18F-FDG PET/CT concurrent with first radioiodine post-therapeutic scan in high risk differentiated thyroid cancer: a useful tool or just an expensive diversion?

BACKGROUND: Aim of the present study was to evaluate the clinical impact of fluorine-18F-fluorodeoxyglucose PET/CT (18F-FDG-PET/CT) concurrent with post-therapeutic whole-body radioiodine scan (TxWBS) after first radioiodine (RAI) treatment in patients with high-risk differentiated thyroid carcinoma (DTC). METHODS: This was a retrospective, single-center study including 39 patients with DTC (22 females, 17 males, median age 54; IQR: 35-60 years, 87% papillary thyroid cancer, 13% follicular thyroid cancer). All patients underwent 18F-FDG-PET/CT and RAI treatment, both performed off L-T4 about 3 months after total thyroidectomy. TxWBS was obtained 3 days afterwards using planar technique and SPECT/CT of neck and thorax regions. Semiquantitative analysis was performed on positive 18F-FDG-PET/CT scans to assess SUVmax, SUVratio, MTV and TLG values in target lesions (hottest 18F-FDG-positive lesion present in each patient). Receiver operating characteristics (ROC) curve analysis was obtained to establish a cut-off point for SUVmax able to predict the presence of RAI nonavid lesions. Univariate and multivariate analyses were executed to find out predictive factors for abnormal 18F-FDG-PET/CT imaging. RESULTS: In 11 (28%) patients 18F-FDG-PET/CT and TxWBS were both negative and in 9 (23%) both positive, showing loco-regional or distant metastases. In 14 patients (36%) 18F-FDG-PET/CT showed more lesions than TxWBS, while in 5 (13%) patients more lesions were present at TxWBS than 18F-FDG-PET/CT. Overall, 23 patients (59%) showed 18F-FDG avid lesions and 18F-FDG-PET/TC changed the management in 14 (36%), including the choice to perform RAI therapy with higher activities than expected, lymph-node dissection for loco-regional metastases, direct therapy for solitary bone metastases. Through ROC curve analysis, a value superior to 7.25 of SUVmax was able to predict the presence of RAI non-avid lesion at TxWBS. Serum stimulated thyroglobulin and extranodal invasion resulted to be risk factors for abnormal 18F-FDG-PET/CT imaging. However, only extranodal invasion turned out to be an independent risk factor for abnormal 18F-FDG-PET/CT. CONCLUSIONS: The present study demonstrated the clinical value of RAI-concurrent 18F-FDG-PET/CT in patients with high-risk DTC. However, some questions remain open, including the pretherapeutic thyroglobulin level to use as indication to 18F-FDG-PET/CT and the predictive value of 18F-FDG-PET/CT semiquantitative parameters.

Predictors of Malignancy in Children with Thyroid Nodules.

OBJECTIVE: To evaluate the diagnostic accuracy of clinical, laboratory, and ultrasound (US) imaging characteristics of thyroid nodules in assessing the likelihood of malignancy. STUDY DESIGN: Data from 184 children and adolescents with thyroid nodules were evaluated and compared with respective cytologic/histologic outcomes. A regression model was designed to assess the predictors associated with malignancy and to calculate ORs. RESULTS: Twenty-nine malignant neoplasms (25 papillary, 1 medullary, 3 Hurtle-cell carcinomas), 8 follicular adenomas, and 147 goitrous nodules (92 based on cytology, 55 on follow-up) were diagnosed. Fine-needle aspiration biopsy diagnostic accuracy, sensitivity, and specificity were 91%, 100%, and 88%, respectively. Male sex, compression symptoms, palpable lymphopathy, thyroid stimulating hormone concentration, microcalcifications, indistinct margins, hypoechoic US pattern, pathologic lymph node alterations, and increased intranodular vascularization were associated with malignancy. Regular margins, mixed echoic pattern, and peripheral-only vascularization were associated with benignity. During follow-up, nodule growth was associated with malignant disease, especially with levothyroxine therapy. A multivariate analysis confirmed that microcalcifications, hypoechoic pattern, intranodular vascularization, lymph node alterations, and thyroid stimulating hormone concentration were independent predictors of malignant outcome. For each predictor, we provide sensitivity, specificity, and positive/negative predictive values. CONCLUSIONS: Clinical, laboratory, and US features of nodules can be used as predictors of malignancy in children. Although none has diagnostic accuracy as high as that of fine-needle aspiration biopsy, these predictors should be considered in deciding the diagnostic approach of children with thyroid nodules.

