principles to be applied, and appropriate disease-specific treatment to be implemented. It is also important that terms such as "lesion of uncertain malignant potential" as defined by ancillary studies be understood.

Non-Hodgkin's lymphoma followed by plasmacytoma, both arising in A thyroid gland with Hashimoto's disease

We describe here a rare case of malignant lymphoma followed by plasmacytoma in Hashimoto's thyroiditis. The patient developed malignant lymphoma (small, non-cleaved cell, and non Burkitt's type by Working Formulation classification), and remained in remission for 2 years after receiving combination chemotherapy, and then developed plasmacytoma in the same lesion. Rearrangement bands for IgH from both specimens showed different bands, indicating that both were of monoclonal type but of a different clonal origin. Considering the clinical course in this case, thyroidectomy may be indicated for lymphoproliferative diseases in Hashimoto's thyroiditis treated with chemotherapy.

Primary thyroid lymphoma associated with metastatic thyroid tumor: discrimination with US

We surgically treated a 75-year-old man who suffered from metastatic adenocarcinoma from the colon associated with primary thyroid lymphoma measuring 1 cm maximum in diameter. Radiologic findings were correlated with histopathology of excised specimens. Ultrasonography could discriminate between these two tumors based on the margin characteristics and the lesion echogenicity: the metastatic tumor was shown as an ill-defined hypo to iso echoic mass, while the malignant lymphoma was detected as a well-defined markedly hypoechoic mass. In addition, we could confirm that early-stage primary thyroid lymphoma even as small as 1 cm shows the same radiologic appearance as that of a bulky lymphoma.

Etiology and pathogenesis of AIDS-related non--Hodgkin's lymphoma

The incidence of NHL is greatly increased in HIV-infected individuals. The vast majority are clinically aggressive B cell-derived neoplasms exhibiting BL, IBL, or LCL histology. Approximately 80% arise systemically (nodal and/or extranodal), and the remaining 20% arise as primary CNS lymphomas. A small proportion are body cavity-based lymphomas associated with KSHV infection. Possible factors contributing to lymphoma development include HIV-induced immunosuppression, chronic antigenic stimulation, and cytokine overproduction. These alterations are associated with the development of oligoclonal B-cell expansions. The appearance of NHL is characterized by the presence of a monoclonal B-cell population displaying a variety of genetic lesions, including EBV infection, c-myc gene rearrangement, bcl-6 gene rearrangement, ras gene mutations, and p53 mutations/deletions. The number and type of genetic lesions varies according to the anatomic site and histopathology. In the case of BL, virtually 100% exhibit c-myc gene rearrangements, two thirds display p53 gene mutations, one third contain EBV, and none exhibit bcl-6 gene rearrangements. In contrast, in the case of IBL, virtually 100% contain EBV, 25% display c-myc gene rearrangements, 20% display bcl-6 gene rearrangements, and very few exhibit p53 gene mutations. These findings suggest that more than one pathogenetic mechanism is operational in the development and progression of AIDS-related NHLs. Further work will be necessary to develop a complete understanding of the etiology and pathogenesis of NHL in the setting of HIV infection. AIDS-related NHL remains an important biologic model for investigating the development and progression of high-grade NHLs as well as NHLs that develop in immune-deficient hosts.

Surgical considerations and approach to thyroid cancer

Patients with thyroid cancer can be safely treated by an experienced endocrine surgeon. More extensive initial surgery such as total or near-total thyroidectomy seems to decrease tumor recurrence and prolong life. When such operations can be done with minimal complications, we believe it is the treatment of choice because even low-risk patients have a 4% or 5% risk of eventually dying of thyroid cancer. If this risk of death from thyroid cancer can be decreased to 1% or 2% and the rate of serious complications is 1% or 2%, the authors believe total thyroidectomy is indicated. Most patients can be discharged within 1 day of total thyroidectomy.

