Elena Sabini

Treatment of advanced thyroid cancer with targeted therapies: ten years of experience

Thyroid cancer is rare, but it is the most frequent endocrine malignancy. Its prognosis is generally favorable, especially in cases of well-differentiated thyroid cancers (DTCs), such as papillary and follicular cancers, which have survival rates of approximately 95% at 40 years. However, 15-20% of cases became radioiodine refractory (RAI-R), and until now, no other treatments have been effective. The same problems are found in cases of poorly differentiated (PDTC) and anaplastic (ATC) thyroid cancers and in at least 30% of medullary thyroid cancer (MTC) cases, which are very aggressive and not sensitive to radioiodine. Tyrosine kinase inhibitors (TKIs) represent a new approach to the treatment of advanced cases of RAI-R DTC, MTC, PDTC, and, possibly, ATC. In the past 10 years, several TKIs have been tested for the treatment of advanced, progressive, and RAI-R thyroid tumors, and some of them have been recently approved for use in clinical practice: sorafenib and lenvatinib for DTC and PDTC and vandetanib and cabozantinib for MTC. The objective of this review is to present the current status of the treatment of advanced thyroid cancer with the use of innovative targeted therapies by describing both the benefits and the limits of their use based on the experiences reported so far. A comprehensive analysis and description of the molecular basis of these therapies, as well as new therapeutic perspectives, are reported. Some practical suggestions are given for both the choice of patients to be treated and their management, with particular regard to the potential side effects.

Anaplastic thyroid carcinoma: from clinicopathology to genetics and advanced therapies

Anaplastic thyroid carcinoma (ATC) is a rare malignancy, accounting for 1–2% of all thyroid cancers. Although rare, ATC accounts for the majority of deaths from thyroid carcinoma. ATC often originates in a pre-existing thyroid cancer lesion, as suggested by the simultaneous presence of areas of differentiated or poorly differentiated thyroid carcinoma. ATC is characterized by the accumulation of several oncogenic alterations, and studies have shown that an increased number of oncogenic alterations equates to an increased level of dedifferentiation and aggressiveness. The clinical management of ATC requires a multidisciplinary approach; according to recent American Thyroid Association guidelines, surgery, radiotherapy and/or chemotherapy should be considered. In addition to conventional therapies, novel molecular targeted therapies are the most promising emerging treatment modalities. These drugs are often multiple receptor tyrosine kinase inhibitors, several of which have been tested in clinical trials with encouraging results so far. Accordingly, clinical trials are ongoing to evaluate the safety, efficacy and effectiveness of these new agents. This Review describes the updated clinical and pathological features of ATC and provides insight into the molecular biology of this disease. The most recent literature regarding conventional, newly available and future therapies for ATC is also discussed.

Lenvatinib and other tyrosine kinase inhibitors for the treatment of radioiodine refractory, advanced, and progressive thyroid cancer

Lenvatinib is a small oral molecule able to inhibit three of the extracellular and intracellular molecules involved in the modulation of angiogenesis and lymphangiogenesis: vascular endothelial growth factor receptor 1–3, fibroblast growth factor receptor 1–4, and platelet-derived growth factor receptor alpha. Since it is also able to inhibit the REarranged during Transfection oncogene and the protooncogene c-KIT, this drug can also be used to control tumor cell proliferation. The maximum tolerated dose, as demonstrated in Phase I studies, is 25 mg daily. The drug is rapidly absorbed with maximum concentrations achieved within 3 and 5 hours after administration in fasting and nonfasting treated patients, respectively. The most common adverse events, reported in Phase I study and confirmed in the subsequent Phase II and III studies, are hypertension, proteinuria, and gastrointestinal symptoms such as nausea, diarrhea, and stomatitis. In Phase I studies, efficacy of lenvatinib in solid tumors was demonstrated, and these encouraging results have led to the development of a Phase II study using lenvatinib in advance radioiodine-refractory differentiated thyroid cancer (DTCs) patients. Since an overall response rate of 50% was reported, this study also confirmed the efficacy of lenvatinib in DTCs patients with an acceptable toxicity profile. Recently, a Phase III study in patients with DTCs (SELECT study) demonstrated the lenvatinib efficacy in prolonging progression-free survival with respect to the placebo (18.3 vs 3.6 months; P<0.001). Although there was no statistically significant difference in the overall survival of the entire group, this result was observed when the analysis was restricted to both the follicular histotype and the group of senior patients (>65 years). The study confirmed that the most common side effects of this drug are hypertension, diarrhea, decreased appetite, weight loss, nausea, and proteinuria. In this review, we report the results of the main studies on lenvatinib efficacy in patients with advanced and progressive thyroid cancer, mainly in DTCs but also in medullary and anaplastic thyroid cancer. We also compared the efficacy of lenvatinib with that of other tyrosine kinase inhibitors, mainly sorafenib, already tested in the same type of patient population.