Segmental tracheal resection for invasive differentiated thyroid carcinoma. Our experience in eight cases.

PURPOSE: In differentiated thyroid carcinoma (DTC), complete resection of local disease provides the longest survival and the best palliation. In pursuit of this goal, segmental tracheal or laryngotracheal resection can be performed on patients with DTC invading the airway. The study summarizes the technical aspects of the intervention and analyzes its results in eight patients. METHODS: The results of eight tracheal or laryngotracheal resections for DTC invading the airway were analyzed. Three patients presented with local recurrent disease, whereas five underwent airway resection at the time of thyroidectomy or shortly after. All received a circumferential sleeve resection of the trachea (2­4 tracheal rings) that in three cases extended to the cricoid, followed by end-to-end anastomosis. RESULTS: Pathologic evaluation identified seven papillary and one poorly differentiated carcinomas. No postoperative deaths occurred; one patient required surgical reexploration because of postoperative bleeding, and two air leaks resolved with conservative treatment. Functional results were excellent. During follow-up, one patient died of lung and bone metastases, while in two cases locally persistent/recurrent disease has been detected; two patients are currently free of disease, and in the last three cases only persistent thyroglobulin levels are indicative of residual disease. CONCLUSIONS: In our experience, segmental airway resection is safe, provides excellent functional results, and can warrant adequate control of local disease.

18F-fluorocholine PET/CT semi-quantitative analysis in patients affected by primary hyperparathyroidism: a comparison between laboratory and functional data.

INTRODUCTION: This retrospective study aims to establish 18F-fluorocholine (FCH) positron emission tomography/computed tomography (PET/CT) performance in finding hyperfunctioning parathyroid glands, analyze a potential role for semi-quantitative PET parameters and assess factors that may influence PET/CT outcome. METHODS: Forty patients with suspect primary hyperparathyroidism (pHPT) and negative/equivocal conventional imaging underwent FCH-PET/CT in our Institution. For every lesion, visual and semi-quantitative analyses were performed on PET/CT images. In qualitative analysis, a lesion was considered positive if a clear focus of uptake, significantly higher than normal thyroid tissue, was identifiable. Ectopic focal uptake was also regarded as positive PET result. Lesion SUVMax was measured by assigning a spheric VOI to the suspect area of uptake. Thyroid SUVMean was assessed by placing a spheric VOI inside the contralateral thyroid lobe, and SUVratio was calculated using this background region. All patients were subsequently submitted to surgery and histopathologic workup. Sensitivity, positive predictive value (PPV) and accuracy were calculated based on histopathologic reports for every lesion. Pearson's test was used to assess a correlation between laboratory and histopathologic features with SUVr. RESULTS: Four out of the 40 patients who underwent surgery for pHPT had more than one histologic proven unhealthy parathyroid and three had papillary thyroid cancer (PTC). A total of 48 lesions were analyzed. We found 42/48 lesions (87.5%) to have true-positive uptake, whereas three lesions (6.7%) had false-positive uptake (PTC). Three histologic proven parathyroid adenomas showed no uptake (6.7%); the sensitivity/PPV were 93.3% and accuracy was 87,8%. Pearson's test showed a significant correlation between PTH values and parathyroid size with SUVr values (r = 0.56 and 0.55, respectively, p < 0.01 for both features). DISCUSSION: As stated in recent literature, we observed excellent diagnostic sensitivity of FCH-PET/CT in patients with pHPT, providing surgeons a fine tool to optimize treatment. More studies are needed to improve the evaluability of semi-quantitative parameters towards a further improvement of diagnostic accuracy.

Clinical features of thyroid cancer in paediatric age. Experience of a tertiary centre in the 2000-2020 period.