Pseudolymphoma of the thyroid gland. A case report

An unusual case of pseudolymphoma of the thyroid gland is presented. A well-demarcated whitish mass measuring 1.0 cm in diameter was found in the upper center of the right lobe of the thyroid gland. Microscopically, the lesion was composed of hyperplastic lymphoid tissues with many follicular centers and mixed infiltration of plasma cells and macrophages. The immunostain revealed a similar distribution of T-and B-lymphocytes to reactive lymph node and a polyclonal nature of the plasma cell infiltrates. No lymphoepithelial lesion was associated. The adjacent thyroid tissues showed chronic lymphocytic thyroiditis. This finding suggests that the lesion is a pseudolymphoma of the thyroid gland. This condition is rare, but it should be considered during the differential diagnosis of lymphoproliferative lesions occurring in the thyroid gland, especially with low-grade malignant lymphoma of the thyroid gland.

Systemic immunosuppressive therapy and the occurrence of malignancy in patients with ocular inflammatory disease

PURPOSE

To compare the occurrence of malignancy in patients with severe ocular inflammatory disease treated with systemic corticosteroids alone or with systemic immunosuppressive drugs with or without systemic corticosteroids.

METHODS

The clinical records of 543 patients with ocular inflammatory disease treated with systemic corticosteroids and/or immunosuppressive chemotherapy were reviewed in a retrospective cohort study. Characteristics of patients treated with corticosteroids alone were compared with characteristics of patients treated with immunosuppressive agents with or without preceding corticosteroid treatment. The rates of malignancy after initiation of drug therapy were compared using an exact test for incidence rate data.

RESULTS

Compared with patients treated with corticosteroids alone, patients treated with immunosuppressants with or without corticosteroid treatment were older and had more severe systemic disease. During a total of 1261 person-years of follow-up, a malignancy developed in five patients. The rate of malignancy in the immunosuppressant group (4 malignancies during 968 person-years of follow-up) was not significantly different from the rate in the corticosteroids alone group (1 malignancy during 293 person-years of follow-up) (P > 0.90, exact test for incidence rate data).

CONCLUSION

These findings do not support the hypothesis of an increased risk of malignancy in patients with severe ocular inflammatory disease who are treated with systemic immunosuppressive agents compared with patients treated with systemic corticosteroids.

Contribution of Epstein-Barr virus to development of malignant lymphoma of the thyroid

Epstein-Barr virus (EBV)-related mRNA, their products and apoptosis were investigated in 32 cases of malignant lymphoma of the thyroid (MLT) and 30 cases of Hashimoto's thyroiditis (HT) by in situ hybridization, immunohistochemistry and nick end labeling method on routinely processed tissue sections. In MLT, EBV-encoded small RNA (EBER) were detected in three cases, consisting of a follicular, predominantly large cell type (FL), a diffuse, large cell type (DL) and a large cell, immunoblastic type (IBL). In EBER-positive cases, IBL that was positive for T cell marker, exhibited neither BamHl H Left Frame 1 (BHLF1) transcript, EBV-encoded latent membrane protein (LMP) nor BamHl Z Left Frame 1 (BZLF1) gene product (ZEBRA), whereas both BHLF1 and ZEBRA were found in a small portion of the tumor cells in the FL and DL that expressed B cell marker and LMP. Apoptotic cells were observed in only a few lymphocytes in HT, and in a few non-neoplastic lymphocytes and various numbers of lymphoma cells in MLT. The apoptotic cell ratio of MLT tended to be higher in lower grade lymphomas. These results suggest that EBV may participate in the malignant transformation from HT to MLT.

