Livia Lamartina

The natural history of benign thyroid nodules

IMPORTANCE Detection of asymptomatic thyroid nodules has increased. Consensus is lacking regarding the optimal follow-up of cytologically proven benign lesions and sonographically nonsuspicious nodules. Current guidelines recommend serial ultrasound examinations and reassessment of cytology if significant growth is observed. OBJECTIVE To determine the frequency, magnitude, and factors associated with changes in thyroid nodule size. DESIGN, SETTING, AND PARTICIPANTS Prospective, multicenter, observational study involving 992 consecutive patients with 1 to 4 asymptomatic, sonographically or cytologically benign thyroid nodules. Patients were recruited from 8 hospital-based thyroid-disease referral centers in Italy between 2006 and 2008. Data collected during the first 5 years of follow-up, through January 2013, were analyzed. MAIN OUTCOMES AND MEASURES Baseline nodule growth (primary end point) was assessed with yearly thyroid ultrasound examinations. Size changes were considered significant for growth if an increase of 20% or more was recorded in at least 2 nodule diameters, with a minimum increase of 2 mm. Baseline factors associated with growth were identified. Secondary end points were the sonographic detection of new nodules and the diagnosis of thyroid cancer during follow-up. RESULTS Nodule growth occurred in 153 patients (15.4% [95% CI, 14.3%-16.5%]). One hundred seventy-four of the 1567 original nodules (11.1% [95% CI, 10.3%-11.9%]) increased in size, with a mean 5-year largest diameter increase of 4.9 mm (95% CI, 4.2-5.5 mm), from 13.2 mm (95% CI, 12.1-14.2 mm) to 18.1 mm (95% CI, 16.7-19.4 mm). Nodule growth was associated with presence of multiple nodules (OR, 2.2 [95% CI 1.4-3.4] for 2 nodules; OR, 3.2 [95% CI, 1.8-5.6 for 3 nodules; and OR, 8.9 [95% CI, 4.4-18.0] for 4 nodules), main nodule volumes larger than 0.2 mL (OR, 2.9 [95% CI, 1.7-4.9] for volumes >0.2 to <1 mL and OR, 3.0 [95% CI, 1.8-5.1] for volumes ≥1 mL), and male sex (OR, 1.7 [95% CI, 1.1-2.6]), whereas an age of 60 years or older was associated with a lower risk of growth than age younger than 45 years (OR, 0.5 [95% CI 0.3-0.9]). In 184 individuals (18.5% [95% CI, 16.4%-20.9%]), nodules shrank spontaneously. Thyroid cancer was diagnosed in 5 original nodules (0.3% [95% CI, 0.0%-0.6%]). Only 2 had grown. An incidental cancer was found at thyroidectomy in a nonvisualized nodule. New nodules developed in 93 patients (9.3% [95% CI, 7.5%-11.1%]), with detection of one cancer. CONCLUSIONS AND RELEVANCE Among patients with asymptomatic, sonographically or cytologically benign thyroid nodules, the majority of nodules exhibited no significant size increase during 5 years of follow-up and thyroid cancer was rare. These findings support consideration of revision of current guideline recommendations for follow-up of asymptomatic thyroid nodules.

Identification and optimal postsurgical follow-up of patients with very low-risk papillary thyroid microcarcinomas

CONTEXT Most papillary thyroid microcarcinomas (PTMCs; ≤ 1 cm diameter) are indolent low-risk tumors, but some cases behave more aggressively. Controversies have thus arisen over the optimum postoperative surveillance of PTMC patients. OBJECTIVES We tested the hypothesis that clinical criteria could be used to identify PTMC patients with very low mortality/recurrence risks and attempted to define the best strategy for their management and long-term surveillance. DESIGN We retrospectively analyzed data from 312 consecutively diagnosed PTMC patients with T1N0M0 stage disease, no family history of thyroid cancer, no history of head-neck irradiation, unifocal PTMC, no extracapsular involvement, and classic papillary histotypes. Additional inclusion criteria were complete follow-up data from surgery to at least 5 yr after diagnosis. All 312 had undergone (near) total thyroidectomy [with radioactive iodine (RAI) remnant ablation in 137 (44%) - RAI group] and were followed up yearly with cervical ultrasonography and serum thyroglobulin, TSH, and thyroglobulin antibody assays. RESULTS During follow-up (5-23 yr, median 6.7 yr), there were no deaths due to thyroid cancer or reoperations. The first (6-12 months after surgery) and last postoperative cervical sonograms were negative in all cases. Final serum thyroglobulin levels were undetectable (<1 ng/ml) in all RAI patients and almost all (93%) of non-RAI patients. CONCLUSION Accurate risk stratification can allow safe follow-up of most PTMC patients with a less intensive, more cost-effective protocol. Cervical ultrasonography is the mainstay of this protocol, and negative findings at the first postoperative examination are highly predictive of positive outcomes.