PURPOSE: To describe the clinical features of a paediatric cohort affected by differentiated thyroid cancer (DTC) followed in a tertiary Department of Paediatric Endocrinology. METHODS: Clinical data of 41 patients affected by DTC in the 2000-2020 period were reviewed. RESULTS: The main risk factor was autoimmune thyroiditis (39%). Cytological categories were TIR3b in 39%, TIR4 in 9.8%, TIR5 in 51.2%. After total thyroidectomy, radioiodine treatment was performed in 38 subjects (92.7%). ATA low-risk category was assigned in 11 (30.5%), intermediate-risk category in 15 (41.7%), and high-risk category in 10 patients (27.8%). Age at diagnosis was 15.1 ± 0.92 years in low-risk category, 14.7 ± 0.59 in intermediate-risk category, 11.7 ± 0.89 years in high-risk category (p = 0.01). TIR3b was manly observed in low-risk class (63.6%), while TIR5 was mainly reported in intermediate and high-risk class (60 and 80% respectively) (p = 0.04). Post-surgery stimulated thyroglobulin was increased in high-risk class (407.8 ± 307.1 ng/ml) [p = 0.04]. Tumour size was larger in high-risk category (42.6 ± 2.6 mm), than in low and intermediate-risk categories (19.4 ± 3.5 mm and 28.5 ± 3.9 mm, respectively) (p = 0.008). Patients in intermediate and high-risk categories displayed more tumour multifocality (60 and 90% respectively) (p < 0.005). Disease relapse was mainly observed in high risk category (40%, p = 0.04). CONCLUSION: DTC in childhood is more aggressive than in adults, but the overall survival rate is excellent. The therapeutic approach is still heterogeneous, especially in low-risk category. Further studies are needed to standardise management and reduce disease persistence in childhood.

Parathyroid Retrospective Analysis of Neoplasms Incidence (pTRANI Study): An Italian Multicenter Study on Parathyroid Carcinoma and Atypical Parathyroid Tumour.

BACKGROUND: Parathyroid cancer (PC) is a rare sporadic or hereditary malignancy whose histologic features were redefined with the 2022 WHO classification. A total of 24 Italian institutions designed this multicenter study to specify PC incidence, describe its clinical, functional, and imaging characteristics and improve its differentiation from the atypical parathyroid tumour (APT). METHODS: All relevant information was collected about PC and APT patients treated between 2009 and 2021. RESULTS: Among 8361 parathyroidectomies, 351 patients (mean age 59.0 ± 14.5; F = 210, 59.8%) were divided into the APT (n = 226, 2.8%) and PC group (n = 125, 1.5%). PC showed significantly higher rates (p < 0.05) of bone involvement, abdominal, and neurological symptoms than APT (48.8% vs. 35.0%, 17.6% vs. 7.1%, 13.6% vs. 5.3%, respectively). Ultrasound (US) diameter >3 cm (30.9% vs. 19.3%, p = 0.049) was significantly more common in the PC. A significantly higher frequency of local recurrences was observed in the PC (8.0% vs. 2.7%, p = 0.022). Mortality due to consequences of cancer or uncontrolled hyperparathyroidism was 3.3%. CONCLUSIONS: Symptomatic hyperparathyroidism, high PTH and albumin-corrected serum calcium values, and a US diameter >3 cm may be considered features differentiating PC from APT. 2022 WHO criteria did not impact the diagnosis.

The THYCOVIT (Thyroid Surgery during COVID-19 pandemic in Italy) study: results from a nationwide, multicentric, case-controlled study.

