Retrospective Analysis of PSMA PET/CT Thyroid Incidental Uptake in Adults: Incidence, Diagnosis and Treatment/outcome in a Tertiary Cancer Referral Center and an Academic Hospital

Purpose A prostate-specific membrane antigen (PSMA) thyroid incidentaloma (PTI) is an unexpected, PSMA-avid thyroid lesion, newly detected during the investigation of an unrelated condition using PSMA PET/CT. The aim of this study is to examine the incidence and clinical significance of PTI and the associated management strategies since the implementation of the PSMA PET/CT scan. Methods This study involves a retrospective cohort study of 61 PTI cases depicted on PSMA PET/CT scans performed between January 2016 and July 2021, almost exclusively for (re)staging prostate cancer. The medical records of the included cases were retrospectively reviewed and data of the PSMA PET/CT scans, primary malignancy, thyroid diagnostics, treatment and follow-up were collected. Results PTI was reported in 1.1% of the oncologic PSMA PET/CT scans included in this study. Two PTI cases had a histologically proven thyroid cancer, one a benign thyroid lesion and one a metastasis of a renal cell carcinoma. In none of the cases in whom any form of further thyroid work-up was withheld, the PTI became clinically relevant during follow-up (median 1.8 years (1.1-3.3)). Six patients (10%) died due to their primary cancer.Conclusion The incidence of thyroid incidentalomas on PSMA PET/CT was low (1.1%) in this large, two-center experience. Less than half of the PTI cases were analyzed and the risk of malignancy, despite being low, was not negligible. The clinical outcome was good using a standard diagnostic work-up for PTI, while the prognosis of the patient was determined by the primary malignancy. The consideration to analyze and treat PTI cases should be part of the shared decision making in cancer patients.

Radiomics analysis improves 18FDG PET/CT-based risk stratification of cytologically indeterminate thyroid nodules

Purpose As ~25% of cytologically indeterminate thyroid nodules harbour malignancy, diagnostic lobectomy is still performed in many cases. 18FDG PET/CT rules out malignancy in visually negative nodules; however, none of the currently available interpretation criteria differentiates malignant from benign 18FDG-avid nodules. We evaluated the ability of PET metrics and radiomics features (RFs) to predict final diagnosis of 18FDG-avid cytologically indeterminate thyroid nodules. Methods Seventy-eight patients were retrospectively included. After volumetric segmentation of each thyroid lesion, 4 PET metrics and 107 RFs were extracted. A logistic regression was performed including thyroid stimulating hormone, PET metrics, and RFs to assess their predictive performance. A linear combination of the resulting parameters generated a radiomics score (RS) that was matched with cytology classes (Bethesda III and IV) and compared with final diagnosis. Results Two RFs (shape_Sphericity and glcm_Autocorrelation) differentiated malignant from benign lesions. A predictive model integrating RS and cytology classes effectively stratified the risk of malignancy. The prevalence of thyroid cancer increased from 5 to 37% and 79% in accordance with the number (score 0, 1 or 2, respectively) of positive biomarkers. Conclusions Our multiparametric model may be useful for reducing the number of diagnostic lobectomies with advantages in terms of costs and quality of life for patients.

Radiomics analysis improves 18FDG PET/CT-based risk stratification of cytologically indeterminate thyroid nodules

Purpose As ~ 25% of cytologically indeterminate thyroid nodules harbour malignancy, diagnostic lobectomy is still performed in many cases. 18FDG PET/CT rules out malignancy in visually negative nodules; however, none of the currently available interpretation criteria differentiates malignant from benign 18FDG-avid nodules. We evaluated the ability of PET metrics and radiomics features (RFs) to predict final diagnosis of 18FDG-avid cytologically indeterminate thyroid nodules. Methods 78 patients were retrospectively included. After volumetric segmentation of each thyroid lesion, 4 PET metrics and 107 RFs were extracted. A logistic regression was performed including thyroid stimulating hormone, PET metrics and RFs to assess their predictive performance. A linear combination of the resulting parameters generated a radiomics score (RS) that was matched with cytology classes (Bethesda III and IV) and compared with final diagnosis. Results Two RFs (shape_Sphericity and glcm_Autocorrelation) differentiated malignant from benign lesions. A predictive model integrating RS and cytology classes effectively stratified the risk of malignancy. The prevalence of thyroid cancer increased from 5–37% and 79% in accordance with the number (score 0, 1 or 2, respectively) of positive biomarkers. Conclusion Our multiparametric model may be useful for reducing the number of diagnostic lobectomies with advantages in terms of costs and quality of life for patients.

