Clinical Significance of Diffusely Increased Uptake of 68Ga-FAPI in Thyroid Gland

Purpose: To determine the clinical significance of diffuse uptake of 68Ga-FAPI in the thyroid.Methods: From January 2020 to September 2021, all subjects with diffuse thyroid uptake in 68Ga-FAPI PET/CT were investigated in our hospital, and compared with the age and sex matched control group. The 68Ga-FAPI uptake in the thyroid gland was analyzed semi-quantitatively using the maximum standardized uptake value (SUVmax), and regression analysis was used to analyze the correlation between available serum thyroid stimulating hormone (TSH) and thyroid peroxidase antibody (TPOAb).Results: Among 815 subjects, 39 subjects were found diffuse FAPI uptake in thyroid gland; 11 subjects refused further examination; a total of 28 subjects were included in the analysis, and 27 subjects were diagnosed with chronic thyroiditis (including 20 subjects with Hashimoto's thyroiditis), 3 subjects with Grave's disease, 3 subjects with only serum TSH elevated, and 1 subject with malignant of thyroid and thyroiditis. The SUVmax of 27 subjects with thyroiditis was 5.75 ± 5.45. No significant correlation was found between the SUVmax and the level of serum TSH (P = 0.389) or TPOAb (P = 0.426).Conclusion: The incidentally discovered diffusely increased 68Ga-FAPI uptake in the thyroid gland is mostly related to chronic lymphocytic (Hashimoto's) thyroiditis. 68Ga-FAPI uptake level correlated neither with the degree of hypothyroidism nor with the titer of TPOAb. In addition, immune-related thyroiditis with immune checkpoint inhibitors may be accidentally found on 68Ga-FAPI, which may be helpful in facilitate timely intervention.

Chronic thyroiditis in lateral ectopic thyroid mimicking cervical metastasis of thyroid cancer

Summary We present the case of a 45-year-old Caucasian woman who attended the Endocrinology Unit for a left cervical mass discovered during follow-up for autoimmune chronic thyroiditis. The ultrasound-guided fine-needle aspiration biopsy of the lesion was consistent with a metastasis of follicular thyroid carcinoma. The sonographic neck evaluation revealed no thyroid nodules but three markedly hypoechoic and highly vascularized areas, with irregular margins and hyperechoic spots. In the clinical suspicion of primary thyroid neoplasm, ultrasound-guided fine-needle aspiration biopsy of two of the three areas was performed, but both cytological reports were non-diagnostic, revealing only colloid and blood. Subsequently, the patient underwent surgical removal of the cervical mass, with the intra-operatory consultation with frozen section examination suggesting follicular-like neoplasia. For this reason, thyroidectomy with both central and lateral neck dissection was performed. Surprisingly, the final histologic examination revealed chronic thyroiditis in the thyroid specimen and no evidence of metastasis in the left neck mass. Consequently, the pathological revision of the frozen section assessment led to the final diagnosis of chronic thyroiditis on the lateral ectopic thyroid. This case represents an uncommon example of lateral ectopic thyroid tissue with coexisting normally located thyroid tissue both affected by chronic thyroiditis. Learning points Ectopic thyroid must be considered in the diagnostic work-up of lateral neck mass. Even if rare, ectopic thyroid tissue can be found lateral to the carotid sheath and with coexisting normally located thyroid tissue. As the orthotopic tissue, lateral ectopic thyroid tissue can be affected by chronic thyroiditis, which may complicate the diagnosis both on ultrasound and cytology.