The outbreak of the COVID-19 pandemic has led to a disruption of surgical care. The aim of this multi-centric, retrospective study was to evaluate the impact of the pandemic on surgical activity for thyroid disease among the Italian Units of Endocrine Surgery. Three phases of the pandemic were identified based on the epidemiological situation and the public measures adopted from the Italian Government (1st phase: from 9th March to 3rd May 2020; 2nd phase: from 4th May to 14th June; 3rd phase: from 15th June to 31st). The patients operated upon during these phases were compared to those who underwent surgery during the same period of the previous year. Overall, 3892 patients from 28 Italian endocrine surgical units were included in the study, 1478 (38%) operated upon during COVID-19 pandemic, and 2414 (62%) during the corresponding period of 2019. The decrease in the number of operations was by 64.8%, 44.7% and 5.1% during the three phases of COVID-19 pandemic, compared to 2019, respectively. During the first and the second phases, the surgical activity was dedicated mainly to oncological patients. No differences in post-operative complications were noted between the two periods. Oncological activity for thyroid cancer was adequately maintained during the COVID-19 pandemic.

Parathyroid Carcinoma: An Up-to-Date Retrospective Multicentric Analysis.

Parathyroid carcinoma (PC) is a rare disease responsible for about 1% of primary hyperparathyroidism (PHPT) cases. PC usually has an indolent course, tough to differentiate from the benign causes of PHPT, and the only certain diagnosis is histologic. The gold standard surgical treatment is the en bloc resection associated with the homolateral thyroid loboistmectomy. The aim of this study was to underline the main differences between PC and benign PHPT, along with gathering epidemiological knowledge relative to PC in our region. Data from the regional cancer network (Rete Oncologica del Piemonte e della Valle d'Aosta) since 2007 have been reported, including 21 patients from three hospitals (AO S. Croce e Carle of Cuneo, AOU Città della Salute of Turin, and ASL Città di Torino). The incidence of the disease, gender, age at time of diagnosis, presence of renal and bone symptoms, serum calcium and PTH levels, surgical technique performed, and percentage of recurrence were analysed. PC data were than compared with a series of patients affected by benign PHPT, referred to ASL Città di Torino, Maria Vittoria Hospital, from 2007 to 2019. A PC incidence of 0.05 cases per 100,000 inhabitants was found in our region. Benign forms occurred more frequently in females (p=0.0002), while PC equally occurred in males and females and affected younger patients (p=0.026). Serum calcium and PTH levels were significantly higher in PC patients; accordingly, typical PHPT symptoms were more frequently reported in PC than in benign PHPT. In the PC group, the en bloc resection shows a 13 times lower risk for relapse compared with all the other surgical techniques. PC is equally gender distributed, and the average patients' age is in the fifth decade of life. It is usually functioning, with greater biochemical activity and multiple symptoms. A not-radical surgical resection is associated with a higher recurrence rate. A meticulous presurgical evaluation of PHPT patients showing PC's evocative features is mandatory to obtain a complete disease extirpation.

Merits of the PMiT (papillary microtumor) terminology in the definition of a subset of incidental papillary microcarcinomas of the thyroid.

An exponential increase in the detection of papillary thyroid microcarcinomas (PTMCs) has been observed in recent times, possibly because of recent improvements in the management of thyroid lesions and extensive histological examination. However, no definitive treatment guideline has been developed for PTMC, resulting in patients undergoing overtreatment. In 2003, the term papillary microtumor of the thyroid (PMiT) was proposed for small (< or =1 cm) intrathyroidal tumors with excellent prognostic prospects along with strict definition criteria. Since then, the term PMiT has been adopted by clinicians and surgeons. In this article, the authors report a series of 50 consecutive cases of PMiT collected and treated at the University Hospital of Turin, Italy. From the authors' experience, this terminology, which demarks a subset of PTMC, should be widely adopted as it is biologically sound, well accepted by both clinicians and patients, decreases the danger of overtreatment, minimizes the psychological anxiety engendered by a diagnosis of carcinoma, and maintains the patient's eligibility for health insurance.

Galectin-3-expression analysis in the surgical selection of follicular thyroid nodules with indeterminate fine-needle aspiration cytology: a prospective multicentre study.