VARIABLES AFFECTING THE LONG-TERM OUTCOME OF GRAVES ORBITOPATHY FOLLOWING HIGH-DOSE INTRAVENOUS GLUCOCORTICOID PULSE THERAPY IN PATIENTS NOT TREATED WITH ORBITAL RADIOTHERAPY.

OBJECTIVE Intravenous (iv) glucocorticoids (GC) (ivGC) are used for active Graves orbitopathy (GO), but factors affecting GO outcome are poorly understood. We performed a retrospective study to investigate the variables affecting GO after ivGC. METHODS We evaluated 83 consecutive GO patients treated with ivGC but not orbital radiotherapy (ORT) and re-examined them after a median of 47 months. The endpoints were the relationships between GO outcome or additional treatments with age, sex, smoking habits, thyroid volume, thyroid treatment, time since thyroid treatment, antithyroid-stimulating hormone receptor antibodies (TRAb), GO duration, GO features, and follow-up time. RESULTS GO features improved after treatment, resulting in moderate and marked amelioration in ~75% and ~41% of patients respectively. By multivariate analysis, a moderate GO improvement correlated with diplopia at first observation, which was more severe in responders. A marked GO improvement correlated with time between first and last observation and time after thyroid treatment, which were longer in responders. This likely reflected the combination of an early effect of GC and a late, spontaneous improvement of GO, as shown by analyses of GO outcome at various time points. Additional treatments after ivGC correlated by multivariate analysis with eyelid aperture, diplopia and NOSPECS score (NOSPECS stands for no GO signs [N], only eyelid sign [O], soft tissue involvement [S], proptosis [P], extraocular motility restriction [E], corneal involvement [C], and sight loss [S]) at first observation, which were more severe in responders. CONCLUSION Our study shows that response to ivGC increases with time, likely reflecting the known tendency of GO to improve spontaneously, and is more pronounced when GO is more severe to begin with, which is associated with more additional treatments. ABBREVIATIONS ANOVA = analysis of variance CAS = clinical activity score GC = glucocorticoids GO = Graves orbitopathy 131I = radioactive iodine iv = intravenous ivGC = high-dose intravenous glucocorticoid pulse therapy MMI = methimazole OD = orbital decompression ORT = orbital radiotherapy TRAb = antithyroid-stimulating hormone receptor antibodies.

Natural history of graves’ orbitopathy after treatment

Intravenous glucocorticoids are used for Graves’ orbitopathy, alone or associated with/followed by additional treatments (orbital radiotherapy, orbital decompression, palpebral or eye surgery). However, the relation between associated/additional treatments and other variables with Graves’ orbitopathy outcome following intravenous glucocorticoids is not clear. Thus, the present study was conducted to investigate retrospectively the impact of associated/additional treatments and other variables on Graves’ orbitopathy outcome after intravenous glucocorticoids. We evaluated 226 untreated Graves’ orbitopathy patients. Following first observation, patients were given intravenous glucocorticoids and re-examined after a median of 46.5 months. The end-points were the relation between Graves’ orbitopathy outcome, outcome of NOSPECS score and of the single Graves’ orbitopathy features with several variables, including associated/additional treatments. All Graves’ orbitopathy features improved significantly after treatment. Overall, Graves’ orbitopathy improved in ~60 % of patients (responders), whereas it was stable or worsened in ~40 % of patients (non-responders). Time between first and last observation and clinical activity score at first observation correlated significantly with Graves’ orbitopathy outcome. The outcomes of NOSPECS, eyelid aperture, clinical activity score and diplopia correlated with time between the first and last observation. The NOSPECS outcome correlated with gender. The outcomes of proptosis, eyelid aperture and visual acuity correlated with orbital decompression. The outcome of diplopia correlated with orbital radiotherapy. Taking into account the limitations of retrospective investigations, our findings confirm that time (i.e. the natural history of Graves’ orbitopathy) is a key factor in determining the long-term outcome of Graves’ orbitopathy, radiotherapy is effective for diplopia, and orbital decompression is followed by an amelioration of several Graves’ orbitopathy features.

