Outcomes and Prognostic Factors in Radioiodine Refractory Differentiated Thyroid Carcinomas.

BACKGROUND: Outcomes vary among patients with radioiodine refractory (RR) differentiated thyroid cancer (DTC). The prognostic factors for survival are not well-known, resulting in difficulty in selecting patients for new targeted therapies. We assessed overall survival (OS) and cancer-specific survival (CSS) from RR-DTC to identify prognostic factors associated with survival. PATIENTS AND METHODS: The data on all cases of metastatic RR-DTC treated in our center from 1990 to 2011 were retrospectively reviewed. Survival was estimated using the Kaplan-Meier method; associated prognostic factors were assessed using Cox's model. RESULTS: Of 153 cases of metastatic DTC, 59% (n = 91) met a criterion for RR: that is, 60% (n = 55) had at least 1 metastasis without (131)I uptake; 21% (n = 19) had progressive disease (PD) despite (131)I; 19% (n = 17) had persistent disease despite a cumulative activity of (131)I of ≥600 mCi. After the diagnosis of RR, median OS was 8.9 years (95% confidence interval [CI]: 5.4-NR); median CSS was 9.6 years (95% CI: 6.01-NR). In multivariate analyses, PD despite (131)I as a criterion for RR disease and the time from initial diagnosis of DTC to diagnosis of RR <3 years were the only independent prognostic factors for poor OS and CSS. Thyroglobulin doubling time (Tg-DT) was assessed in 31 of 91 cases. Among the 11 patients with Tg-DT for <1 year or undetectable Tg, 6 deaths occurred, whereas only 3 died of 20 patients with Tg-DT >1 year or negative Tg-DT. CONCLUSION: The identification of prognostic factors for decreased survival in RR-DTC may improve the selection of patients for targeted agents. IMPLICATIONS FOR PRACTICE: This study shows a great heterogeneity in terms of prognosis in radioiodine refractory differentiated thyroid carcinoma. Poorer prognosis is observed in patients with tumor progression or with a diagnosis of radioiodine resistance within 3 years after the initial diagnosis of thyroid cancer. Those findings could lead to improvements in the selection of patients for targeted therapies.

From Nf1 to Sdhb knockout: Successes and failures in the quest for animal models of pheochromocytoma.

Pheochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumors characterized by a high frequency of hereditary forms. Based on transcriptome classification, PPGL can be classified in two different clusters. Cluster 1 tumors are caused by mutations in SDHx, VHL and FH genes and are characterized by a pseudohypoxic signature. Cluster 2 PPGL carry mutations in RET, NF1, MAX or TMEM127 genes and display an activation of the MAPK and mTOR signaling pathways. Many genetically engineered and allografted mouse models have been generated these past 30 years to investigate the mechanisms of PPGL tumorigenesis and test new therapeutic strategies. Among them, only Cluster 2-related models have been successful while no Cluster 1-related knockout mouse was so far reported to develop a PPGL. In this review, we present an overview of existing, successful or not, PPGL models, and a description of our own experience on the quest of Sdhb knockout mouse models of PPGL.

Vascular pattern analysis for the prediction of clinical behaviour in pheochromocytomas and paragangliomas.

Pheochromocytomas (PCCs) are neuroendocrine tumors arising from chromaffin cells of the adrenal medulla. Related tumors that arise from the paraganglia outside the adrenal medulla are called paragangliomas (PGLs). PCC/PGLs are usually benign, but approximately 17% of these tumors are malignant, as defined by the development of metastases. Currently, there are no generally accepted markers for identifying a primary PCC or PGL as malignant. In 2002, Favier et al. described the use of vascular architecture for the distinction between benign and malignant primary PCC/PGLs. The aim of this study was to validate the use of vascular pattern analysis as a test for malignancy in a large series of primary PCC/PGLs. Six independent observers scored a series of 184 genetically well-characterized PCCs and PGLs for the CD34 immunolabeled vascular pattern and these findings were correlated to the clinical outcome. Tumors were scored as malignant if an irregular vascular pattern was observed, including vascular arcs, parallels and networks, while tumors with a regular pattern of short straight capillaries were scored as benign. Mean sensitivity and specificity of vascular architecture, as a predictor of malignancy was 59.7% and 72.9%, respectively. There was significant agreement between the 6 observers (mean κ = 0.796). Mean sensitivity of vascular pattern analysis was higher in tumors >5 cm (63.2%) and in genotype cluster 2 tumors (100%). In conclusion, vascular pattern analysis cannot be used in a stand-alone manner as a prognostic tool for the distinction between benign and malignant PCC, but could be used as an indicator of malignancy and might be a useful tool in combination with other morphological characteristics.