BACKGROUND: In the USA, about 30 200 well-differentiated thyroid carcinomas were diagnosed in 2007, but the prevalence of thyroid nodules is much higher (about 5% of the adult population). Unfortunately, the preoperative characterisation of follicular thyroid nodules is still a challenge, and many benign lesions, which remain indeterminate after fine-needle aspiration (FNA) cytology are referred to surgery. About 85% of these thyroid nodules are classified as benign at final histology. We aimed to assess the diagnostic effect of galectin-3 expression analysis in distinguishing preoperatively benign from malignant follicular thyroid nodules when FNA findings were indeterminate. METHODS: 544 patients were enrolled between June 1, 2003, and Aug 30, 2006. We used a purified monoclonal antibody to galectin-3, a biotin-free immunocytohistochemical assay, and a morphological and phenotypic analysis of FNA-derived cell-block preparations. Galectin-3-expression analysis was applied preoperatively on 465 follicular thyroid proliferations that were candidates for surgery, and its diagnostic accuracy was compared with the final histology. FINDINGS: 31 patients were excluded because they had small galectin-3-negative thyroid nodules; we did not have data for 47 patients; and one patient with an oncocytic nodule was excluded. 331 (71%) of the assessable 465 preoperative thyroid FNA samples did not express galectin-3. 280 (85%) of these galectin-3-negative lesions were classified as benign at final histology. Galectin-3 expression was detected, instead, in 134 of 465 (29%) thyroid proliferations, 101 (75%) of which were confirmed as malignant. The overall sensitivity of the galectin-3 test was 78% (95% CI 74-82) and specificity was 93% (90-95). Estimated positive predictive value was 82% (79-86) and negative predictive value was 91% (88-93). 381 (88%) of 432 patients with follicular thyroid nodules who were referred for thyroidectomy were correctly classified preoperatively by use of the galectin-3 test. However, 29 (22%) of 130 cancers were missed by the galectin-3 method. INTERPRETATION: Our findings show that if the option of surgery was based theoretically on galectin-3 expression alone, only 134 thyroid operations would have been done in 465 patients; therefore a large proportion (71%) of unnecessary thyroid surgical procedures could be avoided, although a number of galectin-3-negative cancers could be potentially missed. The galectin-3 test proposed here does not replace conventional FNA cytology, but represents a complementary diagnostic method for those follicular nodules that remain indeterminate.

Ultrasound screening for thyroid carcinoma in childhood cancer survivors: a case series.

CONTEXT: Childhood cancer survivors need regular monitoring into young adulthood and beyond, because they are at risk for developing late-onset complications of cancer therapy, including second malignancies. OBJECTIVE: This study focuses on the use of thyroid ultrasound to screen for thyroid carcinoma in a population of childhood cancer survivors. PATIENTS: A total of 129 subjects who had received radiotherapy to the head, neck, or upper thorax for a pediatric cancer were studied in the setting of a long-term follow-up unit. DESIGN: Thyroid ultrasound usually began 5 yr after radiotherapy and was repeated every third year, if negative. Median follow-up time since childhood cancer diagnosis was 15.8 yr (range 6.1-34.8 yr). Solid thyroid nodules were found in 35 patients. Fine-needle aspiration was performed in 19 patients, of which 14 had nodules above 1 cm. MAIN OUTCOME MEASURE: The main outcome measure was the finding of not palpable thyroid cancers. RESULTS: Cytological examination of specimens diagnosed papillary carcinoma in five patients who underwent surgery. The cytological diagnosis of papillary thyroid carcinoma was confirmed in all cases by histological examination. Notably, only two of these patients had palpable nodules; the other three were smaller than 1 cm and were detected only by ultrasound. However, histological examination showed nodal metastases in two of these. CONCLUSIONS: Although ultrasound screening for thyroid cancer in the general population is not cost effective and could lead to unnecessary surgery, due to false positives, we believe that in childhood cancer survivors who received radiotherapy involving the head, neck, or upper thorax, it would be worthwhile.

Anaplastic thyroid carcinoma: clinical outcome of 30 consecutive patients referred to a single institution in the past 5 years.