Clinical practice guidelines for acute and chronic thyroiditis (excluding autoimmune thyroiditis)

Acute and chronic thyroid diseases are the most frequently detected disorders being second only to diabetes mellitus.The World Health Organization points out that thyroid diseases’ incidence tends to grow every year. The present paper consists of clinical practice guidelines that consider etiology, clinical course, diagnostics and treatment of acute and chronic inflammatory thyroid diseases (except those of autoimmune type).The clinical practice guidelines provide an important working tool for clinicians including specialty physicians and medical experts. Containing structured and concise information on the specific nosology, diagnostic methods and treatment tips these guidelines allow medical specialists to quickly resolve difficulties and choose the most efficient and personalized treatment (following strict principles of evidence-based medicine at the same time).The clinical practice guidelines were drawn up by highly-skilled professional team of specialty physicians approved by the Expert Council of Russian Federation’s Health Department. These guidelines contain the most complete and up-to-date information required to diagnose acute and chronic thyroiditis, provide patient care and treatment.The working group publishes the present paper in the professional journal dealing with endocrinology topics to improve healthcare quality and refine treatment of acute and chronic thyroiditis (autoimmune thyroiditis excluded). It is advisable to acquaint as many endocrinology and general (family) medicine specialists as possible with the full text of these clinical guidelines.

DNA repair proteins may differentiate papillary thyroid cancer from chronic lymphocytic thyroiditis and nodular colloidal goiter

Malignant thyroid lesions are the most common malignancy of the endocrine glands with increasing rates in the last two decades. Papillary thyroid cancer is the most common thyroid malignancy. In our study, we aimed to quantitatively evaluate the levels of DNA repair proteins MSH2, MLH1, MGMT, which are representative blocks of patients diagnosed with papillary carcinoma, chronic thyroiditis, or colloidal goiter. Total or subtotal thyroidectomy material of 90 patients diagnosed with papillary carcinoma, nodular colloidal goiter, or chronic thyroiditis between 2009 and 2012 were retrospectively evaluated. Tissue samples obtained from paraffin blocks were stained with MGMT, MSH2, MLH1 proteins and their immunohistochemistry was evaluated. Prepared sections were examined qualitatively by an impartial pathologist and a clinician, taking into account the staining method under the trinocular light microscope. Although there was no statistically significant difference in MGMT, MSH2, MLH1, follicular cell positivity, staining intensity, and immunoreactivity values, papillary carcinoma cases showed a higher rate of follicular cell positivity, and this difference was more pronounced between papillary carcinoma and colloidal goiter. In the MSH2 follicular cell positivity evaluation, the difference between chronic thyroiditis and colloidal goiter was significant (p = 0.023). The difference between chronic thyroiditis and colloidal goiter was significant in the MSH2 staining intensity evaluation (p = 0.001). The difference between chronic thyroiditis and colloidal goiter was significant in MLH1 immunoreactivity evaluation (p = 0.012). Papillary carcinoma cases were demonstrated by nuclear staining only for MSH2 and MLH1 proteins as opposed to hyperplastic nodules. The higher levels of expression of DNA repair genes in malignant tumors compared to benign tumors are attributed to the functional activation of DNA repair genes. Further studies are needed for DNA repair proteins to be a potential test in the development and progression of thyroid cancer.

Sarcoidosis-Lymphoma Syndrome Associated With Primary Thyroid Lymphoma: A Case Report

Background: Sarcoidosis is occasionally accompanied by hematologic malignancies, including lymphoma, called sarcoidosis-lymphoma syndrome. Although the mechanism underlying the induction of lymphomas is still unknown, understanding the immunological background of sarcoidosis could help explain the possible mechanisms of the induction of lymphomas. Case Presentation: A 52-year-old woman was diagnosed chronic thyroiditis with normal thyroid function. One year later, she underwent a screening chest radiograph and identified bilateral hilar adenopathy and mediastinum lymphadenopathy. Subsequent mediastinoscopy demonstrated sarcoidosis. Because of the lack of clinical symptoms, steroid treatment was not initiated and regular follow-up was performed. One and a half years after the diagnosis of chronic thyroiditis, she presented with rapid swelling of the thyroid gland. FDG-PET/CT showed intense uptake of FDG in the thyroid gland and multiple lymphadenopathy. Fine-needle aspiration (FNA) cytology of the thyroid gland was only suggestive of a lymphoproliferative disorder and did not provide a definitive diagnosis. Partial thyroidectomy was performed, and the pathology indicated diffuse large B-cell lymphoma (DLBCL) such as high-grade transformation of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma. The results of an examination of a paraffin block histopathology specimen by fluorescence in-situ hybridization (FISH) detected BCL6 rearrangement (3q27), which is the most common chromosomal abnormality in DLBCL. After the treatment with R-EPOCH (rituximab, etoposide, vincristine, doxorubicin, cyclophosphamide, and prednisone) chemotherapy, the thyroid gland enlargement has improved markedly, while the lymph nodes remained swelling, that suggested lymph node involvements were due to sarcoidosis. Conclusions: Rapid swelling of the thyroid gland in the setting of chronic thyroiditis should raise suspicion for thyroid lymphoma. Furthermore, our present case might suggest that sarcoidosis accelerate the development and high-grade transformation of thyroid lymphoma. To our knowledge, this is the first reported case of sarcoidosis and primary thyroid lymphoma in the same patient.