Malignant lymphoma of the thyroid with evidence of an Epstein-Barr viral infection concomitant with thalassemia minor: report of a case

We report herein the unusual case of a 53-year-old Japanese man in whom malignant lymphoma of the thyroid was found to coexist with asymptomatic thalassemia minor and an elevated titer (1:80) of immunoglobulin G against the Epstein-Barr viral capsid antigen. A total thyroidectomy with lymphadenectomy was performed, and the thyroid was found to be almost replaced by the neoplasm, the microscopy of which revealed malignant lymphoma of the diffuse, large-cell type. The existence of this case led us to question whether malignant lymphoma of the thyroid and an elevated titer for the Epstein-Barr virus might have a possible mutual association.

Primary non-Hodgkin's lymphoma of the thyroid with bone marrow infiltration at presentation

Primary non-Hodgkin's lymphoma of the thyroid is predominantly a disorder of elderly females. Most patients present with limited disease and receive local irradiation. Presentation with advanced disease is uncommon and, consequently, bone marrow examination is not always done. We report a patient with primary thyroid lymphoma who had bone marrow infiltration at presentation and discuss the importance of this investigation in management.

Clonality of benign lymphoid hyperplasia in orbit and conjunctiva

In order to thoroughly characterize the clonal population of lymphoid hyperplasia of the orbit and conjunctiva, we investigated six cases which were histologically proven to be benign lymphoid hyperplasia. We analyzed the clonal rearrangements of the antigen receptors and bcl-2 gene, Epstein-Barr virus (EBV), and human T-cell leukemia virus type 1 (HTLV-I) by Southern blot and/or polymerase chain reaction (PCR), and performed in situ hybridization for mRNA of kappa and lambda immunoglobulin. Five cases showed rearrangements of immunoglobulin heavy chain gene (JH) and/or light chain gene (J kappa), and the monoclonal V-J recombination of JH in PCR. However, the rearranged bands were much more faint than was the germ-line band. We considered the monoclonal population of B cells small. Two of the five cases recurred locally after four and nine years respectively. Because benign lymphoid hyperplasias frequently contain an occult monoclonal B-cell population, a follow-up should be conducted. The remaining case in our investigation showed a rearrangement of the T-cell-receptor gene and proviral DNA of HTLV-I, and it showed rapid progress to adult T-cell leukemia after the biopsy. EBV and bcl-2 gene rearrangements were not observed in any of the six cases we studied.

The pathology of autoimmune thyroid disease: a review

Lymphocytic infiltration of the thyroid gland is the pathologic hallmark of autoimmune thyroid disease. Lymphoid cells are seen in the stroma of glands affected by Graves' disease. However, large lymphoid infiltrates are characteristic of that spectrum of diseases conveniently termed chronic lymphocytic thyroiditis. In this review, the pathology of the various subtypes of chronic thyroiditis is enumerated, including recently defined lesions, i.e., painless thyroiditis, thyroiditis associated with interleukin chemotherapy, and peritumor thyroiditis are reviewed. The unifying morphologic characteristics seen in these conditions are discussed.

Thyroid lymphoma. The case for combined modality therapy

BACKGROUND

Radiation therapy with or without surgery is generally considered standard treatment for lymphoma of the thyroid. Because of the small number of cases, the role of chemotherapy or combined modality treatment is difficult to determine.

METHODS

The published literature was analyzed, supplemented by a series from Yale, for the incidence of local and distant relapse after radiation therapy, chemotherapy, or combined modality treatment for Stage I-II thyroid lymphoma. Patients with advanced disease or in whom radiation was probably inadequate were excluded. Only patients receiving an anthracyline-based regimen were considered in the group with chemotherapy. Patients receiving single agents or non-anthracycline-based regimens were excluded from analysis or, if they also received radiation, were included in the group that received radiation only.

RESULTS

Including a series from Yale, a total of 211 patients with Stage IE and IIE thyroid lymphoma were identified. Distant and overall relapse rate were significantly lower in the group that received combined modality treatment. Local relapse was also less, but the difference was not statistically significant. In a small number of patients with disease confined to the neck, the results with radiation were similar to combined modality treatment if the mediastinum was included in the treatment port.