OBJECTIVE: Treatment options for anaplastic thyroid carcinoma (ATC), which is one of the most lethal human malignant tumors, include surgery, chemotherapy and radiotherapy usually combined in a multimodal approach, to improve survival and avoid death from local invasion. However, there is no standard protocol for ATC treatment and the optimal sequence within multimodal therapy is debated. We retrospectively report the clinical outcome of 30 ATC patients referred consecutively to the Oncological Endocrinology Unit of San Giovanni Battista Hospital (Turin, Italy) between 2000 and 2005. DESIGN: Patients were treated by one of the following approaches: i) surgery followed by adjuvant-combined chemoradiotherapy; ii) neo-adjuvant chemoradiotherapy followed by surgery and adjuvant chemotherapy; or iii) chemotherapy alone. The surgical procedures were classified as 'maximal debulking' or 'palliative resection'. Maximal debulking entailed total or near-total thyroidectomy and complete resection of all gross tumor or minimal residual disease adherent to vital structures, independently of the presence or absence of distant metastases. In palliative resections, macroscopic residual disease was left in the neck. Survival of patients stratified by treatment was assessed. RESULTS: Analysis of multivariate hazard ratios showed that maximal debulking followed by adjuvant chemoradiotherapy was the only treatment that modified survival of ATC patients (hazard ratio= 0.23, 95% CI: 0.07-0.79), even if factors determining poor prognosis or increased surgical risk were present. CONCLUSIONS: Despite the overall grim outcome of ATC, these results justify an attempt at maximal debulking surgery, followed by adjuvant chemoradiotherapy, possibly in all ATC patients.

Thyroidectomy for Graves' hyperthyroidism. Retrospective study of patients' appreciation.

AIM OF THE STUDY: To retrospectively investigate the patients' views of surgical treatment of Graves' hyperthyroidism. METHODS: One hundred two patients were included in the study and submitted to extensive subtotal thyroidectomy or total thyroidectomy between 1993-2003. Data were acquired from the responses to a questionnaire, that was completed by 83 patients. RESULTS: Before the operation the working/studying ability and the social/emotional relations were impaired in 20% and 22% of cases. Preoperative information was adequate for 84% of patients. The perception of the hospital efficiency was favourable in 89% of cases, and the interpersonal relations with clinicians and nurses were very positive for 96% of patients. After the operation, all patients were hypothyroid on levothyroxine (l-T4); unexpected problems with l-T4 therapy occurred in 6% of cases. Voice changes or neck discomfort were reported by 29% and 8% of patients. The aesthetic appearance of the scar was very satisfactory for 70% of patients, but 11% were unsatisfied. The working/studying ability and the social/emotional relations improved in 63% and 59% of cases. Eye symptoms improved in 71% of the patients with endocrine ophthalmopathy, but got worse in 60%. The quality of life, expressed with a 0 to 10 scale, improved from a mean preoperative score of 4.7 to a mean score of 7.9 (P = 0.000). Only 5% of patients expressed hesitation to recommend surgery to a friend with similar disease. CONCLUSIONS: Surgery is an effective therapy for selected cases of Graves' disease and meets the expectations of the majority of patients. Nevertheless some possible factors for dissatisfaction are pointed out.

Tracheobronchopathia osteochondroplastica in recurrent retrosternal goiter. Surgical management.

Tracheobronchopathia osteochondroplastica (TPO) is a rare pathology characterized by a progressive segmentary stenosis of the respiratory tract due to proliferation of osteocartilagineous nodules in the lumen of the distal part of the trachea and large bronchial trunks. Prognosis is usually benign, but some cases with an acute progression and a lethal outcome have been described. Clinical presentation is non specific, the chest x-ray is generally normal and there are not typical radiological signs of suspicion: diagnosis of TPO is usually incidental. We report a case of TPO associated with a retrosternal recurrent goiter. The CT scan conducted to evaluate the extension and the vascular relationships showed the characteristic lesions of the TPO with a segmental stenosis of the trachea greater than 70%. A bronchofiberoscopy confirmed the suspect of TPO. To date, the clinical studies carried out do not show a certain etiology, but all agree that chronic damage or chronic inflammations could be the cause of the onset of structural anomalies of the respiratory tract In literature, there is only a report which describes an association between TPO and thyroid pathology. It is obscure whatever these disease could be etiologically or fortuitously associated but a relationship cannot be completely excluded. Surgeons, anesthetists and radiologists which deal with thyroid pathology must recognize the disease, especially in the presence of bulky retrosternal goiters, to make a correct diagnosis and provide adequate perioperative management. KEY WORDS: Mediastinal goiter, Osteocartilagineous Nodules, Tracheal Stenosis, Total Thyroidectomy, Tracheobronchopathia Osteochondroplastica.