Low-Risk Differentiated Thyroid Cancer and Radioiodine Remnant Ablation: A Systematic Review of the Literature

BACKGROUND Radioiodine remnant ablation (RRA) has traditionally been one of the cornerstones of differentiated thyroid cancer (DTC) treatment. The decision to use RRA in low-risk (LR) and intermediate-risk (IR) patients is controversial. The aim of this review is to examine the evidence of RRA benefit in the staging, follow-up, and recurrence prevention in LR and IR DTC patients. METHODS From a PubMed search, we selected original papers (OPs) using the following inclusion criteria: 1) DTC; 2) LR and IR patients; 3) non-RRA-treated patients or RRA-treated vs non-RRA-treated groups; 4) a report of the outcome of cancer recurrence; and 5) publication since 2008. RESULTS Neck ultrasonography is superior to whole-body scan for disease detection in the neck. A rising or declining serum thyroglobulin level over time provides an excellent positive or negative predictive value, respectively, even in non-RRA-treated patients. No OP demonstrating RRA benefit on recurrence in LR patients was found; two OPs found no evidence of benefit. We found 11 OPs that observed some benefit in reducing recurrence rates with RRA in IR patients and 13 OPs that failed to show benefit from RRA in this group. CONCLUSIONS Neck ultrasonography and serum thyroglobulin measurement are equivalent or superior in detecting and localizing residual disease compared to post-therapy whole-body scan. There is no evidence of RRA benefit in recurrence prevention for LR patients. There are conflicting data on IR patients and only a few studies with homogenous and properly stratified populations. A careful evaluation of tumor pathological features and patient characteristics and preferences should guide RRA decision making.

Ultrasonography scoring systems can rule out malignancy in cytologically indeterminate thyroid nodules

PurposeTo assess the accuracy and reproducibility of ultrasonography classification systems in characterizing cytologically indeterminate thyroid nodules.MethodsWe retrospectively identified 49 nodules that had been surgically resected owing to features classified as indeterminate according to 2010 Italian Consensus on Thyroid Cytology criteria. Three experienced sonographers independently reviewed original sonographic images of each nodule and classified it using the 2015 American Thyroid Association (ATA) guidelines and the Thyroid Imaging Reporting and Data System (TI-RADS) classification proposed by Korean radiologists; later, images were reviewed jointly to obtain consensus classifications of each nodule. Original cytology slides were similarly reviewed by three experienced cytopathologists, who reclassified the nodule (independently, then jointly) according to revised Italian Consensus on Thyroid Cytology (ICTC-2014) criteria. Consensus ICTC-2014, ATA, and TI-RADS classifications were analyzed against surgical histology reports to estimate each system’s sensitivity, specificity, positive and negative predictive values.ResultsOf the 49 indeterminate nodules examined, 30 (61.2 %) were histologically benign. Consensus ICTC-2014 classification correctly classified malignant nodules with positive predictive value of 50 % and negative predictive value of 90 %. Sonographic classification of nodules as intermediate to high suspicion by ATA or TI-RADS category 4c displayed positive predictive value of 63 and 71 %, respectively; positive predictive values dropped to 44 and 42 % when lower positivity thresholds were used (ATA low suspicion, TI-RADS category 4a). Negative predictive values for ATA and TI-RADS were 91 and 74 %, respectively, with higher positivity thresholds and 100 % for both with lower thresholds. All systems displayed appreciable inter-observer variability (Krippendorff alphas: ATA 0.36, TIRADS 0.42, ICTC-2014 0.74).ConclusionsWith stringent negativity cut-offs, American Thyroid Association and Thyroid Imaging Reporting and Data System assessment of cytologically indeterminate thyroid nodules allows high-confidence exclusion of malignancy.

BRAF V600E and risk stratification of thyroid microcarcinoma: a multicenter pathological and clinical study.

