Locally unresectable differentiated thyroid cancer: outcomes and perspectives.

PURPOSE: Differentiated thyroid cancer (DTC) patients with an unresectable primary tumor cannot benefit from curative surgery, and radioiodine treatment for locoregional and distant disease is not possible with the thyroid gland still in place. Due to local invasion, these patients cannot be included in clinical trials, so that treatment options are limited. The aim of this study was to describe the characteristics and the prognosis of patients with these locally unresectable DTC. PATIENTS AND METHODS: A retrospective and multicentric analysis of consecutive cases of unresectable DTC diagnosed between 2000 and 2015 was performed. RESULTS: The study population consisted in 22 patients, 13 females (59%); median age: 77 years (range: 52-91). Thyroid tumors were papillary in six, follicular in seven, Hürthle cell in one and poorly differentiated in eight patients. Patients were treated with external beam radiation therapy (EBRT) (57%), locoregional therapy of distant metastases (41%), cytotoxic chemotherapy (38%) and tyrosine kinase inhibitors (TKIs) (33%). TKI treatment resulted in median disease control duration of 7 months with a grade 3-4 toxicity rate of 44%. Only one patient had a total thyroidectomy after neo-adjuvant EBRT. The 1, 3 and 5-year cumulative survival rate was 81%, 27.7% and 21.5%, respectively. The cause of death was DTC in 11 cases (local progression in 7), and to other causes in 7 cases; no patient died from treatment toxicity. CONCLUSIONS: Clinical trials and approved treatments are lacking for unresectable DTC. TKI treatment may allow prolonged disease control with acceptable toxicity.

French Endocrine Society Guidance on endocrine side effects of immunotherapy.

The management of cancer patients has changed due to the considerably more frequent use of immune checkpoint inhibitors (ICPIs). However, the use of ICPI has a risk of side effects, particularly endocrine toxicity. Since the indications for ICPI are constantly expanding due to their efficacy, it is important that endocrinologists and oncologists know how to look for this type of toxicity and how to treat it when it arises. In view of this, the French Endocrine Society initiated the formulation of a consensus document on ICPI-related endocrine toxicity. In this paper, we will introduce data on the general pathophysiology of endocrine toxicity, and we will then outline expert opinion focusing primarily on methods for screening, management and monitoring for endocrine side effects in patients treated by ICPI. We will then look in turn at endocrinopathies that are induced by ICPI including dysthyroidism, hypophysitis, primary adrenal insufficiency and fulminant diabetes. In each chapter, expert opinion will be given on the diagnosis, management and monitoring for each complication. These expert opinions will also discuss the methodology for categorizing these side effects in oncology using 'common terminology criteria for adverse events' (CTCAE) and the difficulties in applying this to endocrine side effects in the case of these anti-cancer therapies. This is shown in particular by certain recommendations that are used for other side effects (high-dose corticosteroids, contraindicated in ICPI for example) and that cannot be considered as appropriate in the management of endocrine toxicity, as it usually does not require ICPI withdrawal or high-dose glucocorticoid intake.

Does the RET variant G691S influence the features of sporadic medullary thyroid carcinoma?

OBJECTIVE: The RET (rearranged during transfection) proto-oncogene G691S variant is over-represented in the germline of patients with sporadic medullary thyroid carcinoma (sMTC) vs. normal controls but so far is not associated with any medical or pathological features of the tumour. The aim of our study was to assess the influence of this variant on the age of onset, clinical, biological and pathological features of sMTC. DESIGN AND PATIENTS: One hundred patients with histologically proven MTC, for whom the germline genetic analysis of RET was negative and medical records were available, were included in the study. RESULTS: Patients with the heterozygous GS variant or the homozygous SS variant (n = 36) were on average 8.0 years younger than patients with the wild-type GG variant (n = 64, mean age 43.9 vs. 51.9 years, P < 0.01). The former group did not differ from the wild-type group in terms of MTC size, prevalence of C-cell hyperplasia (CCH) or papillary thyroid carcinoma (PTC). However, the prevalence of an increased preoperative basal calcitonin (bCT) level (> 1000 pg/ml) was 2.75-fold higher in the patients with the GS or SS variant than in those with the wild-type variant (P < 0.001). The proportion of patients with lymph node metastases was also higher in the former group (P < 0.05). Multivariate analysis confirmed that the presence of the RET variant is independently associated with higher preoperative bCT values (P = 0.011). CONCLUSIONS: Our data demonstrate that the RET G691S variant could modulate the age of onset of sMTC as demonstrated previously for familial tumours. Moreover, this variant is an independent predictor of a higher basal calcitonin synthesis rate in patients with sMTC.

[Anaplastic thyroid carcinoma]. / Cancers anaplasiques de la thyroïde.

