Rare Thyroid Malignancies: an Overview for the Oncologist

Thyroid liposarcoma: a case report

Objectives

Thyroid liposarcoma is a rare tumor. Its low prevalence accounts for the scarcity of data in the literature, which consists mostly of small studies and case reports.

Case presentation

We present the case of a 60 years old male with no past medical or past surgical history and presented with neck discomfort and a large left thyroid nodule. Thyroid ultrasound and CT scan were performed and confirmed the existence of a thyroid nodule most probably inside the left inferior thyroid lobe. In the posterior mediastinum, two fatty formations were found. To complete, an MRI was performed, showing a mixed lesion, of the lower neck and upper chest. The patient underwent an extended resection which consisted of an en bloc resection of the lesion (left thyroid lobectomy and isthmus resection) by an anterior transverse cervical incision and a sternotomy. Tracheal and laryngeal shaving and esophageal shaving with resection of the esophageal muscularis was performed as well. The pathological evaluation of the specimen showed a grade II dedifferentiated liposarcoma with an inflammatory component.

Conclusions

Thyroid liposarcoma is a rare lesion of the thyroid. Its management requires an exhaustive workup followed by an en bloc resection of the lesion. Depending on the histology, postoperative radiation therapy may or may not be necessary.

Vitamin D-Related Genes and Thyroid Cancer-A Systematic Review

Vitamin D, formerly known for its role in calcium-phosphorus homeostasis, was shown to exert a broad influence on immunity and on differentiation and proliferation processes in the last few years. In the field of endocrinology, there is proof of the potential role of vitamin D and vitamin D-related genes in the pathogenesis of thyroid cancer-the most prevalent endocrine malignancy. Therefore, the study aimed to systematically review the publications on the association between vitamin D-related gene variants (polymorphisms, mutations, etc.) and thyroid cancer. PubMed, EMBASE, Scopus, and Web of Science electronic databases were searched for relevant studies. A total of ten studies were found that met the inclusion criteria. Six vitamin D-related genes were analyzed (VDR-vitamin D receptor, CYP2R1-cytochrome P450 family 2 subfamily R member 1, CYP24A1-cytochrome P450 family 24 subfamily A member 1, CYP27B1-cytochrome P450 family 27 subfamily B member 1, DHCR7-7-dehydrocholesterol reductase and CUBN-cubilin). Moreover, a meta-analysis was conducted to summarize the data from the studies on VDR polymorphisms (rs2228570/FokI, rs1544410/BsmI, rs7975232/ApaI and rs731236/TaqI). Some associations between thyroid cancer risk (VDR, CYP24A1, DHCR7) or the clinical course of the disease (VDR) and vitamin D-related gene polymorphisms were described in the literature. However, these results seem inconclusive and need validation. A meta-analysis of the five studies of common VDR polymorphisms did not confirm their association with increased susceptibility to differentiated thyroid cancer. Further efforts are necessary to improve our understanding of thyroid cancer pathogenesis and implement targeted therapies for refractory cases.

Prognostic Role of Pre-Treatment [18F]FDG PET/CT in Patients with Anaplastic Thyroid Cancer

Simple Summary

This study evaluates the prognostic capability of the ¹⁸fluorodeoxyglucose ([¹⁸F]FDG) positron emission tomography (PET)/computed tomography (CT) in patients with anaplastic thyroid cancer (ATC) which can be used as a potential biomarker reflecting glycolysis. ATC is a rare, but highly lethal disease with a one-year overall survival of 20%, and its prognostic factors have rarely been investigated. In this study, survival data correlated with PET/CT derived parameters provide evidence that FDG uptake assessed by PET/CT is a prognostic marker, which may have a clinical impact on the management of patients with ATC.