The Utility of 18F-Fluorocholine PET/CT in The Imaging of Parathyroid Adenomas

Aim: to estimate sensitivity of 18F-FCH PET/CT in preoperative localisation of hyperfunctioning parathyroid glands in patients with primary hyperparathyroidism (PHPT). Methods: 65 consecutive patients with PHPT who underwent neck ultrasound (US) and 99mTc/99mTc-MIBI dual-phase parathyroid scintigraphy were prospectively enrolled. Twenty-two patients had unsuccessful parathyroid surgery prior to the study. PET/CT scans were performed 65.0 ± 13.3 min after injection of 218.5 ± 31.9 MBq of 18F-fluorocholine (FCH). Three experienced nuclear medicine physicians assessed the detection rate of hyperfunctioning parathyroid tissue. Response to parathyroidectomy and clinical follow-up served as a reference test. Per-patient sensitivity and positive predictive value (PPV) were calculated for patients who underwent surgery.Results: 18F-FCH PET/CT was positive in 61 patients, and negative in four. US and parathyroid scintigraphy showed positive and negative results in 20 , 45 and 17, 48, respectively. US showed nodular goiter in 31 patients and chronic thyroiditis in 9 patients. Parathyroid surgery was performed in 43 (66%) patients. 18F-FCH PET/CT yielded sensitivity of 100% (95% CI [87.99-100]) and PPV of 85.7% (95% CI [70.77-94.06]). Similar values were observed in patients with chronic thyroiditis, nodular goiter, and patients after an unsuccessful parathyroid surgery. PET/CT identified hyperparathyroidism complications (kidney stones, osteoporotic bone fractures and brown tumours) in 11 patients.Conclusions: 18F-FCH PET/CT effectively detected hyperfunctioning parathyroid tissue and its complications. The method showed excellent sensitivity and positive predictive value, including patients with nodular goiter, chronic thyroiditis and prior unsuccessful parathyroidectomy. PET/CT performance was superior to neck ultrasound and parathyroid scintigraphy.

Thyroid and COVID-19: a review on pathophysiological, clinical and organizational aspects