Anaplastic thyroid carcinoma may represent the ultimate dedifferentiation step of thyroid tumorigenesis and is one of the poorest cancers in human. It accounts for less than 2% of thyroid cancers and affects older patients in their sixth to eighth decade. Usual clinical presentation is a rapidly growing thyroid mass invading surrounding structures with compressive symptoms. Cervical lymph nodes enlargement and distant metastases occur frequently. Though cytological results obtained by fine needle aspiration may be suggestive of diagnosis, tissue biopsy for immunohistochemical study can be necessary to exclude lymphoma and to validate aggressive therapies. Patients developing anaplastic thyroid cancer must be referred urgently in cancer centers to plan multimodality therapeutic approach depending on their performance status. The treatment regimen combines surgery when feasible, hyperfractionated and accelerated external beam radiotherapy and doxorubicin based chemotherapy. Such treatment can provide control of locoregional disease but does not impact on overall survival in patients with distant metastases. The prognosis is dismal with a mean survival of four to nine months after diagnosis. Long survivors are patients with emerging disease presenting a resectable tumor and receiving adjuvant radiotherapy and/or chemotherapy. Therapeutic researches investigate redifferenciation strategies and targeted therapies to inhibit EGF receptors and neoplastic angiogenesis. Primary prevention of this lethal disease may consist of adequate treatment of differentiated thyroid cancers and goiters in elderly.

Thyrotoxicosis revealing metastases of unrecognized thyroid cancer: a report on two cases.

We report two cases of thyrotoxicosis-revealing functional metastases of a follicular carcinoma that extended to the bones, liver and kidneys in one case and to the lungs in the other. Both patients had undergone surgical intervention for a thyroid nodule more than 15 years before the diagnosis of thyrotoxicosis and metastatic dissemination. In both the cases, the carcinoma was not recognized by the pathologist after the first surgical intervention, but was finally diagnosed several years later due to the occurrence of thyrotoxicosis. Iodine-131 therapy was effective at suppressing the thyrotoxicosis in both the patients. The effectiveness on the metastatic extension was very different for each patient: in the first case, the patient died a few years later without any control of the metastatic tissue. For the second patient, the metastases disappeared a few months after radioiodine treatment, with the patient still in remission more than 10 years later. The physiopathology and the evolution of these two cases are discussed with the data available in the literature.

Risk-benefit ratio for TSH- suppressive Levothyroxine therapy in differentiated thyroid cancer.

In the setting of differentiated thyroid cancer (DTC) management, < 0.1 mU/L TSH suppression has been proven to be beneficial for patients likely to have microscopic or macroscopic disease, as TSH has a direct trophic effect on thyroid cancer cells. However, the optimal degree of TSH reduction remains unclear for other categories of DTC patients with better prognosis. Excessive thyroid hormone replacement can lead to atrial fibrillation and osteoporosis. Therefore, levothyroxine dose should be carefully adjusted with respect to underlying individual health status, dynamically reassessed risk of relapse and medical monitoring. Future guidelines should give priority to a tailored approach to TSH suppression therapy in DTC patients.

Positive predictive value of serum thyroglobulin levels, measured during the first year of follow-up after thyroid hormone withdrawal, in thyroid cancer patients.

The follow-up of patients with papillary and follicular thyroid carcinoma after thyroidectomy and radioiodine ablation is mainly based on serum thyroglobulin (Tg) level deter-mination. The positive predictive value (PPV) of serum Tg level after thyroid hormone withdrawal, measured during the first 6-12 months of follow-up (initial off L-T(4) Tg), was studied in 256 consecutive differentiated thyroid cancer patients. All underwent a total thyroidectomy and 3.7 GBq (131)I ablation; 37 patients had an elevated initial off L-T(4) Tg level. This study focuses on these 37 patients, 9 of whom had a clinical recurrence. The present data confirm that in this selected cohort of patients, 74-185 MBq (131)I-total body scan (TBS) has no clinical interest in the initial work-up and during the subsequent follow-up because it was negative in all patients, except in one with recurrent disease. The PPV of initial serum off L-T(4) Tg level above 5 ng/ml and 10 ng/ml was 42% and 53%, respectively; this PPV was only 50% at the time of recurrence or subsequent control. This relatively low PPV is related to the low recurrence rate in this series of patients, despite a prolonged follow-up, and to the subsequent decrease of serum Tg level in 14 of 37 (38%) patients in the absence of any further treatment. In contrast, the PPV of the increasing slope of serum Tg levels obtained after thyroid hormone withdrawal (83%) was excellent. In conclusion, we confirm that (131)I-TBS has a limited interest for the follow-up of thyroid cancer patients. Follow-up should rely on serum Tg level and prognostic parameters; however, initial serum Tg may be produced by thyroid tissues of various significance, an increase at two consecutive determinations indicating disease progression and a decrease being related to late effects of therapy. The best PPV is brought by the slope of serum Tg levels.

[Thyroid nodule, cancer and pregnancy]. / Nodule thyroïdien, cancer et grossesse.