Abstract

Anaplastic thyroid carcinoma (ATC) is a rare but highly lethal disease. Therefore, its diagnosis at an early stage and a rapid and accurate establishment of a proper treatment strategy is warranted. Tumor glycolysis assessed by ¹⁸fluorodeoxyglucose ([¹⁸F]FDG) positron emission tomography (PET)/computed tomography (CT) is predictive of many cancers despite its limited proven applicability to ATC. We investigated the prognostic capability of [¹⁸F]FDG PET/CT in patients with ATC. Forty patients with ATC were subjected to [¹⁸F]FDG PET/CT for pre-treatment evaluation. The tumor size and stage, overall survival (OS), and PET parameters, including the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were analyzed. The 1-year OS rate was 17.5% with a mean life expectancy of 7.1 months. Distant metastasis was detected solely using PET/CT in 37.5% of cases. High SUVmax, MTV, and TLG were significantly associated with poor prognosis (p < 0.001, p = 0.002, and p < 0.001, respectively). A significant difference (p < 0.001) was observed in OS between patients with a high and low tumor SUVmax. Glucose metabolism assessed by [¹⁸F]FDG PET/CT was significantly associated with the OS of patients with ATC. PET-derived parameters such as SUVmax, MTV, and TLG are useful prognostic biomarkers for ATC.

PET/Computed Tomography in Thyroid Cancer

Primary thyroid cancers demonstrate distinct biological behaviors depending on their histologic characteristics. The ability to accumulate radioiodine by differentiated thyroid cancer cells is lost in primary aggressive, poorly differentiated and dedifferentiated tumor cells. PET imaging comes into play in these challenging situations where it can provide additive information to radioiodine scintigraphy and conventional imaging. This review focuses on the current guidelines and future prospects of PET imaging in thyroid cancers.

Progressively Enlarging Goiter: Case Reports of Primary Thyroid Lymphoma and Literature Review

Primary thyroid lymphoma (PTL) is an exceptionally rare and highly aggressive potentially curable malignant disease. We report three typical cases of PTL referred to our hospital. All three cases had long history of Hashimoto's thyroiditis, and presented with progressively enlarging neck mass. The first two cases were confirmed by surgical biopsy to be diffuse large B cell lymphoma, and received radiotherapy combined with chemotherapy, or received only chemotherapy. The third case was confirmed by core needle biopsy to be mucosa-associated lymphoid tissue lymphoma, and received radiotherapy. In summary, confirmation of PTL diagnosis is essential for further clinical decisions. Core biopsy should be one of the most important methods to make the diagnosis of PTL, while the use of fine needle aspiration cytology alone is still limited in diagnosing PTL.

Undifferentiated pleomorphic sarcoma of the thyroid: A case report and ƚiterature review

This report describes a patient who presented with a large thyroid nodule and compressive symptoms. Immunohistochemical staining showed diffuse marked reactivity for vimentin and focal reactivity for CD68 and Ki-67 that is compatible with primary undifferentiated pleomorphic sarcoma of the thyroid. This report emphasizes and discusses extremely rare thyroid cancer type.

Thyroid cancer management: from a suspicious nodule to targeted therapy

Thyroid nodules are very common, and their frequency is four to five times higher in women than in men. Most of them are benign, with only a very little percentage revealing a malignant neoplasm. About 50% of thyroid nodules are detected by self-palpation of neck, whereas the other 50% are diagnosed by neck ultrasonography and following fine-needle aspiration. Management of thyroid nodules is very difficult, because benign nodules are prevalent, whereas thyroid carcinoma is uncommon, representing only 1% of all malignancies. A standard diagnostic approach is represented by 'first-level' exams, consisting in neck ultrasonography and serum thyroid-stimulating hormone measurement, followed, only for nodules that are suspicious of malignancy, by 'second-level' exams, consisting of fine-needle aspiration and mutational test, which does detect particular DNA mutations present only in malignant cells. In this review, we will analyze the genetics of thyroid cancer and its heterogeneity, and we will briefly describe the current available diagnostic and therapeutic approaches.

JAK/STAT3 and NF-κB Signaling Pathways Regulate Cancer Stem-Cell Properties in Anaplastic Thyroid Cancer Cells

Background: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive and refractory cancers, and a therapy with a new concept needs to be developed. Recently, research on cancer stem cells (CSCs) has progressed, and CSCs have been suggested to be responsible for metastasis, recurrence, and therapy resistance. In ATC-CSCs, aldehyde dehydrogenase (ALDH) activity is the most reliable marker to enrich CSCs. However, it is just a marker and is not involved in CSC properties. The present study therefore aimed to identify key signaling pathways specific for ATC-CSCs. Methods: A small interfering RNA library targeting 719 kinases was used in a sphere formation assay and cell survival assay using ATC cell lines to select target molecules specific for CSC properties. The functions of the selected candidates were confirmed by sphere formation, cell survival, soft agar, and nude mice xenograft assays using small compound inhibitors. Results: The study focused on PDGFR, JAK, and PIM, whose small interfering RNAs had a higher inhibitory effect on sphere formation, as well as a lower or no effect on regular cell growth in both FRO and KTC3 cells. Next, inhibitors of PDGFR, JAK, STAT3, PIM and NF-κB were used, and all of them successfully suppressed sphere formation in a dose-dependent manner but not regular cell growth, confirming the screening results. Inhibition of the JAK/STAT3 and NF-κB pathways also reduced anchorage-independent growth in soft agar and tumor growth in nude mice. Conclusions: These results suggest that JAK/STAT3 and NF-κB signals play important roles in ATC-CSCs. Targeting these signaling pathways may be a promising approach to treat ATC.