Association of T and B Cells Infiltrating Orbital Tissues With Clinical Features of Graves Orbitopathy

Importance Graves orbitopathy (GO) responds to immunosuppressive treatments when clinically active but poorly when inactive. In other autoimmune diseases, response has been ascribed to a reduction in lymphocytes infiltrating the target organ. It is not known whether active vs inactive GO differs in this regard, which would help in understanding the link between GO immunologic features and clinical behavior. Objective To investigate the association between orbital lymphocytic infiltrate and GO clinical features. Design, Setting, and Participants A cohort study aimed at assessing the extent and immunohistochemical phenotype of orbital lymphocytes and associating it with the ophthalmologic features of GO, especially its clinical activity score (CAS), was conducted at a tertiary referral center. Twenty consecutive patients with GO who underwent orbital decompression were included. The study was conducted from January 1 to May 31, 2017. Exposures Orbital tissue histology and immunohistochemistry testing as well as ophthalmologic evaluation. Main Outcomes and Measures Association between CAS and orbital lymphocytes, analyzed as total number of lymphocytes and main lymphoid subsets. Results The patient population included 8 men and 12 women, all of white race, with a mean (SD) age of 46 (13) years. With an established cutoff value of 300 lymphoid cells per tissue sample, lymphocytes above this value were found in orbital tissues of 9 of 20 patients (45%), often organized into distinct foci. The lymphocytes comprised a mixture of T (CD3-positive) and B (CD20-positive) cells, suggesting a mature, polyclonal autoimmune response. In a simple linear regression model, the total number of lymphocytes, as well as the number of CD3- and CD20-positive subsets, correlated with CAS (R = 0.63; 95% CI, 0.27-0.84; P = .003; R = 0.59; 95% CI, 0.20-0.82; P = .006; and R = 0.65; 95% CI, 0.30-0.85; P = .002, respectively). In a multiple linear regression model, lymphocytes maintained their effect on CAS when adjusted for 2 additional variables that were correlated with CAS—smoking and GO duration—highlighting even more the important role of orbital lymphocytes in affecting CAS (total number: R = 0.58; 95% CI, 0.18-0.82; P = .01; CD3-positive: R = 0.58; 95% CI, 0.17-0.82; P = .01; and CD20-positive: R = 0.59; 95% CI, 0.19-0.83; P = .01). Conclusions and Relevance This study shows a correlation between T and B lymphocytes infiltrating orbital tissues and the activity of GO, possibly enhancing our understanding of the association between GO immunologic features and clinical expression.

Occurrence of Graves’ Orbitopathy and Graves’ Hyperthyroidism after a Trauma to the Eye

Background: Graves’ orbitopathy (GO) is believed to be the consequence of autoimmunity against antigens that are present both in the thyroid and orbital tissues. Massive release of thyroid antigens causes the appearance or deterioration of GO in patients with Graves’ hyperthyroidism (GH), as it occurs following radioiodine treatment. In theory, a similar release of autoantigens may occur at the eye level, for example due to an orbital trauma or surgical manipulation. To our knowledge, this is the first report of a case of de novo appearance of GO and then GH after an eye trauma, possibly reflecting spreading of autoantigens and activation of the immune system against shared orbital and thyroid antigens. Case Report: An otherwise healthy, 57-year-old man presented 6 months after the appearance of a monolateral right orbitopathy, which occurred 40 days after a trauma in the ipsilateral eye. His thyroid function was normal, with positive serum anti-TSH receptor autoantibodies. The thyroid was normal on ultrasound. A month later he developed hyperthyroidism and orbitopathy in the left eye. Discussion: The development of GO after an eye trauma may reflect tissue damage with release of autoantigens and consequent autoimmunity in a predisposed individual (our patient had a familial history of autoimmune thyroid disease). The subsequent development of hyperthyroidism is in keeping with the hypothesis that GH and GO are due to autoimmunity against antigens present both in the thyroid and in orbital tissues.

Does Graves’ Orbitopathy Ever Disappear Answers to an Old Question

Objectives: There is a general belief that Graves’ orbitopathy (GO) is a “chronic” disease, namely that patients’ eyes do not return to how they were before GO appeared. Here, we investigate this issue from both the patient’s and the physician’s point of view. Study Design: We studied the disappearance of GO, regardless of treatment, in all consecutive patients with a GO history of at least 10 years who came for a follow-up visit over a period of 5 years. Patients underwent an ophthalmological examination and were asked to answer a questionnaire on self-perception related to GO. Results: We studied 99 consecutive patients with a GO duration ≥10 years. Between the first and the last observation, patients received several types of treatment for their thyroid disease and/or for GO. At the end of follow-up, GO was considered disappeared based on objective criteria in 8 patients (∼8%) and based on subjective criteria in 24 patients (∼24%). When we considered both subjective and objective criteria, only 2 patients (∼2%) had all criteria fulfilled and could be considered as GO-free. Conclusions: GO is a chronic disease in the vast majority of patients. Even after a very long time since its onset, complete disappearance is rare, although a minority of patients believe they do not have GO anymore and an even lower proportion do not have relevant GO signs. Our findings have obvious implications in patient management and counseling.