Pregnancy is a favorable condition for thyroid nodule formation and growth since iodine balance may be negative in addition to increasing production of hormones with thyroid stimulatory activity. Thyroid nodules may be discovered in pregnant women on routine examination: what is the risk for a nodule to be malignant, how should it be investigated? In case thyroid cancer is suspected, is there an impact of pregnancy on the tumor outcome and what treatments are available? Infrequently, diagnoses of toxic autonomous nodules or medullary carcinomas may be supported by elevated serum calcitonin or suppressed TSH value. Ultrasonography scanning and fine-needle aspiration biopsy (FNAB) best help to monitor thyroid nodules and guide their management. Toxic autonomous nodules can be either surgically resected in the second trimester of pregnancy or treated by percutaneous alcohol injection. When cytology findings are benign or indecisive, solid nodules require follow-up by neck palpation, in association to repeat ultrasonographic study and nodule aspiration as necessary. In this setting, thyroxine administered in small doses or iodine supply merit consideration. If FNAB samples are suggestive of suspicious or malignant lesions, thyroidectomy can be performed through the second trimester or delayed after delivery, depending on the pregnancy term. Observations of pregnant women with a rapid growing differentiated thyroid cancer have been reported. However, in matched studies comparing pregnant and nonpregnant women recurrence risk and cancer mortality are not significantly different.

Chromogranin A assay in clinical practice.

Chromogranins belong to the family of secretory chromogranin and secretogranin proteins. They are found in secretory vesicles throughout the neuroendocrine system. Chromogranin A (CgA) is the main component. CgA acts as a prohormone submitted to processes of degradation through which active peptides are generated. CgA has auto, para and endocrine functions. It is widely used as an immunohistochemical marker. Despite the lack of international standardization, and the lack of an accurate definition of the diagnostic cut-off levels, some CgA assays are reliable. Numerous studies have suggested that CgA determination may be of interest for the diagnosis and the follow-up of various endocrine tumors. Plasma levels of this general marker are proportional to tumor mass. The localization of the primitive tumor, the presence of associated hormonal secretions and possible renal failure and/or hypergastrinemia must be taken into consideration for proper interpretation of CgA levels. New clinical indications are emerging for the evaluation of stress in intensive care units and the assessment of cardiovascular risk. New assays estimating the concentration of active peptides are under development.

Hypercalcitonemia revealing a somatostatinoma.

Somatostatinoma are rare well-differentiated endocrine tumors with malignant behavior arising from the pancreas and duodenum. They are defined by somatostatin positive immunostaining of the majority of tumor cells. The main clinical features are diabetes, diarrhea and biliary lithiasis related to somatostatin production. Somatostatinoma secreting both calcitonin and somatostatin may be unrecognized as a small number of such observations have been published. We report the case of a 57- year-old woman referred for weight loss, diarrhea and worsening diabetes. Computer tomography scan revealed multiple hypervascular liver lesions suggestive of metastases. High plasma calcitonin level was evidenced, with normal chromogranin-A value, and high plasma somatostatin results lately communicated. Calcitonin secretion of extra-thyroidal origin was suspected leading to the identification of a pancreatic mass by further multiphase CT. The patient underwent left pancreatectomy with surgical hepatic resection. Histological and immunostaining studies confirmed definitive diagnosis of somatostatinoma secreting both somatostatin and calcitonin. Plasma calcitonin should be measured in the assessment of duodeno-pancreatic endocrine neoplasm. Calcitonin determination is available, more reproducible than other specific pancreatic endocrine markers and could be effective for diagnosis and follow-up of such foregut-derived endocrine neoplasia.

Merits and pitfalls of mifepristone in Cushing's syndrome.

OBJECTIVE: Mifepristone is the only available glucocorticoid receptor antagonist. Only few adult patients with hypercortisolism were treated to date by this drug. Our objective was to determine effectiveness and tolerability of mifepristone in Cushing's syndrome (CS). DESIGN: Retrospective study of patients treated in seven European centers. METHODS: Twenty patients with malignant (n=15, 12 with adrenocortical carcinoma, three with ectopic ACTH secretion) or benign (n=5, four with Cushing's disease, one with bilateral adrenal hyperplasia) CS were treated with mifepristone. Mifepristone was initiated with a median starting dose of 400 mg/day (200-1000). Median treatment duration was 2 months (0.25-21) for malignant CS, and 6 months (0.5-24) for benign CS. Clinical (signs of hypercortisolism, blood pressure, signs of adrenal insufficiency), and biochemical parameters (serum potassium and glucose) were evaluated. RESULTS: Treatment was stopped in one patient after 1 week due to severe uncontrolled hypokalemia. Improvement of clinical signs was observed in 11/15 patients with malignant CS (73%), and 4/5 patients with benign CS (80%). Psychiatric symptoms improved in 4/5 patients within the first week. Blood glucose levels improved in 4/7 patients. Signs of adrenal insufficiency were observed in 3/20 patients. Moderate to severe hypokalemia was observed in 11/20 patients and increased blood pressure levels in 3/20 patients. CONCLUSION: Mifepristone is a rapidly effective treatment of hypercortisolism, but requires close monitoring of potentially severe hypokalemia, hypertension, and clinical signs of adrenal insufficiency. Mifepristone provides a valuable treatment option in patients with severe CS when surgery is unsuccessful or impossible.