A Review of Primary Thyroid Lymphoma: Molecular Factors, Diagnosis and Management

Purpose/aim: To focus on current aspects of primary thyroid lymphoma (PTL), which is a rare clinical entity usually manifested by a rapidly growing mass in the neck that can cause pressure symptoms.

MATERIALS AND METHODS

Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.

RESULTS

The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.

CONCLUSIONS

A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level.

Features and trends of thyroid cancer in patients with thyroidectomies in Beijing, China between 1994 and 2015: a retrospective study

OBJECTIVES

This study aims to summarise the features and trends of thyroid carcinoma in the past two decades in China.

DESIGN, SETTING AND PARTICIPANTS

Clinical data obtained from 10 798 patients treated by thyroidectomy from 1994 to 2015 at the Department of General Surgery of the People's Liberation Army General Hospital, Beijing, China were retrospectively analysed.

OUTCOME MEASURES

Incidence and histopathological features of thyroid cancer were compared and the risk factors for local lymph node metastasis analysed.

RESULTS

Our data indicated a significant increase in the detection of thyroid cancer (from 16.8% to 69.8%, p<0.01). Among the 5235 thyroid cancer cases, papillary thyroid carcinoma (PTC) was the most common histotype, accounting for 95.1% of all malignancies over the 22-year period. Among the 4979 PTCs, micro-PTCs (mPTC) with the largest diameter ≤10 mm has gradually become the dominant form, and its percentage in PTCs has increased from 13.3% in the biennial period of 1994-1995 to 51.2% in 2010-2011. Furthermore, the size of the tumour has decreased significantly from 2.3±1.1 cm in 1994 to 1.2±0.9 cm in the largest diameter (p<0.01), while the average age at diagnosis and female dominance remained unchanged during the period. Logistic regression showed that tumour nodules>1 cm and male gender were the main risk factors for local lymph node metastasis (LNM), whereas patients over 45 years had lower risk.

CONCLUSIONS

During the 22-year period, an increased detection of thyroid cancer, particularly mPTC, was found while the occurrence of LNM decreased. Our results suggest that the current preoperative diagnosis and risk stratification are adequate, supporting the published guidelines for the diagnosis of thyroid cancer.

Coexistence of medullary thyroid carcinoma and recurrent non-functional pituitary adenoma: a case report

Background

Medullary thyroid carcinoma and pituitary adenoma are neuroendocrine tumors and their coexistence has not been reported in the literature, previously. Medullary thyroid carcinoma is a neoplasm of the thyroid gland arising from parafollicular c-cells producing calcitonin, and pituitary adenoma is a benign hyperplasia of the cells of the pituitary gland. Coexistence of these neoplasms can be explained by being affected by simultaneous primary neoplasms or tumor-to-tumor metastasis phenomenon.

Case presentation

We present the case of a 60-year-old Persian man who presented to the clinic with a chief complaint of headache for the last 2 months. His past medical history was significant for non-functional pituitary macroadenoma and medullary thyroid carcinoma and he had received a total thyroidectomy and a transsphenoidal surgery several years ago. Diagnostic evaluations revealed that the pituitary adenoma has recurred. He was well and symptom-free after the second transsphenoidal surgery for resection of the adenoma. Noticeably, investigations were negative for any form of multiple endocrine neoplasia syndromes; however, we could not rule them out definitively.

Conclusions

To the best of our knowledge, it is the first case reported in the literature of a patient who has been affected by recurrent non-functional pituitary adenoma and medullary thyroid carcinoma, concomitantly. Although this association can be accidental, it emphasizes the fact that patients with a history of a neoplasm should be monitored regularly in order to diagnose and treat possible second primary cancers in a timely manner. Of note, this consideration is of great importance in patients whose first neoplasms have better prognosis and survival rates, which provide them more time to develop second primary cancers, for example, pituitary adenoma.