Multi-omics analysis defines core genomic alterations in pheochromocytomas and paragangliomas.

Pheochromocytomas and paragangliomas (PCCs/PGLs) are neural crest-derived tumours with a very strong genetic component. Here we report the first integrated genomic examination of a large collection of PCC/PGL. SNP array analysis reveals distinct copy-number patterns associated with genetic background. Whole-exome sequencing shows a low mutation rate of 0.3 mutations per megabase, with few recurrent somatic mutations in genes not previously associated with PCC/PGL. DNA methylation arrays and miRNA sequencing identify DNA methylation changes and miRNA expression clusters strongly associated with messenger RNA expression profiling. Overexpression of the miRNA cluster 182/96/183 is specific in SDHB-mutated tumours and induces malignant traits, whereas silencing of the imprinted DLK1-MEG3 miRNA cluster appears as a potential driver in a subgroup of sporadic tumours. Altogether, the complete genomic landscape of PCC/PGL is mainly driven by distinct germline and/or somatic mutations in susceptibility genes and reveals different molecular entities, characterized by a set of unique genomic alterations.

(18)F-fluorodeoxyglucose positron emission tomography to assess response after radiation therapy in anaplastic thyroid cancer.

AIM: To assess the interest of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET/CT) to evaluate the tumor response after radiotherapy (RT) in anaplastic thyroid cancer (ATC) patients. METHODS AND MATERIALS: 92 patients were treated for ATC at our institution from 1987 to 2012, out of which 64 (70%) received an aggressive multimodal treatment and 28 (30%) a palliative treatment. In the multimodal treatment group, curative-intended surgery, chemotherapy, and RT were delivered in 35 (55%), 59 (92%), and 56 (88%) patients. The maximum standardized uptake value (SUVmax) was determined in tumor (T), nodes (N) and metastases (M) in each available (18)F-FDG PET/CT. RESULTS: The median follow-up was 3.2years. The 1-year actuarial overall survival (OS) was 18% (median: 5.2months) in the entire population and 27% (median: 7months) in the multimodal treatment group. In the multivariate analysis, RT, surgery, and pre-RT chemotherapy independently predicted for OS, with HRs respectively of 0.1, 0.3, and 0.5. Quantification of FDG uptake with SUVmax was assessable in 26 (40%), 19 (30%), and 25 (39%) of (18)F-FDG PET/CT performed initially (prior to any treatment), prior to RT, and after RT, respectively. Mean SUVmax significantly decreased in T (p<0.001), but not in N (p=0.1) and M (p=0.3) during the assessment period, which might be related to the local effect of RT. Comparing pre- and post-RT (18)F-FDG PET/CT, the T mean relative SUVmax decrease was lower (23±54%) in the 4 patients that had a local relapse (LR) as compared with others in the 12 others patients (62±33%; p=0.3). A relative SUVmax decrease inferior to 20% significantly predicted for LR (p=0.02). CONCLUSION: The prognosis of ATC patients remains dismal despite an aggressive multimodal treatment. Although our results were not significant, (18)F-FDG PET/CT could potentially serve as a surrogate marker of treatment response in ATC.

Postoperative fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography: an important imaging modality in patients with aggressive histology of differentiated thyroid cancer.

BACKGROUND: Aggressive histopathologic subtypes of differentiated thyroid cancer (DTC) are fluorodeoxyglucose (FDG)-avid tumors and are at high risk for persistent/recurrent disease. In these patients, fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is performed in cases of suspicion of recurrence based on thyroglobulin (Tg) levels or thyroglobulin antibodies (TgAb). The goals of this study were to evaluate the sensitivity of systematic postoperative FDG-PET/CT and to identify risk factors for abnormal FDG-PET/CT. METHODS: Single-center retrospective study of 38 consecutive patients (16 males, 22 females; mean age, 57 years) with aggressive histology DTC, without known persistent disease at the time of postoperative radioactive iodine (RAI) ablation. The most frequent aggressive histologic subtypes were tall cell papillary carcinoma (45%) and poorly differentiated carcinoma (42%). RESULTS: A total of 86 lesions were found in 20 (53%) patients, distributed in 33 organs. FDG-PET/CT and the postablation whole-body scan (RAI WBS) showed persistent disease in 15 and 12 patients, respectively. FDG-PET/CT was more sensitive than WBS for the detection of individual lesions (69% vs. 59%). Both imaging techniques were complementary with 41% of the lesions detected only by FDG-PET/CT and 31% only by RAI WBS. The only risk factor of abnormal FDG-PET/CT was a stimulated Tg level (Tg/TSH) measured at ablation >10 ng/mL with persistent disease showing FDG uptake in 72% of the patients with a Tg/TSH >10 ng/mL and in 10% of the patients with Tg/TSH ≤10 ng/mL. CONCLUSION: Postoperative FDG-PET/CT should be performed routinely in patients with aggressive histology DTC.