CONCLUSION

Although mucosa-associated lymphoma tissue lymphomas are thought to have a low distant recurrence rate and are therefore often treated with local therapy alone, a review of the published literature suggests that 30% of thyroid lymphomas with clinically localized disease will have a distant relapse. The addition of chemotherapy to radiation significantly lowered distant and overall recurrence.

Fine-needle aspiration cytology diagnosis of non-Hodgkin lymphoma of thyroid: a report of four cases

Four cases of non-Hodgkin lymphoma of thyroid, diagnosed by fine-needle aspiration (FNA) cytology during a period of 3 1/2 yr constituted 0.2% of 1,716 thyroid FNAs and 3.4% of 118 thyroid neoplasms. The age of the patients ranged from 42 to 78 yr with an average of 63 yr and all were females. Three cases had thyroid swellings, and one case had cervical lymphadenopathy and fullness in the thyroid region. The lymphomas were categorized as mixed small and large cell lymphomas, large cell lymphoma, small noncleaved lymphoma (non-Burkitt-type), and plasmacytoid lymphoma. Histopathology as well as immunohistochemistry confirmed the cytodiagnosis of lymphoma in the first and fourth cases. In the second case where possibility of anaplastic carcinoma could not be ruled out altogether at initial cytologic examination, the histopathology report was undifferentiated carcinoma but immunohistochemically it was proved to be a B-cell neoplasm.

Non-Hodgkin's lymphoma of the thyroid gland: prognostic factors and treatment outcome. The Princess Margaret Hospital Lymphoma Group

PURPOSE

Non-Hodgkin's lymphoma presenting in the thyroid gland is uncommon. A review of the Princess Margaret Hospital experience was performed to assess treatment outcome and prognostic factors in this rare extranodal presentation of localized lymphoma.

METHODS AND MATERIALS

Fifty-two patients treated at the PMH between 1978 and 1986 were identified and their records reviewed retrospectively. Staging procedures revealed 16 patients with Stage I, 28 with Stage II, and eight with Stages III or IV disease. Five patients were treated on a protocol designed for anaplastic carcinoma of thyroid and they were excluded from detailed analysis. Of 39 patients with Stages I and II disease, 18 were treated with radiotherapy alone, three chemotherapy alone, and 18 combined modality therapy. Combined modality therapy was used mainly in patients with large tumor bulk.

RESULTS

The overall 5-year actuarial survival and cause-specific survival were 56% and 64%, respectively. The overall relapse-free rate was 61% at 5 years. Among the 39 patients with Stages I and II disease, the 5-year actuarial survival, cause-specific survival, and relapse-free rate were 64%, 73%, and 66%, respectively. There were no significant differences in outcome between those treated with radiotherapy alone and those treated with combined modality therapy (cause-specific survival: p = 0.25, relapse: p = 0.06). A univariate analysis showed that the only variable to reach statistical significance was tumor bulk. Age was marginally significant while stage and histology were not statistically significant, possibly due to the fairly homogeneous distribution of patients in each of these variables. Patients with progression or relapse of lymphoma after initial treatment frequently died of disease. Isolated gastrointestinal relapses occurred in three cases, representing 27% of all relapses.

CONCLUSION

Based on the above results, we recognize that the majority of patients with localized thyroid lymphoma require combined modality therapy and we recommend radiotherapy alone only for a small, select group of patients with Stage I disease and small tumor bulk.