Optimal combination of treatment modality to increase survival in patients with anaplastic thyroid carcinoma: A STROBE compliant retrospective study

There is little consensus on the optimal treatment approach for newly diagnosed patients. The present study aims to provide additional evidence by evaluating a series of patients diagnosed with anaplastic thyroid carcinoma (ATC) and analyzing factors related to increased survival. This was a retrospective cohort report structured according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guideline. Demographics, chief complaint, history of prior thyroid cancer, stage at presentation, management modalities (surgery, chemotherapy, radiotherapy, or observation), completeness or resection, and survival period since initial diagnosis were reviewed for patients with documentation of histologic ATC diagnosis between 2003 and 2016. The median survival period for 34 patients (11 males, 23 females) was 93.5 days. Patients aged 70 or younger (111 days) tended to survive longer than those older 70 (88 days) (P = .081). Observation, surgery only, radiotherapy only, and chemo-radiotherapy after surgery group showed median survival of 88 days, 49 days (range 14-528), 61.5 days, and 225 days, respectively. There was also no significant difference in survival between the 10 (29.4%) stage IVb (225 days) and 23 (67.7%) IVc (88 days) patients (P = .242). The median survival of the R1 resection group was 514 days while that of the R2 group was 102 days (P = .338). There were no significant difference between patients with the de novo ATC (112 days) and patients with papillary thyroid carcinoma origin ATC (99 days) (P = .297). Results from our series of 34 patients with ATC show that more intense combination of surgery and chemo-radiotherapy tends to secure a longer survival period. Therefore we recommend a multi-modality approach after a comprehensive consultation with the patient.

Liposarcoma of the Thyroid: A Case Report with a Review of the Literature

BACKGROUND

Liposarcomas of the thyroid gland are extremely rare tumors, and, to our knowledge, only 12 cases have been reported in the English literature. An accurate diagnosis is challenging due to the nonspecific clinical presentation of this cancer, frequently defined just by a swelling of the neck.

PATIENT FINDINGS

We present an 82-year-old woman with liposarcoma of the thyroid, complaining of a fast-growing neck mass. MRI and neck ultrasound showed a large lipomatous mass, which corresponded to a cold nodule in the thyroid scan. After performing a total thyroidectomy, the diagnosis of a well-differentiated liposarcoma of the thyroid gland was made, showing an MDM2 amplification in fluorescence in situ hybridization. Since neither a metastasis nor a residual tumor was found, no further adjuvant therapy was needed.

RESULTS

We searched the literature for previous case reports and identified only 12 cases worldwide to form our database. A demographic as well as clinical and histopathological analysis was made. In most cases, the liposarcoma occurred in patients >60 years of age. All histological subtypes, such as well-differentiated and myxoid liposarcomas, and pleomorphic and dedifferentiated liposarcomas, were found in the literature. In only 38.46% of the cases, an infiltration of the adjacent organs was observed. Surgery was the most common treatment chosen.

CONCLUSIONS

Our review provides clinical and histopathological features of a primary liposarcoma of the thyroid to enable the identifi-cation of this rare tumor entity and assist in the decision-making process regarding therapeutic options and tumor follow-up.

When should genetic testing be performed in patients with neuroendocrine tumours?

Neuroendocrine tumours (NETs) are a heterogenous group of tumours arising from neuroendocrine cells in several sites around the body. They include tumours of the gastroenteropancreatic system, phaeochromocytoma and paraganglioma and medullary thyroid cancer. In recent years, it has become increasingly apparent that a number of these tumours arise as a result of germline genetic mutations and are inherited in an autosomal dominant pattern. The number of genes implicated is increasing rapidly. Identifying which patients are likely to have a germline mutation enables clinicians to counsel patients adequately about their future disease risk, and allows for earlier detection of at-risk patients through family screening. The institution of screening and surveillance programmes may in turn lead to a major shift in presentation patterns for some of these tumours. In this review, we examine the features which may lead a clinician to suspect that a patient may have an inherited cause of a NET and we outline which underlying conditions should be suspected. We also discuss what type of screening may be appropriate in a variety of situations.