SDHD immunohistochemistry: a new tool to validate SDHx mutations in pheochromocytoma/paraganglioma.

CONTEXT: Pheochromocytomas (PCC) and paragangliomas (PGL) may be caused by a germline mutation in 12 different predisposing genes. We previously reported that immunohistochemistry is a useful approach to detect patients harboring SDHx mutations. SDHA immunostaining is negative in SDHA-mutated tumors only, while SDHB immunostaining is negative in samples mutated on all SDHx genes. In some cases of SDHD or SDHC-mutated tumors, a weak diffuse SDHB labeling has however been described. OBJECTIVE: Here, we addressed whether the same procedure could be applicable to detect patients with germline SDHD mutations, by testing two new commercially available anti-SDHD antibodies. DESIGN AND METHODS: We performed a retrospective study on 170 PGL/PCC in which we investigated SDHD and SDHB expression by immunohistochemistry. RESULTS: SDHx-mutated PGL/PCC showed a completely negative SDHB staining (23/27) or a weak cytoplasmic background (4/27). Unexpectedly, we observed that SDHD immunohistochemistry was positive in SDHx-deficient tumors and negative in the other samples. Twenty-six of 27 SDHx tumors (including the four weakly stained for SDHB) were positive for SDHD. Among non-SDHx tumors, 138/143 were positive for SDHB and negative for SDHD. Five cases showed a negative immunostaining for SDHB, but were negative for SDHD. CONCLUSION: Our results demonstrate that a positive SDHD immunostaining predicts the presence of an SDHx gene mutation. Because SDHB negative immunostaining is sometimes difficult to interpret in the case of background, the addition of SDHD positive immunohistochemistry will be a very useful tool to predict or validate SDHx gene variants in PGL/PCC.

Postoperative radioactive iodine administration for differentiated thyroid cancer patients.

PURPOSE OF REVIEW: Radioactive iodine (RAI) is administered postoperatively to the majority of thyroid cancer patients. No available study has demonstrated any benefit in low-risk patients. RECENT FINDINGS: RAI should be used selectively in low and intermediate-risk patients, based on the surgical and pathological reports and on postoperative serum thyroglobulin level and neck ultrasonography. When used, a low activity (30 mCi) is administered following recombinant human thyrotropin stimulation. High-risk patients are treated with a high activity of RAI (100 mCi or more). SUMMARY: RAI is not administered in many low-risk patients who can be reliably followed up with serum thyroglobulin determination on L-thyroxine treatment and neck ultrasonography. RAI may be administered in case of abnormality, and this delay will not reduce the chance of cure.

Post-operative neck ultrasound and risk stratification in differentiated thyroid cancer patients with initial lymph node involvement.

OBJECTIVE: Cervical ultrasound (US) scan is a key tool for detecting metastatic lymph nodes (N1) in patients with papillary thyroid cancer (PTC). N1-PTC patients are stratified as intermediate-risk and high-risk (HR) patients, according to the American Thyroid Association (ATA) and European Thyroid Association (ETA) respectively. The aim of this study was to assess the value of post-operative cervical US (POCUS) in local persistent disease (PD) diagnosis and in the reassessment of risk stratification in N1-PTC patients. DESIGN: Retrospective cohort study. METHODS: Between 1997 and 2010, 638 N1-PTC consecutive patients underwent a systematic POCUS. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of POCUS for the detection of PD were evaluated and a risk reassessment using cumulative incidence functions was carried out. RESULTS: After a median follow-up of 41.6 months, local recurrence occurred in 138 patients (21.6%), of which 121 were considered to have PD. Sensitivity, specificity, NPV, and PPV of POCUS for the detection of the 121 PD were 82.6, 87.4 95.6, and 60.6% respectively. Cumulative incidence of recurrence at 5 years was estimated at 26% in ETA HR patients, 17% in ATA intermediate-risk patients, and 35% in ATA HR patients respectively. This risk fell to 9, 8, and 11% in the above three groups when the POCUS result was normal and to <6% when it was combined with thyroglobulin results at ablation. CONCLUSION: POCUS is useful for detecting PD in N1-PTC patients and for stratifying individual recurrence risk. Its high NPV could allow clinicians to tailor follow-up recommendations to individual needs.