Ultrasound surveillance for radiation-induced thyroid carcinoma in adult survivors of childhood cancer.

INTRODUCTION: The optimal surveillance strategy to screen for thyroid carcinoma childhood cancer survivors (CCS) at increased risk is still debated. In our clinical practice, beside neck palpation we routinely perform thyroid ultrasound (US). Here we describe the results obtained using this approach. METHODS: We considered all CCS referred to our long term clinic from November 2001 to September 2014. One hundred and ninety-seven patients who had received radiation therapy involving the thyroid gland underwent US surveillance. Thyroid US started 5 years after radiotherapy and repeated every 3 years, if negative. RESULTS: Among 197 CCS previously irradiated to the thyroid gland, 74 patients (37.5%) developed thyroid nodules, and fine-needle aspiration was performed in 35. In 11 patients the cytological examination was suspicious or diagnostic for malignancy (TIR 4/5), whereas a follicular lesion was diagnosed in nine. Patients with TIR 4/5 cytology were operated and in all cases thyroid cancer diagnosis was confirmed. The nine patients with TIR 3 cytology also underwent surgery and a carcinoma was diagnosed in three of them. Prevalence of thyroid cancer was 7.1%. Tumour size ranged between 4 and 25 mm, but six (43%) were classified T3 because of extra-thyroidal extension. Six patients had nodal metastases; in eight patients the tumour was multifocal. At the time of the study all patients are disease free, without evidence of surgery complications. CONCLUSION: Applying our US surveillance protocol, the prevalence of radiation-induced thyroid cancer is high. Histological features of the thyroid cancers diagnosed in our cohort suggest that most of them were clinically relevant tumours.

Clinical challenges with calcitonin-negative medullary thyroid carcinoma.

PURPOSE: Medullary thyroid carcinoma (MTC) is a relatively uncommon malignant tumor of the parafollicular C cells of the thyroid, which distinguishing feature is the production of calcitonin (CT). CT is a well-recognized tool in the diagnosis and the postsurgical follow-up of patients with MTC with a high sensitivity and specificity, and represents a powerful prognostic indicator. Usually, there is a direct correlation between tumor size and basal CT levels. However, few cases of CT-negative MTCs have been reported in literature and criteria for diagnosis and follow-up are still controversial. METHODS: We performed a brief review on CT-negative MTC and reported our experience on this rare condition, focusing on the clinical characteristics at presentation, the histological and immunostaining features, and the management. RESULTS: Fifteen cases of large, palpable, CT-negative MTCs have been reported in the literature so far; moreover, we reported four cases followed at our center. CONCLUSIONS: Although CT-negative MTC is rare, normal/low serum levels of CT and CEA cannot completely exclude the possibility of the diagnosis, when suspected. It is well accepted that early diagnosis is crucial, but there is still no consensus on the optimal postoperative surveillance strategy. The ultrasound evaluation of the cervical region, together with abdominal computerized tomography scan, chest X-ray, and fluorine18-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography (FDG-PET/CT), would be recommended in the follow-up of such cases.

Thyroidectomy for Painful Thyroiditis Resistant to Steroid Treatment: Three New Cases with Review of the Literature.