Follicular dendritic cells in extranodal non-Hodgkin lymphomas of MALT and non-MALT type

Extranodal lymphomas of the thyroid (n = 19), kidney (n = 15) and testis (n = 30) were investigated histologically and immunohistochemically for follicular dendritic cell pattern using the monoclonal antibody Ki-FDClP. This recognizes follicular dendritic cells in paraffin sections. Follicular dendritic cells were most predominant in lymphomas of the thyroid. These thyroid lymphomas showed the morphological features of mucosa-associated lymphoid tissue (MALT) type lymphomas in 18 of 19 cases and were classified as high-grade malignant lymphoma of MALT type with evidence of a low-grade malignant component (n = 18). Ten of these cases contained destroyed reactive follicles of follicular dendritic cells. In 6 of these 10 cases follicular dendritic cells occurred in a pattern of tumour-associated abortive follicle type. The remaining lymphoma of the thyroid was an immunoblastic lymphoma of B-cell type showing no detectable follicular dendritic cells. In extranodal lymphomas of non-MALT type follicular dendritic cells occurred in only two cases where immunocytoma involved the kidney. Malignant lymphomas of the kidney (chronic lymphocytic leukaemia, n = 2; immunocytoma, n = 4; centroblastic lymphoma, n = 9) and of the testis (immunocytoma, n = 2; centroblastic lymphoma, n = 27; immunoblastic lymphoma of B-cell type, n = 1) revealed no characteristics of MALT type lymphoma, cytologically or with respect to follicular dendritic cells. Classical lymphoepithelial lesions formed by centrocyte-like cells, a hallmark of MALT, occurred exclusively in thyroid lymphomas of MALT type. Although occurrence of classical lymphoepithelial lesions formed by centrocyte-like cells was limited to thyroid lymphomas of MALT type, a growth pattern of lymphoid blasts, with formation of lesions mimicking lymphoepithelial lesions superficially, was found in 6 of 27 testicular centroblastic lymphomas. Follicular dendritic cells in non-Hodgkin's lymphomas of MALT type show distinct follicular patterns not found in other extranodal lymphomas such as those found in the kidney and testis.

Thyroid cancer

Management of thyroid cancer varies somewhat between communities and institutions depending on tumor type and individual treatment philosophy. The differentiated thyroid cancers have a significantly better outlook than the medullary and anaplastic. This article provides an overview of the literature that describes pathogenesis, diagnosis, and treatment currently recommended for these thyroid cancers.

Clinical aspects of primary thyroid lymphoma: diagnosis and treatment based on our experience of 119 cases

We describe the clinical aspects of primary thyroid lymphoma, particularly diagnostic procedures and successful therapy based on our observation of 119 patients with primary thyroid lymphoma. Thyroid lymphoma occurred exclusively in the thyroid gland of patients with Hashimoto's thyroiditis as a rapidly growing mass in the thyroid gland. Therefore, progressively enlarging goiter and compression symptoms were the most common clinical manifestations. A significant number of patients in our series had subclinical hypothyroidism (14%) or overt hypothyroidism (27%) because of the coexistence of Hashimoto's thyroiditis. Whenever thyroid lymphoma is suspected, we recommend an ultrasound scan of the thyroid gland and fine needle aspiration biopsy as initial diagnostic procedures. Thyroid ultrasound showed characteristic asymmetrical pseudocystic pattern in 43 of the 46 patients (93%), and thyroid cytologic examination showed abundant monomorphic infiltration of lymphoid cells. Among 83 patients who underwent fine needle aspiration biopsy, 65 patients (78.3%) were diagnosed correctly and 10 patients (12%) had borderline cytologic results. Thus, 90% of patients with thyroid lymphoma were diagnosed or the diagnosis suspected based on fine needle aspiration biopsy. To confirm the diagnosis of lymphoma histologically and to determine the degree of malignancy, open biopsy taking 2-3 g tissue should be done for all cases. Treatment of thyroid lymphoma does not require resection of all lymphoma tissue or total thyroidectomy. Our successful treatment is radiation therapy combined with six courses of CHOP chemotherapy (cyclophosphamide, adriamycin, vincristine, prednisolone). This mode of therapy improved the 8-year survival rate to nearly 100% regardless of the histological type of malignancy.