Primary adrenal angiosarcoma and functioning adrenocortical adenoma: an exceptional combined tumor.

CONTEXT: Primary adrenal angiosarcoma is an extremely rare neoplasm, as are combined tumors within a given adrenal lesion. CLINICAL PRESENTATION AND INTERVENTION: A 35-year-old man presented with hypokalemic hypertension leading to the discovery of a 6 cm diameter malignant-appearing right adrenal tumor. The lesion displayed marked (18)F-fluorodeoxyglucose uptake on positron emission tomography scanning. Endocrine investigations revealed secretion of both cortisol and aldosterone by the neoplasm. The entire right adrenal gland along with the periadrenal fat tissue was removed during laparoscopic surgery. RESULTS: Histological examination revealed two intermingled tumor cell proliferations, namely an angiosarcoma and an adrenocortical adenoma. An extensive post-operative search revealed no other primary tumor site, nor metastases. The lesion was then considered to be a primary adrenal angiosarcoma combined with a secreting adrenocortical adenoma. The patient received four cycles of chemotherapy (adriamycin/ifosfamide). At 2-year follow-up, he is alive and well, with no sign of relapse. CONCLUSION: To the best of our knowledge, this is the first case of an adrenal neoplasm combining a primary angiosarcoma and a functioning adrenocortical adenoma.

A novel TMEM127 mutation in a patient with familial bilateral pheochromocytoma.

OBJECTIVE: In this report, we describe a new patient with unexplained familial bilateral pheochromocytoma. Following the recent description of TMEM127 as a new pheochromocytoma susceptibility gene, the aim of this study was to test the hypothesis of a causative TMEM127 gene mutation in this patient. DESIGN: Pheochromocytoma susceptibility genes were analyzed in germline DNA and losses of heterozygosity (LOH) assessed by BAC array comparative genomic hybridization in tumor DNA. SDHB expression and S6 kinase (S6K) phosphorylation were analyzed by immunohistochemistry. Genome-wide expression microarray studies were performed, and vascular density was quantified after CD34 immunohistochemistry. RESULTS: A first germline variant was identified in the SDHB gene (c.158G>A; p.Gly53Glu). However, a positive SDHB immunostaining in the tumor indicated that this SDHB variant was a non-functional polymorphism. A novel TMEM127 germline mutation (c.140C>A, p.Ala47Asp) associated with a 2q11 LOH was found. Transcriptome and immunohistochemical analyses showed that TMEM127-related pheochromocytoma clusterized with NF1-related and RET-related tumors in a large series of pheochromocytomas and paragangliomas, exhibited a reduced TMEM127 mRNA expression and displayed a low vascularization. The phosphorylation of S6K observed in this tumor was suggestive of an activation of the MTOR pathway. CONCLUSIONS: Pathological and genomic data demonstrated that a TMEM127 gene mutation not previously described was causative of a new case of familial bilateral pheochromocytoma. This report highlights the importance of supplementary analyses on tumor tissue to provide an accurate pheochromocytoma/paraganglioma genetic testing result to affected patients.

[Adrenal hypertension]. / Hypertensions artérielles d'origine surrénale.

Hypertension is surgically curable in a small number of patients with adrenal hypertension, mostly in patients with Conn's adenomas or pheochromocytomas. Patients with resistant hypertension and/or hypokalemia should be screened for primary aldosteronism. The aldosterone to renin ratio is a logical initial screening test. CT-scan and adrenal vein sampling help to distinguish between idiopathic hyperplasia and Conn's adenoma. Laparoscopic surgery is indicated when there is a history of severe or recent hypertension in patients with a typical Conn's adenoma or with a lateralizing adrenal vein sampling. The diagnostic test for pheochromocytoma is the determination of plasma or urinary metanephrines. Tumours can be located by CT-scan, magnetic resonance imaging and specific scintigraphies. One pheochromocytoma in 3 or 4 results from hereditary disease.