A Descriptive Study of Cytomorphological Grading of Hashimoto’s Thyroiditis and Its Association with Thyroid Hormone Profile in a Tertiary Care Center in Mandya, Karnataka

BACKGROUND Thyroid diseases are the most common endocrine disorders throughout the world. Hashimoto’s thyroiditis is an autoimmune thyroid disorder and it is the second most common thyroid lesion diagnosed on fine needle aspiration cytology (FNAC), only after goiter. FNAC is a quick, easy, safe, cost-effective and highly sensitive investigation for diagnosing Hashimoto’s thyroiditis. The cytomorphological grading of Hashimoto’s thyroiditis was 1st done by Bhatia et al. in 1912. The purpose of this study was to grade Hashimoto’s thyroiditis cytomorphologically according to lymphocytic infiltration and correlating it with thyroid hormone profile. METHODS This is a descriptive study of 87 cases which were diagnosed with Hashimoto’s thyroiditis from January 2019 to December 2019 at the Cytopathology, Department of Pathology, MIMS, Mandya. The slides were collected, reviewed and graded according to Bhatia et al.’s grading system. Thyroid hormone values were collected from the department of biochemistry. The association between cytological grades and thyroid hormone parameters such as T3, T4, TSH and antithyroid peroxidase (anti-TPO) antibody were evaluated. RESULTS In our study, female preponderance was noted. The age range in our study was 10 - 64 years and the majority of cases were in the age group of 21 - 40 years. Grade II was the most common cytological grade, followed by grade III. Based on thyroid function values, majority of the cases were hypothyroid, followed by euthyroid and remaining were hyperthyroid. Anti-TPO levels was raised in 80.6 %, most of them had hypothyroidism. CONCLUSIONS In our study, there was no statistical association between cytological grades and thyroid hormone status. KEYWORDS Hashimoto’s Thyroiditis, FNAC, Bhatia et al.’s Grading, Anti-TPO Antibodies, fT3, fT4, Immunoassay Analyzer

A Personalized 3D-Printed Model for Obtaining Informed Consent Process for Thyroid Surgery: A Randomized Clinical Study Using a Deep Learning Approach with Mesh-Type 3D Modeling

The aim of this study was to evaluate the usefulness of a personalized 3D-printed thyroid model that characterizes a patient’s individual thyroid lesion. The randomized controlled prospective clinical trial (KCT0005069) was designed. Fifty-three of these patients undergoing thyroid surgery were randomly assigned to two groups: with or without a 3D-printed model of their thyroid lesion when obtaining informed consent. We used a U-Net-based deep learning architecture and a mesh-type 3D modeling technique to fabricate the personalized 3D model. The mean 3D printing time was 258.9 min, and the mean price for production was USD 4.23 for each patient. The size, location, and anatomical relationship of the tumor and thyroid gland could be effectively presented using the mesh-type 3D modeling technique. The group provided with personalized 3D-printed models showed significant improvement in all four categories (general knowledge, benefits and risks of surgery, and satisfaction; all p < 0.05). All patients received a personalized 3D model after surgery and found it helpful to understand the disease, operation, and possible complications and their overall satisfaction (all p < 0.05). In conclusion, the personalized 3D-printed thyroid model may be an effective tool for improving a patient’s understanding and satisfaction during the informed consent process.

Differences in Clinicopathological Characteristics of Papillary Thyroid Carcinoma between Symptomatic and Asymptomatic Patients with Primary Hyperparathyroidism

Background. Popularization of cervical ultrasound led to higher detection of papillary thyroid carcinoma (PTC) and primary hyperparathyroidism (PHPT), as well as increasing percentage of asymptomatic PHPT in China. Although the coexistence of PTC and PHPT has been reported, it is unknown whether the clinicopathological features of PTC differ between asymptomatic and symptomatic PHPT patients. Methods. We retrospectively reviewed the medical records of 304 PHPT patients treated in our hospital between January 2009 and July 2020, including 217 females and 87 males with the average age of 53.27 ± 13.54 years. Of the 304 patients, 181 were symptomatic PHPT patients and 123 were asymptomatic PHPT patients. We analyzed the laboratory results, postoperative pathology, and the TNM stage of PTC between asymptomatic and symptomatic PHPT patients. Results. Concurrent thyroid nodules were found in 61.51% of PHPT patients, and the prevalence of PTC in thyroidectomized PHPT patients was 29.89% in our cohort. Lower serum parathyroid hormone (PTH) ( p < 0.05 ) and calcium ( p < 0.05 ) were found in PHPT patients with PTC compared to patients with benign thyroid lesion. Compared with the symptomatic PHPT patients, the asymptomatic PHPT patients showed lower serum calcium ( p < 0.05 ), serum chlorine ( p < 0.05 ), alkaline phosphatase ( p < 0.05 ), PTH ( p < 0.05 ), and bone turnover markers ( p < 0.05 ) but higher prevalence of thyroid nodules (70.73% versus 55.24%, p < 0.05 ) and PTC (15.44% versus 3.87%, p < 0.05 ). All the PTC in symptomatic PHPT patients were papillary microcarcinoma limited to the thyroid, while 68.42% and 15.78% of the PTC in asymptomatic PHPT patients showed microscopic extrathyroidal extension and lymph node metastases, respectively. Moreover, 36.84% (7/19) of the PTC patients in asymptomatic group showed multifocality, which was much higher than 14.29% (1/7) in the symptomatic group; however, no statistical significance was found ( p = 0.24 ). Conclusions. The concomitant PTC in asymptomatic PHPT patients showed a higher rate of microscopic extrathyroidal invasion when compared to symptomatic PHPT patients. So the FNA is essential to the asymptomatic PHPT patients with suspicious thyroid nodules and once the PTC is confirmed, concurrent parathyroidectomy should be performed with thyroidectomy in asymptomatic PHPT patients.