Immunohistochemical analysis of small cell tumors of the thyroid gland: an Eastern Cooperative Oncology Group study

The majority of small cell anaplastic tumors of the thyroid gland are generally believed to be non-Hodgkin's lymphomas, including most of those formerly classified as small cell carcinomas. Using a panel of antibodies capable of detecting epithelial, neuroendocrine, and B and T cells in paraffin-embedded tissue sections, we studied 68 thyroid neoplasms in which the original diagnosis was small cell carcinoma or lymphoma. Sixty-three of the tumors were identified as lymphomas of B-cell origin on the basis of L26 reactivity used in conjunction with light chain restriction and MB2 immunostaining. Two additional tumors were classified as lymphomas of indeterminate phenotype. Immunophenotyping indicated an epithelial origin in the remaining three tumors. No cases of medullary carcinoma were detected by immunostaining. Histologic review revealed a predominance of large cell and immunoblastic lymphomas, with low-grade lymphomas of mucosa-associated lymphoid tissue histology accounting for only five cases. Our findings indicate that the majority of small cell anaplastic tumors of the thyroid are B-cell lymphomas. Although primary small cell carcinoma of the thyroid may rarely occur, this diagnosis should not be made without immunohistologic confirmation.

Malignant Thyroid Lymphoma Presenting as Acute Airway Obstruction

Malignant thyroid lymphoma is an uncommon form of thyroid cancer which most commonly presents in elderly women. Most patients demonstrate a rapidly enlarging mass and may show tracheal deviation on chest roentgenogram. Radioisotopic scanning of the thyroid often demonstrates a “cold” or “cool” process of decreased uptake in the affected area. There is often an underlying lymphocytic thyroiditis process noted. Unfavorable prognosis is related to extracapsular extension, blood vessel wall infiltration, diffuse architectural pattern, and cervical lymph node involvement. We present two unusual cases of thyroid lymphoma presenting with acute airway obstruction and review the literature concerning this subject. One case presented a clinical and radiographic appearance similar to a prevertebral space abscess.

Nuclear morphometry of primary B cell thyroid lymphoma

Thyroid lymphoma is usually distinguished from anaplastic thyroid carcinoma and from Hashimoto's thyroiditis by morphological and immunohistochemical assessment of tissue sections. Our objective was to assess the value of nuclear morphometry in the differential diagnosis of these conditions. Nuclear area measurements were performed on 10 cases of thyroid lymphoma using an IBAS 2000 Image Analyser and compared with similar measurements performed on 10 cases of Hashimoto's thyroiditis and 2 of anaplastic thyroid carcinoma. It was found that karyometry demonstrated differences between all three conditions, the cases of thyroiditis being distinguishable from lymphoma on the basis of mean nuclear area alone. Mean nuclear area for lymphomas was greater than for Hashimoto's thyroiditis and lower than for anaplastic carcinomas. The mean nuclear area also reflected the grade of lymphoma, with the exception of one case which had a large reactive T cell population. It is concluded that nuclear morphometry provides valuable information in the diagnosis and assessment of thyroid lymphomas.

Perforation through undiagnosed small bowel involvement in primary thyroid lymphoma during chemotherapy

A case is described of fatal perforation of the small bowel through an area of undiagnosed secondary involvement from primary thyroid lymphoma during treatment by chemotherapy. There is a known association between primary thyroid lymphoma and gastrointestinal metastases. To avoid this lethal complication, a specific search should be made for gastrointestinal involvement before chemotherapy is started in patients with advanced thyroid lymphoma.

Malignant lymphoma of the thyroid: a report of two cases diagnosed by fine-needle aspiration

Two cases of primary malignant lymphoma of the thyroid were diagnosed by fine-needle aspiration biopsy. In addition to morphologic evaluation performed on direct smears, immunophenotyping, flow cytometry, and molecular studies were performed on the aspirated material. These additional studies made a clear distinction between lymphoma and Hashimoto's thyroiditis, which may present a similar cytologic picture.