BackgroundThyroid dysfunction has been observed in patients with COVID-19, and endocrinologists are requested to understand this clinical issue. Pandemic-related restrictions and reorganization of healthcare services may affect thyroid disease management.Objective and methodsTo analyze and discuss the relationship between COVID-19 and thyroid diseases from several perspectives. PubMed/MEDLINE, Google Scholar, Scopus, ClinicalTrial.gov were searched for this purpose by using free text words and medical subject headings as follows: “sars cov 2”, “covid 19”, “subacute thyroiditis”, “atypical thyroiditis”, “chronic thyroiditis”, “hashimoto’s thyroiditis”, “graves’ disease”, “thyroid nodule”, “differentiated thyroid cancer”, “medullary thyroid cancer”, “methimazole”, “levothyroxine”, “multikinase inhibitor”, “remdesivir”, “tocilizumab”. Data were collected, analyzed, and discussed to answer the following clinical questions: “What evidence suggests that COVID-19 may induce detrimental consequences on thyroid function?"; "Could previous or concomitant thyroid diseases deteriorate the prognosis of COVID-19 once the infection has occurred?”; “Could medical management of thyroid diseases influence the clinical course of COVID-19?”; “Does medical management of COVID-19 interfere with thyroid function?”; “Are there defined strategies to better manage endocrine diseases despite restrictive measures and in-hospital and ambulatory activities reorganizations?”.ResultsSARS-CoV-2 may induce thyroid dysfunction that is usually reversible, including subclinical and atypical thyroiditis. Patients with baseline thyroid diseases are not at higher risk of contracting or transmitting SARS-CoV-2, and baseline thyroid dysfunction does not foster a worse progression of COVID-19. However, it is unclear whether low levels of free triiodothyronine, observed in seriously ill patients with COVID-19, may worsen the disease's clinical progression and, consequently, if triiodothyronine supplementation could be a tool for reducing this burden. Glucocorticoids and heparin may affect thyroid hormone secretion and measurement, respectively, leading to possible misdiagnosis of thyroid dysfunction in severe cases of COVID-19. High-risk thyroid nodules require a fine-needle aspiration without relevant delay, whereas other non-urgent diagnostic procedures and therapeutic interventions should be postponed.DiscussionCurrently, we know that SARS-CoV-2 could lead to short-term and reversible thyroid dysfunction, but thyroid diseases seem not to affect the progression of COVID-19. Adequate management of patients with thyroid diseases remains essential during the pandemic, but it could be compromised because of healthcare service restrictions. Endocrine care centers should continuously recognize and classify priority cases for in-person visits and therapeutic procedures. Telemedicine may be a useful tool for managing patients not requiring in-person visits.

Malignancy in Clinically Non-toxic Multinodular Goiter

Objective: Goiter is a common form of thyroid swelling among population living in areas of iodine deficiency. Of the goiters, non-toxic multinodular goiter (MNG) is the most common and benign form of thyroid disease. However, studies have shown that long-standing MNGs may harbour malignancy. The present study was, therefore, undertaken to ascertain the prevalence of malignancy in clinically diagnosed non-toxic MNGs. Methods: This cross-sectional study was conducted in the Department of Surgery (all four-units) and ENT Department, Rajshahi Medical College Hospital, Rajshahi from July 2007 to June 2008 on 100 patients of clinically non-toxic MNG who underwent thyroid surgery. Biopsy materials were taken from the excised nodules and were sent for histopathological examination to see what proportion of them harboured malignancy. Result: The findings of the study showed that 40% of patients were 30-40 years old with mean age of the patients being 35.5 ± 10.1 (range: 14-75) years. Majority (87%) of the patients was female. Half of the patients with non-toxic MNGs had a history of thyroid swelling for 1-5 years and the rest half for > 5 years with median duration of illness being 5.5 years (range: 1-30 years). Of the 100 patients 4% had stridor and 6% dyspnoea; dysphagia and cervical lymphadenopathy each was 6%. Nearly 60% of the patients had goiter of size 15 sq-cm or below. Sub-total thyroidectomy was the most common operation performed (33%) followed by right hemi-thyroidectomy (24%), near total thyroidectomy (20%), left hemi-thyroidectomy (18%) and total thyroidectomy (5%). Histopathological examination of resected specimens revealed that 15% of the MNGs had malignancy with papillary to follicular carcinoma ratio being 4:1. Histopathological typing showed that 79% was simple MNGs, 4% follicular adenoma, 12% papillary carcinoma, 3% follicular carcinoma and 2% chronic thyroiditis. Neither age nor sex was found to be associated with presence of malignancies in MNGs (p = 0.865 and p = 0.647 respectively). The goiter-size was also not associated with presence of malignancies (p = 0.691). However, the mean duration of thyroid swelling in patients who had malignancy was much higher (8.5 years) than that in patients who did not haveany malignancy (5.7 years) (p = 0.024). Conclusion: The study concluded that a small proportion of long-standing non-toxic MNGs may turn into malignancy. Therefore, routine operative treatment without confirming that the cases are malignant does not seem to be justified. Ibrahim Card Med J 2020; 10 (1&2): 84-88