Spontaneous Thyroid Hemorrhage Caused by Langerhans Cell Histiocytosis: A Case Report and Literature Review

PurposeLangerhans cell histiocytosis (LCH) is a rare clonal disorder of Langerhans antigen-presenting cells. However, thyroid LCH involvement is relatively rare. We present the first case of spontaneous thyroid hemorrhage due to LCH progression and discuss the clinical features, diagnosis, and treatments of thyroid LCH in a literature review.MethodsClinical data were collected. Previously published articles on thyroid LCH involvement were reviewed to assess the clinical features, diagnosis, and treatments for thyroid LCH.ResultsA 54-year-old female presented with a multi-system LCH, affecting the uterus, liver, pituitary gland, and thyroid gland. Clinical stability was achieved after systemic chemotherapy. After 7 years of regular follow up, the patient complained of a sudden painful neck swelling and progressive dyspnea. Computed Tomography revealed bilateral goiter with hematoma, and the patient was diagnosed with spontaneous thyroid bleeding based on her clinical symptoms and radiological findings. The patient was incubated to relieve airway compromise and partial thyroidectomy was performed for definitive treatment. Pathological evaluation further confirmed the diagnosis of thyroid LCH. The patient recovered well after surgery.ConclusionSpontaneous thyroid bleeding due to thyroid LCH progression is extremely rare. Treatments for LCH vary depending on the severity of the disease. We suggest that, for patients with multi-system LCH with thyroid lesion, long-term active surveillance of thyroid hormone concentrations, and thyroid gland volume is required. Physicians should be alert of the potentially life-threatening spontaneous thyroid hemorrhage when aggravated diffuse goiter and hypothyroidism appear. Further investigation is required to establish the guidelines for thyroid LCH treatment.

A Rapidly Enlarging Thyroid Nodule- Aspergillus Abscess

Introduction: Acute suppurative thyroiditis is a rare thyroid disorder with high mortality often due to bacterial or fungal infection. Here we present a case of a rapidly enlarging thyroid nodule in the setting of disseminated aspergillosis. Case: A 31 year old female with lupus on immunosuppressants first presented with weakness to the emergency department with workup finding multiple pulmonary, intracranial and vertebral lesions and a left thyroid nodule. On thyroid ultrasound the nodule was solid, hypoechoic, 1.5x2.3x2.7cm with irregular margins and no echogenic foci. Thyroid function tests: Total T3 52ng/dL (80-210ng/dL), Free T4 2.26ng/dL (0.6-1.12ng/dL), TSH 0.015µIU/mL (0.45-4.12µIU/mL). The patient was started on voriconazole for disseminated aspergillosis with plan for outpatient thyroid workup. However with further brain lesion growth, the patient was readmitted with incidental finding of thyroid nodule developing into a multiloculated, septated, fluid filled 5x2.9x4cm lesion after 3 months. Fine needle aspiration of the thyroid lesion resulted in negative bacterial and fungal cultures, no malignant cells, positive fungal elements consistent with aspergillus on cytology. The patient was continued on antifungal therapy (switched to cresemba due to voriconazole side effects) with thyroid lesion regression to 2.4x0.6x1.3cm at 6 months and 1.8x1.1x1.6cm at 12 months. Her thyroid function test normalized ~ 1 month after initial set of labs and the patient remained clinically euthyroid throughout her course. Discussion: Thyroid infections are limited due to the thyroid’s high iodine content, capsular encasement and rich vascularity. Acute suppurative thyroiditis (AST) due to aspergillus is a rare finding that can present solo or as a part of disseminated infection especially in immunocompromised individuals. Early presentation is often asymptomatic with possible thyroid function test abnormalities that self resolve in a couple weeks. Occasionally patients present with obstructive symptoms or findings of thyroid storm. Diagnosis is done through fine needle aspiration or autopsy, with treatment options including surgery, antifungals or both. Due to the high mortality of fungal AST, with improved outcomes with early diagnosis, it is important to consider AST as a part of the differential diagnosis in immunocompromised patients with systemic illness.