Studies from single institutions have analyzed BRAF in papillary microcarcinomas, sometimes with contradictory results. Most of them have provided limited integration of histological and clinical data. To obtain a comprehensive picture of BRAF V600E-mutated microcarcinomas and to evaluate the role of BRAF testing in risk stratification we performed a retrospective multicenter analysis integrating microscopical, pathological, and clinical information. Three hundred and sixty-five samples from 300 patients treated at six medical institutions covering different geographical regions of Italy were analyzed with central review of all cases. BRAF V600E statistical analysis was conducted on 298 microcarcinomas from 264 patients after exclusion of those that did not meet the required criteria. BRAF V600E was identified in 145/298 tumors (49%) including the following subtypes: 35/37 (95%, P<0.0001) tall cell and 72/114 (64%, P<0.0001) classic; conversely 94/129 follicular variant papillary microcarcinomas (73%, P<0.0001) were BRAF wild type. BRAF V600E-mutated microcarcinomas were characterized by markedly infiltrative contours (P<0.0001) with elongated strings of neoplastic cells departing from the tumor, and by intraglandular tumor spread (P<0.0001), typically within 5 mm of the tumor border. Multivariate analysis correlated BRAF V600E with specific microscopic features (nuclear grooves, optically clear nuclei, tall cells within the tumor, and tumor fibrosis), aggressive growth pattern (infiltrative tumor border, extension into extrathyroidal tissues, and intraglandular tumor spread), higher American Thyroid Association recurrence risk group, and non-incidental tumor discovery. The following showed the strongest link to BRAF V600E: tall cell subtype, many neoplastic cells with nuclear grooves or with optically clear nuclei, infiltrative growth, intraglandular tumor spread, and a tumor discovery that was non-incidental. BRAF V600E-mutated microcarcinomas represent a distinct biological subtype. The mutation is associated with conventional clinico-pathological features considered to be adverse prognostic factors for papillary microcarcinoma, for which it could be regarded as a surrogate marker. BRAF analysis may be useful to identify tumors (BRAF wild type) that have negligible clinical risk.

Risk Stratification of Neck Lesions Detected Sonographically During the Follow-Up of Differentiated Thyroid Cancer

CONTEXT The European Thyroid Association (ETA) has classified posttreatment cervical ultrasound findings in thyroid cancer patients based on their association with disease persistence/recurrence. OBJECTIVE The objective of the study was to assess this classifications ability to predict the growth and persistence of such lesions during active posttreatment surveillance of patients with differentiated thyroid cancer (DTC). DESIGN This was a retrospective, observational study. SETTING The study was conducted at a thyroid cancer center in a large Italian teaching hospital. PATIENTS Center referrals (2005-2014) were reviewed and patients selected with pathologically-confirmed DTC; total thyroidectomy, with or without neck dissection and/or radioiodine remnant ablation; abnormal findings on two or more consecutive posttreatment neck sonograms; and subsequent follow-up consisting of active surveillance. Baseline ultrasound abnormalities (thyroid bed masses, lymph nodes) were classified according to the ETA system. Patients were divided into group S (those with one or more lesions classified as suspicious) and group I (indeterminate lesions only). We recorded baseline and follow-up clinical data through June 30, 2015. MAIN OUTCOMES The main outcomes were patients with growth (>3 mm, largest diameter) of one or more lesions during follow-up and patients with one or more persistent lesions at the final visit. RESULTS The cohort included 58 of the 637 DTC cases screened (9%). A total of 113 lesions were followed up (18 thyroid bed masses, 95 lymph nodes). During surveillance (median 3.7 y), group I had significantly lower rates than group S of lesion growth (8% vs 36%, P = .01) and persistence (64% vs 97%, P = .014). The median time to scan normalization was 2.9 years. CONCLUSIONS The ETAs evidence-based classification of sonographically detected neck abnormalities can help identify papillary thyroid cancer patients eligible for more relaxed follow-up.

Antiangiogenic Tyrosine Kinase Inhibitors: Occurrence and Risk Factors of Hemoptysis in Refractory Thyroid Cancer