Thyroidal pain is usually due to subacute thyroiditis (SAT). In more severe forms prednisone doses up to 40 mg daily for 2-3 weeks are recommended. Recurrences occur rarely and restoration of steroid treatment cures the disease. Rarely, patients with Hashimoto's thyroiditis (HT) have thyroidal pain (painful HT, PHT). Differently from SAT, occasional PHT patients showed no benefit from medical treatment so that thyroidectomy was necessary. We report three patients who did not show clinical response to prolonged high dose prednisone treatment: a 50-year-old man, a 35-year-old woman, and a 33-year-old woman. Thyroidectomy was necessary, respectively, after nine-month treatment with 50 mg daily, two-month treatment with 75 mg daily, and one-month treatment with 50 mg daily. The two women were typical cases of PHT. Conversely, in the first patient, thyroid histology showed features of granulomatous thyroiditis, typical of SAT, without fibrosis or lymphocytic infiltration, typical of HT/PHT, coupled to undetectable serum anti-thyroid antibodies. Our data (1) suggest that not only PHT but also SAT may show resistance to steroid treatment and (2) confirm a previous observation in a single PHT patient that increasing prednisone doses above conventional maximal dosages may not be useful in these patients.

Diagnostic performance of elastography in cytologically indeterminate thyroid nodules.

Cytological examination of material from fine-needle aspiration biopsy is the mainstay of diagnosis of thyroid nodules, thanks to its remarkable accuracy and scarcity of complications. However, follicular lesions (also called indeterminate lesions or Thy3 in the current classification), a heterogeneous group of lesions in which cytology is unable to give a definitive diagnosis to, represent its main limit. Elastography has been proposed as a potential diagnostic tool to define the risk of malignancy in the aforementioned nodules, but at present there is no conclusive data due to the small number of specifically addressed studies and the lack of concordance among them. The objective of our study was to evaluate the role of real-time elastography (RTE) for refining diagnosis of Thy3 nodules, by integrating diagnostic information provided by traditional ultrasound (US). The study included 108 patients with Thy3 nodules awaiting for surgery, which were evaluated by US (considering hypoecogenicity, irregular margins, microcalcifications, halo sign, and intranodular vascularization) and RTE. Nodules were classified at RTE using a four-class color scale. At histologic examination, 75 nodules were benign and 33 malignant. As expected, none of the ultrasound parameters alone was adequate in predicting malignancy or benignity of the nodules; in the presence of at least two US risk factors, we obtained 61 % sensitivity, 83 % specificity, and 77 % accuracy with 6.8 OR (95 % CI 2.4-20.4). RTE scores 3 and 4 showed 76 % sensitivity, 88 % specificity, 74 % PPV, and 89 % NPV with diagnostic accuracy of 84 %; the data are statistically significant (p < 0.0001) with a OR of 21.9 (95 % CI 7.1-76). By combining RTE with US parameters, the presence of at least 2 characters of suspicion had 88 % sensitivity and 94 % NPV with 23.8 OR (95 % CI 7-106.3). The use of combined RTE and US leads to the identification of two patients subpopulations which have a significantly different malignancy risk (6 vs. 63 %); further studies are needed to verify if it is possible to send only the first group to thyroidectomy and the other to follow-up.

Utilility of flow cytometry as ancillary study to improve the cytologic diagnosis of thyroid lymphomas.

BACKGROUND: To evaluate the efficacy of the use of flow cytometry (FC) immunophenotyping together with fine-needle aspiration cytology (FNAC) in the diagnosis of thyroid lymphoma. METHODS: FC was performed in parallel with FNAC in 35 samples of suspected thyroid lymphoma over a 12 years period. Results were correlated with histological or molecular findings and follow-up, when available. RESULTS: A final diagnosis of lymphoma was given in 13 of 35 (37.1%) specimens. Among the 22 cases considered negative for lymphoma by FC, 11 were diagnosed as thyroiditis by cytology, 7 as reactive, 2 were anaplastic carcinoma, and 2 cases were considered cytologically suspicious for lymphoma but were not confirmed by further investigations. Histology on core biopsy or molecular analysis was available in 12 of 13 lymphoma cases (92.3%). Data obtained by the combination cytology/FC were confirmed in all cases on histology biopsies. Correlation with histology showed a sensitivity and a specificity of 100% for the combination cytology/FC. CONCLUSIONS: FC is an important additional test that can contribute with cytology to the identification of lymphomas of the thyroid. FC can detect the presence of small neoplastic lymphocyte populations and may contribute to the diagnosis of cases in which the lymphoid infiltrate is difficult to interpret on cytology alone.