BACKGROUND Antiangiogenic tyrosine kinase inhibitors (TKIs) are the mainstay of advanced thyroid cancer (TC) treatment. Concern is rising about TKI-related toxicity. OBJECTIVE To determine the incidence and to investigate the risk factors of hemoptysis in TC patients during TKI treatment. METHODS We analyzed consecutive TC patients treated with TKI in our center between 2005 and 2013 and performed an independent review of computed tomography scan images for airway invasion assessment. Occurrence of grade 1-2 or grade 3-5 hemoptysis according to Common Terminology Criteria for Adverse Events version 4.03 and risk factors for hemoptysis were investigated. RESULTS A total of 140 patients (89 males; median age, 52 y) with medullary (56%), differentiated (33%), and poorly differentiated (11%) TC were enrolled. Thyroidectomy±neck dissection was performed in 123 patients and neck/mediastinum external-beam radiotherapy in 41 (32% with therapeutic purpose and 68% with adjuvant purpose). Patients received from 1 to 4 lines of TKI (median 1). Median follow-up was 24 months. Airway invasion was found in 65 (46%) cases. Hemoptysis occurred in 9 patients: grade 1-2 in 7 cases (5%) and grade 3-5 in 2 (1.4%) cases (fatal in 1). Hemoptysis was associated with presence of airway invasion (P = .04), poorly differentiated pathology (P = .03), history of therapeutic external-beam radiotherapy (P = .003), and thyroidectomy without neck dissection (P = .02). CONCLUSION Airway invasion, poorly differentiated pathology, therapeutic external-beam radiotherapy, and thyroidectomy without neck dissection are associated with and increased risk of hemoptysis in TC patients during antiangiogenic TKI treatment. Further research is needed to confirm this data and to sort out interactions between these risk factors. A careful assessment of airway invasion is mandatory before TKI introduction.

Follicular thyroid cancer and Hürthle cell carcinoma: challenges in diagnosis, treatment, and clinical management

Follicular thyroid cancer is the second most common differentiated thyroid cancer histological type and has been overshadowed by its more common counterpart-papillary thyroid cancer-despite its unique biological behaviour and less favourable outcomes. In this Review, we comprehensively review the literature on follicular thyroid cancer to provide an evidence-based guide to the management of these tumours, to highlight the lack of evidence behind guideline recommendations, and to identify changes and challenges over the past decades in diagnosis, prognosis, and treatment. We highlight that correct identification of cancer in indeterminate cytological samples is challenging and ultrasonographic features can be misleading. Despite certain unique aspects of follicular thyroid cancer presentation and prognosis, no specific recommendations exist for follicular thyroid cancer and Hürthle cell carcinoma in evidence-based guidelines. Efforts should be made to stimulate additional research in this field.

ENDOCRINE TUMOURS: Imaging in the follow up of differentiated thyroid cancer: current evidence and future perspectives for a risk-adapted approach

The clinical and epidemiological profiles of differentiated thyroid cancers (DTCs) have changed in the last three decades. Todays DTCs are more likely to be small, localized, asymptomatic papillary forms. Current practice is, though, moving toward more conservative approaches (e.g. lobectomy instead of total thyroidectomy, selective use of radioiodine). This evolution has been paralleled and partly driven by rapid technological advances in the field of diagnostic imaging. The challenge of contemporary DTCs follow-up is to tailor a risk-of-recurrence-based management, taking into account the dynamic nature of these risks, which evolve over time, spontaneously and in response to treatments. This review provides a closer look at the evolving evidence-based views on the use and utility of imaging technology in the post-treatment staging and the short- and long-term surveillance of patients with DTCs. The studies considered range from cervical US with Doppler flow analysis to an expanding palette of increasingly sophisticated second-line studies (cross-sectional, functional, combined-modality approaches), which can be used to detect disease that has spread beyond the neck and, in some cases, shed light on its probable outcome.

Lack of association between obesity and aggressiveness of differentiated thyroid cancer

PurposeAim of this study was to evaluate the association between body mass index (BMI) and aggressive features of differentiated thyroid cancer (DTC) in a prospective cohort.MethodsPatients with DTC were prospectively enrolled at a tertiary referral center and grouped according to their BMI. Aggressive clinic-pathological features were analyzed following the American Thyroid Association Initial Risk Stratification System score.ResultsThe cohort was composed of 432 patients: 5 (1.2%) were underweight, 187 (43.3%) normal weight, 154 (35.6%) overweight, 68 (15.7%) grade 1 obese, 11 (2.5%) grade 2 obese and 7 (1.6%) grade 3 obese. No single feature of advanced thyroid cancer was more frequent in obese patients than in others. No significant correlation was found between BMI, primary tumor size (Spearman’s ρ − 0.02; p = 0.71) and ATA Initial Risk Stratification System score (ρ 0.03; p = 0.49), after adjustment for age. According to the multivariate logistic regression analysis, male gender and pre-surgical diagnosis of cancer were significant predictors of cancer with high or intermediate–high recurrence risk according to the ATA system (OR 2.06 and 2.51, respectively), while older age at diagnosis was a protective factor (OR 0.98), and BMI was not a predictor. BMI was a predictor of microscopic extrathyroidal extension only (OR 1.06).ConclusionsObesity was not associated with aggressive features in this prospective, European cohort of patients with DTC.